+ shmem-add-shmem_read_folio-and-shmem_read_folio_gfp.patch added to mm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: shmem: add shmem_read_folio() and shmem_read_folio_gfp()
has been added to the -mm mm-unstable branch.  Its filename is
     shmem-add-shmem_read_folio-and-shmem_read_folio_gfp.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/shmem-add-shmem_read_folio-and-shmem_read_folio_gfp.patch

This patch will later appear in the mm-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: shmem: add shmem_read_folio() and shmem_read_folio_gfp()
Date: Mon, 6 Feb 2023 16:25:20 +0000

These are the folio replacements for shmem_read_mapping_page() and
shmem_read_mapping_page_gfp().

Link: https://lkml.kernel.org/r/20230206162520.4029022-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Mark Hemment <markhemm@googlemail.com>
Cc: Charan Teja Kalla <quic_charante@quicinc.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Pavankumar Kondeti <quic_pkondeti@quicinc.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---


--- a/include/linux/shmem_fs.h~shmem-add-shmem_read_folio-and-shmem_read_folio_gfp
+++ a/include/linux/shmem_fs.h
@@ -109,6 +109,14 @@ enum sgp_type {
 
 int shmem_get_folio(struct inode *inode, pgoff_t index, struct folio **foliop,
 		enum sgp_type sgp);
+struct folio *shmem_read_folio_gfp(struct address_space *mapping,
+		pgoff_t index, gfp_t gfp);
+
+static inline struct folio *shmem_read_folio(struct address_space *mapping,
+		pgoff_t index)
+{
+	return shmem_read_folio_gfp(mapping, index, mapping_gfp_mask(mapping));
+}
 
 static inline struct page *shmem_read_mapping_page(
 				struct address_space *mapping, pgoff_t index)
--- a/mm/shmem.c~shmem-add-shmem_read_folio-and-shmem_read_folio_gfp
+++ a/mm/shmem.c
@@ -4311,9 +4311,9 @@ int shmem_zero_setup(struct vm_area_stru
 }
 
 /**
- * shmem_read_mapping_page_gfp - read into page cache, using specified page allocation flags.
- * @mapping:	the page's address_space
- * @index:	the page index
+ * shmem_read_folio_gfp - read into page cache, using specified page allocation flags.
+ * @mapping:	the folio's address_space
+ * @index:	the folio index
  * @gfp:	the page allocator flags to use if allocating
  *
  * This behaves as a tmpfs "read_cache_page_gfp(mapping, index, gfp)",
@@ -4325,13 +4325,12 @@ int shmem_zero_setup(struct vm_area_stru
  * i915_gem_object_get_pages_gtt() mixes __GFP_NORETRY | __GFP_NOWARN in
  * with the mapping_gfp_mask(), to avoid OOMing the machine unnecessarily.
  */
-struct page *shmem_read_mapping_page_gfp(struct address_space *mapping,
-					 pgoff_t index, gfp_t gfp)
+struct folio *shmem_read_folio_gfp(struct address_space *mapping,
+		pgoff_t index, gfp_t gfp)
 {
 #ifdef CONFIG_SHMEM
 	struct inode *inode = mapping->host;
 	struct folio *folio;
-	struct page *page;
 	int error;
 
 	BUG_ON(!shmem_mapping(mapping));
@@ -4341,18 +4340,27 @@ struct page *shmem_read_mapping_page_gfp
 		return ERR_PTR(error);
 
 	folio_unlock(folio);
-	page = folio_file_page(folio, index);
+	return folio;
+#else
+	/*
+	 * The tiny !SHMEM case uses ramfs without swap
+	 */
+	return mapping_read_folio_gfp(mapping, index, gfp);
+#endif
+}
+EXPORT_SYMBOL_GPL(shmem_read_folio_gfp);
+
+struct page *shmem_read_mapping_page_gfp(struct address_space *mapping,
+					 pgoff_t index, gfp_t gfp)
+{
+	struct folio *folio = shmem_read_folio_gfp(mapping, index, gfp);
+	struct page *page = folio_file_page(folio, index);
+
 	if (PageHWPoison(page)) {
 		folio_put(folio);
 		return ERR_PTR(-EIO);
 	}
 
 	return page;
-#else
-	/*
-	 * The tiny !SHMEM case uses ramfs without swap
-	 */
-	return read_cache_page_gfp(mapping, index, gfp);
-#endif
 }
 EXPORT_SYMBOL_GPL(shmem_read_mapping_page_gfp);
_

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

mm-add-memcpy_from_file_folio.patch
filemap-add-mapping_read_folio_gfp.patch
shmem-add-shmem_read_folio-and-shmem_read_folio_gfp.patch
shmem-fix-w=1-build-warnings-with-config_shmem=n.patch