Simplify page cache zeroing of segments of pages through 3 functions

zero_user_segments(page, start1, end1, start2, end2)

        Zeros two segments of the page. It takes the position where to
        start and end the zeroing which avoids length calculations and
	makes code clearer.

zero_user_segment(page, start, end)

        Same for a single segment.

zero_user(page, start, length)

        Length variant for the case where we know the length.

We remove the zero_user_page macro. Issues:

1. Its a macro. Inline functions are preferable.

2. The KM_USER0 macro is only defined for HIGHMEM.

   Having to treat this special case everywhere makes the
   code needlessly complex. The parameter for zeroing is always
   KM_USER0 except in one single case that we open code.

Avoiding KM_USER0 makes a lot of code not having to be dealing
with the special casing for HIGHMEM anymore. Dealing with
kmap is only necessary for HIGHMEM configurations. In those
configurations we use KM_USER0 like we do for a series of other
functions defined in highmem.h.

Since KM_USER0 is depends on HIGHMEM the existing zero_user_page
function could not be a macro. zero_user_* functions introduced
here can be be inline because that constant is not used when these
functions are called.

Also extract the flushing of the caches to be outside of the kmap.

[akpm@linux-foundation.org: fix nfs and ntfs build]
[akpm@linux-foundation.org: fix ntfs build some more]
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: <linux-ext4@vger.kernel.org>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Cc: David Chinner <dgc@sgi.com>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch should fix the issue seen on Alpha with unaligned accesses in
the new readdir code. By aligning each dirent to sizeof(u64) we'll avoid
unaligned accesses. To make doubly sure we're not hitting problems also
rearrange struct hack_dirent to avoid holes.

SGI-PV: 975411
SGI-Modid: xfs-linux-melb:xfs-kern:30302a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

After reading the directory contents into the temporary buffer, we grab
each dirent and pass it to filldir witht eh current offset of the dirent.
The current offset was not being set for the first dirent in the temporary
buffer, which coul dresult in bad offsets being set in the f_pos field
result in looping and duplicate entries being returned from readdir.

SGI-PV: 974905
SGI-Modid: xfs-linux-melb:xfs-kern:30282a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

This was broken by my '[XFS] simplify xfs_create/mknod/symlink prototype',
which assigned the re-shuffled ondisk dev_t back to the rdev variable in
xfs_vn_mknod. Because of that i_rdev is set to the ondisk dev_t instead of
the linux dev_t later down the function.

Fortunately the fix for it is trivial: we can just remove the assignment
because xfs_revalidate_inode has done the proper job before unlocking the
inode.

SGI-PV: 974873
SGI-Modid: xfs-linux-melb:xfs-kern:30273a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

The recent filldir regression fix was not putting the correct d_off in
each dirent. This was resulting in incorrect cookies being passed to dmapi
ioctls and the wrong offset appearing in the dirents. readdir was
unaffected as the filp->f_pos was being updated with the correct offset
and this was being written into the last dirent in each buffer. Fix the
XFS code to do the right thing.

SGI-PV: 973746
SGI-Modid: xfs-linux-melb:xfs-kern:30240a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

On last close of a file we purge blocks beyond eof. The same code is used
when we truncate the file size down. In this case we need to wait for any
pending I/Os for dirty pages beyond the new eof. For the last close case
we are not changing the file size and therefore do not need to wait for
any I/Os to complete. This fixes a performance bottleneck where writes
into the page cache and cache flushes can become mutually exclusive.

SGI-PV: 964002
SGI-Modid: xfs-linux-melb:xfs-kern:30220a
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NPeter Leckie <pleckie@sgi.com>

The recent I_LOCK->I_SYNC changes mistakenly changed xfs_ichgtime to look
at I_SYNC instead of I_LOCK. This was incorrect and prevents newly created
inodes from moving to the dirty list. Change this to the correct check
which is for I_NEW, not I_LOCK or I_SYNC so that behaviour is correct.

SGI-PV: 974225
SGI-Modid: xfs-linux-melb:xfs-kern:30204a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

Fix breakage caused by commit 83144186
that did not introduce the necessary call to set_freezable() in
xfs/linux-2.6/xfs_buf.c .

SGI-PV: 974224
SGI-Modid: xfs-linux-melb:xfs-kern:30203a
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

The current readdir implementation deadlocks on a btree buffers locks
because nfsd calls back into ->lookup from the filldir callback. The only
short-term fix for this is to revert to the old inefficient
double-buffering scheme.

SGI-PV: 973377
SGI-Modid: xfs-linux-melb:xfs-kern:30201a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

The radix tree based inode caches did away with the inode cluster hashes,
replacing them with a bunch of masking and gang lookups on the radix tree.

This masking got broken when moving the code to per-ag radix trees and
indexing by agino # rather than straight inode number. The result is
clustered inode writeback does not cluster and things can go extremely
slowly when there are lots of inodes to write.

Fix it up by comparing the agino # of the inode we just looked up to the
index of the cluster we are looking for.
Tested-by: NTorsten Kaiser <just.for.lkml@googlemail.com>

SGI-PV: 972915
SGI-Modid: xfs-linux-melb:xfs-kern:30033a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

SGI-PV: 972554
SGI-Modid: xfs-linux-melb:xfs-kern:30128a
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NChristoph Hellwig <hch@infradead.org>

- calculation of 'page_count' was incorrect as it did not
  consider the offset of 'mem' into the first page. The
  logic to bump 'page_count' didn't work if 'len' was <=
  PAGE_CACHE_SIZE (ie offset = 3k, len = 2k).
- setting b_buffer_length to 'len' is incorrect if 'offset'
  is > 0. Set it to the total length of the buffer.
- I suspect that passing a non-aligned address into
  mem_to_page() for the first page may have been causing
  issues - don't know but just tidy up that code anyway.

SGI-PV: 971596
SGI-Modid: xfs-linux-melb:xfs-kern:30143a
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NChristoph Hellwig <hch@infradead.org>

- sanity check for NULL user buffer in xfs_ioc_bulkstat[_compat]()
- remove the special case for XFS_IOC_FSBULKSTAT with count == 1. This
  special case causes bulkstat to fail because the special case uses
  xfs_bulkstat_single() instead of xfs_bulkstat() and the two functions
  have different semantics.  xfs_bulkstat() will return the next inode
  after the one supplied while skipping internal inodes (ie quota inodes).
  xfs_bulkstate_single() will only lookup the inode supplied and return
  an error if it is an internal inode.
- in xfs_bulkstat(), need to initialise 'lastino' to the inode supplied
  so in cases were we return without examining any inodes the scan wont
  restart back at zero.
- sanity check for valid *ubcountp values. Cannot sanity check for valid
  ubuffer here because some users of xfs_bulkstat() don't supply a buffer.
- checks against 'ubleft' (the space left in the user's buffer) should be
  against 'statstruct_size' which is the supplied minimum object size.
  The mixture of checks against statstruct_size and 0 was one of the
  reasons we were skipping inodes.
- if the formatter function returns BULKSTAT_RV_NOTHING and an error and
  the error is not ENOENT or EINVAL then we need to abort the scan. ENOENT
  is for inodes that are no longer valid and we just skip them. EINVAL is
  returned if we try to lookup an internal inode so we skip them too. For
  a DMF scan if the inode and DMF attribute cannot fit into the space left
  in the user's buffer it would return ERANGE. We didn't handle this error
  and skipped the inode. We would continue to skip inodes until one fitted
  into the user's buffer or we completed the scan.
- put back the recalculation of agino (that got removed with the last fix)
  at the end of the while loop. This is because the code at the start of
  the loop expects agino to be the last inode examined if it is non-zero.
- if we found some inodes but then encountered an error, return success
  this time and the error next time. If the formatter aborted with ENOMEM
  we will now return this error but only if we couldn't read any inodes.
  Previously if we encountered ENOMEM without reading any inodes we
  returned a zero count and no error which falsely indicated the scan was
  complete.

SGI-PV: 973431
SGI-Modid: xfs-linux-melb:xfs-kern:30089a
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NDavid Chinner <dgc@sgi.com>

The recent behaviour layer removal dropped the check for quotas that have
been requested at mount time but have subsequently been turned off. This
results in a panic when accessing m_quotainfo which has been freed.

This patch adds the check originally made by xfs_qm_syncall() to
xfs_qm_sync().

SGI-PV: 969769
SGI-Modid: xfs-linux-melb:xfs-kern:29908a
Signed-off-by: NDonald Douwsma <donaldd@sgi.com>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>

Now that nfsd has stopped writing to the find_exported_dentry member we an
mark the export_operations const
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: Neil Brown <neilb@suse.de>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: <linux-ext4@vger.kernel.org>
Cc: Dave Kleikamp <shaggy@austin.ibm.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: David Chinner <dgc@sgi.com>
Cc: Timothy Shimmin <tes@sgi.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Chris Mason <mason@suse.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: "Vladimir V. Saveliev" <vs@namesys.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This one is a lot more complicated than the previous ones.  XFS already had a
very clever scheme for supporting 64bit inode numbers in filehandles, and I've
reworked this to be some kind of a prototype for the generic 64bit inode
filehandle support.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: Neil Brown <neilb@suse.de>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: David Chinner <dgc@sgi.com>
Cc: Timothy Shimmin <tes@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently XFs has three different fid types: struct fid, struct xfs_fid
and struct xfs_fid2 with hte latter two beeing identicaly and the first
one beeing the same size but an unstructured array with the same size.

This patch consolidates all this to alway uuse struct xfs_fid.

This patch is required for an upcoming patch series from me that revamps
the nfs exporting code and introduces a Linux-wide struct fid.

SGI-PV: 970336
SGI-Modid: xfs-linux-melb:xfs-kern:29651a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

Fixup for lack of dmapi support and no quota module support.

SGI-PV: 969985
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NTim Shimmin <tes@sgi.com>

I_LOCK was used for several unrelated purposes, which caused deadlock
situations in certain filesystems as a side effect.  One of the purposes
now uses the new I_SYNC bit.

Also document the various bits and change their order from historical to
logical.

[bunk@stusta.de: make fs/inode.c:wake_up_inode() static]
Signed-off-by: NJoern Engel <joern@wohnheim.fh-wedel.de>
Cc: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: David Chinner <dgc@sgi.com>
Cc: Anton Altaparmakov <aia21@cam.ac.uk>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Miklos Szeredi <miklos@szeredi.hu> and me identified a writeback bug:

> The following strange behavior can be observed:
>
> 1. large file is written
> 2. after 30 seconds, nr_dirty goes down by 1024
> 3. then for some time (< 30 sec) nothing happens (disk idle)
> 4. then nr_dirty again goes down by 1024
> 5. repeat from 3. until whole file is written
>
> So basically a 4Mbyte chunk of the file is written every 30 seconds.
> I'm quite sure this is not the intended behavior.

It can be produced by the following test scheme:

# cat bin/test-writeback.sh
grep nr_dirty /proc/vmstat
echo 1 > /proc/sys/fs/inode_debug
dd if=/dev/zero of=/var/x bs=1K count=204800&
while true; do grep nr_dirty /proc/vmstat; sleep 1; done

# bin/test-writeback.sh
nr_dirty 19207
nr_dirty 19207
nr_dirty 30924
204800+0 records in
204800+0 records out
209715200 bytes (210 MB) copied, 1.58363 seconds, 132 MB/s
nr_dirty 47150
nr_dirty 47141
nr_dirty 47142
nr_dirty 47142
nr_dirty 47142
nr_dirty 47142
nr_dirty 47205
nr_dirty 47214
nr_dirty 47214
nr_dirty 47214
nr_dirty 47214
nr_dirty 47214
nr_dirty 47215
nr_dirty 47216
nr_dirty 47216
nr_dirty 47216
nr_dirty 47154
nr_dirty 47143
nr_dirty 47143
nr_dirty 47143
nr_dirty 47143
nr_dirty 47143
nr_dirty 47142
nr_dirty 47142
nr_dirty 47142
nr_dirty 47142
nr_dirty 47134
nr_dirty 47134
nr_dirty 47135
nr_dirty 47135
nr_dirty 47135
nr_dirty 46097 <== -1038
nr_dirty 46098
nr_dirty 46098
nr_dirty 46098
[...]
nr_dirty 46091
nr_dirty 46092
nr_dirty 46092
nr_dirty 45069 <== -1023
nr_dirty 45056
nr_dirty 45056
nr_dirty 45056
[...]
nr_dirty 37822
nr_dirty 36799 <== -1023
[...]
nr_dirty 36781
nr_dirty 35758 <== -1023
[...]
nr_dirty 34708
nr_dirty 33672 <== -1024
[...]
nr_dirty 33692
nr_dirty 32669 <== -1023

% ls -li /var/x
847824 -rw-r--r-- 1 root root 200M 2007-08-12 04:12 /var/x

% dmesg|grep 847824  # generated by a debug printk
[  529.263184] redirtied inode 847824 line 548
[  564.250872] redirtied inode 847824 line 548
[  594.272797] redirtied inode 847824 line 548
[  629.231330] redirtied inode 847824 line 548
[  659.224674] redirtied inode 847824 line 548
[  689.219890] redirtied inode 847824 line 548
[  724.226655] redirtied inode 847824 line 548
[  759.198568] redirtied inode 847824 line 548

# line 548 in fs/fs-writeback.c:
543                 if (wbc->pages_skipped != pages_skipped) {
544                         /*
545                          * writeback is not making progress due to locked
546                          * buffers.  Skip this inode for now.
547                          */
548                         redirty_tail(inode);
549                 }

More debug efforts show that __block_write_full_page()
never has the chance to call submit_bh() for that big dirty file:
the buffer head is *clean*. So basicly no page io is issued by
__block_write_full_page(), hence pages_skipped goes up.

Also the comment in generic_sync_sb_inodes():

544                         /*
545                          * writeback is not making progress due to locked
546                          * buffers.  Skip this inode for now.
547                          */

and the comment in __block_write_full_page():

1713                 /*
1714                  * The page was marked dirty, but the buffers were
1715                  * clean.  Someone wrote them back by hand with
1716                  * ll_rw_block/submit_bh.  A rare case.
1717                  */

do not quite agree with each other. The page writeback should be skipped for
'locked buffer', but here it is 'clean buffer'!

This patch fixes this bug. Though I'm not sure why __block_write_full_page()
is called only to do nothing and who actually issued the writeback for us.

This is the two possible new behaviors after the patch:

1) pretty nice: wait 30s and write ALL:)
2) not so good:
	- during the dd: ~16M
	- after 30s:      ~4M
	- after 5s:       ~4M
	- after 5s:     ~176M

The next patch will fix case (2).

Cc: David Chinner <dgc@sgi.com>
Cc: Ken Chen <kenchen@google.com>
Signed-off-by: NFengguang Wu <wfg@mail.ustc.edu.cn>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Slab constructors currently have a flags parameter that is never used.  And
the order of the arguments is opposite to other slab functions.  The object
pointer is placed before the kmem_cache pointer.

Convert

        ctor(void *object, struct kmem_cache *s, unsigned long flags)

to

        ctor(struct kmem_cache *s, void *object)

throughout the kernel

[akpm@linux-foundation.org: coupla fixes]
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

XFS leaves stray mappings around when it vmaps memory to make it virtually
contigious. This upsets Xen if one of those pages is being recycled into a
pagetable, since it finds an extra writable mapping of the page.

This patch solves the problem in a brute force way, by making XFS always
eagerly unmap its mappings.

SGI-PV: 971902
SGI-Modid: xfs-linux-melb:xfs-kern:29886a
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

Stop using xfs_getattr and a onstack bhv_vattr_t just to get three fields
from the underlying inode and opencode copying from the inode fields
instead.

SGI-PV: 970662
SGI-Modid: xfs-linux-melb:xfs-kern:29711a
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 leaves stray mappings around when it vmaps memory to make it
virtually contigious.  This upsets Xen if one of those pages is being
recycled into a pagetable, since it finds an extra writable mapping of
the page.

This patch solves the problem in a brute force way, by making XFS
always eagerly unmap its mappings.  David Chinner says this shouldn't
have any performance impact on filesystems with default block sizes;
it will only affect filesystems with large block sizes.
Signed-off-by: NJeremy Fitzhardinge <jeremy@xensource.com>
Acked-by: NDavid Chinner <dgc@sgi.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: XFS masters <xfs-masters@oss.sgi.com>
Cc: Stable kernel <stable@kernel.org>
Cc: Morten =?utf-8?q?B=C3=B8geskov?= <xen-users@morten.bogeskov.dk>
Cc: Mark Williamson <mark.williamson@cl.cam.ac.uk>

Signed-off-by: NNick Piggin <npiggin@suse.de>
Cc: David Chinner <dgc@sgi.com>
Cc: Timothy Shimmin <tes@sgi.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Because we cherrypicked SGI-Modid xfs-linux-melb:xfs-kern:29675a
and it depended on the sgi mod which removed io_vnode (which was
not cherrypicked in 23) it was hand modified.
This fixes things back up (to the originial mod) now we have moved
on again.
Reviewed-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

Removes STATIC on xfs_freeze function which was not manually
applied for SGI-Modid: xfs-linux-melb:xfs-kern:29504a.
Reviewed-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

Put back the QUEUE_ORDERED_NONE test which caused us grief in sles when it
was taken out as, IIRC, it allowed md/lvm to be thought of as supporting
barriers when they weren't in some configurations. This patch will be
reverting what went in as part of a change for the SGI-pv 964544
(SGI-Modid: xfs-linux-melb:xfs-kern:28568a).

SGI-PV: 971783
SGI-Modid: xfs-linux-melb:xfs-kern:29882a
Signed-off-by: NTim Shimmin <tes@sgi.com>
Signed-off-by: NDavid Chinner <dgc@sgi.com>

SGI-PV: 971603
SGI-Modid: xfs-linux-melb:xfs-kern:29871a
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

In xfs_fs_sync_super() treat a sync the same as a filesystem freeze. This
is needed to force the log to disk for inodes which are not marked dirty
in the Linux inode (the inodes are marked dirty on completion of the log
I/O) and so sync_inodes() will not flush them.

In xfs_fs_write_inode() a synchronous flush will not get an EAGAIN from
xfs_inode_flush() and if an asynchronous flush returns EAGAIN we should
pass it on to the caller. If we get an error while flushing the inode then
re-dirty it so we can try again later.

SGI-PV: 971670
SGI-Modid: xfs-linux-melb:xfs-kern:29860a
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

Here 'agino' increments through the inodes in an allocation group. At the
end of the innermost 'for' loop it will hold the value of the next inode
to look at (ie the first inode in the next cluster/chunk). Assigning
'lastino' to 'agino' resets it to the last inode in the last inode cluster
we just looked at. This causes us to look up the very same cluster and
examine all the inodes all over again, and again, and again...

We also want to set 'lastino' for the cases when we're not interested in
the inode so that the next call to bulkstat won't re-examine the same
uninteresting inodes.

SGI-PV: 971064
SGI-Modid: xfs-linux-melb:xfs-kern:29840a
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

Simplify the prototype for xfs_create/xfs_mkdir/xfs_symlink by not passing
down a bhv_vattr_t that just hogs stack space. Instead pass down the mode
in a mode_t and in case of xfs_create the rdev as a scalar type as well.

SGI-PV: 968563
SGI-Modid: xfs-linux-melb:xfs-kern:29794a
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 call into xfs_getattr and put a big bhv_vattr_t on the stack
just to get a little information from the XFS inode.

Add a helper called xfs_ioc_fsgetxattr instead that deals with retrieving
the information in a clean way.

SGI-PV: 968563
SGI-Modid: xfs-linux-melb:xfs-kern:29780a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

In the following scenario xfs_bulkstat() returns incorrect stale inode
state:

1. File_A is created and its inode synced to disk. 2. File_A is unlinked
and doesn't exist anymore. 3. Filesystem sync is invoked. 4. File_B is
created. File_B happens to reclaim File_A's inode. 5. xfs_bulkstat() is
called and detects File_B but reports the

incorrect File_A inode state.

Explanation for the incorrect inode state is that inodes are not
immediately synced on file create for performance reasons. This leaves the
on-disk inode buffer uninitialized (or with old state from a previous
generation inode) and this is what xfs_bulkstat() would report.

The patch marks the on-disk inode buffer "dirty" on unlink. When the inode
is reclaimed (by a new file create), xfs_bulkstat() would filter this
inode by the "dirty" mark. Once the inode is flushed to disk, the on-disk
buffer "dirty" mark is automatically removed and a following
xfs_bulkstat() would return the correct inode state.

Marking the on-disk inode buffer "dirty" on unlink is achieved by setting
the on-disk di_nlink field to 0. Note that the in-core di_nlink has
already been set to 0 and a corresponding transaction logged by
xfs_droplink(). This is an exception from the rule that any on-disk inode
buffer changes has to be followed by a disk write (inode flush).
Synchronizing the in-core to on-disk di_nlink values in advance (before
the actual inode flush to disk) should be fine in this case because the
inode is already unlinked and it would never change its di_nlink again for
this inode generation.

SGI-PV: 970842
SGI-Modid: xfs-linux-melb:xfs-kern:29757a
Signed-off-by: NVlad Apostolov <vapo@sgi.com>
Signed-off-by: NAlex Elder <aelder@sgi.com>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NMark Goodwin <markgw@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

SGI-PV: 968563
SGI-Modid: xfs-linux-melb:xfs-kern:29705a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

Fix for a regression caused by a recent patch
that moved the DMAPI mount option processing inside xfs_parseargs(). The
DMAPI mount option used to be processed in the DMAPI module loaded before
xfs_parseargs() was invoked.

SGI-PV: 970451
SGI-Modid: xfs-linux-melb:xfs-kern:29683a
Signed-off-by: NVlad Apostolov <vapo@sgi.com>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

Synchronous writes currently log inode changes before syncing pages to
disk. Since the file size is updated on I/O completion we wont be writing
out the updated file size and if we crash the file will have the wrong
size. This change moves the logging after the syncing of the pages to
ensure we log the correct file size.

SGI-PV: 970334
SGI-Modid: xfs-linux-melb:xfs-kern:29649a
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NTim Shimmin <tes@sgi.com>

m_growlock only needs plain binary mutex semantics, so use a struct mutex
instead of a semaphore for it.

SGI-PV: 968563
SGI-Modid: xfs-linux-melb:xfs-kern:29512a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

... or in the case of XLOG_TIC_ADD_OPHDR remove a useless macro entirely.

SGI-PV: 968563
SGI-Modid: xfs-linux-melb:xfs-kern:29511a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

Now that struct bhv_vfs doesn't have any members left we can kill it and
go directly from the super_block to the xfs_mount everywhere.

SGI-PV: 969608
SGI-Modid: xfs-linux-melb:xfs-kern:29509a
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>