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mm: do not ignore mapping_gfp_mask in page cache allocation paths 

page_cache_read, do_generic_file_read, __generic_file_splice_read and
__ntfs_grab_cache_pages currently ignore mapping_gfp_mask when calling
add_to_page_cache_lru which might cause recursion into fs down in the
direct reclaim path if the mapping really relies on GFP_NOFS semantic.

This doesn't seem to be the case now because page_cache_read (page fault
path) doesn't seem to suffer from the reclaim recursion issues and
do_generic_file_read and __generic_file_splice_read also shouldn't be
called under fs locks which would deadlock in the reclaim path.  Anyway it
is better to obey mapping gfp mask and prevent from later breakage.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Anton Altaparmakov <anton@tuxera.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Michal Hocko 2015-06-24 16:58:06 -07:00 committed by Linus Torvalds
parent 0f96ae2928
commit 6afdb859b7
3 changed files with 7 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
fs/ntfs/file.c
View File

@ -525,7 +525,8 @@ static inline int __ntfs_grab_cache_pages(struct address_space *mapping,
}
}
err = add_to_page_cache_lru(*cached_page, mapping,
index, GFP_KERNEL);
index,
GFP_KERNEL & mapping_gfp_mask(mapping));
if (unlikely(err)) {
if (err == -EEXIST)
continue;

2
fs/splice.c
View File

@ -359,7 +359,7 @@ __generic_file_splice_read(struct file *in, loff_t *ppos,
break;
error = add_to_page_cache_lru(page, mapping, index,
GFP_KERNEL);
GFP_KERNEL & mapping_gfp_mask(mapping));
if (unlikely(error)) {
page_cache_release(page);
if (error == -EEXIST)

7
mm/filemap.c
View File

@ -1664,8 +1664,8 @@ static ssize_t do_generic_file_read(struct file *filp, loff_t *ppos,
error = -ENOMEM;
goto out;
}
error = add_to_page_cache_lru(page, mapping,
index, GFP_KERNEL);
error = add_to_page_cache_lru(page, mapping, index,
GFP_KERNEL & mapping_gfp_mask(mapping));
if (error) {
page_cache_release(page);
if (error == -EEXIST) {
@ -1766,7 +1766,8 @@ static int page_cache_read(struct file *file, pgoff_t offset)
if (!page)
return -ENOMEM;
ret = add_to_page_cache_lru(page, mapping, offset, GFP_KERNEL);
ret = add_to_page_cache_lru(page, mapping, offset,
GFP_KERNEL & mapping_gfp_mask(mapping));
if (ret == 0)
ret = mapping->a_ops->readpage(file, page);
else if (ret == -EEXIST)