Commit Graph

4932 Commits

Author SHA1 Message Date
NeilBrown
b688741cb0 NFS: revalidate "." etc correctly on "open".
For correct close-to-open semantics, NFS must validate
the change attribute of a directory (or file) on open.

Since commit ecf3d1f1aa ("vfs: kill FS_REVAL_DOT by adding a
d_weak_revalidate dentry op"), open() of "." or a path ending ".." is
not revalidated reliably (except when that direct is a mount point).

Prior to that commit, "." was revalidated using nfs_lookup_revalidate()
which checks the LOOKUP_OPEN flag and forces revalidation if the flag is
set.
Since that commit, nfs_weak_revalidate() is used for NFSv3 (which
ignores the flags) and nothing is used for NFSv4.

This is fixed by using nfs_lookup_verify_inode() in
nfs_weak_revalidate().  This does the revalidation exactly when needed.
Also, add a definition of .d_weak_revalidate for NFSv4.

The incorrect behavior is easily demonstrated by running "echo *" in
some non-mountpoint NFS directory while watching network traffic.
Without this patch, "echo *" sometimes doesn't produce any traffic.
With the patch it always does.

Fixes: ecf3d1f1aa ("vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op")
cc: stable@vger.kernel.org (3.9+)
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-10-16 13:51:27 -04:00
Anna Schumaker
1750d929b0 NFS: Don't compare apples to elephants to determine access bits
The NFS_ACCESS_* flags aren't a 1:1 mapping to the MAY_* flags, so
checking for MAY_WHATEVER might have surprising results in
nfs*_proc_access().  Let's simplify this check when determining which
bits to ask for, and do it in a generic place instead of copying code
for each NFS version.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-10-16 13:51:27 -04:00
Anna Schumaker
3c1818275c NFS: Create NFS_ACCESS_* flags
Passing the NFS v4 flags into the v3 code seems weird to me, even if
they are defined to the same values.  This patch adds in generic flags
to help me feel better

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
2017-10-16 13:51:27 -04:00
Trond Myklebust
e8fa33a6f6 NFSv4/pnfs: Fix an infinite layoutget loop
Since we can now use a lock stateid or a delegation stateid, that
differs from the context stateid, we need to change the test in
nfs4_layoutget_handle_exception() to take this into account.

This fixes an infinite layoutget loop in the NFS client whereby
it keeps retrying the initial layoutget using the same broken
stateid.

Fixes: 70d2f7b1ea ("pNFS: Use the standard I/O stateid when...")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-10-04 14:06:54 -04:00
Scott Mayhew
0a47df11bf nfs/filelayout: fix oops when freeing filelayout segment
Check for a NULL dsaddr in filelayout_free_lseg() before calling
nfs4_fl_put_deviceid().  This fixes the following oops:

[ 1967.645207] BUG: unable to handle kernel NULL pointer dereference at 0000000000000030
[ 1967.646010] IP: [<ffffffffc06d6aea>] nfs4_put_deviceid_node+0xa/0x90 [nfsv4]
[ 1967.646010] PGD c08bc067 PUD 915d3067 PMD 0
[ 1967.753036] Oops: 0000 [#1] SMP
[ 1967.753036] Modules linked in: nfs_layout_nfsv41_files ext4 mbcache jbd2 loop rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache amd64_edac_mod ipmi_ssif edac_mce_amd edac_core kvm_amd sg kvm ipmi_si ipmi_devintf irqbypass pcspkr k8temp ipmi_msghandler i2c_piix4 shpchp nfsd auth_rpcgss nfs_acl lockd grace sunrpc ip_tables xfs libcrc32c sd_mod crc_t10dif crct10dif_generic crct10dif_common amdkfd amd_iommu_v2 radeon i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops mptsas ttm scsi_transport_sas mptscsih drm mptbase serio_raw i2c_core bnx2 dm_mirror dm_region_hash dm_log dm_mod
[ 1967.790031] CPU: 2 PID: 1370 Comm: ls Not tainted 3.10.0-709.el7.test.bz1463784.x86_64 #1
[ 1967.790031] Hardware name: IBM BladeCenter LS21 -[7971AC1]-/Server Blade, BIOS -[BAE155AUS-1.10]- 06/03/2009
[ 1967.790031] task: ffff8800c42a3f40 ti: ffff8800c4064000 task.ti: ffff8800c4064000
[ 1967.790031] RIP: 0010:[<ffffffffc06d6aea>]  [<ffffffffc06d6aea>] nfs4_put_deviceid_node+0xa/0x90 [nfsv4]
[ 1967.790031] RSP: 0000:ffff8800c4067978  EFLAGS: 00010246
[ 1967.790031] RAX: ffffffffc062f000 RBX: ffff8801d468a540 RCX: dead000000000200
[ 1967.790031] RDX: ffff8800c40679f8 RSI: ffff8800c4067a0c RDI: 0000000000000000
[ 1967.790031] RBP: ffff8800c4067980 R08: ffff8801d468a540 R09: 0000000000000000
[ 1967.790031] R10: 0000000000000000 R11: ffffffffffffffff R12: ffff8801d468a540
[ 1967.790031] R13: ffff8800c40679f8 R14: ffff8801d5645300 R15: ffff880126f15ff0
[ 1967.790031] FS:  00007f11053c9800(0000) GS:ffff88012bd00000(0000) knlGS:0000000000000000
[ 1967.790031] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 1967.790031] CR2: 0000000000000030 CR3: 0000000094b55000 CR4: 00000000000007e0
[ 1967.790031] Stack:
[ 1967.790031]  ffff8801d468a540 ffff8800c4067990 ffffffffc062d2fe ffff8800c40679b0
[ 1967.790031]  ffffffffc062b5b4 ffff8800c40679f8 ffff8801d468a540 ffff8800c40679d8
[ 1967.790031]  ffffffffc06d39af ffff8800c40679f8 ffff880126f16078 0000000000000001
[ 1967.790031] Call Trace:
[ 1967.790031]  [<ffffffffc062d2fe>] nfs4_fl_put_deviceid+0xe/0x10 [nfs_layout_nfsv41_files]
[ 1967.790031]  [<ffffffffc062b5b4>] filelayout_free_lseg+0x24/0x90 [nfs_layout_nfsv41_files]
[ 1967.790031]  [<ffffffffc06d39af>] pnfs_free_lseg_list+0x5f/0x80 [nfsv4]
[ 1967.790031]  [<ffffffffc06d5a67>] _pnfs_return_layout+0x157/0x270 [nfsv4]
[ 1967.790031]  [<ffffffffc06c17dd>] nfs4_evict_inode+0x4d/0x70 [nfsv4]
[ 1967.790031]  [<ffffffff8121de19>] evict+0xa9/0x180
[ 1967.790031]  [<ffffffff8121e729>] iput+0xf9/0x190
[ 1967.790031]  [<ffffffffc0652cea>] nfs_dentry_iput+0x3a/0x50 [nfs]
[ 1967.790031]  [<ffffffff8121ab4f>] shrink_dentry_list+0x20f/0x490
[ 1967.790031]  [<ffffffff8121b018>] d_invalidate+0xd8/0x150
[ 1967.790031]  [<ffffffffc065446b>] nfs_readdir_page_filler+0x40b/0x600 [nfs]
[ 1967.790031]  [<ffffffffc0654bbd>] nfs_readdir_xdr_to_array+0x20d/0x3b0 [nfs]
[ 1967.790031]  [<ffffffff811f3482>] ? __mem_cgroup_commit_charge+0xe2/0x2f0
[ 1967.790031]  [<ffffffff81183208>] ? __add_to_page_cache_locked+0x48/0x170
[ 1967.790031]  [<ffffffffc0654d60>] ? nfs_readdir_xdr_to_array+0x3b0/0x3b0 [nfs]
[ 1967.790031]  [<ffffffffc0654d82>] nfs_readdir_filler+0x22/0x90 [nfs]
[ 1967.790031]  [<ffffffff8118351f>] do_read_cache_page+0x7f/0x190
[ 1967.790031]  [<ffffffff81215d30>] ? fillonedir+0xe0/0xe0
[ 1967.790031]  [<ffffffff8118366c>] read_cache_page+0x1c/0x30
[ 1967.790031]  [<ffffffffc0654f9b>] nfs_readdir+0x1ab/0x6b0 [nfs]
[ 1967.790031]  [<ffffffffc06bd1c0>] ? nfs4_xdr_dec_layoutget+0x270/0x270 [nfsv4]
[ 1967.790031]  [<ffffffff81215d30>] ? fillonedir+0xe0/0xe0
[ 1967.790031]  [<ffffffff81215c20>] vfs_readdir+0xb0/0xe0
[ 1967.790031]  [<ffffffff81216045>] SyS_getdents+0x95/0x120
[ 1967.790031]  [<ffffffff816b9449>] system_call_fastpath+0x16/0x1b
[ 1967.790031] Code: 90 31 d2 48 89 d0 5d c3 85 f6 74 f5 8d 4e 01 89 f0 f0 0f b1 0f 39 f0 74 e2 89 c6 eb eb 0f 1f 40 00 66 66 66 66 90 55 48 89 e5 53 <48> 8b 47 30 48 89 fb a8 04 74 3b 8b 57 60 83 fa 02 74 19 8d 4a
[ 1967.790031] RIP  [<ffffffffc06d6aea>] nfs4_put_deviceid_node+0xa/0x90 [nfsv4]
[ 1967.790031]  RSP <ffff8800c4067978>
[ 1967.790031] CR2: 0000000000000030

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Fixes: 1ebf980127 ("NFS/filelayout: Fix racy setting of fl->dsaddr...")
Cc: stable@vger.kernel.org # v4.13+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-10-01 18:51:30 -04:00
Benjamin Coddington
68ebf8fe3b NFS: Fix uninitialized rpc_wait_queue
Michael Sterrett reports a NULL pointer dereference on NFSv3 mounts when
CONFIG_NFS_V4 is not set because the NFS UOC rpc_wait_queue has not been
initialized.  Move the initialization of the queue out of the CONFIG_NFS_V4
conditional setion.

Fixes: 7d6ddf88c4 ("NFS: Add an iocounter wait function for async RPC tasks")
Cc: stable@vger.kernel.org # 4.11+
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-10-01 18:51:30 -04:00
Dan Carpenter
cdb2e53fd6 NFS: Cleanup error handling in nfs_idmap_request_key()
nfs_idmap_get_desc() can't actually return zero.  But if it did then
we would return ERR_PTR(0) which is NULL and the caller,
nfs_idmap_get_key(), doesn't expect that so it leads to a NULL pointer
dereference.

I've cleaned this up by changing the "<=" to "<" so it's more clear that
we don't return ERR_PTR(0).

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-10-01 18:51:30 -04:00
J. Bruce Fields
35c036ef4a nfs: RPC_MAX_AUTH_SIZE is in bytes
The units of RPC_MAX_AUTH_SIZE is bytes, not 4-byte words.  This causes
the client to request a larger-than-necessary session replay slot size.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-10-01 18:51:30 -04:00
Linus Torvalds
6ed0529fef NFS client bugfixes for Linux 4.14
Hightlights include:
 
 bugfixes:
 - Various changes relating to reporting IO errors.
 - pnfs: Use the standard I/O stateid when calling LAYOUTGET
 
 Features:
 - Add static NFS I/O tracepoints for debugging
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Merge tag 'nfs-for-4.14-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull more NFS client updates from Trond Myklebust:
 "Hightlights include:

  Bugfixes:
   - Various changes relating to reporting IO errors.
   - pnfs: Use the standard I/O stateid when calling LAYOUTGET

  Features:
   - Add static NFS I/O tracepoints for debugging"

* tag 'nfs-for-4.14-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFS: various changes relating to reporting IO errors.
  NFS: Add static NFS I/O tracepoints
  pNFS: Use the standard I/O stateid when calling LAYOUTGET
2017-09-14 20:04:32 -07:00
Linus Torvalds
0f0d12728e Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull mount flag updates from Al Viro:
 "Another chunk of fmount preparations from dhowells; only trivial
  conflicts for that part. It separates MS_... bits (very grotty
  mount(2) ABI) from the struct super_block ->s_flags (kernel-internal,
  only a small subset of MS_... stuff).

  This does *not* convert the filesystems to new constants; only the
  infrastructure is done here. The next step in that series is where the
  conflicts would be; that's the conversion of filesystems. It's purely
  mechanical and it's better done after the merge, so if you could run
  something like

	list=$(for i in MS_RDONLY MS_NOSUID MS_NODEV MS_NOEXEC MS_SYNCHRONOUS MS_MANDLOCK MS_DIRSYNC MS_NOATIME MS_NODIRATIME MS_SILENT MS_POSIXACL MS_KERNMOUNT MS_I_VERSION MS_LAZYTIME; do git grep -l $i fs drivers/staging/lustre drivers/mtd ipc mm include/linux; done|sort|uniq|grep -v '^fs/namespace.c$')

	sed -i -e 's/\<MS_RDONLY\>/SB_RDONLY/g' \
	        -e 's/\<MS_NOSUID\>/SB_NOSUID/g' \
	        -e 's/\<MS_NODEV\>/SB_NODEV/g' \
	        -e 's/\<MS_NOEXEC\>/SB_NOEXEC/g' \
	        -e 's/\<MS_SYNCHRONOUS\>/SB_SYNCHRONOUS/g' \
	        -e 's/\<MS_MANDLOCK\>/SB_MANDLOCK/g' \
	        -e 's/\<MS_DIRSYNC\>/SB_DIRSYNC/g' \
	        -e 's/\<MS_NOATIME\>/SB_NOATIME/g' \
	        -e 's/\<MS_NODIRATIME\>/SB_NODIRATIME/g' \
	        -e 's/\<MS_SILENT\>/SB_SILENT/g' \
	        -e 's/\<MS_POSIXACL\>/SB_POSIXACL/g' \
	        -e 's/\<MS_KERNMOUNT\>/SB_KERNMOUNT/g' \
	        -e 's/\<MS_I_VERSION\>/SB_I_VERSION/g' \
	        -e 's/\<MS_LAZYTIME\>/SB_LAZYTIME/g' \
	        $list

  and commit it with something along the lines of 'convert filesystems
  away from use of MS_... constants' as commit message, it would save a
  quite a bit of headache next cycle"

* 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  VFS: Differentiate mount flags (MS_*) from internal superblock flags
  VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb)
  vfs: Add sb_rdonly(sb) to query the MS_RDONLY flag on s_flags
2017-09-14 18:54:01 -07:00
Linus Torvalds
8e7757d83d NFS client updates for Linux 4.14
Hightlights include:
 
 Stable bugfixes:
 - Fix mirror allocation in the writeback code to avoid a use after free
 - Fix the O_DSYNC writes to use the correct byte range
 - Fix 2 use after free issues in the I/O code
 
 Features:
 - Writeback fixes to split up the inode->i_lock in order to reduce contention
 - RPC client receive fixes to reduce the amount of time the
   xprt->transport_lock is held when receiving data from a socket into am
   XDR buffer.
 - Ditto fixes to reduce contention between call side users of the rdma
   rb_lock, and its use in rpcrdma_reply_handler.
 - Re-arrange rdma stats to reduce false cacheline sharing.
 - Various rdma cleanups and optimisations.
 - Refactor the NFSv4.1 exchange id code and clean up the code.
 - Const-ify all instances of struct rpc_xprt_ops
 
 Bugfixes:
 - Fix the NFSv2 'sec=' mount option.
 - NFSv4.1: don't use machine credentials for CLOSE when using 'sec=sys'
 - Fix the NFSv3 GRANT callback when the port changes on the server.
 - Fix livelock issues with COMMIT
 - NFSv4: Use correct inode in _nfs4_opendata_to_nfs4_state() when doing
   and NFSv4.1 open by filehandle.
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Merge tag 'nfs-for-4.14-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client updates from Trond Myklebust:
 "Hightlights include:

  Stable bugfixes:
   - Fix mirror allocation in the writeback code to avoid a use after
     free
   - Fix the O_DSYNC writes to use the correct byte range
   - Fix 2 use after free issues in the I/O code

  Features:
   - Writeback fixes to split up the inode->i_lock in order to reduce
     contention
   - RPC client receive fixes to reduce the amount of time the
     xprt->transport_lock is held when receiving data from a socket into
     am XDR buffer.
   - Ditto fixes to reduce contention between call side users of the
     rdma rb_lock, and its use in rpcrdma_reply_handler.
   - Re-arrange rdma stats to reduce false cacheline sharing.
   - Various rdma cleanups and optimisations.
   - Refactor the NFSv4.1 exchange id code and clean up the code.
   - Const-ify all instances of struct rpc_xprt_ops

  Bugfixes:
   - Fix the NFSv2 'sec=' mount option.
   - NFSv4.1: don't use machine credentials for CLOSE when using
     'sec=sys'
   - Fix the NFSv3 GRANT callback when the port changes on the server.
   - Fix livelock issues with COMMIT
   - NFSv4: Use correct inode in _nfs4_opendata_to_nfs4_state() when
     doing and NFSv4.1 open by filehandle"

* tag 'nfs-for-4.14-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (69 commits)
  NFS: Count the bytes of skipped subrequests in nfs_lock_and_join_requests()
  NFS: Don't hold the group lock when calling nfs_release_request()
  NFS: Remove pnfs_generic_transfer_commit_list()
  NFS: nfs_lock_and_join_requests and nfs_scan_commit_list can deadlock
  NFS: Fix 2 use after free issues in the I/O code
  NFS: Sync the correct byte range during synchronous writes
  lockd: Delete an error message for a failed memory allocation in reclaimer()
  NFS: remove jiffies field from access cache
  NFS: flush data when locking a file to ensure cache coherence for mmap.
  SUNRPC: remove some dead code.
  NFS: don't expect errors from mempool_alloc().
  xprtrdma: Use xprt_pin_rqst in rpcrdma_reply_handler
  xprtrdma: Re-arrange struct rx_stats
  NFS: Fix NFSv2 security settings
  NFSv4.1: don't use machine credentials for CLOSE when using 'sec=sys'
  SUNRPC: ECONNREFUSED should cause a rebind.
  NFS: Remove unused parameter gfp_flags from nfs_pageio_init()
  NFSv4: Fix up mirror allocation
  SUNRPC: Add a separate spinlock to protect the RPC request receive list
  SUNRPC: Cleanup xs_tcp_read_common()
  ...
2017-09-11 22:01:44 -07:00
NeilBrown
bf4b490597 NFS: various changes relating to reporting IO errors.
1/ remove 'start' and 'end' args from nfs_file_fsync_commit().
   They aren't used.

2/ Make nfs_context_set_write_error() a "static inline" in internal.h
   so we can...

3/ Use nfs_context_set_write_error() instead of mapping_set_error()
   if nfs_pageio_add_request() fails before sending any request.
   NFS generally keeps errors in the open_context, not the mapping,
   so this is more consistent.

4/ If filemap_write_and_write_range() reports any error, still
   check ctx->error.  The value in ctx->error is likely to be
   more useful.  As part of this, NFS_CONTEXT_ERROR_WRITE is
   cleared slightly earlier, before nfs_file_fsync_commit() is called,
   rather than at the start of that function.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-11 22:28:56 -04:00
Chuck Lever
8224b2734a NFS: Add static NFS I/O tracepoints
Tools like tcpdump and rpcdebug can be very useful. But there are
plenty of environments where they are difficult or impossible to
use. For example, we've had customers report I/O failures during
workloads so heavy that collecting network traffic or enabling
RPC debugging are themselves onerous.

The kernel's static tracepoints are lightweight (less likely to
introduce timing changes) and efficient (the trace data is compact).
They also work in scenarios where capturing network traffic is not
possible due to lack of hardware support (some InfiniBand HCAs) or
where data or network privacy is a concern.

Introduce tracepoints that show when an NFS READ, WRITE, or COMMIT
is initiated, and when it completes. Record the arguments and
results of each operation, which are not shown by existing sunrpc
module's tracepoints.

For instance, the recorded offset and count can be used to match an
"initiate" event to a "done" event. If an NFS READ result returns
fewer bytes than requested or zero, seeing the EOF flag can be
probative. Seeing an NFS4ERR_BAD_STATEID result is also indication
of a particular class of problems. The timing information attached
to each event record can often be useful as well.

Usage example:

[root@manet tmp]# trace-cmd record -e nfs:*initiate* -e nfs:*done
/sys/kernel/debug/tracing/events/nfs/*initiate*/filter
/sys/kernel/debug/tracing/events/nfs/*done/filter
Hit Ctrl^C to stop recording
^CKernel buffer statistics:
  Note: "entries" are the entries left in the kernel ring buffer and are not
        recorded in the trace data. They should all be zero.

CPU: 0
entries: 0
overrun: 0
commit overrun: 0
bytes: 3680
oldest event ts:    78.367422
now ts:   100.124419
dropped events: 0
read events: 74

... and so on.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-11 22:20:38 -04:00
Trond Myklebust
70d2f7b1ea pNFS: Use the standard I/O stateid when calling LAYOUTGET
Instead of having a private method for copying the open/delegation stateid,
use the same call that is used for standard I/O through the MDS.

Note that this means we transmit the stateid with a zero seqid, avoiding
issues with NFS4ERR_OLD_STATEID.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-11 22:19:00 -04:00
Trond Myklebust
1bd5d6d08e NFS: Count the bytes of skipped subrequests in nfs_lock_and_join_requests()
If we skip a subrequest due to a zero refcount, we should still count
the byte range that it covered so that we accurately reconstruct the
original request size.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-09 16:43:09 -04:00
Linus Torvalds
ad9a19d003 More RDMA work and some op-structure constification from Chuck Lever,
and a small cleanup to our xdr encoding.
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Merge tag 'nfsd-4.14' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "More RDMA work and some op-structure constification from Chuck Lever,
  and a small cleanup to our xdr encoding"

* tag 'nfsd-4.14' of git://linux-nfs.org/~bfields/linux:
  svcrdma: Estimate Send Queue depth properly
  rdma core: Add rdma_rw_mr_payload()
  svcrdma: Limit RQ depth
  svcrdma: Populate tail iovec when receiving
  nfsd: Incoming xdr_bufs may have content in tail buffer
  svcrdma: Clean up svc_rdma_build_read_chunk()
  sunrpc: Const-ify struct sv_serv_ops
  nfsd: Const-ify NFSv4 encoding and decoding ops arrays
  sunrpc: Const-ify instances of struct svc_xprt_ops
  nfsd4: individual encoders no longer see error cases
  nfsd4: skip encoder in trivial error cases
  nfsd4: define ->op_release for compound ops
  nfsd4: opdesc will be useful outside nfs4proc.c
  nfsd4: move some nfsd4 op definitions to xdr4.h
2017-09-09 13:31:49 -07:00
Trond Myklebust
8b77484f2b NFS: Don't hold the group lock when calling nfs_release_request()
That can deadlock if this is the last reference since
nfs_page_group_destroy() calls nfs_page_group_sync_on_bit().
Note that even if the page was removed from the subpage list,
the req->wb_head could still be pointing to the old head.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-09 15:36:40 -04:00
Trond Myklebust
5d2a9d9dac NFS: Remove pnfs_generic_transfer_commit_list()
It's pretty much a duplicate of nfs_scan_commit_list() that also
clears the PG_COMMIT_TO_DS flag.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-09 12:51:40 -04:00
Trond Myklebust
137da553db NFS: nfs_lock_and_join_requests and nfs_scan_commit_list can deadlock
Since the commit list is not ordered, it is possible for nfs_scan_commit_list
to hold a request that nfs_lock_and_join_requests() is waiting for, while
at the same time trying to grab a request that nfs_lock_and_join_requests
already holds.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-09 12:28:01 -04:00
Trond Myklebust
196639ebbe NFS: Fix 2 use after free issues in the I/O code
The writeback code wants to send a commit after processing the pages,
which is why we want to delay releasing the struct path until after
that's done.

Also, the layout code expects that we do not free the inode before
we've put the layout segments in pnfs_writehdr_free() and
pnfs_readhdr_free()

Fixes: 919e3bd9a8 ("NFS: Ensure we commit after writeback is complete")
Fixes: 4714fb51fd ("nfs: remove pgio_header refcount, related cleanup")
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-08 22:07:52 -04:00
Linus Torvalds
a0725ab0c7 Merge branch 'for-4.14/block' of git://git.kernel.dk/linux-block
Pull block layer updates from Jens Axboe:
 "This is the first pull request for 4.14, containing most of the code
  changes. It's a quiet series this round, which I think we needed after
  the churn of the last few series. This contains:

   - Fix for a registration race in loop, from Anton Volkov.

   - Overflow complaint fix from Arnd for DAC960.

   - Series of drbd changes from the usual suspects.

   - Conversion of the stec/skd driver to blk-mq. From Bart.

   - A few BFQ improvements/fixes from Paolo.

   - CFQ improvement from Ritesh, allowing idling for group idle.

   - A few fixes found by Dan's smatch, courtesy of Dan.

   - A warning fixup for a race between changing the IO scheduler and
     device remova. From David Jeffery.

   - A few nbd fixes from Josef.

   - Support for cgroup info in blktrace, from Shaohua.

   - Also from Shaohua, new features in the null_blk driver to allow it
     to actually hold data, among other things.

   - Various corner cases and error handling fixes from Weiping Zhang.

   - Improvements to the IO stats tracking for blk-mq from me. Can
     drastically improve performance for fast devices and/or big
     machines.

   - Series from Christoph removing bi_bdev as being needed for IO
     submission, in preparation for nvme multipathing code.

   - Series from Bart, including various cleanups and fixes for switch
     fall through case complaints"

* 'for-4.14/block' of git://git.kernel.dk/linux-block: (162 commits)
  kernfs: checking for IS_ERR() instead of NULL
  drbd: remove BIOSET_NEED_RESCUER flag from drbd_{md_,}io_bio_set
  drbd: Fix allyesconfig build, fix recent commit
  drbd: switch from kmalloc() to kmalloc_array()
  drbd: abort drbd_start_resync if there is no connection
  drbd: move global variables to drbd namespace and make some static
  drbd: rename "usermode_helper" to "drbd_usermode_helper"
  drbd: fix race between handshake and admin disconnect/down
  drbd: fix potential deadlock when trying to detach during handshake
  drbd: A single dot should be put into a sequence.
  drbd: fix rmmod cleanup, remove _all_ debugfs entries
  drbd: Use setup_timer() instead of init_timer() to simplify the code.
  drbd: fix potential get_ldev/put_ldev refcount imbalance during attach
  drbd: new disk-option disable-write-same
  drbd: Fix resource role for newly created resources in events2
  drbd: mark symbols static where possible
  drbd: Send P_NEG_ACK upon write error in protocol != C
  drbd: add explicit plugging when submitting batches
  drbd: change list_for_each_safe to while(list_first_entry_or_null)
  drbd: introduce drbd_recv_header_maybe_unplug
  ...
2017-09-07 11:59:42 -07:00
tarangg@amazon.com
e973b1a599 NFS: Sync the correct byte range during synchronous writes
Since commit 18290650b1 ("NFS: Move buffered I/O locking into
nfs_file_write()") nfs_file_write() has not flushed the correct byte
range during synchronous writes.  generic_write_sync() expects that
iocb->ki_pos points to the right edge of the range rather than the
left edge.

To replicate the problem, open a file with O_DSYNC, have the client
write at increasing offsets, and then print the successful offsets.
Block port 2049 partway through that sequence, and observe that the
client application indicates successful writes in advance of what the
server received.

Fixes: 18290650b1 ("NFS: Move buffered I/O locking into nfs_file_write()")
Signed-off-by: Jacob Strauss <jsstraus@amazon.com>
Signed-off-by: Tarang Gupta <tarangg@amazon.com>
Tested-by: Tarang Gupta <tarangg@amazon.com>
Cc: stable@vger.kernel.org # v4.8+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-07 11:07:13 -04:00
Jan Kara
26b433d0da fscache: remove unused ->now_uncached callback
Patch series "Ranged pagevec lookup", v2.

In this series I make pagevec_lookup() update the index (to be
consistent with pagevec_lookup_tag() and also as a preparation for
ranged lookups), provide ranged variant of pagevec_lookup() and use it
in places where it makes sense.  This not only removes some common code
but is also a measurable performance win for some use cases (see patch
4/10) where radix tree is sparse and searching & grabing of a page after
the end of the range has measurable overhead.

This patch (of 10):

The callback doesn't ever get called.  Remove it.

Link: http://lkml.kernel.org/r/20170726114704.7626-2-jack@suse.cz
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06 17:27:26 -07:00
NeilBrown
03c6f7d64a NFS: remove jiffies field from access cache
This field hasn't been used since commit 57b691819e ("NFS: Cache
access checks more aggressively").

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-06 12:32:37 -04:00
NeilBrown
779eafab06 NFS: flush data when locking a file to ensure cache coherence for mmap.
When a byte range lock (or flock) is taken out on an NFS file, the
validity of the cached data is checked and the inode is marked
NFS_INODE_INVALID_DATA.  However the cached data isn't flushed from
the page cache.

This is sufficient for future read() requests or mmap() requests as
they call nfs_revalidate_mapping() which performs the flush if
necessary.

However an existing mapping is not affected.  Accessing data through
that mapping will continue to return old data even though the inode is
marked NFS_INODE_INVALID_DATA.

This can easily be confirmed using the 'nfs' tool in
  git://github.com/okirch/twopence-nfs.git
and running

   nfs coherence FILENAME
on one client, and
   nfs coherence -r FILENAME
on another client.

It appears that prior to Linux 2.6.0 this worked correctly.

However commit:

http://git.kernel.org/cgit/linux/kernel/git/history/history.git/commit/?id=ca9268fe3ddd075714005adecd4afbd7f9ab87d0

removed the call to inode_invalidate_pages() from nfs_zap_caches().  I
haven't tested this code, but inspection suggests that prior to this
commit, file locking would invalidate all inode pages.

This patch adds a call to nfs_revalidate_mapping() after a
successful SETLK so that invalid data is flushed.  With this patch the
above test passes.  To minimize impact (and possibly avoid a GETATTR
call) this only happens if the mapping might be mapped into
userspace.

Cc: Olaf Kirch <okir@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-06 12:31:15 -04:00
NeilBrown
237f8306c3 NFS: don't expect errors from mempool_alloc().
Commit fbe77c30e9 ("NFS: move rw_mode to nfs_pageio_header")
reintroduced some pointless code that commit 518662e0fc ("NFS: fix
usage of mempools.") had recently removed.

Remove it again.

Cc: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-09-06 12:31:15 -04:00
Chuck Lever
afea5657c2 sunrpc: Const-ify struct sv_serv_ops
Close an attack vector by moving the arrays of per-server methods to
read-only memory.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-08-24 22:13:50 -04:00
Christoph Hellwig
74d46992e0 block: replace bi_bdev with a gendisk pointer and partitions index
This way we don't need a block_device structure to submit I/O.  The
block_device has different life time rules from the gendisk and
request_queue and is usually only available when the block device node
is open.  Other callers need to explicitly create one (e.g. the lightnvm
passthrough code, or the new nvme multipathing code).

For the actual I/O path all that we need is the gendisk, which exists
once per block device.  But given that the block layer also does
partition remapping we additionally need a partition index, which is
used for said remapping in generic_make_request.

Note that all the block drivers generally want request_queue or
sometimes the gendisk, so this removes a layer of indirection all
over the stack.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 12:49:55 -06:00
Trond Myklebust
7af7a5963c Merge branch 'bugfixes' 2017-08-20 13:04:12 -04:00
Chuck Lever
53a75f22e7 NFS: Fix NFSv2 security settings
For a while now any NFSv2 mount where sec= is specified uses
AUTH_NULL. If sec= is not specified, the mount uses AUTH_UNIX.
Commit e68fd7c807 ("mount: use sec= that was specified on the
command line") attempted to address a very similar problem with
NFSv3, and should have fixed this too, but it has a bug.

The MNTv1 MNT procedure does not return a list of security flavors,
so our client makes up a list containing just AUTH_NULL. This should
enable nfs_verify_authflavors() to assign the sec= specified flavor,
but instead, it incorrectly sets it to AUTH_NULL.

I expect this would also be a problem for any NFSv3 server whose
MNTv3 MNT procedure returned a security flavor list containing only
AUTH_NULL.

Fixes: e68fd7c807 ("mount: use sec= that was specified on ... ")
BugLink: https://bugzilla.linux-nfs.org/show_bug.cgi?id=310
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-20 12:43:34 -04:00
NeilBrown
b79e87e070 NFSv4.1: don't use machine credentials for CLOSE when using 'sec=sys'
An NFSv4.1 client might close a file after the user who opened it has
logged off.  In this case the user's credentials may no longer be
valid, if they are e.g. kerberos credentials that have expired.

NFSv4.1 has a mechanism to allow the client to use machine credentials
to close a file.  However due to a short-coming in the RFC, a CLOSE
with those credentials may not be possible if the file in question
isn't exported to the same security flavor - the required PUTFH must
be rejected when this is the case.

Specifically if a server and client support kerberos in general and
have used it to form a machine credential, but the file is only
exported to "sec=sys", a PUTFH with the machine credentials will fail,
so CLOSE is not possible.

As RPC_AUTH_UNIX (used by sec=sys) credentials can never expire, there
is no value in using the machine credential in place of them.
So in that case, just use the users credentials for CLOSE etc, as you would
in NFSv4.0

Signed-off-by: Neil Brown <neilb@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-20 12:43:17 -04:00
Trond Myklebust
3bde7afdab NFS: Remove unused parameter gfp_flags from nfs_pageio_init()
Now that the mirror allocation has been moved, the parameter can go.
Also remove the redundant symbol export.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-20 11:35:33 -04:00
Trond Myklebust
14abcb0bf5 NFSv4: Fix up mirror allocation
There are a number of callers of nfs_pageio_complete() that want to
continue using the nfs_pageio_descriptor without needing to call
nfs_pageio_init() again. Examples include nfs_pageio_resend() and
nfs_pageio_cond_complete().

The problem is that nfs_pageio_complete() also calls
nfs_pageio_cleanup_mirroring(), which frees up the array of mirrors.
This can lead to writeback errors, in the next call to
nfs_pageio_setup_mirroring().

Fix by simply moving the allocation of the mirrors to
nfs_pageio_setup_mirroring().

Link: https://bugzilla.kernel.org/show_bug.cgi?id=196709
Reported-by: JianhongYin <yin-jianhong@163.com>
Cc: stable@vger.kernel.org # 4.0+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-20 10:36:35 -04:00
Trond Myklebust
b7561e5186 Merge branch 'writeback' 2017-08-18 14:51:10 -04:00
Trond Myklebust
2ce209c42c NFS: Wait for requests that are locked on the commit list
If a request is on the commit list, but is locked, we will currently skip
it, which can lead to livelocking when the commit count doesn't reduce
to zero.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:48 -04:00
Trond Myklebust
8205b9ce03 NFSv4/pnfs: Replace pnfs_put_lseg_locked() with pnfs_put_lseg()
Now that we no longer hold the inode->i_lock when manipulating the
commit lists, it is safe to call pnfs_put_lseg() again.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:48 -04:00
Trond Myklebust
4b9bb25b36 NFS: Switch to using mapping->private_lock for page writeback lookups.
Switch from using the inode->i_lock for this to avoid contention with
other metadata manipulation.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:48 -04:00
Trond Myklebust
5cb953d4b1 NFS: Use an atomic_long_t to count the number of commits
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:48 -04:00
Trond Myklebust
a6b6d5b85a NFS: Use an atomic_long_t to count the number of requests
Rather than forcing us to take the inode->i_lock just in order to bump
the number.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust
e824f99ada NFSv4: Use a mutex to protect the per-inode commit lists
The commit lists can get very large, so using the inode->i_lock can
end up affecting general metadata performance.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust
b30d2f04c3 NFS: Refactor nfs_page_find_head_request()
Split out the 2 cases so that we can treat the locking differently.
The issue is that the locking in the pageswapcache cache is highly
linked to the commit list locking.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust
bd37d6fce1 NFSv4: Convert nfs_lock_and_join_requests() to use nfs_page_find_head_request()
Hide the locking from nfs_lock_and_join_requests() so that we can
separate out the requirements for swapcache pages.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust
7e8a30f8b4 NFS: Fix up nfs_page_group_covers_page()
Fix up the test in nfs_page_group_covers_page(). The simplest implementation
is to check that we have a set of intersecting or contiguous subrequests
that connect page offset 0 to nfs_page_length(req->wb_page).

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust
1344b7ea17 NFS: Remove unused parameter from nfs_page_group_lock()
nfs_page_group_lock() is now always called with the 'nonblock'
parameter set to 'false'.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust
dee83046e7 NFS: Remove unuse function nfs_page_group_lock_wait()
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust
902a4c0046 NFS: Remove nfs_page_group_clear_bits()
At this point, we only expect ever to potentially see PG_REMOVE and
PG_TEARDOWN being set on the subrequests.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust
5b2b5187fa NFS: Fix nfs_page_group_destroy() and nfs_lock_and_join_requests() race cases
Since nfs_page_group_destroy() does not take any locks on the requests
to be freed, we need to ensure that we don't inadvertently free the
request in nfs_destroy_unlinked_subrequests() while the last reference
is being released elsewhere.

Do this by:

1) Taking a reference to the request unless it is already being freed
2) Checking (under the page group lock) if PG_TEARDOWN is already set before
   freeing an unreferenced request in nfs_destroy_unlinked_subrequests()

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust
74a6d4b5ae NFS: Further optimise nfs_lock_and_join_requests()
When locking the entire group in order to remove subrequests,
the locks are always taken in order, and with the page group
lock being taken after the page head is locked. The intention
is that:

1) The lock on the group head guarantees that requests may not
   be removed from the group (although new entries could be appended
   if we're not holding the group lock).
2) It is safe to drop and retake the page group lock while iterating
   through the list, in particular when waiting for a subrequest lock.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust
b5bab9bf91 NFS: Reduce inode->i_lock contention in nfs_lock_and_join_requests()
We should no longer need the inode->i_lock, now that we've
straightened out the request locking. The locking schema is now:

1) Lock page head request
2) Lock the page group
3) Lock the subrequests one by one

Note that there is a subtle race with nfs_inode_remove_request() due
to the fact that the latter does not lock the page head, when removing
it from the struct page. Only the last subrequest is locked, hence
we need to re-check that the PagePrivate(page) is still set after
we've locked all the subrequests.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00
Trond Myklebust
7e6cca6caf NFS: Remove page group limit in nfs_flush_incompatible()
nfs_try_to_update_request() should be able to cope now.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2017-08-15 11:54:47 -04:00