Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Backchannel xprt isn't freed right now.
Free it in bc_destroy, and put the reference of THIS_MODULE.
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Testing NFS4.0 by pynfs, I got some messeages as,
"nfsd: inode locked twice during operation."

When one compound RPC contains two or more ops that locks
the filehandle,the second op will cause the message.

As two SETATTR ops, after the first SETATTR, nfsd will not call
fh_put() to release current filehandle, it means filehandle have
unlocked with fh_post_saved = 1.
The second SETATTR find fh_post_saved = 1, and printk the message.

v2: introduce helper fh_clear_wcc().
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

RFC5661 obsoletes NFS4ERR_STALE_STATEID in favour of NFS4ERR_BAD_STATEID.

Note that because nfsd encodes the clientid boot time in the stateid, we
can hit this error case in certain scenarios where the Linux client
state management thread exits early, before it has finished recovering
all state.
Reported-by: NIdan Kedar <idank@primarydata.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

encode_getattr, for example, can return nfserr_resource to indicate it
ran out of buffer space.  That's not a legal error in the 4.1 case.  And
in the 4.1 case, if we ran out of buffer space, we should have exceeded
a session limit too.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Cc: stable@vger.kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

cstate->slot and ->session are each set together in nfsd4_sequence.  If
one is non-NULL, so is the other.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Maybe this is comment true, who cares?  Handle this like any other
error.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

This isn't actually used anywhere else.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Allow

	xdr_buf_subsegment(&buf, &buf, base, len)

to modify an xdr_buf in-place.

Also, none of the callers need the iov_base of head or tail to be zeroed
out.

Also add documentation.

(As it turns out, I'm not really using this new guarantee, but it seems
a simple way to make this function a bit more robust.)
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Connection from alloc_conn must be freed through free_conn,
otherwise, the reference of svc_xprt will never be put.
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Creating xprt failed after xs_format_peer_addresses,
sunrpc must free those memory of peer addresses in xprt.
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The xdr_off value in dma_map_xdr gets passed to ib_dma_map_page as the
offset into the page to be mapped. This calculation does not correctly
take into account the case where the data starts at some offset into
the page. Increment the xdr_off by the page_base to ensure that it is
respected.

Cc: Tom Tucker <tom@opengridcomputing.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

There are two entirely separate modules under xprtrdma/ and there's no
reason that enabling one should automatically enable the other. Add
config options for each one so they can be enabled/disabled separately.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The server regression was caused by the addition of rq_next_page
(afc59400). There were a few places that
were missed with the update of the rq_respages array.
Signed-off-by: NTom Tucker <tom@ogc.us>
Tested-by: NSteve Wise <swise@ogc.us>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

We had a Fedora ABRT report with a stack trace like this:

kernel BUG at net/sunrpc/svc.c:550!
invalid opcode: 0000 [#1] SMP
[...]
CPU: 2 PID: 913 Comm: rpc.nfsd Not tainted 3.13.6-200.fc20.x86_64 #1
Hardware name: Hewlett-Packard HP ProBook 4740s/1846, BIOS 68IRR Ver. F.40 01/29/2013
task: ffff880146b00000 ti: ffff88003f9b8000 task.ti: ffff88003f9b8000
RIP: 0010:[<ffffffffa0305fa8>]  [<ffffffffa0305fa8>] svc_destroy+0x128/0x130 [sunrpc]
RSP: 0018:ffff88003f9b9de0  EFLAGS: 00010206
RAX: ffff88003f829628 RBX: ffff88003f829600 RCX: 00000000000041ee
RDX: 0000000000000000 RSI: 0000000000000286 RDI: 0000000000000286
RBP: ffff88003f9b9de8 R08: 0000000000017360 R09: ffff88014fa97360
R10: ffffffff8114ce57 R11: ffffea00051c9c00 R12: ffff88003f829600
R13: 00000000ffffff9e R14: ffffffff81cc7cc0 R15: 0000000000000000
FS:  00007f4fde284840(0000) GS:ffff88014fa80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4fdf5192f8 CR3: 00000000a569a000 CR4: 00000000001407e0
Stack:
 ffff88003f792300 ffff88003f9b9e18 ffffffffa02de02a 0000000000000000
 ffffffff81cc7cc0 ffff88003f9cb000 0000000000000008 ffff88003f9b9e60
 ffffffffa033bb35 ffffffff8131c86c ffff88003f9cb000 ffff8800a5715008
Call Trace:
 [<ffffffffa02de02a>] lockd_up+0xaa/0x330 [lockd]
 [<ffffffffa033bb35>] nfsd_svc+0x1b5/0x2f0 [nfsd]
 [<ffffffff8131c86c>] ? simple_strtoull+0x2c/0x50
 [<ffffffffa033c630>] ? write_pool_threads+0x280/0x280 [nfsd]
 [<ffffffffa033c6bb>] write_threads+0x8b/0xf0 [nfsd]
 [<ffffffff8114efa4>] ? __get_free_pages+0x14/0x50
 [<ffffffff8114eff6>] ? get_zeroed_page+0x16/0x20
 [<ffffffff811dec51>] ? simple_transaction_get+0xb1/0xd0
 [<ffffffffa033c098>] nfsctl_transaction_write+0x48/0x80 [nfsd]
 [<ffffffff811b8b34>] vfs_write+0xb4/0x1f0
 [<ffffffff811c3f99>] ? putname+0x29/0x40
 [<ffffffff811b9569>] SyS_write+0x49/0xa0
 [<ffffffff810fc2a6>] ? __audit_syscall_exit+0x1f6/0x2a0
 [<ffffffff816962e9>] system_call_fastpath+0x16/0x1b
Code: 31 c0 e8 82 db 37 e1 e9 2a ff ff ff 48 8b 07 8b 57 14 48 c7 c7 d5 c6 31 a0 48 8b 70 20 31 c0 e8 65 db 37 e1 e9 f4 fe ff ff 0f 0b <0f> 0b 66 0f 1f 44 00 00 0f 1f 44 00 00 55 48 89 e5 41 56 41 55
RIP  [<ffffffffa0305fa8>] svc_destroy+0x128/0x130 [sunrpc]
 RSP <ffff88003f9b9de0>

Evidently, we created some lockd sockets and then failed to create
others. make_socks then returned an error and we tried to tear down the
svc, but svc->sv_permsocks was not empty so we ended up tripping over
the BUG() in svc_destroy().

Fix this by ensuring that we tear down any live sockets we created when
socket creation is going to return an error.

Fixes: 786185b5 (SUNRPC: move per-net operations from...)
Reported-by: NRaphos <raphoszap@laposte.net>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Reviewed-by: NStanislav Kinsbursky <skinsbursky@parallels.com>
Cc: stable@vger.kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

When stopping nfsd, I got BUG messages, and soft lockup messages,
The problem is cuased by double rb_erase() in nfs4_state_destroy_net()
and destroy_client().

This patch just let nfsd traversing unconfirmed client through
hash-table instead of rbtree.

[ 2325.021995] BUG: unable to handle kernel NULL pointer dereference at
          (null)
[ 2325.022809] IP: [<ffffffff8133c18c>] rb_erase+0x14c/0x390
[ 2325.022982] PGD 7a91b067 PUD 7a33d067 PMD 0
[ 2325.022982] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC
[ 2325.022982] Modules linked in: nfsd(OF) cfg80211 rfkill bridge stp
llc snd_intel8x0 snd_ac97_codec ac97_bus auth_rpcgss nfs_acl serio_raw
e1000 i2c_piix4 ppdev snd_pcm snd_timer lockd pcspkr joydev parport_pc
snd parport i2c_core soundcore microcode sunrpc ata_generic pata_acpi
[last unloaded: nfsd]
[ 2325.022982] CPU: 1 PID: 2123 Comm: nfsd Tainted: GF          O
3.14.0-rc8+ #2
[ 2325.022982] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS
VirtualBox 12/01/2006
[ 2325.022982] task: ffff88007b384800 ti: ffff8800797f6000 task.ti:
ffff8800797f6000
[ 2325.022982] RIP: 0010:[<ffffffff8133c18c>]  [<ffffffff8133c18c>]
rb_erase+0x14c/0x390
[ 2325.022982] RSP: 0018:ffff8800797f7d98  EFLAGS: 00010246
[ 2325.022982] RAX: ffff880079c1f010 RBX: ffff880079f4c828 RCX:
0000000000000000
[ 2325.022982] RDX: 0000000000000000 RSI: ffff880079bcb070 RDI:
ffff880079f4c810
[ 2325.022982] RBP: ffff8800797f7d98 R08: 0000000000000000 R09:
ffff88007964fc70
[ 2325.022982] R10: 0000000000000000 R11: 0000000000000400 R12:
ffff880079f4c800
[ 2325.022982] R13: ffff880079bcb000 R14: ffff8800797f7da8 R15:
ffff880079f4c860
[ 2325.022982] FS:  0000000000000000(0000) GS:ffff88007f900000(0000)
knlGS:0000000000000000
[ 2325.022982] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 2325.022982] CR2: 0000000000000000 CR3: 000000007a3ef000 CR4:
00000000000006e0
[ 2325.022982] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[ 2325.022982] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
0000000000000400
[ 2325.022982] Stack:
[ 2325.022982]  ffff8800797f7de0 ffffffffa0191c6e ffff8800797f7da8
ffff8800797f7da8
[ 2325.022982]  ffff880079f4c810 ffff880079bcb000 ffffffff81cc26c0
ffff880079c1f010
[ 2325.022982]  ffff880079bcb070 ffff8800797f7e28 ffffffffa01977f2
ffff8800797f7df0
[ 2325.022982] Call Trace:
[ 2325.022982]  [<ffffffffa0191c6e>] destroy_client+0x32e/0x3b0 [nfsd]
[ 2325.022982]  [<ffffffffa01977f2>] nfs4_state_shutdown_net+0x1a2/0x220
[nfsd]
[ 2325.022982]  [<ffffffffa01700b8>] nfsd_shutdown_net+0x38/0x70 [nfsd]
[ 2325.022982]  [<ffffffffa017013e>] nfsd_last_thread+0x4e/0x80 [nfsd]
[ 2325.022982]  [<ffffffffa001f1eb>] svc_shutdown_net+0x2b/0x30 [sunrpc]
[ 2325.022982]  [<ffffffffa017064b>] nfsd_destroy+0x5b/0x80 [nfsd]
[ 2325.022982]  [<ffffffffa0170773>] nfsd+0x103/0x130 [nfsd]
[ 2325.022982]  [<ffffffffa0170670>] ? nfsd_destroy+0x80/0x80 [nfsd]
[ 2325.022982]  [<ffffffff810a8232>] kthread+0xd2/0xf0
[ 2325.022982]  [<ffffffff810a8160>] ? insert_kthread_work+0x40/0x40
[ 2325.022982]  [<ffffffff816c493c>] ret_from_fork+0x7c/0xb0
[ 2325.022982]  [<ffffffff810a8160>] ? insert_kthread_work+0x40/0x40
[ 2325.022982] Code: 48 83 e1 fc 48 89 10 0f 84 02 01 00 00 48 3b 41 10
0f 84 08 01 00 00 48 89 51 08 48 89 fa e9 74 ff ff ff 0f 1f 40 00 48 8b
50 10 <f6> 02 01 0f 84 93 00 00 00 48 8b 7a 10 48 85 ff 74 05 f6 07 01
[ 2325.022982] RIP  [<ffffffff8133c18c>] rb_erase+0x14c/0x390
[ 2325.022982]  RSP <ffff8800797f7d98>
[ 2325.022982] CR2: 0000000000000000
[ 2325.022982] ---[ end trace 28c27ed011655e57 ]---

[  228.064071] BUG: soft lockup - CPU#0 stuck for 22s! [nfsd:558]
[  228.064428] Modules linked in: ip6t_rpfilter ip6t_REJECT cfg80211
xt_conntrack rfkill ebtable_nat ebtable_broute bridge stp llc
ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6
nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw
ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4
nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security
iptable_raw nfsd(OF) auth_rpcgss nfs_acl lockd snd_intel8x0
snd_ac97_codec ac97_bus joydev snd_pcm snd_timer e1000 sunrpc snd ppdev
parport_pc serio_raw pcspkr i2c_piix4 microcode parport soundcore
i2c_core ata_generic pata_acpi
[  228.064539] CPU: 0 PID: 558 Comm: nfsd Tainted: GF          O
3.14.0-rc8+ #2
[  228.064539] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS
VirtualBox 12/01/2006
[  228.064539] task: ffff880076adec00 ti: ffff880074616000 task.ti:
ffff880074616000
[  228.064539] RIP: 0010:[<ffffffff8133ba17>]  [<ffffffff8133ba17>]
rb_next+0x27/0x50
[  228.064539] RSP: 0018:ffff880074617de0  EFLAGS: 00000282
[  228.064539] RAX: ffff880074478010 RBX: ffff88007446f860 RCX:
0000000000000014
[  228.064539] RDX: ffff880074478010 RSI: 0000000000000000 RDI:
ffff880074478010
[  228.064539] RBP: ffff880074617de0 R08: 0000000000000000 R09:
0000000000000012
[  228.064539] R10: 0000000000000001 R11: ffffffffffffffec R12:
ffffea0001d11a00
[  228.064539] R13: ffff88007f401400 R14: ffff88007446f800 R15:
ffff880074617d50
[  228.064539] FS:  0000000000000000(0000) GS:ffff88007f800000(0000)
knlGS:0000000000000000
[  228.064539] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  228.064539] CR2: 00007fe9ac6ec000 CR3: 000000007a5d6000 CR4:
00000000000006f0
[  228.064539] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[  228.064539] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
0000000000000400
[  228.064539] Stack:
[  228.064539]  ffff880074617e28 ffffffffa01ab7db ffff880074617df0
ffff880074617df0
[  228.064539]  ffff880079273000 ffffffff81cc26c0 ffffffff81cc26c0
0000000000000000
[  228.064539]  0000000000000000 ffff880074617e48 ffffffffa01840b8
ffffffff81cc26c0
[  228.064539] Call Trace:
[  228.064539]  [<ffffffffa01ab7db>] nfs4_state_shutdown_net+0x18b/0x220
[nfsd]
[  228.064539]  [<ffffffffa01840b8>] nfsd_shutdown_net+0x38/0x70 [nfsd]
[  228.064539]  [<ffffffffa018413e>] nfsd_last_thread+0x4e/0x80 [nfsd]
[  228.064539]  [<ffffffffa00aa1eb>] svc_shutdown_net+0x2b/0x30 [sunrpc]
[  228.064539]  [<ffffffffa018464b>] nfsd_destroy+0x5b/0x80 [nfsd]
[  228.064539]  [<ffffffffa0184773>] nfsd+0x103/0x130 [nfsd]
[  228.064539]  [<ffffffffa0184670>] ? nfsd_destroy+0x80/0x80 [nfsd]
[  228.064539]  [<ffffffff810a8232>] kthread+0xd2/0xf0
[  228.064539]  [<ffffffff810a8160>] ? insert_kthread_work+0x40/0x40
[  228.064539]  [<ffffffff816c493c>] ret_from_fork+0x7c/0xb0
[  228.064539]  [<ffffffff810a8160>] ? insert_kthread_work+0x40/0x40
[  228.064539] Code: 1f 44 00 00 55 48 8b 17 48 89 e5 48 39 d7 74 3b 48
8b 47 08 48 85 c0 75 0e eb 25 66 0f 1f 84 00 00 00 00 00 48 89 d0 48 8b
50 10 <48> 85 d2 75 f4 5d c3 66 90 48 3b 78 08 75 f6 48 8b 10 48 89 c7

Fixes: ac55fdc4 (nfsd: move the confirmed and unconfirmed hlists...)
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Cc: stable@vger.kernel.org
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

We have a WARN_ON in the nfsd4_decode_write() that tells us when the
client has sent a request that is not padded out properly according to
RFC4506. A WARN_ON really isn't appropriate in this case though since
this indicates a client bug, not a server one.

Move this check out to the top-level compound decoder and have it just
explicitly return an error. Also add a dprintk() that shows the client
address and xid to help track down clients and frames that trigger it.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Mark functions as static in net/sunrpc/svc_xprt.c because they are not
used outside this file.

This eliminates the following warning in net/sunrpc/svc_xprt.c:
net/sunrpc/svc_xprt.c:574:5: warning: no previous prototype for ‘svc_alloc_arg’ [-Wmissing-prototypes]
net/sunrpc/svc_xprt.c:615:18: warning: no previous prototype for ‘svc_get_next_xprt’ [-Wmissing-prototypes]
net/sunrpc/svc_xprt.c:694:6: warning: no previous prototype for ‘svc_add_new_temp_xprt’ [-Wmissing-prototypes]
Reviewed-by: NJosh Triplett <josh@joshtriplett.org>
Signed-off-by: NRashika Kheria <rashika.kheria@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

It retries in 1s, not 1000 jiffies.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Looks like this bug has been here since these write counts were
introduced, not sure why it was just noticed now.

Thanks also to Jan Kara for pointing out the problem.

Cc: stable@vger.kernel.org
Reported-by: NMatthew Rahtz <mrahtz@rapitasystems.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

If the entire operation fails then there's nothing to encode.

Cc: stable@vger.kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

This fixes an ommission from 18032ca0
"NFSD: Server implementation of MAC Labeling", which increased the size
of the setattr error reply without increasing COMPOUND_ERR_SLACK_SPACE.

Cc: stable@vger.kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

If a client attempts to set an excessively large ACL, return
NFS4ERR_FBIG instead of NFS4ERR_RESOURCE.  I'm not sure FBIG is correct,
but I'm positive RESOURCE is wrong (it isn't even a well-defined error
any more for NFS versions since 4.1).
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Cc: stable@vger.kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

This was an omission from 8c18f205
"nfsd41: SUPPATTR_EXCLCREAT attribute".

Cc: Benny Halevy <bhalevy@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

There is a regression in
	208d0acc 2014-01-07 nfsd4: break only delegations when appropriate
which deletes an nfserrno() call in nfsd_setattr() (by accident,
probably), and NFSD becomes ignoring an error from VFS.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

If an NFS client attempts to get a lock (using NLM) and the lock is
not available, the server will remember the request and when the lock
becomes available it will send a GRANT request to the client to
provide the lock.

If the client already held an adjacent lock, the GRANT callback will
report the union of the existing and new locks, which can confuse the
client.

This happens because __posix_lock_file (called by vfs_lock_file)
updates the passed-in file_lock structure when adjacent or
over-lapping locks are found.

To avoid this problem we take a copy of the two fields that can
be changed (fl_start and fl_end) before the call and restore them
afterwards.
An alternate would be to allocate a 'struct file_lock', initialise it,
use locks_copy_lock() to take a copy, then locks_release_private()
after the vfs_lock_file() call.  But that is a lot more work.
Reported-by: NOlaf Kirch <okir@suse.com>
Signed-off-by: NNeilBrown <neilb@suse.de>
Cc: stable@vger.kernel.org
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

--
v1 had a couple of issues (large on-stack struct and didn't really work properly).
This version is much better tested.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

4ac7249e "nfsd: use get_acl and
->set_acl" forgets to set the size in the case get_acl() succeeds, so
_posix_to_nfsv4_one() can then write past the end of its allocation.
Symptoms were slab corruption warnings.

Also, some minor cleanup while we're here.  (Among other things, note
that the first few lines guarantee that pacl is non-NULL.)
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Pull SELinux fixes from James Morris.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  SELinux:  Fix kernel BUG on empty security contexts.
  selinux: add SOCK_DIAG_BY_FAMILY to the list of netlink message types

Pull vfs fixes from Al Viro:
 "A couple of fixes, both -stable fodder.  The O_SYNC bug is fairly
  old..."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fix a kmap leak in virtio_console
  fix O_SYNC|O_APPEND syncing the wrong range on write()

While we are at it, don't do kmap() under kmap_atomic(), *especially*
for a page we'd allocated with GFP_KERNEL.  It's spelled "page_address",
and had that been more than that, we'd have a real trouble - kmap_high()
can block, and doing that while holding kmap_atomic() is a Bad Idea(tm).
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

It actually goes back to 2004 ([PATCH] Concurrent O_SYNC write support)
when sync_page_range() had been introduced; generic_file_write{,v}() correctly
synced
	pos_after_write - written .. pos_after_write - 1
but generic_file_aio_write() synced
	pos_before_write .. pos_before_write + written - 1
instead.  Which is not the same thing with O_APPEND, obviously.
A couple of years later correct variant had been killed off when
everything switched to use of generic_file_aio_write().

All users of generic_file_aio_write() are affected, and the same bug
has been copied into other instances of ->aio_write().

The fix is trivial; the only subtle point is that generic_write_sync()
ought to be inlined to avoid calculations useless for the majority of
calls.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Pull btrfs fixes from Chris Mason:
 "This is a small collection of fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: fix data corruption when reading/updating compressed extents
  Btrfs: don't loop forever if we can't run because of the tree mod log
  btrfs: reserve no transaction units in btrfs_ioctl_set_features
  btrfs: commit transaction after setting label and features
  Btrfs: fix assert screwup for the pending move stuff