It's an internal implementation detail which we _should_ be free to change.
So we did, and it promptly broke.
The compiler shold be able to work out when to use the __constant version
anyway.
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Based upon a bug report by Andrew Gallatin on netdev
with subject "CPU utilization increased in 2.6.27rc"
In commit 37437bb2e1
("pkt_sched: Schedule qdiscs instead of netdev_queue.")
the test of the queue being stopped was erroneously
removed from qdisc_run().
When the TX queue of the device fills up, this omission
causes lots of extraneous useless work to be queued up
to softirq context, where we'll just return immediately
because the device is still stuffed up.
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexey Dobriyan wrote:
> On Thu, Aug 07, 2008 at 07:00:56PM +0200, John Gumb wrote:
>> Scenario: no ipv6 default route set.
>
>> # ip -f inet6 route get fec0::1
>>
>> BUG: unable to handle kernel NULL pointer dereference at 00000000
>> IP: [<c0369b85>] rt6_fill_node+0x175/0x3b0
>> EIP is at rt6_fill_node+0x175/0x3b0
>
> 0xffffffff80424dd3 is in rt6_fill_node (net/ipv6/route.c:2191).
> 2186 } else
> 2187 #endif
> 2188 NLA_PUT_U32(skb, RTA_IIF, iif);
> 2189 } else if (dst) {
> 2190 struct in6_addr saddr_buf;
> 2191 ====> if (ipv6_dev_get_saddr(ip6_dst_idev(&rt->u.dst)->dev,
> ^^^^^^^^^^^^^^^^^^^^^^^^
> NULL
>
> 2192 dst, 0, &saddr_buf) == 0)
> 2193 NLA_PUT(skb, RTA_PREFSRC, 16, &saddr_buf);
> 2194 }
The commit that changed this can't be reverted easily, but the patch
below works for me.
Fix NULL de-reference in rt6_fill_node() when there's no IPv6 input
device present in the dst entry.
Signed-off-by: Brian Haley <brian.haley@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Data length has to be aligned in the budgeting request. Code
in xattr.c did not do this.
Signed-off-by: Zoltan Sogor <weth@inf.u-szeged.hu>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Use "if (0) printk()" construct in debugging print macros to
make the debugging messages be checked even if debugging is
off.
This patch also removes some unneeded spaces and blank lines.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
UBIFS does not presently re-use inode numbers, so leaving
i_generation zero is most appropriate for now.
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
At the moment UBIFS reserves twice old index size space for the
index. But this is not enough in some cases, because if the indexing
node are very fragmented and there are many small gaps, while the
dirty index has big znodes - in-the-gaps method would fail.
Thus, reserve trise as more, in which case we are guaranteed that
we can commit in any case.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
UBIFS aligns node lengths to 8, so budgeting has to do the
same. Well, direntry, inode, and page budgets are already
aligned, but not inode data budget (e.g., data in special
devices or symlinks). Do this for inode data as well.
Also, add corresponding debugging checks.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Budgeting is a crucial UBIFS subsystem - add more assertions
to improve requests checking. This is not compiled in when
UBIFS debugging is disabled.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
The debug function that checks orphans, does so using the
TNC mutex. That means it will not see a correct picture
if the inode is removed from the orphan tree before it is
removed from TNC.
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
The values in these two fields need to be preserved independently
and so a union cannot be used.
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Every time anything is deleted, UBIFS writes the deletion inode
node twice - once in 'ubifs_jnl_update()' and the second time in
'ubifs_jnl_write_inode()'. However, the second write is not needed
if no commit happened after 'ubifs_jnl_update()'. This patch
checks that condition and avoids writing the deletion inode for
the second time.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Increment the commit number at the beginnig of the commit, instead
of doing this after the commit. This is needed for further
optimizations.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
The 'last_reference' parameter of 'pack_inode()' is not really
needed because 'inode->i_nlink' may be tested instead. Zap it.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Simplify 'ubifs_jnl_write_inode()' by removing the 'deletion'
parameter which is not really needed because we may test
inode->i_nlink and check whether this is a deletion or not.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Orphan inodes are deleted inodes which will disappear after FS
re-mount. There is not need to write orphan inodes back, because
they are not needed on the flash media.
So optimize orphans a little by not writing them back. Just mark
them as clean, free the budget, and report success to VFS.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
We use ubifs_ro_mode() quite a lot, and not in fast-path, so
there is no reason to blow the code up by having it inlined.
Also, we usually want R/O mode change to be seen to other
CPUs as soon as possible, so when we make this a function
call, we will automatically have a memory barrier.
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
UBI transparently handles write errors by automatically copying
and remapping the affected eraseblock. If UBI is unable to do
that, for example its pool of eraseblocks reserved for bad block
handling is empty, then the error is propagated to UBIFS. UBIFS
must protect the media from falling into an inconsistent state
by immediately switching to read-only mode. In the case of log
updates, this was not being done.
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
UBIFS recovery testing debug facility simulates media failures.
When simulating an IO error, the error code returned must be
-EIO but it was not always if the user switched off the
debug recovery testing option at the same time.
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
Although the inode is marked as clean when it is being deleted,
it might stay and be used as orphan, and be marked as dirty.
So we have to free the budget when we delete it.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
The 'ubifs_release_dirty_inode_budget()' was buggy and incorrectly
freed the budget, which led to not freeing all dirty data budget.
This patch fixes that.
Also, this patch fixes ubifs_mkdir() which passed 1 in dirty_ino_d,
which makes no sense. Well, it is harmless though.
Also, add few more useful assertions. And improve few debugging
messages.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
We encouredge people to mount using volume name, not device
numbers. So print the name of the mounted UBI volume, not just
IDs.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
The ticket allocation code got reworked in 2.6.26 and we now free tickets
whereas before we used to cache them so the use-after-free went
undetected.
SGI-PV: 985525
SGI-Modid: xfs-linux-melb:xfs-kern:31877a
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>
Use KM_NOFS to prevent recursion back into the filesystem which can cause
deadlocks.
In the case of xfs_iread() we hold the lock on the inode cluster buffer
while allocating memory for the trace buffers. If we recurse back into XFS
to flush data that may require a transaction to allocate extents which
needs log space. This can deadlock with the xfsaild thread which can't
push the tail of the log because it is trying to get the inode cluster
buffer lock.
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31838a
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>
Use KM_MAYFAIL for the m_perag allocation, we can deal with the error
easily and blocking forever during mount is not a good idea either.
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31837a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
xfs_mount_free mostly frees the perag data, which is something that is
duplicated in the mount error path.
Move the XFS_QM_DONE call to the caller and remove the useless
mutex_destroy/spinlock_destroy calls so that we can re-use it for the
mount error path. Also rename it to xfs_free_perag to reflect what it
does.
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31836a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
xfs_readsb is called before xfs_mount so xfs_freesb should be called after
xfs_unmountfs, too. This means it now happens after a few things during
the of xfs_unmount which all have nothing to do with the superblock.
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31835a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
xfs_unmounts can't and shouldn't return errors so declare it as returning
void.
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31833a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Remove all the useless flags and code keyed off it in xfs_mountfs.
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31831a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
The root inode is allocated in xfs_mountfs so it should be release in
xfs_unmountfs. For the unmount case that means we do it after the the
xfs_sync(mp, SYNC_WAIT | SYNC_CLOSE) in the forced shutdown case and the
dmapi unmount event. Note that both reference the rip variable which might
be freed by that time in case inode flushing has kicked in, so strictly
speaking this might count as a bug fix
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31830a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
xfs_ichtime updates the xfs_inode and Linux inode timestamps just fine, no
need to call file_update_time and then copy the values over to the XFS
inode. The only additional thing in file_update_time are checks not
applicable to the write path.
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31829a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>
Port a little optmization from file_update_time to xfs_ichgtime, and only
update the timestamp and mark the inode dirty if the timestamp actually
changes in the timer tick resultion supported by the running kernel.
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31827a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
In xfs_ialloc we just want to set all timestamps to the current time. We
don't need to mark the inode dirty like xfs_ichgtime does, and we don't
need nor want the opimizations in xfs_ichgtime that I will introduce in
the next patch.
So just opencode the timestamp update in xfs_ialloc, and remove the new
unused XFS_ICHGTIME_ACC case in xfs_ichgtime.
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31825a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Now that all users of the sema_t are gone from XFS we can finally kill it.
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31823a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Use the new completion flush code to implement the dquot flush lock.
Removes one of the final users of semaphores in the XFS code base.
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31822a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Use the new completion flush code to implement the inode flush lock.
Removes one of the final users of semaphores in the XFS code base.
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31817a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
XFS object flushing doesn't quite match existing completion semantics. It
mixed exclusive access with completion. That is, we need to mark an object as
being flushed before flushing it to disk, and then block any other attempt to
flush it until the completion occurs. We do this but adding an extra count to
the completion before we start using them. However, we still need to
determine if there is a completion in progress, and allow no-blocking attempts
fo completions to decrement the count.
To do this we introduce:
int try_wait_for_completion(struct completion *x)
returns a failure status if done == 0, otherwise decrements done
to zero and returns a "started" status. This is provided
to allow counted completions to begin safely while holding
object locks in inverted order.
int completion_done(struct completion *x)
returns 1 if there is no waiter, 0 if there is a waiter
(i.e. a completion in progress).
This replaces the use of semaphores for providing this exclusion
and completion mechanism.
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31816a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
The xfs_buf_t b_iodonesema is really just a semaphore that wants to be a
completion. Change it to a completion and remove the last user of the
sema_t from XFS.
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31815a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
A lot of code has been converted away from semaphores, but there are still
comments that reference semaphore behaviour. The log code is the worst
offender. Update the comments to reflect what the code really does now.
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31814a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
The alloc and inobt btree use the same agbp/agno pair in the btree_cur
union. Make them use the same bc_private.a union member so that code for
these two short form btree implementations can be shared.
SGI-PV: 981498
SGI-Modid: xfs-linux-melb:xfs-kern:31788a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
