The quilt patch titled
Subject: buffer: make folio_create_empty_buffers() return a buffer_head
has been removed from the -mm tree. Its filename was
buffer-make-folio_create_empty_buffers-return-a-buffer_head.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Subject: buffer: make folio_create_empty_buffers() return a buffer_head
Date: Mon, 16 Oct 2023 21:10:49 +0100
Patch series "Finish the create_empty_buffers() transition", v2.
Pankaj recently added folio_create_empty_buffers() as the folio equivalent
to create_empty_buffers(). This patch set finishes the conversion by
first converting all remaining filesystems to call
folio_create_empty_buffers(), then renaming it back to
create_empty_buffers(). I took the opportunity to make a few
simplifications like making folio_create_empty_buffers() return the head
buffer and extracting get_nth_bh() from nilfs2.
A few of the patches in this series aren't directly related to
create_empty_buffers(), but I saw them while I was working on this and
thought they'd be easy enough to add to this series. Compile-tested only,
other than ext4.
This patch (of 26):
Almost all callers want to know the first BH that was allocated for this
folio. We already have that handy, so return it.
Link: https://lkml.kernel.org/r/20231016201114.1928083-1-willy@xxxxxxxxxxxxx
Link: https://lkml.kernel.org/r/20231016201114.1928083-3-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Reviewed-by: Pankaj Raghav <p.raghav@xxxxxxxxxxx>
Cc: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
Cc: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/buffer.c | 24 +++++++++++++-----------
include/linux/buffer_head.h | 4 ++--
2 files changed, 15 insertions(+), 13 deletions(-)
--- a/fs/buffer.c~buffer-make-folio_create_empty_buffers-return-a-buffer_head
+++ a/fs/buffer.c
@@ -1641,8 +1641,8 @@ EXPORT_SYMBOL(block_invalidate_folio);
* block_dirty_folio() via private_lock. try_to_free_buffers
* is already excluded via the folio lock.
*/
-void folio_create_empty_buffers(struct folio *folio, unsigned long blocksize,
- unsigned long b_state)
+struct buffer_head *folio_create_empty_buffers(struct folio *folio,
+ unsigned long blocksize, unsigned long b_state)
{
struct buffer_head *bh, *head, *tail;
gfp_t gfp = GFP_NOFS | __GFP_ACCOUNT | __GFP_NOFAIL;
@@ -1669,6 +1669,8 @@ void folio_create_empty_buffers(struct f
}
folio_attach_private(folio, head);
spin_unlock(&folio->mapping->private_lock);
+
+ return head;
}
EXPORT_SYMBOL(folio_create_empty_buffers);
@@ -1770,13 +1772,15 @@ static struct buffer_head *folio_create_
struct inode *inode,
unsigned int b_state)
{
+ struct buffer_head *bh;
+
BUG_ON(!folio_test_locked(folio));
- if (!folio_buffers(folio))
- folio_create_empty_buffers(folio,
- 1 << READ_ONCE(inode->i_blkbits),
- b_state);
- return folio_buffers(folio);
+ bh = folio_buffers(folio);
+ if (!bh)
+ bh = folio_create_empty_buffers(folio,
+ 1 << READ_ONCE(inode->i_blkbits), b_state);
+ return bh;
}
/*
@@ -2676,10 +2680,8 @@ int block_truncate_page(struct address_s
return PTR_ERR(folio);
bh = folio_buffers(folio);
- if (!bh) {
- folio_create_empty_buffers(folio, blocksize, 0);
- bh = folio_buffers(folio);
- }
+ if (!bh)
+ bh = folio_create_empty_buffers(folio, blocksize, 0);
/* Find the buffer that contains "offset" */
offset = offset_in_folio(folio, from);
--- a/include/linux/buffer_head.h~buffer-make-folio_create_empty_buffers-return-a-buffer_head
+++ a/include/linux/buffer_head.h
@@ -203,8 +203,8 @@ struct buffer_head *alloc_page_buffers(s
bool retry);
void create_empty_buffers(struct page *, unsigned long,
unsigned long b_state);
-void folio_create_empty_buffers(struct folio *folio, unsigned long blocksize,
- unsigned long b_state);
+struct buffer_head *folio_create_empty_buffers(struct folio *folio,
+ unsigned long blocksize, unsigned long b_state);
void end_buffer_read_sync(struct buffer_head *bh, int uptodate);
void end_buffer_write_sync(struct buffer_head *bh, int uptodate);
void end_buffer_async_write(struct buffer_head *bh, int uptodate);
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
