linux/fs/ext4
Michal Hocko 8a5c743e30 mm, memcg: use consistent gfp flags during readahead
Vladimir has noticed that we might declare memcg oom even during
readahead because read_pages only uses GFP_KERNEL (with mapping_gfp
restriction) while __do_page_cache_readahead uses
page_cache_alloc_readahead which adds __GFP_NORETRY to prevent from
OOMs.  This gfp mask discrepancy is really unfortunate and easily
fixable.  Drop page_cache_alloc_readahead() which only has one user and
outsource the gfp_mask logic into readahead_gfp_mask and propagate this
mask from __do_page_cache_readahead down to read_pages.

This alone would have only very limited impact as most filesystems are
implementing ->readpages and the common implementation mpage_readpages
does GFP_KERNEL (with mapping_gfp restriction) again.  We can tell it to
use readahead_gfp_mask instead as this function is called only during
readahead as well.  The same applies to read_cache_pages.

ext4 has its own ext4_mpage_readpages but the path which has pages !=
NULL can use the same gfp mask.  Btrfs, cifs, f2fs and orangefs are
doing a very similar pattern to mpage_readpages so the same can be
applied to them as well.

[akpm@linux-foundation.org: coding-style fixes]
[mhocko@suse.com: restrict gfp mask in mpage_alloc]
  Link: http://lkml.kernel.org/r/20160610074223.GC32285@dhcp22.suse.cz
Link: http://lkml.kernel.org/r/1465301556-26431-1-git-send-email-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Cc: Chris Mason <clm@fb.com>
Cc: Steve French <sfrench@samba.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Jan Kara <jack@suse.cz>
Cc: Mike Marshall <hubcap@omnibond.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Changman Lee <cm224.lee@samsung.com>
Cc: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-07-26 16:19:19 -07:00
..
acl.c posix_acl: Inode acl caching fixes 2016-03-31 00:30:15 -04:00
acl.h ext2/3/4: use generic posix ACL infrastructure 2014-01-25 23:58:19 -05:00
balloc.c ext4: fix race in transient ENOSPC detection 2016-05-13 00:42:40 -04:00
bitmap.c ext4: remove unused header files 2015-04-02 23:47:42 -04:00
block_validity.c ext4: call out CRC and corruption errors with specific error codes 2015-10-17 16:16:04 -04:00
crypto_fname.c ext4: Use skcipher 2016-01-27 20:35:55 +08:00
crypto_key.c ext4: Use skcipher 2016-01-27 20:35:55 +08:00
crypto_policy.c ext4 crypto: replace some BUG_ON()'s with error checks 2015-10-03 10:49:27 -04:00
crypto.c ext4/fscrypto: avoid RCU lookup in d_revalidate 2016-04-12 20:01:35 -07:00
dir.c Fix a number of bugs, most notably a potential stale data exposure 2016-05-24 12:55:26 -07:00
ext4_crypto.h ext4: Use skcipher 2016-01-27 20:35:55 +08:00
ext4_extents.h ext4: fix misspellings in comments. 2016-03-09 23:49:05 -05:00
ext4_jbd2.c ext4: fix potential use after free in __ext4_journal_stop 2015-10-17 22:57:06 -04:00
ext4_jbd2.h ext4: do not ask jbd2 to write data for delalloc buffers 2016-04-24 00:56:08 -04:00
ext4.h ext4: pre-zero allocated blocks for DAX IO 2016-05-13 00:51:15 -04:00
extents_status.c ext4: remove trailing \n from ext4_warning/ext4_error calls 2016-04-27 01:11:21 -04:00
extents_status.h ext4: move procfs registration code to fs/ext4/sysfs.c 2015-09-23 12:46:17 -04:00
extents.c ext4: remove unmeetable inconsisteny check from ext4_find_extent() 2016-05-05 22:43:04 -04:00
file.c dax: remote unused fault wrappers 2016-07-26 16:19:19 -07:00
fsync.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
hash.c ext4: remove unused header files 2015-04-02 23:47:42 -04:00
ialloc.c ext4: clean up error handling when orphan list is corrupted 2016-04-30 00:49:54 -04:00
indirect.c ext4: refactor direct IO code 2016-05-13 00:44:16 -04:00
inline.c ext4: remove trailing \n from ext4_warning/ext4_error calls 2016-04-27 01:11:21 -04:00
inode.c Fix a number of bugs, most notably a potential stale data exposure 2016-05-24 12:55:26 -07:00
ioctl.c Fix a number of bugs, most notably a potential stale data exposure 2016-05-24 12:55:26 -07:00
Kconfig ext4: Update EXT4_USE_FOR_EXT2 description 2015-09-24 13:27:47 +02:00
Makefile ext4: move sysfs code from super.c to fs/ext4/sysfs.c 2015-09-23 12:44:17 -04:00
mballoc.c ext4: silence UBSAN in ext4_mb_init() 2016-05-05 19:46:19 -04:00
mballoc.h ext4: fix compile error while opening the macro DOUBLE_CHECK 2016-03-13 17:18:12 -04:00
migrate.c ext4: fix misspellings in comments. 2016-03-09 23:49:05 -05:00
mmp.c ext4: remove trailing \n from ext4_warning/ext4_error calls 2016-04-27 01:11:21 -04:00
move_extent.c ext4: do not ask jbd2 to write data for delalloc buffers 2016-04-24 00:56:08 -04:00
namei.c Fix a number of bugs, most notably a potential stale data exposure 2016-05-24 12:55:26 -07:00
page-io.c ext4: remove unnecessary bio get/put 2016-05-05 22:09:49 -04:00
readpage.c mm, memcg: use consistent gfp flags during readahead 2016-07-26 16:19:19 -07:00
resize.c ext4: remove trailing \n from ext4_warning/ext4_error calls 2016-04-27 01:11:21 -04:00
super.c ext4: Add alignment check for DAX mount 2016-05-17 00:44:11 -06:00
symlink.c mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros 2016-04-04 10:41:08 -07:00
sysfs.c ext4: add "static" to ext4_seq_##name##_fops struct 2015-11-26 15:52:24 -05:00
truncate.h ext4: fix races between page faults and hole punching 2015-12-07 14:28:03 -05:00
xattr_security.c switch xattr_handler->set() to passing dentry and inode separately 2016-05-27 15:39:43 -04:00
xattr_trusted.c switch xattr_handler->set() to passing dentry and inode separately 2016-05-27 15:39:43 -04:00
xattr_user.c switch xattr_handler->set() to passing dentry and inode separately 2016-05-27 15:39:43 -04:00
xattr.c ext4: check if in-inode xattr is corrupted in ext4_expand_extra_isize_ea() 2016-03-22 16:13:15 -04:00
xattr.h mbcache2: rename to mbcache 2016-02-22 22:35:22 -05:00