Revert
commit e8ced39d5e
Author: Mingming Cao <cmm@us.ibm.com>
Date: Fri Jul 11 19:27:31 2008 -0400
percpu_counter: new function percpu_counter_sum_and_set
As described in
revert "percpu counter: clean up percpu_counter_sum_and_set()"
the new percpu_counter_sum_and_set() is racy against updates to the
cpu-local accumulators on other CPUs. Revert that change.
This means that ext4 will be slow again. But correct.
Reported-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: <linux-ext4@vger.kernel.org>
Cc: <stable@kernel.org> [2.6.27.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Revert
commit 1f7c14c62c
Author: Mingming Cao <cmm@us.ibm.com>
Date: Thu Oct 9 12:50:59 2008 -0400
percpu counter: clean up percpu_counter_sum_and_set()
Before this patch we had the following:
percpu_counter_sum(): return the percpu_counter's value
percpu_counter_sum_and_set(): return the percpu_counter's value, copying
that value into the central value and zeroing the per-cpu counters before
returning.
After this patch, percpu_counter_sum_and_set() has gone, and
percpu_counter_sum() gets the old percpu_counter_sum_and_set()
functionality.
Problem is, as Eric points out, the old percpu_counter_sum_and_set()
functionality was racy and wrong. It zeroes out counters on "other" cpus,
without holding any locks which will prevent races agaist updates from
those other CPUS.
This patch reverts 1f7c14c62c. This means
that percpu_counter_sum_and_set() still has the race, but
percpu_counter_sum() does not.
Note that this is not a simple revert - ext4 has since started using
percpu_counter_sum() for its dirty_blocks counter as well.
Note that this revert patch changes percpu_counter_sum() semantics.
Before the patch, a call to percpu_counter_sum() will bring the counter's
central counter mostly up-to-date, so a following percpu_counter_read()
will return a close value.
After this patch, a call to percpu_counter_sum() will leave the counter's
central accumulator unaltered, so a subsequent call to
percpu_counter_read() can now return a significantly inaccurate result.
If there is any code in the tree which was introduced after
e8ced39d5e was merged, and which depends
upon the new percpu_counter_sum() semantics, that code will break.
Reported-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mingming Cao <cmm@us.ibm.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The patch 6341c39 "tracehook: exec" introduced a small regression in
2.6.27 regarding binfmt_misc exec event reporting. Since the reporting
is now done in the common search_binary_handler() function, an exec
of a misc binary will result in two (or possibly multiple) exec events
being reported, instead of just a single one, because the misc handler
contains a recursive call to search_binary_handler.
To add to the confusion, if PTRACE_O_TRACEEXEC is not active, the multiple
SIGTRAP signals will in fact cause only a single ptrace intercept, as the
signals are not queued. However, if PTRACE_O_TRACEEXEC is on, the debugger
will actually see multiple ptrace intercepts (PTRACE_EVENT_EXEC).
The test program included below demonstrates the problem.
This change fixes the bug by calling tracehook_report_exec() only in the
outermost search_binary_handler() call (bprm->recursion_depth == 0).
The additional change to restore bprm->recursion_depth after each binfmt
load_binary call is actually superfluous for this bug, since we test the
value saved on entry to search_binary_handler(). But it keeps the use of
of the depth count to its most obvious expected meaning. Depending on what
binfmt handlers do in certain cases, there could have been false-positive
tests for recursion limits before this change.
/* Test program using PTRACE_O_TRACEEXEC.
This forks and exec's the first argument with the rest of the arguments,
while ptrace'ing. It expects to see one PTRACE_EVENT_EXEC stop and
then a successful exit, with no other signals or events in between.
Test for kernel doing two PTRACE_EVENT_EXEC stops for a binfmt_misc exec:
$ gcc -g traceexec.c -o traceexec
$ sudo sh -c 'echo :test:M::foobar::/bin/cat: > /proc/sys/fs/binfmt_misc/register'
$ echo 'foobar test' > ./foobar
$ chmod +x ./foobar
$ ./traceexec ./foobar; echo $?
==> good <==
foobar test
0
$
==> bad <==
foobar test
unexpected status 0x4057f != 0
3
$
*/
#include <stdio.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/ptrace.h>
#include <unistd.h>
#include <signal.h>
#include <stdlib.h>
static void
wait_for (pid_t child, int expect)
{
int status;
pid_t p = wait (&status);
if (p != child)
{
perror ("wait");
exit (2);
}
if (status != expect)
{
fprintf (stderr, "unexpected status %#x != %#x\n", status, expect);
exit (3);
}
}
int
main (int argc, char **argv)
{
pid_t child = fork ();
if (child < 0)
{
perror ("fork");
return 127;
}
else if (child == 0)
{
ptrace (PTRACE_TRACEME);
raise (SIGUSR1);
execv (argv[1], &argv[1]);
perror ("execve");
_exit (127);
}
wait_for (child, W_STOPCODE (SIGUSR1));
if (ptrace (PTRACE_SETOPTIONS, child,
0L, (void *) (long) PTRACE_O_TRACEEXEC) != 0)
{
perror ("PTRACE_SETOPTIONS");
return 4;
}
if (ptrace (PTRACE_CONT, child, 0L, 0L) != 0)
{
perror ("PTRACE_CONT");
return 5;
}
wait_for (child, W_STOPCODE (SIGTRAP | (PTRACE_EVENT_EXEC << 8)));
if (ptrace (PTRACE_CONT, child, 0L, 0L) != 0)
{
perror ("PTRACE_CONT");
return 6;
}
wait_for (child, W_EXITCODE (0, 0));
return 0;
}
Reported-by: Arnd Bergmann <arnd@arndb.de>
CC: Ulrich Weigand <ulrich.weigand@de.ibm.com>
Signed-off-by: Roland McGrath <roland@redhat.com>
None of this code appears to be used anywhere so remove it.
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
While 440037287c "[PATCH] switch all filesystems over to
d_obtain_alias" removed some cases where fh_to_dentry() and
fh_to_parent() could return NULL, there are still a few NULL returns
left in individual filesystems. Thus it was a mistake for that commit
to remove the handling of NULL returns in the callers.
Revert those parts of 440037287c which removed the NULL handling.
(We could, alternatively, modify all implementations to return -ESTALE
instead of NULL, but that proves to require fixing a number of
filesystems, and in some cases it's arguably more natural to return
NULL.)
Thanks to David for original patch and Linus, Christoph, and Hugh for
review.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: David Howells <dhowells@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Impact: build fix on Alpha
-tip testing found this build failure on the Alpha defconfig:
/home/mingo/tip/fs/proc/stat.c: In function 'show_stat':
/home/mingo/tip/fs/proc/stat.c:48: error: implicit declaration of function 'for_each_irq_desc'
/home/mingo/tip/fs/proc/stat.c:48: error: expected ';' before '{' token
can not use irq_desc() in stat.c on older architectures.
Signed-off-by: Yinghai Lu <yinghai@kernel.orgg>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: new feature
Problem on distro kernels: irq_desc[NR_IRQS] takes megabytes of RAM with
NR_CPUS set to large values. The goal is to be able to scale up to much
larger NR_IRQS value without impacting the (important) common case.
To solve this, we generalize irq_desc[NR_IRQS] to an (optional) array of
irq_desc pointers.
When CONFIG_SPARSE_IRQ=y is used, we use kzalloc_node to get irq_desc,
this also makes the IRQ descriptors NUMA-local (to the site that calls
request_irq()).
This gets rid of the irq_cfg[] static array on x86 as well: irq_cfg now
uses desc->chip_data for x86 to store irq_cfg.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Changeset a238b790d5 (Call fasync()
functions without the BKL) introduced a race which could leave
file->f_flags in a state inconsistent with what the underlying
driver/filesystem believes. Revert that change, and also fix the same
races in ioctl_fioasync() and ioctl_fionbio().
This is a minimal, short-term fix; the real fix will not involve the
BKL.
Reported-by: Oleg Nesterov <oleg@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/bdev:
[PATCH] fix bogus argument of blkdev_put() in pktcdvd
[PATCH 2/2] documnt FMODE_ constants
[PATCH 1/2] kill FMODE_NDELAY_NOW
[PATCH] clean up blkdev_get a little bit
[PATCH] Fix block dev compat ioctl handling
[PATCH] kill obsolete temporary comment in swsusp_close()
When project quota is active and is being used for directory tree
quota control, we disallow rename outside the current directory
tree. This requires a check to be made after all the inodes
involved in the rename are locked. We fail to unlock the inodes
correctly if we disallow the rename when the target is outside the
current directory tree. This results in a hang on the next access
to the inodes involved in failed rename.
Reported-by: Arkadiusz Miskiewicz <arekm@maven.pl>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Tested-by: Arkadiusz Miskiewicz <arekm@maven.pl>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Hit this assert because an inode was tagged with XFS_ICI_RECLAIM_TAG but
not XFS_IRECLAIMABLE|XFS_IRECLAIM. This is because xfs_iget_cache_hit()
first clears XFS_IRECLAIMABLE and then calls __xfs_inode_clear_reclaim_tag()
while only holding the pag_ici_lock in read mode so we can race with
xfs_reclaim_inodes_ag(). Looks like xfs_reclaim_inodes_ag() will do the
right thing anyway so just remove the assert.
Thanks to Christoph for pointing out where the problem was.
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
entries_size is probably left over from when we used to pass the
size to kmem_free().
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
We check the return value of all other calls to xfs_buf_get_noaddr().
Make sense to do it here too.
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
When project quota is active and is being used for directory tree
quota control, we disallow rename outside the current directory
tree. This requires a check to be made after all the inodes
involved in the rename are locked. We fail to unlock the inodes
correctly if we disallow the rename when the target is outside the
current directory tree. This results in a hang on the next access
to the inodes involved in failed rename.
Reported-by: Arkadiusz Miskiewicz <arekm@maven.pl>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Tested-by: Arkadiusz Miskiewicz <arekm@maven.pl>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Update FMODE_NDELAY before each ioctl call so that we can kill the
magic FMODE_NDELAY_NOW. It would be even better to do this directly
in setfl(), but for that we'd need to have FMODE_NDELAY for all files,
not just block special files.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The way the bd_claim for the FMODE_EXCL case is implemented is rather
confusing. Clean it up to the most logical style.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Conflicts:
fs/nfsd/nfs4recover.c
Manually fixed above to use new creds API functions, e.g.
nfs4_save_creds().
Signed-off-by: James Morris <jmorris@namei.org>
Move the inode tracing into xfs_iget.c / xfs_inode.h and kill xfs_vnode.c
now that it's empty.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
The whole machinery to wait on I/O completion is related to the I/O path
and should be there instead of in xfs_vnode.c. Also give the functions
more descriptive names.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
There's just one caller of this helper, and it's much cleaner to just merge
the xfs_do_force_shutdown call into it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
There's almost nothing left in this function, instead remove the IRELE
on the real times inodes and the call to XFS_QM_UNMOUNT into xfs_unmountfs.
For the regular unmount case that means it now also happenes after dmapi
notification, but otherwise there is no difference in behaviour.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
Currently we explicitly call xfs_iflush on the quota, real-time and root
inodes from xfs_unmount_flush. But we just called xfs_sync_inodes with
SYNC_ATTR and do an XFS_bflush aka xfs_flush_buftarg to make sure all inodes
are on disk already, so there is no need for these special cases.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
Use xfs_trans_ijoin in xfs_trans_iget in case we need to join an inode into
a transaction instead of opencoding it. Based on a discussion with and an
incomplete patch from Niv Sardi.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
We never supported shared read-only filesystems, so remove the dead
code left over from IRIX for it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
There are a few inode flags around that aren't used anywhere, so remove
them. Also update xfsidbg to display all used inode flags correctly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
The various inlines in xfs_sb.h that deal with the superblock version
and fature flags were converted from macros a while ago, and this
show by the odd coding style full of useless braces and backslashes
and the avoidance of conditionals.
Clean these up to look like normal C code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Donald Douwsma <donaldd@sgi.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
All but one caller of xlog_state_want_sync drop and re-acquire
l_icloglock around the call to it, just so that xlog_state_want_sync can
acquire and drop it.
Move all lock operation out of l_icloglock and assert that the lock is
held when it is called.
Note that it would make sense to extende this scheme to
xlog_state_release_iclog, but the locking in there is more complicated
and we'd like to keep the atomic_dec_and_lock optmization for those
callers not having l_icloglock yet.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
->link is guranteed to get an already reference inode passed so we
can do a simple increment of i_count instead of using igrab and thus
avoid banging on the global inode_lock. This is what most filesystems
already do.
Also move the increment after the call to xfs_link to simplify error
handling.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
xfs_buf_iostart is a "shared" helper for xfs_buf_read_flags,
xfs_bawrite, and xfs_bdwrite - except that there isn't much shared
code but rather special cases for each caller.
So remove this function and move the functionality to the caller.
xfs_bawrite and xfs_bdwrite are now big enough to be moved out of
line and the xfs_buf_read_flags is moved into a new helper called
_xfs_buf_read.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
Merge xfs_iextract and xfs_idestroy into xfs_ireclaim as they are never
called individually. Also rewrite most comments in this area as they
were severly out of date.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
When mnt_want_write was introduced a call to it was added around
xfs_ichgtime, but there is no need for this because a file can't be open
read/write on a r/o mount, and a mount can't degrade r/o while we still
have files open for writing. As the mnt_want_write changes were never
merged into the CVS tree this patch is for mainline only.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
The recent compat patches make xfs_file.c include xfs_ioctl32.h unconditional,
which breaks the build on 32 bit systems which don't have the various compat
defintions.
Remove the include and move the defintion of xfs_file_compat_ioctl to
xfs_ioctl.h so that we can avoid including all the compat defintions in
xfs_file.c
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
* 'for-2.6.28' of git://linux-nfs.org/~bfields/linux:
NLM: client-side nlm_lookup_host() should avoid matching on srcaddr
nfsd: use of unitialized list head on error exit in nfs4recover.c
Add a reference to sunrpc in svc_addsock
nfsd: clean up grace period on early exit
* 'linux-next' of git://git.infradead.org/ubifs-2.6:
UBIFS: pre-allocate bulk-read buffer
UBIFS: do not allocate too much
UBIFS: do not print scary memory allocation warnings
UBIFS: allow for gaps when dirtying the LPT
UBIFS: fix compilation warnings
MAINTAINERS: change UBI/UBIFS git tree URLs
UBIFS: endian handling fixes and annotations
UBIFS: remove printk
Put things in IMHO a more readable order, now
that it's all done; add some comments.
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Add a compat handler for XFS_IOC_FSSETDM_BY_HANDLE.
I haven't tested this, lacking dmapi tools to do so
(unless xfsqa magically gets this somehow?)
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Add a compat handler for XFS_IOC_ATTRMULTI_BY_HANDLE
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Add a compat handler for XFS_IOC_ATTRLIST_BY_HANDLE
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
The XFS_IOC_FSBULKSTAT_SINGLE ioctl passes in the
desired inode number, while XFS_IOC_FSBULKSTAT passes
in the previous/last-stat'd inode number. The
compat handler wasn't differentiating these, so
when a XFS_IOC_FSBULKSTAT_SINGLE request for inode
128 was sent in, stat information for 131 was sent out.
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
The 32-bit xfs_blkstat_one handler was failing because
a size check checked whether the remaining (32-bit)
user buffer was less than the (64-bit) bulkstat buffer,
and failed with ENOMEM if so. Move this check
into the respective handlers so that they check the
correct sizes.
Also, the formatters were returning negative errors
or positive bytes copied; this was odd in the positive
error value world of xfs, and handled wrong by at least
some of the callers, which treated the bytes returned
as an error value. Move the bytes-used assignment
into the formatters.
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
