The cache_change_attribute is used to decide whether or not a directory has
changed, in which case we may need to look it up again. Again, the use of
'jiffies' leads to an issue of resolution.
Once again, the fix is to change nfs_inode->cache_change_attribute, and
just make it a simple counter.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
It appears that 'jiffies' timestamps do not have high enough resolution for
nfs_inode_attrs_need_update(). One problem is that a GETATTR can be
launched within < 1 jiffy of the last operation that updated the attribute.
Another problem is that RPC calls can take < 1 jiffy to execute.
We can fix this by switching the variables to use a simple global counter
that gets incremented every time we start another GETATTR call.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Bruce observed that nfs_parse_ip_address() will successfully parse an
IPv6 address that looks like this:
"::1%"
A scope delimiter is present, but there is no scope ID following it.
This is harmless, as it would simply set the scope ID to zero. However,
in some cases we would like to flag this as an improperly formed
address.
We are now also careful to reject addresses where garbage follows the
address (up to the length of the string), instead of ignoring the
non-address characters; and where the scope ID is nonsense (not a valid
device name, but also not numeric). Before, both of these cases would
result in a harmless zero scope ID.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This fixes a regression seen when running the Connectathon testsuite
against an ext3 filesystem. The reason was that the inode was constantly
being marked as 'just updated' by the jiffy wraparound test.
This again meant that newer GETATTR calls were failing to pass the
nfs_inode_attrs_need_update() test unless the changes caused a ctime update
on the server, since they were perceived as having been started before the
latest inode update.
Given that nfs_inode_attrs_need_update() already checks for wraparound
of nfsi->last_updated, we can drop the buggy "protection" in
nfs_update_inode().
Also make a slight micro-optimisation of nfs_inode_attrs_need_update(): we
are more often going to see time_after(fattr->time_start, nfsi->last_updated)
be true, rather than seeing an update of ctime/size, so put that test
first to ensure that we optimise away the ctime/size tests.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This patch fixes a regression that was introduced by the string based mounts.
nfs_mount() statically returns -EACCES for every error returned
by the remote mounted. This is incorrect because -EACCES is
an non-fatal error to the mount.nfs command. This error causes
mount.nfs to retry the mount even in the case when the exported
directory does not exist.
This patch maps the errors returned by the remote mountd into
valid errno values, exactly how it was done pre-string based
mounts. By returning the correct errno enables mount.nfs
to do the right thing.
Signed-off-by: Steve Dickson <steved@redhat.com>
[Trond.Myklebust@netapp.com: nfs_stat_to_errno() now correctly returns
negative errors, so remove the sign change.]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The code incorrectly assumes here that the server name (or ip address)
is null-terminated. This can cause referrals to fail in some cases.
Also support ipv6 addresses.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We plan to use this function elsewhere.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Whoever wrote this had a bizarre allergy to for loops.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This function is a little longer and more deeply nested than necessary.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Allow mount to do authenticated mounts below the root of the exported tree.
The wording in RFC 2623, sec 2.3.2. allows fsinfo with UNIX authentication
on the root of the export. Mounts are not always done on the root
of the exported tree. Especially autoumounts often mount below the root of
the exported tree.
Some server implementations (justly) require full authentication for the
so-called deep mounts. The old code used AUTH_SYS only. This caused deep
mounts to fail on systems requiring stronger authentication..
The client should try both authentication types and use the first one that
succeeds.
This method was already partially implemented. This patch completes
the implementation for NFS2 and NFS3.
This patch was developed to allow Debian systems to automount home directories
on Solaris servers with krb5 authentication.
Tested on kernel 2.6.24-etchnhalf.1
Signed-off-by: E.G. Keizer <keie@few.vu.nl>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The fattrs used in the NFSv3 getacl/setacl calls are not being properly
initialized. This occasionally causes nfs_update_inode to fall into
NFSv4 specific codepaths when handling post-op attrs from these calls.
Thanks to Cai Qian for noticing the spurious NFSv4 messages in debug
output from a v3 mount...
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We *do* now allow bsd flocks over nfs.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Unfortunately, BUG_ON(IS_ROOT(dentry)) can happen inside
nfs_follow_mountpoint with NFS running Fedora 8 using a
specific setup.
https://bugzilla.redhat.com/show_bug.cgi?id=458622
So, the situation should be handled on NFS client gracefully.
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Trond Myklebust <Trond.Myklebust@netapp.com>
CC: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently, if two processes are both trying to revalidate metadata for the
same inode, they will find themselves being serialised. There is no good
justification for this now that we have improved our ability to detect
stale attribute data, so we should remove that serialisation.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If we're merely checking the inode attributes because we suspect that the
'updated' attributes returned by the RPC call are stale, then we shouldn't
be doing weak cache consistency updates or clearing the cache_validity
flags.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
In the case where there are parallel RPC calls to the same inode, we may
receive stale metadata due to the lack of ordering, hence the sanity
checking of metadata in nfs_refresh_inode().
Currently, __nfs_revalidate_inode() is calling nfs_update_inode() directly,
without any further sanity checks, and hence may end up setting the inode
up with stale metadata.
Fix is to use nfs_refresh_inode() instead of nfs_update_inode().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If we believe that the attributes are old (see nfs_refresh_inode()), then
we shouldn't force an update.
Also ensure that we hold the inode->i_lock across attribute checks and the
call to nfs_refresh_inode_locked() to ensure that we don't race with other
attribute updates.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Currently nfs_refresh_inode() will only update the inode metadata if it
sees that the RPC call that returned the nfs_fattr was started
after the last update of the inode. This means that if we have parallel
RPC calls to the same inode (when sending WRITE calls, for instance), we
may often miss updates.
This patch attempts to recover those missed updates by also accepting
them if the ctime in the nfs_fattr is more recent than the inode's
cached ctime.
It also recovers the case where the file size has increased, but the
ctime has not been updated due to limited ctime resolution.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Try to avoid taking and dropping the inode->i_lock more than once. Do so by
moving the code in nfs_refresh_inode() that needs to be done under the
spinlock into a function nfs_refresh_inode_locked(), and then having both
nfs_refresh_inode() and nfs_post_op_update_inode() call it directly.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The point of introducing text-based mounts was to allow us to add
functionality without having to worry about legacy binary mount formats.
The mask should be there in order to ensure that binary formats don't start
enabling features that they cannot support. There is no justification for
applying it to the text mount path.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Add the flag NFS_MOUNT_LOOKUP_CACHE_NONEG to turn off the caching of
negative dentries. In reality what we do is to force
nfs_lookup_revalidate() to always discard negative dentries.
Add the flag NFS_MOUNT_LOOKUP_CACHE_NONE for enforcing stricter
revalidation of dentries. It forces the revalidate code to always do a
lookup instead of just checking the cached mtime of the parent directory.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Instead of causing umount requests to block on server->active_wq while the
asynchronous sillyrename deletes are executing, we can use the sb->s_active
counter to obtain a reference to the super_block, and then release that
reference in nfs_async_unlink_release().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
After the BKL removal patches were applied to the rest of the NFS code, the
BKL protection in nfs_file_llseek() is no longer sufficient to ensure that
inode->i_size is read safely in generic_file_llseek_unlocked().
In order to fix the situation, we either have to replace the naked read of
inode->i_size in generic_file_llseek_unlocked() with i_size_read(), or the
whole thing needs to be executed under the inode->i_lock;
In order to avoid disrupting other filesystems, avoid touching
generic_file_llseek_unlocked() for now...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The previous patch db203d53d4 ("mm:
tiny-shmem fix lock ordering: mmap_sem vs i_mutex") to fix the lock
ordering in tiny-shmem breaks shared anonymous and IPC memory on NOMMU
architectures because it was using the expanding truncate to signal ramfs
to allocate a physically contiguous RAM backing the inode (otherwise it is
unusable for "memory mapping" it to userspace).
However do_truncate is what caused the lock ordering error, due to it
taking i_mutex. In this case, we can actually just call ramfs directly to
allocate memory for the mapping, rather than go via truncate.
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There's a race between mm->owner assignment and swapoff, more easily
seen when task slab poisoning is turned on. The condition occurs when
try_to_unuse() runs in parallel with an exiting task. A similar race
can occur with callers of get_task_mm(), such as /proc/<pid>/<mmstats>
or ptrace or page migration.
CPU0 CPU1
try_to_unuse
looks at mm = task0->mm
increments mm->mm_users
task 0 exits
mm->owner needs to be updated, but no
new owner is found (mm_users > 1, but
no other task has task->mm = task0->mm)
mm_update_next_owner() leaves
mmput(mm) decrements mm->mm_users
task0 freed
dereferencing mm->owner fails
The fix is to notify the subsystem via mm_owner_changed callback(),
if no new owner is found, by specifying the new task as NULL.
Jiri Slaby:
mm->owner was set to NULL prior to calling cgroup_mm_owner_callbacks(), but
must be set after that, so as not to pass NULL as old owner causing oops.
Daisuke Nishimura:
mm_update_next_owner() may set mm->owner to NULL, but mem_cgroup_from_task()
and its callers need to take account of this situation to avoid oops.
Hugh Dickins:
Lockdep warning and hang below exec_mmap() when testing these patches.
exit_mm() up_reads mmap_sem before calling mm_update_next_owner(),
so exec_mmap() now needs to do the same. And with that repositioning,
there's now no point in mm_need_new_owner() allowing for NULL mm.
Reported-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The VFS interface for the 'd_compare()' is a bit special (read: 'odd'),
because it really just essentially replaces a memcmp(). The filesystem
is supposed to just compare the two names with whatever case-independent
or other function.
And when I say 'is supposed to', I obviously mean that 'procfs does odd
things, and actually looks at the dentry that we don't even pass down,
rather than just the name'. Which results in problems, because we
actually call d_compare before we have even verified that the dentry is
still hashed at all.
And that causes a problm since the inode that procfs looks at may have
been free'd and the d_inode pointer is NULL. procfs just assumes that
all dentries are positive, since procfs itself never generates a
negative one. But memory pressure will still result in the dentry
getting torn down, and as it is removed by RCU, it still remains visible
on some lists - and to d_compare.
If the filesystem just did a name comparison, we wouldn't care. And we
could just fix procfs to know about negative dentries too. But rather
than have the low-level filesystems know about internal VFS details,
just move the check for a unhashed dentry up a bit, so that we will only
call d_compare on dentries that are still active.
The actual oops this caused didn't look like a NULL pointer dereference
because procfs did a 'container_of(inode, struct proc_inode, vfs_inode)'
to get at its internal proc_inode information from the inode pointer,
and accessed a field below the inode. So the oops would look something
like
BUG: unable to handle kernel paging request at fffffffffffffff0
IP: [<ffffffff802bc6c6>] proc_sys_compare+0x36/0x50
and was seen on both x86-64 (Alexey Dobriyan and Hugh Dickins) and
ppc64 (Hugh Dickins).
Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Hugh Dickins <hugh@veritas.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-of-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'linux-next' of git://git.infradead.org/~dedekind/ubifs-2.6:
UBIFS: fix printk format warnings
UBIFS: remove incorrect assert
UBIFS: TNC / GC race fixes
UBIFS: create the name of the background thread in every case
Yet another bug was found in xfs_iext_irec_compact_full() and while the
source of the bug was found it wasn't an easy task to track it down
because the conditions are very difficult to reproduce.
A HUGE thank-you goes to Russell Cattelan and Eric Sandeen for their
significant effort in tracking down the source of this corruption.
xfs_iext_irec_compact_full() and xfs_iext_irec_compact_pages() are almost
identical - they both compact indirect extent lists by moving extents from
subsequent buffers into earlier ones. xfs_iext_irec_compact_pages() only
moves extents if all of the extents in the next buffer will fit into the
empty space in the buffer before it. xfs_iext_irec_compact_full() will go
a step further and move part of the next buffer if all the extents wont
fit. It will then shift the remaining extents in the next buffer up to the
start of the buffer. The bug here was that we did not update er_extoff and
this caused extent list corruption.
It does not appear that this extra functionality gains us much. Calling
xfs_iext_irec_compact_pages() instead will do a good enough job at
compacting the indirect list and will be quicker too.
For the case in xfs_iext_indirect_to_direct() the total number of extents
in the indirect list will fit into one buffer so we will never need the
extra functionality of xfs_iext_irec_compact_full() there.
Also xfs_iext_irec_compact_pages() doesn't need to do a memmove() (the
buffers will never overlap) so we don't want the performance hit that can
incur.
SGI-PV: 987159
SGI-Modid: xfs-linux-melb:xfs-kern:32166a
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
If we don't move all the records from the next buffer into the current
buffer then we need to update the er_extoff field of the next buffer as we
shift the remaining records to the start of the buffer.
SGI-PV: 987159
SGI-Modid: xfs-linux-melb:xfs-kern:32165a
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Russell Cattelan <cattelan@thebarn.com>
In case of error, the function p9_client_walk returns an ERR pointer, but
never returns a NULL pointer. So a NULL test that comes after an IS_ERR
test should be deleted.
The semantic match that finds this problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@match_bad_null_test@
expression x, E;
statement S1,S2;
@@
x = p9_client_walk(...)
... when != x = E
* if (x != NULL)
S1 else S2
// </smpl>
Signed-off-by: Julien Brunel <brunel@diku.dk>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
fs/ubifs/dir.c:428: warning: format '%llu' expects type 'long long
unsigned int', but argument 5 has type 'long unsigned int'
fs/ubifs/debug.c:541: warning: format '%llu' expects type 'long long
unsigned int', but argument 2 has type 'long unsigned int'
Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
The assert was not valid because one of the variables
'taken_empty_lebs' has transient values out of sync
with the other variables.
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
- update GC sequence number if any nodes may have been moved
even if GC did not finish the LEB
- don't ignore error return when reading
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
If the ubifs partition is mounted RO and then remounted RW we end
up with no thread name in ubifs_remount_rw() and the thread appears
nameless.
Signed-off-by: Sebastian Siewior <bigeasy@linutronix.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
When unreserving space with boundaries that are not block aligned we round
up the start and round down the end boundaries and then use this function,
xfs_zero_remaining_bytes(), to zero the parts of the blocks that got
dropped during the rounding. The problem is we don't consider if these
blocks are beyond eof. Worse still is if we encounter delayed allocations
beyond eof we will try to use the magic delayed allocation block number as
a real block number. If the file size is ever extended to expose these
blocks then we'll go through xfs_zero_eof() to zero them anyway.
SGI-PV: 983683
SGI-Modid: xfs-linux-melb:xfs-kern:32055a
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
We have a use-after-free issue where log completions access buffers via
the buffer log item and the buffer has already been freed. Fix this by
taking a reference on the buffer when attaching the buffer log item and
release the hold when the buffer log item is detached and we no longer
need the buffer. Also create a new function xfs_buf_item_free() to combine
some common code.
SGI-PV: 985757
SGI-Modid: xfs-linux-melb:xfs-kern:32025a
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
If we call xfs_lock_two_inodes() to grab both the iolock and the ilock,
then drop the ilocks on both inodes, then grab them again (as
xfs_swap_extents() does) then lockdep will report a locking order problem.
This is a false positive.
To avoid this, disallow xfs_lock_two_inodes() fom locking both inode locks
at once - force calers to make two separate calls. This means that nested
dropping and regaining of the ilocks will retain the same lockdep subclass
and so lockdep will not see anything wrong with this code.
SGI-PV: 986238
SGI-Modid: xfs-linux-melb:xfs-kern:31999a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Peter Leckie <pleckie@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
The current code in xlog_iodone() uses the wrong macro to check if the
barrier has been cleared due to an EOPNOTSUPP error form the lower layer.
SGI-PV: 986143
SGI-Modid: xfs-linux-melb:xfs-kern:31984a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Nathaniel W. Turner <nate@houseofnate.net>
Signed-off-by: Peter Leckie <pleckie@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
With the help from some tracing I found that we try to map extents beyond
eof when doing a direct I/O read. It appears that the way to inform the
generic direct I/O path (ie do_direct_IO()) that we have breached eof is
to return an unmapped buffer from xfs_get_blocks_direct(). This will cause
do_direct_IO() to jump to the hole handling code where is will check for
eof and then abort.
This problem was found because a direct I/O read was trying to map beyond
eof and was encountering delayed allocations. The delayed allocations
beyond eof are speculative allocations and they didn't get converted when
the direct I/O flushed the file because there was only enough space in the
current AG to convert and write out the dirty pages within eof. Note that
xfs_iomap_write_allocate() wont necessarily convert all the delayed
allocation passed to it - it will return after allocating the first extent
- so if the delayed allocation extends beyond eof then it will stay that
way.
SGI-PV: 983683
SGI-Modid: xfs-linux-melb:xfs-kern:31929a
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Logically we would return an error in xfs_fs_remount code to prevent users
from believing they might have changed mount options using remount which
can't be changed.
But unfortunately mount(8) adds all options from mtab and fstab to the
mount arguments in some cases so we can't blindly reject options, but have
to check for each specified option if it actually differs from the
currently set option and only reject it if that's the case.
Until that is implemented we return success for every remount request, and
silently ignore all options that we can't actually change.
SGI-PV: 985710
SGI-Modid: xfs-linux-melb:xfs-kern:31908a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Memory allocations for log->l_grant_trace and iclog->ic_trace are done on
demand when the first event is logged. In xlog_state_get_iclog_space() we
call xlog_trace_iclog() under a spinlock and allocating memory here can
cause us to sleep with a spinlock held and deadlock the system.
For the log grant tracing we use KM_NOSLEEP but that means we can lose
trace entries. Since there is no locking to serialize the log grant
tracing we could race and have multiple allocations and leak memory.
So move the allocations to where we initialize the log/iclog structures.
Use KM_NOFS to avoid recursing into the filesystem and drop log->l_trace
since it's not even used.
SGI-PV: 983738
SGI-Modid: xfs-linux-melb:xfs-kern:31896a
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
