The iput() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Richard Weinberger <richard@nod.at>
If ubifs_tnc_next_ent() returns something else than -ENOENT
we leak file->private_data.
Signed-off-by: Richard Weinberger <richard@nod.at>
Reviewed-by: David Gstir <david@sigma-star.at>
As currently new_valid_dev always returns 1, so new_valid_dev check is not
needed, remove it.
Signed-off-by: Yaowei Bai <bywxiaobai@163.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
This is a trivial fix of showing verbose message when leb-recovery detects
a corrupted node, which is not the last one in the LEB. Rescan expects to
show more detail of the corrupted node.
Reviewed-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Call dbg_is_power_cut() to emulate power cut instead of reading
c->dbg->pc_happened. Otherwise, the function becomes dead code.
Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
The patch was generated using fixed coccinelle semantic patch
scripts/coccinelle/api/memdup.cocci [1].
[1]: http://permalink.gmane.org/gmane.linux.kernel/2014320
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
* Minor fixes for UBI and UBIFS
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2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=xU0H
-----END PGP SIGNATURE-----
Merge tag 'upstream-4.2-rc1' of git://git.infradead.org/linux-ubifs
Pull UBI/UBIFS updates from Richard Weinberger:
"Minor fixes for UBI and UBIFS"
* tag 'upstream-4.2-rc1' of git://git.infradead.org/linux-ubifs:
UBI: Remove unnecessary `\'
UBI: Use static class and attribute groups
UBI: add a helper function for updatting on-flash layout volumes
UBI: Fastmap: Do not add vol if it already exists
UBI: Init vol->reserved_pebs by assignment
UBI: Fastmap: Rename variables to make them meaningful
UBI: Fastmap: Remove unnecessary `\'
UBI: Fastmap: Use max() to get the larger value
ubifs: fix to check error code of register_shrinker
UBI: block: Dynamically allocate minor numbers
register_shrinker() in ubifs_init() can fail due to fail to call kzalloc.
This patch fixes to check the return value of register_shrinker, otherwise
our shrinker may be unregistered after ubifs initialized successfully.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Pull fourth vfs update from Al Viro:
"d_inode() annotations from David Howells (sat in for-next since before
the beginning of merge window) + four assorted fixes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
RCU pathwalk breakage when running into a symlink overmounting something
fix I_DIO_WAKEUP definition
direct-io: only inc/dec inode->i_dio_count for file systems
fs/9p: fix readdir()
VFS: assorted d_backing_inode() annotations
VFS: fs/inode.c helpers: d_inode() annotations
VFS: fs/cachefiles: d_backing_inode() annotations
VFS: fs library helpers: d_inode() annotations
VFS: assorted weird filesystems: d_inode() annotations
VFS: normal filesystems (and lustre): d_inode() annotations
VFS: security/: d_inode() annotations
VFS: security/: d_backing_inode() annotations
VFS: net/: d_inode() annotations
VFS: net/unix: d_backing_inode() annotations
VFS: kernel/: d_inode() annotations
VFS: audit: d_backing_inode() annotations
VFS: Fix up some ->d_inode accesses in the chelsio driver
VFS: Cachefiles should perform fs modifications on the top layer only
VFS: AF_UNIX sockets should call mknod on the top layer only
* Powercut emulation for UBI
* A huge update to UBI Fastmap
* Cleanups and bugfixes all over UBI and UBIFS
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2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=nzVw
-----END PGP SIGNATURE-----
Merge tag 'upstream-4.1-rc1' of git://git.infradead.org/linux-ubifs
Pull UBI/UBIFS updates from Richard Weinberger:
"This pull request includes the following UBI/UBIFS changes:
- powercut emulation for UBI
- a huge update to UBI Fastmap
- cleanups and bugfixes all over UBI and UBIFS"
* tag 'upstream-4.1-rc1' of git://git.infradead.org/linux-ubifs: (50 commits)
UBI: power cut emulation for testing
UBIFS: fix output format of INUM_WATERMARK
UBI: Fastmap: Fall back to scanning mode after ECC error
UBI: Fastmap: Remove is_fm_block()
UBI: Fastmap: Add blank line after declarations
UBI: Fastmap: Remove else after return.
UBI: Fastmap: Introduce may_reserve_for_fm()
UBI: Fastmap: Introduce ubi_fastmap_init()
UBI: Fastmap: Wire up WL accessor functions
UBI: Add accessor functions for WL data structures
UBI: Move fastmap specific functions out of wl.c
UBI: Fastmap: Add new module parameter fm_debug
UBI: Fastmap: Make self_check_eba() depend on fastmap self checking
UBI: Fastmap: Add self check to detect absent PEBs
UBI: Fix stale pointers in ubi->lookuptbl
UBI: Fastmap: Enhance fastmap checking
UBI: Add initial support for fastmap self checks
UBI: Fastmap: Rework fastmap error paths
UBI: Fastmap: Prepare for variable sized fastmaps
UBI: Fastmap: Locking updates
...
that's the bulk of filesystem drivers dealing with inodes of their own
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The INUM_WATERMARK is a unsigned 32bit value, `%d' prints it as negatave:
[ 103.682255] UBIFS warning (ubi0:0 pid 691): ubifs_new_inode: running out of inode numbers (current 122763, max -256)
Fix it as:
[ 154.422940] UBIFS warning (ubi0:0 pid 688): ubifs_new_inode: running out of inode numbers (current 122765, max 4294967040)
Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
All places outside of core VFS that checked ->read and ->write for being NULL or
called the methods directly are gone now, so NULL {read,write} with non-NULL
{read,write}_iter will do the right thing in all cases.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
struct kiocb now is a generic I/O container, so move it to fs.h.
Also do a #include diet for aio.h while we're at it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
In the case where we have more than one volumes on different UBI
devices, it may be not that easy to tell which volume prints the
messages. Add ubi number and volume id in ubifs_msg/warn/error
to help debug. These two values are passed by struct ubifs_info.
For those where ubifs_info is not initialized yet, ubifs_* is
replaced by pr_*. For those where ubifs_info is not avaliable,
ubifs_info is passed to the calling function as a const parameter.
The output looks like,
[ 95.444879] UBIFS (ubi0:1): background thread "ubifs_bgt0_1" started, PID 696
[ 95.484688] UBIFS (ubi0:1): UBIFS: mounted UBI device 0, volume 1, name "test1"
[ 95.484694] UBIFS (ubi0:1): LEB size: 126976 bytes (124 KiB), min./max. I/O unit sizes: 2048 bytes/2048 bytes
[ 95.484699] UBIFS (ubi0:1): FS size: 30220288 bytes (28 MiB, 238 LEBs), journal size 1523712 bytes (1 MiB, 12 LEBs)
[ 95.484703] UBIFS (ubi0:1): reserved for root: 1427378 bytes (1393 KiB)
[ 95.484709] UBIFS (ubi0:1): media format: w4/r0 (latest is w4/r0), UUID 40DFFC0E-70BE-4193-8905-F7D6DFE60B17, small LPT model
[ 95.489875] UBIFS (ubi1:0): background thread "ubifs_bgt1_0" started, PID 699
[ 95.529713] UBIFS (ubi1:0): UBIFS: mounted UBI device 1, volume 0, name "test2"
[ 95.529718] UBIFS (ubi1:0): LEB size: 126976 bytes (124 KiB), min./max. I/O unit sizes: 2048 bytes/2048 bytes
[ 95.529724] UBIFS (ubi1:0): FS size: 19808256 bytes (18 MiB, 156 LEBs), journal size 1015809 bytes (0 MiB, 8 LEBs)
[ 95.529727] UBIFS (ubi1:0): reserved for root: 935592 bytes (913 KiB)
[ 95.529733] UBIFS (ubi1:0): media format: w4/r0 (latest is w4/r0), UUID EEB7779D-F419-4CA9-811B-831CAC7233D4, small LPT model
[ 954.264767] UBIFS error (ubi1:0 pid 756): ubifs_read_node: bad node type (255 but expected 6)
[ 954.367030] UBIFS error (ubi1:0 pid 756): ubifs_read_node: bad node at LEB 0:0, LEB mapping status 1
Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Directly return recover_head() and ubifs_leb_unmap()
instead of storing value in err and testing it.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
The commits 781c571 ("UBIFS: intialize LPT earlier") and 0980119 ("UBIFS:
fix-up free space earlier") move some initialization before marking the
master node dirty. But the modification changes the conditions of writing
master.
If unclean umount happens, ubifs may fail when mounting. But trying to
mount it will write new master nodes on the flash. This is useless but
increasing sqnum. So check need_recovery before writing master node, and
don't create new master node if filesystem needs recovery.
The behavour of the bug shows at:
http://lists.infradead.org/pipermail/linux-mtd/2015-February/057712.html
Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Reviewed-by: Ben Gardiner <ben.l.gardiner@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
When ubifs_init_security() fails, 'ui_mutex' is incorrectly
unlocked and incorrectly restores 'i_size'. Fix this.
Signed-off-by: Taesoo Kim <tsgatesv@gmail.com>
Fixes: d7f0b70d30 ("UBIFS: Add security.* XATTR support for the UBIFS")
Reviewed-by: Ben Shelton <ben.shelton@ni.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Pull UBI and UBIFS updates from Richard Weinberger:
- cleanups and bug fixes all over UBI and UBIFS
- block-mq support for UBI Block
- UBI volumes can now be renamed while they are in use
- security.* XATTR support for UBIFS
- a maintainer update
* 'for-linus-v3.20' of git://git.infradead.org/linux-ubifs:
UBI: block: Fix checking for NULL instead of IS_ERR()
UBI: block: Continue creating ubiblocks after an initialization error
UBIFS: return -EINVAL if log head is empty
UBI: Block: Explain usage of blk_rq_map_sg()
UBI: fix soft lockup in ubi_check_volume()
UBI: Fastmap: Care about the protection queue
UBIFS: add a couple of extra asserts
UBI: do propagate positive error codes up
UBI: clean-up printing helpers
UBI: extend UBI layer debug/messaging capabilities - cosmetics
UBIFS: add ubifs_err() to print error reason
UBIFS: Add security.* XATTR support for the UBIFS
UBIFS: Add xattr support for symlinks
UBI: Block: Add blk-mq support
UBI: Add initial support for scatter gather
UBI: rename_volumes: Use UBI_METAONLY
UBI: Implement UBI_METAONLY
Add myself as UBI co-maintainer
Pull backing device changes from Jens Axboe:
"This contains a cleanup of how the backing device is handled, in
preparation for a rework of the life time rules. In this part, the
most important change is to split the unrelated nommu mmap flags from
it, but also removing a backing_dev_info pointer from the
address_space (and inode), and a cleanup of other various minor bits.
Christoph did all the work here, I just fixed an oops with pages that
have a swap backing. Arnd fixed a missing export, and Oleg killed the
lustre backing_dev_info from staging. Last patch was from Al,
unexporting parts that are now no longer needed outside"
* 'for-3.20/bdi' of git://git.kernel.dk/linux-block:
Make super_blocks and sb_lock static
mtd: export new mtd_mmap_capabilities
fs: make inode_to_bdi() handle NULL inode
staging/lustre/llite: get rid of backing_dev_info
fs: remove default_backing_dev_info
fs: don't reassign dirty inodes to default_backing_dev_info
nfs: don't call bdi_unregister
ceph: remove call to bdi_unregister
fs: remove mapping->backing_dev_info
fs: export inode_to_bdi and use it in favor of mapping->backing_dev_info
nilfs2: set up s_bdi like the generic mount_bdev code
block_dev: get bdev inode bdi directly from the block device
block_dev: only write bdev inode on close
fs: introduce f_op->mmap_capabilities for nommu mmap support
fs: kill BDI_CAP_SWAP_BACKED
fs: deduplicate noop_backing_dev_info
CS node is recognized as a sign in UBIFS log replay mechanism.
Log relaying during mount should find the CS node in log head
at beginning and then replay the following uncommitted buds.
Here is a bug in log replay path: If the log head, which is
indicated by @log_lnum in mst_node, is empty, current UBIFS
replay nothing and directly mount the partition without any
warning. This action will put filesystem in an abnormal state,
e.g. space management in LPT area is incorrect to the real
space usage in main area.
We reproduced this bug by fault injection: turn log head leb
into all 0xFF. UBIFS driver mount the polluted partition
normally. But errors occur while running fs_stress on this
mount:
[89068.055183] UBI error: ubi_io_read: error -74 (ECC error) while reading 59 bytes from PEB 711:33088, read 59 bytes
[89068.179877] UBIFS error (pid 10517): ubifs_check_node: bad magic 0x101031, expected 0x6101831
[89068.179882] UBIFS error (pid 10517): ubifs_check_node: bad node at LEB 591:28992
[89068.179891] Not a node, first 24 bytes:
[89068.179892] 00000000: 31 10 10 00 37 84 64 04 10 04 00 00 00 00 00 00 20 00 00 00 02 01 00 00 1...7.d......... .......
[89068.180282] UBIFS error (pid 10517): ubifs_read_node: expected node type 2
This patch fix the problem by checking *lnum* to guarantee
the empty leb is not log head leb and return an error if the
log head leb is incorrectly empty. After this, we could catch
*log head empty* error in place.
Signed-off-by: hujianyang <hujianyang@huawei.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
... to catch possible memory corruptions.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
This patch adds ubifs_err() output to some error paths to tell the user
what's going on.
Artem: improve the messages, rename too long variable
Signed-off-by: Subodh Nijsure <snijsure@grid-net.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Ben Shelton <ben.shelton@ni.com>
Acked-by: Brad Mouring <brad.mouring@ni.com>
Acked-by: Terry Wilcox <terry.wilcox@ni.com>
Acked-by: Gratian Crisan <gratian.crisan@ni.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Artem: rename static functions so that they do not use the "ubifs_" prefix - we
only use this prefix for non-static functions.
Artem: remove few junk white-space changes in file.c
Signed-off-by: Subodh Nijsure <snijsure@grid-net.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Ben Shelton <ben.shelton@ni.com>
Acked-by: Brad Mouring <brad.mouring@ni.com>
Acked-by: Terry Wilcox <terry.wilcox@ni.com>
Acked-by: Gratian Crisan <gratian.crisan@ni.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Now that we never use the backing_dev_info pointer in struct address_space
we can simply remove it and save 4 to 8 bytes in every inode.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Reviewed-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
Since "BDI: Provide backing device capability information [try #3]" the
backing_dev_info structure also provides flags for the kind of mmap
operation available in a nommu environment, which is entirely unrelated
to it's original purpose.
Introduce a new nommu-only file operation to provide this information to
the nommu mmap code instead. Splitting this from the backing_dev_info
structure allows to remove lots of backing_dev_info instance that aren't
otherwise needed, and entirely gets rid of the concept of providing a
backing_dev_info for a character device. It also removes the need for
the mtd_inodefs filesystem.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tejun Heo <tj@kernel.org>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
The journal update function did not work for extended attributes properly,
because extended attribute inodes carry the xattr data, and the size of this
data was not taken into account.
Artem: improved commit message, amended the patch a bit.
Signed-off-by: Subodh Nijsure <snijsure@grid-net.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Ben Shelton <ben.shelton@ni.com>
Acked-by: Brad Mouring <brad.mouring@ni.com>
Acked-by: Gratian Crisan <gratian.crisan@ni.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
We forgot to free the budget in 'write_begin_slow()' when 'do_readpage()'
fails. This patch fixes the issue.
Suggested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
I found the dump messages of UBIFS_SB_NODE is not aligned. This
patch remove the extra space from the line which is retracted.
Signed-off-by: hujianyang <hujianyang@huawei.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
This assertion was only correct before UBIFS had xattr support.
Now with xattr support also a directory node can carry data
and can act as host node.
Suggested-by: Artem Bityutskiy <dedekind1@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Hu (hujianyang <hujianyang@huawei.com>) discovered an issue in the
'empty_log_bytes()' function, which calculates how many bytes are left in the
log:
"
If 'c->lhead_lnum + 1 == c->ltail_lnum' and 'c->lhead_offs == c->leb_size', 'h'
would equalent to 't' and 'empty_log_bytes()' would return 'c->log_bytes'
instead of 0.
"
At this point it is not clear what would be the consequences of this, and
whether this may lead to any problems, but this patch addresses the issue just
in case.
Cc: stable@vger.kernel.org
Tested-by: hujianyang <hujianyang@huawei.com>
Reported-by: hujianyang <hujianyang@huawei.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Hu (hujianyang@huawei.com) discovered a race condition which may lead to a
situation when UBIFS is unable to mount the file-system after an unclean
reboot. The problem is theoretical, though.
In UBIFS, we have the log, which basically a set of LEBs in a certain area. The
log has the tail and the head.
Every time user writes data to the file-system, the UBIFS journal grows, and
the log grows as well, because we append new reference nodes to the head of the
log. So the head moves forward all the time, while the log tail stays at the
same position.
At any time, the UBIFS master node points to the tail of the log. When we mount
the file-system, we scan the log, and we always start from its tail, because
this is where the master node points to. The only occasion when the tail of the
log changes is the commit operation.
The commit operation has 2 phases - "commit start" and "commit end". The former
is relatively short, and does not involve much I/O. During this phase we mostly
just build various in-memory lists of the things which have to be written to
the flash media during "commit end" phase.
During the commit start phase, what we do is we "clean" the log. Indeed, the
commit operation will index all the data in the journal, so the entire journal
"disappears", and therefore the data in the log become unneeded. So we just
move the head of the log to the next LEB, and write the CS node there. This LEB
will be the tail of the new log when the commit operation finishes.
When the "commit start" phase finishes, users may write more data to the
file-system, in parallel with the ongoing "commit end" operation. At this point
the log tail was not changed yet, it is the same as it had been before we
started the commit. The log head keeps moving forward, though.
The commit operation now needs to write the new master node, and the new master
node should point to the new log tail. After this the LEBs between the old log
tail and the new log tail can be unmapped and re-used again.
And here is the possible problem. We do 2 operations: (a) We first update the
log tail position in memory (see 'ubifs_log_end_commit()'). (b) And then we
write the master node (see the big lock of code in 'do_commit()').
But nothing prevents the log head from moving forward between (a) and (b), and
the log head may "wrap" now to the old log tail. And when the "wrap" happens,
the contends of the log tail gets erased. Now a power cut happens and we are in
trouble. We end up with the old master node pointing to the old tail, which was
erased. And replay fails because it expects the master node to point to the
correct log tail at all times.
This patch merges the abovementioned (a) and (b) operations by moving the master
node change code to the 'ubifs_log_end_commit()' function, so that it runs with
the log mutex locked, which will prevent the log from being changed benween
operations (a) and (b).
Cc: stable@vger.kernel.org # 07e19df UBIFS: remove mst_mutex
Cc: stable@vger.kernel.org
Reported-by: hujianyang <hujianyang@huawei.com>
Tested-by: hujianyang <hujianyang@huawei.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
We use a circle area to record the log nodes in ubifs. This log area
should not be overlapped. But after researching the code, I found
some conditions may lead log head wraps log ltail. Although we've
fixed the problems discovered, there may be some other issues still
left.
This patch adds assertions where lhead changes to next leb to make
sure ltail is not wrapped.
Signed-off-by: hujianyang <hujianyang@huawei.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
This reverts commit 545f7fdf6d.
Hujianyang's testing revealed that the patch is bogus.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Add an assertion which checkes that the head of the log never overlaps with the
tail of the log.
Suggested-by: hujianyang <hujianyang@huawei.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Remove the "if (c->lhead_offs == 0)" check because is unnecessary, since
at that point the log head offset is guaranteed to be zero due to the previous
operation.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
The 'mst_mutex' is not needed since because 'ubifs_write_master()' is only
called on the mount path and commit path. The mount path is sequential and
there is no parallelism, and the commit path is also serialized - there is only
one commit going on at a time.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Fix checkpatch warnings:
"WARNING: Prefer seq_puts to seq_printf"
Andrew Morton wrote:
"
- puts is presumably faster
- puts doesn't go rogue if you accidentally pass it a "%".
- this patch actually made fs/ubifs/super.o 12 bytes smaller.
Perhaps because seq_printf() is a varargs function, forcing the
caller to pass args on the stack instead of in registers.
"
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
No grouped argument in drop_last_node.
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
In the end of 'create_default_filesystem()' we need to check
the return value of 'ubifs_write_node()' to ensure that we have
successfully written the 'cs_node'.
Signed-off-by: hujianyang <hujianyang@huawei.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Randy Dunlap pointed that we should use "scanned" instead of "scaned". This
patch makes the correction.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
This patch fixes some comments about return type.
Signed-off-by: Seunghun Lee <waydi1@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>