+ mm-make-mapping_evict_folio-the-preferred-way-to-evict-clean-folios.patch added to mm-hotfixes-unstable branch

+ mm-make-mapping_evict_folio-the-preferred-way-to-evict-clean-folios.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: mm: make mapping_evict_folio() the preferred way to evict clean folios
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     mm-make-mapping_evict_folio-the-preferred-way-to-evict-clean-folios.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-make-mapping_evict_folio-the-preferred-way-to-evict-clean-folios.patch

This patch will later appear in the mm-hotfixes-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Subject: mm: make mapping_evict_folio() the preferred way to evict clean folios
Date: Wed, 8 Nov 2023 18:28:04 +0000

Patch series "Fix fault handler's handling of poisoned tail pages".

Since introducing the ability to have large folios in the page cache, it's
been possible to have a hwpoisoned tail page returned from the fault
handler.  We handle this situation poorly; failing to remove the affected
page from use.

This isn't a minimal patch to fix it, it's a full conversion of all the
code surrounding it.


This patch (of 6):

invalidate_inode_page() does very little beyond calling
mapping_evict_folio().  Move the check for mapping being NULL into
mapping_evict_folio() and make it available to the rest of the MM for use
in the next few patches.

Link: https://lkml.kernel.org/r/20231108182809.602073-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20231108182809.602073-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/internal.h |    1 +
 mm/truncate.c |   33 ++++++++++++++++-----------------
 2 files changed, 17 insertions(+), 17 deletions(-)

--- a/mm/internal.h~mm-make-mapping_evict_folio-the-preferred-way-to-evict-clean-folios
+++ a/mm/internal.h
@@ -138,6 +138,7 @@ void filemap_free_folio(struct address_s
 int truncate_inode_folio(struct address_space *mapping, struct folio *folio);
 bool truncate_inode_partial_folio(struct folio *folio, loff_t start,
 		loff_t end);
+long mapping_evict_folio(struct address_space *mapping, struct folio *folio);
 long invalidate_inode_page(struct page *page);
 unsigned long mapping_try_invalidate(struct address_space *mapping,
 		pgoff_t start, pgoff_t end, unsigned long *nr_failed);
--- a/mm/truncate.c~mm-make-mapping_evict_folio-the-preferred-way-to-evict-clean-folios
+++ a/mm/truncate.c
@@ -266,9 +266,22 @@ int generic_error_remove_page(struct add
 }
 EXPORT_SYMBOL(generic_error_remove_page);
 
-static long mapping_evict_folio(struct address_space *mapping,
-		struct folio *folio)
+/**
+ * mapping_evict_folio() - Remove an unused folio from the page-cache.
+ * @mapping: The mapping this folio belongs to.
+ * @folio: The folio to remove.
+ *
+ * Safely remove one folio from the page cache.
+ * It only drops clean, unused folios.
+ *
+ * Context: Folio must be locked.
+ * Return: The number of pages successfully removed.
+ */
+long mapping_evict_folio(struct address_space *mapping, struct folio *folio)
 {
+	/* The page may have been truncated before it was locked */
+	if (!mapping)
+		return 0;
 	if (folio_test_dirty(folio) || folio_test_writeback(folio))
 		return 0;
 	/* The refcount will be elevated if any page in the folio is mapped */
@@ -281,25 +294,11 @@ static long mapping_evict_folio(struct a
 	return remove_mapping(mapping, folio);
 }
 
-/**
- * invalidate_inode_page() - Remove an unused page from the pagecache.
- * @page: The page to remove.
- *
- * Safely invalidate one page from its pagecache mapping.
- * It only drops clean, unused pages.
- *
- * Context: Page must be locked.
- * Return: The number of pages successfully removed.
- */
 long invalidate_inode_page(struct page *page)
 {
 	struct folio *folio = page_folio(page);
-	struct address_space *mapping = folio_mapping(folio);
 
-	/* The page may have been truncated before it was locked */
-	if (!mapping)
-		return 0;
-	return mapping_evict_folio(mapping, folio);
+	return mapping_evict_folio(folio_mapping(folio), folio);
 }
 
 /**
_

Patches currently in -mm which might be from willy@infradead.org are

mm-make-mapping_evict_folio-the-preferred-way-to-evict-clean-folios.patch
mm-convert-__do_fault-to-use-a-folio.patch
mm-use-mapping_evict_folio-in-truncate_error_page.patch
mm-convert-soft_offline_in_use_page-to-use-a-folio.patch
mm-convert-isolate_page-to-mf_isolate_folio.patch
mm-remove-invalidate_inode_page.patch