Remove multiple similar inline functions for dealing with different types of special swap entries.
Both migration and device private swap entries use the swap offset to store a pfn. Instead of multiple inline functions to obtain a struct page for each swap entry type use a common function pfn_swap_entry_to_page(). Also open-code the various entry_to_pfn() functions as this results is shorter code that is easier to understand.
Signed-off-by: Alistair Popple apopple@nvidia.com Reviewed-by: Ralph Campbell rcampbell@nvidia.com Reviewed-by: Christoph Hellwig hch@lst.de
---
v11: * Rebased on mmotm
v9: * Rebased on v5.13-rc2
v8: * No changes
v7: * Reworded commit message to include pfn_swap_entry_to_page() * Added Christoph's Reviewed-by
v6: * Removed redundant compound_page() call from inside PageLocked() * Fixed a minor build issue for s390 reported by kernel test bot
v4: * Added pfn_swap_entry_to_page() * Reinstated check that migration entries point to locked pages * Removed #define swapcache_prepare which isn't needed for CONFIG_SWAP=0 builds --- arch/s390/mm/pgtable.c | 2 +- fs/proc/task_mmu.c | 23 +++++--------- include/linux/swap.h | 4 +-- include/linux/swapops.h | 69 ++++++++++++++--------------------------- mm/hmm.c | 5 ++- mm/huge_memory.c | 6 ++-- mm/memcontrol.c | 2 +- mm/memory.c | 10 +++--- mm/migrate.c | 6 ++-- mm/page_vma_mapped.c | 6 ++-- 10 files changed, 51 insertions(+), 82 deletions(-)
diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c index 18205f851c24..eec3a9d7176e 100644 --- a/arch/s390/mm/pgtable.c +++ b/arch/s390/mm/pgtable.c @@ -691,7 +691,7 @@ static void ptep_zap_swap_entry(struct mm_struct *mm, swp_entry_t entry) if (!non_swap_entry(entry)) dec_mm_counter(mm, MM_SWAPENTS); else if (is_migration_entry(entry)) { - struct page *page = migration_entry_to_page(entry); + struct page *page = pfn_swap_entry_to_page(entry);
dec_mm_counter(mm, mm_counter(page)); } diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 95c8f1e8fea6..eb97468dfe4c 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -514,10 +514,8 @@ static void smaps_pte_entry(pte_t *pte, unsigned long addr, } else { mss->swap_pss += (u64)PAGE_SIZE << PSS_SHIFT; } - } else if (is_migration_entry(swpent)) - page = migration_entry_to_page(swpent); - else if (is_device_private_entry(swpent)) - page = device_private_entry_to_page(swpent); + } else if (is_pfn_swap_entry(swpent)) + page = pfn_swap_entry_to_page(swpent); } else if (unlikely(IS_ENABLED(CONFIG_SHMEM) && mss->check_shmem_swap && pte_none(*pte))) { page = xa_load(&vma->vm_file->f_mapping->i_pages, @@ -549,7 +547,7 @@ static void smaps_pmd_entry(pmd_t *pmd, unsigned long addr, swp_entry_t entry = pmd_to_swp_entry(*pmd);
if (is_migration_entry(entry)) - page = migration_entry_to_page(entry); + page = pfn_swap_entry_to_page(entry); } if (IS_ERR_OR_NULL(page)) return; @@ -694,10 +692,8 @@ static int smaps_hugetlb_range(pte_t *pte, unsigned long hmask, } else if (is_swap_pte(*pte)) { swp_entry_t swpent = pte_to_swp_entry(*pte);
- if (is_migration_entry(swpent)) - page = migration_entry_to_page(swpent); - else if (is_device_private_entry(swpent)) - page = device_private_entry_to_page(swpent); + if (is_pfn_swap_entry(swpent)) + page = pfn_swap_entry_to_page(swpent); } if (page) { int mapcount = page_mapcount(page); @@ -1389,11 +1385,8 @@ static pagemap_entry_t pte_to_pagemap_entry(struct pagemapread *pm, frame = swp_type(entry) | (swp_offset(entry) << MAX_SWAPFILES_SHIFT); flags |= PM_SWAP; - if (is_migration_entry(entry)) - page = migration_entry_to_page(entry); - - if (is_device_private_entry(entry)) - page = device_private_entry_to_page(entry); + if (is_pfn_swap_entry(entry)) + page = pfn_swap_entry_to_page(entry); }
if (page && !PageAnon(page)) @@ -1454,7 +1447,7 @@ static int pagemap_pmd_range(pmd_t *pmdp, unsigned long addr, unsigned long end, if (pmd_swp_uffd_wp(pmd)) flags |= PM_UFFD_WP; VM_BUG_ON(!is_pmd_migration_entry(pmd)); - page = migration_entry_to_page(entry); + page = pfn_swap_entry_to_page(entry); } #endif
diff --git a/include/linux/swap.h b/include/linux/swap.h index ac9bd84c905e..df7cbb6b3d3e 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -564,8 +564,8 @@ static inline void show_swap_cache_info(void) { }
-#define free_swap_and_cache(e) ({(is_migration_entry(e) || is_device_private_entry(e));}) -#define swapcache_prepare(e) ({(is_migration_entry(e) || is_device_private_entry(e));}) +/* used to sanity check ptes in zap_pte_range when CONFIG_SWAP=0 */ +#define free_swap_and_cache(e) is_pfn_swap_entry(e)
static inline int add_swap_count_continuation(swp_entry_t swp, gfp_t gfp_mask) { diff --git a/include/linux/swapops.h b/include/linux/swapops.h index 708fbeb21dd3..c24c79812bc1 100644 --- a/include/linux/swapops.h +++ b/include/linux/swapops.h @@ -128,16 +128,6 @@ static inline bool is_write_device_private_entry(swp_entry_t entry) { return unlikely(swp_type(entry) == SWP_DEVICE_WRITE); } - -static inline unsigned long device_private_entry_to_pfn(swp_entry_t entry) -{ - return swp_offset(entry); -} - -static inline struct page *device_private_entry_to_page(swp_entry_t entry) -{ - return pfn_to_page(swp_offset(entry)); -} #else /* CONFIG_DEVICE_PRIVATE */ static inline swp_entry_t make_device_private_entry(struct page *page, bool write) { @@ -157,16 +147,6 @@ static inline bool is_write_device_private_entry(swp_entry_t entry) { return false; } - -static inline unsigned long device_private_entry_to_pfn(swp_entry_t entry) -{ - return 0; -} - -static inline struct page *device_private_entry_to_page(swp_entry_t entry) -{ - return NULL; -} #endif /* CONFIG_DEVICE_PRIVATE */
#ifdef CONFIG_MIGRATION @@ -189,22 +169,6 @@ static inline int is_write_migration_entry(swp_entry_t entry) return unlikely(swp_type(entry) == SWP_MIGRATION_WRITE); }
-static inline unsigned long migration_entry_to_pfn(swp_entry_t entry) -{ - return swp_offset(entry); -} - -static inline struct page *migration_entry_to_page(swp_entry_t entry) -{ - struct page *p = pfn_to_page(swp_offset(entry)); - /* - * Any use of migration entries may only occur while the - * corresponding page is locked - */ - BUG_ON(!PageLocked(compound_head(p))); - return p; -} - static inline void make_migration_entry_read(swp_entry_t *entry) { *entry = swp_entry(SWP_MIGRATION_READ, swp_offset(*entry)); @@ -224,16 +188,6 @@ static inline int is_migration_entry(swp_entry_t swp) return 0; }
-static inline unsigned long migration_entry_to_pfn(swp_entry_t entry) -{ - return 0; -} - -static inline struct page *migration_entry_to_page(swp_entry_t entry) -{ - return NULL; -} - static inline void make_migration_entry_read(swp_entry_t *entryp) { } static inline void __migration_entry_wait(struct mm_struct *mm, pte_t *ptep, spinlock_t *ptl) { } @@ -248,6 +202,29 @@ static inline int is_write_migration_entry(swp_entry_t entry)
#endif
+static inline struct page *pfn_swap_entry_to_page(swp_entry_t entry) +{ + struct page *p = pfn_to_page(swp_offset(entry)); + + /* + * Any use of migration entries may only occur while the + * corresponding page is locked + */ + BUG_ON(is_migration_entry(entry) && !PageLocked(p)); + + return p; +} + +/* + * A pfn swap entry is a special type of swap entry that always has a pfn stored + * in the swap offset. They are used to represent unaddressable device memory + * and to restrict access to a page undergoing migration. + */ +static inline bool is_pfn_swap_entry(swp_entry_t entry) +{ + return is_migration_entry(entry) || is_device_private_entry(entry); +} + struct page_vma_mapped_walk;
#ifdef CONFIG_ARCH_ENABLE_THP_MIGRATION diff --git a/mm/hmm.c b/mm/hmm.c index 943cb2ba4442..3b2dda71d0ed 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -214,7 +214,7 @@ static inline bool hmm_is_device_private_entry(struct hmm_range *range, swp_entry_t entry) { return is_device_private_entry(entry) && - device_private_entry_to_page(entry)->pgmap->owner == + pfn_swap_entry_to_page(entry)->pgmap->owner == range->dev_private_owner; }
@@ -257,8 +257,7 @@ static int hmm_vma_handle_pte(struct mm_walk *walk, unsigned long addr, cpu_flags = HMM_PFN_VALID; if (is_write_device_private_entry(entry)) cpu_flags |= HMM_PFN_WRITE; - *hmm_pfn = device_private_entry_to_pfn(entry) | - cpu_flags; + *hmm_pfn = swp_offset(entry) | cpu_flags; return 0; }
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index d513b0cd1161..327b8d9d8d2f 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1643,7 +1643,7 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma,
VM_BUG_ON(!is_pmd_migration_entry(orig_pmd)); entry = pmd_to_swp_entry(orig_pmd); - page = migration_entry_to_page(entry); + page = pfn_swap_entry_to_page(entry); flush_needed = 0; } else WARN_ONCE(1, "Non present huge pmd without pmd migration enabled!"); @@ -2012,7 +2012,7 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, swp_entry_t entry;
entry = pmd_to_swp_entry(old_pmd); - page = migration_entry_to_page(entry); + page = pfn_swap_entry_to_page(entry); } else { page = pmd_page(old_pmd); if (!PageDirty(page) && pmd_dirty(old_pmd)) @@ -2066,7 +2066,7 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, swp_entry_t entry;
entry = pmd_to_swp_entry(old_pmd); - page = migration_entry_to_page(entry); + page = pfn_swap_entry_to_page(entry); write = is_write_migration_entry(entry); young = false; soft_dirty = pmd_swp_soft_dirty(old_pmd); diff --git a/mm/memcontrol.c b/mm/memcontrol.c index dce5154fbb8f..ae1f5d0cb581 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -5537,7 +5537,7 @@ static struct page *mc_handle_swap_pte(struct vm_area_struct *vma, * as special swap entry in the CPU page table. */ if (is_device_private_entry(ent)) { - page = device_private_entry_to_page(ent); + page = pfn_swap_entry_to_page(ent); /* * MEMORY_DEVICE_PRIVATE means ZONE_DEVICE page and which have * a refcount of 1 when free (unlike normal page) diff --git a/mm/memory.c b/mm/memory.c index a5af7d854776..a6c5132354a2 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -729,7 +729,7 @@ copy_nonpresent_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm, } rss[MM_SWAPENTS]++; } else if (is_migration_entry(entry)) { - page = migration_entry_to_page(entry); + page = pfn_swap_entry_to_page(entry);
rss[mm_counter(page)]++;
@@ -748,7 +748,7 @@ copy_nonpresent_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm, set_pte_at(src_mm, addr, src_pte, pte); } } else if (is_device_private_entry(entry)) { - page = device_private_entry_to_page(entry); + page = pfn_swap_entry_to_page(entry);
/* * Update rss count even for unaddressable pages, as @@ -1280,7 +1280,7 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb,
entry = pte_to_swp_entry(ptent); if (is_device_private_entry(entry)) { - struct page *page = device_private_entry_to_page(entry); + struct page *page = pfn_swap_entry_to_page(entry);
if (unlikely(details && details->check_mapping)) { /* @@ -1309,7 +1309,7 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb, else if (is_migration_entry(entry)) { struct page *page;
- page = migration_entry_to_page(entry); + page = pfn_swap_entry_to_page(entry); rss[mm_counter(page)]--; } if (unlikely(!free_swap_and_cache(entry))) @@ -3372,7 +3372,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) migration_entry_wait(vma->vm_mm, vmf->pmd, vmf->address); } else if (is_device_private_entry(entry)) { - vmf->page = device_private_entry_to_page(entry); + vmf->page = pfn_swap_entry_to_page(entry); ret = vmf->page->pgmap->ops->migrate_to_ram(vmf); } else if (is_hwpoison_entry(entry)) { ret = VM_FAULT_HWPOISON; diff --git a/mm/migrate.c b/mm/migrate.c index 8810c1421f5d..b4abb87249e1 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -296,7 +296,7 @@ void __migration_entry_wait(struct mm_struct *mm, pte_t *ptep, if (!is_migration_entry(entry)) goto out;
- page = migration_entry_to_page(entry); + page = pfn_swap_entry_to_page(entry); page = compound_head(page);
/* @@ -337,7 +337,7 @@ void pmd_migration_entry_wait(struct mm_struct *mm, pmd_t *pmd) ptl = pmd_lock(mm, pmd); if (!is_pmd_migration_entry(*pmd)) goto unlock; - page = migration_entry_to_page(pmd_to_swp_entry(*pmd)); + page = pfn_swap_entry_to_page(pmd_to_swp_entry(*pmd)); if (!get_page_unless_zero(page)) goto unlock; spin_unlock(ptl); @@ -2289,7 +2289,7 @@ static int migrate_vma_collect_pmd(pmd_t *pmdp, if (!is_device_private_entry(entry)) goto next;
- page = device_private_entry_to_page(entry); + page = pfn_swap_entry_to_page(entry); if (!(migrate->flags & MIGRATE_VMA_SELECT_DEVICE_PRIVATE) || page->pgmap->owner != migrate->pgmap_owner) diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c index 3dd350a941aa..082e8073af56 100644 --- a/mm/page_vma_mapped.c +++ b/mm/page_vma_mapped.c @@ -96,7 +96,7 @@ static bool check_pte(struct page_vma_mapped_walk *pvmw) if (!is_migration_entry(entry)) return false;
- pfn = migration_entry_to_pfn(entry); + pfn = swp_offset(entry); } else if (is_swap_pte(*pvmw->pte)) { swp_entry_t entry;
@@ -105,7 +105,7 @@ static bool check_pte(struct page_vma_mapped_walk *pvmw) if (!is_device_private_entry(entry)) return false;
- pfn = device_private_entry_to_pfn(entry); + pfn = swp_offset(entry); } else { if (!pte_present(*pvmw->pte)) return false; @@ -233,7 +233,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw) return not_found(pvmw); entry = pmd_to_swp_entry(pmde); if (!is_migration_entry(entry) || - migration_entry_to_page(entry) != page) + pfn_swap_entry_to_page(entry) != page) return not_found(pvmw); return true; }