From 6ad28e7e52e2bae76b1d3eb4466999d04d50db92 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Wed, 22 May 2024 14:57:13 +0200 Subject: mm/rmap: sanity check that zeropages are not passed to RMAP Using insert_page() we might have previously ended up passing the zeropage into rmap code. Make sure that won't happen again. Note that we won't check the huge zeropage for now, which might still end up in RMAP code. Link: https://lkml.kernel.org/r/20240522125713.775114-4-david@redhat.com Signed-off-by: David Hildenbrand Cc: Dan Williams Cc: Vincent Donnefort Signed-off-by: Andrew Morton --- include/linux/rmap.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux/rmap.h') diff --git a/include/linux/rmap.h b/include/linux/rmap.h index 7229b9baf20d..5cb0d419a1d7 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -200,6 +200,9 @@ static inline void __folio_rmap_sanity_checks(struct folio *folio, /* hugetlb folios are handled separately. */ VM_WARN_ON_FOLIO(folio_test_hugetlb(folio), folio); + /* When (un)mapping zeropages, we should never touch ref+mapcount. */ + VM_WARN_ON_FOLIO(is_zero_folio(folio), folio); + /* * TODO: we get driver-allocated folios that have nothing to do with * the rmap using vm_insert_page(); therefore, we cannot assume that -- cgit v1.2.3 From 1df07243483c1a32c8f2f93b06dc52a583a4dd1c Mon Sep 17 00:00:00 2001 From: Kefeng Wang Date: Fri, 24 May 2024 13:36:18 +0800 Subject: rmap: remove DEFINE_PAGE_VMA_WALK() This are no users since commit 40d707f33db5 ("mm/ksm: use folio in write_protect_page"), so remove DEFINE_PAGE_VMA_WALK(). Link: https://lkml.kernel.org/r/20240524053618.208895-1-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Reviewed-by: David Hildenbrand Cc: Alex Shi Cc: Matthew Wilcox Signed-off-by: Andrew Morton --- include/linux/rmap.h | 10 ---------- 1 file changed, 10 deletions(-) (limited to 'include/linux/rmap.h') diff --git a/include/linux/rmap.h b/include/linux/rmap.h index 5cb0d419a1d7..bb53e5920b88 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -684,16 +684,6 @@ struct page_vma_mapped_walk { unsigned int flags; }; -#define DEFINE_PAGE_VMA_WALK(name, _page, _vma, _address, _flags) \ - struct page_vma_mapped_walk name = { \ - .pfn = page_to_pfn(_page), \ - .nr_pages = compound_nr(_page), \ - .pgoff = page_to_pgoff(_page), \ - .vma = _vma, \ - .address = _address, \ - .flags = _flags, \ - } - #define DEFINE_FOLIO_VMA_WALK(name, _folio, _vma, _address, _flags) \ struct page_vma_mapped_walk name = { \ .pfn = folio_pfn(_folio), \ -- cgit v1.2.3 From 29e847d2ade3cdff36afe095fdbeb9b5f71a197a Mon Sep 17 00:00:00 2001 From: Lance Yang Date: Fri, 14 Jun 2024 09:51:37 +0800 Subject: mm/rmap: integrate PMD-mapped folio splitting into pagewalk loop In preparation for supporting try_to_unmap_one() to unmap PMD-mapped folios, start the pagewalk first, then call split_huge_pmd_address() to split the folio. Link: https://lkml.kernel.org/r/20240614015138.31461-3-ioworker0@gmail.com Signed-off-by: Lance Yang Suggested-by: David Hildenbrand Acked-by: David Hildenbrand Suggested-by: Baolin Wang Acked-by: Zi Yan Cc: Bang Li Cc: Barry Song Cc: Fangrui Song Cc: Jeff Xie Cc: Kefeng Wang Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Minchan Kim Cc: Muchun Song Cc: Peter Xu Cc: Ryan Roberts Cc: SeongJae Park Cc: Yang Shi Cc: Yin Fengwei Cc: Zach O'Keefe Signed-off-by: Andrew Morton --- include/linux/huge_mm.h | 6 ++++++ include/linux/rmap.h | 24 ++++++++++++++++++++++++ mm/huge_memory.c | 42 ++++++++++++++++++++++-------------------- mm/rmap.c | 21 +++++++++++++++------ 4 files changed, 67 insertions(+), 26 deletions(-) (limited to 'include/linux/rmap.h') diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index 7ad41de5eaea..9f720b0731c4 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -428,6 +428,9 @@ static inline bool thp_migration_supported(void) return IS_ENABLED(CONFIG_ARCH_ENABLE_THP_MIGRATION); } +void split_huge_pmd_locked(struct vm_area_struct *vma, unsigned long address, + pmd_t *pmd, bool freeze, struct folio *folio); + #else /* CONFIG_TRANSPARENT_HUGEPAGE */ static inline bool folio_test_pmd_mappable(struct folio *folio) @@ -490,6 +493,9 @@ static inline void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, unsigned long address, bool freeze, struct folio *folio) {} static inline void split_huge_pmd_address(struct vm_area_struct *vma, unsigned long address, bool freeze, struct folio *folio) {} +static inline void split_huge_pmd_locked(struct vm_area_struct *vma, + unsigned long address, pmd_t *pmd, + bool freeze, struct folio *folio) {} #define split_huge_pud(__vma, __pmd, __address) \ do { } while (0) diff --git a/include/linux/rmap.h b/include/linux/rmap.h index bb53e5920b88..bf46787c8eba 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -703,6 +703,30 @@ static inline void page_vma_mapped_walk_done(struct page_vma_mapped_walk *pvmw) spin_unlock(pvmw->ptl); } +/** + * page_vma_mapped_walk_restart - Restart the page table walk. + * @pvmw: Pointer to struct page_vma_mapped_walk. + * + * It restarts the page table walk when changes occur in the page + * table, such as splitting a PMD. Ensures that the PTL held during + * the previous walk is released and resets the state to allow for + * a new walk starting at the current address stored in pvmw->address. + */ +static inline void +page_vma_mapped_walk_restart(struct page_vma_mapped_walk *pvmw) +{ + WARN_ON_ONCE(!pvmw->pmd && !pvmw->pte); + + if (likely(pvmw->ptl)) + spin_unlock(pvmw->ptl); + else + WARN_ON_ONCE(1); + + pvmw->ptl = NULL; + pvmw->pmd = NULL; + pvmw->pte = NULL; +} + bool page_vma_mapped_walk(struct page_vma_mapped_walk *pvmw); /* diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 6b294c9160de..b247490a0931 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2583,6 +2583,27 @@ static void __split_huge_pmd_locked(struct vm_area_struct *vma, pmd_t *pmd, pmd_populate(mm, pmd, pgtable); } +void split_huge_pmd_locked(struct vm_area_struct *vma, unsigned long address, + pmd_t *pmd, bool freeze, struct folio *folio) +{ + VM_WARN_ON_ONCE(folio && !folio_test_pmd_mappable(folio)); + VM_WARN_ON_ONCE(!IS_ALIGNED(address, HPAGE_PMD_SIZE)); + VM_WARN_ON_ONCE(folio && !folio_test_locked(folio)); + VM_BUG_ON(freeze && !folio); + + /* + * When the caller requests to set up a migration entry, we + * require a folio to check the PMD against. Otherwise, there + * is a risk of replacing the wrong folio. + */ + if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd) || + is_pmd_migration_entry(*pmd)) { + if (folio && folio != pmd_folio(*pmd)) + return; + __split_huge_pmd_locked(vma, pmd, address, freeze); + } +} + void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, unsigned long address, bool freeze, struct folio *folio) { @@ -2594,26 +2615,7 @@ void __split_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, (address & HPAGE_PMD_MASK) + HPAGE_PMD_SIZE); mmu_notifier_invalidate_range_start(&range); ptl = pmd_lock(vma->vm_mm, pmd); - - /* - * If caller asks to setup a migration entry, we need a folio to check - * pmd against. Otherwise we can end up replacing wrong folio. - */ - VM_BUG_ON(freeze && !folio); - VM_WARN_ON_ONCE(folio && !folio_test_locked(folio)); - - if (pmd_trans_huge(*pmd) || pmd_devmap(*pmd) || - is_pmd_migration_entry(*pmd)) { - /* - * It's safe to call pmd_page when folio is set because it's - * guaranteed that pmd is present. - */ - if (folio && folio != pmd_folio(*pmd)) - goto out; - __split_huge_pmd_locked(vma, pmd, range.start, freeze); - } - -out: + split_huge_pmd_locked(vma, range.start, pmd, freeze, folio); spin_unlock(ptl); mmu_notifier_invalidate_range_end(&range); } diff --git a/mm/rmap.c b/mm/rmap.c index cf97a0f17752..42ffdcdfcd27 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1642,9 +1642,6 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma, if (flags & TTU_SYNC) pvmw.flags = PVMW_SYNC; - if (flags & TTU_SPLIT_HUGE_PMD) - split_huge_pmd_address(vma, address, false, folio); - /* * For THP, we have to assume the worse case ie pmd for invalidation. * For hugetlb, it could be much worse if we need to do pud @@ -1670,9 +1667,6 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma, mmu_notifier_invalidate_range_start(&range); while (page_vma_mapped_walk(&pvmw)) { - /* Unexpected PMD-mapped THP? */ - VM_BUG_ON_FOLIO(!pvmw.pte, folio); - /* * If the folio is in an mlock()d vma, we must not swap it out. */ @@ -1684,6 +1678,21 @@ static bool try_to_unmap_one(struct folio *folio, struct vm_area_struct *vma, goto walk_abort; } + if (!pvmw.pte && (flags & TTU_SPLIT_HUGE_PMD)) { + /* + * We temporarily have to drop the PTL and start once + * again from that now-PTE-mapped page table. + */ + split_huge_pmd_locked(vma, pvmw.address, pvmw.pmd, + false, folio); + flags &= ~TTU_SPLIT_HUGE_PMD; + page_vma_mapped_walk_restart(&pvmw); + continue; + } + + /* Unexpected PMD-mapped THP? */ + VM_BUG_ON_FOLIO(!pvmw.pte, folio); + pfn = pte_pfn(ptep_get(pvmw.pte)); subpage = folio_page(folio, pfn - folio_pfn(folio)); address = pvmw.address; -- cgit v1.2.3 From 3a78f77fd1fb82c32cb7971a8a97c5cbc83ab69e Mon Sep 17 00:00:00 2001 From: Miaohe Lin Date: Wed, 12 Jun 2024 15:18:32 +0800 Subject: mm/memory-failure: move some function declarations into internal.h There are some functions only used inside mm. Move them into internal.h. No functional change intended. Link: https://lkml.kernel.org/r/20240612071835.157004-11-linmiaohe@huawei.com Signed-off-by: Miaohe Lin Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202405251049.hxjwX7zO-lkp@intel.com/ Cc: Borislav Petkov (AMD) Cc: David Hildenbrand Cc: Naoya Horiguchi Cc: Tony Luck Signed-off-by: Andrew Morton --- include/linux/mm.h | 7 ------- include/linux/page-flags.h | 5 ----- include/linux/rmap.h | 2 -- mm/internal.h | 10 ++++++++++ 4 files changed, 10 insertions(+), 14 deletions(-) (limited to 'include/linux/rmap.h') diff --git a/include/linux/mm.h b/include/linux/mm.h index 8a38adaf5480..51fe207026f8 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -4000,7 +4000,6 @@ extern int __get_huge_page_for_hwpoison(unsigned long pfn, int flags, bool *migratable_cleared); void num_poisoned_pages_inc(unsigned long pfn); void num_poisoned_pages_sub(unsigned long pfn, long i); -struct task_struct *task_early_kill(struct task_struct *tsk, int force_early); #else static inline void memory_failure_queue(unsigned long pfn, int flags) { @@ -4021,12 +4020,6 @@ static inline void num_poisoned_pages_sub(unsigned long pfn, long i) } #endif -#if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_KSM) -void add_to_kill_ksm(struct task_struct *tsk, struct page *p, - struct vm_area_struct *vma, struct list_head *to_kill, - unsigned long ksm_addr); -#endif - #if defined(CONFIG_MEMORY_FAILURE) && defined(CONFIG_MEMORY_HOTPLUG) extern void memblk_nr_poison_inc(unsigned long pfn); extern void memblk_nr_poison_sub(unsigned long pfn, long i); diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index 813eea2efe26..b041bc058fb1 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -616,11 +616,6 @@ PAGEFLAG_FALSE(Uncached, uncached) PAGEFLAG(HWPoison, hwpoison, PF_ANY) TESTSCFLAG(HWPoison, hwpoison, PF_ANY) #define __PG_HWPOISON (1UL << PG_hwpoison) -#define MAGIC_HWPOISON 0x48575053U /* HWPS */ -extern void SetPageHWPoisonTakenOff(struct page *page); -extern void ClearPageHWPoisonTakenOff(struct page *page); -extern bool take_page_off_buddy(struct page *page); -extern bool put_page_back_buddy(struct page *page); #else PAGEFLAG_FALSE(HWPoison, hwpoison) #define __PG_HWPOISON 0 diff --git a/include/linux/rmap.h b/include/linux/rmap.h index bf46787c8eba..694d3d886245 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -747,8 +747,6 @@ int pfn_mkclean_range(unsigned long pfn, unsigned long nr_pages, pgoff_t pgoff, void remove_migration_ptes(struct folio *src, struct folio *dst, bool locked); -unsigned long page_mapped_in_vma(struct page *page, struct vm_area_struct *vma); - /* * rmap_walk_control: To control rmap traversing for specific needs * diff --git a/mm/internal.h b/mm/internal.h index 0a190c3c55b0..b38eecaa48dd 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -1062,6 +1062,16 @@ extern u64 hwpoison_filter_flags_mask; extern u64 hwpoison_filter_flags_value; extern u64 hwpoison_filter_memcg; extern u32 hwpoison_filter_enable; +#define MAGIC_HWPOISON 0x48575053U /* HWPS */ +void SetPageHWPoisonTakenOff(struct page *page); +void ClearPageHWPoisonTakenOff(struct page *page); +bool take_page_off_buddy(struct page *page); +bool put_page_back_buddy(struct page *page); +struct task_struct *task_early_kill(struct task_struct *tsk, int force_early); +void add_to_kill_ksm(struct task_struct *tsk, struct page *p, + struct vm_area_struct *vma, struct list_head *to_kill, + unsigned long ksm_addr); +unsigned long page_mapped_in_vma(struct page *page, struct vm_area_struct *vma); extern unsigned long __must_check vm_mmap_pgoff(struct file *, unsigned long, unsigned long, unsigned long, -- cgit v1.2.3 From a929e0d10f3db1a53668f6b9845db27d7fb63759 Mon Sep 17 00:00:00 2001 From: Kefeng Wang Date: Tue, 4 Jun 2024 19:48:22 +0800 Subject: mm: remove page_mkclean() There are no more users of page_mkclean(), remove it and update the document and comment. Link: https://lkml.kernel.org/r/20240604114822.2089819-5-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Acked-by: David Hildenbrand Cc: Daniel Vetter Cc: Helge Deller Cc: Jonathan Corbet Cc: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton --- Documentation/core-api/pin_user_pages.rst | 8 ++++---- drivers/video/fbdev/core/fb_defio.c | 4 ++-- include/linux/mm.h | 2 +- include/linux/rmap.h | 4 ---- mm/gup.c | 2 +- mm/mremap.c | 2 +- 6 files changed, 9 insertions(+), 13 deletions(-) (limited to 'include/linux/rmap.h') diff --git a/Documentation/core-api/pin_user_pages.rst b/Documentation/core-api/pin_user_pages.rst index 57b17978e156..c16ca163b55e 100644 --- a/Documentation/core-api/pin_user_pages.rst +++ b/Documentation/core-api/pin_user_pages.rst @@ -132,7 +132,7 @@ CASE 1: Direct IO (DIO) ----------------------- There are GUP references to pages that are serving as DIO buffers. These buffers are needed for a relatively short time (so they -are not "long term"). No special synchronization with page_mkclean() or +are not "long term"). No special synchronization with folio_mkclean() or munmap() is provided. Therefore, flags to set at the call site are: :: FOLL_PIN @@ -144,7 +144,7 @@ CASE 2: RDMA ------------ There are GUP references to pages that are serving as DMA buffers. These buffers are needed for a long time ("long term"). No special -synchronization with page_mkclean() or munmap() is provided. Therefore, flags +synchronization with folio_mkclean() or munmap() is provided. Therefore, flags to set at the call site are: :: FOLL_PIN | FOLL_LONGTERM @@ -170,7 +170,7 @@ callback, simply remove the range from the device's page tables. Either way, as long as the driver unpins the pages upon mmu notifier callback, then there is proper synchronization with both filesystem and mm -(page_mkclean(), munmap(), etc). Therefore, neither flag needs to be set. +(folio_mkclean(), munmap(), etc). Therefore, neither flag needs to be set. CASE 4: Pinning for struct page manipulation only ------------------------------------------------- @@ -200,7 +200,7 @@ folio_maybe_dma_pinned(): the whole point of pinning ==================================================== The whole point of marking folios as "DMA-pinned" or "gup-pinned" is to be able -to query, "is this folio DMA-pinned?" That allows code such as page_mkclean() +to query, "is this folio DMA-pinned?" That allows code such as folio_mkclean() (and file system writeback code in general) to make informed decisions about what to do when a folio cannot be unmapped due to such pins. diff --git a/drivers/video/fbdev/core/fb_defio.c b/drivers/video/fbdev/core/fb_defio.c index c9c8e294b7e7..d38998714215 100644 --- a/drivers/video/fbdev/core/fb_defio.c +++ b/drivers/video/fbdev/core/fb_defio.c @@ -113,7 +113,7 @@ static vm_fault_t fb_deferred_io_fault(struct vm_fault *vmf) printk(KERN_ERR "no mapping available\n"); BUG_ON(!page->mapping); - page->index = vmf->pgoff; /* for page_mkclean() */ + page->index = vmf->pgoff; /* for folio_mkclean() */ vmf->page = page; return 0; @@ -161,7 +161,7 @@ static vm_fault_t fb_deferred_io_track_page(struct fb_info *info, unsigned long /* * We want the page to remain locked from ->page_mkwrite until - * the PTE is marked dirty to avoid page_mkclean() being called + * the PTE is marked dirty to avoid folio_mkclean() being called * before the PTE is updated, which would leave the page ignored * by defio. * Do this by locking the page here and informing the caller diff --git a/include/linux/mm.h b/include/linux/mm.h index cb4aa725252e..101945baffc7 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1577,7 +1577,7 @@ static inline void put_page(struct page *page) * issue. * * Locking: the lockless algorithm described in folio_try_get_rcu() - * provides safe operation for get_user_pages(), page_mkclean() and + * provides safe operation for get_user_pages(), folio_mkclean() and * other calls that race to set up page table entries. */ #define GUP_PIN_COUNTING_BIAS (1U << 10) diff --git a/include/linux/rmap.h b/include/linux/rmap.h index 694d3d886245..980fa5d75d69 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -802,8 +802,4 @@ static inline int folio_mkclean(struct folio *folio) } #endif /* CONFIG_MMU */ -static inline int page_mkclean(struct page *page) -{ - return folio_mkclean(page_folio(page)); -} #endif /* _LINUX_RMAP_H */ diff --git a/mm/gup.c b/mm/gup.c index a01a0c96da31..6ff9f95a99a7 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -378,7 +378,7 @@ void unpin_user_pages_dirty_lock(struct page **pages, unsigned long npages, * 1) This code sees the page as already dirty, so it * skips the call to set_page_dirty(). That could happen * because clear_page_dirty_for_io() called - * page_mkclean(), followed by set_page_dirty(). + * folio_mkclean(), followed by set_page_dirty(). * However, now the page is going to get written back, * which meets the original intention of setting it * dirty, so all is well: clear_page_dirty_for_io() goes diff --git a/mm/mremap.c b/mm/mremap.c index 5f96bc5ee918..e7ae140fc640 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -198,7 +198,7 @@ static int move_ptes(struct vm_area_struct *vma, pmd_t *old_pmd, * PTE. * * NOTE! Both old and new PTL matter: the old one - * for racing with page_mkclean(), the new one to + * for racing with folio_mkclean(), the new one to * make sure the physical page stays valid until * the TLB entry for the old mapping has been * flushed. -- cgit v1.2.3 From 15bde4abab734c687c1f81704886aba3a70c268e Mon Sep 17 00:00:00 2001 From: Barry Song Date: Tue, 18 Jun 2024 11:11:35 +1200 Subject: mm: extend rmap flags arguments for folio_add_new_anon_rmap MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Patch series "mm: clarify folio_add_new_anon_rmap() and __folio_add_anon_rmap()", v2. This patchset is preparatory work for mTHP swapin. folio_add_new_anon_rmap() assumes that new anon rmaps are always exclusive. However, this assumption doesn’t hold true for cases like do_swap_page(), where a new anon might be added to the swapcache and is not necessarily exclusive. The patchset extends the rmap flags to allow folio_add_new_anon_rmap() to handle both exclusive and non-exclusive new anon folios. The do_swap_page() function is updated to use this extended API with rmap flags. Consequently, all new anon folios now consistently use folio_add_new_anon_rmap(). The special case for !folio_test_anon() in __folio_add_anon_rmap() can be safely removed. In conclusion, new anon folios always use folio_add_new_anon_rmap(), regardless of exclusivity. Old anon folios continue to use __folio_add_anon_rmap() via folio_add_anon_rmap_pmd() and folio_add_anon_rmap_ptes(). This patch (of 3): In the case of a swap-in, a new anonymous folio is not necessarily exclusive. This patch updates the rmap flags to allow a new anonymous folio to be treated as either exclusive or non-exclusive. To maintain the existing behavior, we always use EXCLUSIVE as the default setting. [akpm@linux-foundation.org: cleanup and constifications per David and akpm] [v-songbaohua@oppo.com: fix missing doc for flags of folio_add_new_anon_rmap()] Link: https://lkml.kernel.org/r/20240619210641.62542-1-21cnbao@gmail.com [v-songbaohua@oppo.com: enhance doc for extend rmap flags arguments for folio_add_new_anon_rmap] Link: https://lkml.kernel.org/r/20240622030256.43775-1-21cnbao@gmail.com Link: https://lkml.kernel.org/r/20240617231137.80726-1-21cnbao@gmail.com Link: https://lkml.kernel.org/r/20240617231137.80726-2-21cnbao@gmail.com Signed-off-by: Barry Song Suggested-by: David Hildenbrand Tested-by: Shuai Yuan Acked-by: David Hildenbrand Cc: Baolin Wang Cc: Chris Li Cc: "Huang, Ying" Cc: Matthew Wilcox (Oracle) Cc: Michal Hocko Cc: Ryan Roberts Cc: Suren Baghdasaryan Cc: Yang Shi Cc: Yosry Ahmed Cc: Yu Zhao Signed-off-by: Andrew Morton --- include/linux/rmap.h | 2 +- kernel/events/uprobes.c | 2 +- mm/huge_memory.c | 2 +- mm/khugepaged.c | 2 +- mm/memory.c | 10 +++++----- mm/migrate_device.c | 2 +- mm/rmap.c | 25 ++++++++++++++++--------- mm/swapfile.c | 2 +- mm/userfaultfd.c | 2 +- 9 files changed, 28 insertions(+), 21 deletions(-) (limited to 'include/linux/rmap.h') diff --git a/include/linux/rmap.h b/include/linux/rmap.h index 980fa5d75d69..0978c64f49d8 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -244,7 +244,7 @@ void folio_add_anon_rmap_ptes(struct folio *, struct page *, int nr_pages, void folio_add_anon_rmap_pmd(struct folio *, struct page *, struct vm_area_struct *, unsigned long address, rmap_t flags); void folio_add_new_anon_rmap(struct folio *, struct vm_area_struct *, - unsigned long address); + unsigned long address, rmap_t flags); void folio_add_file_rmap_ptes(struct folio *, struct page *, int nr_pages, struct vm_area_struct *); #define folio_add_file_rmap_pte(folio, page, vma) \ diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 2c83ba776fc7..c20368aa33dd 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -181,7 +181,7 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr, if (new_page) { folio_get(new_folio); - folio_add_new_anon_rmap(new_folio, vma, addr); + folio_add_new_anon_rmap(new_folio, vma, addr, RMAP_EXCLUSIVE); folio_add_lru_vma(new_folio, vma); } else /* no new page, just dec_mm_counter for old_page */ diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 46ba81240d96..14a05c643806 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -974,7 +974,7 @@ static vm_fault_t __do_huge_pmd_anonymous_page(struct vm_fault *vmf, entry = mk_huge_pmd(page, vma->vm_page_prot); entry = maybe_pmd_mkwrite(pmd_mkdirty(entry), vma); - folio_add_new_anon_rmap(folio, vma, haddr); + folio_add_new_anon_rmap(folio, vma, haddr, RMAP_EXCLUSIVE); folio_add_lru_vma(folio, vma); pgtable_trans_huge_deposit(vma->vm_mm, vmf->pmd, pgtable); set_pmd_at(vma->vm_mm, haddr, vmf->pmd, entry); diff --git a/mm/khugepaged.c b/mm/khugepaged.c index f8d08b49420c..409f67a817f1 100644 --- a/mm/khugepaged.c +++ b/mm/khugepaged.c @@ -1210,7 +1210,7 @@ static int collapse_huge_page(struct mm_struct *mm, unsigned long address, spin_lock(pmd_ptl); BUG_ON(!pmd_none(*pmd)); - folio_add_new_anon_rmap(folio, vma, address); + folio_add_new_anon_rmap(folio, vma, address, RMAP_EXCLUSIVE); folio_add_lru_vma(folio, vma); pgtable_trans_huge_deposit(mm, pmd, pgtable); set_pmd_at(mm, address, pmd, _pmd); diff --git a/mm/memory.c b/mm/memory.c index d8a0b7d2e15b..a4fc6e632d2c 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -930,7 +930,7 @@ copy_present_page(struct vm_area_struct *dst_vma, struct vm_area_struct *src_vma *prealloc = NULL; copy_user_highpage(&new_folio->page, page, addr, src_vma); __folio_mark_uptodate(new_folio); - folio_add_new_anon_rmap(new_folio, dst_vma, addr); + folio_add_new_anon_rmap(new_folio, dst_vma, addr, RMAP_EXCLUSIVE); folio_add_lru_vma(new_folio, dst_vma); rss[MM_ANONPAGES]++; @@ -3402,7 +3402,7 @@ static vm_fault_t wp_page_copy(struct vm_fault *vmf) * some TLBs while the old PTE remains in others. */ ptep_clear_flush(vma, vmf->address, vmf->pte); - folio_add_new_anon_rmap(new_folio, vma, vmf->address); + folio_add_new_anon_rmap(new_folio, vma, vmf->address, RMAP_EXCLUSIVE); folio_add_lru_vma(new_folio, vma); BUG_ON(unshare && pte_write(entry)); set_pte_at(mm, vmf->address, vmf->pte, entry); @@ -4339,7 +4339,7 @@ check_folio: /* ksm created a completely new copy */ if (unlikely(folio != swapcache && swapcache)) { - folio_add_new_anon_rmap(folio, vma, address); + folio_add_new_anon_rmap(folio, vma, address, RMAP_EXCLUSIVE); folio_add_lru_vma(folio, vma); } else { folio_add_anon_rmap_ptes(folio, page, nr_pages, vma, address, @@ -4594,7 +4594,7 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf) #ifdef CONFIG_TRANSPARENT_HUGEPAGE count_mthp_stat(folio_order(folio), MTHP_STAT_ANON_FAULT_ALLOC); #endif - folio_add_new_anon_rmap(folio, vma, addr); + folio_add_new_anon_rmap(folio, vma, addr, RMAP_EXCLUSIVE); folio_add_lru_vma(folio, vma); setpte: if (vmf_orig_pte_uffd_wp(vmf)) @@ -4792,7 +4792,7 @@ void set_pte_range(struct vm_fault *vmf, struct folio *folio, /* copy-on-write page */ if (write && !(vma->vm_flags & VM_SHARED)) { VM_BUG_ON_FOLIO(nr != 1, folio); - folio_add_new_anon_rmap(folio, vma, addr); + folio_add_new_anon_rmap(folio, vma, addr, RMAP_EXCLUSIVE); folio_add_lru_vma(folio, vma); } else { folio_add_file_rmap_ptes(folio, page, nr, vma); diff --git a/mm/migrate_device.c b/mm/migrate_device.c index 051d0a3ccbee..6d66dc1c6ffa 100644 --- a/mm/migrate_device.c +++ b/mm/migrate_device.c @@ -658,7 +658,7 @@ static void migrate_vma_insert_page(struct migrate_vma *migrate, goto unlock_abort; inc_mm_counter(mm, MM_ANONPAGES); - folio_add_new_anon_rmap(folio, vma, addr); + folio_add_new_anon_rmap(folio, vma, addr, RMAP_EXCLUSIVE); if (!folio_is_zone_device(folio)) folio_add_lru_vma(folio, vma); folio_get(folio); diff --git a/mm/rmap.c b/mm/rmap.c index 69cbd7ac2a5c..c0c99f91ade1 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1401,30 +1401,35 @@ void folio_add_anon_rmap_pmd(struct folio *folio, struct page *page, * @folio: The folio to add the mapping to. * @vma: the vm area in which the mapping is added * @address: the user virtual address mapped + * @flags: The rmap flags * * Like folio_add_anon_rmap_*() but must only be called on *new* folios. * This means the inc-and-test can be bypassed. - * The folio does not have to be locked. + * The folio doesn't necessarily need to be locked while it's exclusive + * unless two threads map it concurrently. However, the folio must be + * locked if it's shared. * - * If the folio is pmd-mappable, it is accounted as a THP. As the folio - * is new, it's assumed to be mapped exclusively by a single process. + * If the folio is pmd-mappable, it is accounted as a THP. */ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, - unsigned long address) + unsigned long address, rmap_t flags) { - int nr = folio_nr_pages(folio); + const int nr = folio_nr_pages(folio); + const bool exclusive = flags & RMAP_EXCLUSIVE; int nr_pmdmapped = 0; VM_WARN_ON_FOLIO(folio_test_hugetlb(folio), folio); + VM_WARN_ON_FOLIO(!exclusive && !folio_test_locked(folio), folio); VM_BUG_ON_VMA(address < vma->vm_start || address + (nr << PAGE_SHIFT) > vma->vm_end, vma); __folio_set_swapbacked(folio); - __folio_set_anon(folio, vma, address, true); + __folio_set_anon(folio, vma, address, exclusive); if (likely(!folio_test_large(folio))) { /* increment count (starts at -1) */ atomic_set(&folio->_mapcount, 0); - SetPageAnonExclusive(&folio->page); + if (exclusive) + SetPageAnonExclusive(&folio->page); } else if (!folio_test_pmd_mappable(folio)) { int i; @@ -1433,7 +1438,8 @@ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, /* increment count (starts at -1) */ atomic_set(&page->_mapcount, 0); - SetPageAnonExclusive(page); + if (exclusive) + SetPageAnonExclusive(page); } /* increment count (starts at -1) */ @@ -1445,7 +1451,8 @@ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, /* increment count (starts at -1) */ atomic_set(&folio->_large_mapcount, 0); atomic_set(&folio->_nr_pages_mapped, ENTIRELY_MAPPED); - SetPageAnonExclusive(&folio->page); + if (exclusive) + SetPageAnonExclusive(&folio->page); nr_pmdmapped = nr; } diff --git a/mm/swapfile.c b/mm/swapfile.c index 9c6d8e557c0f..ae1d2700f6a3 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1911,7 +1911,7 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd, folio_add_anon_rmap_pte(folio, page, vma, addr, rmap_flags); } else { /* ksm created a completely new copy */ - folio_add_new_anon_rmap(folio, vma, addr); + folio_add_new_anon_rmap(folio, vma, addr, RMAP_EXCLUSIVE); folio_add_lru_vma(folio, vma); } new_pte = pte_mkold(mk_pte(page, vma->vm_page_prot)); diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 5e7f2801698a..8dedaec00486 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -216,7 +216,7 @@ int mfill_atomic_install_pte(pmd_t *dst_pmd, folio_add_lru(folio); folio_add_file_rmap_pte(folio, page, dst_vma); } else { - folio_add_new_anon_rmap(folio, dst_vma, dst_addr); + folio_add_new_anon_rmap(folio, dst_vma, dst_addr, RMAP_EXCLUSIVE); folio_add_lru_vma(folio, dst_vma); } -- cgit v1.2.3