Age | Commit message (Collapse) | Author |
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nfs_do_filldir() must always free desc->page when it is done, otherwise
we end up leaking the page.
Also remove unused variable 'dentry'.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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Some servers are known to be buggy w.r.t. this. Deal with them...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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Overflowing the buffer in the readdir ->decode_dirent() should not lead to
a fatal error, but rather to an attempt to reread the record in question.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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When an application opens a file with O_DIRECT flag, if the size of
the data that is written is equal to wsize, the client sends a
WRITE RPC with stable flag set to UNSTABLE followed by a single
COMMIT RPC rather than sending a single WRITE RPC with the stable
flag set to FILE_SYNC. This a bug.
Patch to fix this.
Signed-off-by: Arun R Bharadwaj <arun@linux.vnet.ibm.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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If we fail to find a pointer in the radix tree, don't try
to deref the NULL one we do have.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
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Everybody who calls btrfs_add_nondir just passes in the dentry of the new file
and then dereference dentry->d_parent->d_inode, but everybody who calls
btrfs_add_nondir() are already passed the parent's inode. So instead of
dereferencing dentry->d_parent, just make btrfs_add_nondir take the dir inode as
an argument and pass that along so we don't have to worry about d_parent.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
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Since we walk up the path logging all of the parts of the inode's path, we need
to hold i_mutex to make sure that the inode is not renamed while we're logging
everything. btrfs_log_dentry_safe does dget_parent and all of that jazz, but we
may get unexpected results if the rename changes the inode's location while
we're higher up the path logging those dentries, so do this for safety reasons.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
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There are lots of places where we do dentry->d_parent->d_inode without holding
the dentry->d_lock. This could cause problems with rename. So instead we need
to use dget_parent() and hold the reference to the parent as long as we are
going to use it's inode and then dput it at the end.
Signed-off-by: Josef Bacik <josef@redhat.com>
Cc: raven@themaw.net
Signed-off-by: Chris Mason <chris.mason@oracle.com>
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When creating new inodes we don't setup inode->i_generation. So if we generate
an fh with a newly created inode we save the generation of 0, but if we flush
the inode to disk and have to read it back when getting the inode on the server
we'll have the right i_generation, so gens wont match and we get ESTALE. This
patch properly sets inode->i_generation when we create the new inode and now I'm
no longer getting ESTALE. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
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People kept reporting NFS issues, specifically getting ESTALE alot. I figured
out how to reproduce the problem
SERVER
mkfs.btrfs /dev/sda1
mount /dev/sda1 /mnt/btrfs-test
<add /mnt/btrfs-test to /etc/exports>
btrfs subvol create /mnt/btrfs-test/foo
service nfs start
CLIENT
mount server:/mnt/btrfs /mnt/test
cd /mnt/test/foo
ls
SERVER
echo 3 > /proc/sys/vm/drop_caches
CLIENT
ls <-- get an ESTALE here
This is because the standard way to lookup a name in nfsd is to use readdir, and
what it does is do a readdir on the parent directory looking for the inode of
the child. So in this case the parent being / and the child being foo. Well
subvols all have the same inode number, so doing a readdir of / looking for
inode 256 will return '.', which obviously doesn't match foo. So instead we
need to have our own .get_name so that we can find the right name.
Our .get_name will either lookup the inode backref or the root backref,
whichever we're looking for, and return the name we find. Running the above
reproducer with this patch results in everything acting the way its supposed to.
Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
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Fixes these sparse warnings:
fs/btrfs/ctree.h:811:17: error: dubious one-bit signed bitfield
fs/btrfs/ctree.h:812:20: error: dubious one-bit signed bitfield
fs/btrfs/ctree.h:813:19: error: dubious one-bit signed bitfield
Signed-off-by: Mariusz Kozlowski <mk@lab.zgora.pl>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
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Symlinks and files of other types show different device numbers, though
they are on the same partition:
$ touch tmp; ln -s tmp tmp2; stat tmp tmp2
File: `tmp'
Size: 0 Blocks: 0 IO Block: 4096 regular empty file
Device: 15h/21d Inode: 984027 Links: 1
--- snip ---
File: `tmp2' -> `tmp'
Size: 3 Blocks: 0 IO Block: 4096 symbolic link
Device: 13h/19d Inode: 984028 Links: 1
Reported-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
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Set src_offset = 0, src_length = 20K, dest_offset = 20K. And the
original filesize of the dest file 'file2' is 30K:
# ls -l /mnt/file2
-rw-r--r-- 1 root root 30720 Nov 18 16:42 /mnt/file2
Now clone file1 to file2, the dest file should be 40K, but it
still shows 30K:
# ls -l /mnt/file2
-rw-r--r-- 1 root root 30720 Nov 18 16:42 /mnt/file2
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
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We've done the check for src_offset and src_length, and We should
also check dest_offset, otherwise we'll corrupt the destination
file:
(After cloning file1 to file2 with unaligned dest_offset)
# cat /mnt/file2
cat: /mnt/file2: Input/output error
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
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When I added the clear_cache option I screwed up and took the break out of
the space_cache case statement, so whenever you mount with space_cache you also
get clear_cache, which does you no good if you say set space_cache in fstab so
it always gets set. This patch adds the break back in properly.
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
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'unused' calculated with wrong sign in reserve_metadata_bytes().
This might have lead to unwanted over-reservations.
Signed-off-by: Arne Jansen <sensille@gmx.net>
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
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btrfs paniced when we write >64KB data by direct IO at one time.
Reproduce steps:
# mkfs.btrfs /dev/sda5 /dev/sda6
# mount /dev/sda5 /mnt
# dd if=/dev/zero of=/mnt/tmpfile bs=100K count=1 oflag=direct
Then btrfs paniced:
mapping failed logical 1103155200 bio len 69632 len 12288
------------[ cut here ]------------
kernel BUG at fs/btrfs/volumes.c:3010!
[SNIP]
Pid: 1992, comm: btrfs-worker-0 Not tainted 2.6.37-rc1 #1 D2399/PRIMERGY
RIP: 0010:[<ffffffffa03d1462>] [<ffffffffa03d1462>] btrfs_map_bio+0x202/0x210 [btrfs]
[SNIP]
Call Trace:
[<ffffffffa03ab3eb>] __btrfs_submit_bio_done+0x1b/0x20 [btrfs]
[<ffffffffa03a35ff>] run_one_async_done+0x9f/0xb0 [btrfs]
[<ffffffffa03d3d20>] run_ordered_completions+0x80/0xc0 [btrfs]
[<ffffffffa03d45a4>] worker_loop+0x154/0x5f0 [btrfs]
[<ffffffffa03d4450>] ? worker_loop+0x0/0x5f0 [btrfs]
[<ffffffffa03d4450>] ? worker_loop+0x0/0x5f0 [btrfs]
[<ffffffff81083216>] kthread+0x96/0xa0
[<ffffffff8100cec4>] kernel_thread_helper+0x4/0x10
[<ffffffff81083180>] ? kthread+0x0/0xa0
[<ffffffff8100cec0>] ? kernel_thread_helper+0x0/0x10
We fix this problem by splitting bios when we submit bios.
Reported-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Tested-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
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extent_bio_alloc() and compressed_bio_alloc() are similar, cleanup
similar source code.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
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bio_endio() will free dip and dip->csums, so dip and dip->csums twice will
be freed twice. Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
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Migrate page will directly call the btrfs btree writepage function,
which isn't actually allowed.
Our writepage assumes that you have locked the extent_buffer and
flagged the block as written. Without doing these steps, we can
corrupt metadata blocks.
A later commit will remove the btree writepage function since
it is really only safely used internally by btrfs. We
use writepages for everything else.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: Add EXT4_IOC_TRIM ioctl to handle batched discard
fs: Do not dispatch FITRIM through separate super_operation
ext4: ext4_fill_super shouldn't return 0 on corruption
jbd2: fix /proc/fs/jbd2/<dev> when using an external journal
ext4: missing unlock in ext4_clear_request_list()
ext4: fix setting random pages PageUptodate
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Filesystem independent ioctl was rejected as not common enough to be in
core vfs ioctl. Since we still need to access to this functionality this
commit adds ext4 specific ioctl EXT4_IOC_TRIM to dispatch
ext4_trim_fs().
It takes fstrim_range structure as an argument. fstrim_range is definec in
the include/linux/fs.h and its definition is as follows.
struct fstrim_range {
__u64 start;
__u64 len;
__u64 minlen;
}
start - first Byte to trim
len - number of Bytes to trim from start
minlen - minimum extent length to trim, free extents shorter than this
number of Bytes will be ignored. This will be rounded up to fs
block size.
After the FITRIM is done, the number of actually discarded Bytes is stored
in fstrim_range.len to give the user better insight on how much storage
space has been really released for wear-leveling.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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There was concern that FITRIM ioctl is not common enough to be included
in core vfs ioctl, as Christoph Hellwig pointed out there's no real point
in dispatching this out to a separate vector instead of just through
->ioctl.
So this commit removes ioctl_fstrim() from vfs ioctl and trim_fs
from super_operation structure.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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create_session
At the latest kernel(2.6.37-rc1), server just initialize the forechannel
at init_forechannel_attrs, but don't reflect it to reply.
After initialize the session success, we should copy the forechannel info
to nfsd4_create_session struct.
Reviewed-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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When server gets drc mem fail, it should reply error to client.
Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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We're refusing to support a mandatory features of 4.1, so serverfault
seems the better error; see e.g.:
http://www.ietf.org/mail-archive/web/nfsv4/current/msg07638.html
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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According to RFC, the argument of ssv_sp_parms4 is:
struct ssv_sp_parms4 {
state_protect_ops4 ssp_ops;
sec_oid4 ssp_hash_algs<>;
sec_oid4 ssp_encr_algs<>;
uint32_t ssp_window;
uint32_t ssp_num_gss_handles;
};
If client send a exchange_id with SP4_SSV, server cann't decode
the SP4_SSV's ssp_hash_algs and ssp_encr_algs arguments correctly.
Because the kernel treat the two arguments as a signal
sec_oid4 struct, but should be a set of sec_oid4 struct.
Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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The original code would oops if this were called from nfsd4_setattr()
because "filpp" is NULL.
(Note this case is currently impossible, as long as we only give out
read delegations.)
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
ceph: fix readdir EOVERFLOW on 32-bit archs
ceph: fix frag offset for non-leftmost frags
ceph: fix dangling pointer
ceph: explicitly specify page alignment in network messages
ceph: make page alignment explicit in osd interface
ceph: fix comment, remove extraneous args
ceph: fix update of ctime from MDS
ceph: fix version check on racing inode updates
ceph: fix uid/gid on resent mds requests
ceph: fix rdcache_gen usage and invalidate
ceph: re-request max_size if cap auth changes
ceph: only let auth caps update max_size
ceph: fix open for write on clustered mds
ceph: fix bad pointer dereference in ceph_fill_trace
ceph: fix small seq message skipping
Revert "ceph: update issue_seq on cap grant"
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At the start of ext4_fill_super, ret is set to -EINVAL, and any failure path
out of that function returns ret. However, the generic_check_addressable
clause sets ret = 0 (if it passes), which means that a subsequent failure (e.g.
a group checksum error) returns 0 even though the mount should fail. This
causes vfs_kern_mount in turn to think that the mount succeeded, leading to an
oops.
A simple fix is to avoid using ret for the generic_check_addressable check,
which was last changed in commit 30ca22c70e3ef0a96ff84de69cd7e8561b416cb2.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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Userland programs using the quotactl() syscall assume limit/warn/usage
block counts in 512b basic blocks which were instead being read/written
in fs blocksize in gfs2. With this patch, gfs2 correctly interacts with
the syscall using 512b blocks.
Signed-off-by: Abhi Das <adas@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
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If ocfs2_live_connection_list is empty, ocfs2_connection_find() will return
a pointer to the LIST_HEAD, cast as a ocfs2_live_connection. This can cause
an oops when ocfs2_control_send_down() dereferences c->oc_conn:
Call Trace:
[<ffffffffa00c2a3c>] ocfs2_control_message+0x28c/0x2b0 [ocfs2_stack_user]
[<ffffffffa00c2a95>] ocfs2_control_write+0x35/0xb0 [ocfs2_stack_user]
[<ffffffff81143a88>] vfs_write+0xb8/0x1a0
[<ffffffff8155cc13>] ? do_page_fault+0x153/0x3b0
[<ffffffff811442f1>] sys_write+0x51/0x80
[<ffffffff810121b2>] system_call_fastpath+0x16/0x1b
Fix by explicitly returning NULL if no match is found.
Signed-off-by: dann frazier <dann.frazier@canonical.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
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Commit 1c66b360fe262 (Change some lock status member in ocfs2_lock_res
to char.) states that these fields need to be signed due to comparision
to -1, but only changed the type from unsigned char to char. However, it
is a compiler option if char is a signed or unsigned type. Change these
fields to signed char so the code will work with all compilers.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
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I suddenly hit the problem during 2.6.37-rc1 regression test, which was
introduced by commit '5e98d492406818e6a94c0ba54c61f59d40cefa4a'(Track
negative entries v3), following scenario reproduces the issue easily:
Node A Node B
================ ============
$touch testfile
$ls testfile
$rm -rf testfile
$touch testfile
$ls testfile
ls: cannot access testfile: No such file or directory
This patch stops tracking the dentry which was negativated by a inode deletion,
so as to force the revaliation in next lookup, in case we'll touch the inode
again in the same node.
It didn't hurt the performance of multiple lookup for none-existed files anyway,
while regresses a bit in the first try after a file deletion.
Signed-off-by: Tristan Ye <tristan.ye@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
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Stanse found that o2hb_heartbeat_group_make_item leaks some memory on
fail paths. Fix the paths by adding a new label and jump there.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <joel.becker@oracle.com>
Cc: ocfs2-devel@oss.oracle.com
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Joel Becker <joel.becker@oracle.com>
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coccinelle check scripts/coccinelle/locks/call_kern.cocci found that
in fs/ocfs2/dlm/dlmdomain.c an allocation with GFP_KERNEL is done
with locks held:
dlm_query_region_handler
spin_lock(dlm_domain_lock)
dlm_match_regions
kmalloc(GFP_KERNEL)
Change it to GFP_ATOMIC.
Signed-off-by: David Sterba <dsterba@suse.cz>
CC: Joel Becker <joel.becker@oracle.com>
CC: Mark Fasheh <mfasheh@suse.com>
CC: ocfs2-devel@oss.oracle.com
--
Exists in v2.6.37-rc1 and current linux-next.
Signed-off-by: Joel Becker <joel.becker@oracle.com>
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One of the readdir filldir_t callers was passing the raw ceph 64-bit ino
instead of the hashed 32-bit one, producing an EOVERFLOW in the filler
callback. Fix this by calling the ceph_vino_to_ino() helper to do the
conversion.
Reported-by: Jan Smets <jan.smets@alcatel-lucent.com>
Tested-by: Jan Smets <jan.smets@alcatel-lucent.com>
Signed-off-by: Sage Weil <sage@newdream.net>
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In jbd2_journal_init_dev(), we need make sure the journal structure is
fully initialzied before calling jbd2_stats_proc_init().
Reviewed-by: Andreas Dilger <andreas.dilger@oracle.com>
Signed-off-by: yangsheng <sheng.yang@oracle.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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If the the li_request_list was empty then it returned with the lock
held. Instead of adding a "goto unlock" I just removed that special
case and let it go past the empty list_for_each_safe().
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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ext4_end_bio calls put_page and kmem_cache_free before calling
SetPageUpdate(). This can result in setting the PageUptodate bit on
random pages and causes the following BUG:
BUG: Bad page state in process rm pfn:52e54
page:ffffea0001222260 count:0 mapcount:0 mapping: (null) index:0x0
arch kernel: page flags: 0x4000000000000008(uptodate)
Fix the problem by moving put_io_page() after the SetPageUpdate() call.
Thanks to Hugh Dickins for analyzing this problem.
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Tested-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
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Lock_kernel is gone from the code, so the comments should be updated,
too. nfsd now uses lock_flocks instead of lock_kernel to protect
against posix file locks.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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The big kernel lock has been removed from all these files at some point,
leaving only the #include.
Remove this too as a cleanup.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Strings allocated via kmemdup() in nfs_readdir_make_qstr() are
referenced from the nfs_cache_array which is stored in a page cache
page. Kmemleak does not scan such pages and it reports several false
positives. This patch annotates the string->name pointer so that
kmemleak does not consider it a real leak.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Bryan Schumaker <bjschuma@netapp.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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Fix up the issue that array->eof_index needs to be able to be set
even if array->size == 0.
Ensure that we catch all important memory allocation error conditions
and/or kmap() failures.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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EISDIR"
This reverts commit 80e60639f1b7c121a7fea53920c5a4b94009361a.
This change requires further fixes to ensure that the open doesn't
succeed if the lookup later results in a regular file being created.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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Trying to mount NFS (root partition in my case) fails if CONFIG_NFS_V3
is not selected. nfs_validate_mount_data() returns EPROTONOSUPPORT,
because of this check:
#ifndef CONFIG_NFS_V3
if (args->version == 3)
goto out_v3_not_compiled;
#endif /* !CONFIG_NFS_V3 */
and args->version was always initialized to 3.
It was working in 2.6.36
Signed-off-by: Paulius Zaleckas <paulius.zaleckas@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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Nick Bowler reports:
There are no unusual messages on the client... but I just logged into
the server and I see lots of messages of the following form:
nfsd: request from insecure port (192.168.8.199:35766)!
nfsd: request from insecure port (192.168.8.199:35766)!
nfsd: request from insecure port (192.168.8.199:35766)!
nfsd: request from insecure port (192.168.8.199:35766)!
nfsd: request from insecure port (192.168.8.199:35766)!
Bisected to commit 9247685088398cf21bcb513bd2832b4cd42516c4 (SUNRPC:
Properly initialize sock_xprt.srcaddr in all cases)
Apparently, removing the 'transport->srcaddr.ss_family = family' from
xs_create_sock() triggers this due to nlmclnt_lookup_host() incorrectly
initialising the srcaddr family to AF_UNSPEC.
Reported-by: Nick Bowler <nbowler@elliptictech.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes:
GFS2: Fix inode deallocation race
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This area of the code has always been a bit delicate due to the
subtleties of lock ordering. The problem is that for "normal"
alloc/dealloc, we always grab the inode locks first and the rgrp lock
later.
In order to ensure no races in looking up the unlinked, but still
allocated inodes, we need to hold the rgrp lock when we do the lookup,
which means that we can't take the inode glock.
The solution is to borrow the technique already used by NFS to solve
what is essentially the same problem (given an inode number, look up
the inode carefully, checking that it really is in the expected
state).
We cannot do that directly from the allocation code (lock ordering
again) so we give the job to the pre-existing delete workqueue and
carry on with the allocation as normal.
If we find there is no space, we do a journal flush (required anyway
if space from a deallocation is to be released) which should block
against the pending deallocations, so we should always get the space
back.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
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