For all child objects, creation comes through mkdir(2), so duplicate names
are prevented.
Subsystems, though, are registered by client drivers at init_module()/__init
time. This patch prevents duplicate subsystem names.
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
* 'fixes' of git://git.linux-nfs.org/pub/linux/nfs-2.6:
NFS: Fix nfs_page use after free issues in fs/nfs/write.c
NFSv4: Fix incorrect semaphore release in _nfs4_do_open()
NFS: Fix Oopsable condition in nfs_readpage_sync()
* git://git.infradead.org/mtd-2.6:
[MTD] Use SEEK_{SET,CUR,END} instead of hardcoded values in mtdchar lseek()
MTD: Fix bug in fixup_convert_atmel_pri
[JFFS2][SUMMARY] Fix a summary collecting bug.
[PATCH] [MTD] DEVICES: Fill more device IDs in the structure of m25p80
MTD: Add lock/unlock operations for Atmel AT49BV6416
MTD: Convert Atmel PRI information to AMD format
fs/jffs2/xattr.c: remove dead code
[PATCH] [MTD] Maps: Add dependency on alternate probe methods to physmap
[PATCH] MTD: Add Macronix MX29F040 to JEDEC
[MTD] Fixes of performance and stability issues in CFI driver.
block2mtd.c: Make kernel boot command line arguments work (try 4)
[MTD NAND] Fix lookup error in nand_get_flash_type()
remove #error on !PCI from pmc551.c
MTD: [NAND] Fix the sharpsl driver after breakage from a core conversion
[MTD] NAND: OOB buffer offset fixups
make fs/jffs2/nodelist.c:jffs2_obsolete_node_frag() static
[PATCH] [MTD] NAND: fix dead URL in Kconfig
Fix a performance degradation introduced in 2.6.17. (30% degradation
running dbench with 16 threads)
Commit 21730eed11, which claims to make
EXT2_DEBUG work again, moves the taking of the kernel lock out of
debug-only code in ext2_count_free_inodes and ext2_count_free_blocks and
into ext2_statfs.
The same problem was fixed in ext3 by removing the lock completely (commit
5b11687924)
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In some special case (padding because of sync or umount) it can be possible
that summary information is not fit to the end of the erase block. In
these cases the collecting of summary is disabled for this erase block.
The problem was that this was not respected by jffs2_sum_add_kvec(). This
patch fix this bug.
Signed-off-by: Ferenc Havasi <havasi@inf.u-szeged.hu>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
ext3-get-blocks support caused ~20% degrade in Sequential read
performance (tiobench). Problem is with marking the buffer boundary
so IO can be submitted right away. Here is the patch to fix it.
2.6.18-rc6:
-----------
# ./iotest
1048576+0 records in
1048576+0 records out
4294967296 bytes (4.3 GB) copied, 75.2726 seconds, 57.1 MB/s
real 1m15.285s
user 0m0.276s
sys 0m3.884s
2.6.18-rc6 + fix:
-----------------
[root@elm3a241 ~]# ./iotest
1048576+0 records in
1048576+0 records out
4294967296 bytes (4.3 GB) copied, 62.9356 seconds, 68.2 MB/s
The boundary block check in ext3_get_blocks_handle needs to be adjusted
against the count of blocks mapped in this call, now that it can map
more than one block.
Signed-off-by: Suparna Bhattacharya <suparna@in.ibm.com>
Tested-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Inodes earlier than the 'first' inode (e.g. journal, resize) should be
rejected early - except the root inode. Also inode numbers that are too
big should be rejected early.
[akpm@osdl.org: cleanup]
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This prevents bad inode numbers from triggering errors in ext2_get_inode.
[akpm@osdl.org: speedup, cleanup]
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In some special case (padding because of sync
or umount) it can be possible that summary
information is not fit to the end of the erase
block. In these cases the collecting of summary
is disabled for this erase block.
The problem was that this was not respected
by jffs2_sum_add_kvec(). This patch fix this
bug.
From: Zoltan Sogor <weth@inf.u-szeged.hu>
Signed-off-by: Ferenc Havasi <havasi@inf.u-szeged.hu>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
* git://oss.sgi.com:8090/xfs/xfs-2.6:
[XFS] Fix a bad pointer dereference in the quota statvfs handling.
[XFS] Fix xfs_splice_write() so appended data gets to disk.
[XFS] Fix ABBA deadlock between i_mutex and iolock. Avoid calling
[XFS] Prevent free space oversubscription and xfssyncd looping.
The logic in nfs_direct_read_schedule and nfs_direct_write_schedule can
allow data->npages to be one larger than rpages. This causes a page
pointer to be written beyond the end of the pagevec in nfs_read_data (or
nfs_write_data).
Fix this by making nfs_(read|write)_alloc() calculate the size of the
pagevec array, and initialise data->npages.
Also get rid of the redundant argument to nfs_commit_alloc().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It has been reported that ext3_getblk() is not doing the right thing and
triggering following WARN():
BUG: warning at fs/ext3/inode.c:1016/ext3_getblk()
<c01c5140> ext3_getblk+0x98/0x2a6 <c03b2806> md_wakeup_thread+0x26/0x2a
<c01c536d> ext3_bread+0x1f/0x88 <c01cedf9> ext3_quota_read+0x136/0x1ae
<c018b683> v1_read_dqblk+0x61/0xac <c0188f32> dquot_acquire+0xf6/0x107
<c01ceaba> ext3_acquire_dquot+0x46/0x68 <c01897d4> dqget+0x155/0x1e7
<c018a97b> dquot_transfer+0x3e0/0x3e9 <c016fe52> dput+0x23/0x13e
<c01c7986> ext3_setattr+0xc3/0x240 <c0120f66> current_fs_time+0x52/0x6a
<c017320e> notify_change+0x2bd/0x30d <c0159246> chown_common+0x9c/0xc5
<c02a222c> strncpy_from_user+0x3b/0x68 <c0167fe6> do_path_lookup+0xdf/0x266
<c016841b> __user_walk_fd+0x44/0x5a <c01592b9> sys_chown+0x4a/0x55
<c015a43c> vfs_write+0xe7/0x13c <c01695d4> sys_mkdir+0x1f/0x23
<c0102a97> syscall_call+0x7/0xb
Looking at the code, it looks like it's not handle HOLE correctly. It ends
up returning -EIO. Here is the patch to fix it.
If we really want to be paranoid, we can allow return values 0 (HOLE), 1
(we asked for one block) and return -EIO for more than 1 block. But I
really don't see a reason for doing it - all we need is the block# here.
(doesn't matter how many blocks are mapped).
ext3_get_blocks_handle() returns number of blocks it mapped. It returns 0
in case of HOLE. ext3_getblk() should handle HOLE properly (currently its
dumping warning stack and returning -EIO).
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Acked-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
xfs_splice_write() failed to update the on disk inode size when extending
the so when the file was closed the range extended by splice was truncated
off. Hence any region of a file written to by splice would end up as a
hole full of zeros.
SGI-PV: 955939
SGI-Modid: xfs-linux-melb:xfs-kern:26920a
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: David Chatterton <chatz@sgi.com>
__blockdev_direct_IO for the DIO_OWN_LOCKING case for direct I/O reads
since it drops and reacquires the i_mutex while holding the iolock and
this violates the locking order.
SGI-PV: 955696
SGI-Modid: xfs-linux-melb:xfs-kern:26898a
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: David Chatterton <chatz@sgi.com>
The fix for recent ENOSPC deadlocks introduced certain limitations on
allocations. The fix could cause xfssyncd to loop endlessly if we did not
leave some space free for the allocator to work correctly. Basically, we
needed to ensure that we had at least 4 blocks free for an AG free list
and a block for the inode bmap btree at all times.
However, this did not take into account the fact that each AG has a free
list that needs 4 blocks. Hence any filesystem with more than one AG could
cause oversubscription of free space and make xfssyncd spin forever trying
to allocate space needed for AG freelists that was not available in the
AG.
The following patch reserves space for the free lists in all AGs plus the
inode bmap btree which prevents oversubscription. It also prevents those
blocks from being reported as free space (as they can never be used) and
makes the SMP in-core superblock accounting code and the reserved block
ioctl respect this requirement.
SGI-PV: 955674
SGI-Modid: xfs-linux-melb:xfs-kern:26894a
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: David Chatterton <chatz@sgi.com>
CIFS had one path in which dentry was instantiated before the corresponding
inode metadata was filled in.
Fixes Redhat bugzilla bug #163493
Signed-off-by: Steve French <sfrench@us.ibm.com>
Acked-by: Eric Paris <eparis@redhat.com>
Acked-by: Dave Kleikamp <shaggy@austin.ibm.com>
Adds kernel-doc for alloc_super() type in fs/super.c.
Signed-off-by: Henrik Kretzschmar <henne@nachtwindheim.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Missed a place where I forgot to convert kfree() to kmem_cache_free() as
part of jbd-manage-its-own-slab changes.
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
conversion.
Since bma.conv is a char and XFS_BMAPI_CONVERT is 0x1000, bma.conv was
always assigned zero. Spotted by the GNU C compiler (SVN version).
SGI-PV: 947312
SGI-Modid: xfs-linux-melb:xfs-kern:26887a
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Nathan Scott <nathans@sgi.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
[CIFS] Do not send Query All EAs SMB when mount option nouser_xattr
[CIFS] endian errors in lanman protocol support
[CIFS] Fix oops in cifs_close due to unitialized lock sem and list in
[CIFS] Fix oops when negotiating lanman and no password specified
[CIFS]
[CIFS] Allow cifsd to suspend if connection is lost
[CIFS] Make midState usage more consistent
[CIFS] spinlock protect read of last srv response time in timeout path
[CIFS] Do not time out posix brl requests when using new posix setfileinfo
None of the other /proc/meminfo lines have a space in the identifier. This
post-2.6.17 addition has the potential to break existing parsers, so use an
underscore instead (like Committed_AS).
Cc: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This fixes the locking error noticed by lockdep:
=============================================
[ INFO: possible recursive locking detected ]
---------------------------------------------
init/1 is trying to acquire lock:
(&sighand->siglock){....}, at: [<c047a78a>] flush_old_exec+0x3ae/0x859
but task is already holding lock:
(&sighand->siglock){....}, at: [<c047a77a>] flush_old_exec+0x39e/0x859
other info that might help us debug this:
2 locks held by init/1:
#0: (tasklist_lock){..--}, at: [<c047a76a>] flush_old_exec+0x38e/0x859
#1: (&sighand->siglock){....}, at: [<c047a77a>] flush_old_exec+0x39e/0x859
stack backtrace:
[<c04051e1>] show_trace_log_lvl+0x54/0xfd
[<c040579d>] show_trace+0xd/0x10
[<c04058b6>] dump_stack+0x19/0x1b
[<c043b33a>] __lock_acquire+0x773/0x997
[<c043bacf>] lock_acquire+0x4b/0x6c
[<c060630b>] _spin_lock+0x19/0x28
[<c047a78a>] flush_old_exec+0x3ae/0x859
[<c0498053>] load_elf_binary+0x4aa/0x1628
[<c0479cab>] search_binary_handler+0xa7/0x24e
[<c047b577>] do_execve+0x15b/0x1f9
[<c04022b4>] sys_execve+0x29/0x4d
[<c0403faf>] syscall_call+0x7/0xb
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
reiserfs seems to have another locking level layer for the i_mutex due to the
xattrs-are-a-directory thing.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
JBD currently allocates commit and frozen buffers from slabs. With
CONFIG_SLAB_DEBUG, its possible for an allocation to cross the page
boundary causing IO problems.
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=200127
So, instead of allocating these from regular slabs - manage allocation from
its own slabs and disable slab debug for these slabs.
[akpm@osdl.org: cleanups]
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix two compile failures in eventpoll.c code which would happen if
DEBUG_EPOLL is bigger than zero.
Signed-off-by: Masoud Sharbiani <masouds@google.com>
Cc: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
1) When we allocated last fragment in ufs_truncate, we read page, check
if block mapped to address, and if not trying to allocate it. This is
wrong behaviour, fragment may be NOT allocated, but mapped, this
happened because of "block map" function not checked allocated fragment
or not, it just take address of the first fragment in the block, add
offset of fragment and return result, this is correct behaviour in
almost all situation except call from ufs_truncate.
2) Almost all implementation of UFS, which I can investigate have such
"defect": if you have full disk, and try truncate file, for example 3GB
to 2MB, and have hole in this region, truncate return -ENOSPC. I tried
evade from this problem, but "block allocation" algorithm is tied to
right value of i_lastfrag, and fix of this corner case may slow down of
ordinaries scenarios, so this patch makes behavior of "truncate"
operations similar to what other UFS implementations do.
Signed-off-by: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
On UFS, this scenario:
open(O_TRUNC)
lseek(1024 * 1024 * 80)
write("A")
lseek(1024 * 2)
write("A")
may cause access to invalid address.
This happened because of "goal" is calculated in wrong way in block
allocation path, as I see this problem exists also in 2.4.
We use construction like this i_data[lastfrag], i_data array of pointers to
direct blocks, indirect and so on, it has ceratain size ~20 elements, and
lastfrag may have value for example 40000.
Also this patch fixes related to handling such scenario issues, wrong
zeroing metadata, in case of block(not fragment) allocation, and wrong goal
calculation, when we allocate block
Signed-off-by: Evgeniy Dushistov <dushistov@mail.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
To handle the earlier bogus ENOSPC error caused by filesystem full of block
reservation, current code falls back to non block reservation, starts to
allocate block(s) from the goal allocation block group as if there is no
block reservation.
Current code needs to re-load the corresponding block group descriptor for
the initial goal block group in this case. The patch fixes this.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Mounting an ext2 filesystem with zero s_inodes_per_group will cause a
divide error.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Mounting a (corrupt) minix filesystem with zero s_zmap_blocks
gives a spectacular crash on my 2.6.17.8 system, no doubt
because minix/inode.c does an unconditional
minix_set_bit(0,sbi->s_zmap[0]->b_data);
[akpm@osdl.org: make labels conistent while we're there]
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
On Wed, 2006-08-09 at 07:57 +0200, Rolf Eike Beer wrote:
> =============================================
> [ INFO: possible recursive locking detected ]
> ---------------------------------------------
> parted/7929 is trying to acquire lock:
> (&bdev->bd_mutex){--..}, at: [<c105eb8d>] __blkdev_put+0x1e/0x13c
>
> but task is already holding lock:
> (&bdev->bd_mutex){--..}, at: [<c105eec6>] do_open+0x72/0x3a8
>
> other info that might help us debug this:
> 1 lock held by parted/7929:
> #0: (&bdev->bd_mutex){--..}, at: [<c105eec6>] do_open+0x72/0x3a8
> stack backtrace:
> [<c1003aad>] show_trace_log_lvl+0x58/0x15b
> [<c100495f>] show_trace+0xd/0x10
> [<c1004979>] dump_stack+0x17/0x1a
> [<c102dee5>] __lock_acquire+0x753/0x99c
> [<c102e3b0>] lock_acquire+0x4a/0x6a
> [<c1204501>] mutex_lock_nested+0xc8/0x20c
> [<c105eb8d>] __blkdev_put+0x1e/0x13c
> [<c105ecc4>] blkdev_put+0xa/0xc
> [<c105f18a>] do_open+0x336/0x3a8
> [<c105f21b>] blkdev_open+0x1f/0x4c
> [<c1057b40>] __dentry_open+0xc7/0x1aa
> [<c1057c91>] nameidata_to_filp+0x1c/0x2e
> [<c1057cd1>] do_filp_open+0x2e/0x35
> [<c1057dd7>] do_sys_open+0x38/0x68
> [<c1057e33>] sys_open+0x16/0x18
> [<c1002845>] sysenter_past_esp+0x56/0x8d
OK, I'm having a look here; its all new to me so bear with me.
blkdev_open() calls
do_open(bdev, ...,BD_MUTEX_NORMAL) and takes
mutex_lock_nested(&bdev->bd_mutex, BD_MUTEX_NORMAL)
then something fails, and we're thrown to:
out_first: where
if (bdev != bdev->bd_contains)
blkdev_put(bdev->bd_contains) which is
__blkdev_put(bdev->bd_contains, BD_MUTEX_NORMAL) which does
mutex_lock_nested(&bdev->bd_contains->bd_mutex, BD_MUTEX_NORMAL) <--- lockdep trigger
When going to out_first, dbev->bd_contains is either bdev or whole, and
since we take the branch it must be whole. So it seems to me the
following patch would be the right one:
[akpm@osdl.org: compile fix]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The current sun disklabel code uses a signed int for the sector count.
When partitions larger than 1 TB are used, the cast to a sector_t causes
the partition sizes to be invalid:
# cat /proc/paritions | grep sdan
66 112 2146435072 sdan
66 115 9223372036853660736 sdan3
66 120 9223372036853660736 sdan8
This patch switches the sector count to an unsigned int to fix this.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The check in open_exec() for inode->i_mode & 0111 has been made
redundant by the fix to permission().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from 1d3741c5d991686699f100b65b9956f7ee7ae0ae commit)
The check in prepare_binfmt() for inode->i_mode & 0111 is redundant,
since open_exec() will already have done that.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from 822dec482ced07af32c378cd936d77345786572b commit)
Currently, the access() call will return incorrect information on NFS if
there exists an ACL that grants execute access to the user on a regular
file. The reason the information is incorrect is that the VFS overrides
this execute access in open_exec() by checking (inode->i_mode & 0111).
This patch propagates the VFS execute bit check back into the generic
permission() call.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from 64cbae98848c4c99851cb0a405f0b4982cd76c1e commit)
This is needed in order to handle any NFS4ERR_DELAY errors that might be
returned by the server. It also ensures that we map the NFSv4 errors before
they are returned to userland.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from 71c12b3f0abc7501f6ed231a6d17bc9c05a238dc commit)
Check the bounds of length specifiers more thoroughly in the XDR decoding of
NFS4 readdir reply data.
Currently, if the server returns a bitmap or attr length that causes the
current decode point pointer to wrap, this could go undetected (consider a
small "negative" length on a 32-bit machine).
Also add a check into the main XDR decode handler to make sure that the amount
of data is a multiple of four bytes (as specified by RFC-1014). This makes
sure that we can do u32* pointer subtraction in the NFS client without risking
an undefined result (the result is undefined if the pointers are not correctly
aligned with respect to one another).
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from 5861fddd64a7eaf7e8b1a9997455a24e7f688092 commit)
The problem is that we may be caching writes that would extend the file and
create a hole in the region that we are reading. In this case, we need to
detect the eof from the server, ensure that we zero out the pages that
are part of the hole and mark them as up to date.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from 856b603b01b99146918c093969b6cb1b1b0f1c01 commit)
nlm_traverse_files() is not allowed to hold the nlm_file_mutex while calling
nlm_inspect file, since it may end up calling nlm_release_file() when
releaseing the blocks.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from e558d3cde986e04f68afe8c790ad68ef4b94587a commit)
rpc_unlink() and rpc_rmdir() will dput the dentry reference for you.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from a05a57effa71a1f67ccbfc52335c10c8b85f3f6a commit)
I'm trying to speeding up mkdir(2) for network file systems. A typical
mkdir(2) calls two inode_operations: lookup and mkdir. The lookup
operation would fail with ENOENT in common case. I think it is unnecessary
because the subsequent mkdir operation can check it. In case of creat(2),
lookup operation is called with the LOOKUP_CREATE flag, so individual
filesystem can omit real lookup. e.g. nfs_lookup().
Here is a sample patch which uses LOOKUP_CREATE and O_EXCL on mkdir,
symlink and mknod. This uses the gadget for creat(2).
And here is the result of a benchmark on NFSv3.
mkdir(2) 10,000 times:
original 50.5 sec
patched 29.0 sec
Signed-off-by: ASANO Masahiro <masano@tnes.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from fab7bf44449b29f9d5572a5dd8adcf7c91d5bf0f commit)
nfs_wb_page() waits on request completion and, as a result, is not safe to be
called from nfs_release_page() invoked by VM scanner as part of GFP_NOFS
allocation. Fix possible deadlock by analyzing gfp mask and refusing to
release page if __GFP_FS is not set.
Signed-off-by: Nikita Danilov <danilov@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from 374d969debfb290bafcb41d28918dc6f7e43ce31 commit)