Commit Graph

2947 Commits

Author SHA1 Message Date
Trond Myklebust
c4271c6e37 NFS: Kill fscache warnings when mounting without -ofsc
The fscache code will currently bleat a "non-unique superblock keys"
warning even if the user is mounting without the 'fsc' option.

There should be no reason to even initialise the superblock cache cookie
unless we're planning on using fscache for something, so ensure that we
check for the NFS_OPTION_FSCACHE flag before calling into the fscache
code.

Reported-by: Paweł Sikora <pawel.sikora@agmk.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: David Howells <dhowells@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-21 08:32:09 -08:00
David Howells
c129c29347 NFS: Provide stub nfs_fscache_wait_on_invalidate() for when CONFIG_NFS_FSCACHE=n
Provide a stub nfs_fscache_wait_on_invalidate() function for when
CONFIG_NFS_FSCACHE=n lest the following error appear:

  fs/nfs/inode.c: In function 'nfs_invalidate_mapping':
  fs/nfs/inode.c:887:2: error: implicit declaration of function 'nfs_fscache_wait_on_invalidate' [-Werror=implicit-function-declaration]
  cc1: some warnings being treated as errors

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reported-by: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-21 08:06:48 -08:00
David Howells
a4ff146881 NFS4: Open files for fscaching
nfs4_file_open() should open files for fscaching.

Signed-off-by: David Howells <dhowells@redhat.com>
2012-12-20 22:19:42 +00:00
David Howells
8c209ce721 NFS: nfs_migrate_page() does not wait for FS-Cache to finish with a page
nfs_migrate_page() does not wait for FS-Cache to finish with a page, probably
leading to the following bad-page-state:

 BUG: Bad page state in process python-bin  pfn:17d39b
 page:ffffea00053649e8 flags:004000000000100c count:0 mapcount:0 mapping:(null)
index:38686 (Tainted: G    B      ---------------- )
 Pid: 31053, comm: python-bin Tainted: G    B      ----------------
2.6.32-71.24.1.el6.x86_64 #1
 Call Trace:
 [<ffffffff8111bfe7>] bad_page+0x107/0x160
 [<ffffffff8111ee69>] free_hot_cold_page+0x1c9/0x220
 [<ffffffff8111ef19>] __pagevec_free+0x59/0xb0
 [<ffffffff8104b988>] ? flush_tlb_others_ipi+0x128/0x130
 [<ffffffff8112230c>] release_pages+0x21c/0x250
 [<ffffffff8115b92a>] ? remove_migration_pte+0x28a/0x2b0
 [<ffffffff8115f3f8>] ? mem_cgroup_get_reclaim_stat_from_page+0x18/0x70
 [<ffffffff81122687>] ____pagevec_lru_add+0x167/0x180
 [<ffffffff811226f8>] __lru_cache_add+0x58/0x70
 [<ffffffff81122731>] lru_cache_add_lru+0x21/0x40
 [<ffffffff81123f49>] putback_lru_page+0x69/0x100
 [<ffffffff8115c0bd>] migrate_pages+0x13d/0x5d0
 [<ffffffff81122687>] ? ____pagevec_lru_add+0x167/0x180
 [<ffffffff81152ab0>] ? compaction_alloc+0x0/0x370
 [<ffffffff8115255c>] compact_zone+0x4cc/0x600
 [<ffffffff8111cfac>] ? get_page_from_freelist+0x15c/0x820
 [<ffffffff810672f4>] ? check_preempt_wakeup+0x1c4/0x3c0
 [<ffffffff8115290e>] compact_zone_order+0x7e/0xb0
 [<ffffffff81152a49>] try_to_compact_pages+0x109/0x170
 [<ffffffff8111e94d>] __alloc_pages_nodemask+0x5ed/0x850
 [<ffffffff814c9136>] ? thread_return+0x4e/0x778
 [<ffffffff81150d43>] alloc_pages_vma+0x93/0x150
 [<ffffffff81167ea5>] do_huge_pmd_anonymous_page+0x135/0x340
 [<ffffffff814cb6f6>] ? rwsem_down_read_failed+0x26/0x30
 [<ffffffff81136755>] handle_mm_fault+0x245/0x2b0
 [<ffffffff814ce383>] do_page_fault+0x123/0x3a0
 [<ffffffff814cbdf5>] page_fault+0x25/0x30

nfs_migrate_page() calls nfs_fscache_release_page() which doesn't actually wait
- even if __GFP_WAIT is set.  The reason that doesn't wait is that
fscache_maybe_release_page() might deadlock the allocator as the work threads
writing to the cache may all end up sleeping on memory allocation.

However, I wonder if that is actually a problem.  There are a number of things
I can do to deal with this:

 (1) Make nfs_migrate_page() wait.

 (2) Make fscache_maybe_release_page() honour the __GFP_WAIT flag.

 (3) Set a timeout around the wait.

 (4) Make nfs_migrate_page() return an error if the page is still busy.

For the moment, I'll select (2) and (4).

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
2012-12-20 22:12:03 +00:00
David Howells
de242c0b8b NFS: Use FS-Cache invalidation
Use the new FS-Cache invalidation facility from NFS to deal with foreign
changes being detected on the server rather than attempting to retire the old
cookie and get a new one.

The problem with the old method was that NFS did not wait for all outstanding
storage and retrieval ops on the cache to complete.  There was no automatic
wait between the calls to ->readpages() and calls to invalidate_inode_pages2()
as the latter can only wait on locked pages that have been added to the
pagecache (which they haven't yet on entry to ->readpages()).

This was leading to oopses like the one below when an outstanding read got cut
off from its cookie by a premature release.

BUG: unable to handle kernel NULL pointer dereference at 00000000000000a8
IP: [<ffffffffa0075118>] __fscache_read_or_alloc_pages+0x1dd/0x315 [fscache]
PGD 15889067 PUD 15890067 PMD 0
Oops: 0000 [#1] SMP
CPU 0
Modules linked in: cachefiles nfs fscache auth_rpcgss nfs_acl lockd sunrpc

Pid: 4544, comm: tar Not tainted 3.1.0-rc4-fsdevel+ #1064                  /DG965RY
RIP: 0010:[<ffffffffa0075118>]  [<ffffffffa0075118>] __fscache_read_or_alloc_pages+0x1dd/0x315 [fscache]
RSP: 0018:ffff8800158799e8  EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8800070d41e0 RCX: ffff8800083dc1b0
RDX: 0000000000000000 RSI: ffff880015879960 RDI: ffff88003e627b90
RBP: ffff880015879a28 R08: 0000000000000002 R09: 0000000000000002
R10: 0000000000000001 R11: ffff880015879950 R12: ffff880015879aa4
R13: 0000000000000000 R14: ffff8800083dc158 R15: ffff880015879be8
FS:  00007f671e9d87c0(0000) GS:ffff88003bc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 00000000000000a8 CR3: 000000001587f000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process tar (pid: 4544, threadinfo ffff880015878000, task ffff880015875040)
Stack:
 ffffffffa00b1759 ffff8800070dc158 ffff8800000213da ffff88002a286508
 ffff880015879aa4 ffff880015879be8 0000000000000001 ffff88002a2866e8
 ffff880015879a88 ffffffffa00b20be 00000000000200da ffff880015875040
Call Trace:
 [<ffffffffa00b1759>] ? nfs_fscache_wait_bit+0xd/0xd [nfs]
 [<ffffffffa00b20be>] __nfs_readpages_from_fscache+0x7e/0x13f [nfs]
 [<ffffffff81095fe7>] ? __alloc_pages_nodemask+0x156/0x662
 [<ffffffffa0098763>] nfs_readpages+0xee/0x187 [nfs]
 [<ffffffff81098a5e>] __do_page_cache_readahead+0x1be/0x267
 [<ffffffff81098942>] ? __do_page_cache_readahead+0xa2/0x267
 [<ffffffff81098d7b>] ra_submit+0x1c/0x20
 [<ffffffff8109900a>] ondemand_readahead+0x28b/0x29a
 [<ffffffff810990ce>] page_cache_sync_readahead+0x38/0x3a
 [<ffffffff81091d8a>] generic_file_aio_read+0x2ab/0x67e
 [<ffffffffa008cfbe>] nfs_file_read+0xa4/0xc9 [nfs]
 [<ffffffff810c22c4>] do_sync_read+0xba/0xfa
 [<ffffffff810a62c9>] ? might_fault+0x4e/0x9e
 [<ffffffff81177a47>] ? security_file_permission+0x7b/0x84
 [<ffffffff810c25dd>] ? rw_verify_area+0xab/0xc8
 [<ffffffff810c29a4>] vfs_read+0xaa/0x13a
 [<ffffffff810c2a79>] sys_read+0x45/0x6c
 [<ffffffff813ac37b>] system_call_fastpath+0x16/0x1b

Reported-by: Mark Moseley <moseleymark@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2012-12-20 22:06:33 +00:00
Linus Torvalds
2d4dce0070 NFS client updates for Linux 3.8
Features include:
 
 - Full audit of BUG_ON asserts in the NFS, SUNRPC and lockd client code
   Remove altogether where possible, and replace with WARN_ON_ONCE and
   appropriate error returns where not.
 - NFSv4.1 client adds session dynamic slot table management. There is
   matching server side code that has been submitted to Bruce for
   consideration. Together, this code allows the server to dynamically
   manage the amount of memory it allocates to the duplicate request
   cache for each client. It will constantly resize those caches to
   reserve more memory for clients that are hot while shrinking caches
   for those that are quiescent.
 
 In addition, there are assorted bugfixes for the generic NFS write code,
 fixes to deal with the drop_nlink() warnings, and yet another fix for
 NFSv4 getacl.
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Merge tag 'nfs-for-3.8-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

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

   - Full audit of BUG_ON asserts in the NFS, SUNRPC and lockd client
     code.  Remove altogether where possible, and replace with
     WARN_ON_ONCE and appropriate error returns where not.
   - NFSv4.1 client adds session dynamic slot table management.  There
     is matching server side code that has been submitted to Bruce for
     consideration.

     Together, this code allows the server to dynamically manage the
     amount of memory it allocates to the duplicate request cache for
     each client.  It will constantly resize those caches to reserve
     more memory for clients that are hot while shrinking caches for
     those that are quiescent.

  In addition, there are assorted bugfixes for the generic NFS write
  code, fixes to deal with the drop_nlink() warnings, and yet another
  fix for NFSv4 getacl."

* tag 'nfs-for-3.8-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (106 commits)
  SUNRPC: continue run over clients list on PipeFS event instead of break
  NFS: Don't use SetPageError in the NFS writeback code
  SUNRPC: variable 'svsk' is unused in function bc_send_request
  SUNRPC: Handle ECONNREFUSED in xs_local_setup_socket
  NFSv4.1: Deal effectively with interrupted RPC calls.
  NFSv4.1: Move the RPC timestamp out of the slot.
  NFSv4.1: Try to deal with NFS4ERR_SEQ_MISORDERED.
  NFS: nfs_lookup_revalidate should not trust an inode with i_nlink == 0
  NFS: Fix calls to drop_nlink()
  NFS: Ensure that we always drop inodes that have been marked as stale
  nfs: Remove unused list nfs4_clientid_list
  nfs: Remove duplicate function declaration in internal.h
  NFS: avoid NULL dereference in nfs_destroy_server
  SUNRPC handle EKEYEXPIRED in call_refreshresult
  SUNRPC set gss gc_expiry to full lifetime
  nfs: fix page dirtying in NFS DIO read codepath
  nfs: don't zero out the rest of the page if we hit the EOF on a DIO READ
  NFSv4.1: Be conservative about the client highest slotid
  NFSv4.1: Handle NFS4ERR_BADSLOT errors correctly
  nfs: don't extend writes to cover entire page if pagecache is invalid
  ...
2012-12-18 09:36:34 -08:00
Andrew Morton
965c8e59cf lseek: the "whence" argument is called "whence"
But the kernel decided to call it "origin" instead.  Fix most of the
sites.

Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17 17:15:12 -08:00
Linus Torvalds
2a74dbb9a8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull security subsystem updates from James Morris:
 "A quiet cycle for the security subsystem with just a few maintenance
  updates."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  Smack: create a sysfs mount point for smackfs
  Smack: use select not depends in Kconfig
  Yama: remove locking from delete path
  Yama: add RCU to drop read locking
  drivers/char/tpm: remove tasklet and cleanup
  KEYS: Use keyring_alloc() to create special keyrings
  KEYS: Reduce initial permissions on keys
  KEYS: Make the session and process keyrings per-thread
  seccomp: Make syscall skipping and nr changes more consistent
  key: Fix resource leak
  keys: Fix unreachable code
  KEYS: Add payload preparsing opportunity prior to key instantiate or update
2012-12-16 15:40:50 -08:00
Trond Myklebust
ada8e20d04 NFS: Don't use SetPageError in the NFS writeback code
The writeback code is already capable of passing errors back to user space
by means of the open_context->error. In the case of ENOSPC, Neil Brown
is reporting seeing 2 errors being returned.

Neil writes:

"e.g. if /mnt2/ if an nfs mounted filesystem that has no space then

strace dd if=/dev/zero conv=fsync >> /mnt2/afile count=1

reported Input/output error and the relevant parts of the strace output are:

write(1, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 512) = 512
fsync(1)                                = -1 EIO (Input/output error)
close(1)                                = -1 ENOSPC (No space left on device)"

Neil then shows that the duplication of error messages appears to be due to
the use of the PageError() mechanism, which causes filemap_fdatawait_range
to return the extra EIO. The regression was introduced by
commit 7b281ee026 (NFS: fsync() must exit
with an error if page writeback failed).

Fix this by removing the call to SetPageError(), and just relying on
open_context->error reporting the ENOSPC back to fsync().

Reported-by: Neil Brown <neilb@suse.de>
Tested-by: Neil Brown <neilb@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org [3.6+]
2012-12-15 17:12:14 -05:00
Trond Myklebust
ac20d163fc NFSv4.1: Deal effectively with interrupted RPC calls.
If an RPC call is interrupted, assume that the server hasn't processed
the RPC call so that the next time we use the slot, we know that if we
get a NFS4ERR_SEQ_MISORDERED or NFS4ERR_SEQ_FALSE_RETRY, we just have
to bump the sequence number.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-15 15:39:59 -05:00
Trond Myklebust
8e63b6a8ad NFSv4.1: Move the RPC timestamp out of the slot.
Shave a few bytes off the slot table size by moving the RPC timestamp
into the sequence results.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-15 15:21:52 -05:00
Trond Myklebust
e879444084 NFSv4.1: Try to deal with NFS4ERR_SEQ_MISORDERED.
If the server returns NFS4ERR_SEQ_MISORDERED, it could be a sign
that the slot was retired at some point. Retry the attempt after
reinitialising the slot sequence number to 1.

Also add a handler for NFS4ERR_SEQ_FALSE_RETRY. Just bump the slot
sequence number and retry...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-15 14:49:09 -05:00
Trond Myklebust
65a0c14954 NFS: nfs_lookup_revalidate should not trust an inode with i_nlink == 0
If the inode has no links, then we should force a new lookup.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-14 17:51:40 -05:00
Trond Myklebust
1f018458b3 NFS: Fix calls to drop_nlink()
It is almost always wrong for NFS to call drop_nlink() after removing a
file. What we really want is to mark the inode's attributes for
revalidation, and we want to ensure that the VFS drops it if we're
reasonably sure that this is the final unlink().
Do the former using the usual cache validity flags, and the latter
by testing if inode->i_nlink == 1, and clearing it in that case.

This also fixes the following warning reported by Neil Brown and
Jeff Layton (among others).

[634155.004438] WARNING:
at /home/abuild/rpmbuild/BUILD/kernel-desktop-3.5.0/lin [634155.004442]
Hardware name: Latitude E6510 [634155.004577]  crc_itu_t crc32c_intel
snd_hwdep snd_pcm snd_timer snd soundcor [634155.004609] Pid: 13402, comm:
bash Tainted: G        W    3.5.0-36-desktop # [634155.004611] Call Trace:
[634155.004630]  [<ffffffff8100444a>] dump_trace+0xaa/0x2b0
[634155.004641]  [<ffffffff815a23dc>] dump_stack+0x69/0x6f
[634155.004653]  [<ffffffff81041a0b>] warn_slowpath_common+0x7b/0xc0
[634155.004662]  [<ffffffff811832e4>] drop_nlink+0x34/0x40
[634155.004687]  [<ffffffffa05bb6c3>] nfs_dentry_iput+0x33/0x70 [nfs]
[634155.004714]  [<ffffffff8118049e>] dput+0x12e/0x230
[634155.004726]  [<ffffffff8116b230>] __fput+0x170/0x230
[634155.004735]  [<ffffffff81167c0f>] filp_close+0x5f/0x90
[634155.004743]  [<ffffffff81167cd7>] sys_close+0x97/0x100
[634155.004754]  [<ffffffff815c3b39>] system_call_fastpath+0x16/0x1b
[634155.004767]  [<00007f2a73a0d110>] 0x7f2a73a0d10f

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org [3.3+]
2012-12-14 17:45:11 -05:00
Trond Myklebust
eed9935745 NFS: Ensure that we always drop inodes that have been marked as stale
There is no need to cache stale inodes.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-14 14:36:36 -05:00
Yanchuan Nian
48d7a57693 nfs: Remove unused list nfs4_clientid_list
This list was designed to store struct nfs4_client in the client side.
But nfs4_client was obsolete and has been removed from the source code.
So remove the unused list.

Signed-off-by: Yanchuan Nian <ycnian@gmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-13 10:40:09 -05:00
Yanchuan Nian
aaea7d2f78 nfs: Remove duplicate function declaration in internal.h
Remove duplicate function declaration in internal.h

Signed-off-by: Yanchuan Nian <ycnian@gmail.com>
[Trond: Added nfs_pageio_init_read, which suffered from the same problem]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-13 10:38:54 -05:00
NeilBrown
f259613a1e NFS: avoid NULL dereference in nfs_destroy_server
In rare circumstances, nfs_clone_server() of a v2 or v3 server can get
an error between setting server->destory (to nfs_destroy_server), and
calling nfs_start_lockd (which will set server->nlm_host).

If this happens, nfs_clone_server will call nfs_free_server which
will call nfs_destroy_server and thence nlmclnt_done(NULL).  This
causes the NULL to be dereferenced.

So add a guard to only call nlmclnt_done() if ->nlm_host is not NULL.

The other guards there are irrelevant as nlm_host can only be non-NULL
if one of these flags are set - so remove those tests.  (Thanks to Trond
for this suggestion).

This is suitable for any stable kernel since 2.6.25.

Cc: stable@vger.kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-12 23:55:56 -05:00
Andy Adamson
eb96d5c97b SUNRPC handle EKEYEXPIRED in call_refreshresult
Currently, when an RPCSEC_GSS context has expired or is non-existent
and the users (Kerberos) credentials have also expired or are non-existent,
the client receives the -EKEYEXPIRED error and tries to refresh the context
forever.  If an application is performing I/O, or other work against the share,
the application hangs, and the user is not prompted to refresh/establish their
credentials. This can result in a denial of service for other users.

Users are expected to manage their Kerberos credential lifetimes to mitigate
this issue.

Move the -EKEYEXPIRED handling into the RPC layer. Try tk_cred_retry number
of times to refresh the gss_context, and then return -EACCES to the application.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-12 15:36:02 -05:00
Jeff Layton
be7e985804 nfs: fix page dirtying in NFS DIO read codepath
The NFS DIO code will dirty pages that catch read responses in order to
handle the case where someone is doing DIO reads into an mmapped buffer.
The existing code doesn't really do the right thing though since it
doesn't take into account the case where we might be attempting to read
past the EOF.

Fix the logic in that code to only dirty pages that ended up receiving
data from the read. Note too that it really doesn't matter if
NFS_IOHDR_ERROR is set or not. All that matters is if the page was
altered by the read.

Cc: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-12 12:56:19 -05:00
Jeff Layton
67fad106a2 nfs: don't zero out the rest of the page if we hit the EOF on a DIO READ
Eryu provided a test program that would segfault when attempting to read
past the EOF on file that was opened O_DIRECT. The buffer given to the
read() call was on the stack, and when he attempted to read past it it
would scribble over the rest of the stack page.

If we hit the end of the file on a DIO READ request, then we don't want
to zero out the rest of the buffer. These aren't pagecache pages after
all, and there's no guarantee that the buffers that were passed in
represent entire pages.

Cc: <stable@vger.kernel.org> # v3.5+
Cc: Fred Isaman <iisaman@netapp.com>
Reported-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-12 12:56:09 -05:00
Trond Myklebust
b0ef9647a0 NFSv4.1: Be conservative about the client highest slotid
If the server sends us a target that looks like an outlier, but
is lower than the existing target, then respect it anyway.
However defer actually updating the generation counter until
we get a target that doesn't look like an outlier.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-11 12:29:10 -05:00
Trond Myklebust
8556307374 NFSv4.1: Handle NFS4ERR_BADSLOT errors correctly
Most (all) NFS4ERR_BADSLOT errors are due to the client failing to
respect the server's sr_highest_slotid limit. This mainly happens
due to reordered RPC requests.
The way to handle it is simply to drop the slot that we're using,
and retry using the new highest_slotid limits.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-11 10:31:12 -05:00
Trond Myklebust
7ce0171d4f Merge branch 'bugfixes' into nfs-for-next 2012-12-11 09:16:26 -05:00
Jeff Layton
81d9bce530 nfs: don't extend writes to cover entire page if pagecache is invalid
Jian reported that the following sequence would leave "testfile" with
corrupt data:

    # mount localhost:/export /mnt/nfs/ -o vers=3
    # echo abc > /mnt/nfs/testfile; echo def >> /export/testfile; echo ghi >> /mnt/nfs/testfile
    # cat -v /export/testfile
    abc
    ^@^@^@^@ghi

While there's no locking involved here, the operations are serialized,
so CTO should prevent corruption.

The first write to the file is fine and writes 4 bytes. The file is then
extended on the server. When it's reopened a GETATTR is issued and the
size change is noticed. This causes NFS_INO_INVALID_DATA to be set on
the file. Because the file is opened for write only,
nfs_want_read_modify_write() returns 0 to nfs_write_begin().
nfs_updatepage then calls nfs_write_pageuptodate() to see if it should
extend the nfs_page to cover the whole page. NFS_INO_INVALID_DATA is
still set on the file at that point, but that flag is ignored and
nfs_pageuptodate erroneously extends the write to cover the whole page,
with the write done on the server side filled in with zeroes.

This patch just has that function check for NFS_INO_INVALID_DATA in
addition to NFS_INO_REVAL_PAGECACHE. This fixes the bug, but looking
over the code, I wonder if we might have a similar bug in
nfs_revalidate_size(). The difference between those two flags is very
subtle, so it seems like we ought to be checking for
NFS_INO_INVALID_DATA in most of the places that we look for
NFS_INO_REVAL_PAGECACHE.

I believe this is regression introduced by commit 8d197a568. The code
did check for NFS_INO_INVALID_DATA prior to that patch.

Original bug report is here:

    https://bugzilla.redhat.com/show_bug.cgi?id=885743

Cc: <stable@vger.kernel.org> # 3.5+
Reported-by: Jian Li <jiali@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-11 09:14:51 -05:00
Sven Wegener
7d3e91a89b NFSv4: Check for buffer length in __nfs4_get_acl_uncached
Commit 1f1ea6c "NFSv4: Fix buffer overflow checking in
__nfs4_get_acl_uncached" accidently dropped the checking for too small
result buffer length.

If someone uses getxattr on "system.nfs4_acl" on an NFSv4 mount
supporting ACLs, the ACL has not been cached and the buffer suplied is
too short, we still copy the complete ACL, resulting in kernel and user
space memory corruption.

Signed-off-by: Sven Wegener <sven.wegener@stealer.net>
Cc: stable@kernel.org
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-11 09:14:50 -05:00
Trond Myklebust
1fa8064429 NFSv4.1: Try to eliminate outliers when updating target_highest_slotid
Look for sudden changes in the first and second derivatives in order
to eliminate outlier changes to target_highest_slotid (which are
due to out-of-order RPC replies).

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:53 +01:00
Trond Myklebust
b75ad4cda5 NFSv4.1: Ensure smooth handover of slots from one task to the next waiting
Currently, we see a lot of bouncing for the value of highest_used_slotid
due to the fact that slots are getting freed, instead of getting instantly
transmitted to the next waiting task.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:52 +01:00
Trond Myklebust
1e1093c7fd NFSv4.1: Don't mess with task priorities in nfs41_setup_sequence
We want to preserve the rpc_task priority for things like writebacks,
that may have differing levels of urgency.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:51 +01:00
Bryan Schumaker
104287cd4e NFS: Remove _nfs_call_sync_session
All it does is pass its arguments through to another function.  Let's
cut out the middleman...

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:51 +01:00
Trond Myklebust
8fe72bac8d NFSv4: Clean up handling of privileged operations
Privileged rpc calls are those that are run by the state recovery thread,
in cases where we're trying to recover the system after a server reboot
or a network partition. In those cases, we want to fence off all other
rpc calls (see nfs4_begin_drain_session()) so that they don't end up
using stateids or clientids that are in the process of being recovered.

Prior to this patch, we had to set up special callback functions in
order to declare an rpc call as being privileged.
By adding a new field to the sequence arguments, this patch simplifies
things considerably, and allows us to declare the rpc call as privileged
before it is run.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:50 +01:00
Trond Myklebust
275e7e20aa NFSv4.1: Remove the 'FIFO' behaviour for nfs41_setup_sequence
It is more important to preserve the task priority behaviour, which ensures
that things like reclaim writes take precedence over background and kupdate
writes.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:50 +01:00
Trond Myklebust
7b939a3f44 NFSv4.1: Clean up nfs41_setup_sequence
Move all the sleep-and-exit cases into a single section of code.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:49 +01:00
Trond Myklebust
fd0c09537a NFSv4: Simplify the NFSv4/v4.1 synchronous call switch
We shouldn't need to pass the 'cache_reply' parameter if we
initialise the sequence_args/sequence_res in the caller.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:49 +01:00
Trond Myklebust
d9afbd1b08 NFSv4.1: Simplify the sequence setup
Nobody calls nfs4_setup_sequence or nfs41_setup_sequence without
also calling rpc_call_start() on success. This commit therefore
folds the rpc_call_start call into nfs41_setup_sequence().

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:48 +01:00
Trond Myklebust
6ba7db3420 NFSv4.1: Use nfs41_setup_sequence where appropriate
There is no point in using nfs4_setup_sequence or nfs4_sequence_done
in pure NFSv4.1 functions. We already know that those have sessions...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:48 +01:00
Trond Myklebust
c10e449827 NFSv4.1: Ping server when our session table limits are too high
If the server requests a lower target_highest_slotid, then ensure
that we ping it with at least one RPC call containing an
appropriate SEQUENCE op. This ensures that the server won't need to
send a recall callback in order to shrink the slot table.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:47 +01:00
Trond Myklebust
0ca3f4825a NFSv4.1: Set the maximum slot table size to 1024 slots
This means that we end up statically allocating 128 bytes for the
bitmap on each slot table.
For a server that supports 1MB write and read I/O sizes this means
that we can completely fill the maximum 1GB TCP send/receive
windows.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:47 +01:00
Trond Myklebust
76e697ba7e NFSv4.1: Move slot table and session struct definitions to nfs4session.h
Clean up. Gather NFSv4.1 slot definitions in fs/nfs/nfs4session.h.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:46 +01:00
Trond Myklebust
73e39aaa83 NFSv4.1: Cleanup move session slot management to fs/nfs/nfs4session.c
NFSv4.1 session management is getting complex enough to deserve
a separate file.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:45 +01:00
Trond Myklebust
3302127967 NFSv4: Move nfs4_wait_clnt_recover and nfs4_client_recover_expired_lease
nfs4_wait_clnt_recover and nfs4_client_recover_expired_lease are both
generic state related functions. As such, they belong in nfs4state.c,
and not nfs4proc.c

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:45 +01:00
Trond Myklebust
5d63360dd8 NFSv4.1: Clean up session draining
Coalesce nfs4_check_drain_bc_complete and nfs4_check_drain_fc_complete
into a single function that can be called when the slot table is known
to be empty, then change nfs4_callback_free_slot() and nfs4_free_slot()
to use it.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:44 +01:00
Trond Myklebust
69d206b5b3 NFSv4.1: If slot allocation fails due to OOM, retry more quickly
If the NFSv4.1 session slot allocation fails due to an ENOMEM condition,
then set the task->tk_timeout to 1/4 second to ensure that we do retry
the slot allocation more quickly.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:44 +01:00
Trond Myklebust
ac0748359a NFSv4.1: CB_RECALL_SLOT must schedule a sequence op after updating targets
RFC5661 requires us to make sure that the server knows we've updated
our slot table size by sending at least one SEQUENCE op containing the
new 'highest_slotid' value.
We can do so using the 'CHECK_LEASE' functionality of the state
manager.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:43 +01:00
Trond Myklebust
afa296103e NFSv4.1: Remove the state manager code to resize the slot table
The state manager no longer needs any special machinery to stop the
session flow and resize the slot table. It is all done on the fly by
the SEQUENCE op code now.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:43 +01:00
Trond Myklebust
87dda67e73 NFSv4.1: Allow SEQUENCE to resize the slot table on the fly
Instead of an array of slots, use a singly linked list of slots that
can be dynamically appended to or shrunk.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:42 +01:00
Trond Myklebust
97e548a93d NFSv4.1: Support dynamic resizing of the session slot table
Allow the server to control the size of the session slot table
by adjusting the value of sr_target_max_slots in the reply to the
SEQUENCE operation.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:42 +01:00
Trond Myklebust
1b285ff16a NFSv4.1: Allow the server to recall all but one slot
If the server wants to leave us with only one slot, or it wants
to "shrink" our slot table to something larger than we have now,
then so be it.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:42 +01:00
Trond Myklebust
d5fb4ce33e NFSv4.1: Don't confuse target_highest_slotid and max_slots in cb_recall_slot
Don't confuse the table size and the target_highest_slotid...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:41 +01:00
Trond Myklebust
ce008c4bb9 NFSv4.1: Fix nfs4_callback_recallslot to work with dynamic slot allocation
Ensure that the NFSv4.1 CB_RECALL_SLOT callback updates the slot table
target max slotid safely.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-12-06 00:30:37 +01:00