The patch titled
Subject: buffer: convert __block_commit_write() to take a folio
has been added to the -mm mm-unstable branch. Its filename is
buffer-convert-__block_commit_write-to-take-a-folio.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/buffer-convert-__block_commit_write-to-take-a-folio.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@xxxxxxxxxxxxx>
Subject: buffer: convert __block_commit_write() to take a folio
Date: Mon, 12 Jun 2023 22:01:35 +0100
This removes a hidden call to compound_head() inside
__block_commit_write() and moves it to those callers which are still page
based. Also make block_write_end() safe for large folios.
Link: https://lkml.kernel.org/r/20230612210141.730128-9-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
Cc: Bob Peterson <rpeterso@xxxxxxxxxx>
Cc: Hannes Reinecke <hare@xxxxxxxx>
Cc: Luis Chamberlain <mcgrof@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/buffer.c | 38 +++++++++++++++++++-------------------
1 file changed, 19 insertions(+), 19 deletions(-)
--- a/fs/buffer.c~buffer-convert-__block_commit_write-to-take-a-folio
+++ a/fs/buffer.c
@@ -2116,15 +2116,15 @@ int __block_write_begin(struct page *pag
}
EXPORT_SYMBOL(__block_write_begin);
-static int __block_commit_write(struct inode *inode, struct page *page,
- unsigned from, unsigned to)
+static int __block_commit_write(struct inode *inode, struct folio *folio,
+ size_t from, size_t to)
{
- unsigned block_start, block_end;
- int partial = 0;
+ size_t block_start, block_end;
+ bool partial = false;
unsigned blocksize;
struct buffer_head *bh, *head;
- bh = head = page_buffers(page);
+ bh = head = folio_buffers(folio);
blocksize = bh->b_size;
block_start = 0;
@@ -2132,7 +2132,7 @@ static int __block_commit_write(struct i
block_end = block_start + blocksize;
if (block_end <= from || block_start >= to) {
if (!buffer_uptodate(bh))
- partial = 1;
+ partial = true;
} else {
set_buffer_uptodate(bh);
mark_buffer_dirty(bh);
@@ -2147,11 +2147,11 @@ static int __block_commit_write(struct i
/*
* If this is a partial write which happened to make all buffers
* uptodate then we can optimize away a bogus read_folio() for
- * the next read(). Here we 'discover' whether the page went
+ * the next read(). Here we 'discover' whether the folio went
* uptodate as a result of this (potentially partial) write.
*/
if (!partial)
- SetPageUptodate(page);
+ folio_mark_uptodate(folio);
return 0;
}
@@ -2188,10 +2188,9 @@ int block_write_end(struct file *file, s
loff_t pos, unsigned len, unsigned copied,
struct page *page, void *fsdata)
{
+ struct folio *folio = page_folio(page);
struct inode *inode = mapping->host;
- unsigned start;
-
- start = pos & (PAGE_SIZE - 1);
+ size_t start = pos - folio_pos(folio);
if (unlikely(copied < len)) {
/*
@@ -2203,18 +2202,18 @@ int block_write_end(struct file *file, s
* read_folio might come in and destroy our partial write.
*
* Do the simplest thing, and just treat any short write to a
- * non uptodate page as a zero-length write, and force the
+ * non uptodate folio as a zero-length write, and force the
* caller to redo the whole thing.
*/
- if (!PageUptodate(page))
+ if (!folio_test_uptodate(folio))
copied = 0;
- page_zero_new_buffers(page, start+copied, start+len);
+ page_zero_new_buffers(&folio->page, start+copied, start+len);
}
- flush_dcache_page(page);
+ flush_dcache_folio(folio);
/* This could be a short (even 0-length) commit */
- __block_commit_write(inode, page, start, start+copied);
+ __block_commit_write(inode, folio, start, start + copied);
return copied;
}
@@ -2537,8 +2536,9 @@ EXPORT_SYMBOL(cont_write_begin);
int block_commit_write(struct page *page, unsigned from, unsigned to)
{
- struct inode *inode = page->mapping->host;
- __block_commit_write(inode,page,from,to);
+ struct folio *folio = page_folio(page);
+ struct inode *inode = folio->mapping->host;
+ __block_commit_write(inode, folio, from, to);
return 0;
}
EXPORT_SYMBOL(block_commit_write);
@@ -2586,7 +2586,7 @@ int block_page_mkwrite(struct vm_area_st
ret = __block_write_begin_int(folio, 0, end, get_block, NULL);
if (!ret)
- ret = block_commit_write(&folio->page, 0, end);
+ ret = __block_commit_write(inode, folio, 0, end);
if (unlikely(ret < 0))
goto out_unlock;
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
gfs2-use-a-folio-inside-gfs2_jdata_writepage.patch
gfs2-pass-a-folio-to-__gfs2_jdata_write_folio.patch
gfs2-convert-gfs2_write_jdata_page-to-gfs2_write_jdata_folio.patch
buffer-convert-__block_write_full_page-to-__block_write_full_folio.patch
gfs2-support-ludicrously-large-folios-in-gfs2_trans_add_databufs.patch
buffer-make-block_write_full_page-handle-large-folios-correctly.patch
buffer-convert-block_page_mkwrite-to-use-a-folio.patch
buffer-convert-__block_commit_write-to-take-a-folio.patch
buffer-convert-page_zero_new_buffers-to-folio_zero_new_buffers.patch
buffer-convert-grow_dev_page-to-use-a-folio.patch
buffer-convert-init_page_buffers-to-folio_init_buffers.patch
buffer-convert-link_dev_buffers-to-take-a-folio.patch
buffer-use-a-folio-in-__find_get_block_slow.patch
buffer-convert-block_truncate_page-to-use-a-folio.patch
