Commit graph

24104 commits

Author SHA1 Message Date
Dave Chinner
baf41a52b9 xfs: move extent records into bmalloca structure
Rather that putting extent records on the stack and then pointing to
them in the bmalloca structure which is in the same stack frame, put
the extent records directly in the bmalloca structure. This reduces
the number of args that need to be passed around.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:05 -05:00
Dave Chinner
1b16447ba2 xfs: pass bmalloca structure to xfs_bmap_isaeof
All the variables xfs_bmap_isaeof() is passed are contained within
the xfs_bmalloca structure. Pass that instead.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:05 -05:00
Christoph Hellwig
a5bd606ba6 xfs: remove xfs_bmap_add_extent
There is no real need to the xfs_bmap_add_extent, as the callers
know what kind of extents they need to it.  Removing it means
duplicating the extents to btree conversion logic in three places,
but overall it's still much simpler code and quite a bit less code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:05 -05:00
Christoph Hellwig
27a3f8f2de xfs: introduce xfs_bmap_last_extent
Add a common helper for finding the last extent in a file.

Largely based on a patch from Dave Chinner.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:05 -05:00
Dave Chinner
c0dc7828af xfs: rename xfs_bmapi to xfs_bmapi_write
Now that all the read-only users of xfs_bmapi have been converted to
use xfs_bmapi_read(), we can remove all the read-only handling cases
from xfs_bmapi().

Once this is done, rename xfs_bmapi to xfs_bmapi_write to reflect
the fact it is for allocation only. This enables us to kill the
XFS_BMAPI_WRITE flag as well.

Also clean up xfs_bmapi_write to the style used in the newly added
xfs_bmapi_read/delay functions.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:04 -05:00
Dave Chinner
b447fe5a05 xfs: factor unwritten extent map manipulations out of xfs_bmapi
To further improve the readability of xfs_bmapi(), factor the
unwritten extent conversion out into a separate function. This
removes large block of logic from the xfs_bmapi() code loop and
makes it easier to see the operational logic flow for xfs_bmapi().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:04 -05:00
Dave Chinner
7e47a4efde xfs: factor extent allocation out of xfs_bmapi
To further improve the readability of xfs_bmapi(), factor the extent
allocation out into a separate function. This removes a large block
of logic from the xfs_bmapi() code loop and makes it easier to see
the operational logic flow for xfs_bmapi().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:04 -05:00
Christoph Hellwig
1fd044d9c6 xfs: do not use xfs_bmap_add_extent for adding delalloc extents
We can just call xfs_bmap_add_extent_hole_delay directly to add a
delayed allocated regions to the extent tree, instead of going
through all the complexities of xfs_bmap_add_extent that aren't
needed for this simple case.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:04 -05:00
Christoph Hellwig
4403280aa5 xfs: introduce xfs_bmapi_delay()
Delalloc reservations are much simpler than allocations, so give
them a separate bmapi-level interface.  Using the previously added
xfs_bmapi_reserve_delalloc we get a function that is only minimally
more complicated than xfs_bmapi_read, which is far from the complexity
in xfs_bmapi.  Also remove the XFS_BMAPI_DELAY code after switching
over the only user to xfs_bmapi_delay.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:04 -05:00
Christoph Hellwig
b64dfe4e18 xfs: factor delalloc reservations out of xfs_bmapi
Move the reservation of delayed allocations, and addition of delalloc
regions to the extent trees into a new helper function.  For now
this adds some twisted goto logic to xfs_bmapi, but that will be
cleaned up in the following patches.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:04 -05:00
Dave Chinner
5b777ad517 xfs: remove xfs_bmapi_single()
Now we have xfs_bmapi_read, there is no need for xfs_bmapi_single().
Change the remaining caller over and kill the function.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:03 -05:00
Dave Chinner
5c8ed2021f xfs: introduce xfs_bmapi_read()
xfs_bmapi() currently handles both extent map reading and
allocation. As a result, the code is littered with "if (wr)"
branches to conditionally do allocation operations if required.
This makes the code much harder to follow and causes significant
indent issues with the code.

Given that read mapping is much simpler than allocation, we can
split out read mapping from xfs_bmapi() and reuse the logic that
we have already factored out do do all the hard work of handling the
extent map manipulations. The results in a much simpler function for
the common extent read operations, and will allow the allocation
code to be simplified in another commit.

Once xfs_bmapi_read() is implemented, convert all the callers of
xfs_bmapi() that are only reading extents to use the new function.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:03 -05:00
Dave Chinner
aef9a89586 xfs: factor extent map manipulations out of xfs_bmapi
To further improve the readability of xfs_bmapi(), factor the pure
extent map manipulations out into separate functions. This removes
large blocks of logic from the xfs_bmapi() code loop and makes it
easier to see the operational logic flow for xfs_bmapi().
    
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:03 -05:00
Christoph Hellwig
ecee76ba9d xfs: remove the nextents variable in xfs_bmapi
Instead of using a local variable that needs to updated when we modify
the extent map just check ifp->if_bytes directly where we use it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:03 -05:00
Christoph Hellwig
b9b984d784 xfs: remove impossible to read code in xfs_bmap_add_extent_delay_real
We already have the worst case blocks reserved, so xfs_icsb_modify_counters
won't fail in xfs_bmap_add_extent_delay_real.  In fact we've had an assert
to catch this case since day and it never triggered.  So remove the code
to try smaller reservations, and just return the error for that case in
addition to keeping the assert.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:03 -05:00
Christoph Hellwig
e7455e02e5 xfs: remove the first extent special case in xfs_bmap_add_extent
Both xfs_bmap_add_extent_hole_delay and xfs_bmap_add_extent_hole_real
already contain code to handle the case where there is no extent to
merge with, which is effectively the same as the code duplicated here.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:03 -05:00
Mitsuo Hayasaka
ed32201e65 xfs: Return -EIO when xfs_vn_getattr() failed
An attribute of inode can be fetched via xfs_vn_getattr() in XFS.
Currently it returns EIO, not negative value, when it failed.  As a
result, the system call returns not negative value even though an
error occured. The stat(2), ls and mv commands cannot handle this
error and do not work correctly.

This patch fixes this bug, and returns -EIO, not EIO when an error
is detected in xfs_vn_getattr().

Signed-off-by: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:02 -05:00
Chandra Seetharaman
eabbaf1182 xfs: Fix the incorrect comment in the header of _xfs_buf_find
Fix the incorrect comment in the header of the function
_xfs_buf_find().

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:02 -05:00
Chandra Seetharaman
2a30f36d90 xfs: Check the return value of xfs_trans_get_buf()
Check the return value of xfs_trans_get_buf() and fail
appropriately.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:01 -05:00
Chandra Seetharaman
b522950f0a xfs: Check the return value of xfs_buf_get()
Check the return value of xfs_buf_get() and fail appropriately.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:01 -05:00
Christoph Hellwig
04f658ee22 xfs: improve ioend error handling
Return unwritten extent conversion errors to aio_complete.

Skip both unwritten extent conversion and size updates if we had an
I/O error or the filesystem has been shut down.

Return -EIO to the aio/buffer completion handlers in case of a
forced shutdown.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:01 -05:00
Christoph Hellwig
c58cb165bd xfs: avoid direct I/O write vs buffered I/O race
Currently a buffered reader or writer can add pages to the pagecache
while we are waiting for the iolock in xfs_file_dio_aio_write.  Prevent
this by re-checking mapping->nrpages after we got the iolock, and if
nessecary upgrade the lock to exclusive mode.  To simplify this a bit
only take the ilock inside of xfs_file_aio_write_checks.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:01 -05:00
Christoph Hellwig
859f57ca00 xfs: avoid synchronous transactions when deleting attr blocks
Currently xfs_attr_inactive causes a synchronous transactions if we are
removing a file that has any extents allocated to the attribute fork, and
thus makes XFS extremely slow at removing files with out of line extended
attributes. The code looks a like a relict from the days before the busy
extent list, but with the busy extent list we avoid reusing data and attr
extents that have been freed but not commited yet, so this code is just
as superflous as the synchronous transactions for data blocks.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Bernd Schubert <bernd.schubert@itwm.fraunhofer.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:01 -05:00
Christoph Hellwig
4a06fd262d xfs: remove i_iocount
We now have an i_dio_count filed and surrounding infrastructure to wait
for direct I/O completion instead of i_icount, and we have never needed
to iocount waits for buffered I/O given that we only set the page uptodate
after finishing all required work.  Thus remove i_iocount, and replace
the actually needed waits with calls to inode_dio_wait.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:01 -05:00
Christoph Hellwig
2b3ffd7eb7 xfs: wait for I/O completion when writing out pages in xfs_setattr_size
The current code relies on the xfs_ioend_wait call later on to make sure
all I/O actually has completed.  The xfs_ioend_wait call will go away soon,
so prepare for that by using the waiting filemap function.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:00 -05:00
Christoph Hellwig
fc0063c447 xfs: reduce ioend latency
There is no reason to queue up ioends for processing in user context
unless we actually need it.  Just complete ioends that do not convert
unwritten extents or need a size update from the end_io context.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:00 -05:00
Christoph Hellwig
c859cdd1da xfs: defer AIO/DIO completions
We really shouldn't complete AIO or DIO requests until we have finished
the unwritten extent conversion and size update.  This means fsync never
has to pick up any ioends as all work has been completed when signalling
I/O completion.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:00 -05:00
Christoph Hellwig
398d25ef23 xfs: remove dead ENODEV handling in xfs_destroy_ioend
No driver returns ENODEV from it bio completion handler, not has this
ever been documented.  Remove the dead code dealing with it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:00 -05:00
Christoph Hellwig
c4e1c098ee xfs: use the "delwri" terminology consistently
And also remove the strange local lock and delwri list pointers in a few
functions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:00 -05:00
Christoph Hellwig
c2b006c1da xfs: let xfs_bwrite callers handle the xfs_buf_relse
Remove the xfs_buf_relse from xfs_bwrite and let the caller handle it to
mirror the delwri and read paths.

Also remove the mount pointer passed to xfs_bwrite, which is superflous now
that we have a mount pointer in the buftarg.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:15:00 -05:00
Christoph Hellwig
61551f1ee5 xfs: call xfs_buf_delwri_queue directly
Unify the ways we add buffers to the delwri queue by always calling
xfs_buf_delwri_queue directly.  The xfs_bdwrite functions is removed and
opencoded in its callers, and the two places setting XBF_DELWRI while a
buffer is locked and expecting xfs_buf_unlock to pick it up are converted
to call xfs_buf_delwri_queue directly, too.  Also replace the
XFS_BUF_UNDELAYWRITE macro with direct calls to xfs_buf_delwri_dequeue
to make the explicit queuing/dequeuing more obvious.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:14:59 -05:00
Christoph Hellwig
5a8ee6bafd xfs: move more delwri setup into xfs_buf_delwri_queue
Do not transfer a reference held by the caller to the buffer on the list,
or decrement it in xfs_buf_delwri_queue, but instead grab a new reference
if needed, and let the caller drop its own reference.  Also move setting
of the XBF_DELWRI and XBF_ASYNC flags into xfs_buf_delwri_queue, and
only do it if needed.  Note that for now xfs_buf_unlock already has
XBF_DELWRI, but that will change in the following patches.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:14:59 -05:00
Christoph Hellwig
527cfdf19d xfs: remove the unlock argument to xfs_buf_delwri_queue
We can just unlock the buffer in the caller, and the decrement of b_hold
would also be needed in the !unlock, we just never hit that case currently
given that the caller handles that case.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:14:59 -05:00
Christoph Hellwig
375ec69d2e xfs: remove delwri buffer handling from xfs_buf_iorequest
We cannot ever reach xfs_buf_iorequest for a buffer with XBF_DELWRI set,
given that all write handlers make sure that the buffer is remove from
the delwri queue before, and we never do reads with the XBF_DELWRI flag
set (which the code would not handle correctly anyway).

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:14:59 -05:00
Dave Chinner
7271d243f9 xfs: don't serialise adjacent concurrent direct IO appending writes
For append write workloads, extending the file requires a certain
amount of exclusive locking to be done up front to ensure sanity in
things like ensuring that we've zeroed any allocated regions
between the old EOF and the start of the new IO.

For single threads, this typically isn't a problem, and for large
IOs we don't serialise enough for it to be a problem for two
threads on really fast block devices. However for smaller IO and
larger thread counts we have a problem.

Take 4 concurrent sequential, single block sized and aligned IOs.
After the first IO is submitted but before it completes, we end up
with this state:

        IO 1    IO 2    IO 3    IO 4
      +-------+-------+-------+-------+
      ^       ^
      |       |
      |       |
      |       |
      |       \- ip->i_new_size
      \- ip->i_size

And the IO is done without exclusive locking because offset <=
ip->i_size. When we submit IO 2, we see offset > ip->i_size, and
grab the IO lock exclusive, because there is a chance we need to do
EOF zeroing. However, there is already an IO in progress that avoids
the need for IO zeroing because offset <= ip->i_new_size. hence we
could avoid holding the IO lock exlcusive for this. Hence after
submission of the second IO, we'd end up this state:

        IO 1    IO 2    IO 3    IO 4
      +-------+-------+-------+-------+
      ^               ^
      |               |
      |               |
      |               |
      |               \- ip->i_new_size
      \- ip->i_size

There is no need to grab the i_mutex of the IO lock in exclusive
mode if we don't need to invalidate the page cache. Taking these
locks on every direct IO effective serialises them as taking the IO
lock in exclusive mode has to wait for all shared holders to drop
the lock. That only happens when IO is complete, so effective it
prevents dispatch of concurrent direct IO writes to the same inode.

And so you can see that for the third concurrent IO, we'd avoid
exclusive locking for the same reason we avoided the exclusive lock
for the second IO.

Fixing this is a bit more complex than that, because we need to hold
a write-submission local value of ip->i_new_size to that clearing
the value is only done if no other thread has updated it before our
IO completes.....

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:14:59 -05:00
Dave Chinner
0c38a2512d xfs: don't serialise direct IO reads on page cache checks
There is no need to grab the i_mutex of the IO lock in exclusive
mode if we don't need to invalidate the page cache. Taking these
locks on every direct IO effective serialises them as taking the IO
lock in exclusive mode has to wait for all shared holders to drop
the lock. That only happens when IO is complete, so effective it
prevents dispatch of concurrent direct IO reads to the same inode.

Fix this by taking the IO lock shared to check the page cache state,
and only then drop it and take the IO lock exclusively if there is
work to be done. Hence for the normal direct IO case, no exclusive
locking will occur.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Tested-by: Joern Engel <joern@logfs.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2011-10-11 21:14:59 -05:00
Linus Torvalds
7fd21be75d Merge branch 'btrfs-3.0' of git://github.com/chrismason/linux
* 'btrfs-3.0' of git://github.com/chrismason/linux:
  Btrfs: force a page fault if we have a shorty copy on a page boundary
2011-10-03 12:17:44 -07:00
Josef Bacik
b6316429af Btrfs: force a page fault if we have a shorty copy on a page boundary
A user reported a problem where ceph was getting into 100% cpu usage while doing
some writing.  It turns out it's because we were doing a short write on a not
uptodate page, which means we'd fall back at one page at a time and fault the
page in.  The problem is our position is on the page boundary, so our fault in
logic wasn't actually reading the page, so we'd just spin forever or until the
page got read in by somebody else.  This will force a readpage if we end up
doing a short copy.  Alexandre could reproduce this easily with ceph and reports
it fixes his problem.  I also wrote a reproducer that no longer hangs my box
with this patch.  Thanks,

Reported-and-tested-by: Alexandre Oliva <aoliva@redhat.com>
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-09-30 15:23:54 -04:00
Linus Torvalds
b6c8069d35 vfs: remove LOOKUP_NO_AUTOMOUNT flag
That flag no longer makes sense, since we don't look up automount points
as eagerly any more.  Additionally, it turns out that the NO_AUTOMOUNT
handling was buggy to begin with: it would avoid automounting even for
cases where we really *needed* to do the automount handling, and could
return ENOENT for autofs entries that hadn't been instantiated yet.

With our new non-eager automount semantics, one discussion has been
about adding a AT_AUTOMOUNT flag to vfs_fstatat (and thus the
newfstatat() and fstatat64() system calls), but it's probably not worth
it: you can always force at least directory automounting by simply
adding the final '/' to the filename, which works for *all* of the stat
family system calls, old and new.

So AT_NO_AUTOMOUNT (and thus LOOKUP_NO_AUTOMOUNT) really were just a
result of our bad default behavior.

Acked-by: Ian Kent <raven@themaw.net>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-27 08:12:33 -07:00
Trond Myklebust
815d405cef VFS: Fix the remaining automounter semantics regressions
The concensus seems to be that system calls such as stat() etc should
not trigger an automount.  Neither should the l* versions.

This patch therefore adds a LOOKUP_AUTOMOUNT flag to tag those lookups
that _should_ trigger an automount on the last path element.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
[ Edited to leave out the cases that are already covered by LOOKUP_OPEN,
  LOOKUP_DIRECTORY and LOOKUP_CREATE - all of which also fundamentally
  force automounting for their own reasons   - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-26 19:16:46 -07:00
Linus Torvalds
d94c177bee vfs pathname lookup: Add LOOKUP_AUTOMOUNT flag
Since we've now turned around and made LOOKUP_FOLLOW *not* force an
automount, we want to add the ability to force an automount event on
lookup even if we don't happen to have one of the other flags that force
it implicitly (LOOKUP_OPEN, LOOKUP_DIRECTORY, LOOKUP_PARENT..)

Most cases will never want to use this, since you'd normally want to
delay automounting as long as possible, which usually implies
LOOKUP_OPEN (when we open a file or directory, we really cannot avoid
the automount any more).

But Trond argued sufficiently forcefully that at a minimum bind mounting
a file and quotactl will want to force the automount lookup.  Some other
cases (like nfs_follow_remote_path()) could use it too, although
LOOKUP_DIRECTORY would work there as well.

This commit just adds the flag and logic, no users yet, though.  It also
doesn't actually touch the LOOKUP_NO_AUTOMOUNT flag that is related, and
was made irrelevant by the same change that made us not follow on
LOOKUP_FOLLOW.

Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Ian Kent <raven@themaw.net>
Cc: Jeff Layton <jlayton@redhat.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Greg KH <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-26 17:44:55 -07:00
Linus Torvalds
fed678dc8a Merge branch 'for-linus' of git://git.kernel.dk/linux-block
* 'for-linus' of git://git.kernel.dk/linux-block:
  floppy: use del_timer_sync() in init cleanup
  blk-cgroup: be able to remove the record of unplugged device
  block: Don't check QUEUE_FLAG_SAME_COMP in __blk_complete_request
  mm: Add comment explaining task state setting in bdi_forker_thread()
  mm: Cleanup clearing of BDI_pending bit in bdi_forker_thread()
  block: simplify force plug flush code a little bit
  block: change force plug flush call order
  block: Fix queue_flag update when rq_affinity goes from 2 to 1
  block: separate priority boosting from REQ_META
  block: remove READ_META and WRITE_META
  xen-blkback: fixed indentation and comments
  xen-blkback: Don't disconnect backend until state switched to XenbusStateClosed.
2011-09-21 13:20:21 -07:00
Dave Hansen
32ef43848f teach /proc/$pid/numa_maps about transparent hugepages
This is modeled after the smaps code.

It detects transparent hugepages and then does a single gather_stats()
for the page as a whole.  This has two benifits:
 1. It is more efficient since it does many pages in a single shot.
 2. It does not have to break down the huge page.

Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-21 13:15:44 -07:00
Dave Hansen
3200a8aaab break out numa_maps gather_pte_stats() checks
gather_pte_stats() does a number of checks on a target page
to see whether it should even be considered for statistics.
This breaks that code out in to a separate function so that
we can use it in the transparent hugepage case in the next
patch.

Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
Acked-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Christoph Lameter <cl@gentwo.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-21 13:15:44 -07:00
Dave Hansen
eb4866d006 make /proc/$pid/numa_maps gather_stats() take variable page size
We need to teach the numa_maps code about transparent huge pages.  The
first step is to teach gather_stats() that the pte it is dealing with
might represent more than one page.

Note that will we use this in a moment for transparent huge pages since
they have use a single pmd_t which _acts_ as a "surrogate" for a bunch
of smaller pte_t's.

I'm a _bit_ unhappy that this interface counts in hugetlbfs page sizes
for hugetlbfs pages and PAGE_SIZE for normal pages.  That means that to
figure out how many _bytes_ "dirty=1" means, you must first know the
hugetlbfs page size.  That's easier said than done especially if you
don't have visibility in to the mount.

But, that's probably a discussion for another day especially since it
would change behavior to fix it.  But, just in case anyone wonders why
this patch only passes a '1' in the hugetlb case...

Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-21 13:15:44 -07:00
Linus Torvalds
43a964a7bf Merge branch 'for-linus' of git://github.com/chrismason/linux
* 'for-linus' of git://github.com/chrismason/linux:
  Btrfs: reserve sufficient space for ioctl clone
2011-09-20 14:22:55 -07:00
Chris Mason
0a7a0519d1 Merge branch 'btrfs-3.0' into for-linus 2011-09-20 14:49:29 -04:00
Sage Weil
b6f3409b21 Btrfs: reserve sufficient space for ioctl clone
Fix a crash/BUG_ON in the clone ioctl due to insufficient reservation. We
need to reserve space for:

 - adjusting the old extent (possibly splitting it)
 - adding the new extent
 - updating the inode

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-09-20 14:48:51 -04:00
Shirish Pargaonkar
cfbd6f84c2 cifs: Fix broken sec=ntlmv2/i sec option (try #2)
Fix sec=ntlmv2/i authentication option during mount of Samba shares.

cifs client was coding ntlmv2 response incorrectly.
All that is needed in temp as specified in MS-NLMP seciton 3.3.2

"Define ComputeResponse(NegFlg, ResponseKeyNT, ResponseKeyLM,
CHALLENGE_MESSAGE.ServerChallenge, ClientChallenge, Time, ServerName)

as
Set temp to ConcatenationOf(Responserversion, HiResponserversion,
Z(6), Time, ClientChallenge, Z(4), ServerName, Z(4)"

is MsvAvNbDomainName.

For sec=ntlmsspi, build_av_pair is not used, a blob is plucked from
type 2 response sent by the server to use in authentication.

I tested sec=ntlmv2/i and sec=ntlmssp/i mount options against
Samba (3.6) and Windows - XP, 2003 Server and 7.
They all worked.

Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-09-19 21:16:58 -05:00
Steve French
c9c7fa0064 Fix the conflict between rwpidforward and rw mount options
Both these options are started with "rw" - that's why the first one
isn't switched on even if it is specified. Fix this by adding a length
check for "rw" option check.

Cc: <stable@kernel.org>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2011-09-19 21:16:20 -05:00