p_count is the only writeable memeber of struct rpc_procinfo, which is
a good candidate to be const-ified as it contains function pointers.

This patch moves it into out out struct rpc_procinfo, and into a
separate writable array that is pointed to by struct rpc_version and
indexed by p_statidx.
Signed-off-by: NChristoph Hellwig <hch@lst.de>

Instead declare all functions with the proper methods signature.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Acked-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Declare the p_decode callbacks with the proper prototype instead of
casting to kxdrdproc_t and losing all type safety.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Acked-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Declare the p_encode callbacks with the proper prototype instead of
casting to kxdreproc_t and losing all type safety.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Acked-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Layoutstats is always desirable when using the flexfiles driver, so
we should enable it if that driver is being loaded. It is safe to do
so, because even when the mount specifies NFSv4.1, we will turn it
off if the server tells us it is unsupported.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

It turns out the Linux server has a bug in its implementation of
supattr_exclcreat; it returns the set of all attributes, whether
or not they are supported by minor version 1.
In order to avoid a regression, we therefore apply the supported_attrs
as a mask on top of whatever the server sent us.
Reported-by: NAnna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Instead of messing with the commit path which has been causing issues,
add a COMMIT op after the COPY and ask for stable copies in the first
space.

It saves a round trip, since after the COPY, the client sends a COMMIT
anyway.
Signed-off-by: NOlga Kornievskaia <kolga@netapp.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

When using NFS4_CREATE_EXCLUSIVE4_1 mode, the client will overestimate the
amount of space that it needs for the attributes because it does so
before checking whether or not the server supports a given attribute.

Fix by checking the attribute mask earlier.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

The intention in the original patch was to release the lock when
we put the inode, however something got screwed up.
Reported-by: NJason Yan <yanaijie@huawei.com>
Fixes: 7b410d9c ("pNFS: Delay getting the layout header in..")
Cc: stable@vger.kernel.org # v4.10+
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

This patch removes useless nfs_readdir_get_array() and
nfs_readdir_release_array() as suggested by Trond Myklebust

nfs_readdir() calls nfs_revalidate_mapping() before
readdir_search_pagecache() , nfs_do_filldir(), uncached_readdir()
so mapping should be correct.

While kmap() can't fail, all subsequent error checks were removed
as well as unused labels.
Signed-off-by: NFabian Frederick <fabf@skynet.be>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

When using 'ls -l' to display a large directory, if noac option is used,
in function nfs_getattr() nfs_need_revalidate_inode() will always be true
for NFSv3 and the nfs_entry cache of the directory will be flushed. The
flush will lead to a fully reread of the directory entries from server.

To prevent the unnecessary RPCs, we need to check whether or not the
noac option is used, and always report the invocation of nfs_getattr()
as cache hit instead cache miss when it's on.
Signed-off-by: NHou Tao <houtao1@huawei.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If memory allocation fails for the callback data, we need to put the nfs_client
or we end up with an elevated refcount.
Signed-off-by: NDave Wysochanski <dwysocha@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If the server returns NFS4ERR_CONN_NOT_BOUND_TO_SESSION because we
are trunking, then RECLAIM_COMPLETE must handle that by calling
nfs4_schedule_session_recovery() and then retrying.
Reported-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>
Tested-by: NChuck Lever <chuck.lever@oracle.com>

In commit 0d3b12584972 "nfs: Convert to separately allocated bdi" I have
wrongly cloned bdi reference in nfs_clone_super(). Further inspection
has shown that originally the code was actually allocating a new bdi (in
->clone_server callback) which was later registered in
nfs_fs_mount_common() and used for sb->s_bdi in nfs_initialise_sb().
This could later result in bdi for the original superblock not getting
unregistered when that superblock got shutdown (as the cloned sb still
held bdi reference) and later when a new superblock was created under
the same anonymous device number, a clash in sysfs has happened on bdi
registration:

------------[ cut here ]------------
WARNING: CPU: 1 PID: 10284 at /linux-next/fs/sysfs/dir.c:31 sysfs_warn_dup+0x64/0x74
sysfs: cannot create duplicate filename '/devices/virtual/bdi/0:32'
Modules linked in: axp20x_usb_power gpio_axp209 nvmem_sunxi_sid sun4i_dma sun4i_ss virt_dma
CPU: 1 PID: 10284 Comm: mount.nfs Not tainted 4.11.0-rc4+ #14
Hardware name: Allwinner sun7i (A20) Family
[<c010f19c>] (unwind_backtrace) from [<c010bc74>] (show_stack+0x10/0x14)
[<c010bc74>] (show_stack) from [<c03c6e24>] (dump_stack+0x78/0x8c)
[<c03c6e24>] (dump_stack) from [<c0122200>] (__warn+0xe8/0x100)
[<c0122200>] (__warn) from [<c0122250>] (warn_slowpath_fmt+0x38/0x48)
[<c0122250>] (warn_slowpath_fmt) from [<c02ac178>] (sysfs_warn_dup+0x64/0x74)
[<c02ac178>] (sysfs_warn_dup) from [<c02ac254>] (sysfs_create_dir_ns+0x84/0x94)
[<c02ac254>] (sysfs_create_dir_ns) from [<c03c8b8c>] (kobject_add_internal+0x9c/0x2ec)
[<c03c8b8c>] (kobject_add_internal) from [<c03c8e24>] (kobject_add+0x48/0x98)
[<c03c8e24>] (kobject_add) from [<c048d75c>] (device_add+0xe4/0x5a0)
[<c048d75c>] (device_add) from [<c048ddb4>] (device_create_groups_vargs+0xac/0xbc)
[<c048ddb4>] (device_create_groups_vargs) from [<c048dde4>] (device_create_vargs+0x20/0x28)
[<c048dde4>] (device_create_vargs) from [<c02075c8>] (bdi_register_va+0x44/0xfc)
[<c02075c8>] (bdi_register_va) from [<c023d378>] (super_setup_bdi_name+0x48/0xa4)
[<c023d378>] (super_setup_bdi_name) from [<c0312ef4>] (nfs_fill_super+0x1a4/0x204)
[<c0312ef4>] (nfs_fill_super) from [<c03133f0>] (nfs_fs_mount_common+0x140/0x1e8)
[<c03133f0>] (nfs_fs_mount_common) from [<c03335cc>] (nfs4_remote_mount+0x50/0x58)
[<c03335cc>] (nfs4_remote_mount) from [<c023ef98>] (mount_fs+0x14/0xa4)
[<c023ef98>] (mount_fs) from [<c025cba0>] (vfs_kern_mount+0x54/0x128)
[<c025cba0>] (vfs_kern_mount) from [<c033352c>] (nfs_do_root_mount+0x80/0xa0)
[<c033352c>] (nfs_do_root_mount) from [<c0333818>] (nfs4_try_mount+0x28/0x3c)
[<c0333818>] (nfs4_try_mount) from [<c0313874>] (nfs_fs_mount+0x2cc/0x8c4)
[<c0313874>] (nfs_fs_mount) from [<c023ef98>] (mount_fs+0x14/0xa4)
[<c023ef98>] (mount_fs) from [<c025cba0>] (vfs_kern_mount+0x54/0x128)
[<c025cba0>] (vfs_kern_mount) from [<c02600f0>] (do_mount+0x158/0xc7c)
[<c02600f0>] (do_mount) from [<c0260f98>] (SyS_mount+0x8c/0xb4)
[<c0260f98>] (SyS_mount) from [<c0107840>] (ret_fast_syscall+0x0/0x3c)

Fix the problem by always creating new bdi for a superblock as we used
to do.
Reported-and-tested-by: NCorentin Labbe <clabbe.montjoie@gmail.com>
Fixes: 0d3b12584972ce5781179ad3f15cca3cdb5cae05
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJens Axboe <axboe@fb.com>

Signed-off-by: NFred Isaman <fred.isaman@gmail.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If the layout segment is invalid, we want to just resend the remaining
writes.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Consider the following deadlock:

Process P1	Process P2		Process P3
==========	==========		==========
					lock_page(page)

		lseg = pnfs_update_layout(inode)

lo = NFS_I(inode)->layout
pnfs_error_mark_layout_for_return(lo)

		lock_page(page)

					lseg = pnfs_update_layout(inode)

In this scenario,
- P1 has declared the layout to be in error, but P2 holds a reference to
  a layout segment on that inode, so the layoutreturn is deferred.
- P2 is waiting for a page lock held by P3.
- P3 is asking for a new layout segment, but is blocked waiting
  for the layoutreturn.

The fix is to ensure that pnfs_error_mark_layout_for_return() does
not set the NFS_LAYOUT_RETURN flag, which blocks P3. Instead, we allow
the latter to call LAYOUTGET so that it can make progress and unblock
P2.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

In pnfs_clear_layoutreturn_info, ensure that we don't clear the layout
return info if there are new segments queued for return due to, for
instance, a race between a LAYOUTRETURN and a failed I/O attempt.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If the layout is being invalidated on the server, then we must
invoke nfs_commit_inode() to ensure any commits to the DS get
cleared out.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If the layout was invalidated, then assume we should requeue all the
pending writes for the DS in question.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If the attempt to write through pNFS fails, we need to use the same
failure semantics as for the read path: If the FF_FLAGS_NO_IO_THRU_MDS
flag is set or we have sufficient valid DSes, then we must retry through
pNFS

Fixes: d67ae825 ("pnfs/flexfiles: Add the FlexFile Layout Driver")
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

pnfs_error_mark_layout_for_return needs to check that the layout is
valid before calling pnfs_set_plh_return_info().
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If the RPC slot was interrupted and server replied to the next
operation on the "reused" slot with ERR_DELAY, don't clear out
the "interrupted" flag until we properly recover.
Signed-off-by: NOlga Kornievskaia <kolga@netapp.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Function xdr_inline_decode() will return a NULL pointer if the input
buffer does not have long enough buffer to decode nbytes of data.
However, in function decode_op_map(), the return value of
xdr_inline_decode() is not validated before it is used. This patch adds
a check to the return value of xdr_inline_decode().
Signed-off-by: NPan Bian <bianpan2016@163.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Calling pnfs_put_lset on an IS_ERR pointer results in a NULL pointer
dereference like the one below. At the same time the check of retvalue
of filelayout_check_deviceid() sets lseg to error, but does not free it
before that.

[ 3000.636161] BUG: unable to handle kernel NULL pointer dereference at 000000000000003c
[ 3000.636970] IP: pnfs_put_lseg+0x29/0x100 [nfsv4]
[ 3000.637420] PGD 4f23b067
[ 3000.637421] PUD 4a0f4067
[ 3000.637679] PMD 0
[ 3000.637937]
[ 3000.638287] Oops: 0000 [#1] SMP
[ 3000.638591] Modules linked in: nfs_layout_nfsv41_files nfsv3 nfnetlink_queue nfnetlink_log nfnetlink bluetooth rfkill rpcsec_gss_krb5 nfsv4 nfs fscache binfmt_misc arc4 md4 nls_utf8 cifs ccm dns_resolver rpcrdma ib_isert iscsi_target_mod ib_iser rdma_cm iw_cm libiscsi scsi_transport_iscsi ib_srpt target_core_mod ib_srp scsi_transport_srp ib_ipoib ib_ucm ib_uverbs ib_umad ib_cm ib_core nls_koi8_u nls_cp932 ts_kmp nf_conntrack_ipv4 nf_defrag_ipv4 nf_conntrack crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcspkr virtio_balloon ppdev virtio_rng parport_pc i2c_piix4 parport acpi_cpufreq nfsd auth_rpcgss nfs_acl lockd grace sunrpc xfs libcrc32c ata_generic pata_acpi virtio_blk virtio_net cirrus drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops crc32c_intel ata_piix ttm libata drm serio_raw
[ 3000.645245]  i2c_core virtio_pci virtio_ring virtio floppy dm_mirror dm_region_hash dm_log dm_mod [last unloaded: xt_u32]
[ 3000.646360] CPU: 1 PID: 26402 Comm: date Not tainted 4.11.0-rc7.1.el7.test.x86_64 #1
[ 3000.647092] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
[ 3000.647638] task: ffff8800415ada00 task.stack: ffffc90000ff0000
[ 3000.648207] RIP: 0010:pnfs_put_lseg+0x29/0x100 [nfsv4]
[ 3000.648696] RSP: 0018:ffffc90000ff39b8 EFLAGS: 00010246
[ 3000.649193] RAX: 0000000000000000 RBX: fffffffffffffff4 RCX: 00000000000d43be
[ 3000.649859] RDX: 00000000000d43bd RSI: 0000000000000000 RDI: fffffffffffffff4
[ 3000.650530] RBP: ffffc90000ff39d8 R08: 000000000001e320 R09: ffffffffa05c35ce
[ 3000.651203] R10: ffff88007fd1e320 R11: ffffea0001283d80 R12: 0000000001400040
[ 3000.651875] R13: ffff88004f77d9f0 R14: ffffc90000ff3cd8 R15: ffff8800417ade00
[ 3000.652546] FS:  00007fac4d5cd740(0000) GS:ffff88007fd00000(0000) knlGS:0000000000000000
[ 3000.653304] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 3000.653849] CR2: 000000000000003c CR3: 000000004f080000 CR4: 00000000000406e0
[ 3000.654527] Call Trace:
[ 3000.654771]  fl_pnfs_update_layout.constprop.20+0x10c/0x150 [nfs_layout_nfsv41_files]
[ 3000.655505]  filelayout_pg_init_write+0x21d/0x270 [nfs_layout_nfsv41_files]
[ 3000.656195]  __nfs_pageio_add_request+0x11c/0x490 [nfs]
[ 3000.656698]  nfs_pageio_add_request+0xac/0x260 [nfs]
[ 3000.657180]  nfs_do_writepage+0x109/0x2e0 [nfs]
[ 3000.657616]  nfs_writepages_callback+0x16/0x30 [nfs]
[ 3000.658096]  write_cache_pages+0x26f/0x510
[ 3000.658495]  ? nfs_do_writepage+0x2e0/0x2e0 [nfs]
[ 3000.658946]  ? _raw_spin_unlock_bh+0x1e/0x20
[ 3000.659357]  ? wb_wakeup_delayed+0x5f/0x70
[ 3000.659748]  ? __mark_inode_dirty+0x2eb/0x360
[ 3000.660170]  nfs_writepages+0x84/0xd0 [nfs]
[ 3000.660575]  ? nfs_updatepage+0x571/0xb70 [nfs]
[ 3000.661012]  do_writepages+0x1e/0x30
[ 3000.661358]  __filemap_fdatawrite_range+0xc6/0x100
[ 3000.661819]  filemap_write_and_wait_range+0x41/0x90
[ 3000.662292]  nfs_file_fsync+0x34/0x1f0 [nfs]
[ 3000.662704]  vfs_fsync_range+0x3d/0xb0
[ 3000.663065]  vfs_fsync+0x1c/0x20
[ 3000.663385]  nfs4_file_flush+0x57/0x80 [nfsv4]
[ 3000.663813]  filp_close+0x2f/0x70
[ 3000.664132]  __close_fd+0x9a/0xc0
[ 3000.664453]  SyS_close+0x23/0x50
[ 3000.664785]  do_syscall_64+0x67/0x180
[ 3000.665162]  entry_SYSCALL64_slow_path+0x25/0x25
[ 3000.665600] RIP: 0033:0x7fac4d0e1e90
[ 3000.665946] RSP: 002b:00007ffd54e90c88 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
[ 3000.666679] RAX: ffffffffffffffda RBX: 00007fac4d3b5400 RCX: 00007fac4d0e1e90
[ 3000.667349] RDX: 0000000000000000 RSI: 00007fac4d5d9000 RDI: 0000000000000001
[ 3000.668031] RBP: 0000000000000000 R08: 00007fac4d3b6a00 R09: 00007fac4d5cd740
[ 3000.668709] R10: 00007ffd54e909e0 R11: 0000000000000246 R12: 0000000000000000
[ 3000.669385] R13: 00007fac4d3b5e80 R14: 0000000000000000 R15: 0000000000000000
[ 3000.670061] Code: 00 00 66 66 66 66 90 55 48 85 ff 48 89 e5 41 56 41 55 41 54 53 48 89 fb 0f 84 97 00 00 00 f6 05 16 8f bc ff 10 0f 85 a6 00 00 00 <4c> 8b 63 48 48 8d 7b 38 49 8b 84 24 90 00 00 00 4c 8d a8 88 00
[ 3000.671831] RIP: pnfs_put_lseg+0x29/0x100 [nfsv4] RSP: ffffc90000ff39b8
[ 3000.672462] CR2: 000000000000003c
Signed-off-by: NArtem Savkov <asavkov@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

We want to use kthread_stop() in order to ensure the threads are
shut down before we tear down the nfs_callback_info in nfs_callback_down.
Tested-and-reviewed-by: NKinglong Mee <kinglongmee@gmail.com>
Reported-by: NKinglong Mee <kinglongmee@gmail.com>
Fixes: bb6aeba7 ("NFSv4.x: Switch to using svc_set_num_threads()...")
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

As the comments for svc_set_num_threads() said,
" Destroying threads relies on the service threads filling in
rqstp->rq_task, which only the nfs ones do.  Assumes the serv
has been created using svc_create_pooled()."

If creating service through svc_create(), the svc_pool_map_put()
will be called in svc_destroy(), but the pool map isn't used.
So that, the reference of pool map will be drop, the next using
of pool map will get a zero npools.

[  137.992130] divide error: 0000 [#1] SMP
[  137.992148] Modules linked in: nfsd(E) nfsv4 nfs fscache fuse tun bridge stp llc ip_set nfnetlink vmw_vsock_vmci_transport vsock snd_seq_midi snd_seq_midi_event vmw_balloon coretemp crct10dif_pclmul crc32_pclmul ppdev ghash_clmulni_intel intel_rapl_perf joydev snd_ens1371 gameport snd_ac97_codec ac97_bus snd_seq snd_pcm snd_rawmidi snd_timer snd_seq_device snd soundcore parport_pc parport nfit acpi_cpufreq tpm_tis tpm_tis_core tpm vmw_vmci i2c_piix4 shpchp auth_rpcgss nfs_acl lockd(E) grace sunrpc(E) xfs libcrc32c vmwgfx drm_kms_helper ttm crc32c_intel drm e1000 mptspi scsi_transport_spi serio_raw mptscsih mptbase ata_generic pata_acpi [last unloaded: nfsd]
[  137.992336] CPU: 0 PID: 4514 Comm: rpc.nfsd Tainted: G            E   4.11.0-rc8+ #536
[  137.992777] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/02/2015
[  137.993757] task: ffff955984101d00 task.stack: ffff9873c2604000
[  137.994231] RIP: 0010:svc_pool_for_cpu+0x2b/0x80 [sunrpc]
[  137.994768] RSP: 0018:ffff9873c2607c18 EFLAGS: 00010246
[  137.995227] RAX: 0000000000000000 RBX: ffff95598376f000 RCX: 0000000000000002
[  137.995673] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff9559944aec00
[  137.996156] RBP: ffff9873c2607c18 R08: ffff9559944aec28 R09: 0000000000000000
[  137.996609] R10: 0000000001080002 R11: 0000000000000000 R12: ffff95598376f010
[  137.997063] R13: ffff95598376f018 R14: ffff9559944aec28 R15: ffff9559944aec00
[  137.997584] FS:  00007f755529eb40(0000) GS:ffff9559bb600000(0000) knlGS:0000000000000000
[  137.998048] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  137.998548] CR2: 000055f3aecd9660 CR3: 0000000084290000 CR4: 00000000001406f0
[  137.999052] Call Trace:
[  137.999517]  svc_xprt_do_enqueue+0xef/0x260 [sunrpc]
[  138.000028]  svc_xprt_received+0x47/0x90 [sunrpc]
[  138.000487]  svc_add_new_perm_xprt+0x76/0x90 [sunrpc]
[  138.000981]  svc_addsock+0x14b/0x200 [sunrpc]
[  138.001424]  ? recalc_sigpending+0x1b/0x50
[  138.001860]  ? __getnstimeofday64+0x41/0xd0
[  138.002346]  ? do_gettimeofday+0x29/0x90
[  138.002779]  write_ports+0x255/0x2c0 [nfsd]
[  138.003202]  ? _copy_from_user+0x4e/0x80
[  138.003676]  ? write_recoverydir+0x100/0x100 [nfsd]
[  138.004098]  nfsctl_transaction_write+0x48/0x80 [nfsd]
[  138.004544]  __vfs_write+0x37/0x160
[  138.004982]  ? selinux_file_permission+0xd7/0x110
[  138.005401]  ? security_file_permission+0x3b/0xc0
[  138.005865]  vfs_write+0xb5/0x1a0
[  138.006267]  SyS_write+0x55/0xc0
[  138.006654]  entry_SYSCALL_64_fastpath+0x1a/0xa9
[  138.007071] RIP: 0033:0x7f7554b9dc30
[  138.007437] RSP: 002b:00007ffc9f92c788 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[  138.007807] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f7554b9dc30
[  138.008168] RDX: 0000000000000002 RSI: 00005640cd536640 RDI: 0000000000000003
[  138.008573] RBP: 00007ffc9f92c780 R08: 0000000000000001 R09: 0000000000000002
[  138.008918] R10: 0000000000000064 R11: 0000000000000246 R12: 0000000000000004
[  138.009254] R13: 00005640cdbf77a0 R14: 00005640cdbf7720 R15: 00007ffc9f92c238
[  138.009610] Code: 0f 1f 44 00 00 48 8b 87 98 00 00 00 55 48 89 e5 48 83 78 08 00 74 10 8b 05 07 42 02 00 83 f8 01 74 40 83 f8 02 74 19 31 c0 31 d2 <f7> b7 88 00 00 00 5d 89 d0 48 c1 e0 07 48 03 87 90 00 00 00 c3
[  138.010664] RIP: svc_pool_for_cpu+0x2b/0x80 [sunrpc] RSP: ffff9873c2607c18
[  138.011061] ---[ end trace b3468224cafa7d11 ]---
Signed-off-by: NKinglong Mee <kinglongmee@gmail.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

If the client receives a fatal server error from nfs_pageio_add_request(),
then we should always truncate the page on which the error occurred.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

EACCES, EDQUOT, EFBIG and ESTALE are all fatal errors as far as NFS
I/O is concerned. They need to be reported back to the application.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

Fix compiler warnings.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If the server has already returned a fatal write error that the user
has not yet received on this file, then don't write back the other pages.
Instead, act as if they have been sent, and have returned with the same
error.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

The assumption should be that if the caller returns PNFS_ATTEMPTED, then hdr
has been consumed, and so we should not be testing hdr->task.tk_status.
If the caller returns PNFS_TRY_AGAIN, then we need to recoalesce and
free hdr.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

If we have a layout segment cached in pgio->pg_lseg, we should check it
for validity before reusing it in a new RPC request. Otherwise, if we
recoalesce, we can end up looping forever.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

NFS attempts to wait for read and write completion before unlocking in
order to ensure that the data returned was protected by the lock.  When
this waiting is interrupted by a signal, the unlock may be skipped, and
messages similar to the following are seen in the kernel ring buffer:

[20.167876] Leaked locks on dev=0x0:0x2b ino=0x8dd4c3:
[20.168286] POSIX: fl_owner=ffff880078b06940 fl_flags=0x1 fl_type=0x0 fl_pid=20183
[20.168727] POSIX: fl_owner=ffff880078b06680 fl_flags=0x1 fl_type=0x0 fl_pid=20185

For NFSv3, the missing unlock will cause the server to refuse conflicting
locks indefinitely.  For NFSv4, the leftover lock will be removed by the
server after the lease timeout.

This patch fixes this issue by skipping the usual wait in
nfs_iocounter_wait if the FL_CLOSE flag is set when signaled.  Instead, the
wait happens in the unlock RPC task on the NFS UOC rpc_waitqueue.

For NFSv3, use lockd's new nlmclnt_operations along with
nfs_async_iocounter_wait to defer NLM's unlock task until the lock
context's iocounter reaches zero.

For NFSv4, call nfs_async_iocounter_wait() directly from unlock's
current rpc_call_prepare.
Signed-off-by: NBenjamin Coddington <bcodding@redhat.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

NFS would enjoy the ability to modify the behavior of the NLM client's
unlock RPC task in order to delay the transmission of the unlock until IO
that was submitted under that lock has completed.  This ability can ensure
that the NLM client will always complete the transmission of an unlock even
if the waiting caller has been interrupted with fatal signal.

For this purpose, a pointer to a struct nlmclnt_operations can be assigned
in a nfs_module's nfs_rpc_ops that will install those nlmclnt_operations on
the nlm_host.  The struct nlmclnt_operations defines three callback
operations that will be used in a following patch:

nlmclnt_alloc_call - used to call back after a successful allocation of
	a struct nlm_rqst in nlmclnt_proc().

nlmclnt_unlock_prepare - used to call back during NLM unlock's
	rpc_call_prepare.  The NLM client defers calling rpc_call_start()
	until this callback returns false.

nlmclnt_release_call - used to call back when the NLM client's struct
	nlm_rqst is freed.
Signed-off-by: NBenjamin Coddington <bcodding@redhat.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

By sleeping on a new NFS Unlock-On-Close waitqueue, rpc tasks may wait for
a lock context's iocounter to reach zero.  The rpc waitqueue is only woken
when the open_context has the NFS_CONTEXT_UNLOCK flag set in order to
mitigate spurious wake-ups for any iocounter reaching zero.
Signed-off-by: NBenjamin Coddington <bcodding@redhat.com>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

We only need to check lock exclusive/shared types against open mode when
flock() is used on NFS, so move it into the flock-specific path instead of
checking it for all locks.
Signed-off-by: NBenjamin Coddington <bcodding@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

flock64_to_posix_lock() is already doing this check
Signed-off-by: NBenjamin Coddington <bcodding@redhat.com>
Reviewed-by: NJeff Layton <jeff.layton@primarydata.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

It is not used outside the NFSv4 module.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>

They are not used outside the NFSv4 module.
Signed-off-by: NTrond Myklebust <trond.myklebust@primarydata.com>