Ext4 orphan inode handling is a bottleneck for workloads which heavily
truncate / unlink small files since it contends on the global
s_orphan_mutex lock (and generally it's difficult to improve scalability
of the ondisk linked list of orphaned inodes).
This patch implements new way of handling orphan inodes. Instead of
linking orphaned inode into a linked list, we store it's inode number in
a new special file which we call "orphan file". Only if there's no more
space in the orphan file (too many inodes are currently orphaned) we
fall back to using old style linked list. Currently we protect
operations in the orphan file with a spinlock for simplicity but even in
this setting we can substantially reduce the length of the critical
section and thus speedup some workloads. In the next patch we improve
this by making orphan handling lockless.
Note that the change is backwards compatible when the filesystem is
clean - the existence of the orphan file is a compat feature, we set
another ro-compat feature indicating orphan file needs scanning for
orphaned inodes when mounting filesystem read-write. This ro-compat
feature gets cleared on unmount / remount read-only.
Some performance data from 80 CPU Xeon Server with 512 GB of RAM,
filesystem located on SSD, average of 5 runs:
stress-orphan (microbenchmark truncating files byte-by-byte from N
processes in parallel)
Threads Time Time
Vanilla Patched
1 1.057200 0.945600
2 1.680400 1.331800
4 2.547000 1.995000
8 7.049400 6.424200
16 14.827800 14.937600
32 40.948200 33.038200
64 87.787400 60.823600
128 206.504000 122.941400
So we can see significant wins all over the board.
Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210816095713.16537-3-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Move functions for handling orphan inodes into a new file
fs/ext4/orphan.c to have them in one place and somewhat reduce size of
other files. No code changes.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210816095713.16537-2-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
JBD2 layer support triggers which are called when journaling layer moves
buffer to a certain state. We can use the frozen trigger, which gets
called when buffer data is frozen and about to be written out to the
journal, to compute block checksums for some buffer types (similarly as
does ocfs2). This avoids unnecessary repeated recomputation of the
checksum (at the cost of larger window where memory corruption won't be
caught by checksumming) and is even necessary when there are
unsynchronized updaters of the checksummed data.
So add superblock and journal trigger type arguments to
ext4_journal_get_write_access() and ext4_journal_get_create_access() so
that frozen triggers can be set accordingly. Also add inode argument to
ext4_walk_page_buffers() and all the callbacks used with that function
for the same purpose. This patch is mostly only a change of prototype of
the above mentioned functions and a few small helpers. Real checksumming
will come later.
Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210816095713.16537-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Commit 81414b4dd4 ("ext4: remove redundant sb checksum
recomputation") removed checksum recalculation after updating
superblock free space / inode counters in ext4_fill_super() based on
the fact that we will recalculate the checksum on superblock
writeout.
That is correct assumption but until the writeout happens (which can
take a long time) the checksum is incorrect in the buffer cache and if
programs such as tune2fs or resize2fs is called shortly after a file
system is mounted can fail. So return back the checksum recalculation
and add a comment explaining why.
Fixes: 81414b4dd4 ("ext4: remove redundant sb checksum recomputation")
Cc: stable@kernel.org
Reported-by: Boyang Xue <bxue@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/20210812124737.21981-1-jack@suse.cz
The function jbd2_journal_unregister_shrinker() was getting called
twice when the file system was getting unmounted. On Power and ARM
platforms this was causing kernel crash when unmounting the file
system, when a percpu_counter was destroyed twice.
Fix this by removing jbd2_journal_[un]register_shrinker() functions,
and inlining the shrinker setup and teardown into
journal_init_common() and jbd2_journal_destroy(). This means that
ext4 and ocfs2 now no longer need to know about registering and
unregistering jbd2's shrinker.
Also, while we're at it, rename the percpu counter from
j_jh_shrink_count to j_checkpoint_jh_count, since this makes it
clearer what this counter is intended to track.
Link: https://lore.kernel.org/r/20210705145025.3363130-1-tytso@mit.edu
Fixes: 4ba3fcdde7 ("jbd2,ext4: add a shrinker to release checkpointed buffers")
Reported-by: Jon Hunter <jonathanh@nvidia.com>
Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
After commit 618f003199 ("ext4: fix memory leak in
ext4_fill_super"), after the file system is remounted read-only, there
is a race where the kmmpd thread can exit, causing sbi->s_mmp_tsk to
point at freed memory, which the call to ext4_stop_mmpd() can trip
over.
Fix this by only allowing kmmpd() to exit when it is stopped via
ext4_stop_mmpd().
Link: https://lore.kernel.org/r/20210707002433.3719773-1-tytso@mit.edu
Reported-by: Ye Bin <yebin10@huawei.com>
Bug-Report-Link: <20210629143603.2166962-1-yebin10@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
If a writeback of the superblock fails with an I/O error, the buffer
is marked not uptodate. However, this can cause a WARN_ON to trigger
when we attempt to write superblock a second time. (Which might
succeed this time, for cerrtain types of block devices such as iSCSI
devices over a flaky network.)
Try to detect this case in flush_stashed_error_work(), and also change
__ext4_handle_dirty_metadata() so we always set the uptodate flag, not
just in the nojournal case.
Before this commit, this problem can be repliciated via:
1. dmsetup create dust1 --table '0 2097152 dust /dev/sdc 0 4096'
2. mount /dev/mapper/dust1 /home/test
3. dmsetup message dust1 0 addbadblock 0 10
4. cd /home/test
5. echo "XXXXXXX" > t
After a few seconds, we got following warning:
[ 80.654487] end_buffer_async_write: bh=0xffff88842f18bdd0
[ 80.656134] Buffer I/O error on dev dm-0, logical block 0, lost async page write
[ 85.774450] EXT4-fs error (device dm-0): ext4_check_bdev_write_error:193: comm kworker/u16:8: Error while async write back metadata
[ 91.415513] mark_buffer_dirty: bh=0xffff88842f18bdd0
[ 91.417038] ------------[ cut here ]------------
[ 91.418450] WARNING: CPU: 1 PID: 1944 at fs/buffer.c:1092 mark_buffer_dirty.cold+0x1c/0x5e
[ 91.440322] Call Trace:
[ 91.440652] __jbd2_journal_temp_unlink_buffer+0x135/0x220
[ 91.441354] __jbd2_journal_unfile_buffer+0x24/0x90
[ 91.441981] __jbd2_journal_refile_buffer+0x134/0x1d0
[ 91.442628] jbd2_journal_commit_transaction+0x249a/0x3240
[ 91.443336] ? put_prev_entity+0x2a/0x200
[ 91.443856] ? kjournald2+0x12e/0x510
[ 91.444324] kjournald2+0x12e/0x510
[ 91.444773] ? woken_wake_function+0x30/0x30
[ 91.445326] kthread+0x150/0x1b0
[ 91.445739] ? commit_timeout+0x20/0x20
[ 91.446258] ? kthread_flush_worker+0xb0/0xb0
[ 91.446818] ret_from_fork+0x1f/0x30
[ 91.447293] ---[ end trace 66f0b6bf3d1abade ]---
Signed-off-by: Ye Bin <yebin10@huawei.com>
Link: https://lore.kernel.org/r/20210615090537.3423231-1-yebin10@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
After s_error_count is incremented, signal the change in the
corresponding sysfs attribute via sysfs_notify. This allows userspace to
poll() on changes to /sys/fs/ext4/*/errors_count.
[ Moved call of ext4_notify_error_sysfs() to flush_stashed_error_work()
to avoid BUG's caused by calling sysfs_notify trying to sleep after
being called from an invalid context. -- TYT ]
Signed-off-by: Jonathan Davies <jonathan.davies@nutanix.com>
Link: https://lore.kernel.org/r/20210611140209.28903-1-jonathan.davies@nutanix.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
After we introduce a jbd2 shrinker to release checkpointed buffer's
journal head, we could free buffer without bdev_try_to_free_page()
under memory pressure. So this patch remove the whole
bdev_try_to_free_page() callback directly. It also remove many
use-after-free issues relate to it together.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210610112440.3438139-8-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Current metadata buffer release logic in bdev_try_to_free_page() have
a lot of use-after-free issues when umount filesystem concurrently, and
it is difficult to fix directly because ext4 is the only user of
s_op->bdev_try_to_free_page callback and we may have to add more special
refcount or lock that is only used by ext4 into the common vfs layer,
which is unacceptable.
One better solution is remove the bdev_try_to_free_page callback, but
the real problem is we cannot easily release journal_head on the
checkpointed buffer, so try_to_free_buffers() cannot release buffers and
page under memory pressure, which is more likely to trigger
out-of-memory. So we cannot remove the callback directly before we find
another way to release journal_head.
This patch introduce a shrinker to free journal_head on the checkpointed
transaction. After the journal_head got freed, try_to_free_buffers()
could free buffer properly.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210610112440.3438139-6-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Add a flags argument to jbd2_journal_flush to enable discarding or
zero-filling the journal blocks while flushing the journal.
Signed-off-by: Leah Rumancik <leah.rumancik@gmail.com>
Link: https://lore.kernel.org/r/20210518151327.130198-1-leah.rumancik@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
After commit c89128a008 ("ext4: handle errors on
ext4_commit_super"), 'ret' may be set to 0 before calling
ext4_fill_flex_info(), if ext4_fill_flex_info() fails ext4_mount()
doesn't return error code, it makes 'root' is null which causes crash
in legacy_get_tree().
Fixes: c89128a008 ("ext4: handle errors on ext4_commit_super")
Reported-by: Hulk Robot <hulkci@huawei.com>
Cc: <stable@vger.kernel.org> # v4.18+
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Link: https://lore.kernel.org/r/20210510111051.55650-1-yangyingliang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
In ext4_orphan_cleanup(), if ext4_truncate() failed to get a transaction
handle, it didn't remove the inode from the in-core orphan list, which
may probably trigger below error dump in ext4_destroy_inode() during the
final iput() and could lead to memory corruption on the later orphan
list changes.
EXT4-fs (sda): Inode 6291467 (00000000b8247c67): orphan list check failed!
00000000b8247c67: 0001f30a 00000004 00000000 00000023 ............#...
00000000e24cde71: 00000006 014082a3 00000000 00000000 ......@.........
0000000072c6a5ee: 00000000 00000000 00000000 00000000 ................
...
This patch fix this by cleanup in-core orphan list manually if
ext4_truncate() return error.
Cc: stable@kernel.org
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210507071904.160808-1-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
static int kthread(void *_create) will return -ENOMEM
or -EINTR in case of internal failure or
kthread_stop() call happens before threadfn call.
To prevent fancy error checking and make code
more straightforward we moved all cleanup code out
of kmmpd threadfn.
Also, dropped struct mmpd_data at all. Now struct super_block
is a threadfn data and struct buffer_head embedded into
struct ext4_sb_info.
Reported-by: syzbot+d9e482e303930fa4f6ff@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Link: https://lore.kernel.org/r/20210430185046.15742-1-paskripkin@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
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Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 fixes from Ted Ts'o:
"Miscellaneous ext4 bug fixes"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: Only advertise encrypted_casefold when encryption and unicode are enabled
ext4: fix no-key deletion for encrypt+casefold
ext4: fix memory leak in ext4_fill_super
ext4: fix fast commit alignment issues
ext4: fix bug on in ext4_es_cache_extent as ext4_split_extent_at failed
ext4: fix accessing uninit percpu counter variable with fast_commit
ext4: fix memory leak in ext4_mb_init_backend on error path.
Buffer head references must be released before calling kill_bdev();
otherwise the buffer head (and its page referenced by b_data) will not
be freed by kill_bdev, and subsequently that bh will be leaked.
If blocksizes differ, sb_set_blocksize() will kill current buffers and
page cache by using kill_bdev(). And then super block will be reread
again but using correct blocksize this time. sb_set_blocksize() didn't
fully free superblock page and buffer head, and being busy, they were
not freed and instead leaked.
This can easily be reproduced by calling an infinite loop of:
systemctl start <ext4_on_lvm>.mount, and
systemctl stop <ext4_on_lvm>.mount
... since systemd creates a cgroup for each slice which it mounts, and
the bh leak get amplified by a dying memory cgroup that also never
gets freed, and memory consumption is much more easily noticed.
Fixes: ce40733ce9 ("ext4: Check for return value from sb_set_blocksize")
Fixes: ac27a0ec11 ("ext4: initial copy of files from ext3")
Link: https://lore.kernel.org/r/20210521075533.95732-1-amakhalov@vmware.com
Signed-off-by: Alexey Makhalov <amakhalov@vmware.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
casefold, ensure that deleted file names are cleared in directory
blocks by zeroing directory entries when they are unlinked or moved as
part of a hash tree node split. We also improve the block allocator's
performance on a freshly mounted file system by prefetching block
bitmaps.
There are also the usual cleanups and bug fixes, including fixing a
page cache invalidation race when there is mixed buffered and direct
I/O and the block size is less than page size, and allow the dax flag
to be set and cleared on inline directories.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 updates from Ted Ts'o:
"New features for ext4 this cycle include support for encrypted
casefold, ensure that deleted file names are cleared in directory
blocks by zeroing directory entries when they are unlinked or moved as
part of a hash tree node split. We also improve the block allocator's
performance on a freshly mounted file system by prefetching block
bitmaps.
There are also the usual cleanups and bug fixes, including fixing a
page cache invalidation race when there is mixed buffered and direct
I/O and the block size is less than page size, and allow the dax flag
to be set and cleared on inline directories"
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (32 commits)
ext4: wipe ext4_dir_entry2 upon file deletion
ext4: Fix occasional generic/418 failure
fs: fix reporting supported extra file attributes for statx()
ext4: allow the dax flag to be set and cleared on inline directories
ext4: fix debug format string warning
ext4: fix trailing whitespace
ext4: fix various seppling typos
ext4: fix error return code in ext4_fc_perform_commit()
ext4: annotate data race in jbd2_journal_dirty_metadata()
ext4: annotate data race in start_this_handle()
ext4: fix ext4_error_err save negative errno into superblock
ext4: fix error code in ext4_commit_super
ext4: always panic when errors=panic is specified
ext4: delete redundant uptodate check for buffer
ext4: do not set SB_ACTIVE in ext4_orphan_cleanup()
ext4: make prefetch_block_bitmaps default
ext4: add proc files to monitor new structures
ext4: improve cr 0 / cr 1 group scanning
ext4: add MB_NUM_ORDERS macro
ext4: add mballoc stats proc file
...
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Merge tag 'fsnotify_for_v5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull fsnotify updates from Jan Kara:
- support for limited fanotify functionality for unpriviledged users
- faster merging of fanotify events
- a few smaller fsnotify improvements
* tag 'fsnotify_for_v5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
shmem: allow reporting fanotify events with file handles on tmpfs
fs: introduce a wrapper uuid_to_fsid()
fanotify_user: use upper_32_bits() to verify mask
fanotify: support limited functionality for unprivileged users
fanotify: configurable limits via sysfs
fanotify: limit number of event merge attempts
fsnotify: use hash table for faster events merge
fanotify: mix event info and pid into merge key hash
fanotify: reduce event objectid to 29-bit hash
fsnotify: allow fsnotify_{peek,remove}_first_event with empty queue
Some filesystem's use a digest of their uuid for f_fsid.
Create a simple wrapper for this open coded folding.
Filesystems that have a non null uuid but use the block device
number for f_fsid may also consider using this helper.
[JK: Added missing asm/byteorder.h include]
Link: https://lore.kernel.org/r/20210322173944.449469-2-amir73il@gmail.com
Acked-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Made suggested modifications from checkpatch in reference to ERROR:
trailing whitespace
Signed-off-by: Jack Qiu <jack.qiu@huawei.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20210409042035.15516-1-jack.qiu@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
We should set the error code when ext4_commit_super check argument failed.
Found in code review.
Fixes: c4be0c1dc4 ("filesystem freeze: add error handling of write_super_lockfs/unlockfs").
Cc: stable@kernel.org
Signed-off-by: Fengnan Chang <changfengnan@vivo.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/20210402101631.561-1-changfengnan@vivo.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Before commit 014c9caa29 ("ext4: make ext4_abort() use
__ext4_error()"), the following series of commands would trigger a
panic:
1. mount /dev/sda -o ro,errors=panic test
2. mount /dev/sda -o remount,abort test
After commit 014c9caa29, remounting a file system using the test
mount option "abort" will no longer trigger a panic. This commit will
restore the behaviour immediately before commit 014c9caa29.
(However, note that the Linux kernel's behavior has not been
consistent; some previous kernel versions, including 5.4 and 4.19
similarly did not panic after using the mount option "abort".)
This also makes a change to long-standing behaviour; namely, the
following series commands will now cause a panic, when previously it
did not:
1. mount /dev/sda -o ro,errors=panic test
2. echo test > /sys/fs/ext4/sda/trigger_fs_error
However, this makes ext4's behaviour much more consistent, so this is
a good thing.
Cc: stable@kernel.org
Fixes: 014c9caa29 ("ext4: make ext4_abort() use __ext4_error()")
Signed-off-by: Ye Bin <yebin10@huawei.com>
Link: https://lore.kernel.org/r/20210401081903.3421208-1-yebin10@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
When CONFIG_QUOTA is enabled, if we failed to mount the filesystem due
to some error happens behind ext4_orphan_cleanup(), it will end up
triggering a after free issue of super_block. The problem is that
ext4_orphan_cleanup() will set SB_ACTIVE flag if CONFIG_QUOTA is
enabled, after we cleanup the truncated inodes, the last iput() will put
them into the lru list, and these inodes' pages may probably dirty and
will be write back by the writeback thread, so it could be raced by
freeing super_block in the error path of mount_bdev().
After check the setting of SB_ACTIVE flag in ext4_orphan_cleanup(), it
was used to ensure updating the quota file properly, but evict inode and
trash data immediately in the last iput does not affect the quotafile,
so setting the SB_ACTIVE flag seems not required[1]. Fix this issue by
just remove the SB_ACTIVE setting.
[1] https://lore.kernel.org/linux-ext4/99cce8ca-e4a0-7301-840f-2ace67c551f3@huawei.com/T/#m04990cfbc4f44592421736b504afcc346b2a7c00
Cc: stable@kernel.org
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Tested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210331033138.918975-1-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Block bitmap prefetching is needed for these allocator optimization
data structures to get populated and provide better group scanning
order. So, turn it on bu default. prefetch_block_bitmaps mount option
is now marked as removed and a new option no_prefetch_block_bitmaps is
added to disable block bitmap prefetching.
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20210401172129.189766-8-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Instead of traversing through groups linearly, scan groups in specific
orders at cr 0 and cr 1. At cr 0, we want to find groups that have the
largest free order >= the order of the request. So, with this patch,
we maintain lists for each possible order and insert each group into a
list based on the largest free order in its buddy bitmap. During cr 0
allocation, we traverse these lists in the increasing order of largest
free orders. This allows us to find a group with the best available cr
0 match in constant time. If nothing can be found, we fallback to cr 1
immediately.
At CR1, the story is slightly different. We want to traverse in the
order of increasing average fragment size. For CR1, we maintain a rb
tree of groupinfos which is sorted by average fragment size. Instead
of traversing linearly, at CR1, we traverse in the order of increasing
average fragment size, starting at the most optimal group. This brings
down cr 1 search complexity to log(num groups).
For cr >= 2, we just perform the linear search as before. Also, in
case of lock contention, we intermittently fallback to linear search
even in CR 0 and CR 1 cases. This allows us to proceed during the
allocation path even in case of high contention.
There is an opportunity to do optimization at CR2 too. That's because
at CR2 we only consider groups where bb_free counter (number of free
blocks) is greater than the request extent size. That's left as future
work.
All the changes introduced in this patch are protected under a new
mount option "mb_optimize_scan".
With this patchset, following experiment was performed:
Created a highly fragmented disk of size 65TB. The disk had no
contiguous 2M regions. Following command was run consecutively for 3
times:
time dd if=/dev/urandom of=file bs=2M count=10
Here are the results with and without cr 0/1 optimizations introduced
in this patch:
|---------+------------------------------+---------------------------|
| | Without CR 0/1 Optimizations | With CR 0/1 Optimizations |
|---------+------------------------------+---------------------------|
| 1st run | 5m1.871s | 2m47.642s |
| 2nd run | 2m28.390s | 0m0.611s |
| 3rd run | 2m26.530s | 0m1.255s |
|---------+------------------------------+---------------------------|
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/20210401172129.189766-6-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Before this patch, the function parse_options() was returning
journal_devnum and journal_ioprio variables to the caller. This patch
generalizes that interface to allow parse_options to return any parsed
options to return back to the caller. In this patch series, it gets
used to capture the value of "mb_optimize_scan=%u" mount option.
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Reviewed-by: Ritesh Harjani <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/20210401172129.189766-3-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This adds support for encryption with casefolding.
Since the name on disk is case preserving, and also encrypted, we can no
longer just recompute the hash on the fly. Additionally, to avoid
leaking extra information from the hash of the unencrypted name, we use
siphash via an fscrypt v2 policy.
The hash is stored at the end of the directory entry for all entries
inside of an encrypted and casefolded directory apart from those that
deal with '.' and '..'. This way, the change is backwards compatible
with existing ext4 filesystems.
[ Changed to advertise this feature via the file:
/sys/fs/ext4/features/encrypted_casefold -- TYT ]
Signed-off-by: Daniel Rosenberg <drosen@google.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/20210319073414.1381041-2-drosen@google.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
When filesystem mount fails because of corrupted filesystem we first
cancel the s_err_report timer reminding fs errors every day and only
then we flush s_error_work. However s_error_work may report another fs
error and re-arm timer thus resulting in timer use-after-free. Fix the
problem by first flushing the work and only after that canceling the
s_err_report timer.
Reported-by: syzbot+628472a2aac693ab0fcd@syzkaller.appspotmail.com
Fixes: 2d01ddc866 ("ext4: save error info to sb through journal if available")
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210315165906.2175-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
When generic/371 is run on kvm-xfstests using 5.10 and 5.11 kernels, it
fails at significant rates on the two test scenarios that disable
delayed allocation (ext3conv and data_journal) and force actual block
allocation for the fallocate and pwrite functions in the test. The
failure rate on 5.10 for both ext3conv and data_journal on one test
system typically runs about 85%. On 5.11, the failure rate on ext3conv
sometimes drops to as low as 1% while the rate on data_journal
increases to nearly 100%.
The observed failures are largely due to ext4_should_retry_alloc()
cutting off block allocation retries when s_mb_free_pending (used to
indicate that a transaction in progress will free blocks) is 0.
However, free space is usually available when this occurs during runs
of generic/371. It appears that a thread attempting to allocate
blocks is just missing transaction commits in other threads that
increase the free cluster count and reset s_mb_free_pending while
the allocating thread isn't running. Explicitly testing for free space
availability avoids this race.
The current code uses a post-increment operator in the conditional
expression that determines whether the retry limit has been exceeded.
This means that the conditional expression uses the value of the
retry counter before it's increased, resulting in an extra retry cycle.
The current code actually retries twice before hitting its retry limit
rather than once.
Increasing the retry limit to 3 from the current actual maximum retry
count of 2 in combination with the change described above reduces the
observed failure rate to less that 0.1% on both ext3conv and
data_journal with what should be limited impact on users sensitive to
the overhead caused by retries.
A per filesystem percpu counter exported via sysfs is added to allow
users or developers to track the number of times the retry limit is
exceeded without resorting to debugging methods. This should provide
some insight into worst case retry behavior.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Link: https://lore.kernel.org/r/20210218151132.19678-1-enwlinux@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
cycle...
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 updates from Ted Ts'o:
"Miscellaneous ext4 cleanups and bug fixes. Pretty boring this cycle..."
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: add .kunitconfig fragment to enable ext4-specific tests
ext: EXT4_KUNIT_TESTS should depend on EXT4_FS instead of selecting it
ext4: reset retry counter when ext4_alloc_file_blocks() makes progress
ext4: fix potential htree index checksum corruption
ext4: factor out htree rep invariant check
ext4: Change list_for_each* to list_for_each_entry*
ext4: don't try to processed freed blocks until mballoc is initialized
ext4: use DEFINE_MUTEX() for mutex lock
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Merge tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull idmapped mounts from Christian Brauner:
"This introduces idmapped mounts which has been in the making for some
time. Simply put, different mounts can expose the same file or
directory with different ownership. This initial implementation comes
with ports for fat, ext4 and with Christoph's port for xfs with more
filesystems being actively worked on by independent people and
maintainers.
Idmapping mounts handle a wide range of long standing use-cases. Here
are just a few:
- Idmapped mounts make it possible to easily share files between
multiple users or multiple machines especially in complex
scenarios. For example, idmapped mounts will be used in the
implementation of portable home directories in
systemd-homed.service(8) where they allow users to move their home
directory to an external storage device and use it on multiple
computers where they are assigned different uids and gids. This
effectively makes it possible to assign random uids and gids at
login time.
- It is possible to share files from the host with unprivileged
containers without having to change ownership permanently through
chown(2).
- It is possible to idmap a container's rootfs and without having to
mangle every file. For example, Chromebooks use it to share the
user's Download folder with their unprivileged containers in their
Linux subsystem.
- It is possible to share files between containers with
non-overlapping idmappings.
- Filesystem that lack a proper concept of ownership such as fat can
use idmapped mounts to implement discretionary access (DAC)
permission checking.
- They allow users to efficiently changing ownership on a per-mount
basis without having to (recursively) chown(2) all files. In
contrast to chown (2) changing ownership of large sets of files is
instantenous with idmapped mounts. This is especially useful when
ownership of a whole root filesystem of a virtual machine or
container is changed. With idmapped mounts a single syscall
mount_setattr syscall will be sufficient to change the ownership of
all files.
- Idmapped mounts always take the current ownership into account as
idmappings specify what a given uid or gid is supposed to be mapped
to. This contrasts with the chown(2) syscall which cannot by itself
take the current ownership of the files it changes into account. It
simply changes the ownership to the specified uid and gid. This is
especially problematic when recursively chown(2)ing a large set of
files which is commong with the aforementioned portable home
directory and container and vm scenario.
- Idmapped mounts allow to change ownership locally, restricting it
to specific mounts, and temporarily as the ownership changes only
apply as long as the mount exists.
Several userspace projects have either already put up patches and
pull-requests for this feature or will do so should you decide to pull
this:
- systemd: In a wide variety of scenarios but especially right away
in their implementation of portable home directories.
https://systemd.io/HOME_DIRECTORY/
- container runtimes: containerd, runC, LXD:To share data between
host and unprivileged containers, unprivileged and privileged
containers, etc. The pull request for idmapped mounts support in
containerd, the default Kubernetes runtime is already up for quite
a while now: https://github.com/containerd/containerd/pull/4734
- The virtio-fs developers and several users have expressed interest
in using this feature with virtual machines once virtio-fs is
ported.
- ChromeOS: Sharing host-directories with unprivileged containers.
I've tightly synced with all those projects and all of those listed
here have also expressed their need/desire for this feature on the
mailing list. For more info on how people use this there's a bunch of
talks about this too. Here's just two recent ones:
https://www.cncf.io/wp-content/uploads/2020/12/Rootless-Containers-in-Gitpod.pdfhttps://fosdem.org/2021/schedule/event/containers_idmap/
This comes with an extensive xfstests suite covering both ext4 and
xfs:
https://git.kernel.org/brauner/xfstests-dev/h/idmapped_mounts
It covers truncation, creation, opening, xattrs, vfscaps, setid
execution, setgid inheritance and more both with idmapped and
non-idmapped mounts. It already helped to discover an unrelated xfs
setgid inheritance bug which has since been fixed in mainline. It will
be sent for inclusion with the xfstests project should you decide to
merge this.
In order to support per-mount idmappings vfsmounts are marked with
user namespaces. The idmapping of the user namespace will be used to
map the ids of vfs objects when they are accessed through that mount.
By default all vfsmounts are marked with the initial user namespace.
The initial user namespace is used to indicate that a mount is not
idmapped. All operations behave as before and this is verified in the
testsuite.
Based on prior discussions we want to attach the whole user namespace
and not just a dedicated idmapping struct. This allows us to reuse all
the helpers that already exist for dealing with idmappings instead of
introducing a whole new range of helpers. In addition, if we decide in
the future that we are confident enough to enable unprivileged users
to setup idmapped mounts the permission checking can take into account
whether the caller is privileged in the user namespace the mount is
currently marked with.
The user namespace the mount will be marked with can be specified by
passing a file descriptor refering to the user namespace as an
argument to the new mount_setattr() syscall together with the new
MOUNT_ATTR_IDMAP flag. The system call follows the openat2() pattern
of extensibility.
The following conditions must be met in order to create an idmapped
mount:
- The caller must currently have the CAP_SYS_ADMIN capability in the
user namespace the underlying filesystem has been mounted in.
- The underlying filesystem must support idmapped mounts.
- The mount must not already be idmapped. This also implies that the
idmapping of a mount cannot be altered once it has been idmapped.
- The mount must be a detached/anonymous mount, i.e. it must have
been created by calling open_tree() with the OPEN_TREE_CLONE flag
and it must not already have been visible in the filesystem.
The last two points guarantee easier semantics for userspace and the
kernel and make the implementation significantly simpler.
By default vfsmounts are marked with the initial user namespace and no
behavioral or performance changes are observed.
The manpage with a detailed description can be found here:
1d7b902e28
In order to support idmapped mounts, filesystems need to be changed
and mark themselves with the FS_ALLOW_IDMAP flag in fs_flags. The
patches to convert individual filesystem are not very large or
complicated overall as can be seen from the included fat, ext4, and
xfs ports. Patches for other filesystems are actively worked on and
will be sent out separately. The xfstestsuite can be used to verify
that port has been done correctly.
The mount_setattr() syscall is motivated independent of the idmapped
mounts patches and it's been around since July 2019. One of the most
valuable features of the new mount api is the ability to perform
mounts based on file descriptors only.
Together with the lookup restrictions available in the openat2()
RESOLVE_* flag namespace which we added in v5.6 this is the first time
we are close to hardened and race-free (e.g. symlinks) mounting and
path resolution.
While userspace has started porting to the new mount api to mount
proper filesystems and create new bind-mounts it is currently not
possible to change mount options of an already existing bind mount in
the new mount api since the mount_setattr() syscall is missing.
With the addition of the mount_setattr() syscall we remove this last
restriction and userspace can now fully port to the new mount api,
covering every use-case the old mount api could. We also add the
crucial ability to recursively change mount options for a whole mount
tree, both removing and adding mount options at the same time. This
syscall has been requested multiple times by various people and
projects.
There is a simple tool available at
https://github.com/brauner/mount-idmapped
that allows to create idmapped mounts so people can play with this
patch series. I'll add support for the regular mount binary should you
decide to pull this in the following weeks:
Here's an example to a simple idmapped mount of another user's home
directory:
u1001@f2-vm:/$ sudo ./mount --idmap both:1000:1001:1 /home/ubuntu/ /mnt
u1001@f2-vm:/$ ls -al /home/ubuntu/
total 28
drwxr-xr-x 2 ubuntu ubuntu 4096 Oct 28 22:07 .
drwxr-xr-x 4 root root 4096 Oct 28 04:00 ..
-rw------- 1 ubuntu ubuntu 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 ubuntu ubuntu 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 ubuntu ubuntu 807 Feb 25 2020 .profile
-rw-r--r-- 1 ubuntu ubuntu 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ ls -al /mnt/
total 28
drwxr-xr-x 2 u1001 u1001 4096 Oct 28 22:07 .
drwxr-xr-x 29 root root 4096 Oct 28 22:01 ..
-rw------- 1 u1001 u1001 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 u1001 u1001 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 u1001 u1001 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 u1001 u1001 807 Feb 25 2020 .profile
-rw-r--r-- 1 u1001 u1001 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 u1001 u1001 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ touch /mnt/my-file
u1001@f2-vm:/$ setfacl -m u:1001:rwx /mnt/my-file
u1001@f2-vm:/$ sudo setcap -n 1001 cap_net_raw+ep /mnt/my-file
u1001@f2-vm:/$ ls -al /mnt/my-file
-rw-rwxr--+ 1 u1001 u1001 0 Oct 28 22:14 /mnt/my-file
u1001@f2-vm:/$ ls -al /home/ubuntu/my-file
-rw-rwxr--+ 1 ubuntu ubuntu 0 Oct 28 22:14 /home/ubuntu/my-file
u1001@f2-vm:/$ getfacl /mnt/my-file
getfacl: Removing leading '/' from absolute path names
# file: mnt/my-file
# owner: u1001
# group: u1001
user::rw-
user:u1001:rwx
group::rw-
mask::rwx
other::r--
u1001@f2-vm:/$ getfacl /home/ubuntu/my-file
getfacl: Removing leading '/' from absolute path names
# file: home/ubuntu/my-file
# owner: ubuntu
# group: ubuntu
user::rw-
user:ubuntu:rwx
group::rw-
mask::rwx
other::r--"
* tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: (41 commits)
xfs: remove the possibly unused mp variable in xfs_file_compat_ioctl
xfs: support idmapped mounts
ext4: support idmapped mounts
fat: handle idmapped mounts
tests: add mount_setattr() selftests
fs: introduce MOUNT_ATTR_IDMAP
fs: add mount_setattr()
fs: add attr_flags_to_mnt_flags helper
fs: split out functions to hold writers
namespace: only take read lock in do_reconfigure_mnt()
mount: make {lock,unlock}_mount_hash() static
namespace: take lock_mount_hash() directly when changing flags
nfs: do not export idmapped mounts
overlayfs: do not mount on top of idmapped mounts
ecryptfs: do not mount on top of idmapped mounts
ima: handle idmapped mounts
apparmor: handle idmapped mounts
fs: make helpers idmap mount aware
exec: handle idmapped mounts
would_dump: handle idmapped mounts
...
If we try to make any changes via the journal between when the journal
is initialized, but before the multi-block allocated is initialized,
we will end up deferencing a NULL pointer when the journal commit
callback function calls ext4_process_freed_data().
The proximate cause of this failure was commit 2d01ddc866 ("ext4:
save error info to sb through journal if available") since file system
corruption problems detected before the call to ext4_mb_init() would
result in a journal commit before we aborted the mount of the file
system.... and we would then trigger the NULL pointer deref.
Link: https://lore.kernel.org/r/YAm8qH/0oo2ofSMR@mit.edu
Reported-by: Murphy Zhou <jencce.kernel@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
There is no point in allocating memory for a synchronous flush.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Enable idmapped mounts for ext4. All dedicated helpers we need for this
exist. So this basically just means we're passing down the
user_namespace argument from the VFS methods to the relevant helpers.
Let's create simple example where we idmap an ext4 filesystem:
root@f2-vm:~# truncate -s 5G ext4.img
root@f2-vm:~# mkfs.ext4 ./ext4.img
mke2fs 1.45.5 (07-Jan-2020)
Discarding device blocks: done
Creating filesystem with 1310720 4k blocks and 327680 inodes
Filesystem UUID: 3fd91794-c6ca-4b0f-9964-289a000919cf
Superblock backups stored on blocks:
32768, 98304, 163840, 229376, 294912, 819200, 884736
Allocating group tables: done
Writing inode tables: done
Creating journal (16384 blocks): done
Writing superblocks and filesystem accounting information: done
root@f2-vm:~# losetup -f --show ./ext4.img
/dev/loop0
root@f2-vm:~# mount /dev/loop0 /mnt
root@f2-vm:~# ls -al /mnt/
total 24
drwxr-xr-x 3 root root 4096 Oct 28 13:34 .
drwxr-xr-x 30 root root 4096 Oct 28 13:22 ..
drwx------ 2 root root 16384 Oct 28 13:34 lost+found
# Let's create an idmapped mount at /idmapped1 where we map uid and gid
# 0 to uid and gid 1000
root@f2-vm:/# ./mount-idmapped --map-mount b:0:1000:1 /mnt/ /idmapped1/
root@f2-vm:/# ls -al /idmapped1/
total 24
drwxr-xr-x 3 ubuntu ubuntu 4096 Oct 28 13:34 .
drwxr-xr-x 30 root root 4096 Oct 28 13:22 ..
drwx------ 2 ubuntu ubuntu 16384 Oct 28 13:34 lost+found
# Let's create an idmapped mount at /idmapped2 where we map uid and gid
# 0 to uid and gid 2000
root@f2-vm:/# ./mount-idmapped --map-mount b:0:2000:1 /mnt/ /idmapped2/
root@f2-vm:/# ls -al /idmapped2/
total 24
drwxr-xr-x 3 2000 2000 4096 Oct 28 13:34 .
drwxr-xr-x 31 root root 4096 Oct 28 13:39 ..
drwx------ 2 2000 2000 16384 Oct 28 13:34 lost+found
Let's create another example where we idmap the rootfs filesystem
without a mapping for uid 0 and gid 0:
# Create an idmapped mount of for a full POSIX range of rootfs under
# /mnt but without a mapping for uid 0 to reduce attack surface
root@f2-vm:/# ./mount-idmapped --map-mount b:1:1:65536 / /mnt/
# Since we don't have a mapping for uid and gid 0 all files owned by
# uid and gid 0 should show up as uid and gid 65534:
root@f2-vm:/# ls -al /mnt/
total 664
drwxr-xr-x 31 nobody nogroup 4096 Oct 28 13:39 .
drwxr-xr-x 31 root root 4096 Oct 28 13:39 ..
lrwxrwxrwx 1 nobody nogroup 7 Aug 25 07:44 bin -> usr/bin
drwxr-xr-x 4 nobody nogroup 4096 Oct 28 13:17 boot
drwxr-xr-x 2 nobody nogroup 4096 Aug 25 07:48 dev
drwxr-xr-x 81 nobody nogroup 4096 Oct 28 04:00 etc
drwxr-xr-x 4 nobody nogroup 4096 Oct 28 04:00 home
lrwxrwxrwx 1 nobody nogroup 7 Aug 25 07:44 lib -> usr/lib
lrwxrwxrwx 1 nobody nogroup 9 Aug 25 07:44 lib32 -> usr/lib32
lrwxrwxrwx 1 nobody nogroup 9 Aug 25 07:44 lib64 -> usr/lib64
lrwxrwxrwx 1 nobody nogroup 10 Aug 25 07:44 libx32 -> usr/libx32
drwx------ 2 nobody nogroup 16384 Aug 25 07:47 lost+found
drwxr-xr-x 2 nobody nogroup 4096 Aug 25 07:44 media
drwxr-xr-x 31 nobody nogroup 4096 Oct 28 13:39 mnt
drwxr-xr-x 2 nobody nogroup 4096 Aug 25 07:44 opt
drwxr-xr-x 2 nobody nogroup 4096 Apr 15 2020 proc
drwx--x--x 6 nobody nogroup 4096 Oct 28 13:34 root
drwxr-xr-x 2 nobody nogroup 4096 Aug 25 07:46 run
lrwxrwxrwx 1 nobody nogroup 8 Aug 25 07:44 sbin -> usr/sbin
drwxr-xr-x 2 nobody nogroup 4096 Aug 25 07:44 srv
drwxr-xr-x 2 nobody nogroup 4096 Apr 15 2020 sys
drwxrwxrwt 10 nobody nogroup 4096 Oct 28 13:19 tmp
drwxr-xr-x 14 nobody nogroup 4096 Oct 20 13:00 usr
drwxr-xr-x 12 nobody nogroup 4096 Aug 25 07:45 var
# Since we do have a mapping for uid and gid 1000 all files owned by
# uid and gid 1000 should simply show up as uid and gid 1000:
root@f2-vm:/# ls -al /mnt/home/ubuntu/
total 40
drwxr-xr-x 3 ubuntu ubuntu 4096 Oct 28 00:43 .
drwxr-xr-x 4 nobody nogroup 4096 Oct 28 04:00 ..
-rw------- 1 ubuntu ubuntu 2936 Oct 28 12:26 .bash_history
-rw-r--r-- 1 ubuntu ubuntu 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 ubuntu ubuntu 807 Feb 25 2020 .profile
-rw-r--r-- 1 ubuntu ubuntu 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo
Link: https://lore.kernel.org/r/20210121131959.646623-39-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-ext4@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
* For the new fast_commit feature
* Fix some error handling codepaths in whiteout handling and
mountpoint sampling
* Fix how we write ext4_error information so it goes through the journal
when journalling is active, to avoid races that can lead to lost
error information, superblock checksum failures, or DIF/DIX features.
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Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 fixes from Ted Ts'o:
"A number of bug fixes for ext4:
- Fix for the new fast_commit feature
- Fix some error handling codepaths in whiteout handling and
mountpoint sampling
- Fix how we write ext4_error information so it goes through the
journal when journalling is active, to avoid races that can lead to
lost error information, superblock checksum failures, or DIF/DIX
features"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: remove expensive flush on fast commit
ext4: fix bug for rename with RENAME_WHITEOUT
ext4: fix wrong list_splice in ext4_fc_cleanup
ext4: use IS_ERR instead of IS_ERR_OR_NULL and set inode null when IS_ERR
ext4: don't leak old mountpoint samples
ext4: drop ext4_handle_dirty_super()
ext4: fix superblock checksum failure when setting password salt
ext4: use sbi instead of EXT4_SB(sb) in ext4_update_super()
ext4: save error info to sb through journal if available
ext4: protect superblock modifications with a buffer lock
ext4: drop sync argument of ext4_commit_super()
ext4: combine ext4_handle_error() and save_error_info()
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 updates from Ted Ts'o:
"Various bug fixes and cleanups for ext4; no new features this cycle"
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (29 commits)
ext4: remove unnecessary wbc parameter from ext4_bio_write_page
ext4: avoid s_mb_prefetch to be zero in individual scenarios
ext4: defer saving error info from atomic context
ext4: simplify ext4 error translation
ext4: move functions in super.c
ext4: make ext4_abort() use __ext4_error()
ext4: standardize error message in ext4_protect_reserved_inode()
ext4: remove redundant sb checksum recomputation
ext4: don't remount read-only with errors=continue on reboot
ext4: fix deadlock with fs freezing and EA inodes
jbd2: add a helper to find out number of fast commit blocks
ext4: make fast_commit.h byte identical with e2fsprogs/fast_commit.h
ext4: fix fall-through warnings for Clang
ext4: add docs about fast commit idempotence
ext4: remove the unused EXT4_CURRENT_REV macro
ext4: fix an IS_ERR() vs NULL check
ext4: check for invalid block size early when mounting a file system
ext4: fix a memory leak of ext4_free_data
ext4: delete nonsensical (commented-out) code inside ext4_xattr_block_set()
ext4: update ext4_data_block_valid related comments
...
If journalling is still working at the moment we get to writing error
information to the superblock we cannot write directly to the superblock
as such write could race with journalled update of the superblock and
cause journal checksum failures, writing inconsistent information to the
journal or other problems. We cannot journal the superblock directly
from the error handling functions as we are running in uncertain context
and could deadlock so just punt journalled superblock update to a
workqueue.
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20201216101844.22917-5-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Protect all superblock modifications (including checksum computation)
with a superblock buffer lock. That way we are sure computed checksum
matches current superblock contents (a mismatch could cause checksum
failures in nojournal mode or if an unjournalled superblock update races
with a journalled one). Also we avoid modifying superblock contents
while it is being written out (which can cause DIF/DIX failures if we
are running in nojournal mode).
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20201216101844.22917-4-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Everybody passes 1 as sync argument of ext4_commit_super(). Just drop
it.
Reviewed-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20201216101844.22917-3-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
save_error_info() is always called together with ext4_handle_error().
Combine them into a single call and move unconditional bits out of
save_error_info() into ext4_handle_error().
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20201216101844.22917-2-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
When filesystem inconsistency is detected with group locked, we
currently try to modify superblock to store error there without
blocking. However this can cause superblock checksum failures (or
DIF/DIX failure) when the superblock is just being written out.
Make error handling code just store error information in ext4_sb_info
structure and copy it to on-disk superblock only in ext4_commit_super().
In case of error happening with group locked, we just postpone the
superblock flushing to a workqueue.
[ Added fixup so that s_first_error_* does not get updated after
the file system is remounted.
Also added fix for syzbot failure. - Ted ]
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20201127113405.26867-8-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Hillf Danton <hdanton@sina.com>
Reported-by: syzbot+9043030c040ce1849a60@syzkaller.appspotmail.com
In this round, we've made more work into per-file compression support. For
example, F2FS_IOC_GET|SET_COMPRESS_OPTION provides a way to change the
algorithm or cluster size per file. F2FS_IOC_COMPRESS|DECOMPRESS_FILE provides
a way to compress and decompress the existing normal files manually along with
a new mount option, compress_mode=fs|user, which can control who compresses the
data. Chao also added a checksum feature with a mount option so that we are able
to detect any corrupted cluster. In addition, Daniel contributed casefolding
with encryption patch, which will be used for Android devices.
Enhancement:
- add ioctls and mount option to manage per-file compression feature
- support casefolding with encryption
- support checksum for compressed cluster
- avoid IO starvation by replacing mutex with rwsem
- add sysfs, max_io_bytes, to control max bio size
Bug fix:
- fix use-after-free issue when compression and fsverity are enabled
- fix consistency corruption during fault injection test
- fix data offset for lseek
- get rid of buffer_head which has 32bits limit in fiemap
- fix some bugs in multi-partitions support
- fix nat entry count calculation in shrinker
- fix some stat information
And, we've refactored some logics and fix minor bugs as well.
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Merge tag 'f2fs-for-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this round, we've made more work into per-file compression support.
For example, F2FS_IOC_GET | SET_COMPRESS_OPTION provides a way to
change the algorithm or cluster size per file. F2FS_IOC_COMPRESS |
DECOMPRESS_FILE provides a way to compress and decompress the existing
normal files manually.
There is also a new mount option, compress_mode=fs|user, which can
control who compresses the data.
Chao also added a checksum feature with a mount option so that
we are able to detect any corrupted cluster.
In addition, Daniel contributed casefolding with encryption patch,
which will be used for Android devices.
Summary:
Enhancements:
- add ioctls and mount option to manage per-file compression feature
- support casefolding with encryption
- support checksum for compressed cluster
- avoid IO starvation by replacing mutex with rwsem
- add sysfs, max_io_bytes, to control max bio size
Bug fixes:
- fix use-after-free issue when compression and fsverity are enabled
- fix consistency corruption during fault injection test
- fix data offset for lseek
- get rid of buffer_head which has 32bits limit in fiemap
- fix some bugs in multi-partitions support
- fix nat entry count calculation in shrinker
- fix some stat information
And, we've refactored some logics and fix minor bugs as well"
* tag 'f2fs-for-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (36 commits)
f2fs: compress: fix compression chksum
f2fs: fix shift-out-of-bounds in sanity_check_raw_super()
f2fs: fix race of pending_pages in decompression
f2fs: fix to account inline xattr correctly during recovery
f2fs: inline: fix wrong inline inode stat
f2fs: inline: correct comment in f2fs_recover_inline_data
f2fs: don't check PAGE_SIZE again in sanity_check_raw_super()
f2fs: convert to F2FS_*_INO macro
f2fs: introduce max_io_bytes, a sysfs entry, to limit bio size
f2fs: don't allow any writes on readonly mount
f2fs: avoid race condition for shrinker count
f2fs: add F2FS_IOC_DECOMPRESS_FILE and F2FS_IOC_COMPRESS_FILE
f2fs: add compress_mode mount option
f2fs: Remove unnecessary unlikely()
f2fs: init dirty_secmap incorrectly
f2fs: remove buffer_head which has 32bits limit
f2fs: fix wrong block count instead of bytes
f2fs: use new conversion functions between blks and bytes
f2fs: rename logical_to_blk and blk_to_logical
f2fs: fix kbytes written stat for multi-device case
...
We convert errno's to ext4 on-disk format error codes in
save_error_info(). Add a function and a bit of macro magic to make this
simpler.
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/20201127113405.26867-7-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Just move error info related functions in super.c close to
ext4_handle_error(). We'll want to combine save_error_info() with
ext4_handle_error() and this makes change more obvious and saves a
forward declaration as well. No functional change.
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/20201127113405.26867-6-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The only difference between __ext4_abort() and __ext4_error() is that
the former one ignores errors=continue mount option. Unify the code to
reduce duplication.
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/20201127113405.26867-5-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Superblock is written out either through ext4_commit_super() or through
ext4_handle_dirty_super(). In both cases we recompute the checksum so it
is not necessary to recompute it after updating superblock free inodes &
blocks counters.
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/20201127113405.26867-3-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
ext4_handle_error() with errors=continue mount option can accidentally
remount the filesystem read-only when the system is rebooting. Fix that.
Fixes: 1dc1097ff6 ("ext4: avoid panic during forced reboot")
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Cc: stable@kernel.org
Link: https://lore.kernel.org/r/20201127113405.26867-2-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
