From: "Matthew Wilcox (Oracle)" willy@infradead.org
mainline inclusion from mainline-v6.8-rc1 commit 96db66d9c8f3c1547325af01b1f328b85d6ee1b9 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/IAJ5MT
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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Patch series "Finish two folio conversions".
Most callers of page_add_new_anon_rmap() and lru_cache_add_inactive_or_unevictable() have been converted to their folio equivalents, but there are still a few stragglers. There's a bit of preparatory work in ksm and unuse_pte(), but after that it's pretty mechanical.
This patch (of 9):
Accept a folio as an argument and return a folio result. Removes a call to compound_head() in do_swap_page(), and prevents folio & page from getting out of sync in unuse_pte().
Reviewed-by: David Hildenbrand david@redhat.com [willy@infradead.org: fix smatch warning] Link: https://lkml.kernel.org/r/ZXnPtblC6A1IkyAB@casper.infradead.org [david@redhat.com: only adjust the page if the folio changed] Link: https://lkml.kernel.org/r/6a8f2110-fa91-4c10-9eae-88315309a6e3@redhat.com Link: https://lkml.kernel.org/r/20231211162214.2146080-1-willy@infradead.org Link: https://lkml.kernel.org/r/20231211162214.2146080-2-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) willy@infradead.org Signed-off-by: David Hildenbrand david@redhat.com Signed-off-by: Andrew Morton akpm@linux-foundation.org [ Dep-of: f00f48436c78 ] Signed-off-by: Liu Shixin liushixin2@huawei.com --- include/linux/ksm.h | 6 +++--- mm/ksm.c | 21 +++++++++++---------- mm/memory.c | 11 +++++++---- mm/swapfile.c | 8 +++++--- 4 files changed, 26 insertions(+), 20 deletions(-)
diff --git a/include/linux/ksm.h b/include/linux/ksm.h index 2774e5c235009..d6225305fb7d1 100644 --- a/include/linux/ksm.h +++ b/include/linux/ksm.h @@ -76,7 +76,7 @@ static inline void ksm_exit(struct mm_struct *mm) * We'd like to make this conditional on vma->vm_flags & VM_MERGEABLE, * but what if the vma was unmerged while the page was swapped out? */ -struct page *ksm_might_need_to_copy(struct page *page, +struct folio *ksm_might_need_to_copy(struct folio *folio, struct vm_area_struct *vma, unsigned long addr);
void rmap_walk_ksm(struct folio *folio, struct rmap_walk_control *rwc); @@ -127,10 +127,10 @@ static inline int ksm_madvise(struct vm_area_struct *vma, unsigned long start, return 0; }
-static inline struct page *ksm_might_need_to_copy(struct page *page, +static inline struct folio *ksm_might_need_to_copy(struct folio *folio, struct vm_area_struct *vma, unsigned long addr) { - return page; + return folio; }
static inline void rmap_walk_ksm(struct folio *folio, diff --git a/mm/ksm.c b/mm/ksm.c index 8ecbf01041d24..de0de7ba1d6b1 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -2793,30 +2793,30 @@ void __ksm_exit(struct mm_struct *mm) trace_ksm_exit(mm); }
-struct page *ksm_might_need_to_copy(struct page *page, +struct folio *ksm_might_need_to_copy(struct folio *folio, struct vm_area_struct *vma, unsigned long addr) { - struct folio *folio = page_folio(page); + struct page *page = folio_page(folio, 0); struct anon_vma *anon_vma = folio_anon_vma(folio); struct folio *new_folio;
if (folio_test_large(folio)) - return page; + return folio;
if (folio_test_ksm(folio)) { if (folio_stable_node(folio) && !(ksm_run & KSM_RUN_UNMERGE)) - return page; /* no need to copy it */ + return folio; /* no need to copy it */ } else if (!anon_vma) { - return page; /* no need to copy it */ + return folio; /* no need to copy it */ } else if (folio->index == linear_page_index(vma, addr) && anon_vma->root == vma->anon_vma->root) { - return page; /* still no need to copy it */ + return folio; /* still no need to copy it */ } if (PageHWPoison(page)) return ERR_PTR(-EHWPOISON); if (!folio_test_uptodate(folio)) - return page; /* let do_swap_page report the error */ + return folio; /* let do_swap_page report the error */
new_folio = vma_alloc_folio(GFP_HIGHUSER_MOVABLE, 0, vma, addr, false); if (new_folio && @@ -2825,9 +2825,10 @@ struct page *ksm_might_need_to_copy(struct page *page, new_folio = NULL; } if (new_folio) { - if (copy_mc_user_highpage(&new_folio->page, page, addr, vma)) { + if (copy_mc_user_highpage(folio_page(new_folio, 0), page, + addr, vma)) { folio_put(new_folio); - memory_failure_queue(page_to_pfn(page), 0); + memory_failure_queue(folio_pfn(folio), 0); return ERR_PTR(-EHWPOISON); } folio_set_dirty(new_folio); @@ -2838,7 +2839,7 @@ struct page *ksm_might_need_to_copy(struct page *page, #endif }
- return new_folio ? &new_folio->page : NULL; + return new_folio; }
void rmap_walk_ksm(struct folio *folio, struct rmap_walk_control *rwc) diff --git a/mm/memory.c b/mm/memory.c index 3bd587be33c1b..e212cfdb5c5b0 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4122,15 +4122,18 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) * page->index of !PageKSM() pages would be nonlinear inside the * anon VMA -- PageKSM() is lost on actual swapout. */ - page = ksm_might_need_to_copy(page, vma, vmf->address); - if (unlikely(!page)) { + folio = ksm_might_need_to_copy(folio, vma, vmf->address); + if (unlikely(!folio)) { ret = VM_FAULT_OOM; + folio = swapcache; goto out_page; - } else if (unlikely(PTR_ERR(page) == -EHWPOISON)) { + } else if (unlikely(folio == ERR_PTR(-EHWPOISON))) { ret = VM_FAULT_HWPOISON; + folio = swapcache; goto out_page; } - folio = page_folio(page); + if (folio != swapcache) + page = folio_page(folio, 0);
/* * If we want to map a page that's in the swapcache writable, we diff --git a/mm/swapfile.c b/mm/swapfile.c index 941a98e7ed395..a677c16c48f46 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1897,11 +1897,13 @@ static int unuse_pte(struct vm_area_struct *vma, pmd_t *pmd, int ret = 1;
swapcache = page; - page = ksm_might_need_to_copy(page, vma, addr); - if (unlikely(!page)) + folio = ksm_might_need_to_copy(folio, vma, addr); + if (unlikely(!folio)) return -ENOMEM; - else if (unlikely(PTR_ERR(page) == -EHWPOISON)) + else if (unlikely(folio == ERR_PTR(-EHWPOISON))) hwpoisoned = true; + else + page = folio_file_page(folio, swp_offset(entry));
pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); if (unlikely(!pte || !pte_same_as_swp(ptep_get(pte),