buffer: convert __block_commit_write() to take a folio

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@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Bob Peterson <rpeterso@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Matthew Wilcox (Oracle) 2023-06-12 22:01:35 +01:00 committed by Andrew Morton
parent fe181377a2
commit 8c6cb3e3d5

View File

@ -2116,15 +2116,15 @@ int __block_write_begin(struct page *page, loff_t pos, unsigned len,
}
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 inode *inode, struct page *page,
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 inode *inode, struct page *page,
/*
* 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, struct address_space *mapping,
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, struct address_space *mapping,
* 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_struct *vma, struct vm_fault *vmf,
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;