This commit adds mount option 'zero_size_dir'. If this option
enabled, don't allocate a cluster to directory when creating
it, and set the directory size to 0.
On Windows, a cluster is allocated for a directory when it is
created, so the mount option is disabled by default.
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
After repairing a corrupted file system with exfatprogs' fsck.exfat,
zero-size directories may result. It is also possible to create
zero-size directories in other exFAT implementation, such as Paragon
ufsd dirver.
As described in the specification, the lower directory size limits
is 0 bytes.
Without this commit, sub-directories and files cannot be created
under a zero-size directory, and it cannot be removed.
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Add GET and SET attributes ioctls to enable attribute modification.
We already do this in FAT and a few userspace utils made for it would
benefit from this also working on exFAT, namely fatattr.
Signed-off-by: Jan Cincera <hcincera@gmail.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
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Merge tag 'for-6.6/block-2023-08-28' of git://git.kernel.dk/linux
Pull block updates from Jens Axboe:
"Pretty quiet round for this release. This contains:
- Add support for zoned storage to ublk (Andreas, Ming)
- Series improving performance for drivers that mark themselves as
needing a blocking context for issue (Bart)
- Cleanup the flush logic (Chengming)
- sed opal keyring support (Greg)
- Fixes and improvements to the integrity support (Jinyoung)
- Add some exports for bcachefs that we can hopefully delete again in
the future (Kent)
- deadline throttling fix (Zhiguo)
- Series allowing building the kernel without buffer_head support
(Christoph)
- Sanitize the bio page adding flow (Christoph)
- Write back cache fixes (Christoph)
- MD updates via Song:
- Fix perf regression for raid0 large sequential writes (Jan)
- Fix split bio iostat for raid0 (David)
- Various raid1 fixes (Heinz, Xueshi)
- raid6test build fixes (WANG)
- Deprecate bitmap file support (Christoph)
- Fix deadlock with md sync thread (Yu)
- Refactor md io accounting (Yu)
- Various non-urgent fixes (Li, Yu, Jack)
- Various fixes and cleanups (Arnd, Azeem, Chengming, Damien, Li,
Ming, Nitesh, Ruan, Tejun, Thomas, Xu)"
* tag 'for-6.6/block-2023-08-28' of git://git.kernel.dk/linux: (113 commits)
block: use strscpy() to instead of strncpy()
block: sed-opal: keyring support for SED keys
block: sed-opal: Implement IOC_OPAL_REVERT_LSP
block: sed-opal: Implement IOC_OPAL_DISCOVERY
blk-mq: prealloc tags when increase tagset nr_hw_queues
blk-mq: delete redundant tagset map update when fallback
blk-mq: fix tags leak when shrink nr_hw_queues
ublk: zoned: support REQ_OP_ZONE_RESET_ALL
md: raid0: account for split bio in iostat accounting
md/raid0: Fix performance regression for large sequential writes
md/raid0: Factor out helper for mapping and submitting a bio
md raid1: allow writebehind to work on any leg device set WriteMostly
md/raid1: hold the barrier until handle_read_error() finishes
md/raid1: free the r1bio before waiting for blocked rdev
md/raid1: call free_r1bio() before allow_barrier() in raid_end_bio_io()
blk-cgroup: Fix NULL deref caused by blkg_policy_data being installed before init
drivers/rnbd: restore sysfs interface to rnbd-client
md/raid5-cache: fix null-ptr-deref for r5l_flush_stripe_to_raid()
raid6: test: only check for Altivec if building on powerpc hosts
raid6: test: make sure all intermediate and artifact files are .gitignored
...
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Merge tag 'v6.6-vfs.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull superblock updates from Christian Brauner:
"This contains the super rework that was ready for this cycle. The
first part changes the order of how we open block devices and allocate
superblocks, contains various cleanups, simplifications, and a new
mechanism to wait on superblock state changes.
This unblocks work to ultimately limit the number of writers to a
block device. Jan has already scheduled follow-up work that will be
ready for v6.7 and allows us to restrict the number of writers to a
given block device. That series builds on this work right here.
The second part contains filesystem freezing updates.
Overview:
The generic superblock changes are rougly organized as follows
(ignoring additional minor cleanups):
(1) Removal of the bd_super member from struct block_device.
This was a very odd back pointer to struct super_block with
unclear rules. For all relevant places we have other means to get
the same information so just get rid of this.
(2) Simplify rules for superblock cleanup.
Roughly, everything that is allocated during fs_context
initialization and that's stored in fs_context->s_fs_info needs
to be cleaned up by the fs_context->free() implementation before
the superblock allocation function has been called successfully.
After sget_fc() returned fs_context->s_fs_info has been
transferred to sb->s_fs_info at which point sb->kill_sb() if
fully responsible for cleanup. Adhering to these rules means that
cleanup of sb->s_fs_info in fill_super() is to be avoided as it's
brittle and inconsistent.
Cleanup shouldn't be duplicated between sb->put_super() as
sb->put_super() is only called if sb->s_root has been set aka
when the filesystem has been successfully born (SB_BORN). That
complexity should be avoided.
This also means that block devices are to be closed in
sb->kill_sb() instead of sb->put_super(). More details in the
lower section.
(3) Make it possible to lookup or create a superblock before opening
block devices
There's a subtle dependency on (2) as some filesystems did rely
on fill_super() to be called in order to correctly clean up
sb->s_fs_info. All these filesystems have been fixed.
(4) Switch most filesystem to follow the same logic as the generic
mount code now does as outlined in (3).
(5) Use the superblock as the holder of the block device. We can now
easily go back from block device to owning superblock.
(6) Export and extend the generic fs_holder_ops and use them as
holder ops everywhere and remove the filesystem specific holder
ops.
(7) Call from the block layer up into the filesystem layer when the
block device is removed, allowing to shut down the filesystem
without risk of deadlocks.
(8) Get rid of get_super().
We can now easily go back from the block device to owning
superblock and can call up from the block layer into the
filesystem layer when the device is removed. So no need to wade
through all registered superblock to find the owning superblock
anymore"
Link: https://lore.kernel.org/lkml/20230824-prall-intakt-95dbffdee4a0@brauner/
* tag 'v6.6-vfs.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (47 commits)
super: use higher-level helper for {freeze,thaw}
super: wait until we passed kill super
super: wait for nascent superblocks
super: make locking naming consistent
super: use locking helpers
fs: simplify invalidate_inodes
fs: remove get_super
block: call into the file system for ioctl BLKFLSBUF
block: call into the file system for bdev_mark_dead
block: consolidate __invalidate_device and fsync_bdev
block: drop the "busy inodes on changed media" log message
dasd: also call __invalidate_device when setting the device offline
amiflop: don't call fsync_bdev in FDFMTBEG
floppy: call disk_force_media_change when changing the format
block: simplify the disk_force_media_change interface
nbd: call blk_mark_disk_dead in nbd_clear_sock_ioctl
xfs use fs_holder_ops for the log and RT devices
xfs: drop s_umount over opening the log and RT devices
ext4: use fs_holder_ops for the log device
ext4: drop s_umount over opening the log device
...
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Merge tag 'v6.6-vfs.ctime' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs timestamp updates from Christian Brauner:
"This adds VFS support for multi-grain timestamps and converts tmpfs,
xfs, ext4, and btrfs to use them. This carries acks from all relevant
filesystems.
The VFS always uses coarse-grained timestamps when updating the ctime
and mtime after a change. This has the benefit of allowing filesystems
to optimize away a lot of metadata updates, down to around 1 per
jiffy, even when a file is under heavy writes.
Unfortunately, this has always been an issue when we're exporting via
NFSv3, which relies on timestamps to validate caches. A lot of changes
can happen in a jiffy, so timestamps aren't sufficient to help the
client decide to invalidate the cache.
Even with NFSv4, a lot of exported filesystems don't properly support
a change attribute and are subject to the same problems with timestamp
granularity. Other applications have similar issues with timestamps
(e.g., backup applications).
If we were to always use fine-grained timestamps, that would improve
the situation, but that becomes rather expensive, as the underlying
filesystem would have to log a lot more metadata updates.
This introduces fine-grained timestamps that are used when they are
actively queried.
This uses the 31st bit of the ctime tv_nsec field to indicate that
something has queried the inode for the mtime or ctime. When this flag
is set, on the next mtime or ctime update, the kernel will fetch a
fine-grained timestamp instead of the usual coarse-grained one.
As POSIX generally mandates that when the mtime changes, the ctime
must also change the kernel always stores normalized ctime values, so
only the first 30 bits of the tv_nsec field are ever used.
Filesytems can opt into this behavior by setting the FS_MGTIME flag in
the fstype. Filesystems that don't set this flag will continue to use
coarse-grained timestamps.
Various preparatory changes, fixes and cleanups are included:
- Fixup all relevant places where POSIX requires updating ctime
together with mtime. This is a wide-range of places and all
maintainers provided necessary Acks.
- Add new accessors for inode->i_ctime directly and change all
callers to rely on them. Plain accesses to inode->i_ctime are now
gone and it is accordingly rename to inode->__i_ctime and commented
as requiring accessors.
- Extend generic_fillattr() to pass in a request mask mirroring in a
sense the statx() uapi. This allows callers to pass in a request
mask to only get a subset of attributes filled in.
- Rework timestamp updates so it's possible to drop the @now
parameter the update_time() inode operation and associated helpers.
- Add inode_update_timestamps() and convert all filesystems to it
removing a bunch of open-coding"
* tag 'v6.6-vfs.ctime' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (107 commits)
btrfs: convert to multigrain timestamps
ext4: switch to multigrain timestamps
xfs: switch to multigrain timestamps
tmpfs: add support for multigrain timestamps
fs: add infrastructure for multigrain timestamps
fs: drop the timespec64 argument from update_time
xfs: have xfs_vn_update_time gets its own timestamp
fat: make fat_update_time get its own timestamp
fat: remove i_version handling from fat_update_time
ubifs: have ubifs_update_time use inode_update_timestamps
btrfs: have it use inode_update_timestamps
fs: drop the timespec64 arg from generic_update_time
fs: pass the request_mask to generic_fillattr
fs: remove silly warning from current_time
gfs2: fix timestamp handling on quota inodes
fs: rename i_ctime field to __i_ctime
selinux: convert to ctime accessor functions
security: convert to ctime accessor functions
apparmor: convert to ctime accessor functions
sunrpc: convert to ctime accessor functions
...
As a rule of thumb everything allocated to the fs_context and moved into
the super_block should be freed by ->kill_sb so that the teardown
handling doesn't need to be duplicated between the fill_super error
path and put_super. Implement an exfat-specific kill_sb method to do
that and share the code with the mount contex free helper for the
mount error handling case.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Message-Id: <20230809220545.1308228-11-hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
There are no RCU critical sections for accessing any information in the
sbi, so drop the call_rcu indirection for freeing the sbi.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Message-Id: <20230809220545.1308228-10-hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
generic_fillattr just fills in the entire stat struct indiscriminately
today, copying data from the inode. There is at least one attribute
(STATX_CHANGE_COOKIE) that can have side effects when it is reported,
and we're looking at adding more with the addition of multigrain
timestamps.
Add a request_mask argument to generic_fillattr and have most callers
just pass in the value that is passed to getattr. Have other callers
(e.g. ksmbd) just pass in STATX_BASIC_STATS. Also move the setting of
STATX_CHANGE_COOKIE into generic_fillattr.
Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: "Paulo Alcantara (SUSE)" <pc@manguebit.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230807-mgctime-v7-2-d1dec143a704@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
All users now just use '->iterate_shared()', which only takes the
directory inode lock for reading.
Filesystems that never got convered to shared mode now instead use a
wrapper that drops the lock, re-takes it in write mode, calls the old
function, and then downgrades the lock back to read mode.
This way the VFS layer and other callers no longer need to care about
filesystems that never got converted to the modern era.
The filesystems that use the new wrapper are ceph, coda, exfat, jfs,
ntfs, ocfs2, overlayfs, and vboxsf.
Honestly, several of them look like they really could just iterate their
directories in shared mode and skip the wrapper entirely, but the point
of this change is to not change semantics or fix filesystems that
haven't been fixed in the last 7+ years, but to finally get rid of the
dual iterators.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Add a new config option that controls building the buffer_head code, and
select it from all file systems and stacking drivers that need it.
For the block device nodes and alternative iomap based buffered I/O path
is provided when buffer_head support is not enabled, and iomap needs a
a small tweak to define the IOMAP_F_BUFFER_HEAD flag to 0 to not call
into the buffer_head code when it doesn't exist.
Otherwise this is just Kconfig and ifdef changes.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20230801172201.1923299-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
exfat_extract_uni_name copies characters from a given file name entry into
the 'uniname' variable. This variable is actually defined on the stack of
the exfat_readdir() function. According to the definition of
the 'exfat_uni_name' type, the file name should be limited 255 characters
(+ null teminator space), but the exfat_get_uniname_from_ext_entry()
function can write more characters because there is no check if filename
entries exceeds max filename length. This patch add the check not to copy
filename characters when exceeding max filename length.
Cc: stable@vger.kernel.org
Cc: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reported-by: Maxim Suhanov <dfirblog@gmail.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
In later patches, we're going to change how the inode's ctime field is
used. Switch to using accessor functions instead of raw accesses of
inode->i_ctime.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Message-Id: <20230705190309.579783-38-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
The call stack shown below is a scenario in the Linux 4.19 kernel.
Allocating memory failed where exfat fs use kmalloc_array due to
system memory fragmentation, while the u-disk was inserted without
recognition.
Devices such as u-disk using the exfat file system are pluggable and
may be insert into the system at any time.
However, long-term running systems cannot guarantee the continuity of
physical memory. Therefore, it's necessary to address this issue.
Binder:2632_6: page allocation failure: order:4,
mode:0x6040c0(GFP_KERNEL|__GFP_COMP), nodemask=(null)
Call trace:
[242178.097582] dump_backtrace+0x0/0x4
[242178.097589] dump_stack+0xf4/0x134
[242178.097598] warn_alloc+0xd8/0x144
[242178.097603] __alloc_pages_nodemask+0x1364/0x1384
[242178.097608] kmalloc_order+0x2c/0x510
[242178.097612] kmalloc_order_trace+0x40/0x16c
[242178.097618] __kmalloc+0x360/0x408
[242178.097624] load_alloc_bitmap+0x160/0x284
[242178.097628] exfat_fill_super+0xa3c/0xe7c
[242178.097635] mount_bdev+0x2e8/0x3a0
[242178.097638] exfat_fs_mount+0x40/0x50
[242178.097643] mount_fs+0x138/0x2e8
[242178.097649] vfs_kern_mount+0x90/0x270
[242178.097655] do_mount+0x798/0x173c
[242178.097659] ksys_mount+0x114/0x1ac
[242178.097665] __arm64_sys_mount+0x24/0x34
[242178.097671] el0_svc_common+0xb8/0x1b8
[242178.097676] el0_svc_handler+0x74/0x90
[242178.097681] el0_svc+0x8/0x340
By analyzing the exfat code,we found that continuous physical memory
is not required here,so kvmalloc_array is used can solve this problem.
Cc: stable@vger.kernel.org
Signed-off-by: gaoming <gaoming20@hihonor.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
A rename potentially involves updating 4 different inode timestamps.
Convert to the new simple_rename_timestamp helper function.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-10-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
When removing entries from a directory, the ctime must also be updated
alongside the mtime.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Message-Id: <20230705190309.579783-4-jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
- Handle vendor extension and allocation entries as unrecognized benign secondary entries.
- Fix wrong ->i_blocks on devices with non-512 byte sector.
- Add the check to avoid returning -EIO from exfat_readdir() at current position exceeding the directory size.
- Fix a bug that reach the end of the directory stream at a position not aligned with the dentry size.
- Redefine DIR_DELETED as 0xFFFFFFF7, the bad cluster number.
- Two cleanup fixes and fix cluster leakage in error handling.
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Merge tag 'exfat-for-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat
Pull exfat updates from Namjae Jeon:
- Handle vendor extension and allocation entries as unrecognized benign
secondary entries
- Fix wrong ->i_blocks on devices with non-512 byte sector
- Add the check to avoid returning -EIO from exfat_readdir() at current
position exceeding the directory size
- Fix a bug that reach the end of the directory stream at a position
not aligned with the dentry size
- Redefine DIR_DELETED as 0xFFFFFFF7, the bad cluster number
- Two cleanup fixes and fix cluster leakage in error handling
* tag 'exfat-for-6.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat:
exfat: fix the newly allocated clusters are not freed in error handling
exfat: don't print error log in normal case
exfat: remove unneeded code from exfat_alloc_cluster()
exfat: handle unreconized benign secondary entries
exfat: fix inode->i_blocks for non-512 byte sector size device
exfat: redefine DIR_DELETED as the bad cluster number
exfat: fix reporting fs error when reading dir beyond EOF
exfat: fix unexpected EOF while reading dir
In error handling 'free_cluster', before num_alloc clusters allocated,
p_chain->size will not updated and always 0, thus the newly allocated
clusters are not freed.
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
When allocating a new cluster, exFAT first allocates from the
next cluster of the last cluster of the file. If the last cluster
of the file is the last cluster of the volume, allocate from the
first cluster. This is a normal case, but the following error log
will be printed. It makes users confused, so this commit removes
the error log.
[1960905.181545] exFAT-fs (sdb1): hint_cluster is invalid (262130)
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
In the removed code, num_clusters is 0, nothing is done in
exfat_chain_cont_cluster(), so it is unneeded, remove it.
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Sony PXW-Z280 camera add vendor allocation entries to directory of
pictures. Currently, linux exfat does not support it and the file is
not visible. This patch handle vendor extension and allocation entries
as unreconized benign secondary entries. As described in the specification,
it is recognized but ignored, and when deleting directory entry set,
the associated clusters allocation are removed as well as benign secondary
directory entries.
Reported-by: Barócsi Dénes <admin@tveger.hu>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Reviewed-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
inode->i_blocks is not real number of blocks, but 512 byte ones.
Fixes: 98d917047e ("exfat: add file operations")
Cc: stable@vger.kernel.org # v5.7+
Reported-by: Wang Yugui <wangyugui@e16-tech.com>
Tested-by: Wang Yugui <wangyugui@e16-tech.com>
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
When a file or a directory is deleted, the hint for the cluster of
its parent directory in its in-memory inode is set as DIR_DELETED.
Therefore, DIR_DELETED must be one of invalid cluster numbers. According
to the exFAT specification, a volume can have at most 2^32-11 clusters.
However, DIR_DELETED is wrongly defined as 0xFFFF0321, which could be
a valid cluster number. To fix it, let's redefine DIR_DELETED as
0xFFFFFFF7, the bad cluster number.
Fixes: 1acf1a564b ("exfat: add in-memory and on-disk structures and headers")
Cc: stable@vger.kernel.org # v5.7+
Reported-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Signed-off-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Since seekdir() does not check whether the position is valid, the
position may exceed the size of the directory. We found that for
a directory with discontinuous clusters, if the position exceeds
the size of the directory and the excess size is greater than or
equal to the cluster size, exfat_readdir() will return -EIO,
causing a file system error and making the file system unavailable.
Reproduce this bug by:
seekdir(dir, dir_size + cluster_size);
dirent = readdir(dir);
The following log will be printed if mount with 'errors=remount-ro'.
[11166.712896] exFAT-fs (sdb1): error, invalid access to FAT (entry 0xffffffff)
[11166.712905] exFAT-fs (sdb1): Filesystem has been set read-only
Fixes: 1e5654de0f ("exfat: handle wrong stream entry size in exfat_readdir()")
Cc: stable@vger.kernel.org # v5.7+
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
If the position is not aligned with the dentry size, the return
value of readdir() will be NULL and errno is 0, which means the
end of the directory stream is reached.
If the position is aligned with dentry size, but there is no file
or directory at the position, exfat_readdir() will continue to
get dentry from the next dentry. So the dentry gotten by readdir()
may not be at the position.
After this commit, if the position is not aligned with the dentry
size, round the position up to the dentry size and continue to get
the dentry.
Fixes: ca06197382 ("exfat: add directory operations")
Cc: stable@vger.kernel.org # v5.7+
Reported-by: Wang Yugui <wangyugui@e16-tech.com>
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
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Merge tag 'for-6.3/dio-2023-02-16' of git://git.kernel.dk/linux
Pull legacy dio update from Jens Axboe:
"We only have a few file systems that use the old dio code, make them
select it rather than build it unconditionally"
* tag 'for-6.3/dio-2023-02-16' of git://git.kernel.dk/linux:
fs: build the legacy direct I/O code conditionally
fs: move sb_init_dio_done_wq out of direct-io.c
Add a new LEGACY_DIRECT_IO config symbol that is only selected by the
file systems that still use the legacy blockdev_direct_IO code, so that
kernels without support for those file systems don't need to build the
code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20230125065839.191256-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Convert to struct mnt_idmap.
Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.
Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.
Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Convert to struct mnt_idmap.
Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.
Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.
Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Convert to struct mnt_idmap.
Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.
Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.
Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Convert to struct mnt_idmap.
Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.
Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.
Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Convert to struct mnt_idmap.
Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.
Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.
Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
- simplify and remove some redundant codes handing directory entries
- optimize the size of exfat_entry_set_cache and its allocation policy
- improve the performance for creating files and directories
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Merge tag 'exfat-for-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat
Pull exfat update from Namjae Jeon:
- simplify and remove some redundant directory entry code
- optimize the size of exfat_entry_set_cache and its allocation policy
- improve the performance for creating files and directories
* tag 'exfat-for-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat:
exfat: reuse exfat_find_location() to simplify exfat_get_dentry_set()
exfat: fix overflow in sector and cluster conversion
exfat: remove i_size_write() from __exfat_truncate()
exfat: remove argument 'size' from exfat_truncate()
exfat: remove unnecessary arguments from exfat_find_dir_entry()
exfat: remove unneeded codes from __exfat_rename()
exfat: remove call ilog2() from exfat_readdir()
exfat: replace magic numbers with Macros
exfat: rename exfat_free_dentry_set() to exfat_put_dentry_set()
exfat: move exfat_entry_set_cache from heap to stack
exfat: support dynamic allocate bh for exfat_entry_set_cache
exfat: reduce the size of exfat_entry_set_cache
exfat: hint the empty entry which at the end of cluster chain
exfat: simplify empty entry hint
In exfat_get_dentry_set(), part of the code is the same as
exfat_find_location(), reuse exfat_find_location() to simplify
exfat_get_dentry_set().
Code refinement, no functional changes.
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
According to the exFAT specification, there are at most 2^32-11
clusters in a volume. so using 'int' is not enough for cluster
index, the return value type of exfat_sector_to_cluster() should
be 'unsigned int'.
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Patch series "start removing writepage instances v2".
The VM doesn't need or want ->writepage for writeback and is fine with
just having ->writepages as long as ->migrate_folio is implemented.
This series removes all ->writepage instances that use
block_write_full_page directly and also have a plain mpage_writepages
based ->writepages.
This patch (of 7):
->writepage is a very inefficient method to write back data, and only used
through write_cache_pages or a a fallback when no ->migrate_folio method
is present.
Set ->migrate_folio to the generic buffer_head based helper, and remove
the ->writepage implementation.
Link: https://lkml.kernel.org/r/20221202102644.770505-1-hch@lst.de
Link: https://lkml.kernel.org/r/20221202102644.770505-2-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Bob Copeland <me@bobcopeland.com>
Cc: Dave Kleikamp <shaggy@kernel.org>
Cc: Jan Kara <jack@suse.com>
Cc: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The file/directory size is updated into inode by i_size_write()
before __exfat_truncate() is called, so it is redundant to
re-update by i_size_write() in __exfat_truncate().
Code refinement, no functional changes.
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
argument 'size' is not used in exfat_truncate(), remove it.
Code refinement, no functional changes.
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
This commit removes argument 'num_entries' and 'type' from
exfat_find_dir_entry().
Code refinement, no functional changes.
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
The code gets the dentry, but the dentry is not used, remove the
code.
Code refinement, no functional changes.
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
There is no need to call ilog2() for the conversions between
cluster and dentry in exfat_readdir(), because these conversions
can be replaced with EXFAT_DEN_TO_CLU()/EXFAT_CLU_TO_DEN().
Code refinement, no functional changes.
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Since struct exfat_entry_set_cache is allocated from stack,
no need to free, so rename exfat_free_dentry_set() to
exfat_put_dentry_set(). After renaming, the new function pair
is exfat_get_dentry_set()/exfat_put_dentry_set().
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
The size of struct exfat_entry_set_cache is only 56 bytes on
64-bit system, and allocating from stack is more efficient than
allocating from heap.
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
In special cases, a file or a directory may occupied more than 19
directory entries, pre-allocating 3 bh is not enough. Such as
- Support vendor secondary directory entry in the future.
- Since file directory entry is damaged, the SecondaryCount
field is bigger than 18.
So this commit supports dynamic allocation of bh.
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
In normal, there are 19 directory entries at most for a file or
a directory.
- A file directory entry
- A stream extension directory entry
- 1~17 file name directory entry
So the directory entries are in 3 sectors at most, it is enough
for struct exfat_entry_set_cache to pre-allocate 3 bh.
This commit changes the size of struct exfat_entry_set_cache as:
Before After
32-bit system 88 32 bytes
64-bit system 168 48 bytes
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
After traversing all directory entries, hint the empty directory
entry no matter whether or not there are enough empty directory
entries.
After this commit, hint the empty directory entries like this:
1. Hint the deleted directory entries if enough;
2. Hint the deleted and unused directory entries which at the
end of the cluster chain no matter whether enough or not(Add
by this commit);
3. If no any empty directory entries, hint the empty directory
entries in the new cluster(Add by this commit).
This avoids repeated traversal of directory entries, reduces CPU
usage, and improves the performance of creating files and
directories(especially on low-performance CPUs).
Test create 5000 files in a class 4 SD card on imx6q-sabrelite
with:
for ((i=0;i<5;i++)); do
sync
time (for ((j=1;j<=1000;j++)); do touch file$((i*1000+j)); done)
done
The more files, the more performance improvements.
Before After Improvement
1~1000 25.360s 22.168s 14.40%
1001~2000 38.242s 28.72ss 33.15%
2001~3000 49.134s 35.037s 40.23%
3001~4000 62.042s 41.624s 49.05%
4001~5000 73.629s 46.772s 57.42%
Signed-off-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Andy Wu <Andy.Wu@sony.com>
Reviewed-by: Aoyama Wataru <wataru.aoyama@sony.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
