The patch titled
Subject: buffer: add folio_alloc_buffers() helper
has been added to the -mm mm-unstable branch. Its filename is
buffer-add-folio_alloc_buffers-helper.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/buffer-add-folio_alloc_buffers-helper.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: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
Subject: buffer: add folio_alloc_buffers() helper
Date: Mon, 17 Apr 2023 14:36:16 +0200
Folio version of alloc_page_buffers() helper. This is required to convert
create_page_buffers() to folio_create_buffers() later in the series.
alloc_page_buffers() has been modified to call folio_alloc_buffers() which
adds one call to compound_head() but folio_alloc_buffers() removes one
call to compound_head() compared to the existing alloc_page_buffers()
implementation.
Link: https://lkml.kernel.org/r/20230417123618.22094-3-p.raghav@xxxxxxxxxxx
Signed-off-by: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
Reviewed-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Reviewed-by: Hannes Reinecke <hare@xxxxxxx>
Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Christian Brauner <brauner@xxxxxxxxxx>
Cc: Luis Chamberlain <mcgrof@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/buffer.c | 23 +++++++++++++++--------
include/linux/buffer_head.h | 2 ++
2 files changed, 17 insertions(+), 8 deletions(-)
--- a/fs/buffer.c~buffer-add-folio_alloc_buffers-helper
+++ a/fs/buffer.c
@@ -843,7 +843,7 @@ int remove_inode_buffers(struct inode *i
}
/*
- * Create the appropriate buffers when given a page for data area and
+ * Create the appropriate buffers when given a folio for data area and
* the size of each buffer.. Use the bh->b_this_page linked list to
* follow the buffers created. Return NULL if unable to create more
* buffers.
@@ -851,8 +851,8 @@ int remove_inode_buffers(struct inode *i
* The retry flag is used to differentiate async IO (paging, swapping)
* which may not fail from ordinary buffer allocations.
*/
-struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size,
- bool retry)
+struct buffer_head *folio_alloc_buffers(struct folio *folio, unsigned long size,
+ bool retry)
{
struct buffer_head *bh, *head;
gfp_t gfp = GFP_NOFS | __GFP_ACCOUNT;
@@ -862,12 +862,12 @@ struct buffer_head *alloc_page_buffers(s
if (retry)
gfp |= __GFP_NOFAIL;
- /* The page lock pins the memcg */
- memcg = page_memcg(page);
+ /* The folio lock pins the memcg */
+ memcg = folio_memcg(folio);
old_memcg = set_active_memcg(memcg);
head = NULL;
- offset = PAGE_SIZE;
+ offset = folio_size(folio);
while ((offset -= size) >= 0) {
bh = alloc_buffer_head(gfp);
if (!bh)
@@ -879,8 +879,8 @@ struct buffer_head *alloc_page_buffers(s
bh->b_size = size;
- /* Link the buffer to its page */
- set_bh_page(bh, page, offset);
+ /* Link the buffer to its folio */
+ folio_set_bh(bh, folio, offset);
}
out:
set_active_memcg(old_memcg);
@@ -899,6 +899,13 @@ no_grow:
goto out;
}
+EXPORT_SYMBOL_GPL(folio_alloc_buffers);
+
+struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size,
+ bool retry)
+{
+ return folio_alloc_buffers(page_folio(page), size, retry);
+}
EXPORT_SYMBOL_GPL(alloc_page_buffers);
static inline void
--- a/include/linux/buffer_head.h~buffer-add-folio_alloc_buffers-helper
+++ a/include/linux/buffer_head.h
@@ -199,6 +199,8 @@ void set_bh_page(struct buffer_head *bh,
void folio_set_bh(struct buffer_head *bh, struct folio *folio,
unsigned long offset);
bool try_to_free_buffers(struct folio *);
+struct buffer_head *folio_alloc_buffers(struct folio *folio, unsigned long size,
+ bool retry);
struct buffer_head *alloc_page_buffers(struct page *page, unsigned long size,
bool retry);
void create_empty_buffers(struct page *, unsigned long,
_
Patches currently in -mm which might be from p.raghav@xxxxxxxxxxx are
orangefs-use-folios-in-orangefs_readahead.patch
mpage-split-submit_bio-and-bio-end_io-handler-for-reads-and-writes.patch
mpage-use-folios-in-bio-end_io-handler.patch
fs-buffer-add-folio_set_bh-helper.patch
buffer-add-folio_alloc_buffers-helper.patch
fs-buffer-add-folio_create_empty_buffers-helper.patch
fs-buffer-convert-create_page_buffers-to-folio_create_buffers.patch
