gcc-6.0 found an ancient bug in the paride driver, which had a
"module_param(verbose, bool, 0);" since before 2.6.12, but actually uses
it to accept '0', '1' or '2' as arguments:

  drivers/block/paride/pd.c: In function 'pd_init_dev_parms':
  drivers/block/paride/pd.c:298:29: warning: comparison of constant '1' with boolean expression is always false [-Wbool-compare]
   #define DBMSG(msg) ((verbose>1)?(msg):NULL)

In 2012, Rusty did a cleanup patch that also changed the type of the
variable to 'bool', which introduced what is now a gcc warning.

This changes the type back to 'int' and adapts the module_param() line
instead, so it should work as documented in case anyone ever cares about
running the ancient driver with debugging.

Fixes: 90ab5ee9 ("module_param: make bool parameters really bool (drivers & misc)")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Rusty Russell <rusty@rustcorp.com.au>
Cc: Tim Waugh <tim@cyberelk.net>
Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Cc: Jens Axboe <axboe@fb.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit d4366414 ("cpqarray: remove it from the kernel") removes the
Kconfig option BLK_CPQ_DA and cpqarray.

Remove the dead build rule in the Makefile.
Signed-off-by: NValentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Avoid that discard requests with size => PAGE_SIZE fail with
-EIO. Refuse discard requests if the discard size is not a
multiple of the page size.

Fixes: 2dbe5495 ("brd: Refuse improperly aligned discard requests")
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: NJan Kara <jack@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Robert Elliot <elliott@hp.com>
Cc: stable <stable@vger.kernel.org> # v4.4+
Signed-off-by: NJens Axboe <axboe@fb.com>

We disabled the ability to enable this driver back in October of 2013,
we should be able to safely remove it at this point. The initial goal
was to remove it in 3.15, so now is the time.
Signed-off-by: NJens Axboe <axboe@fb.com>

The do_div() macro now checks its arguments for the correct type,
and refuses anything other than u64, so we get a warning about
nbd_ioctl passing in an loff_t:

drivers/block/nbd.c: In function '__nbd_ioctl':
drivers/block/nbd.c:757:77: error: comparison of distinct pointer types lacks a cast [-Werror]

This changes the nbd code to use div_s64() instead, which takes
a signed argument.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Fixes: 37091fdd ("nbd: Create size change events for userspace")
Signed-off-by: NJens Axboe <axboe@fb.com>

We always return BLK_EH_RESET_TIMER, so no point in storing that in
an integer.
Signed-off-by: NJens Axboe <axboe@fb.com>

The processes names are truncated to 17, while we had the length
of the process as name 20 - which meant that while we filled
it out with various details - the last 3 characters (which had
the queue number) never surfaced to the user-space.

To simplify this and be able to fit the device name, domain id,
and the queue number we remove the 'blkback' from the name.

Prior to this patch the device name is "blkback.<domid>.<name>"
for example: blkback.8.xvda, blkback.11.hda.

With the multiqueue block backend we add "-%d" for the queue.
But sadly this is already way past the limit so it gets stripped.

Possible solution had been identified by Ian:
http://lists.xenproject.org/archives/html/xen-devel/2015-05/msg03516.html

  "
  If you are pressed for space then the "xvd" is probably a bit redundant
  in a string which starts blkbk.

  The guest may not even call the device xvdN (iirc BSD has another
  prefix) any how, so having blkback say so seems of limited use anyway.

  Since this seems to not include a partition number how does this work in
  the split partition scheme? (i.e. one where the guest is given xvda1 and
  xvda2 rather than xvda with a partition table)

[It will be 'blkback.8.xvda1', and 'blkback.11.xvda2']

  Perhaps something derived from one of the schemes in
  http://xenbits.xen.org/docs/unstable/misc/vbd-interface.txt might be a
  better fit?

After a bit of discussion (see
http://lists.xenproject.org/archives/html/xen-devel/2015-12/msg01588.html)
we settled on dropping the "blback" part.

This will make it possible to have the <domid>.<name>-<queue>:

 [1.xvda-0]
 [1.xvda-1]

And we enough space to make it go up to:

 [32100.xvdfg9-5]
Acked-by: NRoger Pau Monné <roger.pau@citrix.com>
Reported-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

There's no reason to defer this until the connect phase, and in fact
there are frontend implementations expecting this to be available
earlier. Move it into the probe function.
Acked-by: NRoger Pau Monné <roger.pau@citrix.com>
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Cc: Bob Liu <bob.liu@oracle.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

"max" is rather ambiguous and carries pretty little meaning, the more
that there are also "max_queues" and "max_ring_page_order". Make this
"max_indirect_segments" instead, and at once change the type from int
to uint (to match the respective variable's type).
Acked-by: NRoger Pau Monné <roger.pau@citrix.com>
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

Fail all pending requests after surprise removal of a drive.
Signed-off-by: NVignesh Gunasekaran <vgunasekaran@micron.com>
Signed-off-by: NSelvan Mani <smani@micron.com>
Signed-off-by: NAsai Thambi S P <asamymuthupa@micron.com>
Cc: stable@vger.kernel.org
Signed-off-by: NJens Axboe <axboe@fb.com>

Added timeout handler. Replaced blk_mq_end_request() with
blk_mq_complete_request() to avoid double completion of a request.
Signed-off-by: NSelvan Mani <smani@micron.com>
Signed-off-by: NRajesh Kumar Sambandam <rsambandam@micron.com>
Signed-off-by: NAsai Thambi S P <asamymuthupa@micron.com>
Cc: stable@vger.kernel.org
Signed-off-by: NJens Axboe <axboe@fb.com>

Allow device initialization to finish gracefully when it is in
FTL rebuild failure state. Also, recover device out of this state
after successfully secure erasing it.
Signed-off-by: NSelvan Mani <smani@micron.com>
Signed-off-by: NVignesh Gunasekaran <vgunasekaran@micron.com>
Signed-off-by: NAsai Thambi S P <asamymuthupa@micron.com>
Cc: stable@vger.kernel.org
Signed-off-by: NJens Axboe <axboe@fb.com>

Flush inflight IOs using fsync_bdev() when the device is safely
removed. Also, block further IOs in device open function.
Signed-off-by: NSelvan Mani <smani@micron.com>
Signed-off-by: NRajesh Kumar Sambandam <rsambandam@micron.com>
Signed-off-by: NAsai Thambi S P <asamymuthupa@micron.com>
Cc: stable@vger.kernel.org
Signed-off-by: NJens Axboe <axboe@fb.com>

When FTL rebuild is in progress, alloc_disk() initializes the disk
but device node will be created by add_disk() only after successful
completion of FTL rebuild. So, skip deletion of device node in
removal path when FTL rebuild is in progress.
Signed-off-by: NSelvan Mani <smani@micron.com>
Signed-off-by: NAsai Thambi S P <asamymuthupa@micron.com>
Cc: stable@vger.kernel.org
Signed-off-by: NJens Axboe <axboe@fb.com>

Prevent standby immediate command from being issued in remove,
suspend and shutdown paths, while drive is in FTL rebuild process.
Signed-off-by: NSelvan Mani <smani@micron.com>
Signed-off-by: NVignesh Gunasekaran <vgunasekaran@micron.com>
Signed-off-by: NAsai Thambi S P <asamymuthupa@micron.com>
Cc: stable@vger.kernel.org
Signed-off-by: NJens Axboe <axboe@fb.com>

Print exact time when an internal command is interrupted.
Signed-off-by: NSelvan Mani <smani@micron.com>
Signed-off-by: NRajesh Kumar Sambandam <rsambandam@micron.com>
Signed-off-by: NAsai Thambi S P <asamymuthupa@micron.com>
Cc: stable@vger.kernel.org
Signed-off-by: NJens Axboe <axboe@fb.com>

Remove setting and clearing MTIP_PF_EH_ACTIVE_BIT flag in
mtip_handle_tfe() as they are redundant. Also avoid waking
up service thread from mtip_handle_tfe() because it is
already woken up in case of taskfile error.
Signed-off-by: NSelvan Mani <smani@micron.com>
Signed-off-by: NRajesh Kumar Sambandam <rsambandam@micron.com>
Signed-off-by: NAsai Thambi S P <asamymuthupa@micron.com>
Cc: stable@vger.kernel.org
Signed-off-by: NJens Axboe <axboe@fb.com>

Service thread does not detect the need for taskfile error hanlding. Fixed the
flag condition to process taskfile error.
Signed-off-by: NSelvan Mani <smani@micron.com>
Signed-off-by: NAsai Thambi S P <asamymuthupa@micron.com>
Cc: stable@vger.kernel.org
Signed-off-by: NJens Axboe <axboe@fb.com>

The userspace needs to know when nbd devices are ready for use.
Currently no events are created for the userspace which doesn't work for
systemd.

See the discussion here: https://github.com/systemd/systemd/pull/358

This patch uses a central point to setup the nbd-internal sizes. A ioctl
to set a size does not lead to a visible size change. The size of the
block device will be kept at 0 until nbd is connected. As soon as it
connects, the size will be changed to the real value and a uevent is
created. When disconnecting, the blockdevice is set to 0 size and
another uevent is generated.
Signed-off-by: NMarkus Pargmann <mpa@pengutronix.de>

If the LightNVM subsystem is not compiled into the kernel, and the
null_blk device driver requests lightnvm to be initialized. The call to
nvm_register fails and the null_add_dev function cleans up the
initialization. However, at this point the null block device has
already been added to the nullb_list and thus a second cleanup will
occur when the function has returned, that leads to a double call to
blk_cleanup_queue.
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

In case /dev/fdX is open with O_NDELAY / O_NONBLOCK, floppy_open() immediately
succeeds, without performing any further media / controller preparations.
That's "correct" wrt. the NODELAY flag, but is hardly correct wrt. the rest
of the floppy driver, that is not really O_NONBLOCK ready, at all. Therefore
it's not too surprising, that subsequent attempts to work with the
filedescriptor produce bad results. Namely, syzkaller tool has been able
to livelock mmap() on the returned fd to keep waiting on the page unlock
bit forever.

Quite frankly, I have trouble defining what non-blocking behavior would be for
floppies. Is waiting ages for the driver to actually succeed reading a sector
blocking operation? Is waiting for drive motor to start blocking operation? How
about in case of virtualized floppies?

One option would be returning EWOULDBLOCK in case O_NDLEAY / O_NONBLOCK is
being passed to open(). That has a theoretical potential of breaking some
arcane and archaic userspace though.

Let's take a more conservative aproach, and accept the O_NDLEAY flag, and let
the driver behave as usual.

While at it, clean up a bit handling of !(mode & (FMODE_READ|FMODE_WRITE))
case and return EINVAL instead of succeeding as well.

Spotted by syzkaller tool.
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Tested-by: NDmitry Vyukov <dvyukov@google.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Make the "Attempted send on closed socket" error messages generated in
nbd_request_handler() ratelimited.

When the nbd socket is shutdown, the nbd_request_handler() function emits
an error message for every request remaining in its queue.  If the queue
is large, this will spam a large amount of messages to the log.  There's
no need for a separate error message for each request, so this patch
ratelimits it.

In the specific case this was found, the system was virtual and the error
messages were logged to the serial port, which overwhelmed it.

Fixes: 4d48a542 ("nbd: fix I/O hang on disconnected nbds")
Signed-off-by: NDan Streetman <dan.streetman@canonical.com>
Signed-off-by: NMarkus Pargmann <mpa@pengutronix.de>

nbd changes properties of the blockdevice depending on flags that were
received. This patch moves this flag parsing into a separate function
nbd_parse_flags().
Signed-off-by: NMarkus Pargmann <mpa@pengutronix.de>

Group all variables that are reset after a disconnect into reset
functions. This patch adds two of these functions, nbd_reset() and
nbd_bdev_reset().
Signed-off-by: NMarkus Pargmann <mpa@pengutronix.de>

It may be useful to know in the client that a connection timed out. The
current code returns success for a timeout.

This patch reports the error code -ETIMEDOUT for a timeout.
Signed-off-by: NMarkus Pargmann <mpa@pengutronix.de>

As discussed on the mailing list, the usage of signals for timeout
handling has a lot of potential issues. The nbd driver used for some
time signals for timeouts. These signals where able to get the threads
out of the blocking socket operations.

This patch removes all signal usage and uses a socket shutdown instead.
The socket descriptor itself is cleared later when the whole nbd device
is closed.

The tasks_lock is removed as we do not depend on this anymore. Instead
a new lock for the socket is introduced so we can safely work with the
socket in the timeout handler outside of the two main threads.

Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: NMarkus Pargmann <mpa@pengutronix.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>

System block allows the device to initialize with its configured media
manager. The system blocks is written to disk, and read again when media
manager is determined. For this to work, the backend must store the
data. Device drivers, such as null_blk, does not have any backend
storage. This patch allows the media manager to be initialized without a
storage backend.

It also fix incorrect configuration of capabilities in null_blk, as it
does not support get/set bad block interface.
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

Static checker complains about the implemented error handling. It is
indeed wrong. We don't care about the return values of created debugfs
files.

We only have to check the return values of created dirs for NULL
pointer. If we use a null pointer as parent directory for files, this
may lead to debugfs files in wrong places.
Signed-off-by: NMarkus Pargmann <mpa@pengutronix.de>

floppy_revalidate() doesn't perform any error handling on lock_fdc()
result. lock_fdc() might actually be interrupted by a signal (it waits for
fdc becoming non-busy interruptibly). In such case, floppy_revalidate()
proceeds as if it had claimed the lock, but it fact it doesn't.

In case of multiple threads trying to open("/dev/fdX"), this leads to
serious corruptions all over the place, because all of a sudden there is
no critical section protection (that'd otherwise be guaranteed by locked
fd) whatsoever.

While at this, fix the fact that the 'interruptible' parameter to
lock_fdc() doesn't make any sense whatsoever, because we always wait
interruptibly anyway.

Most of the lock_fdc() callsites do properly handle error (and propagate
EINTR), but floppy_revalidate() and floppy_check_events() don't. Fix this.

Spotted by 'syzkaller' tool.
Reported-by: NDmitry Vyukov <dvyukov@google.com>
Tested-by: NDmitry Vyukov <dvyukov@google.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Need to reallocate ring info in the resume path, because info->rinfo was freed
in blkif_free(). And 'multi-queue-max-queues' backend reports may have been
changed.
Signed-off-by: NBob Liu <bob.liu@oracle.com>
Reported-and-Tested-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

This patch replaces uses of the long obsolete hash interface with
either shash (for non-SG users) or ahash.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch replaces uses of blkcipher with the new skcipher
interface.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

There are many locations that do

  if (memory_was_allocated_by_vmalloc)
    vfree(ptr);
  else
    kfree(ptr);

but kvfree() can handle both kmalloc()ed memory and vmalloc()ed memory
using is_vmalloc_addr().  Unless callers have special reasons, we can
replace this branch with kvfree().  Please check and reply if you found
problems.
Signed-off-by: NTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: NMichal Hocko <mhocko@suse.com>
Acked-by: NJan Kara <jack@suse.com>
Acked-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Reviewed-by: NAndreas Dilger <andreas.dilger@intel.com>
Acked-by: N"Rafael J. Wysocki" <rjw@rjwysocki.net>
Acked-by: NDavid Rientjes <rientjes@google.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Oleg Drokin <oleg.drokin@intel.com>
Cc: Boris Petkov <bp@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).

Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

The rbd_dev_destroy() function tests whether its argument is NULL
and then returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

For the purpose of communicating the optional presence of a 'struct
page' for the pfn returned from ->direct_access(), introduce a type that
encapsulates a page-frame-number plus flags.  These flags contain the
historical "page_link" encoding for a scatterlist entry, but can also
denote "device memory".  Where "device memory" is a set of pfns that are
not part of the kernel's linear mapping by default, but are accessed via
the same memory controller as ram.

The motivation for this new type is large capacity persistent memory
that needs struct page entries in the 'memmap' to support 3rd party DMA
(i.e.  O_DIRECT I/O with a persistent memory source/target).  However,
we also need it in support of maintaining a list of mapped inodes which
need to be unmapped at driver teardown or freeze_bdev() time.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Hansen <dave@sr71.net>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The use of idr_remove() is forbidden in the callback functions of
idr_for_each().  It is therefore unsafe to call idr_remove in
zram_remove().

This patch moves the call to idr_remove() from zram_remove() to
hot_remove_store().  In the detroy_devices() path, idrs are removed by
idr_destroy().  This solves an use-after-free detected by KASan.

[akpm@linux-foundation.org: fix coding stype, per Sergey]
Signed-off-by: NJerome Marchand <jmarchan@redhat.com>
Acked-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: <stable@vger.kernel.org>	[4.2+]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Do not __GFP_ZERO allocated zcomp ->private pages.  We keep allocated
streams around and use them for read/write requests, so we supply a
zeroed out ->private to compression algorithm as a scratch buffer only
once -- the first time we use that stream.  For the rest of IO requests
served by this stream ->private usually contains some temporarily data
from the previous requests.
Signed-off-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Acked-by: NMinchan Kim <minchan@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Each zcomp backend uses own gfp flag but it's pointless because the
context they could be called is driven by upper layer(ie, zcomp
frontend).  As well, zcomp frondend could call them in different
context.  One context(ie, zram init part) is it should be better to make
sure successful allocation other context(ie, further stream allocation
part for accelarating I/O speed) is just optional so let's pass gfp down
from driver (ie, zcomp frontend) like normal MM convention.

[sergey.senozhatsky@gmail.com: add missing __vmalloc zero and highmem gfps]
Signed-off-by: NMinchan Kim <minchan@kernel.org>
Signed-off-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When we're using LZ4 multi compression streams for zram swap, we found
out page allocation failure message in system running test.  That was
not only once, but a few(2 - 5 times per test).  Also, some failure
cases were continually occurring to try allocation order 3.

In order to make parallel compression private data, we should call
kzalloc() with order 2/3 in runtime(lzo/lz4).  But if there is no order
2/3 size memory to allocate in that time, page allocation fails.  This
patch makes to use vmalloc() as fallback of kmalloc(), this prevents
page alloc failure warning.

After using this, we never found warning message in running test, also
It could reduce process startup latency about 60-120ms in each case.

For reference a call trace :

    Binder_1: page allocation failure: order:3, mode:0x10c0d0
    CPU: 0 PID: 424 Comm: Binder_1 Tainted: GW 3.10.49-perf-g991d02b-dirty #20
    Call trace:
      dump_backtrace+0x0/0x270
      show_stack+0x10/0x1c
      dump_stack+0x1c/0x28
      warn_alloc_failed+0xfc/0x11c
      __alloc_pages_nodemask+0x724/0x7f0
      __get_free_pages+0x14/0x5c
      kmalloc_order_trace+0x38/0xd8
      zcomp_lz4_create+0x2c/0x38
      zcomp_strm_alloc+0x34/0x78
      zcomp_strm_multi_find+0x124/0x1ec
      zcomp_strm_find+0xc/0x18
      zram_bvec_rw+0x2fc/0x780
      zram_make_request+0x25c/0x2d4
      generic_make_request+0x80/0xbc
      submit_bio+0xa4/0x15c
      __swap_writepage+0x218/0x230
      swap_writepage+0x3c/0x4c
      shrink_page_list+0x51c/0x8d0
      shrink_inactive_list+0x3f8/0x60c
      shrink_lruvec+0x33c/0x4cc
      shrink_zone+0x3c/0x100
      try_to_free_pages+0x2b8/0x54c
      __alloc_pages_nodemask+0x514/0x7f0
      __get_free_pages+0x14/0x5c
      proc_info_read+0x50/0xe4
      vfs_read+0xa0/0x12c
      SyS_read+0x44/0x74
    DMA: 3397*4kB (MC) 26*8kB (RC) 0*16kB 0*32kB 0*64kB 0*128kB 0*256kB
         0*512kB 0*1024kB 0*2048kB 0*4096kB = 13796kB

[minchan@kernel.org: change vmalloc gfp and adding comment about gfp]
[sergey.senozhatsky@gmail.com: tweak comments and styles]
Signed-off-by: NKyeongdon Kim <kyeongdon.kim@lge.com>
Signed-off-by: NMinchan Kim <minchan@kernel.org>
Acked-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>