linux/fs
Tejun Heo b16b1deb55 writeback: make writeback_control track the inode being written back
Currently, for cgroup writeback, the IO submission paths directly
associate the bio's with the blkcg from inode_to_wb_blkcg_css();
however, it'd be necessary to keep more writeback context to implement
foreign inode writeback detection.  wbc (writeback_control) is the
natural fit for the extra context - it persists throughout the
writeback of each inode and is passed all the way down to IO
submission paths.

This patch adds wbc_attach_and_unlock_inode(), wbc_detach_inode(), and
wbc_attach_fdatawrite_inode() which are used to associate wbc with the
inode being written back.  IO submission paths now use wbc_init_bio()
instead of directly associating bio's with blkcg themselves.  This
leaves inode_to_wb_blkcg_css() w/o any user.  The function is removed.

wbc currently only tracks the associated wb (bdi_writeback).  Future
patches will add more for foreign inode detection.  The association is
established under i_lock which will be depended upon when migrating
foreign inodes to other wb's.

As currently, once established, inode to wb association never changes,
going through wbc when initializing bio's doesn't cause any behavior
changes.

v2: submit_blk_blkcg() now checks whether the wbc is associated with a
    wb before dereferencing it.  This can happen when pageout() is
    writing pages directly without going through the usual writeback
    path.  As pageout() path is single-threaded, we don't want it to
    be blocked behind a slow cgroup and ultimately want it to delegate
    actual writing to the usual writeback path.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:39:48 -06:00
..
9p Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
adfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
affs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
afs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
autofs4 VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
befs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
bfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
btrfs block: remove management of bi_remaining when restoring original bi_end_io 2015-05-22 08:58:55 -06:00
cachefiles VFS: fs/cachefiles: d_backing_inode() annotations 2015-04-15 15:06:59 -04:00
ceph Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
cifs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
coda VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
configfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
cramfs
debugfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
devpts VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
dlm
ecryptfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
efivarfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
efs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
exofs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
exportfs VFS: (Scripted) Convert S_ISLNK/DIR/REG(dentry->d_inode) to d_is_*(dentry) 2015-02-22 11:38:41 -05:00
ext2 ext2: enable cgroup writeback support 2015-06-02 08:38:04 -06:00
ext3 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
ext4 writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
f2fs writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
fat writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
freevxfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
fscache
fuse writeback: move backing_dev_info->bdi_stat[] into bdi_writeback 2015-06-02 08:33:34 -06:00
gfs2 writeback: move bandwidth related fields from backing_dev_info into bdi_writeback 2015-06-02 08:33:34 -06:00
hfs writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
hfsplus writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
hostfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
hpfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
hppfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
hugetlbfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
isofs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
jbd
jbd2
jffs2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
jfs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
kernfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
lockd nfsd: eliminate NFSD_DEBUG 2015-04-21 16:16:02 -04:00
logfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
minix VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
ncpfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
nfs writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
nfs_common
nfsd Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
nilfs2 block: remove BIO_EOPNOTSUPP 2015-05-19 09:17:03 -06:00
nls
notify fanotify: fix event filtering with FAN_ONDIR set 2015-03-12 18:46:08 -07:00
ntfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
ocfs2 writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
omfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
openpromfs
overlayfs ovl: upper fs should not be R/O 2015-03-18 10:29:48 +01:00
proc Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
pstore Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
qnx4
qnx6 VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
quota Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
ramfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
reiserfs writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
romfs make new_sync_{read,write}() static 2015-04-11 22:29:40 -04:00
squashfs VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
sysfs sysfs: Only accept read/write permissions for file attributes 2015-03-25 13:27:57 +01:00
sysv VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
tracefs tracing: Have mkdir and rmdir be part of tracefs 2015-02-03 12:48:43 -05:00
ubifs Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
udf Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-26 17:22:07 -07:00
ufs writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
xfs writeback: separate out include/linux/backing-dev-defs.h 2015-06-02 08:33:34 -06:00
aio.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2015-04-16 23:27:56 -04:00
anon_inodes.c
attr.c
bad_inode.c don't bother with most of the bad_file_ops methods 2015-02-20 04:03:58 -05:00
binfmt_aout.c
binfmt_elf_fdpic.c
binfmt_elf.c mm: fold arch_randomize_brk into ARCH_HAS_ELF_RANDOMIZE 2015-04-14 16:49:05 -07:00
binfmt_em86.c
binfmt_flat.c
binfmt_misc.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
binfmt_script.c
block_dev.c bdi: make inode_to_bdi() inline 2015-06-02 08:33:34 -06:00
buffer.c writeback: make writeback_control track the inode being written back 2015-06-02 08:39:48 -06:00
char_dev.c
compat_binfmt_elf.c
compat_ioctl.c Bluetooth: bnep: Add support for get bnep features via ioctl 2015-04-03 23:21:34 +02:00
compat.c
coredump.c coredump: accept any write method 2015-04-11 22:29:39 -04:00
dax.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
dcache.c VFS: Impose ordering on accesses of d_inode and d_flags 2015-04-15 15:05:28 -04:00
dcookies.c
direct-io.c direct-io: only inc/dec inode->i_dio_count for file systems 2015-04-24 15:45:28 -04:00
drop_caches.c vmscan: per memory cgroup slab shrinkers 2015-02-12 18:54:09 -08:00
eventfd.c eventfd: don't take the spinlock in eventfd_poll 2015-02-17 14:34:52 -08:00
eventpoll.c epoll: optimize setting task running after blocking 2015-02-13 21:21:40 -08:00
exec.c fs: take i_mutex during prepare_binprm for set[ug]id executables 2015-04-19 13:46:21 -07:00
fcntl.c
fhandle.c
file_table.c ->aio_read and ->aio_write removed 2015-04-11 22:29:43 -04:00
file.c mm: rcu-protected get_mm_exe_file() 2015-04-17 09:04:07 -04:00
filesystems.c
fs_pin.c fs_pin: Allow for the possibility that m_list or s_list go unused. 2015-04-09 11:39:55 -05:00
fs_struct.c
fs-writeback.c writeback: make writeback_control track the inode being written back 2015-06-02 08:39:48 -06:00
inode.c writeback: make backing_dev_info host cgroup-specific bdi_writebacks 2015-06-02 08:33:35 -06:00
internal.h trylock_super(): replacement for grab_super_passive() 2015-02-22 11:38:42 -05:00
ioctl.c fsioctl.c: make generic_block_fiemap() signal-tolerant 2015-02-10 14:30:30 -08:00
Kconfig f2fs: relocate Kconfig from misc filesystems 2015-04-10 15:08:35 -07:00
Kconfig.binfmt mm: split ET_DYN ASLR from mmap ASLR 2015-04-14 16:49:05 -07:00
libfs.c VFS: fs library helpers: d_inode() annotations 2015-04-15 15:06:58 -04:00
locks.c proc: show locks in /proc/pid/fdinfo/X 2015-04-17 09:04:12 -04:00
Makefile This adds the new tracefs file system. This has been in linux-next for 2015-04-14 10:22:29 -07:00
mbcache.c
mount.h switch the IO-triggering parts of umount to fs_pin 2015-01-25 23:17:29 -05:00
mpage.c writeback: make writeback_control track the inode being written back 2015-06-02 08:39:48 -06:00
namei.c RCU pathwalk breakage when running into a symlink overmounting something 2015-04-24 15:52:14 -04:00
namespace.c mnt: Update detach_mounts to leave mounts connected 2015-04-09 11:39:57 -05:00
no-block.c
nsfs.c VFS: assorted weird filesystems: d_inode() annotations 2015-04-15 15:06:58 -04:00
open.c xfs: update for 4.1-rc1 2015-04-24 07:08:41 -07:00
pipe.c VFS: assorted weird filesystems: d_inode() annotations 2015-04-15 15:06:58 -04:00
pnode.c mnt: Don't propagate unmounts to locked mounts 2015-04-02 20:34:20 -05:00
pnode.h mnt: Honor MNT_LOCKED when detaching mounts 2015-04-09 11:39:55 -05:00
posix_acl.c VFS: assorted d_backing_inode() annotations 2015-04-15 15:06:59 -04:00
proc_namespace.c vfs: add support for a lazytime mount option 2015-02-05 02:45:00 -05:00
read_write.c new_sync_write(): discard ->ki_pos unless the return value is positive 2015-04-11 22:29:46 -04:00
readdir.c
select.c all arches, signal: move restart_block to struct task_struct 2015-02-12 18:54:12 -08:00
seq_file.c bitmap, cpumask, nodemask: remove dedicated formatting functions 2015-02-13 21:21:39 -08:00
signalfd.c
splice.c dax: unify ext2/4_{dax,}_file_operations 2015-04-15 16:35:20 -07:00
stack.c
stat.c VFS: assorted d_backing_inode() annotations 2015-04-15 15:06:59 -04:00
statfs.c
super.c cleancache: remove limit on the number of cleancache enabled filesystems 2015-04-14 16:49:03 -07:00
sync.c vfs: add support for a lazytime mount option 2015-02-05 02:45:00 -05:00
timerfd.c
utimes.c
xattr.c