Commit Graph

275 Commits

Author SHA1 Message Date
Jaegeuk Kim 5db470e229 loop: drop caches if offset or block_size are changed
If we don't drop caches used in old offset or block_size, we can get old data
from new offset/block_size, which gives unexpected data to user.

For example, Martijn found a loopback bug in the below scenario.
1) LOOP_SET_FD loads first two pages on loop file
2) LOOP_SET_STATUS64 changes the offset on the loop file
3) mount is failed due to the cached pages having wrong superblock

Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Reported-by: Martijn Coenen <maco@google.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-01-09 20:51:44 -07:00
Chengguang Xu c41103691b block: loop: remove redundant code
Code cleanup for removing redundant break in switch case.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-22 14:45:31 -07:00
Chengguang Xu 38a3499f6d block: loop: check error using IS_ERR instead of IS_ERR_OR_NULL in loop_add()
blk_mq_init_queue() will not return NULL pointer to its caller,
so it's better to replace IS_ERR_OR_NULL using IS_ERR in loop_add().

If in the future things change to check NULL pointer inside loop_add(),
we should return -ENOMEM as return code instead of PTR_ERR(NULL).

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-16 09:01:38 -07:00
Dennis Zhou db6638d7d1 blkcg: remove bio->bi_css and instead use bio->bi_blkg
Prior patches ensured that any bio that interacts with a request_queue
is properly associated with a blkg. This makes bio->bi_css unnecessary
as blkg maintains a reference to blkcg already.

This removes the bio field bi_css and transfers corresponding uses to
access via bi_blkg.

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:37 -07:00
Tetsuo Handa 628bd85947 loop: Fix double mutex_unlock(&loop_ctl_mutex) in loop_control_ioctl()
Commit 0a42e99b58 ("loop: Get rid of loop_index_mutex") forgot to
remove mutex_unlock(&loop_ctl_mutex) from loop_control_ioctl() when
replacing loop_index_mutex with loop_ctl_mutex.

Fixes: 0a42e99b58 ("loop: Get rid of loop_index_mutex")
Reported-by: syzbot <syzbot+c0138741c2290fc5e63f@syzkaller.appspotmail.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-12 08:44:06 -07:00
Jan Kara c28445fa06 loop: Get rid of 'nested' acquisition of loop_ctl_mutex
The nested acquisition of loop_ctl_mutex (->lo_ctl_mutex back then) has
been introduced by commit f028f3b2f9 "loop: fix circular locking in
loop_clr_fd()" to fix lockdep complains about bd_mutex being acquired
after lo_ctl_mutex during partition rereading. Now that these are
properly fixed, let's stop fooling lockdep.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-08 06:30:37 -07:00
Jan Kara 1dded9acf6 loop: Avoid circular locking dependency between loop_ctl_mutex and bd_mutex
Code in loop_change_fd() drops reference to the old file (and also the
new file in a failure case) under loop_ctl_mutex. Similarly to a
situation in loop_set_fd() this can create a circular locking dependency
if this was the last reference holding the file open. Delay dropping of
the file reference until we have released loop_ctl_mutex.

Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-08 06:30:36 -07:00
Jan Kara 0da03cab87 loop: Fix deadlock when calling blkdev_reread_part()
Calling blkdev_reread_part() under loop_ctl_mutex causes lockdep to
complain about circular lock dependency between bdev->bd_mutex and
lo->lo_ctl_mutex. The problem is that on loop device open or close
lo_open() and lo_release() get called with bdev->bd_mutex held and they
need to acquire loop_ctl_mutex. OTOH when loop_reread_partitions() is
called with loop_ctl_mutex held, it will call blkdev_reread_part() which
acquires bdev->bd_mutex. See syzbot report for details [1].

Move call to blkdev_reread_part() in __loop_clr_fd() from under
loop_ctl_mutex to finish fixing of the lockdep warning and the possible
deadlock.

[1] https://syzkaller.appspot.com/bug?id=bf154052f0eea4bc7712499e4569505907d1588

Reported-by: syzbot <syzbot+4684a000d5abdade83fac55b1e7d1f935ef1936e@syzkaller.appspotmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-08 06:30:32 -07:00
Jan Kara 85b0a54a82 loop: Move loop_reread_partitions() out of loop_ctl_mutex
Calling loop_reread_partitions() under loop_ctl_mutex causes lockdep to
complain about circular lock dependency between bdev->bd_mutex and
lo->lo_ctl_mutex. The problem is that on loop device open or close
lo_open() and lo_release() get called with bdev->bd_mutex held and they
need to acquire loop_ctl_mutex. OTOH when loop_reread_partitions() is
called with loop_ctl_mutex held, it will call blkdev_reread_part() which
acquires bdev->bd_mutex. See syzbot report for details [1].

Move all calls of loop_rescan_partitions() out of loop_ctl_mutex to
avoid lockdep warning and fix deadlock possibility.

[1] https://syzkaller.appspot.com/bug?id=bf154052f0eea4bc7712499e4569505907d1588

Reported-by: syzbot <syzbot+4684a000d5abdade83fac55b1e7d1f935ef1936e@syzkaller.appspotmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-08 06:30:31 -07:00
Jan Kara d57f3374ba loop: Move special partition reread handling in loop_clr_fd()
The call of __blkdev_reread_part() from loop_reread_partition() happens
only when we need to invalidate partitions from loop_release(). Thus
move a detection for this into loop_clr_fd() and simplify
loop_reread_partition().

This makes loop_reread_partition() safe to use without loop_ctl_mutex
because we use only lo->lo_number and lo->lo_file_name in case of error
for reporting purposes (thus possibly reporting outdate information is
not a big deal) and we are safe from 'lo' going away under us by
elevated lo->lo_refcnt.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-08 06:30:30 -07:00
Jan Kara c371077000 loop: Push loop_ctl_mutex down to loop_change_fd()
Push loop_ctl_mutex down to loop_change_fd(). We will need this to be
able to call loop_reread_partitions() without loop_ctl_mutex.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-08 06:30:28 -07:00
Jan Kara 757ecf40b7 loop: Push loop_ctl_mutex down to loop_set_fd()
Push lo_ctl_mutex down to loop_set_fd(). We will need this to be able to
call loop_reread_partitions() without lo_ctl_mutex.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-08 06:30:27 -07:00
Jan Kara 550df5fdac loop: Push loop_ctl_mutex down to loop_set_status()
Push loop_ctl_mutex down to loop_set_status(). We will need this to be
able to call loop_reread_partitions() without loop_ctl_mutex.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-08 06:30:22 -07:00
Jan Kara 4a5ce9ba58 loop: Push loop_ctl_mutex down to loop_get_status()
Push loop_ctl_mutex down to loop_get_status() to avoid the unusual
convention that the function gets called with loop_ctl_mutex held and
releases it.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-08 06:30:20 -07:00
Jan Kara 7ccd0791d9 loop: Push loop_ctl_mutex down into loop_clr_fd()
loop_clr_fd() has a weird locking convention that is expects
loop_ctl_mutex held, releases it on success and keeps it on failure.
Untangle the mess by moving locking of loop_ctl_mutex into
loop_clr_fd().

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-08 06:30:19 -07:00
Jan Kara a2505b799a loop: Split setting of lo_state from loop_clr_fd
Move setting of lo_state to Lo_rundown out into the callers. That will
allow us to unlock loop_ctl_mutex while the loop device is protected
from other changes by its special state.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-08 06:30:18 -07:00
Jan Kara a13165441d loop: Push lo_ctl_mutex down into individual ioctls
Push acquisition of lo_ctl_mutex down into individual ioctl handling
branches. This is a preparatory step for pushing the lock down into
individual ioctl handling functions so that they can release the lock as
they need it. We also factor out some simple ioctl handlers that will
not need any special handling to reduce unnecessary code duplication.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-08 06:30:16 -07:00
Jan Kara 0a42e99b58 loop: Get rid of loop_index_mutex
Now that loop_ctl_mutex is global, just get rid of loop_index_mutex as
there is no good reason to keep these two separate and it just
complicates the locking.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-08 06:30:15 -07:00
Jan Kara 967d1dc144 loop: Fold __loop_release into loop_release
__loop_release() has a single call site. Fold it there. This is
currently not a huge win but it will make following replacement of
loop_index_mutex more obvious.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-08 06:30:14 -07:00
Tetsuo Handa 310ca162d7 block/loop: Use global lock for ioctl() operation.
syzbot is reporting NULL pointer dereference [1] which is caused by
race condition between ioctl(loop_fd, LOOP_CLR_FD, 0) versus
ioctl(other_loop_fd, LOOP_SET_FD, loop_fd) due to traversing other
loop devices at loop_validate_file() without holding corresponding
lo->lo_ctl_mutex locks.

Since ioctl() request on loop devices is not frequent operation, we don't
need fine grained locking. Let's use global lock in order to allow safe
traversal at loop_validate_file().

Note that syzbot is also reporting circular locking dependency between
bdev->bd_mutex and lo->lo_ctl_mutex [2] which is caused by calling
blkdev_reread_part() with lock held. This patch does not address it.

[1] https://syzkaller.appspot.com/bug?id=f3cfe26e785d85f9ee259f385515291d21bd80a3
[2] https://syzkaller.appspot.com/bug?id=bf154052f0eea4bc7712499e4569505907d15889

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot <syzbot+bf89c128e05dd6c62523@syzkaller.appspotmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-08 06:30:11 -07:00
Tetsuo Handa b1ab5fa309 block/loop: Don't grab "struct file" for vfs_getattr() operation.
vfs_getattr() needs "struct path" rather than "struct file".
Let's use path_get()/path_put() rather than get_file()/fput().

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-08 06:30:09 -07:00
Linus Torvalds 5f21585384 for-linus-20181102
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Merge tag 'for-linus-20181102' of git://git.kernel.dk/linux-block

Pull block layer fixes from Jens Axboe:
 "The biggest part of this pull request is the revert of the blkcg
  cleanup series. It had one fix earlier for a stacked device issue, but
  another one was reported. Rather than play whack-a-mole with this,
  revert the entire series and try again for the next kernel release.

  Apart from that, only small fixes/changes.

  Summary:

   - Indentation fixup for mtip32xx (Colin Ian King)

   - The blkcg cleanup series revert (Dennis Zhou)

   - Two NVMe fixes. One fixing a regression in the nvme request
     initialization in this merge window, causing nvme-fc to not work.
     The other is a suspend/resume p2p resource issue (James, Keith)

   - Fix sg discard merge, allowing us to merge in cases where we didn't
     before (Jianchao Wang)

   - Call rq_qos_exit() after the queue is frozen, preventing a hang
     (Ming)

   - Fix brd queue setup, fixing an oops if we fail setting up all
     devices (Ming)"

* tag 'for-linus-20181102' of git://git.kernel.dk/linux-block:
  nvme-pci: fix conflicting p2p resource adds
  nvme-fc: fix request private initialization
  blkcg: revert blkcg cleanups series
  block: brd: associate with queue until adding disk
  block: call rq_qos_exit() after queue is frozen
  mtip32xx: clean an indentation issue, remove extraneous tabs
  block: fix the DISCARD request merge
2018-11-02 11:25:48 -07:00
Linus Torvalds 9931a07d51 Merge branch 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull AFS updates from Al Viro:
 "AFS series, with some iov_iter bits included"

* 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits)
  missing bits of "iov_iter: Separate type from direction and use accessor functions"
  afs: Probe multiple fileservers simultaneously
  afs: Fix callback handling
  afs: Eliminate the address pointer from the address list cursor
  afs: Allow dumping of server cursor on operation failure
  afs: Implement YFS support in the fs client
  afs: Expand data structure fields to support YFS
  afs: Get the target vnode in afs_rmdir() and get a callback on it
  afs: Calc callback expiry in op reply delivery
  afs: Fix FS.FetchStatus delivery from updating wrong vnode
  afs: Implement the YFS cache manager service
  afs: Remove callback details from afs_callback_break struct
  afs: Commit the status on a new file/dir/symlink
  afs: Increase to 64-bit volume ID and 96-bit vnode ID for YFS
  afs: Don't invoke the server to read data beyond EOF
  afs: Add a couple of tracepoints to log I/O errors
  afs: Handle EIO from delivery function
  afs: Fix TTL on VL server and address lists
  afs: Implement VL server rotation
  afs: Improve FS server rotation error handling
  ...
2018-11-01 19:58:52 -07:00
Dennis Zhou b5f2954d30 blkcg: revert blkcg cleanups series
This reverts a series committed earlier due to null pointer exception
bug report in [1]. It seems there are edge case interactions that I did
not consider and will need some time to understand what causes the
adverse interactions.

The original series can be found in [2] with a follow up series in [3].

[1] https://www.spinics.net/lists/cgroups/msg20719.html
[2] https://lore.kernel.org/lkml/20180911184137.35897-1-dennisszhou@gmail.com/
[3] https://lore.kernel.org/lkml/20181020185612.51587-1-dennis@kernel.org/

This reverts the following commits:
d459d853c2, b2c3fa5467, 101246ec02, b3b9f24f5f, e2b0989954,
f0fcb3ec89, c839e7a03f, bdc2491708, 74b7c02a9b, 5bf9a1f3b4,
a7b39b4e96, 07b05bcc32, 49f4c2dc2b, 27e6fa996c

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-11-01 19:59:53 -06:00
David Howells aa563d7bca iov_iter: Separate type from direction and use accessor functions
In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.

Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements.  This makes it easier to add further
iterator types.  Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.

Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself.  Only the direction is required.

Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24 00:41:07 +01:00
Dennis Zhou (Facebook) c839e7a03f blkcg: remove bio->bi_css and instead use bio->bi_blkg
Prior patches ensured that all bios are now associated with some blkg.
This now makes bio->bi_css unnecessary as blkg maintains a reference to
the blkcg already.

This patch removes the field bi_css and transfers corresponding uses to
access via bi_blkg.

Signed-off-by: Dennis Zhou <dennisszhou@gmail.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-09-21 20:29:13 -06:00
Gustavo A. R. Silva d893ff8603 block/loop: mark expected switch fall-through
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-09 09:07:53 -06:00
Colin Ian King f4354a94e2 loop: remove redundant pointer inode
Pointer inode is being assigned but is never used hence it is redundant
and can be removed.

Cleans up clang warning:
warning: variable 'inode' set but not used [-Wunused-but-set-variable]

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-09 09:07:53 -06:00
Linus Torvalds 29119529d8 for-linus-20180706
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Merge tag 'for-linus-20180706' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "Two minor fixes for this series:

   - add LOOP_SET_BLOCK_SIZE as compat ioctl (Evan Green)

   - drbd use-after-free fix (Lars Ellenberg)"

* tag 'for-linus-20180706' of git://git.kernel.dk/linux-block:
  loop: Add LOOP_SET_BLOCK_SIZE in compat ioctl
  drbd: fix access after free
2018-07-06 19:13:42 -07:00
Evan Green 9fea4b3952 loop: Add LOOP_SET_BLOCK_SIZE in compat ioctl
This change adds LOOP_SET_BLOCK_SIZE as one of the supported ioctls
in lo_compat_ioctl. It only takes an unsigned long argument, and
in practice a 32-bit value works fine.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-07-03 07:52:34 -06:00
Kees Cook 6da2ec5605 treewide: kmalloc() -> kmalloc_array()
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This
patch replaces cases of:

        kmalloc(a * b, gfp)

with:
        kmalloc_array(a * b, gfp)

as well as handling cases of:

        kmalloc(a * b * c, gfp)

with:

        kmalloc(array3_size(a, b, c), gfp)

as it's slightly less ugly than:

        kmalloc_array(array_size(a, b), c, gfp)

This does, however, attempt to ignore constant size factors like:

        kmalloc(4 * 1024, gfp)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The tools/ directory was manually excluded, since it has its own
implementation of kmalloc().

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
  kmalloc(
-	(sizeof(TYPE)) * E
+	sizeof(TYPE) * E
  , ...)
|
  kmalloc(
-	(sizeof(THING)) * E
+	sizeof(THING) * E
  , ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
  kmalloc(
-	sizeof(u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * (COUNT)
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(__u8) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(char) * COUNT
+	COUNT
  , ...)
|
  kmalloc(
-	sizeof(unsigned char) * COUNT
+	COUNT
  , ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_ID)
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_ID
+	COUNT_ID, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (COUNT_CONST)
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * COUNT_CONST
+	COUNT_CONST, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_ID)
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_ID
+	COUNT_ID, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (COUNT_CONST)
+	COUNT_CONST, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * COUNT_CONST
+	COUNT_CONST, sizeof(THING)
  , ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

- kmalloc
+ kmalloc_array
  (
-	SIZE * COUNT
+	COUNT, SIZE
  , ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
  kmalloc(
-	sizeof(TYPE) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(TYPE) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(TYPE))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * (COUNT) * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * (STRIDE)
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
|
  kmalloc(
-	sizeof(THING) * COUNT * STRIDE
+	array3_size(COUNT, STRIDE, sizeof(THING))
  , ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
  kmalloc(
-	sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(THING1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(THING1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * COUNT
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
|
  kmalloc(
-	sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+	array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
  , ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
  kmalloc(
-	(COUNT) * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * STRIDE * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	(COUNT) * (STRIDE) * (SIZE)
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
|
  kmalloc(
-	COUNT * STRIDE * SIZE
+	array3_size(COUNT, STRIDE, SIZE)
  , ...)
)

// Any remaining multi-factor products, first at least 3-factor products,
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(
-	(E1) * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * E3
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	(E1) * (E2) * (E3)
+	array3_size(E1, E2, E3)
  , ...)
|
  kmalloc(
-	E1 * E2 * E3
+	array3_size(E1, E2, E3)
  , ...)
)

// And then all remaining 2 factors products when they're not all constants,
// keeping sizeof() as the second factor argument.
@@
expression THING, E1, E2;
type TYPE;
constant C1, C2, C3;
@@

(
  kmalloc(sizeof(THING) * C2, ...)
|
  kmalloc(sizeof(TYPE) * C2, ...)
|
  kmalloc(C1 * C2 * C3, ...)
|
  kmalloc(C1 * C2, ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * (E2)
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(TYPE) * E2
+	E2, sizeof(TYPE)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * (E2)
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	sizeof(THING) * E2
+	E2, sizeof(THING)
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * E2
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	(E1) * (E2)
+	E1, E2
  , ...)
|
- kmalloc
+ kmalloc_array
  (
-	E1 * E2
+	E1, E2
  , ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Linus Torvalds a3818841bd for-linus-20180608
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Merge tag 'for-linus-20180608' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "A few fixes for this merge window, where some of them should go in
  sooner rather than later, hence a new pull this week. This pull
  request contains:

   - Set of NVMe fixes, mostly follow up cleanups/fixes to the queue
     changes, but also teardown/removal and misc changes (Christop/Dan/
     Johannes/Sagi/Steve).

   - Two lightnvm fixes for issues that showed up in this window
     (Colin/Wei).

   - Failfast/driver flags inheritance for flush requests (Hannes).

   - The md device put sanitization and fix (Kent).

   - dm bio_set inheritance fix (me).

   - nbd discard granularity fix (Josef).

   - nbd consistency in command printing (Kevin).

   - Loop recursion validation fix (Ted).

   - Partition overlap check (Wang)"

[ .. and now my build is warning-free again thanks to the md fix  - Linus ]

* tag 'for-linus-20180608' of git://git.kernel.dk/linux-block: (22 commits)
  nvme: cleanup double shift issue
  nvme-pci: make CMB SQ mod-param read-only
  nvme-pci: unquiesce dead controller queues
  nvme-pci: remove HMB teardown on reset
  nvme-pci: queue creation fixes
  nvme-pci: remove unnecessary completion doorbell check
  nvme-pci: remove unnecessary nested locking
  nvmet: filter newlines from user input
  nvme-rdma: correctly check for target keyed sgl support
  nvme: don't hold nvmf_transports_rwsem for more than transport lookups
  nvmet: return all zeroed buffer when we can't find an active namespace
  md: Unify mddev destruction paths
  dm: use bioset_init_from_src() to copy bio_set
  block: add bioset_init_from_src() helper
  block: always set partition number to '0' in blk_partition_remap()
  block: pass failfast and driver-specific flags to flush requests
  nbd: set discard_alignment to the granularity
  nbd: Consistently use request pointer in debug messages.
  block: add verifier for cmdline partition
  lightnvm: pblk: fix resource leak of invalid_bitmap
  ...
2018-06-08 13:36:19 -07:00
Linus Torvalds 4a189982e2 Merge branch 'work.aio' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull aio iopriority support from Al Viro:
 "The rest of aio stuff for this cycle - Adam's aio ioprio series"

* 'work.aio' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: aio ioprio use ioprio_check_cap ret val
  fs: aio ioprio add explicit block layer dependence
  fs: iomap dio set bio prio from kiocb prio
  fs: blkdev set bio prio from kiocb prio
  fs: Add aio iopriority support
  fs: Convert kiocb rw_hint from enum to u16
  block: add ioprio_check_cap function
2018-06-08 10:00:20 -07:00
Theodore Ts'o d2ac838e4c loop: add recursion validation to LOOP_CHANGE_FD
Refactor the validation code used in LOOP_SET_FD so it is also used in
LOOP_CHANGE_FD.  Otherwise it is possible to construct a set of loop
devices that all refer to each other.  This can lead to a infinite
loop in starting with "while (is_loop_device(f)) .." in loop_set_fd().

Fix this by refactoring out the validation code and using it for
LOOP_CHANGE_FD as well as LOOP_SET_FD.

Reported-by: syzbot+4349872271ece473a7c91190b68b4bac7c5dbc87@syzkaller.appspotmail.com
Reported-by: syzbot+40bd32c4d9a3cc12a339@syzkaller.appspotmail.com
Reported-by: syzbot+769c54e66f994b041be7@syzkaller.appspotmail.com
Reported-by: syzbot+0a89a9ce473936c57065@syzkaller.appspotmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-06-05 09:08:21 -06:00
Linus Torvalds f459c34538 for-4.18/block-20180603
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Merge tag 'for-4.18/block-20180603' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:

 - clean up how we pass around gfp_t and
   blk_mq_req_flags_t (Christoph)

 - prepare us to defer scheduler attach (Christoph)

 - clean up drivers handling of bounce buffers (Christoph)

 - fix timeout handling corner cases (Christoph/Bart/Keith)

 - bcache fixes (Coly)

 - prep work for bcachefs and some block layer optimizations (Kent).

 - convert users of bio_sets to using embedded structs (Kent).

 - fixes for the BFQ io scheduler (Paolo/Davide/Filippo)

 - lightnvm fixes and improvements (Matias, with contributions from Hans
   and Javier)

 - adding discard throttling to blk-wbt (me)

 - sbitmap blk-mq-tag handling (me/Omar/Ming).

 - remove the sparc jsflash block driver, acked by DaveM.

 - Kyber scheduler improvement from Jianchao, making it more friendly
   wrt merging.

 - conversion of symbolic proc permissions to octal, from Joe Perches.
   Previously the block parts were a mix of both.

 - nbd fixes (Josef and Kevin Vigor)

 - unify how we handle the various kinds of timestamps that the block
   core and utility code uses (Omar)

 - three NVMe pull requests from Keith and Christoph, bringing AEN to
   feature completeness, file backed namespaces, cq/sq lock split, and
   various fixes

 - various little fixes and improvements all over the map

* tag 'for-4.18/block-20180603' of git://git.kernel.dk/linux-block: (196 commits)
  blk-mq: update nr_requests when switching to 'none' scheduler
  block: don't use blocking queue entered for recursive bio submits
  dm-crypt: fix warning in shutdown path
  lightnvm: pblk: take bitmap alloc. out of critical section
  lightnvm: pblk: kick writer on new flush points
  lightnvm: pblk: only try to recover lines with written smeta
  lightnvm: pblk: remove unnecessary bio_get/put
  lightnvm: pblk: add possibility to set write buffer size manually
  lightnvm: fix partial read error path
  lightnvm: proper error handling for pblk_bio_add_pages
  lightnvm: pblk: fix smeta write error path
  lightnvm: pblk: garbage collect lines with failed writes
  lightnvm: pblk: rework write error recovery path
  lightnvm: pblk: remove dead function
  lightnvm: pass flag on graceful teardown to targets
  lightnvm: pblk: check for chunk size before allocating it
  lightnvm: pblk: remove unnecessary argument
  lightnvm: pblk: remove unnecessary indirection
  lightnvm: pblk: return NVM_ error on failed submission
  lightnvm: pblk: warn in case of corrupted write buffer
  ...
2018-06-04 07:58:06 -07:00
Adam Manzanares d9a08a9e61 fs: Add aio iopriority support
This is the per-I/O equivalent of the ioprio_set system call.

When IOCB_FLAG_IOPRIO is set on the iocb aio_flags field, then we set the
newly added kiocb ki_ioprio field to the value in the iocb aio_reqprio field.

This patch depends on block: add ioprio_check_cap function.

Signed-off-by: Adam Manzanares <adam.manzanares@wdc.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2018-05-31 10:50:55 -04:00
Joe Perches 5657a819a8 block drivers/block: Use octal not symbolic permissions
Convert the S_<FOO> symbolic permissions to their octal equivalents as
using octal and not symbolic permissions is preferred by many as more
readable.

see: https://lkml.org/lkml/2016/8/2/1945

Done with automated conversion via:
$ ./scripts/checkpatch.pl -f --types=SYMBOLIC_PERMS --fix-inplace <files...>

Miscellanea:

o Wrapped modified multi-line calls to a single line where appropriate
o Realign modified multi-line calls to open parenthesis

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-24 13:38:59 -06:00
Jeff Layton eedffa28c9 loop: clear wb_err in bd_inode when detaching backing file
When a loop block device encounters a writeback error, that error will
get propagated to the bd_inode's wb_err field. If we then detach the
backing file from it, attach another and fsync it, we'll get back the
writeback error that we had from the previous backing file.

This is a bit of a grey area as POSIX doesn't cover loop devices, but it
is somewhat counterintuitive.

If we detach a backing file from the loopdev while there are still
unreported errors, take it as a sign that we're no longer interested in
the previous file, and clear out the wb_err in the loop blockdev.

Reported-and-Tested-by: Theodore Y. Ts'o <tytso@mit.edu>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-21 12:36:03 -06:00
Tetsuo Handa d3349b6b3c loop: remember whether sysfs_create_group() was done
syzbot is hitting WARN() triggered by memory allocation fault
injection [1] because loop module is calling sysfs_remove_group()
when sysfs_create_group() failed.
Fix this by remembering whether sysfs_create_group() succeeded.

[1] https://syzkaller.appspot.com/bug?id=3f86c0edf75c86d2633aeb9dd69eccc70bc7e90b

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot <syzbot+9f03168400f56df89dbc6f1751f4458fe739ff29@syzkaller.appspotmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Renamed sysfs_ready -> sysfs_inited.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-05-07 15:26:36 -06:00
Jens Axboe f9de14bc7e loop: handle short DIO reads
We ran into an issue with loop and btrfs, where btrfs would complain about
checksum errors. It turns out that is because we don't handle short reads
at all, we just zero fill the remainder. Worse than that, we don't handle
the filling properly, which results in loop trying to advance a single
bio by much more than its size, since it doesn't take chaining into
account.

Handle short reads appropriately, by simply retrying at the new correct
offset. End the remainder of the request with EIO, if we get a 0 read.

Fixes: bc07c10a36 ("block: loop: support DIO & AIO")
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-04-14 22:34:27 -06:00
Jens Axboe 1894e91654 loop: remove cmd->rq member
We can always get at the request from the payload, no need to store
a pointer to it.

Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-04-14 22:34:27 -06:00
Omar Sandoval bdac616db9 loop: fix LOOP_GET_STATUS lock imbalance
Commit 2d1d4c1e59 made loop_get_status() drop lo_ctx_mutex before
returning, but the loop_get_status_old(), loop_get_status64(), and
loop_get_status_compat() wrappers don't call loop_get_status() if the
passed argument is NULL. The callers expect that the lock is dropped, so
make sure we drop it in that case, too.

Reported-by: syzbot+31e8daa8b3fc129e75f2@syzkaller.appspotmail.com
Fixes: 2d1d4c1e59 ("loop: don't call into filesystem while holding lo_ctl_mutex")
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-04-10 08:38:46 -06:00
Tetsuo Handa 1e047eaab3 block/loop: fix deadlock after loop_set_status
syzbot is reporting deadlocks at __blkdev_get() [1].

----------------------------------------
[   92.493919] systemd-udevd   D12696   525      1 0x00000000
[   92.495891] Call Trace:
[   92.501560]  schedule+0x23/0x80
[   92.502923]  schedule_preempt_disabled+0x5/0x10
[   92.504645]  __mutex_lock+0x416/0x9e0
[   92.510760]  __blkdev_get+0x73/0x4f0
[   92.512220]  blkdev_get+0x12e/0x390
[   92.518151]  do_dentry_open+0x1c3/0x2f0
[   92.519815]  path_openat+0x5d9/0xdc0
[   92.521437]  do_filp_open+0x7d/0xf0
[   92.527365]  do_sys_open+0x1b8/0x250
[   92.528831]  do_syscall_64+0x6e/0x270
[   92.530341]  entry_SYSCALL_64_after_hwframe+0x42/0xb7

[   92.931922] 1 lock held by systemd-udevd/525:
[   92.933642]  #0: 00000000a2849e25 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x73/0x4f0
----------------------------------------

The reason of deadlock turned out that wait_event_interruptible() in
blk_queue_enter() got stuck with bdev->bd_mutex held at __blkdev_put()
due to q->mq_freeze_depth == 1.

----------------------------------------
[   92.787172] a.out           S12584   634    633 0x80000002
[   92.789120] Call Trace:
[   92.796693]  schedule+0x23/0x80
[   92.797994]  blk_queue_enter+0x3cb/0x540
[   92.803272]  generic_make_request+0xf0/0x3d0
[   92.807970]  submit_bio+0x67/0x130
[   92.810928]  submit_bh_wbc+0x15e/0x190
[   92.812461]  __block_write_full_page+0x218/0x460
[   92.815792]  __writepage+0x11/0x50
[   92.817209]  write_cache_pages+0x1ae/0x3d0
[   92.825585]  generic_writepages+0x5a/0x90
[   92.831865]  do_writepages+0x43/0xd0
[   92.836972]  __filemap_fdatawrite_range+0xc1/0x100
[   92.838788]  filemap_write_and_wait+0x24/0x70
[   92.840491]  __blkdev_put+0x69/0x1e0
[   92.841949]  blkdev_close+0x16/0x20
[   92.843418]  __fput+0xda/0x1f0
[   92.844740]  task_work_run+0x87/0xb0
[   92.846215]  do_exit+0x2f5/0xba0
[   92.850528]  do_group_exit+0x34/0xb0
[   92.852018]  SyS_exit_group+0xb/0x10
[   92.853449]  do_syscall_64+0x6e/0x270
[   92.854944]  entry_SYSCALL_64_after_hwframe+0x42/0xb7

[   92.943530] 1 lock held by a.out/634:
[   92.945105]  #0: 00000000a2849e25 (&bdev->bd_mutex){+.+.}, at: __blkdev_put+0x3c/0x1e0
----------------------------------------

The reason of q->mq_freeze_depth == 1 turned out that loop_set_status()
forgot to call blk_mq_unfreeze_queue() at error paths for
info->lo_encrypt_type != NULL case.

----------------------------------------
[   37.509497] CPU: 2 PID: 634 Comm: a.out Tainted: G        W        4.16.0+ #457
[   37.513608] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/19/2017
[   37.518832] RIP: 0010:blk_freeze_queue_start+0x17/0x40
[   37.521778] RSP: 0018:ffffb0c2013e7c60 EFLAGS: 00010246
[   37.524078] RAX: 0000000000000000 RBX: ffff8b07b1519798 RCX: 0000000000000000
[   37.527015] RDX: 0000000000000002 RSI: ffffb0c2013e7cc0 RDI: ffff8b07b1519798
[   37.529934] RBP: ffffb0c2013e7cc0 R08: 0000000000000008 R09: 47a189966239b898
[   37.532684] R10: dad78b99b278552f R11: 9332dca72259d5ef R12: ffff8b07acd73678
[   37.535452] R13: 0000000000004c04 R14: 0000000000000000 R15: ffff8b07b841e940
[   37.538186] FS:  00007fede33b9740(0000) GS:ffff8b07b8e80000(0000) knlGS:0000000000000000
[   37.541168] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   37.543590] CR2: 00000000206fdf18 CR3: 0000000130b30006 CR4: 00000000000606e0
[   37.546410] Call Trace:
[   37.547902]  blk_freeze_queue+0x9/0x30
[   37.549968]  loop_set_status+0x67/0x3c0 [loop]
[   37.549975]  loop_set_status64+0x3b/0x70 [loop]
[   37.549986]  lo_ioctl+0x223/0x810 [loop]
[   37.549995]  blkdev_ioctl+0x572/0x980
[   37.550003]  block_ioctl+0x34/0x40
[   37.550006]  do_vfs_ioctl+0xa7/0x6d0
[   37.550017]  ksys_ioctl+0x6b/0x80
[   37.573076]  SyS_ioctl+0x5/0x10
[   37.574831]  do_syscall_64+0x6e/0x270
[   37.576769]  entry_SYSCALL_64_after_hwframe+0x42/0xb7
----------------------------------------

[1] https://syzkaller.appspot.com/bug?id=cd662bc3f6022c0979d01a262c318fab2ee9b56f

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot <bot+48594378e9851eab70bcd6f99327c7db58c5a28a@syzkaller.appspotmail.com>
Fixes: ecdd09597a ("block/loop: fix race between I/O and set_status")
Cc: Ming Lei <tom.leiming@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: stable <stable@vger.kernel.org>
Cc: Jens Axboe <axboe@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-04-10 08:38:46 -06:00
Linus Torvalds 3526dd0c78 for-4.17/block-20180402
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Merge tag 'for-4.17/block-20180402' of git://git.kernel.dk/linux-block

Pull block layer updates from Jens Axboe:
 "It's a pretty quiet round this time, which is nice. This contains:

   - series from Bart, cleaning up the way we set/test/clear atomic
     queue flags.

   - series from Bart, fixing races between gendisk and queue
     registration and removal.

   - set of bcache fixes and improvements from various folks, by way of
     Michael Lyle.

   - set of lightnvm updates from Matias, most of it being the 1.2 to
     2.0 transition.

   - removal of unused DIO flags from Nikolay.

   - blk-mq/sbitmap memory ordering fixes from Omar.

   - divide-by-zero fix for BFQ from Paolo.

   - minor documentation patches from Randy.

   - timeout fix from Tejun.

   - Alpha "can't write a char atomically" fix from Mikulas.

   - set of NVMe fixes by way of Keith.

   - bsg and bsg-lib improvements from Christoph.

   - a few sed-opal fixes from Jonas.

   - cdrom check-disk-change deadlock fix from Maurizio.

   - various little fixes, comment fixes, etc from various folks"

* tag 'for-4.17/block-20180402' of git://git.kernel.dk/linux-block: (139 commits)
  blk-mq: Directly schedule q->timeout_work when aborting a request
  blktrace: fix comment in blktrace_api.h
  lightnvm: remove function name in strings
  lightnvm: pblk: remove some unnecessary NULL checks
  lightnvm: pblk: don't recover unwritten lines
  lightnvm: pblk: implement 2.0 support
  lightnvm: pblk: implement get log report chunk
  lightnvm: pblk: rename ppaf* to addrf*
  lightnvm: pblk: check for supported version
  lightnvm: implement get log report chunk helpers
  lightnvm: make address conversions depend on generic device
  lightnvm: add support for 2.0 address format
  lightnvm: normalize geometry nomenclature
  lightnvm: complete geo structure with maxoc*
  lightnvm: add shorten OCSSD version in geo
  lightnvm: add minor version to generic geometry
  lightnvm: simplify geometry structure
  lightnvm: pblk: refactor init/exit sequences
  lightnvm: Avoid validation of default op value
  lightnvm: centralize permission check for lightnvm ioctl
  ...
2018-04-05 14:27:02 -07:00
Omar Sandoval 3148ffbdb9 loop: use killable lock in ioctls
Even after the previous patch to drop lo_ctl_mutex while calling
vfs_getattr(), there are other cases where we can end up sleeping for a
long time while holding lo_ctl_mutex. Let's avoid the uninterruptible
sleep from the ioctls.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-03-27 14:21:12 -06:00
Omar Sandoval 2d1d4c1e59 loop: don't call into filesystem while holding lo_ctl_mutex
We hit an issue where a loop device on NFS was stuck in
loop_get_status() doing vfs_getattr() after the NFS server died, which
caused a pile-up of uninterruptible processes waiting on lo_ctl_mutex.
There's no reason to hold this lock while we wait on the filesystem;
let's drop it so that other processes can do their thing. We need to
grab a reference on lo_backing_file while we use it, and we can get rid
of the check on lo_device, which has been unnecessary since commit
a34c0ae9ebd6 ("[PATCH] loop: remove the bio remapping capability") in
the linux-history tree.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-03-27 14:21:11 -06:00
Ross Zwisler 1d037577c3 loop: Fix lost writes caused by missing flag
The following commit:

commit aa4d86163e ("block: loop: switch to VFS ITER_BVEC")

replaced __do_lo_send_write(), which used ITER_KVEC iterators, with
lo_write_bvec() which uses ITER_BVEC iterators.  In this change, though,
the WRITE flag was lost:

-       iov_iter_kvec(&from, ITER_KVEC | WRITE, &kvec, 1, len);
+       iov_iter_bvec(&i, ITER_BVEC, bvec, 1, bvec->bv_len);

This flag is necessary for the DAX case because we make decisions based on
whether or not the iterator is a READ or a WRITE in dax_iomap_actor() and
in dax_iomap_rw().

We end up going through this path in configurations where we combine a PMEM
device with 4k sectors, a loopback device and DAX.  The consequence of this
missed flag is that what we intend as a write actually turns into a read in
the DAX code, so no data is ever written.

The very simplest test case is to create a loopback device and try and
write a small string to it, then hexdump a few bytes of the device to see
if the write took.  Without this patch you read back all zeros, with this
you read back the string you wrote.

For XFS this causes us to fail or panic during the following xfstests:

	xfs/074 xfs/078 xfs/216 xfs/217 xfs/250

For ext4 we have a similar issue where writes never happen, but we don't
currently have any xfstests that use loopback and show this issue.

Fix this by restoring the WRITE flag argument to iov_iter_bvec().  This
causes the xfstests to all pass.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@vger.kernel.org
Fixes: commit aa4d86163e ("block: loop: switch to VFS ITER_BVEC")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-03-09 08:36:36 -07:00
Bart Van Assche 8b904b5b6b block: Use blk_queue_flag_*() in drivers instead of queue_flag_*()
This patch has been generated as follows:

for verb in set_unlocked clear_unlocked set clear; do
  replace-in-files queue_flag_${verb} blk_queue_flag_${verb%_unlocked} \
    $(git grep -lw queue_flag_${verb} drivers block/bsg*)
done

Except for protecting all queue flag changes with the queue lock
this patch does not change any functionality.

Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-03-08 14:13:48 -07:00
Bart Van Assche 0fa8ebdd42 block/loop: Delete gendisk before cleaning up the request queue
Remove the disk, partition and bdi sysfs attributes before cleaning up
the request queue associated with the disk.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-02-28 12:23:35 -07:00
Jan Kara 3079c22ea8 genhd: Rename get_disk() to get_disk_and_module()
Rename get_disk() to get_disk_and_module() to make sure what the
function does. It's not a great name but at least it is now clear that
put_disk() is not it's counterpart.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-02-26 09:48:42 -07:00