For CRC enabled filesystems, we can't just swap inode forks from one
inode to another when defragmenting a file - the blocks in the inode
fork bmap btree contain pointers back to the owner inode. Hence if
we are to swap the inode forks we have to atomically modify every
block in the btree during the transaction.

We are doing an entire fork swap here, so we could create a new
transaction item type that indicates we are changing the owner of a
certain structure from one value to another. If we combine this with
ordered buffer logging to modify all the buffers in the tree, then
we can change the buffers in the tree without needing log space for
the operation. However, this then requires log recovery to perform
the modification of the owner information of the objects/structures
in question.

This does introduce some interesting ordering details into recovery:
we have to make sure that the owner change replay occurs after the
change that moves the objects is made, not before. Hence we can't
use a separate log item for this as we have no guarantee of strict
ordering between multiple items in the log due to the relogging
action of asynchronous transaction commits. Hence there is no
"generic" method we can use for changing the ownership of arbitrary
metadata structures.

For inode forks, however, there is a simple method of communicating
that the fork contents need the owner rewritten - we can pass a
inode log format flag for the fork for the transaction that does a
fork swap. This flag will then follow the inode fork through
relogging actions so when the swap actually gets replayed the
ownership can be changed immediately by log recovery.  So that gives
us a simple method of "whole fork" exchange between two inodes.

This is relatively simple to implement, so it makes sense to do this
as an initial implementation to support xfs_fsr on CRC enabled
filesytems in the same manner as we do on existing filesystems. This
commit introduces the swapext driven functionality, the recovery
functionality will be in a separate patch.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Calling xfs_dir3_leaf_hdr_from_disk() in a verifier before
validating the magic numbers in the buffer results in ASSERT
failures due to mismatching magic numbers when a corruption occurs.
Seeing as the verifier is supposed to catch the corruption and pass
it back to the caller, having the verifier assert fail on error
defeats the purpose of detecting the errors in the first place.

Check the magic numbers direct from the buffer before decoding the
header.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NBen Myers <bpm@sgi.com>

A couple of simple locking annotations and 0 vs NULL warnings.
Nothing that changes any code behaviour, just removes build noise.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NBen Myers <bpm@sgi.com>

sparse reports:

fs/xfs/xfs_log_recover.c:2017:24: sparse: cast to restricted __be64

Because I used the wrong structure for the on-disk superblock cast
in 50d5c8d8 ("xfs: check LSN ordering for v5 superblocks during
recovery"). Fix it.

Reported-by: kbuild test robot
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NBen Myers <bpm@sgi.com>

So move it to a header file shared with userspace.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

So fix up the export in xfs_dir2.h that is needed by userspace.

<sigh>

Now xfs_dir3_sfe_put_ino has been made static. Revert 98f7462c ("xfs:
xfs_dir3_sfe_put_ino can be static") to being non static so that the
code shared with userspace is identical again.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBen Myers <bpm@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

This ASSERT is testing an if_flags flag value against
a di_aformat enum value.  di_aformat is never assigned
XFS_IFINLINE.

This happens to work for now, because XFS_IFINLINE has
the same value as XFS_DINODE_FMT_LOCAL, and that's tested
just before we call this function.

However, I think the intention is to assert that we have
read in the data, i.e. XFS_IFINLINE on if_flags, before
we use if_data.  This is done in other places through the
code as well.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NBen Myers <bpm@sgi.com>

In optimising the CIL operations, some of the IOP_* macros for
calling log item operations were removed. Remove the rest of them as
Christoph requested.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NGeoffrey Wehrman <gwehrman@sgi.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

We've been seeing occasional problems with log space leaks and
transaction underruns such as this for some time:

 XFS (dm-0): xlog_write: reservation summary:
   trans type  = FSYNC_TS (36)
   unit res    = 2740 bytes
   current res = -4 bytes
   total reg   = 0 bytes (o/flow = 0 bytes)
   ophdrs      = 0 (ophdr space = 0 bytes)
   ophdr + reg = 0 bytes
   num regions = 0

Turns out that xfstests generic/311 is reliably reproducing this
problem with the test it runs at sequence 16 of it execution. It is
a 100% reliable reproducer with the mkfs configuration of "-b
size=1024 -m crc=1" on a 10GB scratch device.

The problem? Inode forks in btree format are logged in memory
format, not disk format (i.e. bmbt format, not bmdr format). That
means there is a btree block header being logged, when such a
structure is never written to the inode fork in bmdr format. The
bmdr header in the inode is only 4 bytes, while the bmbt header is
24 bytes for v4 filesystems and 72 bytes for v5 filesystems.

We currently reserve the inode size plus the rounded up overhead of
a logging a buffer, which is 128 bytes. That means the reservation
for a 512 byte inode is 640 bytes. What we can actually log is:

	inode core, data and attr fork = 512 bytes
	inode log format + log op header = 56 + 12 = 68 bytes
	data fork bmbt hdr = 24/72 bytes
	attr fork bmbt hdr = 24/72 bytes

So, for a v2 inodes we can log at least 628 bytes, but if we split that
inode over the end of the log across log buffers, we need to also
another log op header, which takes us to 640 bytes. If there's
another reservation taken out of this that I haven't taken into
account (perhaps multiple iclog splits?) or I haven't corectly
calculated the bmbt format space used (entirely possible), then
we will overun it.

For v3 inodes the maximum is actually 724 bytes, and even a
single maximally sized btree format fork can blow it (652 bytes).
And that's exactly what is happening with the FSYNC_TS transaction
in the above output - it's consumed 644 bytes of space after the CIL
context took the space reserved for it (2100 bytes).

This problem has always been present in the XFS code - the btree
format inode forks have always been logged in this manner. Hence
there has always been the possibility of an overrun with such a
transaction. The CRC code has just exposed it frequently enough to
be able to debug and understand the root cause....

So, let's fix all the inode log space reservations.

[ I'm so glad we spent the effort to clean up the transaction
  reservation code. This is an easy fix now. ]
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

The call to xfs_inobt_get_rec() in xfs_dialloc_ag() passes 'j' as
the output status variable. The immediately following
XFS_WANT_CORRUPTED_GOTO() checks the value of 'i,' which is from
the previous lookup call and has already been checked. Fix the
corruption check to use 'j.'
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

CRC enabled filesystems fail log recovery with 100% reliability on
xfstests xfs/085 with the following failure:

XFS (vdb): Mounting Filesystem
XFS (vdb): Starting recovery (logdev: internal)
XFS (vdb): Corruption detected. Unmount and run xfs_repair
XFS (vdb): bad inode magic/vsn daddr 144 #0 (magic=0)
XFS: Assertion failed: 0, file: fs/xfs/xfs_inode_buf.c, line: 95

The problem is that the inode buffer has not been recovered before
the readahead on the inode buffer is issued. The checkpoint being
recovered actually allocates the inode chunk we are doing readahead
from, so what comes from disk during readahead is essentially
random and the verifier barfs on it.

This inode buffer readahead problem affects non-crc filesystems,
too, but xfstests does not trigger it at all on such
configurations....
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBen Myers <bpm@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Log recovery has some strict ordering requirements which unordered
or reordered metadata writeback can defeat. This can occur when an
item is logged in a transaction, written back to disk, and then
logged in a new transaction before the tail of the log is moved past
the original modification.

The result of this is that when we read an object off disk for
recovery purposes, the buffer that we read may not contain the
object type that recovery is expecting and hence at the end of the
checkpoint being recovered we have an invalid object in memory.

This isn't usually a problem, as recovery will then replay all the
other checkpoints and that brings the object back to a valid and
correct state, but the issue is that while the object is in the
invalid state it can be flushed to disk. This results in the object
verifier failing and triggering a corruption shutdown of log
recover. This is correct behaviour for the verifiers - the problem
is that we are not detecting that the object we've read off disk is
newer than the transaction we are replaying.

All metadata in v5 filesystems has the LSN of it's last modification
stamped in it. This enabled log recover to read that field and
determine the age of the object on disk correctly. If the LSN of the
object on disk is older than the transaction being replayed, then we
replay the modification. If the LSN of the object matches or is more
recent than the transaction's LSN, then we should avoid overwriting
the object as that is what leads to the transient corrupt state.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

When testing LSN ordering code for v5 superblocks, it was discovered
that the the LSN embedded in the generic btree blocks was
occasionally uninitialised. These values didn't get written to disk
by metadata writeback - they got written by previous transactions in
log recovery.

The issue is here that the when the block is first allocated and
initialised, the LSN field was not initialised - it gets overwritten
before IO is issued on the buffer - but the value that is logged by
transactions that modify the header before it is written to disk
(and initialised) contain garbage. Hence the first recovery of the
buffer will stamp garbage into the LSN field, and that can cause
subsequent transactions to not replay correctly.

The fix is simply to initialise the bb_lsn field to zero when we
initialise the block for the first time.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

XFS: Assertion failed: first <= last && last < BBTOB(bp->b_length), file: fs/xfs/xfs_trans_buf.c, line: 568

The calculation doesn't take into account the size of the dir v3
header, so overestimates the hash entries in a node. This causes
directory buffer overruns when splitting and merging nodes.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Tested-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

xfstests xfs/087 fails 100% reliably with this assert:

XFS (vdb): Mounting Filesystem
XFS (vdb): Starting recovery (logdev: internal)
XFS: Assertion failed: bp->b_flags & XBF_STALE, file: fs/xfs/xfs_buf.c, line: 548

while trying to read a dquot buffer in xlog_recover_dquot_ra_pass2().

The issue is that the buffer length to read that is passed to
xfs_buf_readahead is in units of filesystem blocks, not disk blocks.
(i.e. FSB, not daddr). Fix it but putting the correct conversion in
place.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBen Myers <bpm@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

When doing readhaead in log recovery, we check to see if buffers are
cancelled before doing readahead. If we find a cancelled buffer,
however, we always decrement the reference count we have on it, and
that means that readahead is causing a double decrement of the
cancelled buffer reference count.

This results in log recovery *replaying cancelled buffers* as the
actual recovery pass does not find the cancelled buffer entry in the
commit phase of the second pass across a transaction. On debug
kernels, this results in an ASSERT failure like so:

XFS: Assertion failed: !(flags & XFS_BLF_CANCEL), file: fs/xfs/xfs_log_recover.c, line: 1815

xfstests generic/311 reproduces this ASSERT failure with 100%
reproducability.

Fix it by making readahead only peek at the buffer cancelled state
rather than the full accounting that xlog_check_buffer_cancelled()
does.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBen Myers <bpm@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

The "di_size" variable comes from the disk and it's a signed 64 bit.
We check the upper limit but we should check for negative numbers as
well.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: NBen Myers <bpm@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

TO: Dave Chinner <david@fromorbit.com>
CC: Ben Myers <bpm@sgi.com>
CC: linux-kernel@vger.kernel.org 
Signed-off-by: NFengguang Wu <fengguang.wu@intel.com>
Reviewed-by: NBen Myers <bpm@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

  It can take a long time to run log recovery operation because it is
single threaded and is bound by read latency. We can find that it took
most of the time to wait for the read IO to occur, so if one object
readahead is introduced to log recovery, it will obviously reduce the
log recovery time.

Log recovery time stat:

          w/o this patch        w/ this patch

real:        0m15.023s             0m7.802s
user:        0m0.001s              0m0.001s
sys:         0m0.246s              0m0.107s
Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: NBen Myers <bpm@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

At xfs_ail_min(), we do check if the AIL list is empty or not before
returning the first item in it with list_empty() and list_first_entry().

This can be simplified a bit with a new list operation routine that is
the list_first_entry_or_null() which has been introduced by:

commit 6d7581e6
    list: introduce list_first_entry_or_null

v2: make xfs_ail_min() as a static inline function and move it to
    xfs_trans_priv.h as per Dave Chinner's comments.
Signed-off-by: NJie Liu <jeff.liu@oracle.com>
Reviewed-by: NBen Myers <bpm@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Currently the code initializizes mp->m_icsb_mutex and other things
_after_ register_hotcpu_notifier().
As the notifier takes mp->m_icsb_mutex it can happen
that it takes the lock before it's initialization.
Signed-off-by: NRichard Weinberger <richard@nod.at>
Reviewed-by: NBen Myers <bpm@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Add XFS superblock v4 support for the file type field in the
directory entry feature.

This support adds a feature bit for version 4 superblocks and
leaves the original superblock 5 incompatibility bit.
Signed-off-by: NMark Tinguely <tinguely@sgi.com>
Reviewed-by: NGeoffrey Wehrman <gwehrman@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Add support to propagate and add filetype values into the on-disk
directs. This involves passing the filetype into the xfs_da_args
structure along with the name and namelength for direct operations,
and encoding it into the dirent at the same time we write the inode
number into the dirent.

With write support, add the feature flag to the
XFS_SB_FEAT_INCOMPAT_ALL mask so we can now mount filesystems with
this feature set.

Performance of directory recursion is now much improved. Parallel
walk of ~50 million directory entries across hundreds of directories
improves significantly. Unpatched, no CRCs:

Walking via ls -R

real    3m19.886s
user    6m36.960s
sys     28m19.087s

THis is doing roughly 500 getdents() calls per second, and 250,000
inode lookups per second to determine the inode type at roughly
17,000 read IOPS. CPU usage is 90% kernel space.

With dtype support patched in and the fileset recreated with CRCs
enabled:

Walking via ls -R

real    0m31.316s
user    6m32.975s
sys     0m21.111s

This is doing roughly 3500 getdents() calls per second at 16,000
IOPS. There are no inode lookups at all. CPU usages is almost 100%
userspace.

This is a big win for recursive directory walks that only need to
find file names and file types.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Add support for the file type field in directory entries so that
readdir can return the type of the inode the dirent points to to
userspace without first having to read the inode off disk.

The encoding of the type field is a single byte that is added to the
end of the directory entry name length. For all intents and
purposes, it appends a "hidden" byte to the name field which
contains the type information. As the directory entry is already of
dynamic size, helpers are already required to access and decode the
direct entry structures.

Hence the relevent extraction and iteration helpers are updated to
understand the hidden byte.  Helpers for reading and writing the
filetype field from the directory entries are also added. Only the
read helpers are used by this patch.  It also adds all the code
necessary to read the type information out of the dirents on disk.

Further we add the superblock feature bit and helpers to indicate
that we understand the on-disk format change. This is not a
compatible change - existing kernels cannot read the new format
successfully - so an incompatible feature flag is added. We don't
yet allow filesystems to mount with this flag yet - that will be
added once write support is added.

Finally, the code to take the type from the VFS, convert it to an
XFS on-disk type and put it into the xfs_name structures passed
around is added, but the directory code does not use this field yet.
That will be in the next patch.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Acked-by: NJeremy Kerr <jk@ozlabs.org>
Tested-by: NJeremy Kerr <jk@ozlabs.org>
Signed-off-by: NDwight Engen <dwight.engen@oracle.com>
Reviewed-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NBen Myers <bpm@sgi.com>

For XFS, add support for Q_XGETQSTATV quotactl command.
Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
Reviewed-by: NRich Johnston <rjohnston@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

XFS now supports three types of quotas (user, group and project).

Current version of Q_XGETSTAT has support for only two types of quotas.
In order to support three types of quotas, the interface, specifically
struct fs_quota_stat, need to be expanded. Current version of fs_quota_stat
does not allow expansion without breaking backward compatibility.

So, a quotactl command and new fs_quota_stat structure need to be added.

This patch adds a new command Q_XGETQSTATV to quotactl() which takes
a new data structure fs_quota_statv. This new data structure provides
support for future expansion and backward compatibility.

Callers of the new quotactl command have to set the version of the data
structure being passed, and kernel will fill as much data as requested.
If the kernel does not support the user-space provided version, EINVAL
will be returned. User-space can reduce the version number and call the same
quotactl again.
Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
Reviewed-by: NJan Kara <jack@suse.cz>
Reviewed-by: NRich Johnston <rjohnston@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

[v2: Applied rjohnston's suggestions as per Chandra's request. -bpm]

Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Follow up with xfs naming style.
Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>