If the server does not return a valid set of attributes that we can
use to either create a file or refresh the inode, then there is no
value in calling nfs_prime_dcache().
However if we're just refreshing the inode using the attributes that
the server returned, then it shouldn't matter whether or not we have
a filehandle, as long as we check the fsid+fileid combination.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If we're traversing a directory which contains a submounted filesystem,
or one that has a referral, the NFS server that is processing the READDIR
request will often return information for the underlying (mounted-on)
directory. It may, or may not, also return filehandle information.
If this happens, and the lookup in nfs_prime_dcache() returns the
dentry for the submounted directory, the filehandle comparison will
fail, and we call d_invalidate(). Post-commit 8ed936b567
("vfs: Lazily remove mounts on unlinked files and directories."), this
means the entire subtree is unmounted.
The following minimal patch addresses this problem by punting on
the invalidation if there is a submount.
Kudos to Neil Brown <neilb@suse.de> for having tracked down this
issue (see link).
Reported-by: Nix <nix@esperi.org.uk>
Link: http://lkml.kernel.org/r/87iofju9ht.fsf@spindle.srvr.nix
Cc: stable@vger.kernel.org # 3.18+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
If the OPEN rpc call to the server fails with an ENOENT call, nfs_atomic_open
will create a negative dentry for that file, however it currently fails
to call nfs_set_verifier(), thus causing the dentry to be immediately
revalidated on the next call to nfs_lookup_revalidate() instead of following
the usual lookup caching rules.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Now that d_invalidate can no longer fail, stop returning a useless
return code. For the few callers that checked the return code update
remove the handling of d_invalidate failure.
Reviewed-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Now that check_submounts_and_drop can not fail and is called from
d_invalidate there is no longer a need to call check_submounts_and_drom
from filesystem d_revalidate methods so remove it.
Reviewed-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
1/ rcu_dereference isn't correct: that field isn't
RCU protected. It could potentially change at any time
so ACCESS_ONCE might be justified.
changes to ->d_parent are protected by ->d_seq. However
that isn't always checked after ->d_revalidate is called,
so it is safest to keep the double-check that ->d_parent
hasn't changed at the end of these functions.
2/ in nfs4_lookup_revalidate, "->d_parent" was forgotten.
So 'parent' was not the parent of 'dentry'.
This fails safe is the context is that dentry->d_inode is
NULL, and the result of parent->d_inode being NULL is
that ECHILD is returned, which is always safe.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
The access cache is used during RCU-walk path lookups, so it is best
to avoid locking if possible as taking a lock kills concurrency.
The rbtree is not rcu-safe and cannot easily be made so.
Instead we simply check the last (i.e. most recent) entry on the LRU
list. If this doesn't match, then we return -ECHILD and retry in
lock/refcount mode.
This requires freeing the nfs_access_entry struct with rcu, and
requires using rcu access primatives when adding entries to the lru, and
when examining the last entry.
Calling put_rpccred before kfree_rcu looks a bit odd, but as
put_rpccred already provides rcu protection, we know that the cred will
not actually be freed until the next grace period, so any concurrent
access will be safe.
This patch provides about 5% performance improvement on a stat-heavy
synthetic work load with 4 threads on a 2-core CPU.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
It fails with -ECHILD rather than make an RPC call.
This allows nfs_lookup_revalidate to call it in RCU-walk mode.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This requires nfs_check_verifier to take an rcu_walk flag, and requires
an rcu version of nfs_revalidate_inode which returns -ECHILD rather
than making an RPC call.
With this, nfs_lookup_revalidate can call nfs_neg_need_reval in
RCU-walk mode.
We can also move the LOOKUP_RCU check past the nfs_check_verifier()
call in nfs_lookup_revalidate.
If RCU_WALK prevents nfs_check_verifier or nfs_neg_need_reval from
doing a full check, they return a status indicating that a revalidation
is required. As this revalidation will not be possible in RCU_WALK
mode, -ECHILD will ultimately be returned, which is the desired result.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
nfs_permission makes two calls which are not always safe in RCU_WALK,
rpc_lookup_cred and nfs_do_access.
The second can easily be made rcu-safe by aborting with -ECHILD before
making the RPC call.
The former can be made rcu-safe by calling rpc_lookup_cred_nonblock()
instead.
As this will almost always succeed, we use it even when RCU_WALK
isn't being used as it still saves some spinlocks in a common case.
We only fall back to rpc_lookup_cred() if rpc_lookup_cred_nonblock()
fails and MAY_NOT_BLOCK isn't set.
This optimisation (always trying rpc_lookup_cred_nonblock()) is
particularly important when a security module is active.
In that case inode_permission() may return -ECHILD from
security_inode_permission() even though ->permission() succeeded in
RCU_WALK mode.
This leads to may_lookup() retrying inode_permission after performing
unlazy_walk(). The spinlock that rpc_lookup_cred() takes is often
more expensive than anything security_inode_permission() does, so that
spinlock becomes the main bottleneck.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
nfs_lookup_revalidate, nfs4_lookup_revalidate, and nfs_permission
all need to understand and handle RCU-walk for NFS to gain the
benefits of RCU-walk for cached information.
Currently these functions all immediately return -ECHILD
if the relevant flag (LOOKUP_RCU or MAY_NOT_BLOCK) is set.
This patch pushes those tests later in the code so that we only abort
immediately before we enter rcu-unsafe code. As subsequent patches
make that rcu-unsafe code rcu-safe, several of these new tests will
disappear.
With this patch there are several paths through the code which will no
longer return -ECHILD during an RCU-walk. However these are mostly
error paths or other uninteresting cases.
A noteworthy change in nfs_lookup_revalidate is that we don't take
(or put) the reference to ->d_parent when LOOKUP_RCU is set.
Rather we rcu_dereference ->d_parent, and check that ->d_inode
is not NULL. We also check that ->d_parent hasn't changed after
all the tests.
In nfs4_lookup_revalidate we simply avoid testing LOOKUP_RCU on the
path that only calls nfs_lookup_revalidate() as that function
already performs the required test.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
nfs4_lookup_revalidate only uses 'parent' to get 'dir', and only
uses 'dir' if 'inode == NULL'.
So we don't need to find out what 'parent' or 'dir' is until we
know that 'inode' is NULL.
By moving 'dget_parent' inside the 'if', we can reduce the number of
call sites for 'dput(parent)'.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This may be used to limit the number of cached credentials building up
inside the access cache.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Highlights include:
- Stable fix for a use after free issue in the NFSv4.1 open code
- Fix the SUNRPC bi-directional RPC code to account for TCP segmentation
- Optimise usage of readdirplus when confronted with 'ls -l' situations
- Soft mount bugfixes
- NFS over RDMA bugfixes
- NFSv4 close locking fixes
- Various NFSv4.x client state management optimisations
- Rename/unlink code cleanups
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Merge tag 'nfs-for-3.15-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
- Stable fix for a use after free issue in the NFSv4.1 open code
- Fix the SUNRPC bi-directional RPC code to account for TCP segmentation
- Optimise usage of readdirplus when confronted with 'ls -l' situations
- Soft mount bugfixes
- NFS over RDMA bugfixes
- NFSv4 close locking fixes
- Various NFSv4.x client state management optimisations
- Rename/unlink code cleanups"
* tag 'nfs-for-3.15-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (28 commits)
nfs: pass string length to pr_notice message about readdir loops
NFSv4: Fix a use-after-free problem in open()
SUNRPC: rpc_restart_call/rpc_restart_call_prepare should clear task->tk_status
SUNRPC: Don't let rpc_delay() clobber non-timeout errors
SUNRPC: Ensure call_connect_status() deals correctly with SOFTCONN tasks
SUNRPC: Ensure call_status() deals correctly with SOFTCONN tasks
NFSv4: Ensure we respect soft mount timeouts during trunking discovery
NFSv4: Schedule recovery if nfs40_walk_client_list() is interrupted
NFS: advertise only supported callback netids
SUNRPC: remove KERN_INFO from dprintk() call sites
SUNRPC: Fix large reads on NFS/RDMA
NFS: Clean up: revert increase in READDIR RPC buffer max size
SUNRPC: Ensure that call_bind times out correctly
SUNRPC: Ensure that call_connect times out correctly
nfs: emit a fsnotify_nameremove call in sillyrename codepath
nfs: remove synchronous rename code
nfs: convert nfs_rename to use async_rename infrastructure
nfs: make nfs_async_rename non-static
nfs: abstract out code needed to complete a sillyrename
NFSv4: Clear the open state flags if the new stateid does not match
...
There is no guarantee that the strings in the nfs_cache_array will be
NULL-terminated. In the event that we end up hitting a readdir loop, we
need to ensure that we pass the warning message the length of the
string.
Reported-by: Lachlan McIlroy <lmcilroy@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
There isn't much sense in maintaining two separate versions of rename
code. Convert nfs_rename to use the asynchronous rename infrastructure
that nfs_sillyrename uses, and emulate synchronous behavior by having
the task just wait on the reply.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Tested-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Try to detect 'ls -l' by having nfs_getattr() look at whether or not
there is an opendir() file descriptor for the parent directory.
If so, then assume that we want to force use of readdirplus in order
to avoid the multiple GETATTR calls over the wire.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Changes in commit a0b8cab3b9 ("mm: remove lru parameter from
__pagevec_lru_add and remove parts of pagevec API") have introduced a
call to add_to_page_cache_lru() which causes a leak in nfs_symlink() as
now the page gets an extra refcount that is not dropped.
Jan Stancek observed and reported the leak effect while running test8
from Connectathon Testsuite. After several iterations over the test
case, which creates several symlinks on a NFS mountpoint, the test
system was quickly getting into an out-of-memory scenario.
This patch fixes the page leak by dropping that extra refcount
add_to_page_cache_lru() is grabbing.
Signed-off-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Rafael Aquini <aquini@redhat.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Jeff Layton <jlayton@redhat.com>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: <stable@vger.kernel.org> [3.11.x+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the setting of NFS_INO_INVALIDATING gets reordered to before the
clearing of NFS_INO_INVALID_DATA, then another task may hit a race
window where both appear to be clear, even though the inode's pages are
still in need of invalidation. Fix this by adding the appropriate memory
barriers.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
There is a possible race in how the nfs_invalidate_mapping function is
handled. Currently, we go and invalidate the pages in the file and then
clear NFS_INO_INVALID_DATA.
The problem is that it's possible for a stale page to creep into the
mapping after the page was invalidated (i.e., via readahead). If another
writer comes along and sets the flag after that happens but before
invalidate_inode_pages2 returns then we could clear the flag
without the cache having been properly invalidated.
So, we must clear the flag first and then invalidate the pages. Doing
this however, opens another race:
It's possible to have two concurrent read() calls that end up in
nfs_revalidate_mapping at the same time. The first one clears the
NFS_INO_INVALID_DATA flag and then goes to call nfs_invalidate_mapping.
Just before calling that though, the other task races in, checks the
flag and finds it cleared. At that point, it trusts that the mapping is
good and gets the lock on the page, allowing the read() to be satisfied
from the cache even though the data is no longer valid.
These effects are easily manifested by running diotest3 from the LTP
test suite on NFS. That program does a series of DIO writes and buffered
reads. The operations are serialized and page-aligned but the existing
code fails the test since it occasionally allows a read to come out of
the cache incorrectly. While mixing direct and buffered I/O isn't
recommended, I believe it's possible to hit this in other ways that just
use buffered I/O, though that situation is much harder to reproduce.
The problem is that the checking/clearing of that flag and the
invalidation of the mapping really need to be atomic. Fix this by
serializing concurrent invalidations with a bitlock.
At the same time, we also need to allow other places that check
NFS_INO_INVALID_DATA to check whether we might be in the middle of
invalidating the file, so fix up a couple of places that do that
to look for the new NFS_INO_INVALIDATING flag.
Doing this requires us to be careful not to set the bitlock
unnecessarily, so this code only does that if it believes it will
be doing an invalidation.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
A fileid in NFS is a uint64. There are some occurrences where dprintk()
outputs a signed fileid. This leads to confusion and more difficult to
read debugging (negative fileids matching positive inode numbers).
Signed-off-by: Niels de Vos <ndevos@redhat.com>
CC: Santosh Pradhan <spradhan@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Pull vfs updates from Al Viro:
"All kinds of stuff this time around; some more notable parts:
- RCU'd vfsmounts handling
- new primitives for coredump handling
- files_lock is gone
- Bruce's delegations handling series
- exportfs fixes
plus misc stuff all over the place"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (101 commits)
ecryptfs: ->f_op is never NULL
locks: break delegations on any attribute modification
locks: break delegations on link
locks: break delegations on rename
locks: helper functions for delegation breaking
locks: break delegations on unlink
namei: minor vfs_unlink cleanup
locks: implement delegations
locks: introduce new FL_DELEG lock flag
vfs: take i_mutex on renamed file
vfs: rename I_MUTEX_QUOTA now that it's not used for quotas
vfs: don't use PARENT/CHILD lock classes for non-directories
vfs: pull ext4's double-i_mutex-locking into common code
exportfs: fix quadratic behavior in filehandle lookup
exportfs: better variable name
exportfs: move most of reconnect_path to helper function
exportfs: eliminate unused "noprogress" counter
exportfs: stop retrying once we race with rename/remove
exportfs: clear DISCONNECTED on all parents sooner
exportfs: more detailed comment for path_reconnect
...
Pull fs-cache fixes from David Howells:
Can you pull these commits to fix an issue with NFS whereby caching can be
enabled on a file that is open for writing by subsequently opening it for
reading. This can be made to crash by opening it for writing again if you're
quick enough.
The gist of the patchset is that the cookie should be acquired at inode
creation only and subsequently enabled and disabled as appropriate (which
dispenses with the backing objects when they're not needed).
The extra synchronisation that NFS does can then be dispensed with as it is
thenceforth managed by FS-Cache.
Could you send these on to Linus?
This likely will need fixing also in CIFS and 9P also once the FS-Cache
changes are upstream. AFS and Ceph are probably safe.
* 'fscache' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
NFS: Use i_writecount to control whether to get an fscache cookie in nfs_open()
FS-Cache: Provide the ability to enable/disable cookies
FS-Cache: Add use/unuse/wake cookie wrappers
This check was added by Al Viro with
d9e80b7de9 "nfs d_revalidate() is too
trigger-happy with d_drop()", with the explanation that we don't want to
remove the root of a disconnected tree, which will still be included on
the s_anon list.
But DCACHE_DISCONNECTED does *not* actually identify dentries that are
disconnected from the dentry tree or hashed on s_anon. IS_ROOT() is the
way to do that.
Also add a comment from Al's commit to remind us why this check is
there.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Use i_writecount to control whether to get an fscache cookie in nfs_open() as
NFS does not do write caching yet. I *think* this is the cause of a problem
encountered by Mark Moseley whereby __fscache_uncache_page() gets a NULL
pointer dereference because cookie->def is NULL:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
IP: [<ffffffff812a1903>] __fscache_uncache_page+0x23/0x160
PGD 0
Thread overran stack, or stack corrupted
Oops: 0000 [#1] SMP
Modules linked in: ...
CPU: 7 PID: 18993 Comm: php Not tainted 3.11.1 #1
Hardware name: Dell Inc. PowerEdge R420/072XWF, BIOS 1.3.5 08/21/2012
task: ffff8804203460c0 ti: ffff880420346640
RIP: 0010:[<ffffffff812a1903>] __fscache_uncache_page+0x23/0x160
RSP: 0018:ffff8801053af878 EFLAGS: 00210286
RAX: 0000000000000000 RBX: ffff8800be2f8780 RCX: ffff88022ffae5e8
RDX: 0000000000004c66 RSI: ffffea00055ff440 RDI: ffff8800be2f8780
RBP: ffff8801053af898 R08: 0000000000000001 R09: 0000000000000003
R10: 0000000000000000 R11: 0000000000000000 R12: ffffea00055ff440
R13: 0000000000001000 R14: ffff8800c50be538 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff88042fc60000(0063) knlGS:00000000e439c700
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000000000010 CR3: 0000000001d8f000 CR4: 00000000000607f0
Stack:
...
Call Trace:
[<ffffffff81365a72>] __nfs_fscache_invalidate_page+0x42/0x70
[<ffffffff813553d5>] nfs_invalidate_page+0x75/0x90
[<ffffffff811b8f5e>] truncate_inode_page+0x8e/0x90
[<ffffffff811b90ad>] truncate_inode_pages_range.part.12+0x14d/0x620
[<ffffffff81d6387d>] ? __mutex_lock_slowpath+0x1fd/0x2e0
[<ffffffff811b95d3>] truncate_inode_pages_range+0x53/0x70
[<ffffffff811b969d>] truncate_inode_pages+0x2d/0x40
[<ffffffff811b96ff>] truncate_pagecache+0x4f/0x70
[<ffffffff81356840>] nfs_setattr_update_inode+0xa0/0x120
[<ffffffff81368de4>] nfs3_proc_setattr+0xc4/0xe0
[<ffffffff81357f78>] nfs_setattr+0xc8/0x150
[<ffffffff8122d95b>] notify_change+0x1cb/0x390
[<ffffffff8120a55b>] do_truncate+0x7b/0xc0
[<ffffffff8121f96c>] do_last+0xa4c/0xfd0
[<ffffffff8121ffbc>] path_openat+0xcc/0x670
[<ffffffff81220a0e>] do_filp_open+0x4e/0xb0
[<ffffffff8120ba1f>] do_sys_open+0x13f/0x2b0
[<ffffffff8126aaf6>] compat_SyS_open+0x36/0x50
[<ffffffff81d7204c>] sysenter_dispatch+0x7/0x24
The code at the instruction pointer was disassembled:
> (gdb) disas __fscache_uncache_page
> Dump of assembler code for function __fscache_uncache_page:
> ...
> 0xffffffff812a18ff <+31>: mov 0x48(%rbx),%rax
> 0xffffffff812a1903 <+35>: cmpb $0x0,0x10(%rax)
> 0xffffffff812a1907 <+39>: je 0xffffffff812a19cd <__fscache_uncache_page+237>
These instructions make up:
ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX);
That cmpb is the faulting instruction (%rax is 0). So cookie->def is NULL -
which presumably means that the cookie has already been at least partway
through __fscache_relinquish_cookie().
What I think may be happening is something like a three-way race on the same
file:
PROCESS 1 PROCESS 2 PROCESS 3
=============== =============== ===============
open(O_TRUNC|O_WRONLY)
open(O_RDONLY)
open(O_WRONLY)
-->nfs_open()
-->nfs_fscache_set_inode_cookie()
nfs_fscache_inode_lock()
nfs_fscache_disable_inode_cookie()
__fscache_relinquish_cookie()
nfs_inode->fscache = NULL
<--nfs_fscache_set_inode_cookie()
-->nfs_open()
-->nfs_fscache_set_inode_cookie()
nfs_fscache_inode_lock()
nfs_fscache_enable_inode_cookie()
__fscache_acquire_cookie()
nfs_inode->fscache = cookie
<--nfs_fscache_set_inode_cookie()
<--nfs_open()
-->nfs_setattr()
...
...
-->nfs_invalidate_page()
-->__nfs_fscache_invalidate_page()
cookie = nfsi->fscache
-->nfs_open()
-->nfs_fscache_set_inode_cookie()
nfs_fscache_inode_lock()
nfs_fscache_disable_inode_cookie()
-->__fscache_relinquish_cookie()
-->__fscache_uncache_page(cookie)
<crash>
<--__fscache_relinquish_cookie()
nfs_inode->fscache = NULL
<--nfs_fscache_set_inode_cookie()
What is needed is something to prevent process #2 from reacquiring the cookie
- and I think checking i_writecount should do the trick.
It's also possible to have a two-way race on this if the file is opened
O_TRUNC|O_RDONLY instead.
Reported-by: Mark Moseley <moseleymark@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Determine if we've created a new file by examining the directory change
attribute and/or the O_EXCL flag.
This fixes a regression when doing a non-exclusive create of a new file.
If the FILE_CREATED flag is not set, the atomic_open() command will
perform full file access permissions checks instead of just checking
for MAY_OPEN.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Set FILE_CREATED on O_CREAT|O_EXCL. If the NFS server honored our request
for exclusivity then this must be correct.
Currently this is a no-op, since the VFS sets FILE_CREATED anyway. The
next patch will, however, require this flag to be always set by
filesystems.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Convert the filesystem shrinkers to use the new API, and standardise some
of the behaviours of the shrinkers at the same time. For example,
nr_to_scan means the number of objects to scan, not the number of objects
to free.
I refactored the CIFS idmap shrinker a little - it really needs to be
broken up into a shrinker per tree and keep an item count with the tree
root so that we don't need to walk the tree every time the shrinker needs
to count the number of objects in the tree (i.e. all the time under
memory pressure).
[glommer@openvz.org: fixes for ext4, ubifs, nfs, cifs and glock. Fixes are needed mainly due to new code merged in the tree]
[assorted fixes folded in]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Glauber Costa <glommer@openvz.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Carlos Maiolino <cmaiolino@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Rientjes <rientjes@google.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: J. Bruce Fields <bfields@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Kent Overstreet <koverstreet@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The sysctl knob sysctl_vfs_cache_pressure is used to determine which
percentage of the shrinkable objects in our cache we should actively try
to shrink.
It works great in situations in which we have many objects (at least more
than 100), because the aproximation errors will be negligible. But if
this is not the case, specially when total_objects < 100, we may end up
concluding that we have no objects at all (total / 100 = 0, if total <
100).
This is certainly not the biggest killer in the world, but may matter in
very low kernel memory situations.
Signed-off-by: Glauber Costa <glommer@openvz.org>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Carlos Maiolino <cmaiolino@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Rientjes <rientjes@google.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: J. Bruce Fields <bfields@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Kent Overstreet <koverstreet@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Highlights include:
- Fix NFSv4 recovery so that it doesn't recover lost locks in cases such as
lease loss due to a network partition, where doing so may result in data
corruption. Add a kernel parameter to control choice of legacy behaviour
or not.
- Performance improvements when 2 processes are writing to the same file.
- Flush data to disk when an RPCSEC_GSS session timeout is imminent.
- Implement NFSv4.1 SP4_MACH_CRED state protection to prevent other
NFS clients from being able to manipulate our lease and file lockingr
state.
- Allow sharing of RPCSEC_GSS caches between different rpc clients
- Fix the broken NFSv4 security auto-negotiation between client and server
- Fix rmdir() to wait for outstanding sillyrename unlinks to complete
- Add a tracepoint framework for debugging NFSv4 state recovery issues.
- Add tracing to the generic NFS layer.
- Add tracing for the SUNRPC socket connection state.
- Clean up the rpc_pipefs mount/umount event management.
- Merge more patches from Chuck in preparation for NFSv4 migration support.
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Merge tag 'nfs-for-3.12-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Highlights include:
- Fix NFSv4 recovery so that it doesn't recover lost locks in cases
such as lease loss due to a network partition, where doing so may
result in data corruption. Add a kernel parameter to control
choice of legacy behaviour or not.
- Performance improvements when 2 processes are writing to the same
file.
- Flush data to disk when an RPCSEC_GSS session timeout is imminent.
- Implement NFSv4.1 SP4_MACH_CRED state protection to prevent other
NFS clients from being able to manipulate our lease and file
locking state.
- Allow sharing of RPCSEC_GSS caches between different rpc clients.
- Fix the broken NFSv4 security auto-negotiation between client and
server.
- Fix rmdir() to wait for outstanding sillyrename unlinks to complete
- Add a tracepoint framework for debugging NFSv4 state recovery
issues.
- Add tracing to the generic NFS layer.
- Add tracing for the SUNRPC socket connection state.
- Clean up the rpc_pipefs mount/umount event management.
- Merge more patches from Chuck in preparation for NFSv4 migration
support"
* tag 'nfs-for-3.12-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (107 commits)
NFSv4: use mach cred for SECINFO_NO_NAME w/ integrity
NFS: nfs_compare_super shouldn't check the auth flavour unless 'sec=' was set
NFSv4: Allow security autonegotiation for submounts
NFSv4: Disallow security negotiation for lookups when 'sec=' is specified
NFSv4: Fix security auto-negotiation
NFS: Clean up nfs_parse_security_flavors()
NFS: Clean up the auth flavour array mess
NFSv4.1 Use MDS auth flavor for data server connection
NFS: Don't check lock owner compatability unless file is locked (part 2)
NFS: Don't check lock owner compatibility in writes unless file is locked
nfs4: Map NFS4ERR_WRONG_CRED to EPERM
nfs4.1: Add SP4_MACH_CRED write and commit support
nfs4.1: Add SP4_MACH_CRED stateid support
nfs4.1: Add SP4_MACH_CRED secinfo support
nfs4.1: Add SP4_MACH_CRED cleanup support
nfs4.1: Add state protection handler
nfs4.1: Minimal SP4_MACH_CRED implementation
SUNRPC: Replace pointer values with task->tk_pid and rpc_clnt->cl_clid
SUNRPC: Add an identifier for struct rpc_clnt
SUNRPC: Ensure rpc_task->tk_pid is available for tracepoints
...
Do have_submounts(), shrink_dcache_parent() and d_drop() atomically.
check_submounts_and_drop() can deal with negative dentries and
non-directories as well.
Non-directories can also be mounted on. And just like directories we don't
want these to disappear with invalidation.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
If an NFS client does
mkdir("dir");
fd = open("dir/file");
unlink("dir/file");
close(fd);
rmdir("dir");
then the asynchronous nature of the sillyrename operation means that
we can end up getting EBUSY for the rmdir() in the above test. Fix
that by ensuring that we wait for any in-progress sillyrenames
before sending the rmdir() to the server.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We don't want to pass the context argument to trace_nfs_atomic_open_exit()
after it has been released.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
When doing an open of a directory, ensure that we do pass the lookup flags
from nfs_atomic_open into nfs_lookup.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Add tracepoints for inode attribute updates, attribute revalidation,
writeback start/end fsync start/end, attribute change start/end,
permission check start/end.
The intention is to enable performance tracing using 'perf'as well as
improving debugging.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Ever since commit 6168f62cb (Add ACCESS operation to OPEN compound)
the NFSv4 atomic open has primed the access cache, and so nfs_permission
will no longer do an RPC call on the wire.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently, you can open a NFSv4 file with O_APPEND|O_DIRECT, but cannot
fcntl(F_SETFL,...) with those flags. This flag combination is explicitly
forbidden on NFSv3 opens, and it seems like it should also be on NFSv4.
Reported-by: Chao Ye <cye@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Make nfs_readdir revalidate only when we're at the beginning of the directory or
if the cached attributes have expired.
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
nfs_prime_dcache currently only sets the verifier when it doesn't
initially a matching dentry in the dcache. Set the verifier in the case
where we do find a dentry in the dcache. This ensures that we don't
have to look up the dentry again if we want to use it after a readdir.
Cc: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Feature highlights include:
- Add basic client support for NFSv4.2
- Add basic client support for Labeled NFS (selinux for NFSv4.2)
- Fix the use of credentials in NFSv4.1 stateful operations, and
add support for NFSv4.1 state protection.
Bugfix highlights:
- Fix another NFSv4 open state recovery race
- Fix an NFSv4.1 back channel session regression
- Various rpc_pipefs races
- Fix another issue with NFSv3 auth negotiation
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Merge tag 'nfs-for-3.11-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"Feature highlights include:
- Add basic client support for NFSv4.2
- Add basic client support for Labeled NFS (selinux for NFSv4.2)
- Fix the use of credentials in NFSv4.1 stateful operations, and add
support for NFSv4.1 state protection.
Bugfix highlights:
- Fix another NFSv4 open state recovery race
- Fix an NFSv4.1 back channel session regression
- Various rpc_pipefs races
- Fix another issue with NFSv3 auth negotiation
Please note that Labeled NFS does require some additional support from
the security subsystem. The relevant changesets have all been
reviewed and acked by James Morris."
* tag 'nfs-for-3.11-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (54 commits)
NFS: Set NFS_CS_MIGRATION for NFSv4 mounts
NFSv4.1 Refactor nfs4_init_session and nfs4_init_channel_attrs
nfs: have NFSv3 try server-specified auth flavors in turn
nfs: have nfs_mount fake up a auth_flavs list when the server didn't provide it
nfs: move server_authlist into nfs_try_mount_request
nfs: refactor "need_mount" code out of nfs_try_mount
SUNRPC: PipeFS MOUNT notification optimization for dying clients
SUNRPC: split client creation routine into setup and registration
SUNRPC: fix races on PipeFS UMOUNT notifications
SUNRPC: fix races on PipeFS MOUNT notifications
NFSv4.1 use pnfs_device maxcount for the objectlayout gdia_maxcount
NFSv4.1 use pnfs_device maxcount for the blocklayout gdia_maxcount
NFSv4.1 Fix gdia_maxcount calculation to fit in ca_maxresponsesize
NFS: Improve legacy idmapping fallback
NFSv4.1 end back channel session draining
NFS: Apply v4.1 capabilities to v4.2
NFSv4.1: Clean up layout segment comparison helper names
NFSv4.1: layout segment comparison helpers should take 'const' parameters
NFSv4: Move the DNS resolver into the NFSv4 module
rpc_pipefs: only set rpc_dentry_ops if d_op isn't already set
...
