Commit Graph

2873 Commits

Author SHA1 Message Date
Linus Torvalds c742b63473 Highlights:
- Keep nfsd clients from unnecessarily breaking their own delegations:
   Note this requires a small kthreadd addition, discussed at:
   https://lore.kernel.org/r/1588348912-24781-1-git-send-email-bfields@redhat.com
   The result is Tejun Heo's suggestion, and he was OK with this going
   through my tree.
 - Patch nfsd/clients/ to display filenames, and to fix byte-order when
   displaying stateid's.
 - fix a module loading/unloading bug, from Neil Brown.
 - A big series from Chuck Lever with RPC/RDMA and tracing improvements,
   and lay some groundwork for RPC-over-TLS.
 
 Note Stephen Rothwell spotted two conflicts in linux-next.  Both should
 be straightforward:
 	include/trace/events/sunrpc.h
 		https://lore.kernel.org/r/20200529105917.50dfc40f@canb.auug.org.au
 	net/sunrpc/svcsock.c
 		https://lore.kernel.org/r/20200529131955.26c421db@canb.auug.org.au
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCAAzFiEEYtFWavXG9hZotryuJ5vNeUKO4b4FAl7iRYwVHGJmaWVsZHNA
 ZmllbGRzZXMub3JnAAoJECebzXlCjuG+yx8QALIfyz/ziPgjGBnNJGCW8BjWHz7+
 rGI+1SP2EUpgJ0fGJc9MpGyYTa5T3pTgsENnIRtegyZDISg2OQ5GfifpkTz4U7vg
 QbWRihs/W9EhltVYhKvtLASAuSAJ8ETbDfLXVb2ncY7iO6JNvb22xwsgKZILmzm1
 uG4qSszmBZzpMUUy51kKJYJZ3ysP+v14qOnyOXEoeEMuJYNK9FkQ9bSPZ6wTJNOn
 hvZBMbU7LzRyVIvp358mFHY+vwq5qBNkJfVrZBkURGn4OxWPbWDXzqOi0Zs1oBjA
 L+QODIbTLGkopu/rD0r1b872PDtket7p5zsD8MreeI1vJOlt3xwqdCGlicIeNATI
 b0RG7sqh+pNv0mvwLxSNTf3rO0EKW6tUySqCnQZUAXFGRH0nYM2TWze4HUr2zfWT
 EgRMwxHY/AZUStZBuCIHPJ6inWnKuxSUELMf2a9JHO1BJc/yClRgmwJGdthVwb9u
 GP6F3/maFu+9YOO6iROMsqtxDA+q5vch5IBzevNOOBDEQDKqENmogR/knl9DmAhF
 sr+FOa3O0u6S4tgXw/TU97JS/h1L2Hu6QVEwU2iVzWtlUUOFVMZQODJTB6Lts4Ka
 gKzYXWvCHN+LyETsN6q7uHFg9mtO7xO5vrrIgo72SuVCscDw/8iHkoOOFLief+GE
 O0fR0IYjW8U1Rkn2
 =YEf0
 -----END PGP SIGNATURE-----

Merge tag 'nfsd-5.8' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "Highlights:

   - Keep nfsd clients from unnecessarily breaking their own
     delegations.

     Note this requires a small kthreadd addition. The result is Tejun
     Heo's suggestion (see link), and he was OK with this going through
     my tree.

   - Patch nfsd/clients/ to display filenames, and to fix byte-order
     when displaying stateid's.

   - fix a module loading/unloading bug, from Neil Brown.

   - A big series from Chuck Lever with RPC/RDMA and tracing
     improvements, and lay some groundwork for RPC-over-TLS"

Link: https://lore.kernel.org/r/1588348912-24781-1-git-send-email-bfields@redhat.com

* tag 'nfsd-5.8' of git://linux-nfs.org/~bfields/linux: (49 commits)
  sunrpc: use kmemdup_nul() in gssp_stringify()
  nfsd: safer handling of corrupted c_type
  nfsd4: make drc_slab global, not per-net
  SUNRPC: Remove unreachable error condition in rpcb_getport_async()
  nfsd: Fix svc_xprt refcnt leak when setup callback client failed
  sunrpc: clean up properly in gss_mech_unregister()
  sunrpc: svcauth_gss_register_pseudoflavor must reject duplicate registrations.
  sunrpc: check that domain table is empty at module unload.
  NFSD: Fix improperly-formatted Doxygen comments
  NFSD: Squash an annoying compiler warning
  SUNRPC: Clean up request deferral tracepoints
  NFSD: Add tracepoints for monitoring NFSD callbacks
  NFSD: Add tracepoints to the NFSD state management code
  NFSD: Add tracepoints to NFSD's duplicate reply cache
  SUNRPC: svc_show_status() macro should have enum definitions
  SUNRPC: Restructure svc_udp_recvfrom()
  SUNRPC: Refactor svc_recvfrom()
  SUNRPC: Clean up svc_release_skb() functions
  SUNRPC: Refactor recvfrom path dealing with incomplete TCP receives
  SUNRPC: Replace dprintk() call sites in TCP receive path
  ...
2020-06-11 10:33:13 -07:00
J. Bruce Fields c25bf185e5 nfsd: safer handling of corrupted c_type
This can only happen if there's a bug somewhere, so let's make it a WARN
not a printk.  Also, I think it's safest to ignore the corruption rather
than trying to fix it by removing a cache entry.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-06-03 11:12:32 -04:00
NeilBrown a37b0715dd mm/writeback: replace PF_LESS_THROTTLE with PF_LOCAL_THROTTLE
PF_LESS_THROTTLE exists for loop-back nfsd (and a similar need in the
loop block driver and callers of prctl(PR_SET_IO_FLUSHER)), where a
daemon needs to write to one bdi (the final bdi) in order to free up
writes queued to another bdi (the client bdi).

The daemon sets PF_LESS_THROTTLE and gets a larger allowance of dirty
pages, so that it can still dirty pages after other processses have been
throttled.  The purpose of this is to avoid deadlock that happen when
the PF_LESS_THROTTLE process must write for any dirty pages to be freed,
but it is being thottled and cannot write.

This approach was designed when all threads were blocked equally,
independently on which device they were writing to, or how fast it was.
Since that time the writeback algorithm has changed substantially with
different threads getting different allowances based on non-trivial
heuristics.  This means the simple "add 25%" heuristic is no longer
reliable.

The important issue is not that the daemon needs a *larger* dirty page
allowance, but that it needs a *private* dirty page allowance, so that
dirty pages for the "client" bdi that it is helping to clear (the bdi
for an NFS filesystem or loop block device etc) do not affect the
throttling of the daemon writing to the "final" bdi.

This patch changes the heuristic so that the task is not throttled when
the bdi it is writing to has a dirty page count below below (or equal
to) the free-run threshold for that bdi.  This ensures it will always be
able to have some pages in flight, and so will not deadlock.

In a steady-state, it is expected that PF_LOCAL_THROTTLE tasks might
still be throttled by global threshold, but that is acceptable as it is
only the deadlock state that is interesting for this flag.

This approach of "only throttle when target bdi is busy" is consistent
with the other use of PF_LESS_THROTTLE in current_may_throttle(), were
it causes attention to be focussed only on the target bdi.

So this patch
 - renames PF_LESS_THROTTLE to PF_LOCAL_THROTTLE,
 - removes the 25% bonus that that flag gives, and
 - If PF_LOCAL_THROTTLE is set, don't delay at all unless the
   global and the local free-run thresholds are exceeded.

Note that previously realtime threads were treated the same as
PF_LESS_THROTTLE threads.  This patch does *not* change the behvaiour
for real-time threads, so it is now different from the behaviour of nfsd
and loop tasks.  I don't know what is wanted for realtime.

[akpm@linux-foundation.org: coding style fixes]
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Chuck Lever <chuck.lever@oracle.com>	[nfsd]
Cc: Christoph Hellwig <hch@lst.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Link: http://lkml.kernel.org/r/87ftbf7gs3.fsf@notabene.neil.brown.name
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-02 10:59:08 -07:00
J. Bruce Fields 027690c75e nfsd4: make drc_slab global, not per-net
I made every global per-network-namespace instead.  But perhaps doing
that to this slab was a step too far.

The kmem_cache_create call in our net init method also seems to be
responsible for this lockdep warning:

[   45.163710] Unable to find swap-space signature
[   45.375718] trinity-c1 (855): attempted to duplicate a private mapping with mremap.  This is not supported.
[   46.055744] futex_wake_op: trinity-c1 tries to shift op by -209; fix this program
[   51.011723]
[   51.013378] ======================================================
[   51.013875] WARNING: possible circular locking dependency detected
[   51.014378] 5.2.0-rc2 #1 Not tainted
[   51.014672] ------------------------------------------------------
[   51.015182] trinity-c2/886 is trying to acquire lock:
[   51.015593] 000000005405f099 (slab_mutex){+.+.}, at: slab_attr_store+0xa2/0x130
[   51.016190]
[   51.016190] but task is already holding lock:
[   51.016652] 00000000ac662005 (kn->count#43){++++}, at: kernfs_fop_write+0x286/0x500
[   51.017266]
[   51.017266] which lock already depends on the new lock.
[   51.017266]
[   51.017909]
[   51.017909] the existing dependency chain (in reverse order) is:
[   51.018497]
[   51.018497] -> #1 (kn->count#43){++++}:
[   51.018956]        __lock_acquire+0x7cf/0x1a20
[   51.019317]        lock_acquire+0x17d/0x390
[   51.019658]        __kernfs_remove+0x892/0xae0
[   51.020020]        kernfs_remove_by_name_ns+0x78/0x110
[   51.020435]        sysfs_remove_link+0x55/0xb0
[   51.020832]        sysfs_slab_add+0xc1/0x3e0
[   51.021332]        __kmem_cache_create+0x155/0x200
[   51.021720]        create_cache+0xf5/0x320
[   51.022054]        kmem_cache_create_usercopy+0x179/0x320
[   51.022486]        kmem_cache_create+0x1a/0x30
[   51.022867]        nfsd_reply_cache_init+0x278/0x560
[   51.023266]        nfsd_init_net+0x20f/0x5e0
[   51.023623]        ops_init+0xcb/0x4b0
[   51.023928]        setup_net+0x2fe/0x670
[   51.024315]        copy_net_ns+0x30a/0x3f0
[   51.024653]        create_new_namespaces+0x3c5/0x820
[   51.025257]        unshare_nsproxy_namespaces+0xd1/0x240
[   51.025881]        ksys_unshare+0x506/0x9c0
[   51.026381]        __x64_sys_unshare+0x3a/0x50
[   51.026937]        do_syscall_64+0x110/0x10b0
[   51.027509]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   51.028175]
[   51.028175] -> #0 (slab_mutex){+.+.}:
[   51.028817]        validate_chain+0x1c51/0x2cc0
[   51.029422]        __lock_acquire+0x7cf/0x1a20
[   51.029947]        lock_acquire+0x17d/0x390
[   51.030438]        __mutex_lock+0x100/0xfa0
[   51.030995]        mutex_lock_nested+0x27/0x30
[   51.031516]        slab_attr_store+0xa2/0x130
[   51.032020]        sysfs_kf_write+0x11d/0x180
[   51.032529]        kernfs_fop_write+0x32a/0x500
[   51.033056]        do_loop_readv_writev+0x21d/0x310
[   51.033627]        do_iter_write+0x2e5/0x380
[   51.034148]        vfs_writev+0x170/0x310
[   51.034616]        do_pwritev+0x13e/0x160
[   51.035100]        __x64_sys_pwritev+0xa3/0x110
[   51.035633]        do_syscall_64+0x110/0x10b0
[   51.036200]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   51.036924]
[   51.036924] other info that might help us debug this:
[   51.036924]
[   51.037876]  Possible unsafe locking scenario:
[   51.037876]
[   51.038556]        CPU0                    CPU1
[   51.039130]        ----                    ----
[   51.039676]   lock(kn->count#43);
[   51.040084]                                lock(slab_mutex);
[   51.040597]                                lock(kn->count#43);
[   51.041062]   lock(slab_mutex);
[   51.041320]
[   51.041320]  *** DEADLOCK ***
[   51.041320]
[   51.041793] 3 locks held by trinity-c2/886:
[   51.042128]  #0: 000000001f55e152 (sb_writers#5){.+.+}, at: vfs_writev+0x2b9/0x310
[   51.042739]  #1: 00000000c7d6c034 (&of->mutex){+.+.}, at: kernfs_fop_write+0x25b/0x500
[   51.043400]  #2: 00000000ac662005 (kn->count#43){++++}, at: kernfs_fop_write+0x286/0x500

Reported-by: kernel test robot <lkp@intel.com>
Fixes: 3ba75830ce "drc containerization"
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-06-01 17:44:45 -04:00
Linus Torvalds 81e8c10dac Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto updates from Herbert Xu:
 "API:
   - Introduce crypto_shash_tfm_digest() and use it wherever possible.
   - Fix use-after-free and race in crypto_spawn_alg.
   - Add support for parallel and batch requests to crypto_engine.

  Algorithms:
   - Update jitter RNG for SP800-90B compliance.
   - Always use jitter RNG as seed in drbg.

  Drivers:
   - Add Arm CryptoCell driver cctrng.
   - Add support for SEV-ES to the PSP driver in ccp"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (114 commits)
  crypto: hisilicon - fix driver compatibility issue with different versions of devices
  crypto: engine - do not requeue in case of fatal error
  crypto: cavium/nitrox - Fix a typo in a comment
  crypto: hisilicon/qm - change debugfs file name from qm_regs to regs
  crypto: hisilicon/qm - add DebugFS for xQC and xQE dump
  crypto: hisilicon/zip - add debugfs for Hisilicon ZIP
  crypto: hisilicon/hpre - add debugfs for Hisilicon HPRE
  crypto: hisilicon/sec2 - add debugfs for Hisilicon SEC
  crypto: hisilicon/qm - add debugfs to the QM state machine
  crypto: hisilicon/qm - add debugfs for QM
  crypto: stm32/crc32 - protect from concurrent accesses
  crypto: stm32/crc32 - don't sleep in runtime pm
  crypto: stm32/crc32 - fix multi-instance
  crypto: stm32/crc32 - fix run-time self test issue.
  crypto: stm32/crc32 - fix ext4 chksum BUG_ON()
  crypto: hisilicon/zip - Use temporary sqe when doing work
  crypto: hisilicon - add device error report through abnormal irq
  crypto: hisilicon - remove codes of directly report device errors through MSI
  crypto: hisilicon - QM memory management optimization
  crypto: hisilicon - unify initial value assignment into QM
  ...
2020-06-01 12:00:10 -07:00
Xiyu Yang a4abc6b12e nfsd: Fix svc_xprt refcnt leak when setup callback client failed
nfsd4_process_cb_update() invokes svc_xprt_get(), which increases the
refcount of the "c->cn_xprt".

The reference counting issue happens in one exception handling path of
nfsd4_process_cb_update(). When setup callback client failed, the
function forgets to decrease the refcnt increased by svc_xprt_get(),
causing a refcnt leak.

Fix this issue by calling svc_xprt_put() when setup callback client
failed.

Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-05-28 18:15:00 -04:00
J. Bruce Fields 6670ee2ef2 Merge branch 'nfsd-5.8' of git://linux-nfs.org/~cel/cel-2.6 into for-5.8-incoming
Highlights of this series:
* Remove serialization of sending RPC/RDMA Replies
* Convert the TCP socket send path to use xdr_buf::bvecs (pre-requisite for
RPC-on-TLS)
* Fix svcrdma backchannel sendto return code
* Convert a number of dprintk call sites to use tracepoints
* Fix the "suggest braces around empty body in an 'else' statement" warning
2020-05-21 10:58:15 -04:00
Chuck Lever f2453978a4 NFSD: Fix improperly-formatted Doxygen comments
fs/nfsd/nfsctl.c:256: warning: Function parameter or member 'file' not described in 'write_unlock_ip'
fs/nfsd/nfsctl.c:256: warning: Function parameter or member 'buf' not described in 'write_unlock_ip'
fs/nfsd/nfsctl.c:256: warning: Function parameter or member 'size' not described in 'write_unlock_ip'
fs/nfsd/nfsctl.c:295: warning: Function parameter or member 'file' not described in 'write_unlock_fs'
fs/nfsd/nfsctl.c:295: warning: Function parameter or member 'buf' not described in 'write_unlock_fs'
fs/nfsd/nfsctl.c:295: warning: Function parameter or member 'size' not described in 'write_unlock_fs'
fs/nfsd/nfsctl.c:352: warning: Function parameter or member 'file' not described in 'write_filehandle'
fs/nfsd/nfsctl.c:352: warning: Function parameter or member 'buf' not described in 'write_filehandle'
fs/nfsd/nfsctl.c:352: warning: Function parameter or member 'size' not described in 'write_filehandle'
fs/nfsd/nfsctl.c:434: warning: Function parameter or member 'file' not described in 'write_threads'
fs/nfsd/nfsctl.c:434: warning: Function parameter or member 'buf' not described in 'write_threads'
fs/nfsd/nfsctl.c:434: warning: Function parameter or member 'size' not described in 'write_threads'
fs/nfsd/nfsctl.c:478: warning: Function parameter or member 'file' not described in 'write_pool_threads'
fs/nfsd/nfsctl.c:478: warning: Function parameter or member 'buf' not described in 'write_pool_threads'
fs/nfsd/nfsctl.c:478: warning: Function parameter or member 'size' not described in 'write_pool_threads'
fs/nfsd/nfsctl.c:697: warning: Function parameter or member 'file' not described in 'write_versions'
fs/nfsd/nfsctl.c:697: warning: Function parameter or member 'buf' not described in 'write_versions'
fs/nfsd/nfsctl.c:697: warning: Function parameter or member 'size' not described in 'write_versions'
fs/nfsd/nfsctl.c:858: warning: Function parameter or member 'file' not described in 'write_ports'
fs/nfsd/nfsctl.c:858: warning: Function parameter or member 'buf' not described in 'write_ports'
fs/nfsd/nfsctl.c:858: warning: Function parameter or member 'size' not described in 'write_ports'
fs/nfsd/nfsctl.c:892: warning: Function parameter or member 'file' not described in 'write_maxblksize'
fs/nfsd/nfsctl.c:892: warning: Function parameter or member 'buf' not described in 'write_maxblksize'
fs/nfsd/nfsctl.c:892: warning: Function parameter or member 'size' not described in 'write_maxblksize'
fs/nfsd/nfsctl.c:941: warning: Function parameter or member 'file' not described in 'write_maxconn'
fs/nfsd/nfsctl.c:941: warning: Function parameter or member 'buf' not described in 'write_maxconn'
fs/nfsd/nfsctl.c:941: warning: Function parameter or member 'size' not described in 'write_maxconn'
fs/nfsd/nfsctl.c:1023: warning: Function parameter or member 'file' not described in 'write_leasetime'
fs/nfsd/nfsctl.c:1023: warning: Function parameter or member 'buf' not described in 'write_leasetime'
fs/nfsd/nfsctl.c:1023: warning: Function parameter or member 'size' not described in 'write_leasetime'
fs/nfsd/nfsctl.c:1039: warning: Function parameter or member 'file' not described in 'write_gracetime'
fs/nfsd/nfsctl.c:1039: warning: Function parameter or member 'buf' not described in 'write_gracetime'
fs/nfsd/nfsctl.c:1039: warning: Function parameter or member 'size' not described in 'write_gracetime'
fs/nfsd/nfsctl.c:1094: warning: Function parameter or member 'file' not described in 'write_recoverydir'
fs/nfsd/nfsctl.c:1094: warning: Function parameter or member 'buf' not described in 'write_recoverydir'
fs/nfsd/nfsctl.c:1094: warning: Function parameter or member 'size' not described in 'write_recoverydir'
fs/nfsd/nfsctl.c:1125: warning: Function parameter or member 'file' not described in 'write_v4_end_grace'
fs/nfsd/nfsctl.c:1125: warning: Function parameter or member 'buf' not described in 'write_v4_end_grace'
fs/nfsd/nfsctl.c:1125: warning: Function parameter or member 'size' not described in 'write_v4_end_grace'

fs/nfsd/nfs4proc.c:1164: warning: Function parameter or member 'nss' not described in 'nfsd4_interssc_connect'
fs/nfsd/nfs4proc.c:1164: warning: Function parameter or member 'rqstp' not described in 'nfsd4_interssc_connect'
fs/nfsd/nfs4proc.c:1164: warning: Function parameter or member 'mount' not described in 'nfsd4_interssc_connect'
fs/nfsd/nfs4proc.c:1262: warning: Function parameter or member 'rqstp' not described in 'nfsd4_setup_inter_ssc'
fs/nfsd/nfs4proc.c:1262: warning: Function parameter or member 'cstate' not described in 'nfsd4_setup_inter_ssc'
fs/nfsd/nfs4proc.c:1262: warning: Function parameter or member 'copy' not described in 'nfsd4_setup_inter_ssc'
fs/nfsd/nfs4proc.c:1262: warning: Function parameter or member 'mount' not described in 'nfsd4_setup_inter_ssc'

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-05-20 17:30:44 -04:00
Chuck Lever 45f56da822 NFSD: Squash an annoying compiler warning
Clean up: Fix gcc empty-body warning when -Wextra is used.

../fs/nfsd/nfs4state.c:3898:3: warning: suggest braces around empty body in an ‘else’ statement [-Wempty-body]

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-05-20 17:30:44 -04:00
Chuck Lever 1eace0d1e9 NFSD: Add tracepoints for monitoring NFSD callbacks
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-05-20 17:30:44 -04:00
Chuck Lever dd5e3fbc1f NFSD: Add tracepoints to the NFSD state management code
Capture obvious events and replace dprintk() call sites. Introduce
infrastructure so that adding more tracepoints in this code later
is simplified.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-05-20 17:30:44 -04:00
Chuck Lever 0b175b1864 NFSD: Add tracepoints to NFSD's duplicate reply cache
Try to capture DRC failures.

Two additional clean-ups:
- Introduce Doxygen-style comments for the main entry points
- Remove a dprintk that fires for an allocation failure. This was
  the only dprintk in the REPCACHE class.

Reported-by: kbuild test robot <lkp@intel.com>
[ cel: force typecast for display of checksum values ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-05-20 17:30:34 -04:00
Ma Feng 44fb26c6b4 nfsd: Fix old-style function definition
Fix warning:

fs/nfsd/nfssvc.c:604:6: warning: old-style function definition [-Wold-style-definition]
 bool i_am_nfsd()
      ^~~~~~~~~

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Ma Feng <mafeng.ma@huawei.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-05-11 09:16:14 -04:00
J. Bruce Fields 28df3d1539 nfsd: clients don't need to break their own delegations
We currently revoke read delegations on any write open or any operation
that modifies file data or metadata (including rename, link, and
unlink).  But if the delegation in question is the only read delegation
and is held by the client performing the operation, that's not really
necessary.

It's not always possible to prevent this in the NFSv4.0 case, because
there's not always a way to determine which client an NFSv4.0 delegation
came from.  (In theory we could try to guess this from the transport
layer, e.g., by assuming all traffic on a given TCP connection comes
from the same client.  But that's not really correct.)

In the NFSv4.1 case the session layer always tells us the client.

This patch should remove such self-conflicts in all cases where we can
reliably determine the client from the compound.

To do that we need to track "who" is performing a given (possibly
lease-breaking) file operation.  We're doing that by storing the
information in the svc_rqst and using kthread_data() to map the current
task back to a svc_rqst.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-05-08 21:23:10 -04:00
Eric Biggers ea794db264 nfsd: use crypto_shash_tfm_digest()
Instead of manually allocating a 'struct shash_desc' on the stack and
calling crypto_shash_digest(), switch to using the new helper function
crypto_shash_tfm_digest() which does this for us.

Cc: linux-nfs@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-05-08 15:32:15 +10:00
J. Bruce Fields c2d715a1af nfsd: handle repeated BIND_CONN_TO_SESSION
If the client attempts BIND_CONN_TO_SESSION on an already bound
connection, it should be either a no-op or an error.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-05-06 15:59:23 -04:00
Achilles Gaikwad 580da465a0 nfsd4: add filename to states output
Add filename to states output for ease of debugging.

Signed-off-by: Achilles Gaikwad <agaikwad@redhat.com>
Signed-off-by: Kenneth Dsouza <kdsouza@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-05-06 15:59:23 -04:00
J. Bruce Fields ee590d2597 nfsd4: stid display should preserve on-the-wire byte order
When we decode the stateid we byte-swap si_generation.

But for simplicity's sake and ease of comparison with network traces,
it's better to display the whole thing in network order.

Reported-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-05-06 15:59:23 -04:00
J. Bruce Fields ace7ade4f5 nfsd4: common stateid-printing code
There's a problem with how I'm formatting stateids.  Before I fix it,
I'd like to move the stateid formatting into a common helper.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-05-06 15:59:23 -04:00
Chuck Lever 6221f1d9b6 SUNRPC: Fix backchannel RPC soft lockups
Currently, after the forward channel connection goes away,
backchannel operations are causing soft lockups on the server
because call_transmit_status's SOFTCONN logic ignores ENOTCONN.
Such backchannel Calls are aggressively retried until the client
reconnects.

Backchannel Calls should use RPC_TASK_NOCONNECT rather than
RPC_TASK_SOFTCONN. If there is no forward connection, the server is
not capable of establishing a connection back to the client, thus
that backchannel request should fail before the server attempts to
send it. Commit 58255a4e3c ("NFSD: NFSv4 callback client should
use RPC_TASK_SOFTCONN") was merged several years before
RPC_TASK_NOCONNECT was available.

Because setup_callback_client() explicitly sets NOPING, the NFSv4.0
callback connection depends on the first callback RPC to initiate
a connection to the client. Thus NFSv4.0 needs to continue to use
RPC_TASK_SOFTCONN.

Suggested-by: Trond Myklebust <trondmy@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: <stable@vger.kernel.org> # v4.20+
2020-04-17 12:40:31 -04:00
Vasily Averin e1e8399eee nfsd: memory corruption in nfsd4_lock()
New struct nfsd4_blocked_lock allocated in find_or_allocate_block()
does not initialized nbl_list and nbl_lru.
If conflock allocation fails rollback can call list_del_init()
access uninitialized fields and corrupt memory.

v2: just initialize nbl_list and nbl_lru right after nbl allocation.

Fixes: 76d348fadf ("nfsd: have nfsd4_lock use blocking locks for v4.1+ lock")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-04-13 10:28:21 -04:00
J. Bruce Fields 69afd26798 nfsd: fsnotify on rmdir under nfsd/clients/
Userspace should be able to monitor nfsd/clients/ to see when clients
come and go, but we're failing to send fsnotify events.

Cc: stable@kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-19 11:33:42 -04:00
J. Bruce Fields 663e36f076 nfsd4: kill warnings on testing stateids with mismatched clientids
It's normal for a client to test a stateid from a previous instance,
e.g. after a network partition.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-19 10:51:42 -04:00
Petr Vorel 6cbfad5f20 nfsd: remove read permission bit for ctl sysctl
It's meant to be write-only.

Fixes: 89c905becc ("nfsd: allow forced expiration of NFSv4 clients")
Signed-off-by: Petr Vorel <pvorel@suse.cz>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16 12:04:34 -04:00
Chuck Lever 3ac3711adb NFSD: Fix NFS server build errors
yuehaibing@huawei.com reports the following build errors arise when
CONFIG_NFSD_V4_2_INTER_SSC is set and the NFS client is not built
into the kernel:

fs/nfsd/nfs4proc.o: In function `nfsd4_do_copy':
nfs4proc.c:(.text+0x23b7): undefined reference to `nfs42_ssc_close'
fs/nfsd/nfs4proc.o: In function `nfsd4_copy':
nfs4proc.c:(.text+0x5d2a): undefined reference to `nfs_sb_deactive'
fs/nfsd/nfs4proc.o: In function `nfsd4_do_async_copy':
nfs4proc.c:(.text+0x61d5): undefined reference to `nfs42_ssc_open'
nfs4proc.c:(.text+0x6389): undefined reference to `nfs_sb_deactive'

The new inter-server copy code invokes client functions. Until the
NFS server has infrastructure to load the appropriate NFS client
modules to handle inter-server copy requests, let's constrain the
way this feature is built.

Reported-by: YueHaibing <yuehaibing@huawei.com>
Fixes: ce0887ac96 ("NFSD add nfs4 inter ssc to nfsd4_copy")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: YueHaibing <yuehaibing@huawei.com> # build-tested
2020-03-16 12:04:34 -04:00
Trond Myklebust 65286b883c nfsd: export upcalls must not return ESTALE when mountd is down
If the rpc.mountd daemon goes down, then that should not cause all
exports to start failing with ESTALE errors. Let's explicitly
distinguish between the cache upcall cases that need to time out,
and those that do not.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16 12:04:33 -04:00
Trond Myklebust 6a30e47fa0 nfsd: Add tracepoints for update of the expkey and export cache entries
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16 12:04:33 -04:00
Trond Myklebust cf749f3cc7 nfsd: Add tracepoints for exp_find_key() and exp_get_by_name()
Add tracepoints for upcalls.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16 12:04:33 -04:00
Trond Myklebust f01274a933 nfsd: Add tracing to nfsd_set_fh_dentry()
Add tracing to allow us to figure out where any stale filehandle issues
may be originating from.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16 12:04:33 -04:00
Trond Myklebust a451b12311 nfsd: Don't add locks to closed or closing open stateids
In NFSv4, the lock stateids are tied to the lockowner, and the open stateid,
so that the action of closing the file also results in either an automatic
loss of the locks, or an error of the form NFS4ERR_LOCKS_HELD.

In practice this means we must not add new locks to the open stateid
after the close process has been invoked. In fact doing so, can result
in the following panic:

 kernel BUG at lib/list_debug.c:51!
 invalid opcode: 0000 [#1] SMP NOPTI
 CPU: 2 PID: 1085 Comm: nfsd Not tainted 5.6.0-rc3+ #2
 Hardware name: VMware, Inc. VMware7,1/440BX Desktop Reference Platform, BIOS VMW71.00V.14410784.B64.1908150010 08/15/2019
 RIP: 0010:__list_del_entry_valid.cold+0x31/0x55
 Code: 1a 3d 9b e8 74 10 c2 ff 0f 0b 48 c7 c7 f0 1a 3d 9b e8 66 10 c2 ff 0f 0b 48 89 f2 48 89 fe 48 c7 c7 b0 1a 3d 9b e8 52 10 c2 ff <0f> 0b 48 89 fe 4c 89 c2 48 c7 c7 78 1a 3d 9b e8 3e 10 c2 ff 0f 0b
 RSP: 0018:ffffb296c1d47d90 EFLAGS: 00010246
 RAX: 0000000000000054 RBX: ffff8ba032456ec8 RCX: 0000000000000000
 RDX: 0000000000000000 RSI: ffff8ba039e99cc8 RDI: ffff8ba039e99cc8
 RBP: ffff8ba032456e60 R08: 0000000000000781 R09: 0000000000000003
 R10: 0000000000000000 R11: 0000000000000001 R12: ffff8ba009a4abe0
 R13: ffff8ba032456e8c R14: 0000000000000000 R15: ffff8ba00adb01d8
 FS:  0000000000000000(0000) GS:ffff8ba039e80000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007fb213f0b008 CR3: 00000001347de006 CR4: 00000000003606e0
 Call Trace:
  release_lock_stateid+0x2b/0x80 [nfsd]
  nfsd4_free_stateid+0x1e9/0x210 [nfsd]
  nfsd4_proc_compound+0x414/0x700 [nfsd]
  ? nfs4svc_decode_compoundargs+0x407/0x4c0 [nfsd]
  nfsd_dispatch+0xc1/0x200 [nfsd]
  svc_process_common+0x476/0x6f0 [sunrpc]
  ? svc_sock_secure_port+0x12/0x30 [sunrpc]
  ? svc_recv+0x313/0x9c0 [sunrpc]
  ? nfsd_svc+0x2d0/0x2d0 [nfsd]
  svc_process+0xd4/0x110 [sunrpc]
  nfsd+0xe3/0x140 [nfsd]
  kthread+0xf9/0x130
  ? nfsd_destroy+0x50/0x50 [nfsd]
  ? kthread_park+0x90/0x90
  ret_from_fork+0x1f/0x40

The fix is to ensure that lock creation tests for whether or not the
open stateid is unhashed, and to fail if that is the case.

Fixes: 659aefb68e ("nfsd: Ensure we don't recognise lock stateids after freeing them")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16 12:04:33 -04:00
Chuck Lever 7dcf4ab952 NFSD: Clean up nfsd4_encode_readv
Address some minor nits I noticed while working on this function.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16 12:04:31 -04:00
Chuck Lever 412055398b nfsd: Fix NFSv4 READ on RDMA when using readv
svcrdma expects that the payload falls precisely into the xdr_buf
page vector. This does not seem to be the case for
nfsd4_encode_readv().

This code is called only when fops->splice_read is missing or when
RQ_SPLICE_OK is clear, so it's not a noticeable problem in many
common cases.

Add new transport method: ->xpo_read_payload so that when a READ
payload does not fit exactly in rq_res's page vector, the XDR
encoder can inform the RPC transport exactly where that payload is,
without the payload's XDR pad.

That way, when a Write chunk is present, the transport knows what
byte range in the Reply message is supposed to be matched with the
chunk.

Note that the Linux NFS server implementation of NFS/RDMA can
currently handle only one Write chunk per RPC-over-RDMA message.
This simplifies the implementation of this fix.

Fixes: b042098063 ("nfsd4: allow exotic read compounds")
Buglink: https://bugzilla.kernel.org/show_bug.cgi?id=198053
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16 12:04:31 -04:00
Madhuparna Bhowmik 057a227435 fs: nfsd: fileache.c: Use built-in RCU list checking
list_for_each_entry_rcu() has built-in RCU and lock checking.

Pass cond argument to list_for_each_entry_rcu() to silence
false lockdep warning when  CONFIG_PROVE_RCU_LIST is enabled
by default.

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16 12:04:31 -04:00
Madhuparna Bhowmik 36a8049181 fs: nfsd: nfs4state.c: Use built-in RCU list checking
list_for_each_entry_rcu() has built-in RCU and lock checking.

Pass cond argument to list_for_each_entry_rcu() to silence
false lockdep warning when  CONFIG_PROVE_RCU_LIST is enabled
by default.

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16 12:04:31 -04:00
Scott Mayhew 7627d7dc79 nfsd: set the server_scope during service startup
Currently, nfsd4_encode_exchange_id() encodes the utsname nodename
string in the server_scope field.  In a multi-host container
environemnt, if an nfsd container is restarted on a different host than
it was originally running on, clients will see a server_scope mismatch
and will not attempt to reclaim opens.

Instead, set the server_scope while we're in a process context during
service startup, so we get the utsname nodename of the current process
and store that in nfsd_net.

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
[bfields: fix up major_id too]
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-03-16 12:04:30 -04:00
Linus Torvalds 08dffcc7d9 Highlights:
- Server-to-server copy code from Olga.  To use it, client and
 	  both servers must have support, the target server must be able
 	  to access the source server over NFSv4.2, and the target
 	  server must have the inter_copy_offload_enable module
 	  parameter set.
 	- Improvements and bugfixes for the new filehandle cache,
 	  especially in the container case, from Trond
 	- Also from Trond, better reporting of write errors.
 	- Y2038 work from Arnd.
 -----BEGIN PGP SIGNATURE-----
 
 iQJJBAABCAAzFiEEYtFWavXG9hZotryuJ5vNeUKO4b4FAl490mAVHGJmaWVsZHNA
 ZmllbGRzZXMub3JnAAoJECebzXlCjuG+HkkP/33CsYXp0wvfNrfxCY3zHRxHpfw+
 T9Ownxxw0RAJc/dRluC/2PIKJ20uVqtLrplU63bMBqJn84WF7OALq9twZ79a3fVF
 mvdmnZbNq9B3ncKJlT7akkEelyJCRap7NgG/oTyubE8MlPl6gKpD8c+G7XdW/uN+
 r0fprQz4rW4CYCBGSHq7HusEKqY4Gw+gbyAfJ6A79TMjF1ei51PG+9c8rkIsI5CO
 1TQ3gY1gSJmGf2DoF86Q9WTVb+DvRTEs+t7QkxY/Vlo+QXY8CZyu+qSxN7i/F20m
 gv2GrSpQMS9DEK/ZaG6cxaH+sM18Db4KLvcl3koL6lONHDR2OafSdKLyy0I60jhO
 WfDSHhfDCrAdASTjNlTPrjBrdK3gafiaJVL9vy901ZJjPaNb3EH0nMQ5bEvOBECq
 TCqPcQUcbku+qUVIcFwzSK1hXQFQHNh8WIuqXvNviZIzFDoipwsHVnQK02Owj89L
 R2tbZue1O8voacg/9xw3tWAT7pI+SaBb0EvJuqRxBshiZEU8kKKtMchOwSECRDcu
 k4lcqC5EFW7e4EzGlr6Wx8sI5lwCapva8ccjmPXX+R/vyM81oxWGB84GqWjjwubH
 3Fcok23F9rW2IQJkqgPlNj/9hAjTn2+vM13UbfMlnchGNsQ2gbkc5CDGC/J6Wwpo
 tHVristV9Gu5bJym
 =FxLY
 -----END PGP SIGNATURE-----

Merge tag 'nfsd-5.6' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "Highlights:

   - Server-to-server copy code from Olga.

     To use it, client and both servers must have support, the target
     server must be able to access the source server over NFSv4.2, and
     the target server must have the inter_copy_offload_enable module
     parameter set.

   - Improvements and bugfixes for the new filehandle cache, especially
     in the container case, from Trond

   - Also from Trond, better reporting of write errors.

   - Y2038 work from Arnd"

* tag 'nfsd-5.6' of git://linux-nfs.org/~bfields/linux: (55 commits)
  sunrpc: expiry_time should be seconds not timeval
  nfsd: make nfsd_filecache_wq variable static
  nfsd4: fix double free in nfsd4_do_async_copy()
  nfsd: convert file cache to use over/underflow safe refcount
  nfsd: Define the file access mode enum for tracing
  nfsd: Fix a perf warning
  nfsd: Ensure sampling of the write verifier is atomic with the write
  nfsd: Ensure sampling of the commit verifier is atomic with the commit
  sunrpc: clean up cache entry add/remove from hashtable
  sunrpc: Fix potential leaks in sunrpc_cache_unhash()
  nfsd: Ensure exclusion between CLONE and WRITE errors
  nfsd: Pass the nfsd_file as arguments to nfsd4_clone_file_range()
  nfsd: Update the boot verifier on stable writes too.
  nfsd: Fix stable writes
  nfsd: Allow nfsd_vfs_write() to take the nfsd_file as an argument
  nfsd: Fix a soft lockup race in nfsd_file_mark_find_or_create()
  nfsd: Reduce the number of calls to nfsd_file_gc()
  nfsd: Schedule the laundrette regularly irrespective of file errors
  nfsd: Remove unused constant NFSD_FILE_LRU_RESCAN
  nfsd: Containerise filecache laundrette
  ...
2020-02-07 17:50:21 -08:00
Chen Zhou 50d0def966 nfsd: make nfsd_filecache_wq variable static
Fix sparse warning:

fs/nfsd/filecache.c:55:25: warning:
	symbol 'nfsd_filecache_wq' was not declared. Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-02-07 13:30:41 -05:00
Dan Carpenter 91fd3c3edc nfsd4: fix double free in nfsd4_do_async_copy()
This frees "copy->nf_src" before and again after the goto.

Fixes: ce0887ac96 ("NFSD add nfs4 inter ssc to nfsd4_copy")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-02-06 11:22:55 -05:00
Trond Myklebust 689827cd5b nfsd: convert file cache to use over/underflow safe refcount
Use the 'refcount_t' type instead of 'atomic_t' for improved
refcounting safety.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-02-06 11:22:55 -05:00
Trond Myklebust c19285596d nfsd: Define the file access mode enum for tracing
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-02-06 11:22:55 -05:00
Trond Myklebust a9ceb060b3 nfsd: Fix a perf warning
perf does not know how to deal with a __builtin_bswap32() call, and
complains. All other functions just store the xid etc in host endian
form, so let's do that in the tracepoint for nfsd_file_acquire too.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-02-06 11:22:54 -05:00
Alexey Dobriyan 97a32539b9 proc: convert everything to "struct proc_ops"
The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in
seq_file.h.

Conversion rule is:

	llseek		=> proc_lseek
	unlocked_ioctl	=> proc_ioctl

	xxx		=> proc_xxx

	delete ".owner = THIS_MODULE" line

[akpm@linux-foundation.org: fix drivers/isdn/capi/kcapi_proc.c]
[sfr@canb.auug.org.au: fix kernel/sched/psi.c]
  Link: http://lkml.kernel.org/r/20200122180545.36222f50@canb.auug.org.au
Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 03:05:26 +00:00
Trond Myklebust 19e0663ff9 nfsd: Ensure sampling of the write verifier is atomic with the write
When doing an unstable write, we need to ensure that we sample the
write verifier before releasing the lock, and allowing a commit to
the same file to proceed.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-01-22 16:25:41 -05:00
Trond Myklebust 524ff1af22 nfsd: Ensure sampling of the commit verifier is atomic with the commit
When we have a successful commit, ensure we sample the commit verifier
before releasing the lock.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-01-22 16:25:41 -05:00
Trond Myklebust 1b28d756b2 nfsd: Ensure exclusion between CLONE and WRITE errors
Ensure that we can distinguish between synchronous CLONE and
WRITE errors, and that we can assign them correctly.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-01-22 16:25:41 -05:00
Trond Myklebust b66ae6dd0c nfsd: Pass the nfsd_file as arguments to nfsd4_clone_file_range()
Needed in order to fix exclusion w.r.t. writes.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-01-22 16:25:40 -05:00
Trond Myklebust 7bf94c6ba9 nfsd: Update the boot verifier on stable writes too.
We don't know if the error returned by the fsync() call is
exclusive to the data written by the stable write, so play it
safe.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-01-22 16:25:40 -05:00
Trond Myklebust 5011af4c69 nfsd: Fix stable writes
Strictly speaking, a stable write error needs to reflect the
write + the commit of that write (and only that write). To
ensure that we don't pick up the write errors from other
writebacks, add a rw_semaphore to provide exclusion.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-01-22 16:25:40 -05:00
Trond Myklebust 16f8f89410 nfsd: Allow nfsd_vfs_write() to take the nfsd_file as an argument
Needed in order to fix stable writes.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-01-22 16:25:40 -05:00
Trond Myklebust 90d2f1da83 nfsd: Fix a soft lockup race in nfsd_file_mark_find_or_create()
If nfsd_file_mark_find_or_create() keeps winning the race for the
nfsd_file_fsnotify_group->mark_mutex against nfsd_file_mark_put()
then it can soft lock up, since fsnotify_add_inode_mark() ends
up always finding an existing entry.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-01-22 16:25:40 -05:00