Changes since v2 [1]: - Rebase on next/master to resolve conflicts with pending mem-hotplug and memremap_pages() changes in -mm
- Drop attempt at a generic phys_to_target_node() implementation and just follow the default fallback approach taken with memory_add_physaddr_to_nid() (Mike)
- Fix test_hmm and other compilation fixups (Ralph)
- Integrate Joao's extensions to the device-dax sub-division interface (per-device align, user-directed extent allocation). (Joao)
[1]: http://lore.kernel.org/r/159457116473.754248.7879464730875147365.stgit@dwill...
--- Merge notes:
Andrew, this series is rebased on today's next/master to resolve conflicts with some pending patches in -mm. I'd like to take it through your tree given the intersections with memremap_pages() and memory hotplug. If at all possible I'd like to see it in v5.10, but I realize time is short. Outside of the Intel identified use cases for this Joao has identified a use case for Oracle as well.
I would have sent this earlier save for the fact I am mostly offline tending to a newborn these days. Vishal has stepped up to take on care and feeding of this patchset if additional review / integration fixups are needed.
The one test feedback this wants is from Justin (justin.he@arm.com), and whether this lights up dax_kmem and now dax_hmem for him on arm64. Otherwise, Joao has written unit tests for this in his enabling of the daxctl userspace utility [2].
--- Cover:
The device-dax facility allows an address range to be directly mapped through a chardev, or optionally hotplugged to the core kernel page allocator as System-RAM. It is the mechanism for converting persistent memory (pmem) to be used as another volatile memory pool i.e. the current Memory Tiering hot topic on linux-mm.
In the case of pmem the nvdimm-namespace-label mechanism can sub-divide it, but that labeling mechanism is not available / applicable to soft-reserved ("EFI specific purpose") memory [3]. This series provides a sysfs-mechanism for the daxctl utility to enable provisioning of volatile-soft-reserved memory ranges.
The motivations for this facility are:
1/ Allow performance differentiated memory ranges to be split between kernel-managed and directly-accessed use cases.
2/ Allow physical memory to be provisioned along performance relevant address boundaries. For example, divide a memory-side cache [4] along cache-color boundaries.
3/ Parcel out soft-reserved memory to VMs using device-dax as a security / permissions boundary [5]. Specifically I have seen people (ab)using memmap=nn!ss (mark System-RAM as Persistent Memory) just to get the device-dax interface on custom address ranges. A follow-on for the VM use case is to teach device-dax to dynamically allocate 'struct page' at runtime to reduce the duplication of 'struct page' space in both the guest and the host kernel for the same physical pages.
[2]: http://lore.kernel.org/r/20200713160837.13774-11-joao.m.martins@oracle.com [3]: http://lore.kernel.org/r/157309097008.1579826.12818463304589384434.stgit@dwi... [4]: http://lore.kernel.org/r/154899811738.3165233.12325692939590944259.stgit@dwi... [5]: http://lore.kernel.org/r/20200110190313.17144-1-joao.m.martins@oracle.com
---
Dan Williams (19): x86/numa: Cleanup configuration dependent command-line options x86/numa: Add 'nohmat' option efi/fake_mem: Arrange for a resource entry per efi_fake_mem instance ACPI: HMAT: Refactor hmat_register_target_device to hmem_register_device resource: Report parent to walk_iomem_res_desc() callback mm/memory_hotplug: Introduce default phys_to_target_node() implementation ACPI: HMAT: Attach a device for each soft-reserved range device-dax: Drop the dax_region.pfn_flags attribute device-dax: Move instance creation parameters to 'struct dev_dax_data' device-dax: Make pgmap optional for instance creation device-dax: Kill dax_kmem_res device-dax: Add an allocation interface for device-dax instances device-dax: Introduce 'seed' devices drivers/base: Make device_find_child_by_name() compatible with sysfs inputs device-dax: Add resize support mm/memremap_pages: Convert to 'struct range' mm/memremap_pages: Support multiple ranges per invocation device-dax: Add dis-contiguous resource support device-dax: Introduce 'mapping' devices
Joao Martins (4): device-dax: Make align a per-device property device-dax: Add an 'align' attribute dax/hmem: Introduce dax_hmem.region_idle parameter device-dax: Add a range mapping allocation attribute
arch/powerpc/kvm/book3s_hv_uvmem.c | 14 arch/x86/include/asm/numa.h | 8 arch/x86/kernel/e820.c | 16 arch/x86/mm/numa.c | 11 arch/x86/mm/numa_emulation.c | 3 arch/x86/xen/enlighten_pv.c | 2 drivers/acpi/numa/hmat.c | 76 -- drivers/acpi/numa/srat.c | 9 drivers/base/core.c | 2 drivers/dax/Kconfig | 4 drivers/dax/Makefile | 3 drivers/dax/bus.c | 1055 ++++++++++++++++++++++++++++++-- drivers/dax/bus.h | 28 + drivers/dax/dax-private.h | 40 + drivers/dax/device.c | 132 ++-- drivers/dax/hmem.c | 56 -- drivers/dax/hmem/Makefile | 6 drivers/dax/hmem/device.c | 100 +++ drivers/dax/hmem/hmem.c | 65 ++ drivers/dax/kmem.c | 199 +++--- drivers/dax/pmem/compat.c | 2 drivers/dax/pmem/core.c | 22 - drivers/firmware/efi/x86_fake_mem.c | 12 drivers/gpu/drm/nouveau/nouveau_dmem.c | 15 drivers/nvdimm/badrange.c | 26 - drivers/nvdimm/claim.c | 13 drivers/nvdimm/nd.h | 3 drivers/nvdimm/pfn_devs.c | 13 drivers/nvdimm/pmem.c | 27 - drivers/nvdimm/region.c | 21 - drivers/pci/p2pdma.c | 12 include/acpi/acpi_numa.h | 14 include/linux/dax.h | 8 include/linux/memory_hotplug.h | 5 include/linux/memremap.h | 11 include/linux/range.h | 6 kernel/resource.c | 11 lib/test_hmm.c | 15 mm/memory_hotplug.c | 10 mm/memremap.c | 299 +++++---- tools/testing/nvdimm/dax-dev.c | 22 - tools/testing/nvdimm/test/iomap.c | 2 42 files changed, 1810 insertions(+), 588 deletions(-) delete mode 100644 drivers/dax/hmem.c create mode 100644 drivers/dax/hmem/Makefile create mode 100644 drivers/dax/hmem/device.c create mode 100644 drivers/dax/hmem/hmem.c
base-commit: 01830e6c042e8eb6eb202e05d7df8057135b4c26
In preparation for adding a new numa= option clean up the existing ones to avoid ifdefs in numa_setup(), and provide feedback when the option is numa=fake= option is invalid due to kernel config. The same does not need to be done for numa=noacpi, since the capability is already hard disabled at compile-time.
Suggested-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- arch/x86/include/asm/numa.h | 8 +++++++- arch/x86/mm/numa.c | 8 ++------ arch/x86/mm/numa_emulation.c | 3 ++- arch/x86/xen/enlighten_pv.c | 2 +- drivers/acpi/numa/srat.c | 9 +++++++-- include/acpi/acpi_numa.h | 6 +++++- 6 files changed, 24 insertions(+), 12 deletions(-)
diff --git a/arch/x86/include/asm/numa.h b/arch/x86/include/asm/numa.h index bbfde3d2662f..0aecc0b629e0 100644 --- a/arch/x86/include/asm/numa.h +++ b/arch/x86/include/asm/numa.h @@ -3,6 +3,7 @@ #define _ASM_X86_NUMA_H
#include <linux/nodemask.h> +#include <linux/errno.h>
#include <asm/topology.h> #include <asm/apicdef.h> @@ -77,7 +78,12 @@ void debug_cpumask_set_cpu(int cpu, int node, bool enable); #ifdef CONFIG_NUMA_EMU #define FAKE_NODE_MIN_SIZE ((u64)32 << 20) #define FAKE_NODE_MIN_HASH_MASK (~(FAKE_NODE_MIN_SIZE - 1UL)) -void numa_emu_cmdline(char *); +int numa_emu_cmdline(char *str); +#else /* CONFIG_NUMA_EMU */ +static inline int numa_emu_cmdline(char *str) +{ + return -EINVAL; +} #endif /* CONFIG_NUMA_EMU */
#endif /* _ASM_X86_NUMA_H */ diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c index aa76ec2d359b..87c52822cc44 100644 --- a/arch/x86/mm/numa.c +++ b/arch/x86/mm/numa.c @@ -37,14 +37,10 @@ static __init int numa_setup(char *opt) return -EINVAL; if (!strncmp(opt, "off", 3)) numa_off = 1; -#ifdef CONFIG_NUMA_EMU if (!strncmp(opt, "fake=", 5)) - numa_emu_cmdline(opt + 5); -#endif -#ifdef CONFIG_ACPI_NUMA + return numa_emu_cmdline(opt + 5); if (!strncmp(opt, "noacpi", 6)) - acpi_numa = -1; -#endif + disable_srat(); return 0; } early_param("numa", numa_setup); diff --git a/arch/x86/mm/numa_emulation.c b/arch/x86/mm/numa_emulation.c index c5174b4e318b..847c23196e57 100644 --- a/arch/x86/mm/numa_emulation.c +++ b/arch/x86/mm/numa_emulation.c @@ -13,9 +13,10 @@ static int emu_nid_to_phys[MAX_NUMNODES]; static char *emu_cmdline __initdata;
-void __init numa_emu_cmdline(char *str) +int __init numa_emu_cmdline(char *str) { emu_cmdline = str; + return 0; }
static int __init emu_find_memblk_by_nid(int nid, const struct numa_meminfo *mi) diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c index 2aab43a13a8c..64b81ba5a4d6 100644 --- a/arch/x86/xen/enlighten_pv.c +++ b/arch/x86/xen/enlighten_pv.c @@ -1350,7 +1350,7 @@ asmlinkage __visible void __init xen_start_kernel(void) * any NUMA information the kernel tries to get from ACPI will * be meaningless. Prevent it from trying. */ - acpi_numa = -1; + disable_srat(); #endif WARN_ON(xen_cpuhp_setup(xen_cpu_up_prepare_pv, xen_cpu_dead_pv));
diff --git a/drivers/acpi/numa/srat.c b/drivers/acpi/numa/srat.c index 15bbaab8500b..1b0ae0a1959b 100644 --- a/drivers/acpi/numa/srat.c +++ b/drivers/acpi/numa/srat.c @@ -27,7 +27,12 @@ static int node_to_pxm_map[MAX_NUMNODES] = { [0 ... MAX_NUMNODES - 1] = PXM_INVAL };
unsigned char acpi_srat_revision __initdata; -int acpi_numa __initdata; +static int acpi_numa __initdata; + +void __init disable_srat(void) +{ + acpi_numa = -1; +}
int pxm_to_node(int pxm) { @@ -163,7 +168,7 @@ static int __init slit_valid(struct acpi_table_slit *slit) void __init bad_srat(void) { pr_err("SRAT: SRAT not used.\n"); - acpi_numa = -1; + disable_srat(); }
int __init srat_disabled(void) diff --git a/include/acpi/acpi_numa.h b/include/acpi/acpi_numa.h index fdebcfc6c8df..8784183b2204 100644 --- a/include/acpi/acpi_numa.h +++ b/include/acpi/acpi_numa.h @@ -17,10 +17,14 @@ extern int pxm_to_node(int); extern int node_to_pxm(int); extern int acpi_map_pxm_to_node(int); extern unsigned char acpi_srat_revision; -extern int acpi_numa __initdata; +extern void disable_srat(void);
extern void bad_srat(void); extern int srat_disabled(void);
+#else /* CONFIG_ACPI_NUMA */ +static inline void disable_srat(void) +{ +} #endif /* CONFIG_ACPI_NUMA */ #endif /* __ACP_NUMA_H */
Disable parsing of the HMAT for debug, to workaround broken platform instances, or cases where it is otherwise not wanted.
Cc: x86@kernel.org Cc: "Rafael J. Wysocki" rjw@rjwysocki.net Cc: Dave Hansen dave.hansen@linux.intel.com Cc: Andy Lutomirski luto@kernel.org Cc: Peter Zijlstra peterz@infradead.org Cc: Thomas Gleixner tglx@linutronix.de Cc: Ingo Molnar mingo@redhat.com Cc: Borislav Petkov bp@alien8.de Cc: "H. Peter Anvin" hpa@zytor.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- arch/x86/mm/numa.c | 2 ++ drivers/acpi/numa/hmat.c | 8 +++++++- include/acpi/acpi_numa.h | 8 ++++++++ 3 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c index 87c52822cc44..f3805bbaa784 100644 --- a/arch/x86/mm/numa.c +++ b/arch/x86/mm/numa.c @@ -41,6 +41,8 @@ static __init int numa_setup(char *opt) return numa_emu_cmdline(opt + 5); if (!strncmp(opt, "noacpi", 6)) disable_srat(); + if (!strncmp(opt, "nohmat", 6)) + disable_hmat(); return 0; } early_param("numa", numa_setup); diff --git a/drivers/acpi/numa/hmat.c b/drivers/acpi/numa/hmat.c index 2c32cfb72370..a12e36a12618 100644 --- a/drivers/acpi/numa/hmat.c +++ b/drivers/acpi/numa/hmat.c @@ -26,6 +26,12 @@ #include <linux/sysfs.h>
static u8 hmat_revision; +static int hmat_disable __initdata; + +void __init disable_hmat(void) +{ + hmat_disable = 1; +}
static LIST_HEAD(targets); static LIST_HEAD(initiators); @@ -814,7 +820,7 @@ static __init int hmat_init(void) enum acpi_hmat_type i; acpi_status status;
- if (srat_disabled()) + if (srat_disabled() || hmat_disable) return 0;
status = acpi_get_table(ACPI_SIG_SRAT, 0, &tbl); diff --git a/include/acpi/acpi_numa.h b/include/acpi/acpi_numa.h index 8784183b2204..0e9302285f14 100644 --- a/include/acpi/acpi_numa.h +++ b/include/acpi/acpi_numa.h @@ -27,4 +27,12 @@ static inline void disable_srat(void) { } #endif /* CONFIG_ACPI_NUMA */ + +#ifdef CONFIG_ACPI_HMAT +extern void disable_hmat(void); +#else /* CONFIG_ACPI_HMAT */ +static inline void disable_hmat(void) +{ +} +#endif /* CONFIG_ACPI_HMAT */ #endif /* __ACP_NUMA_H */
On 7/31/20 8:25 PM, Dan Williams wrote:
Disable parsing of the HMAT for debug, to workaround broken platform instances, or cases where it is otherwise not wanted.
arch/x86/mm/numa.c | 2 ++ drivers/acpi/numa/hmat.c | 8 +++++++- include/acpi/acpi_numa.h | 8 ++++++++ 3 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c index 87c52822cc44..f3805bbaa784 100644 --- a/arch/x86/mm/numa.c +++ b/arch/x86/mm/numa.c @@ -41,6 +41,8 @@ static __init int numa_setup(char *opt) return numa_emu_cmdline(opt + 5); if (!strncmp(opt, "noacpi", 6)) disable_srat();
- if (!strncmp(opt, "nohmat", 6))
disable_hmat();
Hopefully that will be documented in Documentation/x86/x86_64/boot-options.rst.
return 0; } early_param("numa", numa_setup);
thanks.
On Fri, Jul 31, 2020 at 8:51 PM Randy Dunlap rdunlap@infradead.org wrote:
On 7/31/20 8:25 PM, Dan Williams wrote:
Disable parsing of the HMAT for debug, to workaround broken platform instances, or cases where it is otherwise not wanted.
arch/x86/mm/numa.c | 2 ++ drivers/acpi/numa/hmat.c | 8 +++++++- include/acpi/acpi_numa.h | 8 ++++++++ 3 files changed, 17 insertions(+), 1 deletion(-)
diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c index 87c52822cc44..f3805bbaa784 100644 --- a/arch/x86/mm/numa.c +++ b/arch/x86/mm/numa.c @@ -41,6 +41,8 @@ static __init int numa_setup(char *opt) return numa_emu_cmdline(opt + 5); if (!strncmp(opt, "noacpi", 6)) disable_srat();
if (!strncmp(opt, "nohmat", 6))disable_hmat();Hopefully that will be documented in Documentation/x86/x86_64/boot-options.rst.
Sorry, yes, you gave that feedback before. I can do a quick respin with this and the kbuild-robot compile fixups.
In preparation for attaching a platform device per iomem resource teach the efi_fake_mem code to create an e820 entry per instance. Similar to E820_TYPE_PRAM, bypass merging resource when the e820 map is sanitized.
Cc: Thomas Gleixner tglx@linutronix.de Cc: Ingo Molnar mingo@redhat.com Cc: Borislav Petkov bp@alien8.de Cc: "H. Peter Anvin" hpa@zytor.com Cc: x86@kernel.org Acked-by: Ard Biesheuvel ardb@kernel.org Signed-off-by: Dan Williams dan.j.williams@intel.com --- arch/x86/kernel/e820.c | 16 +++++++++++++++- drivers/firmware/efi/x86_fake_mem.c | 12 +++++++++--- 2 files changed, 24 insertions(+), 4 deletions(-)
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c index 983cd53ed4c9..22aad412f965 100644 --- a/arch/x86/kernel/e820.c +++ b/arch/x86/kernel/e820.c @@ -305,6 +305,20 @@ static int __init cpcompare(const void *a, const void *b) return (ap->addr != ap->entry->addr) - (bp->addr != bp->entry->addr); }
+static bool e820_nomerge(enum e820_type type) +{ + /* + * These types may indicate distinct platform ranges aligned to + * numa node, protection domain, performance domain, or other + * boundaries. Do not merge them. + */ + if (type == E820_TYPE_PRAM) + return true; + if (type == E820_TYPE_SOFT_RESERVED) + return true; + return false; +} + int __init e820__update_table(struct e820_table *table) { struct e820_entry *entries = table->entries; @@ -380,7 +394,7 @@ int __init e820__update_table(struct e820_table *table) }
/* Continue building up new map based on this information: */ - if (current_type != last_type || current_type == E820_TYPE_PRAM) { + if (current_type != last_type || e820_nomerge(current_type)) { if (last_type != 0) { new_entries[new_nr_entries].size = change_point[chg_idx]->addr - last_addr; /* Move forward only if the new size was non-zero: */ diff --git a/drivers/firmware/efi/x86_fake_mem.c b/drivers/firmware/efi/x86_fake_mem.c index e5d6d5a1b240..0bafcc1bb0f6 100644 --- a/drivers/firmware/efi/x86_fake_mem.c +++ b/drivers/firmware/efi/x86_fake_mem.c @@ -38,7 +38,7 @@ void __init efi_fake_memmap_early(void) m_start = mem->range.start; m_end = mem->range.end; for_each_efi_memory_desc(md) { - u64 start, end; + u64 start, end, size;
if (md->type != EFI_CONVENTIONAL_MEMORY) continue; @@ -58,11 +58,17 @@ void __init efi_fake_memmap_early(void) */ start = max(start, m_start); end = min(end, m_end); + size = end - start + 1;
if (end <= start) continue; - e820__range_update(start, end - start + 1, E820_TYPE_RAM, - E820_TYPE_SOFT_RESERVED); + + /* + * Ensure each efi_fake_mem instance results in + * a unique e820 resource + */ + e820__range_remove(start, size, E820_TYPE_RAM, 1); + e820__range_add(start, size, E820_TYPE_SOFT_RESERVED); e820__update_table(e820_table); } }
In preparation for exposing "Soft Reserved" memory ranges without an HMAT, move the hmem device registration to its own compilation unit and make the implementation generic.
The generic implementation drops usage acpi_map_pxm_to_online_node() that was translating ACPI proximity domain values and instead relies on numa_map_to_online_node() to determine the numa node for the device.
Cc: "Rafael J. Wysocki" rjw@rjwysocki.net Link: https://lore.kernel.org/r/158318761484.2216124.2049322072599482736.stgit@dwi... Signed-off-by: Dan Williams dan.j.williams@intel.com --- drivers/acpi/numa/hmat.c | 68 ++++----------------------------------------- drivers/dax/Kconfig | 4 +++ drivers/dax/Makefile | 3 +- drivers/dax/hmem.c | 56 ------------------------------------- drivers/dax/hmem/Makefile | 5 +++ drivers/dax/hmem/device.c | 65 +++++++++++++++++++++++++++++++++++++++++++ drivers/dax/hmem/hmem.c | 56 +++++++++++++++++++++++++++++++++++++ include/linux/dax.h | 8 +++++ 8 files changed, 145 insertions(+), 120 deletions(-) delete mode 100644 drivers/dax/hmem.c create mode 100644 drivers/dax/hmem/Makefile create mode 100644 drivers/dax/hmem/device.c create mode 100644 drivers/dax/hmem/hmem.c
diff --git a/drivers/acpi/numa/hmat.c b/drivers/acpi/numa/hmat.c index a12e36a12618..134bcb40b2af 100644 --- a/drivers/acpi/numa/hmat.c +++ b/drivers/acpi/numa/hmat.c @@ -24,6 +24,7 @@ #include <linux/mutex.h> #include <linux/node.h> #include <linux/sysfs.h> +#include <linux/dax.h>
static u8 hmat_revision; static int hmat_disable __initdata; @@ -640,66 +641,6 @@ static void hmat_register_target_perf(struct memory_target *target) node_set_perf_attrs(mem_nid, &target->hmem_attrs, 0); }
-static void hmat_register_target_device(struct memory_target *target, - struct resource *r) -{ - /* define a clean / non-busy resource for the platform device */ - struct resource res = { - .start = r->start, - .end = r->end, - .flags = IORESOURCE_MEM, - }; - struct platform_device *pdev; - struct memregion_info info; - int rc, id; - - rc = region_intersects(res.start, resource_size(&res), IORESOURCE_MEM, - IORES_DESC_SOFT_RESERVED); - if (rc != REGION_INTERSECTS) - return; - - id = memregion_alloc(GFP_KERNEL); - if (id < 0) { - pr_err("memregion allocation failure for %pr\n", &res); - return; - } - - pdev = platform_device_alloc("hmem", id); - if (!pdev) { - pr_err("hmem device allocation failure for %pr\n", &res); - goto out_pdev; - } - - pdev->dev.numa_node = acpi_map_pxm_to_online_node(target->memory_pxm); - info = (struct memregion_info) { - .target_node = acpi_map_pxm_to_node(target->memory_pxm), - }; - rc = platform_device_add_data(pdev, &info, sizeof(info)); - if (rc < 0) { - pr_err("hmem memregion_info allocation failure for %pr\n", &res); - goto out_pdev; - } - - rc = platform_device_add_resources(pdev, &res, 1); - if (rc < 0) { - pr_err("hmem resource allocation failure for %pr\n", &res); - goto out_resource; - } - - rc = platform_device_add(pdev); - if (rc < 0) { - dev_err(&pdev->dev, "device add failed for %pr\n", &res); - goto out_resource; - } - - return; - -out_resource: - put_device(&pdev->dev); -out_pdev: - memregion_free(id); -} - static void hmat_register_target_devices(struct memory_target *target) { struct resource *res; @@ -711,8 +652,11 @@ static void hmat_register_target_devices(struct memory_target *target) if (!IS_ENABLED(CONFIG_DEV_DAX_HMEM)) return;
- for (res = target->memregions.child; res; res = res->sibling) - hmat_register_target_device(target, res); + for (res = target->memregions.child; res; res = res->sibling) { + int target_nid = acpi_map_pxm_to_node(target->memory_pxm); + + hmem_register_device(target_nid, res); + } }
static void hmat_register_target(struct memory_target *target) diff --git a/drivers/dax/Kconfig b/drivers/dax/Kconfig index 3b6c06f07326..a229f45d34aa 100644 --- a/drivers/dax/Kconfig +++ b/drivers/dax/Kconfig @@ -48,6 +48,10 @@ config DEV_DAX_HMEM
Say M if unsure.
+config DEV_DAX_HMEM_DEVICES + depends on DEV_DAX_HMEM + def_bool y + config DEV_DAX_KMEM tristate "KMEM DAX: volatile-use of persistent memory" default DEV_DAX diff --git a/drivers/dax/Makefile b/drivers/dax/Makefile index 80065b38b3c4..9d4ba672d305 100644 --- a/drivers/dax/Makefile +++ b/drivers/dax/Makefile @@ -2,11 +2,10 @@ obj-$(CONFIG_DAX) += dax.o obj-$(CONFIG_DEV_DAX) += device_dax.o obj-$(CONFIG_DEV_DAX_KMEM) += kmem.o -obj-$(CONFIG_DEV_DAX_HMEM) += dax_hmem.o
dax-y := super.o dax-y += bus.o device_dax-y := device.o -dax_hmem-y := hmem.o
obj-y += pmem/ +obj-y += hmem/ diff --git a/drivers/dax/hmem.c b/drivers/dax/hmem.c deleted file mode 100644 index fe7214daf62e..000000000000 --- a/drivers/dax/hmem.c +++ /dev/null @@ -1,56 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -#include <linux/platform_device.h> -#include <linux/memregion.h> -#include <linux/module.h> -#include <linux/pfn_t.h> -#include "bus.h" - -static int dax_hmem_probe(struct platform_device *pdev) -{ - struct device *dev = &pdev->dev; - struct dev_pagemap pgmap = { }; - struct dax_region *dax_region; - struct memregion_info *mri; - struct dev_dax *dev_dax; - struct resource *res; - - res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (!res) - return -ENOMEM; - - mri = dev->platform_data; - memcpy(&pgmap.res, res, sizeof(*res)); - - dax_region = alloc_dax_region(dev, pdev->id, res, mri->target_node, - PMD_SIZE, PFN_DEV|PFN_MAP); - if (!dax_region) - return -ENOMEM; - - dev_dax = devm_create_dev_dax(dax_region, 0, &pgmap); - if (IS_ERR(dev_dax)) - return PTR_ERR(dev_dax); - - /* child dev_dax instances now own the lifetime of the dax_region */ - dax_region_put(dax_region); - return 0; -} - -static int dax_hmem_remove(struct platform_device *pdev) -{ - /* devm handles teardown */ - return 0; -} - -static struct platform_driver dax_hmem_driver = { - .probe = dax_hmem_probe, - .remove = dax_hmem_remove, - .driver = { - .name = "hmem", - }, -}; - -module_platform_driver(dax_hmem_driver); - -MODULE_ALIAS("platform:hmem*"); -MODULE_LICENSE("GPL v2"); -MODULE_AUTHOR("Intel Corporation"); diff --git a/drivers/dax/hmem/Makefile b/drivers/dax/hmem/Makefile new file mode 100644 index 000000000000..a9d353d0c9ed --- /dev/null +++ b/drivers/dax/hmem/Makefile @@ -0,0 +1,5 @@ +# SPDX-License-Identifier: GPL-2.0 +obj-$(CONFIG_DEV_DAX_HMEM) += dax_hmem.o +obj-$(CONFIG_DEV_DAX_HMEM_DEVICES) += device.o + +dax_hmem-y := hmem.o diff --git a/drivers/dax/hmem/device.c b/drivers/dax/hmem/device.c new file mode 100644 index 000000000000..b9dd6b27745c --- /dev/null +++ b/drivers/dax/hmem/device.c @@ -0,0 +1,65 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/platform_device.h> +#include <linux/memregion.h> +#include <linux/module.h> +#include <linux/dax.h> +#include <linux/mm.h> + +void hmem_register_device(int target_nid, struct resource *r) +{ + /* define a clean / non-busy resource for the platform device */ + struct resource res = { + .start = r->start, + .end = r->end, + .flags = IORESOURCE_MEM, + }; + struct platform_device *pdev; + struct memregion_info info; + int rc, id; + + rc = region_intersects(res.start, resource_size(&res), IORESOURCE_MEM, + IORES_DESC_SOFT_RESERVED); + if (rc != REGION_INTERSECTS) + return; + + id = memregion_alloc(GFP_KERNEL); + if (id < 0) { + pr_err("memregion allocation failure for %pr\n", &res); + return; + } + + pdev = platform_device_alloc("hmem", id); + if (!pdev) { + pr_err("hmem device allocation failure for %pr\n", &res); + goto out_pdev; + } + + pdev->dev.numa_node = numa_map_to_online_node(target_nid); + info = (struct memregion_info) { + .target_node = target_nid, + }; + rc = platform_device_add_data(pdev, &info, sizeof(info)); + if (rc < 0) { + pr_err("hmem memregion_info allocation failure for %pr\n", &res); + goto out_pdev; + } + + rc = platform_device_add_resources(pdev, &res, 1); + if (rc < 0) { + pr_err("hmem resource allocation failure for %pr\n", &res); + goto out_resource; + } + + rc = platform_device_add(pdev); + if (rc < 0) { + dev_err(&pdev->dev, "device add failed for %pr\n", &res); + goto out_resource; + } + + return; + +out_resource: + put_device(&pdev->dev); +out_pdev: + memregion_free(id); +} diff --git a/drivers/dax/hmem/hmem.c b/drivers/dax/hmem/hmem.c new file mode 100644 index 000000000000..29ceb5795297 --- /dev/null +++ b/drivers/dax/hmem/hmem.c @@ -0,0 +1,56 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/platform_device.h> +#include <linux/memregion.h> +#include <linux/module.h> +#include <linux/pfn_t.h> +#include "../bus.h" + +static int dax_hmem_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct dev_pagemap pgmap = { }; + struct dax_region *dax_region; + struct memregion_info *mri; + struct dev_dax *dev_dax; + struct resource *res; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENOMEM; + + mri = dev->platform_data; + memcpy(&pgmap.res, res, sizeof(*res)); + + dax_region = alloc_dax_region(dev, pdev->id, res, mri->target_node, + PMD_SIZE, PFN_DEV|PFN_MAP); + if (!dax_region) + return -ENOMEM; + + dev_dax = devm_create_dev_dax(dax_region, 0, &pgmap); + if (IS_ERR(dev_dax)) + return PTR_ERR(dev_dax); + + /* child dev_dax instances now own the lifetime of the dax_region */ + dax_region_put(dax_region); + return 0; +} + +static int dax_hmem_remove(struct platform_device *pdev) +{ + /* devm handles teardown */ + return 0; +} + +static struct platform_driver dax_hmem_driver = { + .probe = dax_hmem_probe, + .remove = dax_hmem_remove, + .driver = { + .name = "hmem", + }, +}; + +module_platform_driver(dax_hmem_driver); + +MODULE_ALIAS("platform:hmem*"); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Intel Corporation"); diff --git a/include/linux/dax.h b/include/linux/dax.h index 6904d4e0b2e0..5d2c3d9aeb5e 100644 --- a/include/linux/dax.h +++ b/include/linux/dax.h @@ -221,4 +221,12 @@ static inline bool dax_mapping(struct address_space *mapping) return mapping->host && IS_DAX(mapping->host); }
+#ifdef CONFIG_DEV_DAX_HMEM_DEVICES +void hmem_register_device(int target_nid, struct resource *r); +#else +static inline void hmem_register_device(int target_nid, struct resource *r) +{ +} +#endif + #endif
In support of detecting whether a resource might have been been claimed, report the parent to the walk_iomem_res_desc() callback. For example, the ACPI HMAT parser publishes "hmem" platform devices per target range. However, if the HMAT is disabled / missing a fallback driver can attach devices to the raw memory ranges as a fallback if it sees unclaimed / orphan "Soft Reserved" resources in the resource tree.
Otherwise, find_next_iomem_res() returns a resource with garbage data from the stack allocation in __walk_iomem_res_desc() for the res->parent field.
There are currently no users that expect ->child and ->sibling to be valid, and the resource_lock would be needed to traverse them. Use a compound literal to implicitly zero initialize the fields that are not being returned in addition to setting ->parent.
Cc: Jason Gunthorpe jgg@mellanox.com Cc: Dave Hansen dave.hansen@linux.intel.com Cc: Wei Yang richardw.yang@linux.intel.com Cc: Tom Lendacky thomas.lendacky@amd.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- kernel/resource.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/kernel/resource.c b/kernel/resource.c index 841737bbda9e..f1175ce93a1d 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -382,10 +382,13 @@ static int find_next_iomem_res(resource_size_t start, resource_size_t end,
if (p) { /* copy data */ - res->start = max(start, p->start); - res->end = min(end, p->end); - res->flags = p->flags; - res->desc = p->desc; + *res = (struct resource) { + .start = max(start, p->start), + .end = min(end, p->end), + .flags = p->flags, + .desc = p->desc, + .parent = p->parent, + }; }
read_unlock(&resource_lock);
In preparation to set a fallback value for dev_dax->target_node, introduce generic fallback helpers for phys_to_target_node()
A generic implementation based on node-data or memblock was proposed, but as noted by Mike:
"Here again, I would prefer to add a weak default for phys_to_target_node() because the "generic" implementation is not really generic.
The fallback to reserved ranges is x86 specfic because on x86 most of the reserved areas is not in memblock.memory. AFAIK, no other architecture does this."
The info message in the generic memory_add_physaddr_to_nid() implementation is fixed up to properly reflect that memory_add_physaddr_to_nid() communicates "online" node info and phys_to_target_node() indicates "target / to-be-onlined" node info.
Cc: David Hildenbrand david@redhat.com Cc: Mike Rapoport rppt@linux.ibm.com Cc: Jia He justin.he@arm.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- arch/x86/mm/numa.c | 1 - include/linux/memory_hotplug.h | 5 +++++ mm/memory_hotplug.c | 10 +++++++++- 3 files changed, 14 insertions(+), 2 deletions(-)
diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c index f3805bbaa784..c62e274d52d0 100644 --- a/arch/x86/mm/numa.c +++ b/arch/x86/mm/numa.c @@ -917,7 +917,6 @@ int phys_to_target_node(phys_addr_t start)
return meminfo_to_nid(&numa_reserved_meminfo, start); } -EXPORT_SYMBOL_GPL(phys_to_target_node);
int memory_add_physaddr_to_nid(u64 start) { diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h index 375515803cd8..dcdc7d6206d5 100644 --- a/include/linux/memory_hotplug.h +++ b/include/linux/memory_hotplug.h @@ -151,11 +151,16 @@ int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
#ifdef CONFIG_NUMA extern int memory_add_physaddr_to_nid(u64 start); +extern int phys_to_target_node(u64 start); #else static inline int memory_add_physaddr_to_nid(u64 start) { return 0; } +static inline int phys_to_target_node(u64 start) +{ + return 0; +} #endif
#ifdef CONFIG_HAVE_ARCH_NODEDATA_EXTENSION diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index dcdf3271f87e..426b79adf529 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -353,11 +353,19 @@ int __ref __add_pages(int nid, unsigned long pfn, unsigned long nr_pages, #ifdef CONFIG_NUMA int __weak memory_add_physaddr_to_nid(u64 start) { - pr_info_once("Unknown target node for memory at 0x%llx, assuming node 0\n", + pr_info_once("Unknown online node for memory at 0x%llx, assuming node 0\n", start); return 0; } EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid); + +int __weak phys_to_target_node(u64 start) +{ + pr_info_once("Unknown target node for memory at 0x%llx, assuming node 0\n", + start); + return 0; +} +EXPORT_SYMBOL_GPL(phys_to_target_node); #endif
/* find the smallest valid pfn in the range [start_pfn, end_pfn) */
The hmem enabling in commit 'cf8741ac57ed ("ACPI: NUMA: HMAT: Register "soft reserved" memory as an "hmem" device")' only registered ranges to the hmem driver for each soft-reservation that also appeared in the HMAT. While this is meant to encourage platform firmware to "do the right thing" and publish an HMAT, the corollary is that platforms that fail to publish an accurate HMAT will strand memory from Linux usage. Additionally, the "efi_fake_mem" kernel command line option enabling will strand memory by default without an HMAT.
Arrange for "soft reserved" memory that goes unclaimed by HMAT entries to be published as raw resource ranges for the hmem driver to consume.
Include a module parameter to disable either this fallback behavior, or the hmat enabling from creating hmem devices. The module parameter requires the hmem device enabling to have unique name in the module namespace: "device_hmem".
The driver depends on the architecture providing phys_to_target_node() which is only x86 via numa_meminfo() and arm64 via a generic memblock implementation.
Cc: Jonathan Cameron Jonathan.Cameron@huawei.com Cc: Brice Goglin Brice.Goglin@inria.fr Cc: Ard Biesheuvel ard.biesheuvel@linaro.org Cc: "Rafael J. Wysocki" rjw@rjwysocki.net Cc: Jeff Moyer jmoyer@redhat.com Cc: Catalin Marinas catalin.marinas@arm.com Cc: Will Deacon will@kernel.org Reviewed-by: Joao Martins joao.m.martins@oracle.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- drivers/dax/hmem/Makefile | 3 ++- drivers/dax/hmem/device.c | 35 +++++++++++++++++++++++++++++++++++ 2 files changed, 37 insertions(+), 1 deletion(-)
diff --git a/drivers/dax/hmem/Makefile b/drivers/dax/hmem/Makefile index a9d353d0c9ed..57377b4c3d47 100644 --- a/drivers/dax/hmem/Makefile +++ b/drivers/dax/hmem/Makefile @@ -1,5 +1,6 @@ # SPDX-License-Identifier: GPL-2.0 obj-$(CONFIG_DEV_DAX_HMEM) += dax_hmem.o -obj-$(CONFIG_DEV_DAX_HMEM_DEVICES) += device.o +obj-$(CONFIG_DEV_DAX_HMEM_DEVICES) += device_hmem.o
+device_hmem-y := device.o dax_hmem-y := hmem.o diff --git a/drivers/dax/hmem/device.c b/drivers/dax/hmem/device.c index b9dd6b27745c..cb6401c9e9a4 100644 --- a/drivers/dax/hmem/device.c +++ b/drivers/dax/hmem/device.c @@ -5,6 +5,9 @@ #include <linux/dax.h> #include <linux/mm.h>
+static bool nohmem; +module_param_named(disable, nohmem, bool, 0444); + void hmem_register_device(int target_nid, struct resource *r) { /* define a clean / non-busy resource for the platform device */ @@ -17,6 +20,9 @@ void hmem_register_device(int target_nid, struct resource *r) struct memregion_info info; int rc, id;
+ if (nohmem) + return; + rc = region_intersects(res.start, resource_size(&res), IORESOURCE_MEM, IORES_DESC_SOFT_RESERVED); if (rc != REGION_INTERSECTS) @@ -63,3 +69,32 @@ void hmem_register_device(int target_nid, struct resource *r) out_pdev: memregion_free(id); } + +static __init int hmem_register_one(struct resource *res, void *data) +{ + /* + * If the resource is not a top-level resource it was already + * assigned to a device by the HMAT parsing. + */ + if (res->parent != &iomem_resource) { + pr_info("HMEM: skip %pr, already claimed\n", res); + return 0; + } + + hmem_register_device(phys_to_target_node(res->start), res); + + return 0; +} + +static __init int hmem_init(void) +{ + walk_iomem_res_desc(IORES_DESC_SOFT_RESERVED, + IORESOURCE_MEM, 0, -1, NULL, hmem_register_one); + return 0; +} + +/* + * As this is a fallback for address ranges unclaimed by the ACPI HMAT + * parsing it must be at an initcall level greater than hmat_init(). + */ +late_initcall(hmem_init);
All callers specify the same flags to alloc_dax_region(), so there is no need to allow for anything other than PFN_DEV|PFN_MAP, or carry a ->pfn_flags around on the region. Device-dax instances are always page backed.
Cc: Vishal Verma vishal.l.verma@intel.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- drivers/dax/bus.c | 4 +--- drivers/dax/bus.h | 3 +-- drivers/dax/dax-private.h | 2 -- drivers/dax/device.c | 26 +++----------------------- drivers/dax/hmem/hmem.c | 2 +- drivers/dax/pmem/core.c | 3 +-- 6 files changed, 7 insertions(+), 33 deletions(-)
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index df238c8b6ef2..f06ffa66cd78 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -226,8 +226,7 @@ static void dax_region_unregister(void *region) }
struct dax_region *alloc_dax_region(struct device *parent, int region_id, - struct resource *res, int target_node, unsigned int align, - unsigned long long pfn_flags) + struct resource *res, int target_node, unsigned int align) { struct dax_region *dax_region;
@@ -251,7 +250,6 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id,
dev_set_drvdata(parent, dax_region); memcpy(&dax_region->res, res, sizeof(*res)); - dax_region->pfn_flags = pfn_flags; kref_init(&dax_region->kref); dax_region->id = region_id; dax_region->align = align; diff --git a/drivers/dax/bus.h b/drivers/dax/bus.h index 9e4eba67e8b9..55577e9791da 100644 --- a/drivers/dax/bus.h +++ b/drivers/dax/bus.h @@ -10,8 +10,7 @@ struct dax_device; struct dax_region; void dax_region_put(struct dax_region *dax_region); struct dax_region *alloc_dax_region(struct device *parent, int region_id, - struct resource *res, int target_node, unsigned int align, - unsigned long long flags); + struct resource *res, int target_node, unsigned int align);
enum dev_dax_subsys { DEV_DAX_BUS, diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h index 16850d5388ab..8a4c40ccd2ef 100644 --- a/drivers/dax/dax-private.h +++ b/drivers/dax/dax-private.h @@ -23,7 +23,6 @@ void dax_bus_exit(void); * @dev: parent device backing this region * @align: allocation and mapping alignment for child dax devices * @res: physical address range of the region - * @pfn_flags: identify whether the pfns are paged back or not */ struct dax_region { int id; @@ -32,7 +31,6 @@ struct dax_region { struct device *dev; unsigned int align; struct resource res; - unsigned long long pfn_flags; };
/** diff --git a/drivers/dax/device.c b/drivers/dax/device.c index 4c0af2eb7e19..bffef1b21144 100644 --- a/drivers/dax/device.c +++ b/drivers/dax/device.c @@ -41,14 +41,6 @@ static int check_vma(struct dev_dax *dev_dax, struct vm_area_struct *vma, return -EINVAL; }
- if ((dax_region->pfn_flags & (PFN_DEV|PFN_MAP)) == PFN_DEV - && (vma->vm_flags & VM_DONTCOPY) == 0) { - dev_info_ratelimited(dev, - "%s: %s: fail, dax range requires MADV_DONTFORK\n", - current->comm, func); - return -EINVAL; - } - if (!vma_is_dax(vma)) { dev_info_ratelimited(dev, "%s: %s: fail, vma is not DAX capable\n", @@ -102,7 +94,7 @@ static vm_fault_t __dev_dax_pte_fault(struct dev_dax *dev_dax, return VM_FAULT_SIGBUS; }
- *pfn = phys_to_pfn_t(phys, dax_region->pfn_flags); + *pfn = phys_to_pfn_t(phys, PFN_DEV|PFN_MAP);
return vmf_insert_mixed(vmf->vma, vmf->address, *pfn); } @@ -127,12 +119,6 @@ static vm_fault_t __dev_dax_pmd_fault(struct dev_dax *dev_dax, return VM_FAULT_SIGBUS; }
- /* dax pmd mappings require pfn_t_devmap() */ - if ((dax_region->pfn_flags & (PFN_DEV|PFN_MAP)) != (PFN_DEV|PFN_MAP)) { - dev_dbg(dev, "region lacks devmap flags\n"); - return VM_FAULT_SIGBUS; - } - if (fault_size < dax_region->align) return VM_FAULT_SIGBUS; else if (fault_size > dax_region->align) @@ -150,7 +136,7 @@ static vm_fault_t __dev_dax_pmd_fault(struct dev_dax *dev_dax, return VM_FAULT_SIGBUS; }
- *pfn = phys_to_pfn_t(phys, dax_region->pfn_flags); + *pfn = phys_to_pfn_t(phys, PFN_DEV|PFN_MAP);
return vmf_insert_pfn_pmd(vmf, *pfn, vmf->flags & FAULT_FLAG_WRITE); } @@ -177,12 +163,6 @@ static vm_fault_t __dev_dax_pud_fault(struct dev_dax *dev_dax, return VM_FAULT_SIGBUS; }
- /* dax pud mappings require pfn_t_devmap() */ - if ((dax_region->pfn_flags & (PFN_DEV|PFN_MAP)) != (PFN_DEV|PFN_MAP)) { - dev_dbg(dev, "region lacks devmap flags\n"); - return VM_FAULT_SIGBUS; - } - if (fault_size < dax_region->align) return VM_FAULT_SIGBUS; else if (fault_size > dax_region->align) @@ -200,7 +180,7 @@ static vm_fault_t __dev_dax_pud_fault(struct dev_dax *dev_dax, return VM_FAULT_SIGBUS; }
- *pfn = phys_to_pfn_t(phys, dax_region->pfn_flags); + *pfn = phys_to_pfn_t(phys, PFN_DEV|PFN_MAP);
return vmf_insert_pfn_pud(vmf, *pfn, vmf->flags & FAULT_FLAG_WRITE); } diff --git a/drivers/dax/hmem/hmem.c b/drivers/dax/hmem/hmem.c index 29ceb5795297..506893861253 100644 --- a/drivers/dax/hmem/hmem.c +++ b/drivers/dax/hmem/hmem.c @@ -22,7 +22,7 @@ static int dax_hmem_probe(struct platform_device *pdev) memcpy(&pgmap.res, res, sizeof(*res));
dax_region = alloc_dax_region(dev, pdev->id, res, mri->target_node, - PMD_SIZE, PFN_DEV|PFN_MAP); + PMD_SIZE); if (!dax_region) return -ENOMEM;
diff --git a/drivers/dax/pmem/core.c b/drivers/dax/pmem/core.c index 2bedf8414fff..ea52bb77a294 100644 --- a/drivers/dax/pmem/core.c +++ b/drivers/dax/pmem/core.c @@ -53,8 +53,7 @@ struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys) memcpy(&res, &pgmap.res, sizeof(res)); res.start += offset; dax_region = alloc_dax_region(dev, region_id, &res, - nd_region->target_node, le32_to_cpu(pfn_sb->align), - PFN_DEV|PFN_MAP); + nd_region->target_node, le32_to_cpu(pfn_sb->align)); if (!dax_region) return ERR_PTR(-ENOMEM);
In preparation for adding more parameters to instance creation, move existing parameters to a new struct.
Cc: Vishal Verma vishal.l.verma@intel.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- drivers/dax/bus.c | 14 +++++++------- drivers/dax/bus.h | 16 ++++++++-------- drivers/dax/hmem/hmem.c | 8 +++++++- drivers/dax/pmem/core.c | 9 ++++++++- 4 files changed, 30 insertions(+), 17 deletions(-)
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index f06ffa66cd78..dffa4655e128 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -395,9 +395,9 @@ static void unregister_dev_dax(void *dev) put_device(dev); }
-struct dev_dax *__devm_create_dev_dax(struct dax_region *dax_region, int id, - struct dev_pagemap *pgmap, enum dev_dax_subsys subsys) +struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) { + struct dax_region *dax_region = data->dax_region; struct device *parent = dax_region->dev; struct dax_device *dax_dev; struct dev_dax *dev_dax; @@ -405,14 +405,14 @@ struct dev_dax *__devm_create_dev_dax(struct dax_region *dax_region, int id, struct device *dev; int rc = -ENOMEM;
- if (id < 0) + if (data->id < 0) return ERR_PTR(-EINVAL);
dev_dax = kzalloc(sizeof(*dev_dax), GFP_KERNEL); if (!dev_dax) return ERR_PTR(-ENOMEM);
- memcpy(&dev_dax->pgmap, pgmap, sizeof(*pgmap)); + memcpy(&dev_dax->pgmap, data->pgmap, sizeof(struct dev_pagemap));
/* * No 'host' or dax_operations since there is no access to this @@ -438,13 +438,13 @@ struct dev_dax *__devm_create_dev_dax(struct dax_region *dax_region, int id,
inode = dax_inode(dax_dev); dev->devt = inode->i_rdev; - if (subsys == DEV_DAX_BUS) + if (data->subsys == DEV_DAX_BUS) dev->bus = &dax_bus_type; else dev->class = dax_class; dev->parent = parent; dev->type = &dev_dax_type; - dev_set_name(dev, "dax%d.%d", dax_region->id, id); + dev_set_name(dev, "dax%d.%d", dax_region->id, data->id);
rc = device_add(dev); if (rc) { @@ -464,7 +464,7 @@ struct dev_dax *__devm_create_dev_dax(struct dax_region *dax_region, int id,
return ERR_PTR(rc); } -EXPORT_SYMBOL_GPL(__devm_create_dev_dax); +EXPORT_SYMBOL_GPL(devm_create_dev_dax);
static int match_always_count;
diff --git a/drivers/dax/bus.h b/drivers/dax/bus.h index 55577e9791da..299c2e7fac09 100644 --- a/drivers/dax/bus.h +++ b/drivers/dax/bus.h @@ -13,18 +13,18 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id, struct resource *res, int target_node, unsigned int align);
enum dev_dax_subsys { - DEV_DAX_BUS, + DEV_DAX_BUS = 0, /* zeroed dev_dax_data picks this by default */ DEV_DAX_CLASS, };
-struct dev_dax *__devm_create_dev_dax(struct dax_region *dax_region, int id, - struct dev_pagemap *pgmap, enum dev_dax_subsys subsys); +struct dev_dax_data { + struct dax_region *dax_region; + struct dev_pagemap *pgmap; + enum dev_dax_subsys subsys; + int id; +};
-static inline struct dev_dax *devm_create_dev_dax(struct dax_region *dax_region, - int id, struct dev_pagemap *pgmap) -{ - return __devm_create_dev_dax(dax_region, id, pgmap, DEV_DAX_BUS); -} +struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data);
/* to be deleted when DEV_DAX_CLASS is removed */ struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys); diff --git a/drivers/dax/hmem/hmem.c b/drivers/dax/hmem/hmem.c index 506893861253..b84fe17178d8 100644 --- a/drivers/dax/hmem/hmem.c +++ b/drivers/dax/hmem/hmem.c @@ -11,6 +11,7 @@ static int dax_hmem_probe(struct platform_device *pdev) struct dev_pagemap pgmap = { }; struct dax_region *dax_region; struct memregion_info *mri; + struct dev_dax_data data; struct dev_dax *dev_dax; struct resource *res;
@@ -26,7 +27,12 @@ static int dax_hmem_probe(struct platform_device *pdev) if (!dax_region) return -ENOMEM;
- dev_dax = devm_create_dev_dax(dax_region, 0, &pgmap); + data = (struct dev_dax_data) { + .dax_region = dax_region, + .id = 0, + .pgmap = &pgmap, + }; + dev_dax = devm_create_dev_dax(&data); if (IS_ERR(dev_dax)) return PTR_ERR(dev_dax);
diff --git a/drivers/dax/pmem/core.c b/drivers/dax/pmem/core.c index ea52bb77a294..08ee5947a49c 100644 --- a/drivers/dax/pmem/core.c +++ b/drivers/dax/pmem/core.c @@ -14,6 +14,7 @@ struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys) resource_size_t offset; struct nd_pfn_sb *pfn_sb; struct dev_dax *dev_dax; + struct dev_dax_data data; struct nd_namespace_io *nsio; struct dax_region *dax_region; struct dev_pagemap pgmap = { }; @@ -57,7 +58,13 @@ struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys) if (!dax_region) return ERR_PTR(-ENOMEM);
- dev_dax = __devm_create_dev_dax(dax_region, id, &pgmap, subsys); + data = (struct dev_dax_data) { + .dax_region = dax_region, + .id = id, + .pgmap = &pgmap, + .subsys = subsys, + }; + dev_dax = devm_create_dev_dax(&data);
/* child dev_dax instances now own the lifetime of the dax_region */ dax_region_put(dax_region);
The passed in dev_pagemap is only required in the pmem case as the libnvdimm core may have reserved a vmem_altmap for dev_memremap_pages() to place the memmap in pmem directly. In the hmem case there is no agent reserving an altmap so it can all be handled by a core internal default.
Pass the resource range via a new @range property of 'struct dev_dax_data'.
Cc: Vishal Verma vishal.l.verma@intel.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- drivers/dax/bus.c | 29 +++++++++++++++-------------- drivers/dax/bus.h | 2 ++ drivers/dax/dax-private.h | 9 ++++++++- drivers/dax/device.c | 28 +++++++++++++++++++--------- drivers/dax/hmem/hmem.c | 8 ++++---- drivers/dax/kmem.c | 12 ++++++------ drivers/dax/pmem/core.c | 4 ++++ tools/testing/nvdimm/dax-dev.c | 8 ++++---- 8 files changed, 62 insertions(+), 38 deletions(-)
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index dffa4655e128..96bd64ba95a5 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -271,7 +271,7 @@ static ssize_t size_show(struct device *dev, struct device_attribute *attr, char *buf) { struct dev_dax *dev_dax = to_dev_dax(dev); - unsigned long long size = resource_size(&dev_dax->region->res); + unsigned long long size = range_len(&dev_dax->range);
return sprintf(buf, "%llu\n", size); } @@ -293,19 +293,12 @@ static ssize_t target_node_show(struct device *dev, } static DEVICE_ATTR_RO(target_node);
-static unsigned long long dev_dax_resource(struct dev_dax *dev_dax) -{ - struct dax_region *dax_region = dev_dax->region; - - return dax_region->res.start; -} - static ssize_t resource_show(struct device *dev, struct device_attribute *attr, char *buf) { struct dev_dax *dev_dax = to_dev_dax(dev);
- return sprintf(buf, "%#llx\n", dev_dax_resource(dev_dax)); + return sprintf(buf, "%#llx\n", dev_dax->range.start); } static DEVICE_ATTR(resource, 0400, resource_show, NULL);
@@ -376,6 +369,7 @@ static void dev_dax_release(struct device *dev)
dax_region_put(dax_region); put_dax(dax_dev); + kfree(dev_dax->pgmap); kfree(dev_dax); }
@@ -412,7 +406,12 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) if (!dev_dax) return ERR_PTR(-ENOMEM);
- memcpy(&dev_dax->pgmap, data->pgmap, sizeof(struct dev_pagemap)); + if (data->pgmap) { + dev_dax->pgmap = kmemdup(data->pgmap, + sizeof(struct dev_pagemap), GFP_KERNEL); + if (!dev_dax->pgmap) + goto err_pgmap; + }
/* * No 'host' or dax_operations since there is no access to this @@ -421,18 +420,19 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) dax_dev = alloc_dax(dev_dax, NULL, NULL, DAXDEV_F_SYNC); if (IS_ERR(dax_dev)) { rc = PTR_ERR(dax_dev); - goto err; + goto err_alloc_dax; }
/* a device_dax instance is dead while the driver is not attached */ kill_dax(dax_dev);
- /* from here on we're committed to teardown via dax_dev_release() */ + /* from here on we're committed to teardown via dev_dax_release() */ dev = &dev_dax->dev; device_initialize(dev);
dev_dax->dax_dev = dax_dev; dev_dax->region = dax_region; + dev_dax->range = data->range; dev_dax->target_node = dax_region->target_node; kref_get(&dax_region->kref);
@@ -458,8 +458,9 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) return ERR_PTR(rc);
return dev_dax; - - err: +err_alloc_dax: + kfree(dev_dax->pgmap); +err_pgmap: kfree(dev_dax);
return ERR_PTR(rc); diff --git a/drivers/dax/bus.h b/drivers/dax/bus.h index 299c2e7fac09..4aeb36da83a4 100644 --- a/drivers/dax/bus.h +++ b/drivers/dax/bus.h @@ -3,6 +3,7 @@ #ifndef __DAX_BUS_H__ #define __DAX_BUS_H__ #include <linux/device.h> +#include <linux/range.h>
struct dev_dax; struct resource; @@ -21,6 +22,7 @@ struct dev_dax_data { struct dax_region *dax_region; struct dev_pagemap *pgmap; enum dev_dax_subsys subsys; + struct range range; int id; };
diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h index 8a4c40ccd2ef..6779f683671d 100644 --- a/drivers/dax/dax-private.h +++ b/drivers/dax/dax-private.h @@ -41,6 +41,7 @@ struct dax_region { * @target_node: effective numa node if dev_dax memory range is onlined * @dev - device core * @pgmap - pgmap for memmap setup / lifetime (driver owned) + * @range: resource range for the instance * @dax_mem_res: physical address range of hotadded DAX memory * @dax_mem_name: name for hotadded DAX memory via add_memory_driver_managed() */ @@ -49,10 +50,16 @@ struct dev_dax { struct dax_device *dax_dev; int target_node; struct device dev; - struct dev_pagemap pgmap; + struct dev_pagemap *pgmap; + struct range range; struct resource *dax_kmem_res; };
+static inline u64 range_len(struct range *range) +{ + return range->end - range->start + 1; +} + static inline struct dev_dax *to_dev_dax(struct device *dev) { return container_of(dev, struct dev_dax, dev); diff --git a/drivers/dax/device.c b/drivers/dax/device.c index bffef1b21144..a86b2c9788c5 100644 --- a/drivers/dax/device.c +++ b/drivers/dax/device.c @@ -55,12 +55,12 @@ static int check_vma(struct dev_dax *dev_dax, struct vm_area_struct *vma, __weak phys_addr_t dax_pgoff_to_phys(struct dev_dax *dev_dax, pgoff_t pgoff, unsigned long size) { - struct resource *res = &dev_dax->region->res; + struct range *range = &dev_dax->range; phys_addr_t phys;
- phys = pgoff * PAGE_SIZE + res->start; - if (phys >= res->start && phys <= res->end) { - if (phys + size - 1 <= res->end) + phys = pgoff * PAGE_SIZE + range->start; + if (phys >= range->start && phys <= range->end) { + if (phys + size - 1 <= range->end) return phys; }
@@ -396,21 +396,31 @@ int dev_dax_probe(struct device *dev) { struct dev_dax *dev_dax = to_dev_dax(dev); struct dax_device *dax_dev = dev_dax->dax_dev; - struct resource *res = &dev_dax->region->res; + struct range *range = &dev_dax->range; + struct dev_pagemap *pgmap; struct inode *inode; struct cdev *cdev; void *addr; int rc;
/* 1:1 map region resource range to device-dax instance range */ - if (!devm_request_mem_region(dev, res->start, resource_size(res), + if (!devm_request_mem_region(dev, range->start, range_len(range), dev_name(dev))) { - dev_warn(dev, "could not reserve region %pR\n", res); + dev_warn(dev, "could not reserve range: %#llx - %#llx\n", + range->start, range->end); return -EBUSY; }
- dev_dax->pgmap.type = MEMORY_DEVICE_DEVDAX; - addr = devm_memremap_pages(dev, &dev_dax->pgmap); + pgmap = dev_dax->pgmap; + if (!pgmap) { + pgmap = devm_kzalloc(dev, sizeof(*pgmap), GFP_KERNEL); + if (!pgmap) + return -ENOMEM; + pgmap->res.start = range->start; + pgmap->res.end = range->end; + } + pgmap->type = MEMORY_DEVICE_DEVDAX; + addr = devm_memremap_pages(dev, pgmap); if (IS_ERR(addr)) return PTR_ERR(addr);
diff --git a/drivers/dax/hmem/hmem.c b/drivers/dax/hmem/hmem.c index b84fe17178d8..af82d6ba820a 100644 --- a/drivers/dax/hmem/hmem.c +++ b/drivers/dax/hmem/hmem.c @@ -8,7 +8,6 @@ static int dax_hmem_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; - struct dev_pagemap pgmap = { }; struct dax_region *dax_region; struct memregion_info *mri; struct dev_dax_data data; @@ -20,8 +19,6 @@ static int dax_hmem_probe(struct platform_device *pdev) return -ENOMEM;
mri = dev->platform_data; - memcpy(&pgmap.res, res, sizeof(*res)); - dax_region = alloc_dax_region(dev, pdev->id, res, mri->target_node, PMD_SIZE); if (!dax_region) @@ -30,7 +27,10 @@ static int dax_hmem_probe(struct platform_device *pdev) data = (struct dev_dax_data) { .dax_region = dax_region, .id = 0, - .pgmap = &pgmap, + .range = { + .start = res->start, + .end = res->end, + }, }; dev_dax = devm_create_dev_dax(&data); if (IS_ERR(dev_dax)) diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c index 275aa5f87399..5bb133df147d 100644 --- a/drivers/dax/kmem.c +++ b/drivers/dax/kmem.c @@ -22,7 +22,7 @@ static bool any_hotremove_failed; int dev_dax_kmem_probe(struct device *dev) { struct dev_dax *dev_dax = to_dev_dax(dev); - struct resource *res = &dev_dax->region->res; + struct range *range = &dev_dax->range; resource_size_t kmem_start; resource_size_t kmem_size; resource_size_t kmem_end; @@ -39,17 +39,17 @@ int dev_dax_kmem_probe(struct device *dev) */ numa_node = dev_dax->target_node; if (numa_node < 0) { - dev_warn(dev, "rejecting DAX region %pR with invalid node: %d\n", - res, numa_node); + dev_warn(dev, "rejecting DAX region with invalid node: %d\n", + numa_node); return -EINVAL; }
/* Hotplug starting at the beginning of the next block: */ - kmem_start = ALIGN(res->start, memory_block_size_bytes()); + kmem_start = ALIGN(range->start, memory_block_size_bytes());
- kmem_size = resource_size(res); + kmem_size = range_len(range); /* Adjust the size down to compensate for moving up kmem_start: */ - kmem_size -= kmem_start - res->start; + kmem_size -= kmem_start - range->start; /* Align the size down to cover only complete blocks: */ kmem_size &= ~(memory_block_size_bytes() - 1); kmem_end = kmem_start + kmem_size; diff --git a/drivers/dax/pmem/core.c b/drivers/dax/pmem/core.c index 08ee5947a49c..4fa81d3d2f65 100644 --- a/drivers/dax/pmem/core.c +++ b/drivers/dax/pmem/core.c @@ -63,6 +63,10 @@ struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys) .id = id, .pgmap = &pgmap, .subsys = subsys, + .range = { + .start = res.start, + .end = res.end, + }, }; dev_dax = devm_create_dev_dax(&data);
diff --git a/tools/testing/nvdimm/dax-dev.c b/tools/testing/nvdimm/dax-dev.c index 7e5d979e73cb..38d8e55c4a0d 100644 --- a/tools/testing/nvdimm/dax-dev.c +++ b/tools/testing/nvdimm/dax-dev.c @@ -9,12 +9,12 @@ phys_addr_t dax_pgoff_to_phys(struct dev_dax *dev_dax, pgoff_t pgoff, unsigned long size) { - struct resource *res = &dev_dax->region->res; + struct range *range = &dev_dax->range; phys_addr_t addr;
- addr = pgoff * PAGE_SIZE + res->start; - if (addr >= res->start && addr <= res->end) { - if (addr + size - 1 <= res->end) { + addr = pgoff * PAGE_SIZE + range->start; + if (addr >= range->start && addr <= range->end) { + if (addr + size - 1 <= range->end) { if (get_nfit_res(addr)) { struct page *page;
Several related issues around this unneeded attribute:
- The dax_kmem_res property allows the kmem driver to stash the adjusted resource range that was used for the hotplug operation, but that can be recalculated from the original base range.
- kmem is using an open coded release_resource() + kfree() when an idiomatic release_mem_region() is sufficient.
- The driver managed resource need only manage the busy flag. Other flags are of no concern to the kmem driver. In fact if kmem inherits some memory range that add_memory_driver_managed() rejects that is a memory-hotplug-core policy that the driver is in no position to override.
- The implementation trusts that failed remove_memory() results in the entire resource range remaining pinned busy. The driver need not make that layering violation assumption and just maintain the busy state in its local resource.
- The "Hot-remove not yet implemented." comment is stale since hotremove support is now included.
Cc: David Hildenbrand david@redhat.com Cc: Vishal Verma vishal.l.verma@intel.com Cc: Dave Hansen dave.hansen@linux.intel.com Cc: Pavel Tatashin pasha.tatashin@soleen.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- drivers/dax/dax-private.h | 3 - drivers/dax/kmem.c | 123 +++++++++++++++++++++------------------------ 2 files changed, 58 insertions(+), 68 deletions(-)
diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h index 6779f683671d..12a2dbc43b40 100644 --- a/drivers/dax/dax-private.h +++ b/drivers/dax/dax-private.h @@ -42,8 +42,6 @@ struct dax_region { * @dev - device core * @pgmap - pgmap for memmap setup / lifetime (driver owned) * @range: resource range for the instance - * @dax_mem_res: physical address range of hotadded DAX memory - * @dax_mem_name: name for hotadded DAX memory via add_memory_driver_managed() */ struct dev_dax { struct dax_region *region; @@ -52,7 +50,6 @@ struct dev_dax { struct device dev; struct dev_pagemap *pgmap; struct range range; - struct resource *dax_kmem_res; };
static inline u64 range_len(struct range *range) diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c index 5bb133df147d..77e25361fbeb 100644 --- a/drivers/dax/kmem.c +++ b/drivers/dax/kmem.c @@ -19,16 +19,24 @@ static const char *kmem_name; /* Set if any memory will remain added when the driver will be unloaded. */ static bool any_hotremove_failed;
+static struct range dax_kmem_range(struct dev_dax *dev_dax) +{ + struct range range; + + /* memory-block align the hotplug range */ + range.start = ALIGN(dev_dax->range.start, memory_block_size_bytes()); + range.end = ALIGN_DOWN(dev_dax->range.end + 1, + memory_block_size_bytes()) - 1; + return range; +} + int dev_dax_kmem_probe(struct device *dev) { struct dev_dax *dev_dax = to_dev_dax(dev); - struct range *range = &dev_dax->range; - resource_size_t kmem_start; - resource_size_t kmem_size; - resource_size_t kmem_end; - struct resource *new_res; - const char *new_res_name; - int numa_node; + struct range range = dax_kmem_range(dev_dax); + int numa_node = dev_dax->target_node; + struct resource *res; + char *res_name; int rc;
/* @@ -37,109 +45,94 @@ int dev_dax_kmem_probe(struct device *dev) * could be mixed in a node with faster memory, causing * unavoidable performance issues. */ - numa_node = dev_dax->target_node; if (numa_node < 0) { dev_warn(dev, "rejecting DAX region with invalid node: %d\n", numa_node); return -EINVAL; }
- /* Hotplug starting at the beginning of the next block: */ - kmem_start = ALIGN(range->start, memory_block_size_bytes()); - - kmem_size = range_len(range); - /* Adjust the size down to compensate for moving up kmem_start: */ - kmem_size -= kmem_start - range->start; - /* Align the size down to cover only complete blocks: */ - kmem_size &= ~(memory_block_size_bytes() - 1); - kmem_end = kmem_start + kmem_size; - - new_res_name = kstrdup(dev_name(dev), GFP_KERNEL); - if (!new_res_name) + res_name = kstrdup(dev_name(dev), GFP_KERNEL); + if (!res_name) return -ENOMEM;
- /* Region is permanently reserved if hotremove fails. */ - new_res = request_mem_region(kmem_start, kmem_size, new_res_name); - if (!new_res) { - dev_warn(dev, "could not reserve region [%pa-%pa]\n", - &kmem_start, &kmem_end); - kfree(new_res_name); + res = request_mem_region(range.start, range_len(&range), res_name); + if (!res) { + dev_warn(dev, "could not reserve region [%#llx-%#llx]\n", + range.start, range.end); + kfree(res_name); return -EBUSY; }
/* - * Set flags appropriate for System RAM. Leave ..._BUSY clear - * so that add_memory() can add a child resource. Do not - * inherit flags from the parent since it may set new flags - * unknown to us that will break add_memory() below. + * Temporarily clear busy to allow add_memory_driver_managed() + * to claim it. */ - new_res->flags = IORESOURCE_SYSTEM_RAM; + res->flags &= ~IORESOURCE_BUSY;
/* * Ensure that future kexec'd kernels will not treat this as RAM * automatically. */ - rc = add_memory_driver_managed(numa_node, new_res->start, - resource_size(new_res), kmem_name); + rc = add_memory_driver_managed(numa_node, res->start, + resource_size(res), kmem_name); + + res->flags |= IORESOURCE_BUSY; if (rc) { - release_resource(new_res); - kfree(new_res); - kfree(new_res_name); + release_mem_region(range.start, range_len(&range)); + kfree(res_name); return rc; } - dev_dax->dax_kmem_res = new_res; + + dev_set_drvdata(dev, res_name);
return 0; }
#ifdef CONFIG_MEMORY_HOTREMOVE -static int dev_dax_kmem_remove(struct device *dev) +static void dax_kmem_release(struct dev_dax *dev_dax) { - struct dev_dax *dev_dax = to_dev_dax(dev); - struct resource *res = dev_dax->dax_kmem_res; - resource_size_t kmem_start = res->start; - resource_size_t kmem_size = resource_size(res); - const char *res_name = res->name; int rc; + struct device *dev = &dev_dax->dev; + const char *res_name = dev_get_drvdata(dev); + struct range range = dax_kmem_range(dev_dax);
/* * We have one shot for removing memory, if some memory blocks were not * offline prior to calling this function remove_memory() will fail, and * there is no way to hotremove this memory until reboot because device - * unbind will succeed even if we return failure. + * unbind will proceed regardless of the remove_memory result. */ - rc = remove_memory(dev_dax->target_node, kmem_start, kmem_size); - if (rc) { - any_hotremove_failed = true; - dev_err(dev, - "DAX region %pR cannot be hotremoved until the next reboot\n", - res); - return rc; + rc = remove_memory(dev_dax->target_node, range.start, range_len(&range)); + if (rc == 0) { + release_mem_region(range.start, range_len(&range)); + dev_set_drvdata(dev, NULL); + kfree(res_name); + return; }
- /* Release and free dax resources */ - release_resource(res); - kfree(res); - kfree(res_name); - dev_dax->dax_kmem_res = NULL; - - return 0; + any_hotremove_failed = true; + dev_err(dev, "%#llx-%#llx cannot be hotremoved until the next reboot\n", + range.start, range.end); } #else -static int dev_dax_kmem_remove(struct device *dev) +static void dax_kmem_release(struct dev_dax *dev_dax) { /* - * Without hotremove purposely leak the request_mem_region() for the - * device-dax range and return '0' to ->remove() attempts. The removal - * of the device from the driver always succeeds, but the region is - * permanently pinned as reserved by the unreleased - * request_mem_region(). + * Without hotremove purposely leak the request_mem_region() for + * the device-dax range attempts. The removal of the device from + * the driver always succeeds, but the region is permanently + * pinned as reserved by the unreleased request_mem_region(). */ any_hotremove_failed = true; - return 0; } #endif /* CONFIG_MEMORY_HOTREMOVE */
+static int dev_dax_kmem_remove(struct device *dev) +{ + dax_kmem_release(to_dev_dax(dev)); + return 0; +} + static struct dax_device_driver device_dax_kmem_driver = { .drv = { .probe = dev_dax_kmem_probe,
In preparation for a facility that enables dax regions to be sub-divided, introduce infrastructure to track and allocate region capacity.
The new dax_region/available_size attribute is only enabled for volatile hmem devices, not pmem devices that are defined by nvdimm namespace boundaries. This is per Jeff's feedback the last time dynamic device-dax capacity allocation support was discussed.
Link: https://lore.kernel.org/linux-nvdimm/x49shpp3zn8.fsf@segfault.boston.devel.r... Cc: Vishal Verma vishal.l.verma@intel.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- drivers/dax/bus.c | 120 +++++++++++++++++++++++++++++++++++++++++---- drivers/dax/bus.h | 7 ++- drivers/dax/dax-private.h | 2 - drivers/dax/hmem/hmem.c | 7 +-- drivers/dax/pmem/core.c | 8 +-- 5 files changed, 121 insertions(+), 23 deletions(-)
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index 96bd64ba95a5..0a48ce378686 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -130,6 +130,11 @@ ATTRIBUTE_GROUPS(dax_drv);
static int dax_bus_match(struct device *dev, struct device_driver *drv);
+static bool is_static(struct dax_region *dax_region) +{ + return (dax_region->res.flags & IORESOURCE_DAX_STATIC) != 0; +} + static struct bus_type dax_bus_type = { .name = "dax", .uevent = dax_bus_uevent, @@ -185,7 +190,48 @@ static ssize_t align_show(struct device *dev, } static DEVICE_ATTR_RO(align);
+#define for_each_dax_region_resource(dax_region, res) \ + for (res = (dax_region)->res.child; res; res = res->sibling) + +static unsigned long long dax_region_avail_size(struct dax_region *dax_region) +{ + resource_size_t size = resource_size(&dax_region->res); + struct resource *res; + + device_lock_assert(dax_region->dev); + + for_each_dax_region_resource(dax_region, res) + size -= resource_size(res); + return size; +} + +static ssize_t available_size_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct dax_region *dax_region = dev_get_drvdata(dev); + unsigned long long size; + + device_lock(dev); + size = dax_region_avail_size(dax_region); + device_unlock(dev); + + return sprintf(buf, "%llu\n", size); +} +static DEVICE_ATTR_RO(available_size); + +static umode_t dax_region_visible(struct kobject *kobj, struct attribute *a, + int n) +{ + struct device *dev = container_of(kobj, struct device, kobj); + struct dax_region *dax_region = dev_get_drvdata(dev); + + if (is_static(dax_region) && a == &dev_attr_available_size.attr) + return 0; + return a->mode; +} + static struct attribute *dax_region_attributes[] = { + &dev_attr_available_size.attr, &dev_attr_region_size.attr, &dev_attr_align.attr, &dev_attr_id.attr, @@ -195,6 +241,7 @@ static struct attribute *dax_region_attributes[] = { static const struct attribute_group dax_region_attribute_group = { .name = "dax_region", .attrs = dax_region_attributes, + .is_visible = dax_region_visible, };
static const struct attribute_group *dax_region_attribute_groups[] = { @@ -226,7 +273,8 @@ static void dax_region_unregister(void *region) }
struct dax_region *alloc_dax_region(struct device *parent, int region_id, - struct resource *res, int target_node, unsigned int align) + struct resource *res, int target_node, unsigned int align, + unsigned long flags) { struct dax_region *dax_region;
@@ -249,12 +297,17 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id, return NULL;
dev_set_drvdata(parent, dax_region); - memcpy(&dax_region->res, res, sizeof(*res)); kref_init(&dax_region->kref); dax_region->id = region_id; dax_region->align = align; dax_region->dev = parent; dax_region->target_node = target_node; + dax_region->res = (struct resource) { + .start = res->start, + .end = res->end, + .flags = IORESOURCE_MEM | flags, + }; + if (sysfs_create_groups(&parent->kobj, dax_region_attribute_groups)) { kfree(dax_region); return NULL; @@ -267,6 +320,32 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id, } EXPORT_SYMBOL_GPL(alloc_dax_region);
+static int alloc_dev_dax_range(struct dev_dax *dev_dax, resource_size_t size) +{ + struct dax_region *dax_region = dev_dax->region; + struct resource *res = &dax_region->res; + struct device *dev = &dev_dax->dev; + struct resource *alloc; + + device_lock_assert(dax_region->dev); + + /* TODO: handle multiple allocations per region */ + if (res->child) + return -ENOMEM; + + alloc = __request_region(res, res->start, size, dev_name(dev), 0); + + if (!alloc) + return -ENOMEM; + + dev_dax->range = (struct range) { + .start = alloc->start, + .end = alloc->end, + }; + + return 0; +} + static ssize_t size_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -361,6 +440,15 @@ void kill_dev_dax(struct dev_dax *dev_dax) } EXPORT_SYMBOL_GPL(kill_dev_dax);
+static void free_dev_dax_range(struct dev_dax *dev_dax) +{ + struct dax_region *dax_region = dev_dax->region; + struct range *range = &dev_dax->range; + + device_lock_assert(dax_region->dev); + __release_region(&dax_region->res, range->start, range_len(range)); +} + static void dev_dax_release(struct device *dev) { struct dev_dax *dev_dax = to_dev_dax(dev); @@ -385,6 +473,7 @@ static void unregister_dev_dax(void *dev) dev_dbg(dev, "%s\n", __func__);
kill_dev_dax(dev_dax); + free_dev_dax_range(dev_dax); device_del(dev); put_device(dev); } @@ -397,7 +486,7 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) struct dev_dax *dev_dax; struct inode *inode; struct device *dev; - int rc = -ENOMEM; + int rc;
if (data->id < 0) return ERR_PTR(-EINVAL); @@ -406,11 +495,25 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) if (!dev_dax) return ERR_PTR(-ENOMEM);
+ dev_dax->region = dax_region; + dev = &dev_dax->dev; + device_initialize(dev); + dev_set_name(dev, "dax%d.%d", dax_region->id, data->id); + + rc = alloc_dev_dax_range(dev_dax, data->size); + if (rc) + goto err_range; + if (data->pgmap) { + dev_WARN_ONCE(parent, !is_static(dax_region), + "custom dev_pagemap requires a static dax_region\n"); + dev_dax->pgmap = kmemdup(data->pgmap, sizeof(struct dev_pagemap), GFP_KERNEL); - if (!dev_dax->pgmap) + if (!dev_dax->pgmap) { + rc = -ENOMEM; goto err_pgmap; + } }
/* @@ -427,12 +530,7 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) kill_dax(dax_dev);
/* from here on we're committed to teardown via dev_dax_release() */ - dev = &dev_dax->dev; - device_initialize(dev); - dev_dax->dax_dev = dax_dev; - dev_dax->region = dax_region; - dev_dax->range = data->range; dev_dax->target_node = dax_region->target_node; kref_get(&dax_region->kref);
@@ -444,7 +542,6 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) dev->class = dax_class; dev->parent = parent; dev->type = &dev_dax_type; - dev_set_name(dev, "dax%d.%d", dax_region->id, data->id);
rc = device_add(dev); if (rc) { @@ -458,9 +555,12 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) return ERR_PTR(rc);
return dev_dax; + err_alloc_dax: kfree(dev_dax->pgmap); err_pgmap: + free_dev_dax_range(dev_dax); +err_range: kfree(dev_dax);
return ERR_PTR(rc); diff --git a/drivers/dax/bus.h b/drivers/dax/bus.h index 4aeb36da83a4..44592a8cac0f 100644 --- a/drivers/dax/bus.h +++ b/drivers/dax/bus.h @@ -10,8 +10,11 @@ struct resource; struct dax_device; struct dax_region; void dax_region_put(struct dax_region *dax_region); + +#define IORESOURCE_DAX_STATIC (1UL << 0) struct dax_region *alloc_dax_region(struct device *parent, int region_id, - struct resource *res, int target_node, unsigned int align); + struct resource *res, int target_node, unsigned int align, + unsigned long flags);
enum dev_dax_subsys { DEV_DAX_BUS = 0, /* zeroed dev_dax_data picks this by default */ @@ -22,7 +25,7 @@ struct dev_dax_data { struct dax_region *dax_region; struct dev_pagemap *pgmap; enum dev_dax_subsys subsys; - struct range range; + resource_size_t size; int id; };
diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h index 12a2dbc43b40..99b1273bb232 100644 --- a/drivers/dax/dax-private.h +++ b/drivers/dax/dax-private.h @@ -22,7 +22,7 @@ void dax_bus_exit(void); * @kref: to pin while other agents have a need to do lookups * @dev: parent device backing this region * @align: allocation and mapping alignment for child dax devices - * @res: physical address range of the region + * @res: resource tree to track instance allocations */ struct dax_region { int id; diff --git a/drivers/dax/hmem/hmem.c b/drivers/dax/hmem/hmem.c index af82d6ba820a..e7b64539e23e 100644 --- a/drivers/dax/hmem/hmem.c +++ b/drivers/dax/hmem/hmem.c @@ -20,17 +20,14 @@ static int dax_hmem_probe(struct platform_device *pdev)
mri = dev->platform_data; dax_region = alloc_dax_region(dev, pdev->id, res, mri->target_node, - PMD_SIZE); + PMD_SIZE, 0); if (!dax_region) return -ENOMEM;
data = (struct dev_dax_data) { .dax_region = dax_region, .id = 0, - .range = { - .start = res->start, - .end = res->end, - }, + .size = resource_size(res), }; dev_dax = devm_create_dev_dax(&data); if (IS_ERR(dev_dax)) diff --git a/drivers/dax/pmem/core.c b/drivers/dax/pmem/core.c index 4fa81d3d2f65..4fe700884338 100644 --- a/drivers/dax/pmem/core.c +++ b/drivers/dax/pmem/core.c @@ -54,7 +54,8 @@ struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys) memcpy(&res, &pgmap.res, sizeof(res)); res.start += offset; dax_region = alloc_dax_region(dev, region_id, &res, - nd_region->target_node, le32_to_cpu(pfn_sb->align)); + nd_region->target_node, le32_to_cpu(pfn_sb->align), + IORESOURCE_DAX_STATIC); if (!dax_region) return ERR_PTR(-ENOMEM);
@@ -63,10 +64,7 @@ struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys) .id = id, .pgmap = &pgmap, .subsys = subsys, - .range = { - .start = res.start, - .end = res.end, - }, + .size = resource_size(&res), }; dev_dax = devm_create_dev_dax(&data);
Add a seed device concept for dynamic dax regions to be able to split the region amongst multiple sub-instances. The seed device, similar to libnvdimm seed devices, is a device that starts with zero capacity allocated and unbound to a driver. In contrast to libnvdimm seed devices explicit 'create' and 'delete' interfaces are added to the region to trigger seeds to be created and unused devices to be reclaimed. The explicit create and delete replaces implicit create as a side effect of probe and implicit delete when writing 0 to the size that libnvdimm implements.
Delete can be performed on any 0-sized and idle device. This avoids the gymnastics of needing to move device_unregister() to its own async context. Specifically, it avoids the deadlock of deleting a device via one of its own attributes. It is also less surprising to userspace which never sees an extra device it did not request.
For now just add the device creation, teardown, and ->probe() prevention. A later patch will arrange for the 'dax/size' attribute to be writable to allocate capacity from the region.
Cc: Vishal Verma vishal.l.verma@intel.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- drivers/dax/bus.c | 317 ++++++++++++++++++++++++++++++++++++++++----- drivers/dax/bus.h | 4 - drivers/dax/dax-private.h | 9 + drivers/dax/device.c | 12 +- drivers/dax/hmem/hmem.c | 2 drivers/dax/kmem.c | 14 +- drivers/dax/pmem/compat.c | 2 7 files changed, 304 insertions(+), 56 deletions(-)
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index 0a48ce378686..dce9413a4394 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -135,10 +135,46 @@ static bool is_static(struct dax_region *dax_region) return (dax_region->res.flags & IORESOURCE_DAX_STATIC) != 0; }
+static int dax_bus_probe(struct device *dev) +{ + struct dax_device_driver *dax_drv = to_dax_drv(dev->driver); + struct dev_dax *dev_dax = to_dev_dax(dev); + struct dax_region *dax_region = dev_dax->region; + struct range *range = &dev_dax->range; + int rc; + + if (range_len(range) == 0 || dev_dax->id < 0) + return -ENXIO; + + rc = dax_drv->probe(dev_dax); + + if (rc || is_static(dax_region)) + return rc; + + /* + * Track new seed creation only after successful probe of the + * previous seed. + */ + if (dax_region->seed == dev) + dax_region->seed = NULL; + + return 0; +} + +static int dax_bus_remove(struct device *dev) +{ + struct dax_device_driver *dax_drv = to_dax_drv(dev->driver); + struct dev_dax *dev_dax = to_dev_dax(dev); + + return dax_drv->remove(dev_dax); +} + static struct bus_type dax_bus_type = { .name = "dax", .uevent = dax_bus_uevent, .match = dax_bus_match, + .probe = dax_bus_probe, + .remove = dax_bus_remove, .drv_groups = dax_drv_groups, };
@@ -219,14 +255,216 @@ static ssize_t available_size_show(struct device *dev, } static DEVICE_ATTR_RO(available_size);
+static ssize_t seed_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct dax_region *dax_region = dev_get_drvdata(dev); + struct device *seed; + ssize_t rc; + + if (is_static(dax_region)) + return -EINVAL; + + device_lock(dev); + seed = dax_region->seed; + rc = sprintf(buf, "%s\n", seed ? dev_name(seed) : ""); + device_unlock(dev); + + return rc; +} +static DEVICE_ATTR_RO(seed); + +static ssize_t create_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct dax_region *dax_region = dev_get_drvdata(dev); + struct device *youngest; + ssize_t rc; + + if (is_static(dax_region)) + return -EINVAL; + + device_lock(dev); + youngest = dax_region->youngest; + rc = sprintf(buf, "%s\n", youngest ? dev_name(youngest) : ""); + device_unlock(dev); + + return rc; +} + +static ssize_t create_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t len) +{ + struct dax_region *dax_region = dev_get_drvdata(dev); + unsigned long long avail; + ssize_t rc; + int val; + + if (is_static(dax_region)) + return -EINVAL; + + rc = kstrtoint(buf, 0, &val); + if (rc) + return rc; + if (val != 1) + return -EINVAL; + + device_lock(dev); + avail = dax_region_avail_size(dax_region); + if (avail == 0) + rc = -ENOSPC; + else { + struct dev_dax_data data = { + .dax_region = dax_region, + .size = 0, + .id = -1, + }; + struct dev_dax *dev_dax = devm_create_dev_dax(&data); + + if (IS_ERR(dev_dax)) + rc = PTR_ERR(dev_dax); + else { + /* + * In support of crafting multiple new devices + * simultaneously multiple seeds can be created, + * but only the first one that has not been + * successfully bound is tracked as the region + * seed. + */ + if (!dax_region->seed) + dax_region->seed = &dev_dax->dev; + dax_region->youngest = &dev_dax->dev; + rc = len; + } + } + device_unlock(dev); + + return rc; +} +static DEVICE_ATTR_RW(create); + +void kill_dev_dax(struct dev_dax *dev_dax) +{ + struct dax_device *dax_dev = dev_dax->dax_dev; + struct inode *inode = dax_inode(dax_dev); + + kill_dax(dax_dev); + unmap_mapping_range(inode->i_mapping, 0, 0, 1); +} +EXPORT_SYMBOL_GPL(kill_dev_dax); + +static void free_dev_dax_range(struct dev_dax *dev_dax) +{ + struct dax_region *dax_region = dev_dax->region; + struct range *range = &dev_dax->range; + + device_lock_assert(dax_region->dev); + if (range_len(range)) + __release_region(&dax_region->res, range->start, + range_len(range)); +} + +static void unregister_dev_dax(void *dev) +{ + struct dev_dax *dev_dax = to_dev_dax(dev); + + dev_dbg(dev, "%s\n", __func__); + + kill_dev_dax(dev_dax); + free_dev_dax_range(dev_dax); + device_del(dev); + put_device(dev); +} + +/* a return value >= 0 indicates this invocation invalidated the id */ +static int __free_dev_dax_id(struct dev_dax *dev_dax) +{ + struct dax_region *dax_region = dev_dax->region; + struct device *dev = &dev_dax->dev; + int rc = dev_dax->id; + + device_lock_assert(dev); + + if (is_static(dax_region) || dev_dax->id < 0) + return -1; + ida_free(&dax_region->ida, dev_dax->id); + dev_dax->id = -1; + return rc; +} + +static int free_dev_dax_id(struct dev_dax *dev_dax) +{ + struct device *dev = &dev_dax->dev; + int rc; + + device_lock(dev); + rc = __free_dev_dax_id(dev_dax); + device_unlock(dev); + return rc; +} + +static ssize_t delete_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t len) +{ + struct dax_region *dax_region = dev_get_drvdata(dev); + struct dev_dax *dev_dax; + struct device *victim; + bool do_del = false; + int rc; + + if (is_static(dax_region)) + return -EINVAL; + + victim = device_find_child_by_name(dax_region->dev, buf); + if (!victim) + return -ENXIO; + + device_lock(dev); + device_lock(victim); + dev_dax = to_dev_dax(victim); + if (victim->driver || range_len(&dev_dax->range)) + rc = -EBUSY; + else { + /* + * Invalidate the device so it does not become active + * again, but always preserve device-id-0 so that + * /sys/bus/dax/ is guaranteed to be populated while any + * dax_region is registered. + */ + if (dev_dax->id > 0) { + do_del = __free_dev_dax_id(dev_dax) >= 0; + rc = len; + if (dax_region->seed == victim) + dax_region->seed = NULL; + if (dax_region->youngest == victim) + dax_region->youngest = NULL; + } else + rc = -EBUSY; + } + device_unlock(victim); + + /* won the race to invalidate the device, clean it up */ + if (do_del) + devm_release_action(dev, unregister_dev_dax, victim); + device_unlock(dev); + put_device(victim); + + return rc; +} +static DEVICE_ATTR_WO(delete); + static umode_t dax_region_visible(struct kobject *kobj, struct attribute *a, int n) { struct device *dev = container_of(kobj, struct device, kobj); struct dax_region *dax_region = dev_get_drvdata(dev);
- if (is_static(dax_region) && a == &dev_attr_available_size.attr) - return 0; + if (is_static(dax_region)) + if (a == &dev_attr_available_size.attr + || a == &dev_attr_create.attr + || a == &dev_attr_seed.attr + || a == &dev_attr_delete.attr) + return 0; return a->mode; }
@@ -234,6 +472,9 @@ static struct attribute *dax_region_attributes[] = { &dev_attr_available_size.attr, &dev_attr_region_size.attr, &dev_attr_align.attr, + &dev_attr_create.attr, + &dev_attr_seed.attr, + &dev_attr_delete.attr, &dev_attr_id.attr, NULL, }; @@ -302,6 +543,7 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id, dax_region->align = align; dax_region->dev = parent; dax_region->target_node = target_node; + ida_init(&dax_region->ida); dax_region->res = (struct resource) { .start = res->start, .end = res->end, @@ -329,6 +571,15 @@ static int alloc_dev_dax_range(struct dev_dax *dev_dax, resource_size_t size)
device_lock_assert(dax_region->dev);
+ /* handle the seed alloc special case */ + if (!size) { + dev_dax->range = (struct range) { + .start = res->start, + .end = res->start - 1, + }; + return 0; + } + /* TODO: handle multiple allocations per region */ if (res->child) return -ENOMEM; @@ -430,33 +681,15 @@ static const struct attribute_group *dax_attribute_groups[] = { NULL, };
-void kill_dev_dax(struct dev_dax *dev_dax) -{ - struct dax_device *dax_dev = dev_dax->dax_dev; - struct inode *inode = dax_inode(dax_dev); - - kill_dax(dax_dev); - unmap_mapping_range(inode->i_mapping, 0, 0, 1); -} -EXPORT_SYMBOL_GPL(kill_dev_dax); - -static void free_dev_dax_range(struct dev_dax *dev_dax) -{ - struct dax_region *dax_region = dev_dax->region; - struct range *range = &dev_dax->range; - - device_lock_assert(dax_region->dev); - __release_region(&dax_region->res, range->start, range_len(range)); -} - static void dev_dax_release(struct device *dev) { struct dev_dax *dev_dax = to_dev_dax(dev); struct dax_region *dax_region = dev_dax->region; struct dax_device *dax_dev = dev_dax->dax_dev;
- dax_region_put(dax_region); put_dax(dax_dev); + free_dev_dax_id(dev_dax); + dax_region_put(dax_region); kfree(dev_dax->pgmap); kfree(dev_dax); } @@ -466,18 +699,6 @@ static const struct device_type dev_dax_type = { .groups = dax_attribute_groups, };
-static void unregister_dev_dax(void *dev) -{ - struct dev_dax *dev_dax = to_dev_dax(dev); - - dev_dbg(dev, "%s\n", __func__); - - kill_dev_dax(dev_dax); - free_dev_dax_range(dev_dax); - device_del(dev); - put_device(dev); -} - struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) { struct dax_region *dax_region = data->dax_region; @@ -488,17 +709,35 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) struct device *dev; int rc;
- if (data->id < 0) - return ERR_PTR(-EINVAL); - dev_dax = kzalloc(sizeof(*dev_dax), GFP_KERNEL); if (!dev_dax) return ERR_PTR(-ENOMEM);
+ if (is_static(dax_region)) { + if (dev_WARN_ONCE(parent, data->id < 0, + "dynamic id specified to static region\n")) { + rc = -EINVAL; + goto err_id; + } + + dev_dax->id = data->id; + } else { + if (dev_WARN_ONCE(parent, data->id >= 0, + "static id specified to dynamic region\n")) { + rc = -EINVAL; + goto err_id; + } + + rc = ida_alloc(&dax_region->ida, GFP_KERNEL); + if (rc < 0) + goto err_id; + dev_dax->id = rc; + } + dev_dax->region = dax_region; dev = &dev_dax->dev; device_initialize(dev); - dev_set_name(dev, "dax%d.%d", dax_region->id, data->id); + dev_set_name(dev, "dax%d.%d", dax_region->id, dev_dax->id);
rc = alloc_dev_dax_range(dev_dax, data->size); if (rc) @@ -561,6 +800,8 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) err_pgmap: free_dev_dax_range(dev_dax); err_range: + free_dev_dax_id(dev_dax); +err_id: kfree(dev_dax);
return ERR_PTR(rc); diff --git a/drivers/dax/bus.h b/drivers/dax/bus.h index 44592a8cac0f..da27ea70a19a 100644 --- a/drivers/dax/bus.h +++ b/drivers/dax/bus.h @@ -38,6 +38,8 @@ struct dax_device_driver { struct device_driver drv; struct list_head ids; int match_always; + int (*probe)(struct dev_dax *dev); + int (*remove)(struct dev_dax *dev); };
int __dax_driver_register(struct dax_device_driver *dax_drv, @@ -48,7 +50,7 @@ void dax_driver_unregister(struct dax_device_driver *dax_drv); void kill_dev_dax(struct dev_dax *dev_dax);
#if IS_ENABLED(CONFIG_DEV_DAX_PMEM_COMPAT) -int dev_dax_probe(struct device *dev); +int dev_dax_probe(struct dev_dax *dev_dax); #endif
/* diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h index 99b1273bb232..b81a1494d82b 100644 --- a/drivers/dax/dax-private.h +++ b/drivers/dax/dax-private.h @@ -7,6 +7,7 @@
#include <linux/device.h> #include <linux/cdev.h> +#include <linux/idr.h>
/* private routines between core files */ struct dax_device; @@ -22,7 +23,10 @@ void dax_bus_exit(void); * @kref: to pin while other agents have a need to do lookups * @dev: parent device backing this region * @align: allocation and mapping alignment for child dax devices + * @ida: instance id allocator * @res: resource tree to track instance allocations + * @seed: allow userspace to find the first unbound seed device + * @youngest: allow userspace to find the most recently created device */ struct dax_region { int id; @@ -30,7 +34,10 @@ struct dax_region { struct kref kref; struct device *dev; unsigned int align; + struct ida ida; struct resource res; + struct device *seed; + struct device *youngest; };
/** @@ -39,6 +46,7 @@ struct dax_region { * @region - parent region * @dax_dev - core dax functionality * @target_node: effective numa node if dev_dax memory range is onlined + * @id: ida allocated id * @dev - device core * @pgmap - pgmap for memmap setup / lifetime (driver owned) * @range: resource range for the instance @@ -47,6 +55,7 @@ struct dev_dax { struct dax_region *region; struct dax_device *dax_dev; int target_node; + int id; struct device dev; struct dev_pagemap *pgmap; struct range range; diff --git a/drivers/dax/device.c b/drivers/dax/device.c index a86b2c9788c5..5496331f6eb6 100644 --- a/drivers/dax/device.c +++ b/drivers/dax/device.c @@ -392,11 +392,11 @@ static void dev_dax_kill(void *dev_dax) kill_dev_dax(dev_dax); }
-int dev_dax_probe(struct device *dev) +int dev_dax_probe(struct dev_dax *dev_dax) { - struct dev_dax *dev_dax = to_dev_dax(dev); struct dax_device *dax_dev = dev_dax->dax_dev; struct range *range = &dev_dax->range; + struct device *dev = &dev_dax->dev; struct dev_pagemap *pgmap; struct inode *inode; struct cdev *cdev; @@ -446,17 +446,15 @@ int dev_dax_probe(struct device *dev) } EXPORT_SYMBOL_GPL(dev_dax_probe);
-static int dev_dax_remove(struct device *dev) +static int dev_dax_remove(struct dev_dax *dev_dax) { /* all probe actions are unwound by devm */ return 0; }
static struct dax_device_driver device_dax_driver = { - .drv = { - .probe = dev_dax_probe, - .remove = dev_dax_remove, - }, + .probe = dev_dax_probe, + .remove = dev_dax_remove, .match_always = 1, };
diff --git a/drivers/dax/hmem/hmem.c b/drivers/dax/hmem/hmem.c index e7b64539e23e..aa260009dfc7 100644 --- a/drivers/dax/hmem/hmem.c +++ b/drivers/dax/hmem/hmem.c @@ -26,7 +26,7 @@ static int dax_hmem_probe(struct platform_device *pdev)
data = (struct dev_dax_data) { .dax_region = dax_region, - .id = 0, + .id = -1, .size = resource_size(res), }; dev_dax = devm_create_dev_dax(&data); diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c index 77e25361fbeb..b1be8a53b26a 100644 --- a/drivers/dax/kmem.c +++ b/drivers/dax/kmem.c @@ -30,11 +30,11 @@ static struct range dax_kmem_range(struct dev_dax *dev_dax) return range; }
-int dev_dax_kmem_probe(struct device *dev) +int dev_dax_kmem_probe(struct dev_dax *dev_dax) { - struct dev_dax *dev_dax = to_dev_dax(dev); struct range range = dax_kmem_range(dev_dax); int numa_node = dev_dax->target_node; + struct device *dev = &dev_dax->dev; struct resource *res; char *res_name; int rc; @@ -127,17 +127,15 @@ static void dax_kmem_release(struct dev_dax *dev_dax) } #endif /* CONFIG_MEMORY_HOTREMOVE */
-static int dev_dax_kmem_remove(struct device *dev) +static int dev_dax_kmem_remove(struct dev_dax *dev_dax) { - dax_kmem_release(to_dev_dax(dev)); + dax_kmem_release(dev_dax); return 0; }
static struct dax_device_driver device_dax_kmem_driver = { - .drv = { - .probe = dev_dax_kmem_probe, - .remove = dev_dax_kmem_remove, - }, + .probe = dev_dax_kmem_probe, + .remove = dev_dax_kmem_remove, };
static int __init dax_kmem_init(void) diff --git a/drivers/dax/pmem/compat.c b/drivers/dax/pmem/compat.c index d7b15e6f30c5..863c114fd88c 100644 --- a/drivers/dax/pmem/compat.c +++ b/drivers/dax/pmem/compat.c @@ -22,7 +22,7 @@ static int dax_pmem_compat_probe(struct device *dev) return -ENOMEM;
device_lock(&dev_dax->dev); - rc = dev_dax_probe(&dev_dax->dev); + rc = dev_dax_probe(dev_dax); device_unlock(&dev_dax->dev);
devres_close_group(&dev_dax->dev, dev_dax);
Use sysfs_streq() in device_find_child_by_name() to allow it to use a sysfs input string that might contain a trailing newline.
The other "device by name" interfaces, {bus,driver,class}_find_device_by_name(), already account for sysfs strings.
Cc: "Rafael J. Wysocki" rafael@kernel.org Reviewed-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Dan Williams dan.j.williams@intel.com --- drivers/base/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/base/core.c b/drivers/base/core.c index 2169c5132558..231189dd6599 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -3328,7 +3328,7 @@ struct device *device_find_child_by_name(struct device *parent,
klist_iter_init(&parent->p->klist_children, &i); while ((child = next_device(&i))) - if (!strcmp(dev_name(child), name) && get_device(child)) + if (sysfs_streq(dev_name(child), name) && get_device(child)) break; klist_iter_exit(&i); return child;
Make the device-dax 'size' attribute writable to allow capacity to be split between multiple instances in a region. The intended consumers of this capability are users that want to split a scarce memory resource between device-dax and System-RAM access, or users that want to have multiple security domains for a large region.
By default the hmem instance provider allocates an entire region to the first instance. The process of creating a new instance (assuming a region-id of 0) is find the region and trigger the 'create' attribute which yields an empty instance to configure. For example:
cd /sys/bus/dax/devices echo dax0.0 > dax0.0/driver/unbind echo $new_size > dax0.0/size echo 1 > $(readlink -f dax0.0)../dax_region/create seed=$(cat $(readlink -f dax0.0)../dax_region/seed) echo $new_size > $seed/size echo dax0.0 > ../drivers/{device_dax,kmem}/bind echo dax0.1 > ../drivers/{device_dax,kmem}/bind
Instances can be destroyed by:
echo $device > $(readlink -f $device)../dax_region/delete
Cc: Vishal Verma vishal.l.verma@intel.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- drivers/dax/bus.c | 161 ++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 152 insertions(+), 9 deletions(-)
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index dce9413a4394..53d07f2f1285 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -6,6 +6,7 @@ #include <linux/list.h> #include <linux/slab.h> #include <linux/dax.h> +#include <linux/io.h> #include "dax-private.h" #include "bus.h"
@@ -562,7 +563,8 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id, } EXPORT_SYMBOL_GPL(alloc_dax_region);
-static int alloc_dev_dax_range(struct dev_dax *dev_dax, resource_size_t size) +static int alloc_dev_dax_range(struct dev_dax *dev_dax, u64 start, + resource_size_t size) { struct dax_region *dax_region = dev_dax->region; struct resource *res = &dax_region->res; @@ -580,12 +582,7 @@ static int alloc_dev_dax_range(struct dev_dax *dev_dax, resource_size_t size) return 0; }
- /* TODO: handle multiple allocations per region */ - if (res->child) - return -ENOMEM; - - alloc = __request_region(res, res->start, size, dev_name(dev), 0); - + alloc = __request_region(res, start, size, dev_name(dev), 0); if (!alloc) return -ENOMEM;
@@ -597,6 +594,29 @@ static int alloc_dev_dax_range(struct dev_dax *dev_dax, resource_size_t size) return 0; }
+static int adjust_dev_dax_range(struct dev_dax *dev_dax, struct resource *res, resource_size_t size) +{ + struct dax_region *dax_region = dev_dax->region; + struct range *range = &dev_dax->range; + int rc = 0; + + device_lock_assert(dax_region->dev); + + if (size) + rc = adjust_resource(res, range->start, size); + else + __release_region(&dax_region->res, range->start, range_len(range)); + if (rc) + return rc; + + dev_dax->range = (struct range) { + .start = range->start, + .end = range->start + size - 1, + }; + + return 0; +} + static ssize_t size_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -605,7 +625,127 @@ static ssize_t size_show(struct device *dev,
return sprintf(buf, "%llu\n", size); } -static DEVICE_ATTR_RO(size); + +static bool alloc_is_aligned(struct dax_region *dax_region, + resource_size_t size) +{ + /* + * The minimum mapping granularity for a device instance is a + * single subsection, unless the arch says otherwise. + */ + return IS_ALIGNED(size, max_t(unsigned long, dax_region->align, + memremap_compat_align())); +} + +static int dev_dax_shrink(struct dev_dax *dev_dax, resource_size_t size) +{ + struct dax_region *dax_region = dev_dax->region; + struct range *range = &dev_dax->range; + struct resource *res, *adjust = NULL; + struct device *dev = &dev_dax->dev; + + for_each_dax_region_resource(dax_region, res) + if (strcmp(res->name, dev_name(dev)) == 0 + && res->start == range->start) { + adjust = res; + break; + } + + if (dev_WARN_ONCE(dev, !adjust, "failed to find matching resource\n")) + return -ENXIO; + return adjust_dev_dax_range(dev_dax, adjust, size); +} + +static ssize_t dev_dax_resize(struct dax_region *dax_region, + struct dev_dax *dev_dax, resource_size_t size) +{ + resource_size_t avail = dax_region_avail_size(dax_region), to_alloc; + resource_size_t dev_size = range_len(&dev_dax->range); + struct resource *region_res = &dax_region->res; + struct device *dev = &dev_dax->dev; + const char *name = dev_name(dev); + struct resource *res, *first; + + if (dev->driver) + return -EBUSY; + if (size == dev_size) + return 0; + if (size > dev_size && size - dev_size > avail) + return -ENOSPC; + if (size < dev_size) + return dev_dax_shrink(dev_dax, size); + + to_alloc = size - dev_size; + if (dev_WARN_ONCE(dev, !alloc_is_aligned(dax_region, to_alloc), + "resize of %pa misaligned\n", &to_alloc)) + return -ENXIO; + + /* + * Expand the device into the unused portion of the region. This + * may involve adjusting the end of an existing resource, or + * allocating a new resource. + */ + first = region_res->child; + if (!first) + return alloc_dev_dax_range(dev_dax, dax_region->res.start, to_alloc); + for (res = first; to_alloc && res; res = res->sibling) { + struct resource *next = res->sibling; + resource_size_t free; + + /* space at the beginning of the region */ + free = 0; + if (res == first && res->start > dax_region->res.start) + free = res->start - dax_region->res.start; + if (free >= to_alloc && dev_size == 0) + return alloc_dev_dax_range(dev_dax, dax_region->res.start, to_alloc); + + free = 0; + /* space between allocations */ + if (next && next->start > res->end + 1) + free = next->start - res->end + 1; + + /* space at the end of the region */ + if (free < to_alloc && !next && res->end < region_res->end) + free = region_res->end - res->end; + + if (free >= to_alloc && strcmp(name, res->name) == 0) + return adjust_dev_dax_range(dev_dax, res, resource_size(res) + to_alloc); + else if (free >= to_alloc && dev_size == 0) + return alloc_dev_dax_range(dev_dax, res->end + 1, to_alloc); + } + return -ENOSPC; +} + +static ssize_t size_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t len) +{ + ssize_t rc; + unsigned long long val; + struct dev_dax *dev_dax = to_dev_dax(dev); + struct dax_region *dax_region = dev_dax->region; + + rc = kstrtoull(buf, 0, &val); + if (rc) + return rc; + + if (!alloc_is_aligned(dax_region, val)) { + dev_dbg(dev, "%s: size: %lld misaligned\n", __func__, val); + return -EINVAL; + } + + device_lock(dax_region->dev); + if (!dax_region->dev->driver) { + device_unlock(dax_region->dev); + return -ENXIO; + } + device_lock(dev); + rc = dev_dax_resize(dax_region, dev_dax, val); + device_unlock(dev); + device_unlock(dax_region->dev); + + return rc == 0 ? len : rc; +} +static DEVICE_ATTR_RW(size);
static int dev_dax_target_node(struct dev_dax *dev_dax) { @@ -654,11 +794,14 @@ static umode_t dev_dax_visible(struct kobject *kobj, struct attribute *a, int n) { struct device *dev = container_of(kobj, struct device, kobj); struct dev_dax *dev_dax = to_dev_dax(dev); + struct dax_region *dax_region = dev_dax->region;
if (a == &dev_attr_target_node.attr && dev_dax_target_node(dev_dax) < 0) return 0; if (a == &dev_attr_numa_node.attr && !IS_ENABLED(CONFIG_NUMA)) return 0; + if (a == &dev_attr_size.attr && is_static(dax_region)) + return 0444; return a->mode; }
@@ -739,7 +882,7 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) device_initialize(dev); dev_set_name(dev, "dax%d.%d", dax_region->id, dev_dax->id);
- rc = alloc_dev_dax_range(dev_dax, data->size); + rc = alloc_dev_dax_range(dev_dax, dax_region->res.start, data->size); if (rc) goto err_range;
The 'struct resource' in 'struct dev_pagemap' is only used for holding resource span information. The other fields, 'name', 'flags', 'desc', 'parent', 'sibling', and 'child' are all unused wasted space.
This is in preparation for introducing a multi-range extension of devm_memremap_pages().
The bulk of this change is unwinding all the places internal to libnvdimm that used 'struct resource' unnecessarily.
P2PDMA had a minor usage of the flags field, but only to report failures with "%pR". That is replaced with an open coded print of the range.
Cc: Paul Mackerras paulus@ozlabs.org Cc: Michael Ellerman mpe@ellerman.id.au Cc: Benjamin Herrenschmidt benh@kernel.crashing.org Cc: Dan Williams dan.j.williams@intel.com Cc: Vishal Verma vishal.l.verma@intel.com Cc: Dave Jiang dave.jiang@intel.com Cc: Ben Skeggs bskeggs@redhat.com Cc: David Airlie airlied@linux.ie Cc: Daniel Vetter daniel@ffwll.ch Cc: Ira Weiny ira.weiny@intel.com Cc: Jason Gunthorpe jgg@mellanox.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- arch/powerpc/kvm/book3s_hv_uvmem.c | 13 +++-- drivers/dax/bus.c | 10 ++-- drivers/dax/bus.h | 2 - drivers/dax/dax-private.h | 5 -- drivers/dax/device.c | 3 - drivers/dax/hmem/hmem.c | 5 ++ drivers/dax/pmem/core.c | 12 ++--- drivers/gpu/drm/nouveau/nouveau_dmem.c | 14 +++--- drivers/nvdimm/badrange.c | 26 +++++------ drivers/nvdimm/claim.c | 13 +++-- drivers/nvdimm/nd.h | 3 + drivers/nvdimm/pfn_devs.c | 12 ++--- drivers/nvdimm/pmem.c | 26 ++++++----- drivers/nvdimm/region.c | 21 +++++---- drivers/pci/p2pdma.c | 11 ++--- include/linux/memremap.h | 5 +- include/linux/range.h | 6 ++ lib/test_hmm.c | 14 +++--- mm/memremap.c | 77 ++++++++++++++++---------------- tools/testing/nvdimm/test/iomap.c | 2 - 20 files changed, 147 insertions(+), 133 deletions(-)
diff --git a/arch/powerpc/kvm/book3s_hv_uvmem.c b/arch/powerpc/kvm/book3s_hv_uvmem.c index 7705d5557239..29ec555055c2 100644 --- a/arch/powerpc/kvm/book3s_hv_uvmem.c +++ b/arch/powerpc/kvm/book3s_hv_uvmem.c @@ -687,9 +687,9 @@ static struct page *kvmppc_uvmem_get_page(unsigned long gpa, struct kvm *kvm) struct kvmppc_uvmem_page_pvt *pvt; unsigned long pfn_last, pfn_first;
- pfn_first = kvmppc_uvmem_pgmap.res.start >> PAGE_SHIFT; + pfn_first = kvmppc_uvmem_pgmap.range.start >> PAGE_SHIFT; pfn_last = pfn_first + - (resource_size(&kvmppc_uvmem_pgmap.res) >> PAGE_SHIFT); + (range_len(&kvmppc_uvmem_pgmap.range) >> PAGE_SHIFT);
spin_lock(&kvmppc_uvmem_bitmap_lock); bit = find_first_zero_bit(kvmppc_uvmem_bitmap, @@ -1007,7 +1007,7 @@ static vm_fault_t kvmppc_uvmem_migrate_to_ram(struct vm_fault *vmf) static void kvmppc_uvmem_page_free(struct page *page) { unsigned long pfn = page_to_pfn(page) - - (kvmppc_uvmem_pgmap.res.start >> PAGE_SHIFT); + (kvmppc_uvmem_pgmap.range.start >> PAGE_SHIFT); struct kvmppc_uvmem_page_pvt *pvt;
spin_lock(&kvmppc_uvmem_bitmap_lock); @@ -1170,7 +1170,8 @@ int kvmppc_uvmem_init(void) }
kvmppc_uvmem_pgmap.type = MEMORY_DEVICE_PRIVATE; - kvmppc_uvmem_pgmap.res = *res; + kvmppc_uvmem_pgmap.range.start = res->start; + kvmppc_uvmem_pgmap.range.end = res->end; kvmppc_uvmem_pgmap.ops = &kvmppc_uvmem_ops; /* just one global instance: */ kvmppc_uvmem_pgmap.owner = &kvmppc_uvmem_pgmap; @@ -1205,7 +1206,7 @@ void kvmppc_uvmem_free(void) return;
memunmap_pages(&kvmppc_uvmem_pgmap); - release_mem_region(kvmppc_uvmem_pgmap.res.start, - resource_size(&kvmppc_uvmem_pgmap.res)); + release_mem_region(kvmppc_uvmem_pgmap.range.start, + range_len(&kvmppc_uvmem_pgmap.range)); kfree(kvmppc_uvmem_bitmap); } diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index 53d07f2f1285..00fa73a8dfb4 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -515,7 +515,7 @@ static void dax_region_unregister(void *region) }
struct dax_region *alloc_dax_region(struct device *parent, int region_id, - struct resource *res, int target_node, unsigned int align, + struct range *range, int target_node, unsigned int align, unsigned long flags) { struct dax_region *dax_region; @@ -530,8 +530,8 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id, return NULL; }
- if (!IS_ALIGNED(res->start, align) - || !IS_ALIGNED(resource_size(res), align)) + if (!IS_ALIGNED(range->start, align) + || !IS_ALIGNED(range_len(range), align)) return NULL;
dax_region = kzalloc(sizeof(*dax_region), GFP_KERNEL); @@ -546,8 +546,8 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id, dax_region->target_node = target_node; ida_init(&dax_region->ida); dax_region->res = (struct resource) { - .start = res->start, - .end = res->end, + .start = range->start, + .end = range->end, .flags = IORESOURCE_MEM | flags, };
diff --git a/drivers/dax/bus.h b/drivers/dax/bus.h index da27ea70a19a..72b92f95509f 100644 --- a/drivers/dax/bus.h +++ b/drivers/dax/bus.h @@ -13,7 +13,7 @@ void dax_region_put(struct dax_region *dax_region);
#define IORESOURCE_DAX_STATIC (1UL << 0) struct dax_region *alloc_dax_region(struct device *parent, int region_id, - struct resource *res, int target_node, unsigned int align, + struct range *range, int target_node, unsigned int align, unsigned long flags);
enum dev_dax_subsys { diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h index b81a1494d82b..0cbb2ec81ca7 100644 --- a/drivers/dax/dax-private.h +++ b/drivers/dax/dax-private.h @@ -61,11 +61,6 @@ struct dev_dax { struct range range; };
-static inline u64 range_len(struct range *range) -{ - return range->end - range->start + 1; -} - static inline struct dev_dax *to_dev_dax(struct device *dev) { return container_of(dev, struct dev_dax, dev); diff --git a/drivers/dax/device.c b/drivers/dax/device.c index 5496331f6eb6..fffc54ce0911 100644 --- a/drivers/dax/device.c +++ b/drivers/dax/device.c @@ -416,8 +416,7 @@ int dev_dax_probe(struct dev_dax *dev_dax) pgmap = devm_kzalloc(dev, sizeof(*pgmap), GFP_KERNEL); if (!pgmap) return -ENOMEM; - pgmap->res.start = range->start; - pgmap->res.end = range->end; + pgmap->range = *range; } pgmap->type = MEMORY_DEVICE_DEVDAX; addr = devm_memremap_pages(dev, pgmap); diff --git a/drivers/dax/hmem/hmem.c b/drivers/dax/hmem/hmem.c index aa260009dfc7..1a3347bb6143 100644 --- a/drivers/dax/hmem/hmem.c +++ b/drivers/dax/hmem/hmem.c @@ -13,13 +13,16 @@ static int dax_hmem_probe(struct platform_device *pdev) struct dev_dax_data data; struct dev_dax *dev_dax; struct resource *res; + struct range range;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) return -ENOMEM;
mri = dev->platform_data; - dax_region = alloc_dax_region(dev, pdev->id, res, mri->target_node, + range.start = res->start; + range.end = res->end; + dax_region = alloc_dax_region(dev, pdev->id, &range, mri->target_node, PMD_SIZE, 0); if (!dax_region) return -ENOMEM; diff --git a/drivers/dax/pmem/core.c b/drivers/dax/pmem/core.c index 4fe700884338..62b26bfceab1 100644 --- a/drivers/dax/pmem/core.c +++ b/drivers/dax/pmem/core.c @@ -9,7 +9,7 @@
struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys) { - struct resource res; + struct range range; int rc, id, region_id; resource_size_t offset; struct nd_pfn_sb *pfn_sb; @@ -50,10 +50,10 @@ struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys) if (rc != 2) return ERR_PTR(-EINVAL);
- /* adjust the dax_region resource to the start of data */ - memcpy(&res, &pgmap.res, sizeof(res)); - res.start += offset; - dax_region = alloc_dax_region(dev, region_id, &res, + /* adjust the dax_region range to the start of data */ + range = pgmap.range; + range.start += offset, + dax_region = alloc_dax_region(dev, region_id, &range, nd_region->target_node, le32_to_cpu(pfn_sb->align), IORESOURCE_DAX_STATIC); if (!dax_region) @@ -64,7 +64,7 @@ struct dev_dax *__dax_pmem_probe(struct device *dev, enum dev_dax_subsys subsys) .id = id, .pgmap = &pgmap, .subsys = subsys, - .size = resource_size(&res), + .size = range_len(&range), }; dev_dax = devm_create_dev_dax(&data);
diff --git a/drivers/gpu/drm/nouveau/nouveau_dmem.c b/drivers/gpu/drm/nouveau/nouveau_dmem.c index 4e8112fde3e6..25811ed7e274 100644 --- a/drivers/gpu/drm/nouveau/nouveau_dmem.c +++ b/drivers/gpu/drm/nouveau/nouveau_dmem.c @@ -101,7 +101,7 @@ unsigned long nouveau_dmem_page_addr(struct page *page) { struct nouveau_dmem_chunk *chunk = nouveau_page_to_chunk(page); unsigned long off = (page_to_pfn(page) << PAGE_SHIFT) - - chunk->pagemap.res.start; + chunk->pagemap.range.start;
return chunk->bo->offset + off; } @@ -249,7 +249,8 @@ nouveau_dmem_chunk_alloc(struct nouveau_drm *drm, struct page **ppage)
chunk->drm = drm; chunk->pagemap.type = MEMORY_DEVICE_PRIVATE; - chunk->pagemap.res = *res; + chunk->pagemap.range.start = res->start; + chunk->pagemap.range.end = res->end; chunk->pagemap.ops = &nouveau_dmem_pagemap_ops; chunk->pagemap.owner = drm->dev;
@@ -273,7 +274,7 @@ nouveau_dmem_chunk_alloc(struct nouveau_drm *drm, struct page **ppage) list_add(&chunk->list, &drm->dmem->chunks); mutex_unlock(&drm->dmem->mutex);
- pfn_first = chunk->pagemap.res.start >> PAGE_SHIFT; + pfn_first = chunk->pagemap.range.start >> PAGE_SHIFT; page = pfn_to_page(pfn_first); spin_lock(&drm->dmem->lock); for (i = 0; i < DMEM_CHUNK_NPAGES - 1; ++i, ++page) { @@ -294,8 +295,7 @@ nouveau_dmem_chunk_alloc(struct nouveau_drm *drm, struct page **ppage) out_bo_free: nouveau_bo_ref(NULL, &chunk->bo); out_release: - release_mem_region(chunk->pagemap.res.start, - resource_size(&chunk->pagemap.res)); + release_mem_region(chunk->pagemap.range.start, range_len(&chunk->pagemap.range)); out_free: kfree(chunk); out: @@ -382,8 +382,8 @@ nouveau_dmem_fini(struct nouveau_drm *drm) nouveau_bo_ref(NULL, &chunk->bo); list_del(&chunk->list); memunmap_pages(&chunk->pagemap); - release_mem_region(chunk->pagemap.res.start, - resource_size(&chunk->pagemap.res)); + release_mem_region(chunk->pagemap.range.start, + range_len(&chunk->pagemap.range)); kfree(chunk); }
diff --git a/drivers/nvdimm/badrange.c b/drivers/nvdimm/badrange.c index b9eeefa27e3a..aaf6e215a8c6 100644 --- a/drivers/nvdimm/badrange.c +++ b/drivers/nvdimm/badrange.c @@ -211,7 +211,7 @@ static void __add_badblock_range(struct badblocks *bb, u64 ns_offset, u64 len) }
static void badblocks_populate(struct badrange *badrange, - struct badblocks *bb, const struct resource *res) + struct badblocks *bb, const struct range *range) { struct badrange_entry *bre;
@@ -222,34 +222,34 @@ static void badblocks_populate(struct badrange *badrange, u64 bre_end = bre->start + bre->length - 1;
/* Discard intervals with no intersection */ - if (bre_end < res->start) + if (bre_end < range->start) continue; - if (bre->start > res->end) + if (bre->start > range->end) continue; /* Deal with any overlap after start of the namespace */ - if (bre->start >= res->start) { + if (bre->start >= range->start) { u64 start = bre->start; u64 len;
- if (bre_end <= res->end) + if (bre_end <= range->end) len = bre->length; else - len = res->start + resource_size(res) + len = range->start + range_len(range) - bre->start; - __add_badblock_range(bb, start - res->start, len); + __add_badblock_range(bb, start - range->start, len); continue; } /* * Deal with overlap for badrange starting before * the namespace. */ - if (bre->start < res->start) { + if (bre->start < range->start) { u64 len;
- if (bre_end < res->end) - len = bre->start + bre->length - res->start; + if (bre_end < range->end) + len = bre->start + bre->length - range->start; else - len = resource_size(res); + len = range_len(range); __add_badblock_range(bb, 0, len); } } @@ -267,7 +267,7 @@ static void badblocks_populate(struct badrange *badrange, * and add badblocks entries for all matching sub-ranges */ void nvdimm_badblocks_populate(struct nd_region *nd_region, - struct badblocks *bb, const struct resource *res) + struct badblocks *bb, const struct range *range) { struct nvdimm_bus *nvdimm_bus;
@@ -279,7 +279,7 @@ void nvdimm_badblocks_populate(struct nd_region *nd_region, nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
nvdimm_bus_lock(&nvdimm_bus->dev); - badblocks_populate(&nvdimm_bus->badrange, bb, res); + badblocks_populate(&nvdimm_bus->badrange, bb, range); nvdimm_bus_unlock(&nvdimm_bus->dev); } EXPORT_SYMBOL_GPL(nvdimm_badblocks_populate); diff --git a/drivers/nvdimm/claim.c b/drivers/nvdimm/claim.c index 45964acba944..290267e1ff9f 100644 --- a/drivers/nvdimm/claim.c +++ b/drivers/nvdimm/claim.c @@ -303,13 +303,16 @@ static int nsio_rw_bytes(struct nd_namespace_common *ndns, int devm_nsio_enable(struct device *dev, struct nd_namespace_io *nsio, resource_size_t size) { - struct resource *res = &nsio->res; struct nd_namespace_common *ndns = &nsio->common; + struct range range = { + .start = nsio->res.start, + .end = nsio->res.end, + };
nsio->size = size; - if (!devm_request_mem_region(dev, res->start, size, + if (!devm_request_mem_region(dev, range.start, size, dev_name(&ndns->dev))) { - dev_warn(dev, "could not reserve region %pR\n", res); + dev_warn(dev, "could not reserve region %pR\n", &nsio->res); return -EBUSY; }
@@ -317,9 +320,9 @@ int devm_nsio_enable(struct device *dev, struct nd_namespace_io *nsio, if (devm_init_badblocks(dev, &nsio->bb)) return -ENOMEM; nvdimm_badblocks_populate(to_nd_region(ndns->dev.parent), &nsio->bb, - &nsio->res); + &range);
- nsio->addr = devm_memremap(dev, res->start, size, ARCH_MEMREMAP_PMEM); + nsio->addr = devm_memremap(dev, range.start, size, ARCH_MEMREMAP_PMEM);
return PTR_ERR_OR_ZERO(nsio->addr); } diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h index 85c1ae813ea3..bac90afa4604 100644 --- a/drivers/nvdimm/nd.h +++ b/drivers/nvdimm/nd.h @@ -377,8 +377,9 @@ int nvdimm_namespace_detach_btt(struct nd_btt *nd_btt); const char *nvdimm_namespace_disk_name(struct nd_namespace_common *ndns, char *name); unsigned int pmem_sector_size(struct nd_namespace_common *ndns); +struct range; void nvdimm_badblocks_populate(struct nd_region *nd_region, - struct badblocks *bb, const struct resource *res); + struct badblocks *bb, const struct range *range); int devm_namespace_enable(struct device *dev, struct nd_namespace_common *ndns, resource_size_t size); void devm_namespace_disable(struct device *dev, diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c index 3e11ef8d3f5b..3c4787b92a6a 100644 --- a/drivers/nvdimm/pfn_devs.c +++ b/drivers/nvdimm/pfn_devs.c @@ -672,7 +672,7 @@ static unsigned long init_altmap_reserve(resource_size_t base)
static int __nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap) { - struct resource *res = &pgmap->res; + struct range *range = &pgmap->range; struct vmem_altmap *altmap = &pgmap->altmap; struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb; u64 offset = le64_to_cpu(pfn_sb->dataoff); @@ -689,16 +689,16 @@ static int __nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap) .end_pfn = PHYS_PFN(end), };
- memcpy(res, &nsio->res, sizeof(*res)); - res->start += start_pad; - res->end -= end_trunc; - + *range = (struct range) { + .start = nsio->res.start + start_pad, + .end = nsio->res.end - end_trunc, + }; if (nd_pfn->mode == PFN_MODE_RAM) { if (offset < reserve) return -EINVAL; nd_pfn->npfns = le64_to_cpu(pfn_sb->npfns); } else if (nd_pfn->mode == PFN_MODE_PMEM) { - nd_pfn->npfns = PHYS_PFN((resource_size(res) - offset)); + nd_pfn->npfns = PHYS_PFN((range_len(range) - offset)); if (le64_to_cpu(nd_pfn->pfn_sb->npfns) > nd_pfn->npfns) dev_info(&nd_pfn->dev, "number of pfns truncated from %lld to %ld\n", diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index fab29b514372..69cc0e783709 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -376,7 +376,7 @@ static int pmem_attach_disk(struct device *dev, struct nd_region *nd_region = to_nd_region(dev->parent); int nid = dev_to_node(dev), fua; struct resource *res = &nsio->res; - struct resource bb_res; + struct range bb_range; struct nd_pfn *nd_pfn = NULL; struct dax_device *dax_dev; struct nd_pfn_sb *pfn_sb; @@ -435,24 +435,26 @@ static int pmem_attach_disk(struct device *dev, pfn_sb = nd_pfn->pfn_sb; pmem->data_offset = le64_to_cpu(pfn_sb->dataoff); pmem->pfn_pad = resource_size(res) - - resource_size(&pmem->pgmap.res); + range_len(&pmem->pgmap.range); pmem->pfn_flags |= PFN_MAP; - memcpy(&bb_res, &pmem->pgmap.res, sizeof(bb_res)); - bb_res.start += pmem->data_offset; + bb_range = pmem->pgmap.range; + bb_range.start += pmem->data_offset; } else if (pmem_should_map_pages(dev)) { - memcpy(&pmem->pgmap.res, &nsio->res, sizeof(pmem->pgmap.res)); + pmem->pgmap.range.start = res->start; + pmem->pgmap.range.end = res->end; pmem->pgmap.type = MEMORY_DEVICE_FS_DAX; pmem->pgmap.ops = &fsdax_pagemap_ops; addr = devm_memremap_pages(dev, &pmem->pgmap); pmem->pfn_flags |= PFN_MAP; - memcpy(&bb_res, &pmem->pgmap.res, sizeof(bb_res)); + bb_range = pmem->pgmap.range; } else { if (devm_add_action_or_reset(dev, pmem_release_queue, &pmem->pgmap)) return -ENOMEM; addr = devm_memremap(dev, pmem->phys_addr, pmem->size, ARCH_MEMREMAP_PMEM); - memcpy(&bb_res, &nsio->res, sizeof(bb_res)); + bb_range.start = res->start; + bb_range.end = res->end; }
if (IS_ERR(addr)) @@ -482,7 +484,7 @@ static int pmem_attach_disk(struct device *dev, / 512); if (devm_init_badblocks(dev, &pmem->bb)) return -ENOMEM; - nvdimm_badblocks_populate(nd_region, &pmem->bb, &bb_res); + nvdimm_badblocks_populate(nd_region, &pmem->bb, &bb_range); disk->bb = &pmem->bb;
if (is_nvdimm_sync(nd_region)) @@ -593,8 +595,8 @@ static void nd_pmem_notify(struct device *dev, enum nvdimm_event event) resource_size_t offset = 0, end_trunc = 0; struct nd_namespace_common *ndns; struct nd_namespace_io *nsio; - struct resource res; struct badblocks *bb; + struct range range; struct kernfs_node *bb_state;
if (event != NVDIMM_REVALIDATE_POISON) @@ -630,9 +632,9 @@ static void nd_pmem_notify(struct device *dev, enum nvdimm_event event) nsio = to_nd_namespace_io(&ndns->dev); }
- res.start = nsio->res.start + offset; - res.end = nsio->res.end - end_trunc; - nvdimm_badblocks_populate(nd_region, bb, &res); + range.start = nsio->res.start + offset; + range.end = nsio->res.end - end_trunc; + nvdimm_badblocks_populate(nd_region, bb, &range); if (bb_state) sysfs_notify_dirent(bb_state); } diff --git a/drivers/nvdimm/region.c b/drivers/nvdimm/region.c index 0f6978e72e7c..bfce87ed72ab 100644 --- a/drivers/nvdimm/region.c +++ b/drivers/nvdimm/region.c @@ -35,7 +35,10 @@ static int nd_region_probe(struct device *dev) return rc;
if (is_memory(&nd_region->dev)) { - struct resource ndr_res; + struct range range = { + .start = nd_region->ndr_start, + .end = nd_region->ndr_start + nd_region->ndr_size - 1, + };
if (devm_init_badblocks(dev, &nd_region->bb)) return -ENODEV; @@ -44,9 +47,7 @@ static int nd_region_probe(struct device *dev) if (!nd_region->bb_state) dev_warn(&nd_region->dev, "'badblocks' notification disabled\n"); - ndr_res.start = nd_region->ndr_start; - ndr_res.end = nd_region->ndr_start + nd_region->ndr_size - 1; - nvdimm_badblocks_populate(nd_region, &nd_region->bb, &ndr_res); + nvdimm_badblocks_populate(nd_region, &nd_region->bb, &range); }
rc = nd_region_register_namespaces(nd_region, &err); @@ -121,14 +122,16 @@ static void nd_region_notify(struct device *dev, enum nvdimm_event event) { if (event == NVDIMM_REVALIDATE_POISON) { struct nd_region *nd_region = to_nd_region(dev); - struct resource res;
if (is_memory(&nd_region->dev)) { - res.start = nd_region->ndr_start; - res.end = nd_region->ndr_start + - nd_region->ndr_size - 1; + struct range range = { + .start = nd_region->ndr_start, + .end = nd_region->ndr_start + + nd_region->ndr_size - 1, + }; + nvdimm_badblocks_populate(nd_region, - &nd_region->bb, &res); + &nd_region->bb, &range); if (nd_region->bb_state) sysfs_notify_dirent(nd_region->bb_state); } diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c index f29a48f8fa59..dd6b0d51a50c 100644 --- a/drivers/pci/p2pdma.c +++ b/drivers/pci/p2pdma.c @@ -185,9 +185,8 @@ int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size, return -ENOMEM;
pgmap = &p2p_pgmap->pgmap; - pgmap->res.start = pci_resource_start(pdev, bar) + offset; - pgmap->res.end = pgmap->res.start + size - 1; - pgmap->res.flags = pci_resource_flags(pdev, bar); + pgmap->range.start = pci_resource_start(pdev, bar) + offset; + pgmap->range.end = pgmap->range.start + size - 1; pgmap->type = MEMORY_DEVICE_PCI_P2PDMA;
p2p_pgmap->provider = pdev; @@ -202,13 +201,13 @@ int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size,
error = gen_pool_add_owner(pdev->p2pdma->pool, (unsigned long)addr, pci_bus_address(pdev, bar) + offset, - resource_size(&pgmap->res), dev_to_node(&pdev->dev), + range_len(&pgmap->range), dev_to_node(&pdev->dev), pgmap->ref); if (error) goto pages_free;
- pci_info(pdev, "added peer-to-peer DMA memory %pR\n", - &pgmap->res); + pci_info(pdev, "added peer-to-peer DMA memory %#llx-%#llx\n", + pgmap->range.start, pgmap->range.end);
return 0;
diff --git a/include/linux/memremap.h b/include/linux/memremap.h index fac75e5a723b..6c21951bdb16 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -1,6 +1,7 @@ /* SPDX-License-Identifier: GPL-2.0 */ #ifndef _LINUX_MEMREMAP_H_ #define _LINUX_MEMREMAP_H_ +#include <linux/range.h> #include <linux/ioport.h> #include <linux/percpu-refcount.h>
@@ -94,7 +95,7 @@ struct dev_pagemap_ops { /** * struct dev_pagemap - metadata for ZONE_DEVICE mappings * @altmap: pre-allocated/reserved memory for vmemmap allocations - * @res: physical address range covered by @ref + * @range: physical address range covered by @ref * @ref: reference count that pins the devm_memremap_pages() mapping * @internal_ref: internal reference if @ref is not provided by the caller * @done: completion for @internal_ref @@ -107,7 +108,7 @@ struct dev_pagemap_ops { */ struct dev_pagemap { struct vmem_altmap altmap; - struct resource res; + struct range range; struct percpu_ref *ref; struct percpu_ref internal_ref; struct completion done; diff --git a/include/linux/range.h b/include/linux/range.h index d1fbeb664012..274681cc3154 100644 --- a/include/linux/range.h +++ b/include/linux/range.h @@ -1,12 +1,18 @@ /* SPDX-License-Identifier: GPL-2.0 */ #ifndef _LINUX_RANGE_H #define _LINUX_RANGE_H +#include <linux/types.h>
struct range { u64 start; u64 end; };
+static inline u64 range_len(const struct range *range) +{ + return range->end - range->start + 1; +} + int add_range(struct range *range, int az, int nr_range, u64 start, u64 end);
diff --git a/lib/test_hmm.c b/lib/test_hmm.c index e7dc3de355b7..5b4521991621 100644 --- a/lib/test_hmm.c +++ b/lib/test_hmm.c @@ -487,7 +487,8 @@ static bool dmirror_allocate_chunk(struct dmirror_device *mdevice, goto err_release;
devmem->pagemap.type = MEMORY_DEVICE_PRIVATE; - devmem->pagemap.res = *res; + devmem->pagemap.range.start = res->start; + devmem->pagemap.range.end = res->end; devmem->pagemap.ops = &dmirror_devmem_ops; devmem->pagemap.owner = mdevice;
@@ -496,9 +497,8 @@ static bool dmirror_allocate_chunk(struct dmirror_device *mdevice, goto err_free;
devmem->mdevice = mdevice; - pfn_first = devmem->pagemap.res.start >> PAGE_SHIFT; - pfn_last = pfn_first + - (resource_size(&devmem->pagemap.res) >> PAGE_SHIFT); + pfn_first = devmem->pagemap.range.start >> PAGE_SHIFT; + pfn_last = pfn_first + (range_len(&devmem->pagemap.range) >> PAGE_SHIFT); mdevice->devmem_chunks[mdevice->devmem_count++] = devmem;
mutex_unlock(&mdevice->devmem_lock); @@ -528,7 +528,7 @@ static bool dmirror_allocate_chunk(struct dmirror_device *mdevice, err_free: kfree(devmem); err_release: - release_mem_region(res->start, resource_size(res)); + release_mem_region(devmem->pagemap.range.start, range_len(&devmem->pagemap.range)); err: mutex_unlock(&mdevice->devmem_lock); return false; @@ -1100,8 +1100,8 @@ static void dmirror_device_remove(struct dmirror_device *mdevice) mdevice->devmem_chunks[i];
memunmap_pages(&devmem->pagemap); - release_mem_region(devmem->pagemap.res.start, - resource_size(&devmem->pagemap.res)); + release_mem_region(devmem->pagemap.range.start, + range_len(&devmem->pagemap.range)); kfree(devmem); } kfree(mdevice->devmem_chunks); diff --git a/mm/memremap.c b/mm/memremap.c index 8afcc54c8928..9979891fec78 100644 --- a/mm/memremap.c +++ b/mm/memremap.c @@ -70,24 +70,24 @@ static void devmap_managed_enable_put(void) } #endif /* CONFIG_DEV_PAGEMAP_OPS */
-static void pgmap_array_delete(struct resource *res) +static void pgmap_array_delete(struct range *range) { - xa_store_range(&pgmap_array, PHYS_PFN(res->start), PHYS_PFN(res->end), + xa_store_range(&pgmap_array, PHYS_PFN(range->start), PHYS_PFN(range->end), NULL, GFP_KERNEL); synchronize_rcu(); }
static unsigned long pfn_first(struct dev_pagemap *pgmap) { - return PHYS_PFN(pgmap->res.start) + + return PHYS_PFN(pgmap->range.start) + vmem_altmap_offset(pgmap_altmap(pgmap)); }
static unsigned long pfn_end(struct dev_pagemap *pgmap) { - const struct resource *res = &pgmap->res; + const struct range *range = &pgmap->range;
- return (res->start + resource_size(res)) >> PAGE_SHIFT; + return (range->start + range_len(range)) >> PAGE_SHIFT; }
static unsigned long pfn_next(unsigned long pfn) @@ -146,7 +146,7 @@ static void dev_pagemap_cleanup(struct dev_pagemap *pgmap)
void memunmap_pages(struct dev_pagemap *pgmap) { - struct resource *res = &pgmap->res; + struct range *range = &pgmap->range; struct page *first_page; unsigned long pfn; int nid; @@ -163,20 +163,20 @@ void memunmap_pages(struct dev_pagemap *pgmap) nid = page_to_nid(first_page);
mem_hotplug_begin(); - remove_pfn_range_from_zone(page_zone(first_page), PHYS_PFN(res->start), - PHYS_PFN(resource_size(res))); + remove_pfn_range_from_zone(page_zone(first_page), PHYS_PFN(range->start), + PHYS_PFN(range_len(range))); if (pgmap->type == MEMORY_DEVICE_PRIVATE) { - __remove_pages(PHYS_PFN(res->start), - PHYS_PFN(resource_size(res)), NULL); + __remove_pages(PHYS_PFN(range->start), + PHYS_PFN(range_len(range)), NULL); } else { - arch_remove_memory(nid, res->start, resource_size(res), + arch_remove_memory(nid, range->start, range_len(range), pgmap_altmap(pgmap)); - kasan_remove_zero_shadow(__va(res->start), resource_size(res)); + kasan_remove_zero_shadow(__va(range->start), range_len(range)); } mem_hotplug_done();
- untrack_pfn(NULL, PHYS_PFN(res->start), resource_size(res)); - pgmap_array_delete(res); + untrack_pfn(NULL, PHYS_PFN(range->start), range_len(range)); + pgmap_array_delete(range); WARN_ONCE(pgmap->altmap.alloc, "failed to free all reserved pages\n"); devmap_managed_enable_put(); } @@ -202,7 +202,7 @@ static void dev_pagemap_percpu_release(struct percpu_ref *ref) */ void *memremap_pages(struct dev_pagemap *pgmap, int nid) { - struct resource *res = &pgmap->res; + struct range *range = &pgmap->range; struct dev_pagemap *conflict_pgmap; struct mhp_params params = { /* @@ -271,7 +271,7 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid) return ERR_PTR(error); }
- conflict_pgmap = get_dev_pagemap(PHYS_PFN(res->start), NULL); + conflict_pgmap = get_dev_pagemap(PHYS_PFN(range->start), NULL); if (conflict_pgmap) { WARN(1, "Conflicting mapping in same section\n"); put_dev_pagemap(conflict_pgmap); @@ -279,7 +279,7 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid) goto err_array; }
- conflict_pgmap = get_dev_pagemap(PHYS_PFN(res->end), NULL); + conflict_pgmap = get_dev_pagemap(PHYS_PFN(range->end), NULL); if (conflict_pgmap) { WARN(1, "Conflicting mapping in same section\n"); put_dev_pagemap(conflict_pgmap); @@ -287,26 +287,27 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid) goto err_array; }
- is_ram = region_intersects(res->start, resource_size(res), + is_ram = region_intersects(range->start, range_len(range), IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE);
if (is_ram != REGION_DISJOINT) { - WARN_ONCE(1, "%s attempted on %s region %pr\n", __func__, - is_ram == REGION_MIXED ? "mixed" : "ram", res); + WARN_ONCE(1, "attempted on %s region %#llx-%#llx\n", + is_ram == REGION_MIXED ? "mixed" : "ram", + range->start, range->end); error = -ENXIO; goto err_array; }
- error = xa_err(xa_store_range(&pgmap_array, PHYS_PFN(res->start), - PHYS_PFN(res->end), pgmap, GFP_KERNEL)); + error = xa_err(xa_store_range(&pgmap_array, PHYS_PFN(range->start), + PHYS_PFN(range->end), pgmap, GFP_KERNEL)); if (error) goto err_array;
if (nid < 0) nid = numa_mem_id();
- error = track_pfn_remap(NULL, ¶ms.pgprot, PHYS_PFN(res->start), - 0, resource_size(res)); + error = track_pfn_remap(NULL, ¶ms.pgprot, PHYS_PFN(range->start), 0, + range_len(range)); if (error) goto err_pfn_remap;
@@ -324,16 +325,16 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid) * arch_add_memory(). */ if (pgmap->type == MEMORY_DEVICE_PRIVATE) { - error = add_pages(nid, PHYS_PFN(res->start), - PHYS_PFN(resource_size(res)), ¶ms); + error = add_pages(nid, PHYS_PFN(range->start), + PHYS_PFN(range_len(range)), ¶ms); } else { - error = kasan_add_zero_shadow(__va(res->start), resource_size(res)); + error = kasan_add_zero_shadow(__va(range->start), range_len(range)); if (error) { mem_hotplug_done(); goto err_kasan; }
- error = arch_add_memory(nid, res->start, resource_size(res), + error = arch_add_memory(nid, range->start, range_len(range), ¶ms); }
@@ -341,8 +342,8 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid) struct zone *zone;
zone = &NODE_DATA(nid)->node_zones[ZONE_DEVICE]; - move_pfn_range_to_zone(zone, PHYS_PFN(res->start), - PHYS_PFN(resource_size(res)), params.altmap); + move_pfn_range_to_zone(zone, PHYS_PFN(range->start), + PHYS_PFN(range_len(range)), params.altmap); }
mem_hotplug_done(); @@ -354,17 +355,17 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid) * to allow us to do the work while not holding the hotplug lock. */ memmap_init_zone_device(&NODE_DATA(nid)->node_zones[ZONE_DEVICE], - PHYS_PFN(res->start), - PHYS_PFN(resource_size(res)), pgmap); + PHYS_PFN(range->start), + PHYS_PFN(range_len(range)), pgmap); percpu_ref_get_many(pgmap->ref, pfn_end(pgmap) - pfn_first(pgmap)); - return __va(res->start); + return __va(range->start);
err_add_memory: - kasan_remove_zero_shadow(__va(res->start), resource_size(res)); + kasan_remove_zero_shadow(__va(range->start), range_len(range)); err_kasan: - untrack_pfn(NULL, PHYS_PFN(res->start), resource_size(res)); + untrack_pfn(NULL, PHYS_PFN(range->start), range_len(range)); err_pfn_remap: - pgmap_array_delete(res); + pgmap_array_delete(range); err_array: dev_pagemap_kill(pgmap); dev_pagemap_cleanup(pgmap); @@ -389,7 +390,7 @@ EXPORT_SYMBOL_GPL(memremap_pages); * 'live' on entry and will be killed and reaped at * devm_memremap_pages_release() time, or if this routine fails. * - * 4/ res is expected to be a host memory range that could feasibly be + * 4/ range is expected to be a host memory range that could feasibly be * treated as a "System RAM" range, i.e. not a device mmio range, but * this is not enforced. */ @@ -446,7 +447,7 @@ struct dev_pagemap *get_dev_pagemap(unsigned long pfn, * In the cached case we're already holding a live reference. */ if (pgmap) { - if (phys >= pgmap->res.start && phys <= pgmap->res.end) + if (phys >= pgmap->range.start && phys <= pgmap->range.end) return pgmap; put_dev_pagemap(pgmap); } diff --git a/tools/testing/nvdimm/test/iomap.c b/tools/testing/nvdimm/test/iomap.c index 03e40b3b0106..c62d372d426f 100644 --- a/tools/testing/nvdimm/test/iomap.c +++ b/tools/testing/nvdimm/test/iomap.c @@ -126,7 +126,7 @@ static void dev_pagemap_percpu_release(struct percpu_ref *ref) void *__wrap_devm_memremap_pages(struct device *dev, struct dev_pagemap *pgmap) { int error; - resource_size_t offset = pgmap->res.start; + resource_size_t offset = pgmap->range.start; struct nfit_test_resource *nfit_res = get_nfit_res(offset);
if (!nfit_res)
In support of device-dax growing the ability to front physically dis-contiguous ranges of memory, update devm_memremap_pages() to track multiple ranges with a single reference counter and devm instance.
Cc: Paul Mackerras paulus@ozlabs.org Cc: Michael Ellerman mpe@ellerman.id.au Cc: Benjamin Herrenschmidt benh@kernel.crashing.org Cc: Dan Williams dan.j.williams@intel.com Cc: Vishal Verma vishal.l.verma@intel.com Cc: Dave Jiang dave.jiang@intel.com Cc: Ben Skeggs bskeggs@redhat.com Cc: David Airlie airlied@linux.ie Cc: Daniel Vetter daniel@ffwll.ch Cc: Ira Weiny ira.weiny@intel.com Cc: Jason Gunthorpe jgg@mellanox.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- arch/powerpc/kvm/book3s_hv_uvmem.c | 1 drivers/dax/device.c | 1 drivers/gpu/drm/nouveau/nouveau_dmem.c | 1 drivers/nvdimm/pfn_devs.c | 1 drivers/nvdimm/pmem.c | 1 drivers/pci/p2pdma.c | 1 include/linux/memremap.h | 10 + lib/test_hmm.c | 1 mm/memremap.c | 258 +++++++++++++++++++------------- 9 files changed, 165 insertions(+), 110 deletions(-)
diff --git a/arch/powerpc/kvm/book3s_hv_uvmem.c b/arch/powerpc/kvm/book3s_hv_uvmem.c index 29ec555055c2..84e5a2dc8be5 100644 --- a/arch/powerpc/kvm/book3s_hv_uvmem.c +++ b/arch/powerpc/kvm/book3s_hv_uvmem.c @@ -1172,6 +1172,7 @@ int kvmppc_uvmem_init(void) kvmppc_uvmem_pgmap.type = MEMORY_DEVICE_PRIVATE; kvmppc_uvmem_pgmap.range.start = res->start; kvmppc_uvmem_pgmap.range.end = res->end; + kvmppc_uvmem_pgmap.nr_range = 1; kvmppc_uvmem_pgmap.ops = &kvmppc_uvmem_ops; /* just one global instance: */ kvmppc_uvmem_pgmap.owner = &kvmppc_uvmem_pgmap; diff --git a/drivers/dax/device.c b/drivers/dax/device.c index fffc54ce0911..f3755df4ae29 100644 --- a/drivers/dax/device.c +++ b/drivers/dax/device.c @@ -417,6 +417,7 @@ int dev_dax_probe(struct dev_dax *dev_dax) if (!pgmap) return -ENOMEM; pgmap->range = *range; + pgmap->nr_range = 1; } pgmap->type = MEMORY_DEVICE_DEVDAX; addr = devm_memremap_pages(dev, pgmap); diff --git a/drivers/gpu/drm/nouveau/nouveau_dmem.c b/drivers/gpu/drm/nouveau/nouveau_dmem.c index 25811ed7e274..a13c6215bba8 100644 --- a/drivers/gpu/drm/nouveau/nouveau_dmem.c +++ b/drivers/gpu/drm/nouveau/nouveau_dmem.c @@ -251,6 +251,7 @@ nouveau_dmem_chunk_alloc(struct nouveau_drm *drm, struct page **ppage) chunk->pagemap.type = MEMORY_DEVICE_PRIVATE; chunk->pagemap.range.start = res->start; chunk->pagemap.range.end = res->end; + chunk->pagemap.nr_range = 1; chunk->pagemap.ops = &nouveau_dmem_pagemap_ops; chunk->pagemap.owner = drm->dev;
diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c index 3c4787b92a6a..b499df630d4d 100644 --- a/drivers/nvdimm/pfn_devs.c +++ b/drivers/nvdimm/pfn_devs.c @@ -693,6 +693,7 @@ static int __nvdimm_setup_pfn(struct nd_pfn *nd_pfn, struct dev_pagemap *pgmap) .start = nsio->res.start + start_pad, .end = nsio->res.end - end_trunc, }; + pgmap->nr_range = 1; if (nd_pfn->mode == PFN_MODE_RAM) { if (offset < reserve) return -EINVAL; diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 69cc0e783709..1f45af363a94 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -442,6 +442,7 @@ static int pmem_attach_disk(struct device *dev, } else if (pmem_should_map_pages(dev)) { pmem->pgmap.range.start = res->start; pmem->pgmap.range.end = res->end; + pmem->pgmap.nr_range = 1; pmem->pgmap.type = MEMORY_DEVICE_FS_DAX; pmem->pgmap.ops = &fsdax_pagemap_ops; addr = devm_memremap_pages(dev, &pmem->pgmap); diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c index dd6b0d51a50c..403304785561 100644 --- a/drivers/pci/p2pdma.c +++ b/drivers/pci/p2pdma.c @@ -187,6 +187,7 @@ int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size, pgmap = &p2p_pgmap->pgmap; pgmap->range.start = pci_resource_start(pdev, bar) + offset; pgmap->range.end = pgmap->range.start + size - 1; + pgmap->nr_range = 1; pgmap->type = MEMORY_DEVICE_PCI_P2PDMA;
p2p_pgmap->provider = pdev; diff --git a/include/linux/memremap.h b/include/linux/memremap.h index 6c21951bdb16..4e9c738f4b31 100644 --- a/include/linux/memremap.h +++ b/include/linux/memremap.h @@ -95,7 +95,6 @@ struct dev_pagemap_ops { /** * struct dev_pagemap - metadata for ZONE_DEVICE mappings * @altmap: pre-allocated/reserved memory for vmemmap allocations - * @range: physical address range covered by @ref * @ref: reference count that pins the devm_memremap_pages() mapping * @internal_ref: internal reference if @ref is not provided by the caller * @done: completion for @internal_ref @@ -105,10 +104,12 @@ struct dev_pagemap_ops { * @owner: an opaque pointer identifying the entity that manages this * instance. Used by various helpers to make sure that no * foreign ZONE_DEVICE memory is accessed. + * @nr_range: number of ranges to be mapped + * @range: range to be mapped when nr_range == 1 + * @ranges: array of ranges to be mapped when nr_range > 1 */ struct dev_pagemap { struct vmem_altmap altmap; - struct range range; struct percpu_ref *ref; struct percpu_ref internal_ref; struct completion done; @@ -116,6 +117,11 @@ struct dev_pagemap { unsigned int flags; const struct dev_pagemap_ops *ops; void *owner; + int nr_range; + union { + struct range range; + struct range ranges[0]; + }; };
static inline struct vmem_altmap *pgmap_altmap(struct dev_pagemap *pgmap) diff --git a/lib/test_hmm.c b/lib/test_hmm.c index 5b4521991621..e3065d6123f0 100644 --- a/lib/test_hmm.c +++ b/lib/test_hmm.c @@ -489,6 +489,7 @@ static bool dmirror_allocate_chunk(struct dmirror_device *mdevice, devmem->pagemap.type = MEMORY_DEVICE_PRIVATE; devmem->pagemap.range.start = res->start; devmem->pagemap.range.end = res->end; + devmem->pagemap.nr_range = 1; devmem->pagemap.ops = &dmirror_devmem_ops; devmem->pagemap.owner = mdevice;
diff --git a/mm/memremap.c b/mm/memremap.c index 9979891fec78..a7346638a09f 100644 --- a/mm/memremap.c +++ b/mm/memremap.c @@ -77,15 +77,19 @@ static void pgmap_array_delete(struct range *range) synchronize_rcu(); }
-static unsigned long pfn_first(struct dev_pagemap *pgmap) +static unsigned long pfn_first(struct dev_pagemap *pgmap, int range_id) { - return PHYS_PFN(pgmap->range.start) + - vmem_altmap_offset(pgmap_altmap(pgmap)); + struct range *range = &pgmap->ranges[range_id]; + unsigned long pfn = PHYS_PFN(range->start); + + if (range_id) + return pfn; + return pfn + vmem_altmap_offset(pgmap_altmap(pgmap)); }
-static unsigned long pfn_end(struct dev_pagemap *pgmap) +static unsigned long pfn_end(struct dev_pagemap *pgmap, int range_id) { - const struct range *range = &pgmap->range; + const struct range *range = &pgmap->ranges[range_id];
return (range->start + range_len(range)) >> PAGE_SHIFT; } @@ -117,8 +121,8 @@ bool pfn_zone_device_reserved(unsigned long pfn) return ret; }
-#define for_each_device_pfn(pfn, map) \ - for (pfn = pfn_first(map); pfn < pfn_end(map); pfn = pfn_next(pfn)) +#define for_each_device_pfn(pfn, map, i) \ + for (pfn = pfn_first(map, i); pfn < pfn_end(map, i); pfn = pfn_next(pfn))
static void dev_pagemap_kill(struct dev_pagemap *pgmap) { @@ -144,20 +148,14 @@ static void dev_pagemap_cleanup(struct dev_pagemap *pgmap) pgmap->ref = NULL; }
-void memunmap_pages(struct dev_pagemap *pgmap) +static void pageunmap_range(struct dev_pagemap *pgmap, int range_id) { - struct range *range = &pgmap->range; + struct range *range = &pgmap->ranges[range_id]; struct page *first_page; - unsigned long pfn; int nid;
- dev_pagemap_kill(pgmap); - for_each_device_pfn(pfn, pgmap) - put_page(pfn_to_page(pfn)); - dev_pagemap_cleanup(pgmap); - /* make sure to access a memmap that was actually initialized */ - first_page = pfn_to_page(pfn_first(pgmap)); + first_page = pfn_to_page(pfn_first(pgmap, range_id));
/* pages are dead and unused, undo the arch mapping */ nid = page_to_nid(first_page); @@ -177,6 +175,22 @@ void memunmap_pages(struct dev_pagemap *pgmap)
untrack_pfn(NULL, PHYS_PFN(range->start), range_len(range)); pgmap_array_delete(range); +} + +void memunmap_pages(struct dev_pagemap *pgmap) +{ + unsigned long pfn; + int i; + + dev_pagemap_kill(pgmap); + for (i = 0; i < pgmap->nr_range; i++) + for_each_device_pfn(pfn, pgmap, i) + put_page(pfn_to_page(pfn)); + dev_pagemap_cleanup(pgmap); + + for (i = 0; i < pgmap->nr_range; i++) + pageunmap_range(pgmap, i); + WARN_ONCE(pgmap->altmap.alloc, "failed to free all reserved pages\n"); devmap_managed_enable_put(); } @@ -195,96 +209,29 @@ static void dev_pagemap_percpu_release(struct percpu_ref *ref) complete(&pgmap->done); }
-/* - * Not device managed version of dev_memremap_pages, undone by - * memunmap_pages(). Please use dev_memremap_pages if you have a struct - * device available. - */ -void *memremap_pages(struct dev_pagemap *pgmap, int nid) +static int pagemap_range(struct dev_pagemap *pgmap, struct mhp_params *params, + int range_id, int nid) { - struct range *range = &pgmap->range; + struct range *range = &pgmap->ranges[range_id]; struct dev_pagemap *conflict_pgmap; - struct mhp_params params = { - /* - * We do not want any optional features only our own memmap - */ - .altmap = pgmap_altmap(pgmap), - .pgprot = PAGE_KERNEL, - }; int error, is_ram; - bool need_devmap_managed = true;
- switch (pgmap->type) { - case MEMORY_DEVICE_PRIVATE: - if (!IS_ENABLED(CONFIG_DEVICE_PRIVATE)) { - WARN(1, "Device private memory not supported\n"); - return ERR_PTR(-EINVAL); - } - if (!pgmap->ops || !pgmap->ops->migrate_to_ram) { - WARN(1, "Missing migrate_to_ram method\n"); - return ERR_PTR(-EINVAL); - } - if (!pgmap->owner) { - WARN(1, "Missing owner\n"); - return ERR_PTR(-EINVAL); - } - break; - case MEMORY_DEVICE_FS_DAX: - if (!IS_ENABLED(CONFIG_ZONE_DEVICE) || - IS_ENABLED(CONFIG_FS_DAX_LIMITED)) { - WARN(1, "File system DAX not supported\n"); - return ERR_PTR(-EINVAL); - } - break; - case MEMORY_DEVICE_DEVDAX: - need_devmap_managed = false; - break; - case MEMORY_DEVICE_PCI_P2PDMA: - params.pgprot = pgprot_noncached(params.pgprot); - need_devmap_managed = false; - break; - default: - WARN(1, "Invalid pgmap type %d\n", pgmap->type); - break; - } - - if (!pgmap->ref) { - if (pgmap->ops && (pgmap->ops->kill || pgmap->ops->cleanup)) - return ERR_PTR(-EINVAL); - - init_completion(&pgmap->done); - error = percpu_ref_init(&pgmap->internal_ref, - dev_pagemap_percpu_release, 0, GFP_KERNEL); - if (error) - return ERR_PTR(error); - pgmap->ref = &pgmap->internal_ref; - } else { - if (!pgmap->ops || !pgmap->ops->kill || !pgmap->ops->cleanup) { - WARN(1, "Missing reference count teardown definition\n"); - return ERR_PTR(-EINVAL); - } - } - - if (need_devmap_managed) { - error = devmap_managed_enable_get(pgmap); - if (error) - return ERR_PTR(error); - } + if (WARN_ONCE(pgmap_altmap(pgmap) && range_id > 0, + "altmap not supported for multiple ranges\n")) + return -EINVAL;
conflict_pgmap = get_dev_pagemap(PHYS_PFN(range->start), NULL); if (conflict_pgmap) { WARN(1, "Conflicting mapping in same section\n"); put_dev_pagemap(conflict_pgmap); - error = -ENOMEM; - goto err_array; + return -ENOMEM; }
conflict_pgmap = get_dev_pagemap(PHYS_PFN(range->end), NULL); if (conflict_pgmap) { WARN(1, "Conflicting mapping in same section\n"); put_dev_pagemap(conflict_pgmap); - error = -ENOMEM; - goto err_array; + return -ENOMEM; }
is_ram = region_intersects(range->start, range_len(range), @@ -294,19 +241,18 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid) WARN_ONCE(1, "attempted on %s region %#llx-%#llx\n", is_ram == REGION_MIXED ? "mixed" : "ram", range->start, range->end); - error = -ENXIO; - goto err_array; + return -ENXIO; }
error = xa_err(xa_store_range(&pgmap_array, PHYS_PFN(range->start), PHYS_PFN(range->end), pgmap, GFP_KERNEL)); if (error) - goto err_array; + return error;
if (nid < 0) nid = numa_mem_id();
- error = track_pfn_remap(NULL, ¶ms.pgprot, PHYS_PFN(range->start), 0, + error = track_pfn_remap(NULL, ¶ms->pgprot, PHYS_PFN(range->start), 0, range_len(range)); if (error) goto err_pfn_remap; @@ -326,7 +272,7 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid) */ if (pgmap->type == MEMORY_DEVICE_PRIVATE) { error = add_pages(nid, PHYS_PFN(range->start), - PHYS_PFN(range_len(range)), ¶ms); + PHYS_PFN(range_len(range)), params); } else { error = kasan_add_zero_shadow(__va(range->start), range_len(range)); if (error) { @@ -335,7 +281,7 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid) }
error = arch_add_memory(nid, range->start, range_len(range), - ¶ms); + params); }
if (!error) { @@ -343,7 +289,7 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid)
zone = &NODE_DATA(nid)->node_zones[ZONE_DEVICE]; move_pfn_range_to_zone(zone, PHYS_PFN(range->start), - PHYS_PFN(range_len(range)), params.altmap); + PHYS_PFN(range_len(range)), params->altmap); }
mem_hotplug_done(); @@ -357,20 +303,116 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid) memmap_init_zone_device(&NODE_DATA(nid)->node_zones[ZONE_DEVICE], PHYS_PFN(range->start), PHYS_PFN(range_len(range)), pgmap); - percpu_ref_get_many(pgmap->ref, pfn_end(pgmap) - pfn_first(pgmap)); - return __va(range->start); + percpu_ref_get_many(pgmap->ref, pfn_end(pgmap, range_id) + - pfn_first(pgmap, range_id)); + return 0;
- err_add_memory: +err_add_memory: kasan_remove_zero_shadow(__va(range->start), range_len(range)); - err_kasan: +err_kasan: untrack_pfn(NULL, PHYS_PFN(range->start), range_len(range)); - err_pfn_remap: +err_pfn_remap: pgmap_array_delete(range); - err_array: - dev_pagemap_kill(pgmap); - dev_pagemap_cleanup(pgmap); - devmap_managed_enable_put(); - return ERR_PTR(error); + return error; +} + + +/* + * Not device managed version of dev_memremap_pages, undone by + * memunmap_pages(). Please use dev_memremap_pages if you have a struct + * device available. + */ +void *memremap_pages(struct dev_pagemap *pgmap, int nid) +{ + struct mhp_params params = { + .altmap = pgmap_altmap(pgmap), + .pgprot = PAGE_KERNEL, + }; + const int nr_range = pgmap->nr_range; + bool need_devmap_managed = true; + int error, i; + + if (WARN_ONCE(!nr_range, "nr_range must be specified\n")) + return ERR_PTR(-EINVAL); + + switch (pgmap->type) { + case MEMORY_DEVICE_PRIVATE: + if (!IS_ENABLED(CONFIG_DEVICE_PRIVATE)) { + WARN(1, "Device private memory not supported\n"); + return ERR_PTR(-EINVAL); + } + if (!pgmap->ops || !pgmap->ops->migrate_to_ram) { + WARN(1, "Missing migrate_to_ram method\n"); + return ERR_PTR(-EINVAL); + } + if (!pgmap->owner) { + WARN(1, "Missing owner\n"); + return ERR_PTR(-EINVAL); + } + break; + case MEMORY_DEVICE_FS_DAX: + if (!IS_ENABLED(CONFIG_ZONE_DEVICE) || + IS_ENABLED(CONFIG_FS_DAX_LIMITED)) { + WARN(1, "File system DAX not supported\n"); + return ERR_PTR(-EINVAL); + } + break; + case MEMORY_DEVICE_DEVDAX: + need_devmap_managed = false; + break; + case MEMORY_DEVICE_PCI_P2PDMA: + params.pgprot = pgprot_noncached(params.pgprot); + need_devmap_managed = false; + break; + default: + WARN(1, "Invalid pgmap type %d\n", pgmap->type); + break; + } + + if (!pgmap->ref) { + if (pgmap->ops && (pgmap->ops->kill || pgmap->ops->cleanup)) + return ERR_PTR(-EINVAL); + + init_completion(&pgmap->done); + error = percpu_ref_init(&pgmap->internal_ref, + dev_pagemap_percpu_release, 0, GFP_KERNEL); + if (error) + return ERR_PTR(error); + pgmap->ref = &pgmap->internal_ref; + } else { + if (!pgmap->ops || !pgmap->ops->kill || !pgmap->ops->cleanup) { + WARN(1, "Missing reference count teardown definition\n"); + return ERR_PTR(-EINVAL); + } + } + + if (need_devmap_managed) { + error = devmap_managed_enable_get(pgmap); + if (error) + return ERR_PTR(error); + } + + /* + * Clear the pgmap nr_range as it will be incremented for each + * successfully processed range. This communicates how many + * regions to unwind in the abort case. + */ + pgmap->nr_range = 0; + error = 0; + for (i = 0; i < nr_range; i++) { + error = pagemap_range(pgmap, ¶ms, i, nid); + if (error) + break; + pgmap->nr_range++; + } + + if (i < nr_range) { + memunmap_pages(pgmap); + pgmap->nr_range = nr_range; + return ERR_PTR(error); + } + + return __va(pgmap->ranges[0].start); } EXPORT_SYMBOL_GPL(memremap_pages);
Break the requirement that device-dax instances are physically contiguous. With this constraint removed it allows fragmented available capacity to be fully allocated.
This capability is useful to mitigate the "noisy neighbor" problem with memory-side-cache management for virtual machines, or any other scenario where a platform address boundary also designates a performance boundary. For example a direct mapped memory side cache might rotate cache colors at 1GB boundaries. With dis-contiguous allocations a device-dax instance could be configured to contain only 1 cache color.
It also satisfies Joao's use case (see link) for partitioning memory for exclusive guest access. It allows for a future potential mode where the host kernel need not allocate 'struct page' capacity up-front.
Link: https://lore.kernel.org/lkml/20200110190313.17144-1-joao.m.martins@oracle.co... Reported-by: Joao Martins joao.m.martins@oracle.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- drivers/dax/bus.c | 230 +++++++++++++++++++++++++++++++--------- drivers/dax/dax-private.h | 9 +- drivers/dax/device.c | 55 ++++++---- drivers/dax/kmem.c | 132 +++++++++++++++-------- tools/testing/nvdimm/dax-dev.c | 20 ++- 5 files changed, 319 insertions(+), 127 deletions(-)
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index 00fa73a8dfb4..f342e36c69a1 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -136,15 +136,27 @@ static bool is_static(struct dax_region *dax_region) return (dax_region->res.flags & IORESOURCE_DAX_STATIC) != 0; }
+static u64 dev_dax_size(struct dev_dax *dev_dax) +{ + u64 size = 0; + int i; + + device_lock_assert(&dev_dax->dev); + + for (i = 0; i < dev_dax->nr_range; i++) + size += range_len(&dev_dax->ranges[i].range); + + return size; +} + static int dax_bus_probe(struct device *dev) { struct dax_device_driver *dax_drv = to_dax_drv(dev->driver); struct dev_dax *dev_dax = to_dev_dax(dev); struct dax_region *dax_region = dev_dax->region; - struct range *range = &dev_dax->range; int rc;
- if (range_len(range) == 0 || dev_dax->id < 0) + if (dev_dax_size(dev_dax) == 0 || dev_dax->id < 0) return -ENXIO;
rc = dax_drv->probe(dev_dax); @@ -354,15 +366,19 @@ void kill_dev_dax(struct dev_dax *dev_dax) } EXPORT_SYMBOL_GPL(kill_dev_dax);
-static void free_dev_dax_range(struct dev_dax *dev_dax) +static void free_dev_dax_ranges(struct dev_dax *dev_dax) { struct dax_region *dax_region = dev_dax->region; - struct range *range = &dev_dax->range; + int i;
device_lock_assert(dax_region->dev); - if (range_len(range)) + for (i = 0; i < dev_dax->nr_range; i++) { + struct range *range = &dev_dax->ranges[i].range; + __release_region(&dax_region->res, range->start, range_len(range)); + } + dev_dax->nr_range = 0; }
static void unregister_dev_dax(void *dev) @@ -372,7 +388,7 @@ static void unregister_dev_dax(void *dev) dev_dbg(dev, "%s\n", __func__);
kill_dev_dax(dev_dax); - free_dev_dax_range(dev_dax); + free_dev_dax_ranges(dev_dax); device_del(dev); put_device(dev); } @@ -423,7 +439,7 @@ static ssize_t delete_store(struct device *dev, struct device_attribute *attr, device_lock(dev); device_lock(victim); dev_dax = to_dev_dax(victim); - if (victim->driver || range_len(&dev_dax->range)) + if (victim->driver || dev_dax_size(dev_dax)) rc = -EBUSY; else { /* @@ -569,51 +585,83 @@ static int alloc_dev_dax_range(struct dev_dax *dev_dax, u64 start, struct dax_region *dax_region = dev_dax->region; struct resource *res = &dax_region->res; struct device *dev = &dev_dax->dev; + struct dev_dax_range *ranges; + unsigned long pgoff = 0; struct resource *alloc; + int i;
device_lock_assert(dax_region->dev);
/* handle the seed alloc special case */ if (!size) { - dev_dax->range = (struct range) { - .start = res->start, - .end = res->start - 1, - }; + if (dev_WARN_ONCE(dev, dev_dax->nr_range, + "0-size allocation must be first\n")) + return -EBUSY; + /* nr_range == 0 is elsewhere special cased as 0-size device */ return 0; }
+ ranges = krealloc(dev_dax->ranges, sizeof(*ranges) + * (dev_dax->nr_range + 1), GFP_KERNEL); + if (!ranges) + return -ENOMEM; + alloc = __request_region(res, start, size, dev_name(dev), 0); - if (!alloc) + if (!alloc && !dev_dax->nr_range) { + /* + * If we adjusted an existing @ranges leave it alone, + * but if this was an empty set of ranges nothing else + * will release @ranges, so do it now. + */ + kfree(ranges); return -ENOMEM; + }
- dev_dax->range = (struct range) { - .start = alloc->start, - .end = alloc->end, + for (i = 0; i < dev_dax->nr_range; i++) + pgoff += PHYS_PFN(range_len(&ranges[i].range)); + dev_dax->ranges = ranges; + ranges[dev_dax->nr_range++] = (struct dev_dax_range) { + .pgoff = pgoff, + .range = { + .start = alloc->start, + .end = alloc->end, + }, };
+ dev_dbg(dev, "alloc range[%d]: %pa:%pa\n", dev_dax->nr_range - 1, + &alloc->start, &alloc->end); + return 0; }
static int adjust_dev_dax_range(struct dev_dax *dev_dax, struct resource *res, resource_size_t size) { + int last_range = dev_dax->nr_range - 1; + struct dev_dax_range *dax_range = &dev_dax->ranges[last_range]; struct dax_region *dax_region = dev_dax->region; - struct range *range = &dev_dax->range; - int rc = 0; + bool is_shrink = resource_size(res) > size; + struct range *range = &dax_range->range; + struct device *dev = &dev_dax->dev; + int rc;
device_lock_assert(dax_region->dev);
- if (size) - rc = adjust_resource(res, range->start, size); - else - __release_region(&dax_region->res, range->start, range_len(range)); + if (dev_WARN_ONCE(dev, !size, "deletion is handled by dev_dax_shrink\n")) + return -EINVAL; + + rc = adjust_resource(res, range->start, size); if (rc) return rc;
- dev_dax->range = (struct range) { + *range = (struct range) { .start = range->start, .end = range->start + size - 1, };
+ dev_dbg(dev, "%s range[%d]: %#llx:%#llx\n", is_shrink ? "shrink" : "extend", + last_range, (unsigned long long) range->start, + (unsigned long long) range->end); + return 0; }
@@ -621,7 +669,11 @@ static ssize_t size_show(struct device *dev, struct device_attribute *attr, char *buf) { struct dev_dax *dev_dax = to_dev_dax(dev); - unsigned long long size = range_len(&dev_dax->range); + unsigned long long size; + + device_lock(dev); + size = dev_dax_size(dev_dax); + device_unlock(dev);
return sprintf(buf, "%llu\n", size); } @@ -639,32 +691,82 @@ static bool alloc_is_aligned(struct dax_region *dax_region,
static int dev_dax_shrink(struct dev_dax *dev_dax, resource_size_t size) { + resource_size_t to_shrink = dev_dax_size(dev_dax) - size; struct dax_region *dax_region = dev_dax->region; - struct range *range = &dev_dax->range; - struct resource *res, *adjust = NULL; struct device *dev = &dev_dax->dev; - - for_each_dax_region_resource(dax_region, res) - if (strcmp(res->name, dev_name(dev)) == 0 - && res->start == range->start) { - adjust = res; - break; + int i; + + for (i = dev_dax->nr_range - 1; i >= 0; i--) { + struct range *range = &dev_dax->ranges[i].range; + struct resource *adjust = NULL, *res; + resource_size_t shrink; + + shrink = min(to_shrink, range_len(range)); + if (shrink >= range_len(range)) { + __release_region(&dax_region->res, range->start, + range_len(range)); + dev_dax->nr_range--; + dev_dbg(dev, "delete range[%d]: %#llx:%#llx\n", i, + (unsigned long long) range->start, + (unsigned long long) range->end); + to_shrink -= shrink; + if (!to_shrink) + break; + continue; }
- if (dev_WARN_ONCE(dev, !adjust, "failed to find matching resource\n")) - return -ENXIO; - return adjust_dev_dax_range(dev_dax, adjust, size); + for_each_dax_region_resource(dax_region, res) + if (strcmp(res->name, dev_name(dev)) == 0 + && res->start == range->start) { + adjust = res; + break; + } + + if (dev_WARN_ONCE(dev, !adjust || i != dev_dax->nr_range - 1, + "failed to find matching resource\n")) + return -ENXIO; + return adjust_dev_dax_range(dev_dax, adjust, range_len(range) + - shrink); + } + return 0; +} + +/* + * Only allow adjustments that preserve the relative pgoff of existing + * allocations. I.e. the dev_dax->ranges array is ordered by increasing pgoff. + */ +static bool adjust_ok(struct dev_dax *dev_dax, struct resource *res) +{ + struct dev_dax_range *last; + int i; + + if (dev_dax->nr_range == 0) + return false; + if (strcmp(res->name, dev_name(&dev_dax->dev)) != 0) + return false; + last = &dev_dax->ranges[dev_dax->nr_range - 1]; + if (last->range.start != res->start || last->range.end != res->end) + return false; + for (i = 0; i < dev_dax->nr_range - 1; i++) { + struct dev_dax_range *dax_range = &dev_dax->ranges[i]; + + if (dax_range->pgoff > last->pgoff) + return false; + } + + return true; }
static ssize_t dev_dax_resize(struct dax_region *dax_region, struct dev_dax *dev_dax, resource_size_t size) { resource_size_t avail = dax_region_avail_size(dax_region), to_alloc; - resource_size_t dev_size = range_len(&dev_dax->range); + resource_size_t dev_size = dev_dax_size(dev_dax); struct resource *region_res = &dax_region->res; struct device *dev = &dev_dax->dev; - const char *name = dev_name(dev); struct resource *res, *first; + resource_size_t alloc = 0; + int rc;
if (dev->driver) return -EBUSY; @@ -685,35 +787,47 @@ static ssize_t dev_dax_resize(struct dax_region *dax_region, * may involve adjusting the end of an existing resource, or * allocating a new resource. */ +retry: first = region_res->child; if (!first) return alloc_dev_dax_range(dev_dax, dax_region->res.start, to_alloc); - for (res = first; to_alloc && res; res = res->sibling) { + + rc = -ENOSPC; + for (res = first; res; res = res->sibling) { struct resource *next = res->sibling; - resource_size_t free;
/* space at the beginning of the region */ - free = 0; - if (res == first && res->start > dax_region->res.start) - free = res->start - dax_region->res.start; - if (free >= to_alloc && dev_size == 0) - return alloc_dev_dax_range(dev_dax, dax_region->res.start, to_alloc); + if (res == first && res->start > dax_region->res.start) { + alloc = min(res->start - dax_region->res.start, to_alloc); + rc = alloc_dev_dax_range(dev_dax, dax_region->res.start, alloc); + break; + }
- free = 0; + alloc = 0; /* space between allocations */ if (next && next->start > res->end + 1) - free = next->start - res->end + 1; + alloc = min(next->start - (res->end + 1), to_alloc);
/* space at the end of the region */ - if (free < to_alloc && !next && res->end < region_res->end) - free = region_res->end - res->end; + if (!alloc && !next && res->end < region_res->end) + alloc = min(region_res->end - res->end, to_alloc);
- if (free >= to_alloc && strcmp(name, res->name) == 0) - return adjust_dev_dax_range(dev_dax, res, resource_size(res) + to_alloc); - else if (free >= to_alloc && dev_size == 0) - return alloc_dev_dax_range(dev_dax, res->end + 1, to_alloc); + if (!alloc) + continue; + + if (adjust_ok(dev_dax, res)) { + rc = adjust_dev_dax_range(dev_dax, res, resource_size(res) + alloc); + break; + } + rc = alloc_dev_dax_range(dev_dax, res->end + 1, alloc); + break; } - return -ENOSPC; + if (rc) + return rc; + to_alloc -= alloc; + if (to_alloc) + goto retry; + return 0; }
static ssize_t size_store(struct device *dev, struct device_attribute *attr, @@ -767,8 +881,15 @@ static ssize_t resource_show(struct device *dev, struct device_attribute *attr, char *buf) { struct dev_dax *dev_dax = to_dev_dax(dev); + struct dax_region *dax_region = dev_dax->region; + unsigned long long start; + + if (dev_dax->nr_range < 1) + start = dax_region->res.start; + else + start = dev_dax->ranges[0].range.start;
- return sprintf(buf, "%#llx\n", dev_dax->range.start); + return sprintf(buf, "%#llx\n", start); } static DEVICE_ATTR(resource, 0400, resource_show, NULL);
@@ -833,6 +954,7 @@ static void dev_dax_release(struct device *dev) put_dax(dax_dev); free_dev_dax_id(dev_dax); dax_region_put(dax_region); + kfree(dev_dax->ranges); kfree(dev_dax->pgmap); kfree(dev_dax); } @@ -941,7 +1063,7 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) err_alloc_dax: kfree(dev_dax->pgmap); err_pgmap: - free_dev_dax_range(dev_dax); + free_dev_dax_ranges(dev_dax); err_range: free_dev_dax_id(dev_dax); err_id: diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h index 0cbb2ec81ca7..f863287107fd 100644 --- a/drivers/dax/dax-private.h +++ b/drivers/dax/dax-private.h @@ -49,7 +49,8 @@ struct dax_region { * @id: ida allocated id * @dev - device core * @pgmap - pgmap for memmap setup / lifetime (driver owned) - * @range: resource range for the instance + * @nr_range: size of @ranges + * @ranges: resource-span + pgoff tuples for the instance */ struct dev_dax { struct dax_region *region; @@ -58,7 +59,11 @@ struct dev_dax { int id; struct device dev; struct dev_pagemap *pgmap; - struct range range; + int nr_range; + struct dev_dax_range { + unsigned long pgoff; + struct range range; + } *ranges; };
static inline struct dev_dax *to_dev_dax(struct device *dev) diff --git a/drivers/dax/device.c b/drivers/dax/device.c index f3755df4ae29..2bfc5c83e3b0 100644 --- a/drivers/dax/device.c +++ b/drivers/dax/device.c @@ -55,15 +55,22 @@ static int check_vma(struct dev_dax *dev_dax, struct vm_area_struct *vma, __weak phys_addr_t dax_pgoff_to_phys(struct dev_dax *dev_dax, pgoff_t pgoff, unsigned long size) { - struct range *range = &dev_dax->range; - phys_addr_t phys; - - phys = pgoff * PAGE_SIZE + range->start; - if (phys >= range->start && phys <= range->end) { + int i; + + for (i = 0; i < dev_dax->nr_range; i++) { + struct dev_dax_range *dax_range = &dev_dax->ranges[i]; + struct range *range = &dax_range->range; + unsigned long long pgoff_end; + phys_addr_t phys; + + pgoff_end = dax_range->pgoff + PHYS_PFN(range_len(range)) - 1; + if (pgoff < dax_range->pgoff || pgoff > pgoff_end) + continue; + phys = PFN_PHYS(pgoff - dax_range->pgoff) + range->start; if (phys + size - 1 <= range->end) return phys; + break; } - return -1; }
@@ -395,30 +402,40 @@ static void dev_dax_kill(void *dev_dax) int dev_dax_probe(struct dev_dax *dev_dax) { struct dax_device *dax_dev = dev_dax->dax_dev; - struct range *range = &dev_dax->range; struct device *dev = &dev_dax->dev; struct dev_pagemap *pgmap; struct inode *inode; struct cdev *cdev; void *addr; - int rc; - - /* 1:1 map region resource range to device-dax instance range */ - if (!devm_request_mem_region(dev, range->start, range_len(range), - dev_name(dev))) { - dev_warn(dev, "could not reserve range: %#llx - %#llx\n", - range->start, range->end); - return -EBUSY; - } + int rc, i;
pgmap = dev_dax->pgmap; + if (dev_WARN_ONCE(dev, pgmap && dev_dax->nr_range > 1, + "static pgmap / multi-range device conflict\n")) + return -EINVAL; + if (!pgmap) { - pgmap = devm_kzalloc(dev, sizeof(*pgmap), GFP_KERNEL); + pgmap = devm_kzalloc(dev, sizeof(*pgmap) + sizeof(struct range) + * (dev_dax->nr_range - 1), GFP_KERNEL); if (!pgmap) return -ENOMEM; - pgmap->range = *range; - pgmap->nr_range = 1; + pgmap->nr_range = dev_dax->nr_range; + } + + for (i = 0; i < dev_dax->nr_range; i++) { + struct range *range = &dev_dax->ranges[i].range; + + if (!devm_request_mem_region(dev, range->start, + range_len(range), dev_name(dev))) { + dev_warn(dev, "mapping%d: %#llx-%#llx could not reserve range\n", + i, range->start, range->end); + return -EBUSY; + } + /* don't update the range for static pgmap */ + if (!dev_dax->pgmap) + pgmap->ranges[i] = *range; } + pgmap->type = MEMORY_DEVICE_DEVDAX; addr = devm_memremap_pages(dev, pgmap); if (IS_ERR(addr)) diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c index b1be8a53b26a..7dcb2902e9b1 100644 --- a/drivers/dax/kmem.c +++ b/drivers/dax/kmem.c @@ -19,25 +19,28 @@ static const char *kmem_name; /* Set if any memory will remain added when the driver will be unloaded. */ static bool any_hotremove_failed;
-static struct range dax_kmem_range(struct dev_dax *dev_dax) +static int dax_kmem_range(struct dev_dax *dev_dax, int i, struct range *r) { - struct range range; + struct dev_dax_range *dax_range = &dev_dax->ranges[i]; + struct range *range = &dax_range->range;
/* memory-block align the hotplug range */ - range.start = ALIGN(dev_dax->range.start, memory_block_size_bytes()); - range.end = ALIGN_DOWN(dev_dax->range.end + 1, - memory_block_size_bytes()) - 1; - return range; + r->start = ALIGN(range->start, memory_block_size_bytes()); + r->end = ALIGN_DOWN(range->end + 1, memory_block_size_bytes()) - 1; + if (r->start >= r->end) { + r->start = range->start; + r->end = range->end; + return -ENOSPC; + } + return 0; }
int dev_dax_kmem_probe(struct dev_dax *dev_dax) { - struct range range = dax_kmem_range(dev_dax); int numa_node = dev_dax->target_node; struct device *dev = &dev_dax->dev; - struct resource *res; + int i, mapped = 0; char *res_name; - int rc;
/* * Ensure good NUMA information for the persistent memory. @@ -55,32 +58,56 @@ int dev_dax_kmem_probe(struct dev_dax *dev_dax) if (!res_name) return -ENOMEM;
- res = request_mem_region(range.start, range_len(&range), res_name); - if (!res) { - dev_warn(dev, "could not reserve region [%#llx-%#llx]\n", - range.start, range.end); - kfree(res_name); - return -EBUSY; - } - - /* - * Temporarily clear busy to allow add_memory_driver_managed() - * to claim it. - */ - res->flags &= ~IORESOURCE_BUSY; - - /* - * Ensure that future kexec'd kernels will not treat this as RAM - * automatically. - */ - rc = add_memory_driver_managed(numa_node, res->start, - resource_size(res), kmem_name); - - res->flags |= IORESOURCE_BUSY; - if (rc) { - release_mem_region(range.start, range_len(&range)); - kfree(res_name); - return rc; + for (i = 0; i < dev_dax->nr_range; i++) { + struct resource *res; + struct range range; + int rc; + + rc = dax_kmem_range(dev_dax, i, &range); + if (rc) { + dev_info(dev, "mapping%d: %#llx-%#llx too small after alignment\n", + i, range.start, range.end); + continue; + } + + res = request_mem_region(range.start, range_len(&range), res_name); + if (!res) { + dev_warn(dev, "mapping%d: %#llx-%#llx could not reserve region\n", + i, range.start, range.end); + /* + * Once some memory has been onlined we can't + * assume that it can be un-onlined safely. + */ + if (mapped) + continue; + kfree(res_name); + return -EBUSY; + } + + /* + * Temporarily clear busy to allow + * add_memory_driver_managed() to claim it. + */ + res->flags &= ~IORESOURCE_BUSY; + + /* + * Ensure that future kexec'd kernels will not treat + * this as RAM automatically. + */ + rc = add_memory_driver_managed(numa_node, range.start, + range_len(&range), kmem_name); + + res->flags |= IORESOURCE_BUSY; + if (rc) { + dev_warn(dev, "mapping%d: %#llx-%#llx memory add failed\n", + i, range.start, range.end); + release_mem_region(range.start, range_len(&range)); + if (mapped) + continue; + kfree(res_name); + return rc; + } + mapped++; }
dev_set_drvdata(dev, res_name); @@ -91,10 +118,9 @@ int dev_dax_kmem_probe(struct dev_dax *dev_dax) #ifdef CONFIG_MEMORY_HOTREMOVE static void dax_kmem_release(struct dev_dax *dev_dax) { - int rc; + int i, success = 0; struct device *dev = &dev_dax->dev; const char *res_name = dev_get_drvdata(dev); - struct range range = dax_kmem_range(dev_dax);
/* * We have one shot for removing memory, if some memory blocks were not @@ -102,17 +128,31 @@ static void dax_kmem_release(struct dev_dax *dev_dax) * there is no way to hotremove this memory until reboot because device * unbind will proceed regardless of the remove_memory result. */ - rc = remove_memory(dev_dax->target_node, range.start, range_len(&range)); - if (rc == 0) { - release_mem_region(range.start, range_len(&range)); - dev_set_drvdata(dev, NULL); - kfree(res_name); - return; + for (i = 0; i < dev_dax->nr_range; i++) { + struct range range; + int rc; + + rc = dax_kmem_range(dev_dax, i, &range); + if (rc) + continue; + + rc = remove_memory(dev_dax->target_node, range.start, + range_len(&range)); + if (rc == 0) { + release_mem_region(range.start, range_len(&range)); + success++; + continue; + } + any_hotremove_failed = true; + dev_err(dev, + "mapping%d: %#llx-%#llx cannot be hotremoved until the next reboot\n", + i, range.start, range.end); }
- any_hotremove_failed = true; - dev_err(dev, "%#llx-%#llx cannot be hotremoved until the next reboot\n", - range.start, range.end); + if (success >= dev_dax->nr_range) { + kfree(res_name); + dev_set_drvdata(dev, NULL); + } } #else static void dax_kmem_release(struct dev_dax *dev_dax) diff --git a/tools/testing/nvdimm/dax-dev.c b/tools/testing/nvdimm/dax-dev.c index 38d8e55c4a0d..fb342a8c98d3 100644 --- a/tools/testing/nvdimm/dax-dev.c +++ b/tools/testing/nvdimm/dax-dev.c @@ -9,11 +9,18 @@ phys_addr_t dax_pgoff_to_phys(struct dev_dax *dev_dax, pgoff_t pgoff, unsigned long size) { - struct range *range = &dev_dax->range; - phys_addr_t addr; + int i;
- addr = pgoff * PAGE_SIZE + range->start; - if (addr >= range->start && addr <= range->end) { + for (i = 0; i < dev_dax->nr_range; i++) { + struct dev_dax_range *dax_range = &dev_dax->ranges[i]; + struct range *range = &dax_range->range; + unsigned long long pgoff_end; + phys_addr_t addr; + + pgoff_end = dax_range->pgoff + PHYS_PFN(range_len(range)) - 1; + if (pgoff < dax_range->pgoff || pgoff > pgoff_end) + continue; + addr = PFN_PHYS(pgoff - dax_range->pgoff) + range->start; if (addr + size - 1 <= range->end) { if (get_nfit_res(addr)) { struct page *page; @@ -23,9 +30,10 @@ phys_addr_t dax_pgoff_to_phys(struct dev_dax *dev_dax, pgoff_t pgoff,
page = vmalloc_to_page((void *)addr); return PFN_PHYS(page_to_pfn(page)); - } else - return addr; + } + return addr; } + break; } return -1; }
In support of interrogating the physical address layout of a device with dis-contiguous ranges, introduce a sysfs directory with 'start', 'end', and 'page_offset' attributes. The alternative is trying to parse /proc/iomem, and that file will not reflect the extent layout until the device is enabled.
Cc: Vishal Verma vishal.l.verma@intel.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- drivers/dax/bus.c | 191 +++++++++++++++++++++++++++++++++++++++++++++ drivers/dax/dax-private.h | 14 +++ 2 files changed, 203 insertions(+), 2 deletions(-)
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index f342e36c69a1..ffb27964deb2 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -579,6 +579,167 @@ struct dax_region *alloc_dax_region(struct device *parent, int region_id, } EXPORT_SYMBOL_GPL(alloc_dax_region);
+static void dax_mapping_release(struct device *dev) +{ + struct dax_mapping *mapping = to_dax_mapping(dev); + struct dev_dax *dev_dax = to_dev_dax(dev->parent); + + ida_free(&dev_dax->ida, mapping->id); + kfree(mapping); +} + +static void unregister_dax_mapping(void *data) +{ + struct device *dev = data; + struct dax_mapping *mapping = to_dax_mapping(dev); + struct dev_dax *dev_dax = to_dev_dax(dev->parent); + struct dax_region *dax_region = dev_dax->region; + + dev_dbg(dev, "%s\n", __func__); + + device_lock_assert(dax_region->dev); + + dev_dax->ranges[mapping->range_id].mapping = NULL; + mapping->range_id = -1; + + device_del(dev); + put_device(dev); +} + +static struct dev_dax_range *get_dax_range(struct device *dev) +{ + struct dax_mapping *mapping = to_dax_mapping(dev); + struct dev_dax *dev_dax = to_dev_dax(dev->parent); + struct dax_region *dax_region = dev_dax->region; + + device_lock(dax_region->dev); + if (mapping->range_id < 0) { + device_unlock(dax_region->dev); + return NULL; + } + + return &dev_dax->ranges[mapping->range_id]; +} + +static void put_dax_range(struct dev_dax_range *dax_range) +{ + struct dax_mapping *mapping = dax_range->mapping; + struct dev_dax *dev_dax = to_dev_dax(mapping->dev.parent); + struct dax_region *dax_region = dev_dax->region; + + device_unlock(dax_region->dev); +} + +static ssize_t start_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct dev_dax_range *dax_range; + ssize_t rc; + + dax_range = get_dax_range(dev); + if (!dax_range) + return -ENXIO; + rc = sprintf(buf, "%#llx\n", dax_range->range.start); + put_dax_range(dax_range); + + return rc; +} +static DEVICE_ATTR(start, 0400, start_show, NULL); + +static ssize_t end_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct dev_dax_range *dax_range; + ssize_t rc; + + dax_range = get_dax_range(dev); + if (!dax_range) + return -ENXIO; + rc = sprintf(buf, "%#llx\n", dax_range->range.end); + put_dax_range(dax_range); + + return rc; +} +static DEVICE_ATTR(end, 0400, end_show, NULL); + +static ssize_t pgoff_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct dev_dax_range *dax_range; + ssize_t rc; + + dax_range = get_dax_range(dev); + if (!dax_range) + return -ENXIO; + rc = sprintf(buf, "%#lx\n", dax_range->pgoff); + put_dax_range(dax_range); + + return rc; +} +static DEVICE_ATTR(page_offset, 0400, pgoff_show, NULL); + +static struct attribute *dax_mapping_attributes[] = { + &dev_attr_start.attr, + &dev_attr_end.attr, + &dev_attr_page_offset.attr, + NULL, +}; + +static const struct attribute_group dax_mapping_attribute_group = { + .attrs = dax_mapping_attributes, +}; + +static const struct attribute_group *dax_mapping_attribute_groups[] = { + &dax_mapping_attribute_group, + NULL, +}; + +static struct device_type dax_mapping_type = { + .release = dax_mapping_release, + .groups = dax_mapping_attribute_groups, +}; + +static int devm_register_dax_mapping(struct dev_dax *dev_dax, int range_id) +{ + struct dax_region *dax_region = dev_dax->region; + struct dax_mapping *mapping; + struct device *dev; + int rc; + + device_lock_assert(dax_region->dev); + + if (dev_WARN_ONCE(&dev_dax->dev, !dax_region->dev->driver, + "region disabled\n")) + return -ENXIO; + + mapping = kzalloc(sizeof(*mapping), GFP_KERNEL); + if (!mapping) + return -ENOMEM; + mapping->range_id = range_id; + mapping->id = ida_alloc(&dev_dax->ida, GFP_KERNEL); + if (mapping->id < 0) { + kfree(mapping); + return -ENOMEM; + } + dev_dax->ranges[range_id].mapping = mapping; + dev = &mapping->dev; + device_initialize(dev); + dev->parent = &dev_dax->dev; + dev->type = &dax_mapping_type; + dev_set_name(dev, "mapping%d", mapping->id); + rc = device_add(dev); + if (rc) { + put_device(dev); + return rc; + } + + rc = devm_add_action_or_reset(dax_region->dev, unregister_dax_mapping, + dev); + if (rc) + return rc; + return 0; +} + static int alloc_dev_dax_range(struct dev_dax *dev_dax, u64 start, resource_size_t size) { @@ -588,7 +749,7 @@ static int alloc_dev_dax_range(struct dev_dax *dev_dax, u64 start, struct dev_dax_range *ranges; unsigned long pgoff = 0; struct resource *alloc; - int i; + int i, rc;
device_lock_assert(dax_region->dev);
@@ -630,6 +791,22 @@ static int alloc_dev_dax_range(struct dev_dax *dev_dax, u64 start,
dev_dbg(dev, "alloc range[%d]: %pa:%pa\n", dev_dax->nr_range - 1, &alloc->start, &alloc->end); + /* + * A dev_dax instance must be registered before mapping device + * children can be added. Defer to devm_create_dev_dax() to add + * the initial mapping device. + */ + if (!device_is_registered(&dev_dax->dev)) + return 0; + + rc = devm_register_dax_mapping(dev_dax, dev_dax->nr_range - 1); + if (rc) { + dev_dbg(dev, "delete range[%d]: %pa:%pa\n", dev_dax->nr_range - 1, + &alloc->start, &alloc->end); + dev_dax->nr_range--; + __release_region(res, alloc->start, resource_size(alloc)); + return rc; + }
return 0; } @@ -698,11 +875,14 @@ static int dev_dax_shrink(struct dev_dax *dev_dax, resource_size_t size)
for (i = dev_dax->nr_range - 1; i >= 0; i--) { struct range *range = &dev_dax->ranges[i].range; + struct dax_mapping *mapping = dev_dax->ranges[i].mapping; struct resource *adjust = NULL, *res; resource_size_t shrink;
shrink = min(to_shrink, range_len(range)); if (shrink >= range_len(range)) { + devm_release_action(dax_region->dev, + unregister_dax_mapping, &mapping->dev); __release_region(&dax_region->res, range->start, range_len(range)); dev_dax->nr_range--; @@ -1033,9 +1213,9 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) /* a device_dax instance is dead while the driver is not attached */ kill_dax(dax_dev);
- /* from here on we're committed to teardown via dev_dax_release() */ dev_dax->dax_dev = dax_dev; dev_dax->target_node = dax_region->target_node; + ida_init(&dev_dax->ida); kref_get(&dax_region->kref);
inode = dax_inode(dax_dev); @@ -1058,6 +1238,13 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data) if (rc) return ERR_PTR(rc);
+ /* register mapping device for the initial allocation range */ + if (dev_dax->nr_range && range_len(&dev_dax->ranges[0].range)) { + rc = devm_register_dax_mapping(dev_dax, 0); + if (rc) + return ERR_PTR(rc); + } + return dev_dax;
err_alloc_dax: diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h index f863287107fd..13780f62b95e 100644 --- a/drivers/dax/dax-private.h +++ b/drivers/dax/dax-private.h @@ -40,6 +40,12 @@ struct dax_region { struct device *youngest; };
+struct dax_mapping { + struct device dev; + int range_id; + int id; +}; + /** * struct dev_dax - instance data for a subdivision of a dax region, and * data while the device is activated in the driver. @@ -47,6 +53,7 @@ struct dax_region { * @dax_dev - core dax functionality * @target_node: effective numa node if dev_dax memory range is onlined * @id: ida allocated id + * @ida: mapping id allocator * @dev - device core * @pgmap - pgmap for memmap setup / lifetime (driver owned) * @nr_range: size of @ranges @@ -57,12 +64,14 @@ struct dev_dax { struct dax_device *dax_dev; int target_node; int id; + struct ida ida; struct device dev; struct dev_pagemap *pgmap; int nr_range; struct dev_dax_range { unsigned long pgoff; struct range range; + struct dax_mapping *mapping; } *ranges; };
@@ -70,4 +79,9 @@ static inline struct dev_dax *to_dev_dax(struct device *dev) { return container_of(dev, struct dev_dax, dev); } + +static inline struct dax_mapping *to_dax_mapping(struct device *dev) +{ + return container_of(dev, struct dax_mapping, dev); +} #endif
From: Joao Martins joao.m.martins@oracle.com
Introduce @align to struct dev_dax.
When creating a new device, we still initialize to the default dax_region @align. Child devices belonging to a region may wish to keep a different alignment property instead of a global region-defined one.
Signed-off-by: Joao Martins joao.m.martins@oracle.com Link: https://lore.kernel.org/r/20200716172913.19658-2-joao.m.martins@oracle.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- drivers/dax/bus.c | 1 + drivers/dax/dax-private.h | 1 + drivers/dax/device.c | 35 +++++++++++++++-------------------- 3 files changed, 17 insertions(+), 20 deletions(-)
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index ffb27964deb2..feca1413481c 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -1215,6 +1215,7 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data)
dev_dax->dax_dev = dax_dev; dev_dax->target_node = dax_region->target_node; + dev_dax->align = dax_region->align; ida_init(&dev_dax->ida); kref_get(&dax_region->kref);
diff --git a/drivers/dax/dax-private.h b/drivers/dax/dax-private.h index 13780f62b95e..96ef5a8ae0ba 100644 --- a/drivers/dax/dax-private.h +++ b/drivers/dax/dax-private.h @@ -62,6 +62,7 @@ struct dax_mapping { struct dev_dax { struct dax_region *region; struct dax_device *dax_dev; + unsigned int align; int target_node; int id; struct ida ida; diff --git a/drivers/dax/device.c b/drivers/dax/device.c index 2bfc5c83e3b0..346c7bb8cf06 100644 --- a/drivers/dax/device.c +++ b/drivers/dax/device.c @@ -17,7 +17,6 @@ static int check_vma(struct dev_dax *dev_dax, struct vm_area_struct *vma, const char *func) { - struct dax_region *dax_region = dev_dax->region; struct device *dev = &dev_dax->dev; unsigned long mask;
@@ -32,7 +31,7 @@ static int check_vma(struct dev_dax *dev_dax, struct vm_area_struct *vma, return -EINVAL; }
- mask = dax_region->align - 1; + mask = dev_dax->align - 1; if (vma->vm_start & mask || vma->vm_end & mask) { dev_info_ratelimited(dev, "%s: %s: fail, unaligned vma (%#lx - %#lx, %#lx)\n", @@ -86,13 +85,13 @@ static vm_fault_t __dev_dax_pte_fault(struct dev_dax *dev_dax, return VM_FAULT_SIGBUS;
dax_region = dev_dax->region; - if (dax_region->align > PAGE_SIZE) { + if (dev_dax->align > PAGE_SIZE) { dev_dbg(dev, "alignment (%#x) > fault size (%#x)\n", - dax_region->align, fault_size); + dev_dax->align, fault_size); return VM_FAULT_SIGBUS; }
- if (fault_size != dax_region->align) + if (fault_size != dev_dax->align) return VM_FAULT_SIGBUS;
phys = dax_pgoff_to_phys(dev_dax, vmf->pgoff, PAGE_SIZE); @@ -120,15 +119,15 @@ static vm_fault_t __dev_dax_pmd_fault(struct dev_dax *dev_dax, return VM_FAULT_SIGBUS;
dax_region = dev_dax->region; - if (dax_region->align > PMD_SIZE) { + if (dev_dax->align > PMD_SIZE) { dev_dbg(dev, "alignment (%#x) > fault size (%#x)\n", - dax_region->align, fault_size); + dev_dax->align, fault_size); return VM_FAULT_SIGBUS; }
- if (fault_size < dax_region->align) + if (fault_size < dev_dax->align) return VM_FAULT_SIGBUS; - else if (fault_size > dax_region->align) + else if (fault_size > dev_dax->align) return VM_FAULT_FALLBACK;
/* if we are outside of the VMA */ @@ -164,15 +163,15 @@ static vm_fault_t __dev_dax_pud_fault(struct dev_dax *dev_dax, return VM_FAULT_SIGBUS;
dax_region = dev_dax->region; - if (dax_region->align > PUD_SIZE) { + if (dev_dax->align > PUD_SIZE) { dev_dbg(dev, "alignment (%#x) > fault size (%#x)\n", - dax_region->align, fault_size); + dev_dax->align, fault_size); return VM_FAULT_SIGBUS; }
- if (fault_size < dax_region->align) + if (fault_size < dev_dax->align) return VM_FAULT_SIGBUS; - else if (fault_size > dax_region->align) + else if (fault_size > dev_dax->align) return VM_FAULT_FALLBACK;
/* if we are outside of the VMA */ @@ -267,9 +266,8 @@ static int dev_dax_split(struct vm_area_struct *vma, unsigned long addr) { struct file *filp = vma->vm_file; struct dev_dax *dev_dax = filp->private_data; - struct dax_region *dax_region = dev_dax->region;
- if (!IS_ALIGNED(addr, dax_region->align)) + if (!IS_ALIGNED(addr, dev_dax->align)) return -EINVAL; return 0; } @@ -278,9 +276,8 @@ static unsigned long dev_dax_pagesize(struct vm_area_struct *vma) { struct file *filp = vma->vm_file; struct dev_dax *dev_dax = filp->private_data; - struct dax_region *dax_region = dev_dax->region;
- return dax_region->align; + return dev_dax->align; }
static const struct vm_operations_struct dax_vm_ops = { @@ -319,13 +316,11 @@ static unsigned long dax_get_unmapped_area(struct file *filp, { unsigned long off, off_end, off_align, len_align, addr_align, align; struct dev_dax *dev_dax = filp ? filp->private_data : NULL; - struct dax_region *dax_region;
if (!dev_dax || addr) goto out;
- dax_region = dev_dax->region; - align = dax_region->align; + align = dev_dax->align; off = pgoff << PAGE_SHIFT; off_end = off + len; off_align = round_up(off, align);
From: Joao Martins joao.m.martins@oracle.com
Introduce a device align attribute. While doing so, rename the region align attribute to be more explicitly named as so, but keep it named as @align to retain the API for tools like daxctl.
Changes on align may not always be valid, when say certain mappings were created with 2M and then we switch to 1G. So, we validate all ranges against the new value being attempted, post resizing.
Signed-off-by: Joao Martins joao.m.martins@oracle.com Link: https://lore.kernel.org/r/20200716172913.19658-3-joao.m.martins@oracle.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- drivers/dax/bus.c | 102 ++++++++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 92 insertions(+), 10 deletions(-)
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index feca1413481c..7a9439132573 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -230,14 +230,15 @@ static ssize_t region_size_show(struct device *dev, static struct device_attribute dev_attr_region_size = __ATTR(size, 0444, region_size_show, NULL);
-static ssize_t align_show(struct device *dev, +static ssize_t region_align_show(struct device *dev, struct device_attribute *attr, char *buf) { struct dax_region *dax_region = dev_get_drvdata(dev);
return sprintf(buf, "%u\n", dax_region->align); } -static DEVICE_ATTR_RO(align); +static struct device_attribute dev_attr_region_align = + __ATTR(align, 0400, region_align_show, NULL);
#define for_each_dax_region_resource(dax_region, res) \ for (res = (dax_region)->res.child; res; res = res->sibling) @@ -488,7 +489,7 @@ static umode_t dax_region_visible(struct kobject *kobj, struct attribute *a, static struct attribute *dax_region_attributes[] = { &dev_attr_available_size.attr, &dev_attr_region_size.attr, - &dev_attr_align.attr, + &dev_attr_region_align.attr, &dev_attr_create.attr, &dev_attr_seed.attr, &dev_attr_delete.attr, @@ -855,15 +856,13 @@ static ssize_t size_show(struct device *dev, return sprintf(buf, "%llu\n", size); }
-static bool alloc_is_aligned(struct dax_region *dax_region, - resource_size_t size) +static bool alloc_is_aligned(struct dev_dax *dev_dax, resource_size_t size) { /* * The minimum mapping granularity for a device instance is a * single subsection, unless the arch says otherwise. */ - return IS_ALIGNED(size, max_t(unsigned long, dax_region->align, - memremap_compat_align())); + return IS_ALIGNED(size, max_t(unsigned long, dev_dax->align, memremap_compat_align())); }
static int dev_dax_shrink(struct dev_dax *dev_dax, resource_size_t size) @@ -958,7 +957,7 @@ static ssize_t dev_dax_resize(struct dax_region *dax_region, return dev_dax_shrink(dev_dax, size);
to_alloc = size - dev_size; - if (dev_WARN_ONCE(dev, !alloc_is_aligned(dax_region, to_alloc), + if (dev_WARN_ONCE(dev, !alloc_is_aligned(dev_dax, to_alloc), "resize of %pa misaligned\n", &to_alloc)) return -ENXIO;
@@ -1022,7 +1021,7 @@ static ssize_t size_store(struct device *dev, struct device_attribute *attr, if (rc) return rc;
- if (!alloc_is_aligned(dax_region, val)) { + if (!alloc_is_aligned(dev_dax, val)) { dev_dbg(dev, "%s: size: %lld misaligned\n", __func__, val); return -EINVAL; } @@ -1041,6 +1040,87 @@ static ssize_t size_store(struct device *dev, struct device_attribute *attr, } static DEVICE_ATTR_RW(size);
+static ssize_t align_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct dev_dax *dev_dax = to_dev_dax(dev); + + return sprintf(buf, "%d\n", dev_dax->align); +} + +static ssize_t dev_dax_validate_align(struct dev_dax *dev_dax) +{ + resource_size_t dev_size = dev_dax_size(dev_dax); + struct device *dev = &dev_dax->dev; + ssize_t rc, i; + + if (dev->driver) + return -EBUSY; + + rc = -EINVAL; + if (dev_size > 0 && !alloc_is_aligned(dev_dax, dev_size)) { + dev_dbg(dev, "%s: align %u invalid for size %llu\n", + __func__, dev_dax->align, dev_size); + return rc; + } + + for (i = 0; i < dev_dax->nr_range; i++) { + size_t len = range_len(&dev_dax->ranges[i].range); + + if (!alloc_is_aligned(dev_dax, len)) { + dev_dbg(dev, "%s: align %u invalid for range %ld\n", + __func__, dev_dax->align, i); + return rc; + } + } + + switch (dev_dax->align) { + case PUD_SIZE: + if (!IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)) + break; + fallthrough; + case PMD_SIZE: + if (!has_transparent_hugepage()) + break; + fallthrough; + case PAGE_SIZE: + rc = 0; + break; + } + + return rc; +} + +static ssize_t align_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t len) +{ + struct dev_dax *dev_dax = to_dev_dax(dev); + struct dax_region *dax_region = dev_dax->region; + unsigned long long val, align_save; + ssize_t rc; + + rc = kstrtoull(buf, 0, &val); + if (rc) + return -ENXIO; + + device_lock(dax_region->dev); + if (!dax_region->dev->driver) { + device_unlock(dax_region->dev); + return -ENXIO; + } + + device_lock(dev); + align_save = dev_dax->align; + dev_dax->align = val; + rc = dev_dax_validate_align(dev_dax); + if (rc) + dev_dax->align = align_save; + device_unlock(dev); + device_unlock(dax_region->dev); + return rc == 0 ? len : rc; +} +static DEVICE_ATTR_RW(align); + static int dev_dax_target_node(struct dev_dax *dev_dax) { struct dax_region *dax_region = dev_dax->region; @@ -1101,7 +1181,8 @@ static umode_t dev_dax_visible(struct kobject *kobj, struct attribute *a, int n) return 0; if (a == &dev_attr_numa_node.attr && !IS_ENABLED(CONFIG_NUMA)) return 0; - if (a == &dev_attr_size.attr && is_static(dax_region)) + if ((a == &dev_attr_align.attr || + a == &dev_attr_size.attr) && is_static(dax_region)) return 0444; return a->mode; } @@ -1110,6 +1191,7 @@ static struct attribute *dev_dax_attributes[] = { &dev_attr_modalias.attr, &dev_attr_size.attr, &dev_attr_target_node.attr, + &dev_attr_align.attr, &dev_attr_resource.attr, &dev_attr_numa_node.attr, NULL,
From: Joao Martins joao.m.martins@oracle.com
Introduce a new module parameter for dax_hmem which initializes all region devices as free, rather than allocating a pagemap for the region by default.
All hmem devices created with dax_hmem.region_idle=1 will have full available size for creating dynamic dax devices.
Signed-off-by: Joao Martins joao.m.martins@oracle.com Link: https://lore.kernel.org/r/20200716172913.19658-4-joao.m.martins@oracle.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- drivers/dax/hmem/hmem.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/dax/hmem/hmem.c b/drivers/dax/hmem/hmem.c index 1a3347bb6143..1bf040dbc834 100644 --- a/drivers/dax/hmem/hmem.c +++ b/drivers/dax/hmem/hmem.c @@ -5,6 +5,9 @@ #include <linux/pfn_t.h> #include "../bus.h"
+static bool region_idle; +module_param_named(region_idle, region_idle, bool, 0644); + static int dax_hmem_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; @@ -30,7 +33,7 @@ static int dax_hmem_probe(struct platform_device *pdev) data = (struct dev_dax_data) { .dax_region = dax_region, .id = -1, - .size = resource_size(res), + .size = region_idle ? 0 : resource_size(res), }; dev_dax = devm_create_dev_dax(&data); if (IS_ERR(dev_dax))
From: Joao Martins joao.m.martins@oracle.com
Add a sysfs attribute which denotes a range from the dax region to be allocated. It's an write only @mapping sysfs attribute in the format of '<start>-<end>' to allocate a range. @start and @end use hexadecimal values and the @pgoff is implicitly ordered wrt to previous writes to @mapping sysfs e.g. a write of a range of length 1G the pgoff is 0..1G(-4K), a second write will use @pgoff for 1G+4K..<size>.
This range mapping interface is useful for:
1) Application which want to implement its own allocation logic, and thus pick the desired ranges from dax_region.
2) For use cases like VMM fast restart[0] where after kexec we want to the same gpa<->phys mappings (as originally created before kexec).
[0] https://static.sched.com/hosted_files/kvmforum2019/66/VMM-fast-restart_kvmfo...
Signed-off-by: Joao Martins joao.m.martins@oracle.com Link: https://lore.kernel.org/r/20200716172913.19658-5-joao.m.martins@oracle.com Signed-off-by: Dan Williams dan.j.williams@intel.com --- drivers/dax/bus.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 64 insertions(+)
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index 7a9439132573..aa67555ba183 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -1040,6 +1040,67 @@ static ssize_t size_store(struct device *dev, struct device_attribute *attr, } static DEVICE_ATTR_RW(size);
+static ssize_t range_parse(const char *opt, size_t len, struct range *range) +{ + unsigned long long addr = 0; + char *start, *end, *str; + ssize_t rc = EINVAL; + + str = kstrdup(opt, GFP_KERNEL); + if (!str) + return rc; + + end = str; + start = strsep(&end, "-"); + if (!start || !end) + goto err; + + rc = kstrtoull(start, 16, &addr); + if (rc) + goto err; + range->start = addr; + + rc = kstrtoull(end, 16, &addr); + if (rc) + goto err; + range->end = addr; + +err: + kfree(str); + return rc; +} + +static ssize_t mapping_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t len) +{ + struct dev_dax *dev_dax = to_dev_dax(dev); + struct dax_region *dax_region = dev_dax->region; + size_t to_alloc; + struct range r; + ssize_t rc; + + rc = range_parse(buf, len, &r); + if (rc) + return rc; + + rc = -ENXIO; + device_lock(dax_region->dev); + if (!dax_region->dev->driver) { + device_unlock(dax_region->dev); + return rc; + } + device_lock(dev); + + to_alloc = range_len(&r); + if (alloc_is_aligned(dev_dax, to_alloc)) + rc = alloc_dev_dax_range(dev_dax, r.start, to_alloc); + device_unlock(dev); + device_unlock(dax_region->dev); + + return rc == 0 ? len : rc; +} +static DEVICE_ATTR_WO(mapping); + static ssize_t align_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -1181,6 +1242,8 @@ static umode_t dev_dax_visible(struct kobject *kobj, struct attribute *a, int n) return 0; if (a == &dev_attr_numa_node.attr && !IS_ENABLED(CONFIG_NUMA)) return 0; + if (a == &dev_attr_mapping.attr && is_static(dax_region)) + return 0; if ((a == &dev_attr_align.attr || a == &dev_attr_size.attr) && is_static(dax_region)) return 0444; @@ -1190,6 +1253,7 @@ static umode_t dev_dax_visible(struct kobject *kobj, struct attribute *a, int n) static struct attribute *dev_dax_attributes[] = { &dev_attr_modalias.attr, &dev_attr_size.attr, + &dev_attr_mapping.attr, &dev_attr_target_node.attr, &dev_attr_align.attr, &dev_attr_resource.attr,
On Fri, Jul 31, 2020 at 08:24:58PM -0700, Dan Williams wrote:
- Fix test_hmm and other compilation fixups (Ralph)
The hmm parts look OK
Acked-by: Jason Gunthorpe jgg@nvidia.com
Jason
dri-devel@lists.freedesktop.org
-
Dan Williams -
Jason Gunthorpe -
Randy Dunlap