linux-toradex.git/drivers/md/dm-integrity.c, branch v4.16

dm integrity: don't store cipher request on the stack

2018-01-17T14:08:57+00:00

Some asynchronous cipher implementations may use DMA.  The stack may
be mapped in the vmalloc area that doesn't support DMA.  Therefore,
the cipher request and initialization vector shouldn't be on the
stack.

Fix this by allocating the request and iv with kmalloc.

Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer

md: Convert timers to use timer_setup()

2017-11-15T03:11:57+00:00

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Cc: Kent Overstreet 
Cc: Shaohua Li 
Cc: Alasdair Kergon 
Cc: Mike Snitzer 
Cc: dm-devel@redhat.com
Cc: linux-bcache@vger.kernel.org
Cc: linux-raid@vger.kernel.org
Signed-off-by: Kees Cook 
Reviewed-by: Michael Lyle 
Reviewed-by: Mike Snitzer 
Signed-off-by: Jens Axboe

Merge tag 'for-4.15/dm' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

2017-11-14T23:50:56+00:00

Pull device mapper updates from Mike Snitzer:

 - a few conversions from atomic_t to ref_count_t

 - a DM core fix for a race during device destruction that could result
   in a BUG_ON

 - a stable@ fix for a DM cache race condition that could lead to data
   corruption when operating in writeback mode (writethrough is default)

 - various DM cache cleanups and improvements

 - add DAX support to the DM log-writes target

 - a fix for the DM zoned target's ability to deal with the last zone of
   the drive being smaller than all others

 - a stable@ DM crypt and DM integrity fix for a negative check that was
   to restrictive (prevented slab debug with XFS ontop of DM crypt from
   working)

 - a DM raid target fix for a panic that can occur when forcing a raid
   to sync

* tag 'for-4.15/dm' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (25 commits)
  dm cache: lift common migration preparation code to alloc_migration()
  dm cache: remove usused deferred_cells member from struct cache
  dm cache policy smq: allocate cache blocks in order
  dm cache policy smq: change max background work from 10240 to 4096 blocks
  dm cache background tracker: limit amount of background work that may be issued at once
  dm cache policy smq: take origin idle status into account when queuing writebacks
  dm cache policy smq: handle races with queuing background_work
  dm raid: fix panic when attempting to force a raid to sync
  dm integrity: allow unaligned bv_offset
  dm crypt: allow unaligned bv_offset
  dm: small cleanup in dm_get_md()
  dm: fix race between dm_get_from_kobject() and __dm_destroy()
  dm: allocate struct mapped_device with kvzalloc
  dm zoned: ignore last smaller runt zone
  dm space map metadata: use ARRAY_SIZE
  dm log writes: add support for DAX
  dm log writes: add support for inline data buffers
  dm cache: simplify get_per_bio_data() by removing data_size argument
  dm cache: remove all obsolete writethrough-specific code
  dm cache: submit writethrough writes in parallel to origin and cache
  ...

dm integrity: allow unaligned bv_offset

2017-11-10T20:44:59+00:00

When slub_debug is enabled kmalloc returns unaligned memory. XFS uses
this unaligned memory for its buffers (if an unaligned buffer crosses a
page, XFS frees it and allocates a full page instead - see the function
xfs_buf_allocate_memory).

dm-integrity checks if bv_offset is aligned on page size and this check
fail with slub_debug and XFS.

Fix this bug by removing the bv_offset check, leaving only the check for
bv_len.

Fixes: 7eada909bfd7 ("dm: add integrity target")
Cc: stable@vger.kernel.org # v4.12+
Reported-by: Bruno Prémont 
Reviewed-by: Milan Broz 
Signed-off-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer

locking/atomics, dm-integrity: Convert ACCESS_ONCE() to READ_ONCE()/WRITE_ONCE()

2017-10-25T09:00:55+00:00

For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't currently harmful.

However, for some features it is necessary to instrument reads and
writes separately, which is not possible with ACCESS_ONCE(). This
distinction is critical to correct operation.

It's possible to transform the bulk of kernel code using the Coccinelle
script below. However, this doesn't pick up some uses, including those
in dm-integrity.c. As a preparatory step, this patch converts the driver
to use {READ,WRITE}_ONCE() consistently.

At the same time, this patch adds the missing include of
 necessary for the {READ,WRITE}_ONCE() definitions.

----
virtual patch

@ depends on patch @
expression E1, E2;
@@

- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)

@ depends on patch @
expression E;
@@

- ACCESS_ONCE(E)
+ READ_ONCE(E)
----

Signed-off-by: Mark Rutland 
Signed-off-by: Paul E. McKenney 
Cc: Linus Torvalds 
Cc: Mike Snitzer 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-1-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar

Merge tag 'for-4.14/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

2017-09-14T20:43:16+00:00

Pull device mapper updates from Mike Snitzer:

 - Some request-based DM core and DM multipath fixes and cleanups

 - Constify a few variables in DM core and DM integrity

 - Add bufio optimization and checksum failure accounting to DM
   integrity

 - Fix DM integrity to avoid checking integrity of failed reads

 - Fix DM integrity to use init_completion

 - A couple DM log-writes target fixes

 - Simplify DAX flushing by eliminating the unnecessary flush
   abstraction that was stood up for DM's use.

* tag 'for-4.14/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dax: remove the pmem_dax_ops->flush abstraction
  dm integrity: use init_completion instead of COMPLETION_INITIALIZER_ONSTACK
  dm integrity: make blk_integrity_profile structure const
  dm integrity: do not check integrity for failed read operations
  dm log writes: fix >512b sectorsize support
  dm log writes: don't use all the cpu while waiting to log blocks
  dm ioctl: constify ioctl lookup table
  dm: constify argument arrays
  dm integrity: count and display checksum failures
  dm integrity: optimize writing dm-bufio buffers that are partially changed
  dm rq: do not update rq partially in each ending bio
  dm rq: make dm-sq requeuing behavior consistent with dm-mq behavior
  dm mpath: complain about unsupported __multipath_map_bio() return values
  dm mpath: avoid that building with W=1 causes gcc 7 to complain about fall-through

dm integrity: use init_completion instead of COMPLETION_INITIALIZER_ONSTACK

2017-09-11T15:00:54+00:00

The new lockdep support for completions causeed the stack usage
in dm-integrity to explode, in case of write_journal from 504 bytes
to 1120 (using arm gcc-7.1.1):

drivers/md/dm-integrity.c: In function 'write_journal':
drivers/md/dm-integrity.c:827:1: error: the frame size of 1120 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]

The problem is that not only the size of 'struct completion' grows
significantly, but we end up having multiple copies of it on the stack
when we assign it from a local variable after the initial declaration.

COMPLETION_INITIALIZER_ONSTACK() is the right thing to use when we
want to declare and initialize a completion on the stack. However,
this driver doesn't do that and instead initializes the completion
just before it is used.

In this case, init_completion() does the same thing more efficiently,
and drops the stack usage for the function above down to 496 bytes.
While the other functions in this file are not bad enough to cause
a warning, they benefit equally from the change, so I do the change
across the entire file. In the one place where we reuse a completion,
I picked the cheaper reinit_completion() over init_completion().

Fixes: cd8084f91c02 ("locking/lockdep: Apply crossrelease to completions")
Signed-off-by: Arnd Bergmann 
Acked-by: Mikulas Patocka 
Acked-by: Mike Snitzer 
Signed-off-by: Mike Snitzer

dm integrity: make blk_integrity_profile structure const

2017-09-11T15:00:53+00:00

Make this structure const as it is only stored in the profile field of a
blk_integrity structure. This field is of type const, so make structure
as const.

Signed-off-by: Bhumika Goyal 
Signed-off-by: Mike Snitzer

dm integrity: do not check integrity for failed read operations

2017-09-11T14:07:34+00:00

Even though read operations fail, dm_integrity_map_continue() calls
integrity_metadata() to check integrity.  In this case, just complete
these.

This also makes it so read I/O errors do not generate integrity warnings
in the kernel log.

Cc: stable@vger.kernel.org
Signed-off-by: Hyunchul Lee 
Acked-by: Milan Broz 
Acked-by: Mikulas Patocka 
Signed-off-by: Mike Snitzer

dm: constify argument arrays

2017-08-28T15:47:18+00:00

The arrays of 'struct dm_arg' are never modified by the device-mapper
core, so constify them so that they are placed in .rodata.

(Exception: the args array in dm-raid cannot be constified because it is
allocated on the stack and modified.)

Signed-off-by: Eric Biggers 
Signed-off-by: Mike Snitzer