block: remove QUEUE_FLAG_DISCARD

Just use a non-zero max_discard_sectors as an indicator for discard
support, similar to what is done for write zeroes.

The only places where needs special attention

block: remove QUEUE_FLAG_DISCARD

Just use a non-zero max_discard_sectors as an indicator for discard
support, similar to what is done for write zeroes.

The only places where needs special attention is the RAID5 driver,
which must clear discard support for security reasons by default,
even if the default stacking rules would allow for it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> [drbd]
Acked-by: Jan Höppner <hoeppner@linux.ibm.com> [s390]
Acked-by: Coly Li <colyli@suse.de> [bcache]
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-25-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

show more ...

f2fs: replace congestion_wait() calls with io_schedule_timeout()

As congestion is no longer tracked, congestion_wait() is effectively
equivalent to io_schedule_timeout().

So introduce f2fs_io_sched

f2fs: replace congestion_wait() calls with io_schedule_timeout()

As congestion is no longer tracked, congestion_wait() is effectively
equivalent to io_schedule_timeout().

So introduce f2fs_io_schedule_timeout() which sets TASK_UNINTERRUPTIBLE
and call that instead.

Link: https://lkml.kernel.org/r/164549983744.9187.6425865370954230902.stgit@noble.brown
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: Anna Schumaker <Anna.Schumaker@Netapp.com>
Cc: Chao Yu <chao@kernel.org>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Lars Ellenberg <lars.ellenberg@linbit.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Paolo Valente <paolo.valente@linaro.org>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

f2fs: introduce gc_urgent_mid mode

We need a mid level of gc urgent mode to do GC forcibly in a period
of given gc_urgent_sleep_time, but not like using greedy GC approach
and switching to SSR mode

f2fs: introduce gc_urgent_mid mode

We need a mid level of gc urgent mode to do GC forcibly in a period
of given gc_urgent_sleep_time, but not like using greedy GC approach
and switching to SSR mode such as gc urgent high mode. This can be
used for more aggressive periodic storage clean up.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

show more ...

f2fs: Convert f2fs_set_data_page_dirty to f2fs_dirty_data_folio

Removes several calls to __set_page_dirty_nobuffers(). Also turn the
PageSwapCache() case into a BUG() as there's no way for a swapca

f2fs: Convert f2fs_set_data_page_dirty to f2fs_dirty_data_folio

Removes several calls to __set_page_dirty_nobuffers(). Also turn the
PageSwapCache() case into a BUG() as there's no way for a swapcache page
to make it to a filesystem that doesn't use SWP_FS_OPS.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs
Tested-by: David Howells <dhowells@redhat.com> # afs

show more ...

f2fs: Convert invalidatepage to invalidate_folio

This is a minimal change which just accepts the new arguments and passes
the single struct page to the functions which do the work. There is
very li

f2fs: Convert invalidatepage to invalidate_folio

This is a minimal change which just accepts the new arguments and passes
the single struct page to the functions which do the work. There is
very little progress here toards making f2fs support large folios.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs
Tested-by: David Howells <dhowells@redhat.com> # afs

show more ...

f2fs: don't get FREEZE lock in f2fs_evict_inode in frozen fs

Let's purge inode cache in order to avoid the below deadlock.

[freeze test] shrinkder
freeze_super
- pwercpu_do

f2fs: don't get FREEZE lock in f2fs_evict_inode in frozen fs

Let's purge inode cache in order to avoid the below deadlock.

[freeze test] shrinkder
freeze_super
- pwercpu_down_write(SB_FREEZE_FS)
- super_cache_scan
- down_read(&sb->s_umount)
- prune_icache_sb
- dispose_list
- evict
- f2fs_evict_inode
thaw_super
- down_write(&sb->s_umount);
- __percpu_down_read(SB_FREEZE_FS)

Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

show more ...

f2fs: don't pass a bio to f2fs_target_device

Set the bdev at bio allocation time by changing the f2fs_target_device
calling conventions, so that no bio needs to be passed in.

Signed-off-by: Christo

f2fs: don't pass a bio to f2fs_target_device

Set the bdev at bio allocation time by changing the f2fs_target_device
calling conventions, so that no bio needs to be passed in.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20220228124123.856027-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

show more ...

f2fs: introduce F2FS_UNFAIR_RWSEM to support unfair rwsem

Unfair rwsem should be used when blk-cg is on. Otherwise, there is regression.

FYI, we noticed a -26.7% regression of aim7.jobs-per-min due

f2fs: introduce F2FS_UNFAIR_RWSEM to support unfair rwsem

Unfair rwsem should be used when blk-cg is on. Otherwise, there is regression.

FYI, we noticed a -26.7% regression of aim7.jobs-per-min due to commit:

commit: e4544b63a7ee49e7fbebf35ece0a6acd3b9617ae ("f2fs: move f2fs to use reader-unfair rwsems")
https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git master

in testcase: aim7
on test machine: 88 threads 2 sockets Intel(R) Xeon(R) Gold 6238M CPU @ 2.10GHz with 128G memory
with following parameters:

disk: 4BRD_12G
md: RAID0
fs: f2fs
test: sync_disk_rw
load: 100
cpufreq_governor: performance
ucode: 0x500320a

test-description: AIM7 is a traditional UNIX system level benchmark suite which is used to test and measure the performance of multiuser system.
test-url: https://sourceforge.net/projects/aimbench/files/aim-suite7/

Reported-by: kernel test robot <oliver.sang@intel.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

show more ...

f2fs: avoid an infinite loop in f2fs_sync_dirty_inodes

If one read IO is always failing, we can fall into an infinite loop in
f2fs_sync_dirty_inodes. This happens during xfstests/generic/475.

[ 14

f2fs: avoid an infinite loop in f2fs_sync_dirty_inodes

If one read IO is always failing, we can fall into an infinite loop in
f2fs_sync_dirty_inodes. This happens during xfstests/generic/475.

[ 142.803335] Buffer I/O error on dev dm-1, logical block 8388592, async page read
...
[ 382.887210] submit_bio_noacct+0xdd/0x2a0
[ 382.887213] submit_bio+0x80/0x110
[ 382.887223] __submit_bio+0x4d/0x300 [f2fs]
[ 382.887282] f2fs_submit_page_bio+0x125/0x200 [f2fs]
[ 382.887299] __get_meta_page+0xc9/0x280 [f2fs]
[ 382.887315] f2fs_get_meta_page+0x13/0x20 [f2fs]
[ 382.887331] f2fs_get_node_info+0x317/0x3c0 [f2fs]
[ 382.887350] f2fs_do_write_data_page+0x327/0x6f0 [f2fs]
[ 382.887367] f2fs_write_single_data_page+0x5b7/0x960 [f2fs]
[ 382.887386] f2fs_write_cache_pages+0x302/0x890 [f2fs]
[ 382.887405] ? preempt_count_add+0x7a/0xc0
[ 382.887408] f2fs_write_data_pages+0xfd/0x320 [f2fs]
[ 382.887425] ? _raw_spin_unlock+0x1a/0x30
[ 382.887428] do_writepages+0xd3/0x1d0
[ 382.887432] filemap_fdatawrite_wbc+0x69/0x90
[ 382.887434] filemap_fdatawrite+0x50/0x70
[ 382.887437] f2fs_sync_dirty_inodes+0xa4/0x270 [f2fs]
[ 382.887453] f2fs_write_checkpoint+0x189/0x1640 [f2fs]
[ 382.887469] ? schedule_timeout+0x114/0x150
[ 382.887471] ? ttwu_do_activate+0x6d/0xb0
[ 382.887473] ? preempt_count_add+0x7a/0xc0
[ 382.887476] kill_f2fs_super+0xca/0x100 [f2fs]
[ 382.887491] deactivate_locked_super+0x35/0xa0
[ 382.887494] deactivate_super+0x40/0x50
[ 382.887497] cleanup_mnt+0x139/0x190
[ 382.887499] __cleanup_mnt+0x12/0x20
[ 382.887501] task_work_run+0x64/0xa0
[ 382.887505] exit_to_user_mode_prepare+0x1b7/0x1c0
[ 382.887508] syscall_exit_to_user_mode+0x27/0x50
[ 382.887510] do_syscall_64+0x48/0xc0
[ 382.887513] entry_SYSCALL_64_after_hwframe+0x44/0xae

Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

show more ...

f2fs: Restore rwsem lockdep support

Lockdep uses lock class keys in its analysis. init_rwsem() instantiates
one lock class key with each init_rwsem() user as follows:

#define init_rwsem(sem)

f2fs: Restore rwsem lockdep support

Lockdep uses lock class keys in its analysis. init_rwsem() instantiates
one lock class key with each init_rwsem() user as follows:

#define init_rwsem(sem) \
do { \
static struct lock_class_key __key; \
\
__init_rwsem((sem), #sem, &__key); \
} while (0)

Commit e4544b63a7ee ("f2fs: move f2fs to use reader-unfair rwsems") reduced
the number of lock class keys from one per init_rwsem() user to one per
file in which init_f2fs_rwsem() is used. This causes the same lock class key
to be associated with multiple f2fs rwsems and also triggers a number of
false positive lockdep deadlock reports. Fix this by again instantiating one
lock class key with each init_f2fs_rwsem() caller.

Cc: Tim Murray <timmurray@google.com>
Reported-by: syzbot+0b9cadf5fc45a98a5083@syzkaller.appspotmail.com
Fixes: e4544b63a7ee ("f2fs: move f2fs to use reader-unfair rwsems")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

show more ...

f2fs: add a way to limit roll forward recovery time

This adds a sysfs entry to call checkpoint during fsync() in order to avoid
long elapsed time to run roll-forward recovery when booting the device

f2fs: add a way to limit roll forward recovery time

This adds a sysfs entry to call checkpoint during fsync() in order to avoid
long elapsed time to run roll-forward recovery when booting the device.
Default value doesn't enforce the limitation which is same as before.

Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

show more ...

f2fs: support direct I/O with fscrypt using blk-crypto

Encrypted files traditionally haven't supported DIO, due to the need to
encrypt/decrypt the data. However, when the encryption is implemented

f2fs: support direct I/O with fscrypt using blk-crypto

Encrypted files traditionally haven't supported DIO, due to the need to
encrypt/decrypt the data. However, when the encryption is implemented
using inline encryption (blk-crypto) instead of the traditional
filesystem-layer encryption, it is straightforward to support DIO.

Therefore, make f2fs support DIO on files that are using inline
encryption. Since f2fs uses iomap for DIO, and fscrypt support was
already added to iomap DIO, this just requires two small changes:

- Let DIO proceed when supported, by checking fscrypt_dio_supported()
instead of assuming that encrypted files never support DIO.

- In f2fs_iomap_begin(), use fscrypt_limit_io_blocks() to limit the
length of the mapping in the rare case where a DUN discontiguity
occurs in the middle of an extent. The iomap DIO implementation
requires this, since it assumes that it can submit a bio covering (up
to) the whole mapping, without checking fscrypt constraints itself.

Co-developed-by: Satya Tangirala <satyat@google.com>
Signed-off-by: Satya Tangirala <satyat@google.com>
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org>
Link: https://lore.kernel.org/r/20220128233940.79464-5-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>

show more ...

f2fs: introduce F2FS_IPU_HONOR_OPU_WRITE ipu policy

Once F2FS_IPU_FORCE policy is enabled in some cases:
a) f2fs forces to use F2FS_IPU_FORCE in a small-sized volume
b) user sets F2FS_IPU_FORCE poli

f2fs: introduce F2FS_IPU_HONOR_OPU_WRITE ipu policy

Once F2FS_IPU_FORCE policy is enabled in some cases:
a) f2fs forces to use F2FS_IPU_FORCE in a small-sized volume
b) user sets F2FS_IPU_FORCE policy via sysfs

Then we may fail to defragment file due to IPU policy check, it doesn't
make sense, let's introduce a new IPU policy to allow OPU during file
defragmentation.

In small-sized volume, let's enable F2FS_IPU_HONOR_OPU_WRITE policy
by default.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

show more ...

f2fs: adjust readahead block number during recovery

In a fragmented image, entries in dnode block list may locate in
incontiguous physical block address space, however, in recovery flow,
we will alw

f2fs: adjust readahead block number during recovery

In a fragmented image, entries in dnode block list may locate in
incontiguous physical block address space, however, in recovery flow,
we will always readahead BIO_MAX_VECS size blocks, so in such case,
current readahead policy is low efficient, let's adjust readahead
window size dynamically based on consecutiveness of dnode blocks.

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

show more ...

f2fs: move discard parameters into discard_cmd_control

This patch unifies parameters related to how often discard is issued and
how many requests go out at the same time by placing them in
discard_c

f2fs: move discard parameters into discard_cmd_control

This patch unifies parameters related to how often discard is issued and
how many requests go out at the same time by placing them in
discard_cmd_control. The move will allow the parameters to be modified
in the future without relying on hard-coded values.

Signed-off-by: Konstantin Vyshetsky <vkon@google.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

show more ...

f2fs: move f2fs to use reader-unfair rwsems

f2fs rw_semaphores work better if writers can starve readers,
especially for the checkpoint thread, because writers are strictly
more important than reade

f2fs: move f2fs to use reader-unfair rwsems

f2fs rw_semaphores work better if writers can starve readers,
especially for the checkpoint thread, because writers are strictly
more important than reader threads. This prevents significant priority
inversion between low-priority readers that blocked while trying to
acquire the read lock and a second acquisition of the write lock that
might be blocking high priority work.

Signed-off-by: Tim Murray <timmurray@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

show more ...

unicode: clean up the Kconfig symbol confusion

Turn the CONFIG_UNICODE symbol into a tristate that generates some always
built in code and remove the confusing CONFIG_UNICODE_UTF8_DATA symbol.

Note

unicode: clean up the Kconfig symbol confusion

Turn the CONFIG_UNICODE symbol into a tristate that generates some always
built in code and remove the confusing CONFIG_UNICODE_UTF8_DATA symbol.

Note that a lot of the IS_ENABLED() checks could be turned from cpp
statements into normal ifs, but this change is intended to be fairly
mechanic, so that should be cleaned up later.

Fixes: 2b3d04787012 ("unicode: Add utf8-data module")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>

show more ...

mm: Convert find_lock_entries() to use a folio_batch

find_lock_entries() already only returned the head page of folios, so
convert it to return a folio_batch instead of a pagevec. That cascades
thr

mm: Convert find_lock_entries() to use a folio_batch

find_lock_entries() already only returned the head page of folios, so
convert it to return a folio_batch instead of a pagevec. That cascades
through converting truncate_inode_pages_range() to
delete_from_page_cache_batch() and page_cache_delete_batch().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>

show more ...

f2fs: fix to reserve space for IO align feature

https://bugzilla.kernel.org/show_bug.cgi?id=204137

With below script, we will hit panic during new segment allocation:

DISK=bingo.img
MOUNT_DIR=/mnt

f2fs: fix to reserve space for IO align feature

https://bugzilla.kernel.org/show_bug.cgi?id=204137

With below script, we will hit panic during new segment allocation:

DISK=bingo.img
MOUNT_DIR=/mnt/f2fs

dd if=/dev/zero of=$DISK bs=1M count=105
mkfs.f2fe -a 1 -o 19 -t 1 -z 1 -f -q $DISK

mount -t f2fs $DISK $MOUNT_DIR -o "noinline_dentry,flush_merge,noextent_cache,mode=lfs,io_bits=7,fsync_mode=strict"

for (( i = 0; i < 4096; i++ )); do
name=`head /dev/urandom | tr -dc A-Za-z0-9 | head -c 10`
mkdir $MOUNT_DIR/$name
done

umount $MOUNT_DIR
rm $DISK

--- Core dump ---
Call Trace:
allocate_segment_by_default+0x9d/0x100 [f2fs]
f2fs_allocate_data_block+0x3c0/0x5c0 [f2fs]
do_write_page+0x62/0x110 [f2fs]
f2fs_outplace_write_data+0x43/0xc0 [f2fs]
f2fs_do_write_data_page+0x386/0x560 [f2fs]
__write_data_page+0x706/0x850 [f2fs]
f2fs_write_cache_pages+0x267/0x6a0 [f2fs]
f2fs_write_data_pages+0x19c/0x2e0 [f2fs]
do_writepages+0x1c/0x70
__filemap_fdatawrite_range+0xaa/0xe0
filemap_fdatawrite+0x1f/0x30
f2fs_sync_dirty_inodes+0x74/0x1f0 [f2fs]
block_operations+0xdc/0x350 [f2fs]
f2fs_write_checkpoint+0x104/0x1150 [f2fs]
f2fs_sync_fs+0xa2/0x120 [f2fs]
f2fs_balance_fs_bg+0x33c/0x390 [f2fs]
f2fs_write_node_pages+0x4c/0x1f0 [f2fs]
do_writepages+0x1c/0x70
__writeback_single_inode+0x45/0x320
writeback_sb_inodes+0x273/0x5c0
wb_writeback+0xff/0x2e0
wb_workfn+0xa1/0x370
process_one_work+0x138/0x350
worker_thread+0x4d/0x3d0
kthread+0x109/0x140
ret_from_fork+0x25/0x30

The root cause here is, with IO alignment feature enables, in worst
case, we need F2FS_IO_SIZE() free blocks space for single one 4k write
due to IO alignment feature will fill dummy pages to make IO being
aligned.

So we will easily run out of free segments during non-inline directory's
data writeback, even in process of foreground GC.

In order to fix this issue, I just propose to reserve additional free
space for IO alignment feature to handle worst case of free space usage
ratio during FGGC.

Fixes: 0a595ebaaa6b ("f2fs: support IO alignment for DATA and NODE writes")
Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

show more ...

f2fs: support fault injection to f2fs_trylock_op()

f2fs: support fault injection for f2fs_trylock_op()

This patch supports to inject fault into f2fs_trylock_op().

Usage:
a) echo 65536 > /sys/fs/f2

f2fs: support fault injection to f2fs_trylock_op()

f2fs: support fault injection for f2fs_trylock_op()

This patch supports to inject fault into f2fs_trylock_op().

Usage:
a) echo 65536 > /sys/fs/f2fs/<dev>/inject_type or
b) mount -o fault_type=65536 <dev> <mountpoint>

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

show more ...

f2fs: do not bother checkpoint by f2fs_get_node_info

This patch tries to mitigate lock contention between f2fs_write_checkpoint and
f2fs_get_node_info along with nat_tree_lock.

The idea is, if chec

f2fs: do not bother checkpoint by f2fs_get_node_info

This patch tries to mitigate lock contention between f2fs_write_checkpoint and
f2fs_get_node_info along with nat_tree_lock.

The idea is, if checkpoint is currently running, other threads that try to grab
nat_tree_lock would be better to wait for checkpoint.

Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

show more ...

f2fs: add gc_urgent_high_remaining sysfs node

Added a new sysfs node called gc_urgent_high_remaining. The user can
set the trial count limit for GC urgent high mode with this value. If
GC thread get

f2fs: add gc_urgent_high_remaining sysfs node

Added a new sysfs node called gc_urgent_high_remaining. The user can
set the trial count limit for GC urgent high mode with this value. If
GC thread gets to the limit, the mode will turn back to GC normal mode.
By default, the value is zero, which means there is no limit like before.

Signed-off-by: Daeho Jeong <daehojeong@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

show more ...

f2fs: avoid duplicate call of mark_inode_dirty

Let's check the condition first before set|clear bit.

Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

f2fs: use iomap for direct I/O

Make f2fs_file_read_iter() and f2fs_file_write_iter() use the iomap
direct I/O implementation instead of the fs/direct-io.c one.

The iomap implementation is more effi

f2fs: use iomap for direct I/O

Make f2fs_file_read_iter() and f2fs_file_write_iter() use the iomap
direct I/O implementation instead of the fs/direct-io.c one.

The iomap implementation is more efficient, and it also avoids the need
to add new features and optimizations to the old implementation.

This new implementation also eliminates the need for f2fs to hook bio
submission and completion and to allocate memory per-bio. This is
because it's possible to correctly update f2fs's in-flight DIO counters
using __iomap_dio_rw() in combination with an implementation of
iomap_dio_ops::end_io() (as suggested by Christoph Hellwig).

When possible, this new implementation preserves existing f2fs behavior
such as the conditions for falling back to buffered I/O.

This patch has been tested with xfstests by running 'gce-xfstests -c
f2fs -g auto -X generic/017' with and without this patch; no regressions
were seen. (Some tests fail both before and after. generic/017 hangs
both before and after, so it had to be excluded.)

Signed-off-by: Eric Biggers <ebiggers@google.com>
[Jaegeuk Kim: use spin_lock_bh for f2fs_update_iostat in softirq]
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

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f2fs: implement iomap operations

Implement 'struct iomap_ops' for f2fs, in preparation for making f2fs
use iomap for direct I/O.

Note that this may be used for other things besides direct I/O in th

f2fs: implement iomap operations

Implement 'struct iomap_ops' for f2fs, in preparation for making f2fs
use iomap for direct I/O.

Note that this may be used for other things besides direct I/O in the
future; however, for now I've only tested it for direct I/O.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

show more ...