From: Oleksandr Andrushchenko oleksandr_andrushchenko@epam.com
This is in preparation for adding support of DMA buffer functionality: make map/unmap related code and structures, used privately by gntdev, ready for dma-buf extension, which will re-use these. Rename corresponding structures as those become non-private to gntdev now.
Signed-off-by: Oleksandr Andrushchenko oleksandr_andrushchenko@epam.com Reviewed-by: Boris Ostrovsky boris.ostrovsky@oracle.com --- drivers/xen/gntdev-common.h | 88 +++++++++++++++++++++++ drivers/xen/gntdev.c | 134 ++++++++++++------------------------ 2 files changed, 131 insertions(+), 91 deletions(-) create mode 100644 drivers/xen/gntdev-common.h
diff --git a/drivers/xen/gntdev-common.h b/drivers/xen/gntdev-common.h new file mode 100644 index 000000000000..2346c198f72e --- /dev/null +++ b/drivers/xen/gntdev-common.h @@ -0,0 +1,88 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* + * Common functionality of grant device. + * + * Copyright (c) 2006-2007, D G Murray. + * (c) 2009 Gerd Hoffmann kraxel@redhat.com + * (c) 2018 Oleksandr Andrushchenko, EPAM Systems Inc. + */ + +#ifndef _GNTDEV_COMMON_H +#define _GNTDEV_COMMON_H + +#include <linux/mm.h> +#include <linux/mman.h> +#include <linux/mmu_notifier.h> +#include <linux/types.h> + +struct gntdev_priv { + /* Maps with visible offsets in the file descriptor. */ + struct list_head maps; + /* + * Maps that are not visible; will be freed on munmap. + * Only populated if populate_freeable_maps == 1 + */ + struct list_head freeable_maps; + /* lock protects maps and freeable_maps. */ + struct mutex lock; + struct mm_struct *mm; + struct mmu_notifier mn; + +#ifdef CONFIG_XEN_GRANT_DMA_ALLOC + /* Device for which DMA memory is allocated. */ + struct device *dma_dev; +#endif +}; + +struct gntdev_unmap_notify { + int flags; + /* Address relative to the start of the gntdev_grant_map. */ + int addr; + int event; +}; + +struct gntdev_grant_map { + struct list_head next; + struct vm_area_struct *vma; + int index; + int count; + int flags; + refcount_t users; + struct gntdev_unmap_notify notify; + struct ioctl_gntdev_grant_ref *grants; + struct gnttab_map_grant_ref *map_ops; + struct gnttab_unmap_grant_ref *unmap_ops; + struct gnttab_map_grant_ref *kmap_ops; + struct gnttab_unmap_grant_ref *kunmap_ops; + struct page **pages; + unsigned long pages_vm_start; + +#ifdef CONFIG_XEN_GRANT_DMA_ALLOC + /* + * If dmabuf_vaddr is not NULL then this mapping is backed by DMA + * capable memory. + */ + + struct device *dma_dev; + /* Flags used to create this DMA buffer: GNTDEV_DMA_FLAG_XXX. */ + int dma_flags; + void *dma_vaddr; + dma_addr_t dma_bus_addr; + /* Needed to avoid allocation in gnttab_dma_free_pages(). */ + xen_pfn_t *frames; +#endif +}; + +struct gntdev_grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count, + int dma_flags); + +void gntdev_add_map(struct gntdev_priv *priv, struct gntdev_grant_map *add); + +void gntdev_put_map(struct gntdev_priv *priv, struct gntdev_grant_map *map); + +bool gntdev_account_mapped_pages(int count); + +int gntdev_map_grant_pages(struct gntdev_grant_map *map); + +#endif diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c index 173332f439d8..e03f50052f3e 100644 --- a/drivers/xen/gntdev.c +++ b/drivers/xen/gntdev.c @@ -6,6 +6,7 @@ * * Copyright (c) 2006-2007, D G Murray. * (c) 2009 Gerd Hoffmann kraxel@redhat.com + * (c) 2018 Oleksandr Andrushchenko, EPAM Systems Inc. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of @@ -26,10 +27,6 @@ #include <linux/init.h> #include <linux/miscdevice.h> #include <linux/fs.h> -#include <linux/mm.h> -#include <linux/mman.h> -#include <linux/mmu_notifier.h> -#include <linux/types.h> #include <linux/uaccess.h> #include <linux/sched.h> #include <linux/sched/mm.h> @@ -50,6 +47,8 @@ #include <asm/xen/hypervisor.h> #include <asm/xen/hypercall.h>
+#include "gntdev-common.h" + MODULE_LICENSE("GPL"); MODULE_AUTHOR("Derek G. Murray Derek.Murray@cl.cam.ac.uk, " "Gerd Hoffmann kraxel@redhat.com"); @@ -65,73 +64,23 @@ static atomic_t pages_mapped = ATOMIC_INIT(0); static int use_ptemod; #define populate_freeable_maps use_ptemod
-struct gntdev_priv { - /* maps with visible offsets in the file descriptor */ - struct list_head maps; - /* maps that are not visible; will be freed on munmap. - * Only populated if populate_freeable_maps == 1 */ - struct list_head freeable_maps; - /* lock protects maps and freeable_maps */ - struct mutex lock; - struct mm_struct *mm; - struct mmu_notifier mn; - -#ifdef CONFIG_XEN_GRANT_DMA_ALLOC - /* Device for which DMA memory is allocated. */ - struct device *dma_dev; -#endif -}; - -struct unmap_notify { - int flags; - /* Address relative to the start of the grant_map */ - int addr; - int event; -}; - -struct grant_map { - struct list_head next; - struct vm_area_struct *vma; - int index; - int count; - int flags; - refcount_t users; - struct unmap_notify notify; - struct ioctl_gntdev_grant_ref *grants; - struct gnttab_map_grant_ref *map_ops; - struct gnttab_unmap_grant_ref *unmap_ops; - struct gnttab_map_grant_ref *kmap_ops; - struct gnttab_unmap_grant_ref *kunmap_ops; - struct page **pages; - unsigned long pages_vm_start; - -#ifdef CONFIG_XEN_GRANT_DMA_ALLOC - /* - * If dmabuf_vaddr is not NULL then this mapping is backed by DMA - * capable memory. - */ - - struct device *dma_dev; - /* Flags used to create this DMA buffer: GNTDEV_DMA_FLAG_XXX. */ - int dma_flags; - void *dma_vaddr; - dma_addr_t dma_bus_addr; - /* Needed to avoid allocation in gnttab_dma_free_pages(). */ - xen_pfn_t *frames; -#endif -}; - -static int unmap_grant_pages(struct grant_map *map, int offset, int pages); +static int unmap_grant_pages(struct gntdev_grant_map *map, + int offset, int pages);
static struct miscdevice gntdev_miscdev;
/* ------------------------------------------------------------------ */
+bool gntdev_account_mapped_pages(int count) +{ + return atomic_add_return(count, &pages_mapped) > limit; +} + static void gntdev_print_maps(struct gntdev_priv *priv, char *text, int text_index) { #ifdef DEBUG - struct grant_map *map; + struct gntdev_grant_map *map;
pr_debug("%s: maps list (priv %p)\n", __func__, priv); list_for_each_entry(map, &priv->maps, next) @@ -141,7 +90,7 @@ static void gntdev_print_maps(struct gntdev_priv *priv, #endif }
-static void gntdev_free_map(struct grant_map *map) +static void gntdev_free_map(struct gntdev_grant_map *map) { if (map == NULL) return; @@ -176,13 +125,13 @@ static void gntdev_free_map(struct grant_map *map) kfree(map); }
-static struct grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count, +struct gntdev_grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count, int dma_flags) { - struct grant_map *add; + struct gntdev_grant_map *add; int i;
- add = kzalloc(sizeof(struct grant_map), GFP_KERNEL); + add = kzalloc(sizeof(*add), GFP_KERNEL); if (NULL == add) return NULL;
@@ -252,9 +201,9 @@ static struct grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count, return NULL; }
-static void gntdev_add_map(struct gntdev_priv *priv, struct grant_map *add) +void gntdev_add_map(struct gntdev_priv *priv, struct gntdev_grant_map *add) { - struct grant_map *map; + struct gntdev_grant_map *map;
list_for_each_entry(map, &priv->maps, next) { if (add->index + add->count < map->index) { @@ -269,10 +218,10 @@ static void gntdev_add_map(struct gntdev_priv *priv, struct grant_map *add) gntdev_print_maps(priv, "[new]", add->index); }
-static struct grant_map *gntdev_find_map_index(struct gntdev_priv *priv, - int index, int count) +static struct gntdev_grant_map *gntdev_find_map_index(struct gntdev_priv *priv, + int index, int count) { - struct grant_map *map; + struct gntdev_grant_map *map;
list_for_each_entry(map, &priv->maps, next) { if (map->index != index) @@ -284,7 +233,7 @@ static struct grant_map *gntdev_find_map_index(struct gntdev_priv *priv, return NULL; }
-static void gntdev_put_map(struct gntdev_priv *priv, struct grant_map *map) +void gntdev_put_map(struct gntdev_priv *priv, struct gntdev_grant_map *map) { if (!map) return; @@ -315,7 +264,7 @@ static void gntdev_put_map(struct gntdev_priv *priv, struct grant_map *map) static int find_grant_ptes(pte_t *pte, pgtable_t token, unsigned long addr, void *data) { - struct grant_map *map = data; + struct gntdev_grant_map *map = data; unsigned int pgnr = (addr - map->vma->vm_start) >> PAGE_SHIFT; int flags = map->flags | GNTMAP_application_map | GNTMAP_contains_pte; u64 pte_maddr; @@ -348,7 +297,7 @@ static int set_grant_ptes_as_special(pte_t *pte, pgtable_t token, } #endif
-static int map_grant_pages(struct grant_map *map) +int gntdev_map_grant_pages(struct gntdev_grant_map *map) { int i, err = 0;
@@ -413,7 +362,8 @@ static int map_grant_pages(struct grant_map *map) return err; }
-static int __unmap_grant_pages(struct grant_map *map, int offset, int pages) +static int __unmap_grant_pages(struct gntdev_grant_map *map, int offset, + int pages) { int i, err = 0; struct gntab_unmap_queue_data unmap_data; @@ -448,7 +398,8 @@ static int __unmap_grant_pages(struct grant_map *map, int offset, int pages) return err; }
-static int unmap_grant_pages(struct grant_map *map, int offset, int pages) +static int unmap_grant_pages(struct gntdev_grant_map *map, int offset, + int pages) { int range, err = 0;
@@ -480,7 +431,7 @@ static int unmap_grant_pages(struct grant_map *map, int offset, int pages)
static void gntdev_vma_open(struct vm_area_struct *vma) { - struct grant_map *map = vma->vm_private_data; + struct gntdev_grant_map *map = vma->vm_private_data;
pr_debug("gntdev_vma_open %p\n", vma); refcount_inc(&map->users); @@ -488,7 +439,7 @@ static void gntdev_vma_open(struct vm_area_struct *vma)
static void gntdev_vma_close(struct vm_area_struct *vma) { - struct grant_map *map = vma->vm_private_data; + struct gntdev_grant_map *map = vma->vm_private_data; struct file *file = vma->vm_file; struct gntdev_priv *priv = file->private_data;
@@ -512,7 +463,7 @@ static void gntdev_vma_close(struct vm_area_struct *vma) static struct page *gntdev_vma_find_special_page(struct vm_area_struct *vma, unsigned long addr) { - struct grant_map *map = vma->vm_private_data; + struct gntdev_grant_map *map = vma->vm_private_data;
return map->pages[(addr - map->pages_vm_start) >> PAGE_SHIFT]; } @@ -525,7 +476,7 @@ static const struct vm_operations_struct gntdev_vmops = {
/* ------------------------------------------------------------------ */
-static void unmap_if_in_range(struct grant_map *map, +static void unmap_if_in_range(struct gntdev_grant_map *map, unsigned long start, unsigned long end) { unsigned long mstart, mend; @@ -554,7 +505,7 @@ static void mn_invl_range_start(struct mmu_notifier *mn, unsigned long start, unsigned long end) { struct gntdev_priv *priv = container_of(mn, struct gntdev_priv, mn); - struct grant_map *map; + struct gntdev_grant_map *map;
mutex_lock(&priv->lock); list_for_each_entry(map, &priv->maps, next) { @@ -570,7 +521,7 @@ static void mn_release(struct mmu_notifier *mn, struct mm_struct *mm) { struct gntdev_priv *priv = container_of(mn, struct gntdev_priv, mn); - struct grant_map *map; + struct gntdev_grant_map *map; int err;
mutex_lock(&priv->lock); @@ -651,13 +602,14 @@ static int gntdev_open(struct inode *inode, struct file *flip) static int gntdev_release(struct inode *inode, struct file *flip) { struct gntdev_priv *priv = flip->private_data; - struct grant_map *map; + struct gntdev_grant_map *map;
pr_debug("priv %p\n", priv);
mutex_lock(&priv->lock); while (!list_empty(&priv->maps)) { - map = list_entry(priv->maps.next, struct grant_map, next); + map = list_entry(priv->maps.next, + struct gntdev_grant_map, next); list_del(&map->next); gntdev_put_map(NULL /* already removed */, map); } @@ -674,7 +626,7 @@ static long gntdev_ioctl_map_grant_ref(struct gntdev_priv *priv, struct ioctl_gntdev_map_grant_ref __user *u) { struct ioctl_gntdev_map_grant_ref op; - struct grant_map *map; + struct gntdev_grant_map *map; int err;
if (copy_from_user(&op, u, sizeof(op)) != 0) @@ -688,7 +640,7 @@ static long gntdev_ioctl_map_grant_ref(struct gntdev_priv *priv, if (!map) return err;
- if (unlikely(atomic_add_return(op.count, &pages_mapped) > limit)) { + if (unlikely(gntdev_account_mapped_pages(op.count))) { pr_debug("can't map: over limit\n"); gntdev_put_map(NULL, map); return err; @@ -715,7 +667,7 @@ static long gntdev_ioctl_unmap_grant_ref(struct gntdev_priv *priv, struct ioctl_gntdev_unmap_grant_ref __user *u) { struct ioctl_gntdev_unmap_grant_ref op; - struct grant_map *map; + struct gntdev_grant_map *map; int err = -ENOENT;
if (copy_from_user(&op, u, sizeof(op)) != 0) @@ -741,7 +693,7 @@ static long gntdev_ioctl_get_offset_for_vaddr(struct gntdev_priv *priv, { struct ioctl_gntdev_get_offset_for_vaddr op; struct vm_area_struct *vma; - struct grant_map *map; + struct gntdev_grant_map *map; int rv = -EINVAL;
if (copy_from_user(&op, u, sizeof(op)) != 0) @@ -772,7 +724,7 @@ static long gntdev_ioctl_get_offset_for_vaddr(struct gntdev_priv *priv, static long gntdev_ioctl_notify(struct gntdev_priv *priv, void __user *u) { struct ioctl_gntdev_unmap_notify op; - struct grant_map *map; + struct gntdev_grant_map *map; int rc; int out_flags; unsigned int out_event; @@ -1070,7 +1022,7 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma) struct gntdev_priv *priv = flip->private_data; int index = vma->vm_pgoff; int count = vma_pages(vma); - struct grant_map *map; + struct gntdev_grant_map *map; int i, err = -EINVAL;
if ((vma->vm_flags & VM_WRITE) && !(vma->vm_flags & VM_SHARED)) @@ -1127,7 +1079,7 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma) } }
- err = map_grant_pages(map); + err = gntdev_map_grant_pages(map); if (err) goto out_put_map;