Based on a patch by Mark Wu <dwu@redhat.com>

Current index allocation in virtio-blk is based on a monotonically
increasing variable "index". This means we'll run out of numbers
after a while.  It also could cause confusion about the disk
name in the case of hot-plugging disks.
Change virtio-blk to use ida to allocate index, instead.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The P600 requires a small delay when changing states. Otherwise we may think
the board did not reset and we bail. This for kdump only and is particular
to the P600.
Signed-off-by: NMike Miller <mike.miller@hp.com>
Cc: stable@kernel.org
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The P600 requires a small delay when changing states. Otherwise we may think
the board did not reset and we bail. This for kdump only and is particular
to the P600.

Cc: stable@kernel.org
Signed-off-by: NJens Axboe <axboe@kernel.dk>

There are two windows of opportunity to cause a race when
processing a barrier request. This patch fixes this.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

The patch titled: "xen/blkback: Fix the inhibition to map pages
when discarding sector ranges." had the right idea except that
it used the wrong comparison operator. It had == instead of !=.

This fixes the bug where all (except discard) operations would
have been ignored.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

The 'operation' parameters are the ones provided to the bio layer while
the req->operation are the ones passed in between the backend and
frontend. We used the wrong 'operation' value to squash the
call to map pages when processing the discard operation resulting
in an hypercall that did nothing. Lets guard against going in the
mapping function by checking for the proper operation type.

CC: Li Dongyang <lidongyang@novell.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

We did not increment the amount of sectors written to disk
b/c we tested for the == WRITE which is incorrect - as the
operations are more of WRITE_FLUSH, WRITE_ODIRECT. This patch
fixes it by doing a & WRITE check.

CC: stable@kernel.org
Reported-by: NAndy Burns <xen.lists@burns.me.uk>
Suggested-by: NIan Campbell <Ian.Campbell@citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

We emulate the barrier requests by draining the outstanding bio's
and then sending the WRITE_FLUSH command. To drain the I/Os
we use the refcnt that is used during disconnect to wait for all
the I/Os before disconnecting from the frontend. We latch on its
value and if it reaches either the threshold for disconnect or when
there are no more outstanding I/Os, then we have drained all I/Os.
Suggested-by: NChristopher Hellwig <hch@infradead.org>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

... though after a failed xenbus_register_frontend() all may be lost.
Acked-by: NIan Campbell <ian.campbell@citrix.com>
Signed-off-by: NLaszlo Ersek <lersek@redhat.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Guard against issuing BLKIF_OP_WRITE_BARRIER or BLKIF_OP_FLUSH_CACHE
by checking whether we successfully negotiated with the backend.
The negotiation with the backend also sets the q->flush_flags which
fortunately for us is also used when submitting an bio to us. If
we don't support barriers or flushes it would be set to zero so
we should never end up having to deal with REQ_FLUSH | REQ_FUA.

However, other third party implementations of __make_request that
might be stacked on top of us might not be so smart, so lets fix this up.
Acked-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

This fixes the problem of three of those four memset()-s having
improper size arguments passed: Sizeof a pointer-typed expression
returns the size of the pointer, not that of the pointed to data.

It also reverts using kmalloc() instead of kzalloc() for the allocation
of the pending grant handles array, as that array gets fully
initialized in a subsequent loop.
Reported-by: NJulia Lawall <julia@diku.dk>
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

This patch fixes belows:

1. Fix code style issue.
2. Fix incorrect functions name in comments.
Signed-off-by: NJoe Jin <joe.jin@oracle.com>
Cc: Jens Axboe <jaxboe@fusionio.com>
Cc: Ian Campbell <Ian.Campbell@eu.citrix.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

When we get -EOPNOTSUPP response for a discard request, we will clear
the discard flag on the request queue so we won't attempt to send discard
requests to backend again, and this should be protected under rq->queue_lock.
However, when we setup the request queue, we pass blkif_io_lock to
blk_init_queue so rq->queue_lock is blkif_io_lock indeed, and this lock
is already taken when we are in blkif_interrpt, so remove the
spin_lock/spin_unlock when we clear the discard flag or we will end up
with deadlock here
Signed-off-by: NLi Dongyang <lidongyang@novell.com>
[v1: Updated description a bit and removed comment from source]
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

If the backend advertises 'feature-discard', then interrogate
the backend for alignment and granularity. Setup the request
queue with the appropiate values and send the discard operation
as required.
Signed-off-by: NLi Dongyang <lidongyang@novell.com>
[v1: Amended commit description]
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

..aka ATA TRIM/SCSI UNMAP command to be passed through the frontend
and used as appropiately by the backend. We also advertise
certain granulity parameters to the frontend so it can plug them in.
If the backend is a realy device - we just end up using
'blkdev_issue_discard' while for loopback devices - we just punch
a hole in the image file.
Signed-off-by: NLi Dongyang <lidongyang@novell.com>
[v1: Fixed up pr_debug and commit description]
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Now we use BLKIF_OP_DISCARD and add blkif_request_discard to blkif_request union,
the patch is taken from Owen Smith and Konrad, Thanks
Signed-off-by: NOwen Smith <owen.smith@citrix.com>
Signed-off-by: NLi Dongyang <lidongyang@novell.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

If the loop device is associated (lo->lo_state == Lo_bound), it will have
a valid bdev pointed to by lo->lo_device.  There is no reason to ever pass
an additional block_device pointer.
Signed-off-by: NAyan George <ayan.george@canonical.com>
Cc: Phillip Susi <psusi@cfl.rr.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: NAndrew Morton <akpm@google.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The loopback driver failed to emit the change uevent when auto releasing
the device.  Fixed lo_release() to pass the bdev to loop_clr_fd() so it
can emit the event.
Signed-off-by: NPhillip Susi <psusi@cfl.rr.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Ayan George <ayan@ayan.net>
Signed-off-by: NAndrew Morton <akpm@google.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This driver uses PCI_CLASS_REVISION instead of PCI_REVISION_ID, so it
wasn't converted by commit 44c10138 ("PCI: Change all drivers to
use pci_device->revision").
Signed-off-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Acked-by: NMike Miller <mike.miller@hp.com>
Cc: Chirag Kantharia <chirag.kantharia@hp.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: NAndrew Morton <akpm@google.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Automatic partition scanning can be requested individually per loop
device during its setup by setting LO_FLAGS_PARTSCAN. By default, no
partition tables are scanned.

Userspace can now always add and remove partitions from all loop
devices, regardless if the in-kernel partition scanner is enabled or
not.

The needed partition minor numbers are allocated from the extended
minors space, the main loop device numbers will continue to match the
loop minors, regardless of the number of partitions used.

  # grep . /sys/class/block/loop1/loop/*
  /sys/block/loop1/loop/autoclear:0
  /sys/block/loop1/loop/backing_file:/home/kay/data/stuff/part.img
  /sys/block/loop1/loop/offset:0
  /sys/block/loop1/loop/partscan:1
  /sys/block/loop1/loop/sizelimit:0

  # ls -l /dev/loop*
  brw-rw---- 1 root disk   7,   0 Aug 14 20:22 /dev/loop0
  brw-rw---- 1 root disk   7,   1 Aug 14 20:23 /dev/loop1
  brw-rw---- 1 root disk 259,   0 Aug 14 20:23 /dev/loop1p1
  brw-rw---- 1 root disk 259,   1 Aug 14 20:23 /dev/loop1p2
  brw-rw---- 1 root disk   7,  99 Aug 14 20:23 /dev/loop99
  brw-rw---- 1 root disk 259,   2 Aug 14 20:23 /dev/loop99p1
  brw-rw---- 1 root disk 259,   3 Aug 14 20:23 /dev/loop99p2
  crw------T 1 root root  10, 237 Aug 14 20:22 /dev/loop-control

Cc: Karel Zak  <kzak@redhat.com>
Cc: Davidlohr Bueso <dave@gnu.org>
Acked-By: NTejun Heo <tj@kernel.org>
Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

There are cases where suppressing partition scan is useful - e.g. for
lo devices and pseudo SATA devices which advertise to be a disk but
get upset on partition scan (some port multiplier control devices show
such behavior).

This patch adds GENHD_FL_NO_PART_SCAN which suppresses partition scan
regardless of the number of possible partitions.  disk_partitionable()
is renamed to disk_part_scan_enabled() as suppressing partition scan
doesn't imply the device can't be partitioned using
BLKPG_ADD/DEL_PARTITION calls from userland.  show_partition() now
directly tests disk_max_parts() to maintain backward-compatibility.

-v2: Updated to make it clear that only partition scan is suppressed
     not partitioning itself as suggested by Kay Sievers.
Signed-off-by: NTejun Heo <tj@kernel.org>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

This commit adds discard support for loop devices. Discard is usually
supported by SSD and thinly provisioned devices as a method for
reclaiming unused space. This is no different than trying to reclaim
back space which is not used by the file system on the image, but it
still occupies space on the host file system.

We can do the reclamation on file system which does support hole
punching. So when discard request gets to the loop driver we can
translate that to punch a hole to the underlying file, hence reclaim
the free space.

This is very useful for trimming down the size of the image to only what
is really used by the file system on that image. Fstrim may be used for
that purpose.

It has been tested on ext4, xfs and btrfs with the image file systems
ext4, ext3, xfs and btrfs. ext4, or ext6 image on ext4 file system has
some problems but it seems that ext4 punch hole implementation is
somewhat flawed and it is unrelated to this commit.

Also this is a very good method of validating file systems punch hole
implementation.

Note that when encryption is used, discard support is disabled, because
using it might leak some information useful for possible attacker.
Signed-off-by: NLukas Czerner <lczerner@redhat.com>
Reviewed-by: NJeff Moyer <jmoyer@redhat.com>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

ERROR: code indent should use tabs where possible
#30: FILE: drivers/block/nbd.c:578:
+^I        dev_info(disk_to_dev(lo->disk), "NBD_DISCONNECT\n");$

total: 1 errors, 0 warnings, 35 lines checked

NOTE: whitespace errors detected, you may wish to use scripts/cleanpatch or
      scripts/cleanfile

./patches/nbd-replace-some-printk-with-dev_warn-and-dev_info.patch has style problems, please review.

If any of these errors are false positives, please report
them to the maintainer, see CHECKPATCH in MAINTAINERS.

Please run checkpatch prior to sending patches

Cc: Paul Clements <Paul.Clements@steeleye.com>
Cc: WANG Cong <amwang@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

Signed-off-by: NWANG Cong <amwang@redhat.com>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

This is only an error, no need to use KERN_CRIT log level.
Signed-off-by: NWANG Cong <amwang@redhat.com>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

Signed-off-by: NWANG Cong <amwang@redhat.com>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

Signed-off-by: NWANG Cong <amwang@redhat.com>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

Signed-off-by: NWANG Cong <amwang@redhat.com>
Cc: Paul Clements <Paul.Clements@steeleye.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

Signed-off-by: NJoseph Handzik <joseph.t.handzik@beardog.cce.hp.com>
Acked-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

Signed-off-by: NJoseph Handzik <joseph.t.handzik@beardog.cce.hp.com>
Acked-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJens Axboe <jaxboe@fusionio.com>

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc: Fix build with DEBUG_PAGEALLOC enabled.

Commit d006199e72a9 ("serial: sh-sci: Regtype probing doesn't need to be
fatal.") made sci_init_single() return when sci_probe_regmap() succeeds,
although it should return when sci_probe_regmap() fails.  This causes
systems using the serial sh-sci driver to crash during boot.

Fix the problem by using the right return condition.
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The generic library code already exports the generic function, this was
left-over from the ARM-specific version that just got removed.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since commit 1eb19a12 ("lib/sha1: use the git implementation of
SHA-1"), the ARM SHA1 routines no longer work.  The reason? They
depended on the larger 320-byte workspace, and now the sha1 workspace is
just 16 words (64 bytes).  So the assembly version would overwrite the
stack randomly.

The optimized asm version is also probably slower than the new improved
C version, so there's no reason to keep it around.  At least that was
the case in git, where what appears to be the same assembly language
version was removed two years ago because the optimized C BLK_SHA1 code
was faster.
Reported-and-tested-by: NJoachim Eastwood <manabian@gmail.com>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Cc: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

task->cred is declared as __rcu, and access to other tasks' ->cred is,
indeed, protected.  Access to current->cred does not need rcu_dereference()
at all, since only the task itself can change its ->cred.  sparse, of
course, has no way of knowing that...

Add force-cast in current_cred(), make current_fsuid() et.al. use it.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Al points out that the do_follow_link() helper function really is
misnamed - it's about whether we should try to follow a symlink or not,
not about actually doing the following.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

After commit 3567866b: "RCUify freeing acls, let check_acl() go ahead in
RCU mode if acl is cached" posix_acl_permission is being called with an
unsupported flag and the permission check fails. This patch fixes the issue.
Signed-off-by: NAri Savolainen <ari.m.savolainen@gmail.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>