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2684 Commits

Author SHA1 Message Date
Dave Chinner
e400d27d16 xfs: fix dir3 freespace block corruption
When the directory freespace index grows to a second block (2017
4k data blocks in the directory), the initialisation of the second
new block header goes wrong. The write verifier fires a corruption
error indicating that the block number in the header is zero. This
was being tripped by xfs/110.

The problem is that the initialisation of the new block is done just
fine in xfs_dir3_free_get_buf(), but the caller then users a dirv2
structure to zero on-disk header fields that xfs_dir3_free_get_buf()
has already zeroed. These lined up with the block number in the dir
v3 header format.

While looking at this, I noticed that the struct xfs_dir3_free_hdr()
had 4 bytes of padding in it that wasn't defined as padding or being
zeroed by the initialisation. Add a pad field declaration and fully
zero the on disk and in-core headers in xfs_dir3_free_get_buf() so
that this is never an issue in the future. Note that this doesn't
change the on-disk layout, just makes the 32 bits of padding in the
layout explicit.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

(cherry picked from commit 5ae6e6a401)
2013-05-30 17:22:54 -05:00
Dave Chinner
7c9950fd2a xfs: disable swap extents ioctl on CRC enabled filesystems
Currently, swapping extents from one inode to another is a simple
act of switching data and attribute forks from one inode to another.
This, unfortunately in no longer so simple with CRC enabled
filesystems as there is owner information embedded into the BMBT
blocks that are swapped between inodes. Hence swapping the forks
between inodes results in the inodes having mapping blocks that
point to the wrong owner and hence are considered corrupt.

To fix this we need an extent tree block or record based swap
algorithm so that the BMBT block owner information can be updated
atomically in the swap transaction. This is a significant piece of
new work, so for the moment simply don't allow swap extent
operations to succeed on CRC enabled filesystems.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

(cherry picked from commit 02f75405a7)
2013-05-30 17:20:08 -05:00
Dave Chinner
e7927e879d xfs: add fsgeom flag for v5 superblock support.
Currently userspace has no way of determining that a filesystem is
CRC enabled. Add a flag to the XFS_IOC_FSGEOMETRY ioctl output to
indicate that the filesystem has v5 superblock support enabled.
This will allow xfs_info to correctly report the state of the
filesystem.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

(cherry picked from commit 74137fff06)
2013-05-30 17:19:45 -05:00
Dave Chinner
1de09d1ae4 xfs: fix incorrect remote symlink block count
When CRCs are enabled, the number of blocks needed to hold a remote
symlink on a 1k block size filesystem may be 2 instead of 1. The
transaction reservation for the allocated blocks was not taking this
into account and only allocating one block. Hence when trying to
read or invalidate such symlinks, we are mapping a hole where there
should be a block and things go bad at that point.

Fix the reservation to use the correct block count, clean up the
block count calculation similar to the remote attribute calculation,
and add a debug guard to detect when we don't write the entire
symlink to disk.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

(cherry picked from commit 321a95839e)
2013-05-30 17:19:07 -05:00
Dave Chinner
7d2ffe80aa xfs: fix split buffer vector log recovery support
A long time ago in a galaxy far away....

.. the was a commit made to fix some ilinux specific "fragmented
buffer" log recovery problem:

http://oss.sgi.com/cgi-bin/gitweb.cgi?p=archive/xfs-import.git;a=commitdiff;h=b29c0bece51da72fb3ff3b61391a391ea54e1603

That problem occurred when a contiguous dirty region of a buffer was
split across across two pages of an unmapped buffer. It's been a
long time since that has been done in XFS, and the changes to log
the entire inode buffers for CRC enabled filesystems has
re-introduced that corner case.

And, of course, it turns out that the above commit didn't actually
fix anything - it just ensured that log recovery is guaranteed to
fail when this situation occurs. And now for the gory details.

xfstest xfs/085 is failing with this assert:

XFS (vdb): bad number of regions (0) in inode log format
XFS: Assertion failed: 0, file: fs/xfs/xfs_log_recover.c, line: 1583

Largely undocumented factoid #1: Log recovery depends on all log
buffer format items starting with this format:

struct foo_log_format {
	__uint16_t	type;
	__uint16_t	size;
	....

As recoery uses the size field and assumptions about 32 bit
alignment in decoding format items.  So don't pay much attention to
the fact log recovery thinks that it decoding an inode log format
item - it just uses them to determine what the size of the item is.

But why would it see a log format item with a zero size? Well,
luckily enough xfs_logprint uses the same code and gives the same
error, so with a bit of gdb magic, it turns out that it isn't a log
format that is being decoded. What logprint tells us is this:

Oper (130): tid: a0375e1a  len: 28  clientid: TRANS  flags: none
BUF:  #regs: 2   start blkno: 144 (0x90)  len: 16  bmap size: 2  flags: 0x4000
Oper (131): tid: a0375e1a  len: 4096  clientid: TRANS  flags: none
BUF DATA
----------------------------------------------------------------------------
Oper (132): tid: a0375e1a  len: 4096  clientid: TRANS  flags: none
xfs_logprint: unknown log operation type (4e49)
**********************************************************************
* ERROR: data block=2                                                 *
**********************************************************************

That we've got a buffer format item (oper 130) that has two regions;
the format item itself and one dirty region. The subsequent region
after the buffer format item and it's data is them what we are
tripping over, and the first bytes of it at an inode magic number.
Not a log opheader like there is supposed to be.

That means there's a problem with the buffer format item. It's dirty
data region is 4096 bytes, and it contains - you guessed it -
initialised inodes. But inode buffers are 8k, not 4k, and we log
them in their entirety. So something is wrong here. The buffer
format item contains:

(gdb) p /x *(struct xfs_buf_log_format *)in_f
$22 = {blf_type = 0x123c, blf_size = 0x2, blf_flags = 0x4000,
       blf_len = 0x10, blf_blkno = 0x90, blf_map_size = 0x2,
       blf_data_map = {0xffffffff, 0xffffffff, .... }}

Two regions, and a signle dirty contiguous region of 64 bits.  64 *
128 = 8k, so this should be followed by a single 8k region of data.
And the blf_flags tell us that the type of buffer is a
XFS_BLFT_DINO_BUF. It contains inodes. And because it doesn't have
the XFS_BLF_INODE_BUF flag set, that means it's an inode allocation
buffer. So, it should be followed by 8k of inode data.

But we know that the next region has a header of:

(gdb) p /x *ohead
$25 = {oh_tid = 0x1a5e37a0, oh_len = 0x100000, oh_clientid = 0x69,
       oh_flags = 0x0, oh_res2 = 0x0}

and so be32_to_cpu(oh_len) = 0x1000 = 4096 bytes. It's simply not
long enough to hold all the logged data. There must be another
region. There is - there's a following opheader for another 4k of
data that contains the other half of the inode cluster data - the
one we assert fail on because it's not a log format header.

So why is the second part of the data not being accounted to the
correct buffer log format structure? It took a little more work with
gdb to work out that the buffer log format structure was both
expecting it to be there but hadn't accounted for it. It was at that
point I went to the kernel code, as clearly this wasn't a bug in
xfs_logprint and the kernel was writing bad stuff to the log.

First port of call was the buffer item formatting code, and the
discontiguous memory/contiguous dirty region handling code
immediately stood out. I've wondered for a long time why the code
had this comment in it:

                        vecp->i_addr = xfs_buf_offset(bp, buffer_offset);
                        vecp->i_len = nbits * XFS_BLF_CHUNK;
                        vecp->i_type = XLOG_REG_TYPE_BCHUNK;
/*
 * You would think we need to bump the nvecs here too, but we do not
 * this number is used by recovery, and it gets confused by the boundary
 * split here
 *                      nvecs++;
 */
                        vecp++;

And it didn't account for the extra vector pointer. The case being
handled here is that a contiguous dirty region lies across a
boundary that cannot be memcpy()d across, and so has to be split
into two separate operations for xlog_write() to perform.

What this code assumes is that what is written to the log is two
consecutive blocks of data that are accounted in the buf log format
item as the same contiguous dirty region and so will get decoded as
such by the log recovery code.

The thing is, xlog_write() knows nothing about this, and so just
does it's normal thing of adding an opheader for each vector. That
means the 8k region gets written to the log as two separate regions
of 4k each, but because nvecs has not been incremented, the buf log
format item accounts for only one of them.

Hence when we come to log recovery, we process the first 4k region
and then expect to come across a new item that starts with a log
format structure of some kind that tells us whenteh next data is
going to be. Instead, we hit raw buffer data and things go bad real
quick.

So, the commit from 2002 that commented out nvecs++ is just plain
wrong. It breaks log recovery completely, and it would seem the only
reason this hasn't been since then is that we don't log large
contigous regions of multi-page unmapped buffers very often. Never
would be a closer estimate, at least until the CRC code came along....

So, lets fix that by restoring the nvecs accounting for the extra
region when we hit this case.....

.... and there's the problemin log recovery it is apparently working
around:

XFS: Assertion failed: i == item->ri_total, file: fs/xfs/xfs_log_recover.c, line: 2135

Yup, xlog_recover_do_reg_buffer() doesn't handle contigous dirty
regions being broken up into multiple regions by the log formatting
code. That's an easy fix, though - if the number of contiguous dirty
bits exceeds the length of the region being copied out of the log,
only account for the number of dirty bits that region covers, and
then loop again and copy more from the next region. It's a 2 line
fix.

Now xfstests xfs/085 passes, we have one less piece of mystery
code, and one more important piece of knowledge about how to
structure new log format items..

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

(cherry picked from commit 709da6a61a)
2013-05-30 17:18:01 -05:00
Dave Chinner
2962f5a5dc xfs: kill suid/sgid through the truncate path.
XFS has failed to kill suid/sgid bits correctly when truncating
files of non-zero size since commit c4ed4243 ("xfs: split
xfs_setattr") introduced in the 3.1 kernel. Fix it.

Fix it.

cc: stable kernel <stable@vger.kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

(cherry picked from commit 56c19e89b3)
2013-05-30 17:17:35 -05:00
Dave Chinner
08fb39051f xfs: avoid nesting transactions in xfs_qm_scall_setqlim()
Lockdep reports:

=============================================
[ INFO: possible recursive locking detected ]
3.9.0+ #3 Not tainted
---------------------------------------------
setquota/28368 is trying to acquire lock:
 (sb_internal){++++.?}, at: [<c11e8846>] xfs_trans_alloc+0x26/0x50

but task is already holding lock:
 (sb_internal){++++.?}, at: [<c11e8846>] xfs_trans_alloc+0x26/0x50

from xfs_qm_scall_setqlim()->xfs_dqread() when a dquot needs to be
allocated.

xfs_qm_scall_setqlim() is starting a transaction and then not
passing it into xfs_qm_dqet() and so it starts it's own transaction
when allocating the dquot.  Splat!

Fix this by not allocating the dquot in xfs_qm_scall_setqlim()
inside the setqlim transaction. This requires getting the dquot
first (and allocating it if necessary) then dropping and relocking
the dquot before joining it to the setqlim transaction.

Reported-by: Michael L. Semon <mlsemon35@gmail.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
(cherry picked from commit f648167f3a)
2013-05-30 17:10:56 -05:00
Dave Chinner
7ae077802c xfs: remote attribute lookups require the value length
When reading a remote attribute, to correctly calculate the length
of the data buffer for CRC enable filesystems, we need to know the
length of the attribute data. We get this information when we look
up the attribute, but we don't store it in the args structure along
with the other remote attr information we get from the lookup. Add
this information to the args structure so we can use it
appropriately.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

(cherry picked from commit e461fcb194)
2013-05-24 16:31:20 -05:00
Dave Chinner
cf257abf02 xfs: xfs_attr_shortform_allfit() does not handle attr3 format.
xfstests generic/117 fails with:

XFS: Assertion failed: leaf->hdr.info.magic == cpu_to_be16(XFS_ATTR_LEAF_MAGIC)

indicating a function that does not handle the attr3 format
correctly. Fix it.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
(cherry picked from commit b38958d715)
2013-05-24 16:29:56 -05:00
Dave Chinner
7ced60cae4 xfs: xfs_da3_node_read_verify() doesn't handle XFS_ATTR3_LEAF_MAGIC
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

(cherry picked from commit 72916fb8cb)
2013-05-24 16:29:37 -05:00
Dave Chinner
b17cb364db xfs: fix missing KM_NOFS tags to keep lockdep happy
There are several places where we use KM_SLEEP allocation contexts
and use the fact that they are called from transaction context to
add KM_NOFS where appropriate. Unfortunately, there are several
places where the code makes this assumption but can be called from
outside transaction context but with filesystem locks held. These
places need explicit KM_NOFS annotations to avoid lockdep
complaining about reclaim contexts.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

(cherry picked from commit ac14876cf9)
2013-05-24 16:29:15 -05:00
Dave Chinner
509e708a89 xfs: Don't reference the EFI after it is freed
Checking the EFI for whether it is being released from recovery
after we've already released the known active reference is a mistake
worthy of a brown paper bag. Fix the (now) obvious use after free
that it can cause.

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

(cherry picked from commit 52c24ad39f)
2013-05-24 16:27:57 -05:00
Dave Chinner
7031d0e1c4 xfs: fix rounding in xfs_free_file_space
The offset passed into xfs_free_file_space() needs to be rounded
down to a certain size, but the rounding mask is built by a 32 bit
variable. Hence the mask will always mask off the upper 32 bits of
the offset and lead to incorrect writeback and invalidation ranges.

This is not actually exposed as a bug because we writeback and
invalidate from the rounded offset to the end of the file, and hence
the offset we are actually punching a hole out of will always be
covered by the code. This needs fixing, however, if we ever want to
use exact ranges for writeback/invalidation here...

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

(cherry picked from commit 28ca489c63)
2013-05-24 16:27:41 -05:00
Dave Chinner
480d7467e4 xfs: fix sub-page blocksize data integrity writes
FSX on 512 byte block size filesystems has been failing for some
time with corrupted data. The fault dates back to the change in
the writeback data integrity algorithm that uses a mark-and-sweep
approach to avoid data writeback livelocks.

Unfortunately, a side effect of this mark-and-sweep approach is that
each page will only be written once for a data integrity sync, and
there is a condition in writeback in XFS where a page may require
two writeback attempts to be fully written. As a result of the high
level change, we now only get a partial page writeback during the
integrity sync because the first pass through writeback clears the
mark left on the page index to tell writeback that the page needs
writeback....

The cause is writing a partial page in the clustering code. This can
happen when a mapping boundary falls in the middle of a page - we
end up writing back the first part of the page that the mapping
covers, but then never revisit the page to have the remainder mapped
and written.

The fix is simple - if the mapping boundary falls inside a page,
then simple abort clustering without touching the page. This means
that the next ->writepage entry that write_cache_pages() will make
is the page we aborted on, and xfs_vm_writepage() will map all
sections of the page correctly. This behaviour is also optimal for
non-data integrity writes, as it results in contiguous sequential
writeback of the file rather than missing small holes and having to
write them a "random" writes in a future pass.

With this fix, all the fsx tests in xfstests now pass on a 512 byte
block size filesystem on a 4k page machine.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

(cherry picked from commit 49b137cbbc)
2013-05-24 16:26:51 -05:00
Linus Torvalds
8769e078a9 xfs: update (#2) for v3.10-rc1
* add CONFIG_XFS_WARN, a step between zero debugging and CONFIG_XFS_DEBUG.
 * fix attrmulti and attrlist to fall back to vmalloc when kmalloc fails.
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Merge tag 'for-linus-v3.10-rc1-2' of git://oss.sgi.com/xfs/xfs

Pull xfs update (#2) from Ben Myers:

 - add CONFIG_XFS_WARN, a step between zero debugging and
   CONFIG_XFS_DEBUG.

 - fix attrmulti and attrlist to fall back to vmalloc when kmalloc
   fails.

* tag 'for-linus-v3.10-rc1-2' of git://oss.sgi.com/xfs/xfs:
  xfs: fallback to vmalloc for large buffers in xfs_compat_attrlist_by_handle
  xfs: fallback to vmalloc for large buffers in xfs_attrlist_by_handle
  xfs: introduce CONFIG_XFS_WARN
2013-05-09 13:06:20 -07:00
Kent Overstreet
a27bb332c0 aio: don't include aio.h in sched.h
Faster kernel compiles by way of fewer unnecessary includes.

[akpm@linux-foundation.org: fix fallout]
[akpm@linux-foundation.org: fix build]
Signed-off-by: Kent Overstreet <koverstreet@google.com>
Cc: Zach Brown <zab@redhat.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Reviewed-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 20:16:25 -07:00
Eric Sandeen
7dfbcbefad xfs: fallback to vmalloc for large buffers in xfs_compat_attrlist_by_handle
Shamelessly copied from dchinner's:
ad650f5b xfs: fallback to vmalloc for large buffers in xfs_attrmulti_attr_get
    
xfsdump uses a large buffer for extended attributes, which has a
kmalloc'd shadow buffer in the kernel. This can fail after the
system has been running for some time as it is a high order
allocation. Add a fallback to vmalloc so that it doesn't require
contiguous memory and so won't randomly fail while xfsdump is
running.

This was done for xfs_attrlist_by_handle but
xfs_compat_attrlist_by_handle (the 32-bit version) needs the same
attention.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-05-07 19:00:10 -05:00
Eric Sandeen
dd700d9452 xfs: fallback to vmalloc for large buffers in xfs_attrlist_by_handle
Shamelessly copied from dchinner's:
ad650f5b xfs: fallback to vmalloc for large buffers in xfs_attrmulti_attr_get
    
xfsdump uses for a large buffer for extended attributes, which has a
kmalloc'd shadow buffer in the kernel. This can fail after the
system has been running for some time as it is a high order
allocation. Add a fallback to vmalloc so that it doesn't require
contiguous memory and so won't randomly fail while xfsdump is
running.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-05-07 18:56:38 -05:00
Dave Chinner
742ae1e35b xfs: introduce CONFIG_XFS_WARN
Running a CONFIG_XFS_DEBUG kernel in production environments is not
the best idea as it introduces significant overhead, can change
the behaviour of algorithms (such as allocation) to improve test
coverage, and (most importantly) panic the machine on non-fatal
errors.

There are many cases where all we want to do is run a
kernel with more bounds checking enabled, such as is provided by the
ASSERT() statements throughout the code, but without all the
potential overhead and drawbacks.

This patch converts all the ASSERT statements to evaluate as
WARN_ON(1) statements and hence if they fail dump a warning and a
stack trace to the log. This has minimal overhead and does not
change any algorithms, and will allow us to find strange "out of
bounds" problems more easily on production machines.

There are a few places where assert statements contain debug only
code. These are converted to be debug-or-warn only code so that we
still get all the assert checks in the code.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-05-07 18:45:36 -05:00
Linus Torvalds
c8d8566952 xfs: update for v3.10-rc1
For 3.10-rc1 we have a number of bug fixes and cleanups and a currently
 experimental feature from David Chinner, CRCs protection for metadata.
 CRCs are enabled by using mkfs.xfs to create a filesystem with the
 feature bits set.
 
 * numerous fixes for speculative preallocation
 * don't verify buffers on IO errors
 * rename of random32 to prandom32
 * refactoring/rearrangement in xfs_bmap.c
 * removal of unused m_inode_shrink in struct xfs_mount
 * fix error handling of xfs_bufs and readahead
 * quota driven preallocation throttling
 * fix WARN_ON in xfs_vm_releasepage
 * add ratelimited printk for different alert levels
 * fix spurious forced shutdowns due to freed Extent Free Intents
 * remove some obsolete XLOG_CIL_HARD_SPACE_LIMIT() macros
 * remove some obsoleted comments
 * (experimental) CRC support for metadata
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Merge tag 'for-linus-v3.10-rc1' of git://oss.sgi.com/xfs/xfs

Pull xfs update from Ben Myers:
 "For 3.10-rc1 we have a number of bug fixes and cleanups and a
  currently experimental feature from David Chinner, CRCs protection for
  metadata.  CRCs are enabled by using mkfs.xfs to create a filesystem
  with the feature bits set.

   - numerous fixes for speculative preallocation
   - don't verify buffers on IO errors
   - rename of random32 to prandom32
   - refactoring/rearrangement in xfs_bmap.c
   - removal of unused m_inode_shrink in struct xfs_mount
   - fix error handling of xfs_bufs and readahead
   - quota driven preallocation throttling
   - fix WARN_ON in xfs_vm_releasepage
   - add ratelimited printk for different alert levels
   - fix spurious forced shutdowns due to freed Extent Free Intents
   - remove some obsolete XLOG_CIL_HARD_SPACE_LIMIT() macros
   - remove some obsoleted comments
   - (experimental) CRC support for metadata"

* tag 'for-linus-v3.10-rc1' of git://oss.sgi.com/xfs/xfs: (46 commits)
  xfs: fix da node magic number mismatches
  xfs: Remote attr validation fixes and optimisations
  xfs: Teach dquot recovery about CONFIG_XFS_QUOTA
  xfs: add metadata CRC documentation
  xfs: implement extended feature masks
  xfs: add CRC checks to the superblock
  xfs: buffer type overruns blf_flags field
  xfs: add buffer types to directory and attribute buffers
  xfs: add CRC protection to remote attributes
  xfs: split remote attribute code out
  xfs: add CRCs to attr leaf blocks
  xfs: add CRCs to dir2/da node blocks
  xfs: shortform directory offsets change for dir3 format
  xfs: add CRC checking to dir2 leaf blocks
  xfs: add CRC checking to dir2 data blocks
  xfs: add CRC checking to dir2 free blocks
  xfs: add CRC checks to block format directory blocks
  xfs: add CRC checks to remote symlinks
  xfs: split out symlink code into it's own file.
  xfs: add version 3 inode format with CRCs
  ...
2013-05-02 14:49:33 -07:00
Dave Chinner
cab09a81fb xfs: fix da node magic number mismatches
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-05-01 14:48:30 -05:00
Dave Chinner
946217ba28 xfs: Remote attr validation fixes and optimisations
- optimise the calcuation for the number of blocks in a remote
  xattr.
- check attribute length against MAX_XATTR_SIZE, not MAXPATHLEN
- whitespace fixes

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-05-01 14:13:55 -05:00
Dave Chinner
123887e843 xfs: Teach dquot recovery about CONFIG_XFS_QUOTA
Fix a build error when CONFIG_XFS_QUOTA=n:

fs/built-in.o: In function `xlog_recovery_validate_buf_type':
/home/dave/src/build/x86-64/xfsdev/fs/xfs/xfs_log_recover.c:1948: undefined
reference to `xfs_dquot_buf_ops'

Reported-by: Michael L. Semon <mlsemon35@gmail.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-30 13:07:37 -05:00
Dave Chinner
e721f504cf xfs: implement extended feature masks
The version 5 superblock has extended feature masks for compatible,
incompatible and read-only compatible feature sets. Implement the
masking and mount-time checking for these feature masks.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-27 13:05:18 -05:00
Dave Chinner
04a1e6c5b2 xfs: add CRC checks to the superblock
With the addition of CRCs, there is such a wide and varied change to
the on disk format that it makes sense to bump the superblock
version number rather than try to use feature bits for all the new
functionality.

This commit introduces all the new superblock fields needed for all
the new functionality: feature masks similar to ext4, separate
project quota inodes, a LSN field for recovery and the CRC field.

This commit does not bump the superblock version number, however.
That will be done as a separate commit at the end of the series
after all the new functionality is present so we switch it all on in
one commit. This means that we can slowly introduce the changes
without them being active and hence maintain bisectability of the
tree.

This patch is based on a patch originally written by myself back
from SGI days, which was subsequently modified by Christoph Hellwig.
There is relatively little of that patch remaining, but the history
of the patch still should be acknowledged here.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-27 13:03:12 -05:00
Dave Chinner
61fe135c1d xfs: buffer type overruns blf_flags field
The buffer type passed to log recvoery in the buffer log item
overruns the blf_flags field. I had assumed that flags field was a
32 bit value, and it turns out it is a unisgned short. Therefore
having 19 flags doesn't really work.

Convert the buffer type field to numeric value, and use the top 5
bits of the flags field for it. We currently have 17 types of
buffers, so using 5 bits gives us plenty of room for expansion in
future....

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-27 13:01:58 -05:00
Dave Chinner
d75afeb3d3 xfs: add buffer types to directory and attribute buffers
Add buffer types to the buffer log items so that log recovery can
validate the buffers and calculate CRCs correctly after the buffers
are recovered.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-27 13:01:06 -05:00
Dave Chinner
d2e448d5fd xfs: add CRC protection to remote attributes
There are two ways of doing this - the first is to add a CRC to the
remote attribute entry in the attribute block. The second is to
treat them similar to the remote symlink, where each fragment has
it's own header and identifies fragment location in the attribute.

The problem with the CRC in the remote attr entry is that we cannot
identify the owner of the metadata from the metadata blocks
themselves, or where the blocks fit into the remote attribute. The
down side to this approach is that we never know when the attribute
has been read from disk or not and so we have to verify it every
time it is read, and we must calculate it during the create
transaction and log it. We do not log CRCs for any other metadata,
and so this creates a unique set of coherency problems that, in
general, are best avoided.

Adding an identifying header to each allocated block allows us to
identify each fragment and where in the attribute it is located. It
enables us to rebuild the remote attribute from just the raw blocks
containing the attribute. It also provides us to do per-block CRCs
verification at IO time rather than during the transaction context
that creates it or every time it is read into a user buffer. Hence
it avoids all the problems that an external, logged CRC has, and
provides all the benefits of self identifying metadata.

The only complexity is that we have to add a header per fragment,
and we don't know how many fragments will be needed prior to
allocations. If we take the symlink example, the header is 56 bytes
and hence for a 4k block size filesystem, in the worst case 16
headers requires 1 extra block for the 64k attribute data. For 512
byte filesystems the worst case is an extra block for every 9
fragments (i.e. 16 extra blocks in the worse case). This will be
very rare and so it's not really a major concern.

Because allocation is done in two steps - the first finds a hole
large enough in the attribute file, the second does the allocation -
we only need to find a hole big enough for a worst case allocation.
We only need to allocate enough extra blocks for number of headers
required by the fragments, and we can calculate that as we go....

Hence it really only makes sense to use the same model as for
symlinks - it doesn't add that much complexity, does not require an
attribute tree format change, and does not require logging
calculated CRC values.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-27 12:58:53 -05:00
Dave Chinner
95920cd6ce xfs: split remote attribute code out
Adding CRC support to remote attributes adds a significant amount of
remote attribute specific code. Split the existing remote attribute
code out into it's own file so that all the relevant remote
attribute code is in a single, easy to find place.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-27 12:49:32 -05:00
Dave Chinner
517c22207b xfs: add CRCs to attr leaf blocks
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-27 12:45:01 -05:00
Dave Chinner
f5ea110044 xfs: add CRCs to dir2/da node blocks
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-27 12:33:38 -05:00
Dave Chinner
6b2647a12a xfs: shortform directory offsets change for dir3 format
Because the header size for the CRC enabled directory blocks is
larger, the offset of the first entry into a directory block is
different to the dir2 format. The shortform directory stores the
dirent's offset so that it doesn't change when moving from shortform
to block form and back again, and hence it needs to take into
account the different header sizes to maintain the correct offsets.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-27 12:24:32 -05:00
Dave Chinner
24df33b45e xfs: add CRC checking to dir2 leaf blocks
This addition follows the same pattern as the dir2 block CRCs.
Seeing as both LEAF1 and LEAFN types need to changed at the same
time, this is a pretty large amount of change. leaf block headers
need to be abstracted away from the on-disk structures (struct
xfs_dir3_icleaf_hdr), as do the base leaf entry locations.

This header abstract allows the in-core header and leaf entry
location to be passed around instead of the leaf block itself. This
saves a lot of converting individual variables from on-disk format
to host format where they are used, so there's a good chance that
the compiler will be able to produce much more optimal code as it's
not having to byteswap variables all over the place.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-27 12:19:53 -05:00
Dave Chinner
33363feed1 xfs: add CRC checking to dir2 data blocks
This addition follows the same pattern as the dir2 block CRCs.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-27 12:00:00 -05:00
Dave Chinner
cbc8adf897 xfs: add CRC checking to dir2 free blocks
This addition follows the same pattern as the dir2 block CRCs, but
with a few differences. The main difference is that the free block
header is different between the v2 and v3 formats, so an "in-core"
free block header has been added and _todisk/_from_disk functions
used to abstract the differences in structure format from the code.
This is similar to the on-disk superblock versus the in-core
superblock setup. The in-core strucutre is populated when the buffer
is read from disk, all the in memory checks and modifications are
done on the in-core version of the structure which is written back
to the buffer before the buffer is logged.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-27 11:58:16 -05:00
Dave Chinner
f5f3d9b016 xfs: add CRC checks to block format directory blocks
Now that directory buffers are made from a single struct xfs_buf, we
can add CRC calculation and checking callbacks. While there, add all
the fields to the on disk structures for future functionality such
as d_type support, uuids, block numbers, owner inode, etc.

To distinguish between the different on disk formats, change the
magic numbers for the new format directory blocks.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-27 11:51:56 -05:00
Dave Chinner
f948dd76dd xfs: add CRC checks to remote symlinks
Add a header to the remote symlink block, containing location and
owner information, as well as CRCs and LSN fields. This requires
verifiers to be added to the remote symlink buffers for CRC enabled
filesystems.

This also fixes a bug reading multiple block symlinks, where the second
block overwrites the first block when copying out the link name.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-27 11:49:28 -05:00
Dave Chinner
19de7351a8 xfs: split out symlink code into it's own file.
The symlink code is about to get more complicated when CRCs are
added for remote symlink blocks. The symlink management code is
mostly self contained, so move it to it's own files so that all the
new code and the existing symlink code will not be intermingled
with other unrelated code.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-21 15:38:04 -05:00
Christoph Hellwig
93848a999c xfs: add version 3 inode format with CRCs
Add a new inode version with a larger core.  The primary objective is
to allow for a crc of the inode, and location information (uuid and ino)
to verify it was written in the right place.  We also extend it by:

	a creation time (for Samba);
	a changecount (for NFSv4);
	a flush sequence (in LSN format for recovery);
	an additional inode flags field; and
	some additional padding.

These additional fields are not implemented yet, but already laid
out in the structure.

[dchinner@redhat.com] Added LSN and flags field, some factoring and rework to
capture all the necessary information in the crc calculation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-21 15:03:33 -05:00
Christoph Hellwig
3fe58f30b4 xfs: add CRC checks for quota blocks
Use the reserved space in struct xfs_dqblk to store a UUID and a crc
for the quota blocks.

[dchinner@redhat.com] Add a LSN field and update for current verifier
infrastructure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-21 14:58:22 -05:00
Dave Chinner
983d09ffe3 xfs: add CRC checks to the AGI
Same set of changes made to the AGF need to be made to the AGI.
This patch has a similar history to the AGF, hence a similar
sign-off chain.

Signed-off-by: Dave Chinner <dgc@sgi.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dgc@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-21 14:57:43 -05:00
Christoph Hellwig
77c95bba01 xfs: add CRC checks to the AGFL
Add CRC checks, location information and a magic number to the AGFL.
Previously the AGFL was just a block containing nothing but the
free block pointers.  The new AGFL has a real header with the usual
boilerplate instead, so that we can verify it's not corrupted and
written into the right place.

[dchinner@redhat.com] Added LSN field, reworked significantly to fit
into new verifier structure and growfs structure, enabled full
verifier functionality now there is a header to verify and we can
guarantee an initialised AGFL.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-21 14:55:34 -05:00
Dave Chinner
4e0e6040c4 xfs: add CRC checks to the AGF
The AGF already has some self identifying fields (e.g. the sequence
number) so we only need to add the uuid to it to identify the
filesystem it belongs to. The location is fixed based on the
sequence number, so there's no need to add a block number, either.

Hence the only additional fields are the CRC and LSN fields. These
are unlogged, so place some space between the end of the logged
fields and them so that future expansion of the AGF for logged
fields can be placed adjacent to the existing logged fields and
hence not complicate the field-derived range based logging we
currently have.

Based originally on a patch from myself, modified further by
Christoph Hellwig and then modified again to fit into the
verifier structure with additional fields by myself. The multiple
signed-off-by tags indicate the age and history of this patch.

Signed-off-by: Dave Chinner <dgc@sgi.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-21 14:54:46 -05:00
Christoph Hellwig
ee1a47ab0e xfs: add support for large btree blocks
Add support for larger btree blocks that contains a CRC32C checksum,
a filesystem uuid and block number for detecting filesystem
consistency and out of place writes.

[dchinner@redhat.com] Also include an owner field to allow reverse
mappings to be implemented for improved repairability and a LSN
field to so that log recovery can easily determine the last
modification that made it to disk for each buffer.

[dchinner@redhat.com] Add buffer log format flags to indicate the
type of buffer to recovery so that we don't have to do blind magic
number tests to determine what the buffer is.

[dchinner@redhat.com] Modified to fit into the verifier structure.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-21 14:53:46 -05:00
Dave Chinner
a2050646f6 xfs: increase hexdump output in xfs_corruption_error
Currently xfs_corruption_error() dumps the first 16 bytes of the
buffer that is passed to it when a corruption occurs. This is not
large enough to see the entire state of the header of the block that
was determined to be corrupt.  increase the output to 64 bytes to
capture the majority of all headers in all types of metadata blocks.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-21 14:48:41 -05:00
Jeff Liu
7fe3258c50 xfs: Update xfs_log_commit_cil() comments
xfs_log_commit_iclog() function has been removed by commits 93b8a585:
	xfs: remove the deprecated nodelaylog option

Beginning from Linux 3.3, only delayed logging is supported so that
we call xfs_log_commit_cil() at xfs_trans_commit() only, remove the
useless comments so.

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-16 13:20:03 -05:00
Jeff Liu
d4fd0e92fb xfs: Remove the obsolete XLOG_CIL_HARD_SPACE_LIMIT() macros
There is no more users of this Macro, so it's time to kill it dead.

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-16 13:18:33 -05:00
Al Viro
8d71db4f08 lift sb_start_write/sb_end_write out of ->aio_write()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-04-09 14:12:55 -04:00
Dave Chinner
666d644cd7 xfs: don't free EFIs before the EFDs are committed
Filesystems are occasionally being shut down with this error:

xfs_trans_ail_delete_bulk: attempting to delete a log item that is
not in the AIL.

It was diagnosed to be related to the EFI/EFD commit order when the
EFI and EFD are in different checkpoints and the EFD is committed
before the EFI here:

http://oss.sgi.com/archives/xfs/2013-01/msg00082.html

The real problem is that a single bit cannot fully describe the
states that the EFI/EFD processing can be in. These completion
states are:

EFI			EFI in AIL	EFD		Result
committed/unpinned	Yes		committed	OK
committed/pinned	No		committed	Shutdown
uncommitted		No		committed	Shutdown


Note that the "result" field is what should happen, not what does
happen. The current logic is broken and handles the first two cases
correctly by luck.  That is, the code will free the EFI if the
XFS_EFI_COMMITTED bit is *not* set, rather than if it is set. The
inverted logic "works" because if both EFI and EFD are committed,
then the first __xfs_efi_release() call clears the XFS_EFI_COMMITTED
bit, and the second frees the EFI item. Hence as long as
xfs_efi_item_committed() has been called, everything appears to be
fine.

It is the third case where the logic fails - where
xfs_efd_item_committed() is called before xfs_efi_item_committed(),
and that results in the EFI being freed before it has been
committed. That is the bug that triggered the shutdown, and hence
keeping track of whether the EFI has been committed or not is
insufficient to correctly order the EFI/EFD operations w.r.t. the
AIL.

What we really want is this: the EFI is always placed into the
AIL before the last reference goes away. The only way to guarantee
that is that the EFI is not freed until after it has been unpinned
*and* the EFD has been committed. That is, restructure the logic so
that the only case that can occur is the first case.

This can be done easily by replacing the XFS_EFI_COMMITTED with an
EFI reference count. The EFI is initialised with it's own count, and
that is not released until it is unpinned. However, there is a
complication to this method - the high level EFI/EFD code in
xfs_bmap_finish() does not hold direct references to the EFI
structure, and runs a transaction commit between the EFI and EFD
processing. Hence the EFI can be freed even before the EFD is
created using such a method.

Further, log recovery uses the AIL for tracking EFI/EFDs that need
to be recovered, but it uses the AIL *differently* to the EFI
transaction commit. Hence log recovery never pins or unpins EFIs, so
we can't drop the EFI reference count indirectly to free the EFI.

However, this doesn't prevent us from using a reference count here.
There is a 1:1 relationship between EFIs and EFDs, so when we
initialise the EFI we can take a reference count for the EFD as
well. This solves the xfs_bmap_finish() issue - the EFI will never
be freed until the EFD is processed. In terms of log recovery,
during the committing of the EFD we can look for the
XFS_EFI_RECOVERED bit being set and drop the EFI reference as well,
thereby ensuring everything works correctly there as well.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-05 13:25:35 -05:00
Rich Johnston
3d6e036193 xfs: Add ratelimited printk for different alert levels
Ratelimited printk will be useful in printing xfs messages which are otherwise
not required to be printed always due to their high rate (to prevent kernel ring
buffer from overflowing), while at the same time required to be printed.

Signed-off-by: Raghavendra D Prabhu <rprabhu@wnohang.net>
Reviewed-by: Rich Johnston <rjohnston@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
2013-04-03 13:20:39 -05:00