The only caller (xfs_fs_fill_super) can simplify call igrab on the root
inode.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30393a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

To get the read-only bind mounts in -mm to work correctly with XFS we need
to call the drop_nlink and inc_nlink helpers to monitor the link count.
Add calls to these to xfs_bumplink and xfs_droplink and stop copying over
di_nlink to i_nlink in xfs_validate_fields and vn_revalidate.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30392a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

The VFS doesn't use i_blocks, it's only used by generic_fillattr and the
generic quota code which XFS doesn't use. In XFS there is one use to check
whether we have an inline or out of line sumlink, but we can replace that
with a check of the XFS_IFINLINE inode flag.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30391a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

Checking the entire AIL on every insert and remove is prohibitively
expensive - the sustained sequntial create rate on a single disk drops
from about 1800/s to 60/s because of this checking resulting in the
xfslogd becoming cpu bound.

By default on debug builds, only check the next and previous entries in
the list to ensure they are ordered correctly. If you really want, define
XFS_TRANS_DEBUG to use the old behaviour.

SGI-PV: 972759
SGI-Modid: xfs-linux-melb:xfs-kern:30372a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

When many hundreds to thousands of threads all try to do simultaneous
transactions and the log is in a tail-pushing situation (i.e. full), we
can get multiple threads walking the AIL list and contending on the AIL
lock.

The AIL push is, in effect, a simple I/O dispatch algorithm complicated by
the ordering constraints placed on it by the transaction subsystem. It
really does not need multiple threads to push on it - even when only a
single CPU is pushing the AIL, it can push the I/O out far faster that
pretty much any disk subsystem can handle.

So, to avoid contention problems stemming from multiple list walkers, move
the list walk off into another thread and simply provide a "target" to
push to. When a thread requires a push, it sets the target and wakes the
push thread, then goes to sleep waiting for the required amount of space
to become available in the log.

This mechanism should also be a lot fairer under heavy load as the waiters
will queue in arrival order, rather than queuing in "who completed a push
first" order.

Also, by moving the pushing to a separate thread we can do more
effectively overload detection and prevention as we can keep context from
loop iteration to loop iteration. That is, we can push only part of the
list each loop and not have to loop back to the start of the list every
time we run. This should also help by reducing the number of items we try
to lock and/or push items that we cannot move.

Note that this patch is not intended to solve the inefficiencies in the
AIL structure and the associated issues with extremely large list
contents. That needs to be addresses separately; parallel access would
cause problems to any new structure as well, so I'm only aiming to isolate
the structure from unbounded parallelism here.

SGI-PV: 972759
SGI-Modid: xfs-linux-melb:xfs-kern:30371a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

Now that all direct caller of xfs_iaccess are gone we can kill xfs_iaccess
and xfs_access and just use generic_permission with a check_acl callback.
This is required for the per-mount read-only patchset in -mm to work
properly with XFS.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30370a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

xfs_swapext should simplify check if we have a writeable file descriptor
instead of re-checking the permissions using xfs_iaccess. Add an
additional check to refuse O_APPEND file descriptors because swapext is
not an append-only write operation.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30369a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

- stop using vnodes
- use proper multiple label goto unwinding
- give the struct file * variables saner names

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30366a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

Both callers of xfs_change_file_space alreaedy do the file->f_mode &
FMODE_WRITE check to ensure we have a file descriptor that has been opened
for write mode, so there is no need to re-check that with xfs_iaccess.
Especially as the later might wrongly deny it for corner cases like file
descriptor passing through unix domain sockets.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30365a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

A problem was reported where a system panicked in log recovery due to a
corrupt log record. The cause of the corruption is not known but this
change will at least prevent a crash for this specific scenario. Log
recovery definitely needs some more work in this area.

SGI-PV: 974151
SGI-Modid: xfs-linux-melb:xfs-kern:30318a
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NChristoph Hellwig <hch@infradead.org>

- merge xfs_fid2 into it's only caller xfs_dm_inode_to_fh.
- remove xfs_vget and opencode it in the two callers, simplifying
  both of them by avoiding the awkward calling convetion.
- assign directly to the dm_fid_t members in various places in the
  dmapi code instead of casting them to xfs_fid_t first (which
  is identical to dm_fid_t)

SGI-PV: 974747
SGI-Modid: xfs-linux-melb:xfs-kern:30258a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NVlad Apostolov <vapo@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

xfs_lowbit64 was broken on 32 bit platforms in a recent cleanup of the xfs
bitops. Fix it back up again.

SGI-PV: 974005
SGI-Modid: xfs-linux-melb:xfs-kern:30202a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

Currently XFS_IFORK_* and XFS_DFORK* are implemented by means of
XFS_CFORK* macros. But given that XFS_IFORK_* operates on an xfs_inode
that embedds and xfs_icdinode_core and XFS_DFORK_* operates on an
xfs_dinode that embedds a xfs_dinode_core one will have to do endian
swapping while the other doesn't. Instead of having the current mess with
the CFORK macros that have byteswapping and non-byteswapping version
(which are inconsistantly named while we're at it) just define each family
of the macros to stand by itself and simplify the whole matter.

A few direct references to the CFORK variants were cleaned up to use IFORK
or DFORK to make this possible.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30163a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NTim Shimmin <tes@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

There is no need to lock any page in xfs_buf.c because we operate on our
own address_space and all locking is covered by the buffer semaphore. If
we ever switch back to main blockdeive address_space as suggested e.g. for
fsblock with a similar scheme the locking will have to be totally revised
anyway because the current scheme is neither correct nor coherent with
itself.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30156a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30098a
Signed-off-by: NRobert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

The BPCSHIFT based macros, btoc*, ctob*, offtoc* and ctooff are either not
used or don't need to be used. The NDPP, NDPP, NBBY macros don't need to
be used but instead are replaced directly by PAGE_SIZE and PAGE_CACHE_SIZE
where appropriate. Initial patch and motivation from Nicolas Kaiser.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30096a
Signed-off-by: NTim Shimmin <tes@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

This assert is bogus. We can have a forced shutdown occur
between the check for the XLOG_FORCED_SHUTDOWN and the ASSERT. Also, the
logging system shouldn't care about the state of XFS_FORCED_SHUTDOWN, it
should only check XLOG_FORCED_SHUTDOWN. The logging system has it's own
forced shutdown flag so, for the case of a forced shutdown that's not due
to a logging error, we can flush the log.

SGI-PV: 972985
SGI-Modid: xfs-linux-melb:xfs-kern:30029a
Signed-off-by: NNiv Sardi <xaiki@sgi.com>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

Use XFS_IS_REALTIME_INODE in more places, and #define it to 0 if
CONFIG_XFS_RT is off. This should be safe because mount checks in
xfs_rtmount_init:

so if we get mounted w/o CONFIG_XFS_RT, no realtime inodes should be
encountered after that.

Defining XFS_IS_REALTIME_INODE to 0 saves a bit of stack space,
presumeably gcc can optimize around the various "if (0)" type checks:

xfs_alloc_file_space -8 xfs_bmap_adjacent -16 xfs_bmapi -8
xfs_bmap_rtalloc -16 xfs_bunmapi -28 xfs_free_file_space -64 xfs_imap +8
<-- ? hmm. xfs_iomap_write_direct -12 xfs_qm_dqusage_adjust -4
xfs_qm_vop_chown_reserve -4

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30014a
Signed-off-by: NEric Sandeen <sandeen@sandeen.net>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

Mount option parsing is platform specific. Move it out of core code into
the platform specific superblock operation file.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30012a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

Implement the new generic callout for file preallocation. Atomically
change the file size if requested.

SGI-PV: 972756
SGI-Modid: xfs-linux-melb:xfs-kern:30009a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

The log force added in xfs_iget_core() has been a performance issue since
it was introduced for tight loops that allocate then unlink a single file.
under heavy writeback, this can introduce unnecessary latency due tothe
log I/o getting stuck behind bulk data writes.

Fix this latency problem by avoinding the need for the log force by moving
the place we mark linux inode dirty to the transaction commit rather than
on transaction completion.

This also closes a potential hole in the sync code where a linux inode is
not dirty between the time it is modified and the time the log buffer has
been written to disk.

SGI-PV: 972753
SGI-Modid: xfs-linux-melb:xfs-kern:30007a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

Prevent transaction overrun in xfs_iomap_write_allocate() if we race with
a truncate that overlaps the delalloc range we were planning to allocate.

If we race, we may allocate into a hole and that requires block
allocation. At this point in time we don't have a reservation for block
allocation (apart from metadata blocks) and so allocating into a hole
rather than a delalloc region results in overflowing the transaction block
reservation.

Fix it by only allowing a single extent to be allocated at a time.

SGI-PV: 972757
SGI-Modid: xfs-linux-melb:xfs-kern:30005a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

There are several mount options that don't show up in /proc/mounts. Add
them in and clean up the showargs code at the same time.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30004a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

Sparse trips over the locking order in xlog_recover_do_efd_trans() when
xfs_trans_delete_ail() drops the ail lock. Because the unlock is
conditional, we need to either annotate with a "fake unlock" or change the
structure of the code so sparse thinks the function always unlocks.

Reordering the code makes it simpler, so do that.

SGI-PV: 972755
SGI-Modid: xfs-linux-melb:xfs-kern:30003a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

These are mostly locking annotations, marking things static, casts where
needed and declaring stuff in header files.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30002a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

Patch inspired by Andi Kleen.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30000a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

We need xfs_bulkstat() to report inode stat for inodes with link count
zero but reference count non zero.

The fix here:

http://oss.sgi.com/archives/xfs/2007-09/msg00266.html

changed this behavior and made xfs_bulkstat() to filter all unlinked
inodes including those that are not destroyed yet but held by reference.

The attached patch returns back to the original behavior by marking the
on-disk inode buffer "dirty" when di_mode is cleared (at that time both
inode link and reference counter are zero).

SGI-PV: 972004
SGI-Modid: xfs-linux-melb:xfs-kern:29914a
Signed-off-by: NVlad Apostolov <vapo@sgi.com>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

SGI-PV: 971596
SGI-Modid: xfs-linux-melb:xfs-kern:29902a
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

XFS_IOC_GETVERSION, XFS_IOC_GETXFLAGS and XFS_IOC_SETXFLAGS all take a
"long" which changes size between 32 and 64 bit platforms.

So, the ioctl cmds that come in from a 32-bit app aren't as expected, for
example on GETXFLAGS,

unknown cmd fd(3) cmd(80046601){t:'f';sz:4}

due to the size mismatch.

So, use instead the 32-bit version of the commands for compat ioctls, and
other than that it doesn't take any more manipulation.

Also, for both native and compat versions, just define them to the values
as defined in fs.h

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:29849a
Signed-off-by: NEric Sandeen <sandeen@sandeen.net>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

No need for xfs to have its own hex dumping routine now that the kernel
has one.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:29847a
Signed-off-by: NEric Sandeen <sandeen@sandeen.net>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

This macro is unused an all other acros in this family operate on native
types, so we most likely won't grow a user either.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:29846a
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

There is no need to lock any page in xfs_buf.c because we operate on our
own address_space and all locking is covered by the buffer semaphore. If
we ever switch back to main blockdeive address_space as suggested e.g. for
fsblock with a similar scheme the locking will have to be totally revised
anyway because the current scheme is neither correct nor coherent with
itself.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:29845a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

Refactoring xfs_mountfs() to call sub-functions for logical chunks can
help save a bit of stack, and can make it easier to read this long
function.

The mount path is one of the longest common callchains, easily getting to
within a few bytes of the end of a 4k stack when over lvm, quotas are
enabled, and quotacheck must be done.

With this change on top of the other stack-related changes I've sent, I
can get xfs to survive a normal xfsqa run on 4k stacks over lvm.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:29834a
Signed-off-by: NEric Sandeen <sandeen@sandeen.net>
Signed-off-by: NDonald Douwsma <donaldd@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

Mostly trivial conversion with one exceptions: h_num_logops was kept in
native endian previously and only converted to big endian in xlog_sync,
but we always keep it big endian now. With todays cpus fast byteswap
instructions that's not an issue but the new variant keeps the code clean
and maintainable.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:29821a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

- the various assign lsn macros are replaced by a single inline,
xlog_assign_lsn, which is equivalent to ASSIGN_ANY_LSN_HOST except
for a more sane calling convention. ASSIGN_LSN_DISK is replaced
by xlog_assign_lsn and a manual bytespap, and ASSIGN_LSN by the same,
except we pass the cycle and block arguments explicitly instead of a
log paramter. The latter two variants only had 2, respectively one
user anyway.
- the GET_CYCLE is replaced by a xlog_get_cycle inline with exactly the
same calling conventions.
- GET_CLIENT_ID is replaced by xlog_get_client_id which leaves away
the unused arch argument. Instead of conditional defintions
depending on host endianess we now do an unconditional swap and shift
then, which generates equal code.
- the unused XLOG_SET macro is removed.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:29820a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

- the various assign lsn macros are replaced by a single inline,
xlog_assign_lsn, which is equivalent to ASSIGN_ANY_LSN_HOST except
for a more sane calling convention. ASSIGN_LSN_DISK is replaced
by xlog_assign_lsn and a manual bytespap, and ASSIGN_LSN by the same,
except we pass the cycle and block arguments explicitly instead of a
log paramter. The latter two variants only had 2, respectively one
user anyway.
- the GET_CYCLE is replaced by a xlog_get_cycle inline with exactly the
same calling conventions.
- GET_CLIENT_ID is replaced by xlog_get_client_id which leaves away
the unused arch argument. Instead of conditional defintions
depending on host endianess we now do an unconditional swap and shift
then, which generates equal code.
- the unused XLOG_SET macro is removed.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:29819a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

No need to have a wrapper just two call two more functions.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:29816a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NDonald Douwsma <donaldd@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

Get rid of vnode useage in xfs_iget.c and pass Linux inode / xfs_inode
where apropinquate. And kill some useless helpers while we're at it.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:29808a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

xfs_ioctl.c passes around vnode pointers quite a lot, but all places
already have the Linux inode which is identical to the vnode these days.
Clean the code up to always use the Linux inode.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:29807a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

We were already filling the Linux struct statfs anyway, and doing this
trivial task directly in xfs_fs_statfs makes the code quite a bit cleaner.
While I was at it I also moved copying attributes that don't change over
the lifetime of the filesystem outside the superblock lock.

xfs_fs_fill_super used to get the magic number and blocksize through
xfs_statvfs, but assigning them directly is a lot cleaner and will save
some stack space during mount.

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:29802a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NTim Shimmin <tes@sgi.com>