The quilt patch titled
Subject: mpage: convert __mpage_writepage() to use a folio more fully
has been removed from the -mm tree. Its filename was
mpage-convert-__mpage_writepage-to-use-a-folio-more-fully.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: mpage: convert __mpage_writepage() to use a folio more fully
Date: Thu, 26 Jan 2023 20:12:55 +0000
This is just a conversion to the folio API. While there are some nods
towards supporting multi-page folios in here, the blocks array is still
sized for one page's worth of blocks, and there are other assumptions such
as the blocks_per_page variable.
[willy@xxxxxxxxxxxxx: fix accidentally-triggering WARN_ON_ONCE]
Link: https://lkml.kernel.org/r/Y9kuaBgXf9lKJ8b0@xxxxxxxxxxxxxxxxxxxx
Link: https://lkml.kernel.org/r/20230126201255.1681189-3-willy@xxxxxxxxxxxxx
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>
Cc: Jan Kara <jack@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
--- a/fs/mpage.c~mpage-convert-__mpage_writepage-to-use-a-folio-more-fully
+++ a/fs/mpage.c
@@ -443,13 +443,11 @@ void clean_page_buffers(struct page *pag
static int __mpage_writepage(struct folio *folio, struct writeback_control *wbc,
void *data)
{
- struct page *page = &folio->page;
struct mpage_data *mpd = data;
struct bio *bio = mpd->bio;
- struct address_space *mapping = page->mapping;
- struct inode *inode = page->mapping->host;
+ struct address_space *mapping = folio->mapping;
+ struct inode *inode = mapping->host;
const unsigned blkbits = inode->i_blkbits;
- unsigned long end_index;
const unsigned blocks_per_page = PAGE_SIZE >> blkbits;
sector_t last_block;
sector_t block_in_file;
@@ -460,13 +458,13 @@ static int __mpage_writepage(struct foli
int boundary = 0;
sector_t boundary_block = 0;
struct block_device *boundary_bdev = NULL;
- int length;
+ size_t length;
struct buffer_head map_bh;
loff_t i_size = i_size_read(inode);
int ret = 0;
+ struct buffer_head *head = folio_buffers(folio);
- if (page_has_buffers(page)) {
- struct buffer_head *head = page_buffers(page);
+ if (head) {
struct buffer_head *bh = head;
/* If they're all mapped and dirty, do it */
@@ -518,8 +516,8 @@ static int __mpage_writepage(struct foli
/*
* The page has no buffers: map it to disk
*/
- BUG_ON(!PageUptodate(page));
- block_in_file = (sector_t)page->index << (PAGE_SHIFT - blkbits);
+ BUG_ON(!folio_test_uptodate(folio));
+ block_in_file = (sector_t)folio->index << (PAGE_SHIFT - blkbits);
/*
* Whole page beyond EOF? Skip allocating blocks to avoid leaking
* space.
@@ -527,7 +525,7 @@ static int __mpage_writepage(struct foli
if (block_in_file >= (i_size + (1 << blkbits) - 1) >> blkbits)
goto page_is_mapped;
last_block = (i_size - 1) >> blkbits;
- map_bh.b_page = page;
+ map_bh.b_folio = folio;
for (page_block = 0; page_block < blocks_per_page; ) {
map_bh.b_state = 0;
@@ -556,8 +554,11 @@ static int __mpage_writepage(struct foli
first_unmapped = page_block;
page_is_mapped:
- end_index = i_size >> PAGE_SHIFT;
- if (page->index >= end_index) {
+ /* Don't bother writing beyond EOF, truncate will discard the folio */
+ if (folio_pos(folio) >= i_size)
+ goto confused;
+ length = folio_size(folio);
+ if (folio_pos(folio) + length > i_size) {
/*
* The page straddles i_size. It must be zeroed out on each
* and every writepage invocation because it may be mmapped.
@@ -566,11 +567,8 @@ page_is_mapped:
* is zeroed when mapped, and writes to that region are not
* written out to the file."
*/
- unsigned offset = i_size & (PAGE_SIZE - 1);
-
- if (page->index > end_index || !offset)
- goto confused;
- zero_user_segment(page, offset, PAGE_SIZE);
+ length = i_size - folio_pos(folio);
+ folio_zero_segment(folio, length, folio_size(folio));
}
/*
@@ -593,18 +591,18 @@ alloc_new:
* the confused fail path above (OOM) will be very confused when
* it finds all bh marked clean (i.e. it will not write anything)
*/
- wbc_account_cgroup_owner(wbc, page, PAGE_SIZE);
+ wbc_account_cgroup_owner(wbc, &folio->page, folio_size(folio));
length = first_unmapped << blkbits;
- if (bio_add_page(bio, page, length, 0) < length) {
+ if (!bio_add_folio(bio, folio, length, 0)) {
bio = mpage_bio_submit(bio);
goto alloc_new;
}
- clean_buffers(page, first_unmapped);
+ clean_buffers(&folio->page, first_unmapped);
- BUG_ON(PageWriteback(page));
- set_page_writeback(page);
- unlock_page(page);
+ BUG_ON(folio_test_writeback(folio));
+ folio_start_writeback(folio);
+ folio_unlock(folio);
if (boundary || (first_unmapped != blocks_per_page)) {
bio = mpage_bio_submit(bio);
if (boundary_block) {
@@ -623,7 +621,7 @@ confused:
/*
* The caller has a ref on the inode, so *mapping is stable
*/
- ret = block_write_full_page(page, mpd->get_block, wbc);
+ ret = block_write_full_page(&folio->page, mpd->get_block, wbc);
mapping_set_error(mapping, ret);
out:
mpd->bio = bio;
_
Patches currently in -mm which might be from willy@xxxxxxxxxxxxx are
