fuse: fix nlink after unlink

Anand Avati reports that the following sequence of system calls fail on a fuse
filesystem:


 	create("filename") => 0
 	link("filename", "linkname") => 0
 	unlink("filename") => 0
 	link("linkname", "filename") => -ENOENT ### BUG ###

vfs_link() fails with ENOENT if i_nlink is zero, this is done to prevent
resurrecting already deleted files.

Fuse clears i_nlink on unlink even if there are other links pointing to the
file.

Reported-by: Anand Avati <avati@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
fuse: O_DIRECT support for files

Implement ->direct_IO() method in aops. The ->direct_IO() method combines
the existing fuse_direct_read/fuse_direct_write methods to implement
O_DIRECT functionality.

Reaching ->direct_IO() in the read path via generic_file_aio_read ensures
proper synchronization with page cache with its existing framework.

Reaching ->direct_IO() in the write path via fuse_file_aio_write is made
to come via generic_file_direct_write() which makes it play nice with
the page cache w.r.t other mmap pages etc.

On files marked 'direct_io' by the filesystem server, IO always follows
the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT)
and it always succeeds.

On files not marked with 'direct_io' by the filesystem server, the IO
path depends on O_DIRECT flag by the application. This can be passed
at the time of open() as well as via fcntl().

Note that asynchronous O_DIRECT iocb jobs are completed synchronously
always (this has been the case with FUSE even before this patch)

Signed-off-by: Anand Avati <avati@redhat.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
xen/blkback: use grant-table.c hypercall wrappers

Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
xen/blkback: Enable blkback on HVM guests

Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
xen-blkfront: use bitmap_set() and bitmap_clear()

Use bitmap_set and bitmap_clear rather than modifying individual bits
in a memory region.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: xen-devel@lists.xensource.com
Cc: virtualization@lists.linux-foundation.org
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
xen/blkfront: don't put bdev right after getting it

We should hang onto bdev until we're done with it.

Signed-off-by: Andrew Jones <drjones@redhat.com>
[v1: Fixed up git commit description]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
xen-blkfront: make blkif_io_lock spinlock per-device

This patch moves the global blkif_io_lock to the per-device structure. The
spinlock seems to exists for two reasons: to disable IRQs when in the interrupt
handlers for blkfront, and to protect the blkfront VBDs when a detachment is
requested.

Having a global blkif_io_lock doesn't make sense given the use case, and it
drastically hinders performance due to contention. All VBDs with pending IOs
have to take the lock in order to get work done, which serializes everything
pretty badly.

Signed-off-by: Steven Noonan <snoonan@amazon.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
cciss: Initialize scsi host max_sectors for tape drive support

The default is too small (1024 blocks), use h->cciss_max_sectors (8192 blocks)
Without this change, if you try to set the block size of a tape drive above
512*1024, via "mt -f /dev/st0 setblk nnn" where nnn is greater than 524288,
it won't work right.

Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
cciss: Fix scsi tape io with more than 255 scatter gather elements

The total number of scatter gather elements in the CISS command
used by the scsi tape code was being cast to a u8, which can hold
at most 255 scatter gather elements.  It should have been cast to
a u16.  Without this patch the command gets rejected by the controller
since the total scatter gather count did not add up to the right
value resulting in an i/o error.

Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
block: blk_alloc_queue_node(): use caller's GFP flags instead of GFP_KERNEL

We should use the GFP flags that the caller specified instead of picking
our own.  All the callers specify GFP_KERNEL so this doesn't make a
difference to how the kernel runs, it's just a cleanup.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
mtip32xx: fix incorrect value set for drv_cleanup_done, and re-initialize and start port in mtip_restart_port()

This patch includes two changes:
	* fix incorrect value set for drv_cleanup_done
	* re-initialize and start port in mtip_restart_port()

Signed-off-by: Asai Thambi S P <asamymuthupa@micron.com>
Signed-off-by: Sam Bradshaw <sbradshaw@micron.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
ioat: fix size of 'completion' for Xen

Starting with v3.2 Jonathan reports that Xen crashes loading the ioatdma
driver.  A debug run shows:

  ioatdma 0000:00:16.4: desc[0]: (0x300cc7000->0x300cc7040) cookie: 0 flags: 0x2 ctl: 0x29 (op: 0 int_en: 1 compl: 1)
  ...
  ioatdma 0000:00:16.4: ioat_get_current_completion: phys_complete: 0xcc7000

...which shows that in this environment GFP_KERNEL memory may be backed
by a 64-bit dma address.  This breaks the driver's assumption that an
unsigned long should be able to contain the physical address for
descriptor memory.  Switch to dma_addr_t which beyond being the right
size, is the true type for the data i.e. an io-virtual address
inidicating the engine's last processed descriptor.

[stable: 3.2+]
Cc: <stable@vger.kernel.org>
Reported-by: Jonathan Nieder <jrnieder@gmail.com>
Reported-by: William Dauchy <wdauchy@gmail.com>
Tested-by: William Dauchy <wdauchy@gmail.com>
Tested-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
xen/blkback: Squash the discard support for 'file' and 'phy' type.

The only reason for the distinction was for the special case of
'file' (which is assumed to be loopback device), was to reach inside
the loopback device, find the underlaying file, and call fallocate on it.
Fortunately "xen-blkback: convert hole punching to discard request on
loop devices" removes that use-case and we now based the discard
support based on blk_queue_discard(q) and extract all appropriate
parameters from the 'struct request_queue'.

CC: Li Dongyang <lidongyang@novell.com>
Acked-by: Jan Beulich <JBeulich@suse.com>
[v1: Dropping pointless initializer and keeping blank line]
[v2: Remove the kfree as it is not used anymore]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
xen/blkback: Make optional features be really optional.

They were using the xenbus_dev_fatal() function which would
change the state of the connection immediately. Which is not
what we want when we advertise optional features.

So make 'feature-discard','feature-barrier','feature-flush-cache'
optional.

Suggested-by: Jan Beulich <JBeulich@suse.com>
[v1: Made the discard function void and static]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Merge branch 'stable/for-jens-3.4-bugfixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen into for-3.4/drivers

Konrad writes:

I've two small fixes for the xen-blkback - and I think one more will show up
eventually (a partial revert), but not sure when. So in the spirit of keeping
the patches flowing, please git pull the following branch.
GFS2: put glock reference in error patch of read_rindex_entry

This patch fixes the error path of function read_rindex_entry
so that it correctly gives up its glock reference in cases where
there is a race to re-read the rindex after gfs2_grow.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
GFS2: use depends instead of select in kconfig

Avoids having to duplicate the dependencies of what is 'select'ed (and on
down...)

Those dependencies are currently incomplete, leading to broken builds with
GFS2_FS_LOCKING_DLM=y and IP_SCTP=n.

Signed-off-by: Benjamin Poirier <bpoirier@suse.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
iop-adma: Corrected array overflow in RAID6 Xscale(R) test.

Bug: cppcheck reported overflow in array assignment (for loop walks
0 to IOP_ADMA_NUM_SRC_TEST+2, array size is IOP_ADMA_NUM_SRC_TEST).

Reported as: https://bugzilla.kernel.org/show_bug.cgi?id=42677

Test code pq_src array was grown by two elements to correspond with actual
usage (IOP_ADMA_NUM_SRC_TEST+2), stack consumption was kept constant by
modifying the pq_dest two element array which is only used when pq_src
is referenced up to IOP_ADMA_NUM_SRC_TEST elements into the address
of the new last two elements of the pq_src array. This is presumed to
be the original intent but would be reliant on compilers always having
pq_dest contiguous with the final element of pq_src.

Note: This is a re-send of a request for review from two weeks ago.
Looking for review (or shootdown), adding LKML to list for a wider
audience. Thanks.

Updated per review comments of Sergei Shtylyov <sshtylyov@mvista.com>

Signed-off-by: Don Morris <don.morris@hp.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
virtio-blk: Call revalidate_disk() upon online disk resize

If a virtio disk is open in guest and a disk resize operation is done,
(virsh blockresize), new size is not visible to tools like "fdisk -l".
This seems to be happening as we update only part->nr_sects and not
bdev->bd_inode size.

Call revalidate_disk() which should take care of it. I tested growing disk
size of already open disk and it works for me.

Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
sh: fix up fallout from system.h disintegration.

Quite a bit of fallout all over the place, nothing terribly exciting.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>