/sys/class/scsi_disk/0:2:0:0/allow_restart can be changed to 0
unexpectedly by writing an invalid string such as the following:

echo asdf > /sys/class/scsi_disk/0:2:0:0/allow_restart
Signed-off-by: Nweiping zhang <zhangweiping@didichuxing.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Reporting a maximum number of blocks that is not aligned on the device
physical size would cause a large write same request to be split into
physically unaligned chunks by __blkdev_issue_write_zeroes() and
__blkdev_issue_write_same(), even if the caller of these functions took
care to align its request to physical sectors.

Make sure the maximum reported is aligned to the device physical block
size. This is only an optional optimization for regular disks, but this
is mandatory to avoid failure of large write same requests directed at
sequential write required zones of host-managed ZBC disks.

[mkp: tweaked commit message]
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

gd->minors has been set when call alloc_disk() in sd_probe.
Signed-off-by: Nweiping zhang <zhangweiping@didichuxing.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch avoids that gcc reports the following warning when
building with W=1:

drivers/scsi/sd.c:315:10: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits]
  if (val >= 0 && val <= T10_PI_TYPE3_PROTECTION)
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch avoids that smatch reports the following:

drivers/scsi/sd.c:3540: sd_suspend_common() warn: inconsistent indenting
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Before scsi_prep_fn() calls the ULP .init_command() callback
function it stores the SCSI command pointer in request.special.
This means that the SCpnt = rq->special assignments in the sd
and sr drivers assign a pointer to itself. Hence convert these
two assignment statements into warning statements.
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Releasing a zone write lock only when the write commnand that acquired
the lock completes can cause deadlocks due to potential command
reordering if the lock owning request is requeued and not executed. This
problem exists only with the scsi-mq path as, unlike the legacy path,
requests are moved out of the dispatch queue before being prepared and
so before locking a zone for a write command.

Since sd_uninit_cmnd() is now always called when a request is requeued,
call sd_zbc_write_unlock_zone() from that function for write requests
that acquired a zone lock instead of from sd_done(). Acquisition of a zone
lock by a write command is indicated using the new command
flag SCMD_ZONE_WRITE_LOCK.
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBart Van Assche <Bart.VanAssche@wdc.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Just wire up the generic TCG OPAL infrastructure to the SCSI disk driver
and the Security In/Out commands.

Note that I don't know of any actual SCSI disks that do support TCG OPAL,
but this is required to support ATA disks through libata.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NTejun Heo <tj@kernel.org>

Avoid unnecessary snprintf() when formatting variables for display in
sysfs and switch to sysfs_match_string() for validating user input.
Reviewed-by: NBart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Serializing SCSI device state changes avoids that two state changes can
occur concurrently, e.g. the state changes in scsi_target_block() and
__scsi_remove_device(). This serialization is essential to make patch
"Make __scsi_remove_device go straight from BLOCKED to DEL" work
reliably.

Enable this mechanism for all scsi_target_*block() callers but not for
the scsi_internal_device_unblock() calls from the mpt3sas driver because
that driver can call scsi_internal_device_unblock() from atomic context.
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Some external hard drives don't support the sync command even though the
hard drive has write cache enabled. In this case, upon suspend request,
sync cache failures are ignored if the error code in the sense header is
ILLEGAL_REQUEST. There's not much we can do for these drives, so we
shouldn't fail to suspend for this error case. The drive may stay
powered if that's the setup for the port it's plugged into.
Signed-off-by: NDerek Basehore <dbasehore@chromium.org>
Signed-off-by: NThierry Escande <thierry.escande@collabora.com>
Reviewed-by: NEwan D. Milne <emilne@redhat.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

For a zoned block device, sd_zbc_complete() handles zone write unlock on
completion of a REQ_OP_WRITE_ZEROES command but the zone write locking
is missing from sd_setup_write_zeroes_cmnd(). This patch fixes this
problem by locking the target zone of a REQ_OP_WRITE_ZEROES request.
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

scsi_io_init() may fail, leaving a zone of a zoned block device locked.
Fix this by properly unlocking the write same request target zone if
scsi_io_init() fails.
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Rename sd_zbc_setup_write_cmnd() to sd_zbc_write_lock_zone() to be clear
about what the function actually does. To be consistent, also rename
sd_zbc_cancel_write_cmnd() to sd_zbc_write_unlock_zone().

No functional change is introduced by this patch.
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: NBart Van Assche <Bart.VanAssche@sandisk.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Use a switch for the sense key, and remove two pointless variables that
are only used once.

[mkp: Added UNMAP comment and removed good_bytes based on comment from
Damien]
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Re-shuffle the code to be more efficient by not initializing variables
upfront (i.e. do it only when necessary).  Also replace the do_div calls
with calls to sectors_to_logical().

No functional change is introduced by this patch.

[mkp: bytes_to_logical()]
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Fix argument names and description of function documentation comments.
No functional change is introduced by this patch.

[mkp: verbify]
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Separating discards and zeroout operations allows us to remove the LBPRZ
block zeroing constraints from discards and honor the device preferences
for UNMAP commands.

If supported by the device, we'll also choose UNMAP over one of the
WRITE SAME variants for discards.
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Now that zeroout and discards are distinct operations we need to
separate the policy of choosing the appropriate command. Create a
zeroing_mode which can be one of:

write:			Zeroout assist not present, use regular WRITE
writesame:		Allow WRITE SAME(10/16) with a zeroed payload
writesame_16_unmap:	Allow WRITE SAME(16) with UNMAP
writesame_10_unmap:	Allow WRITE SAME(10) with UNMAP

The last two are conditional on the device being thin provisioned with
LBPRZ=1 and LBPWS=1 or LBPWS10=1 respectively.

Whether to set the UNMAP bit or not depends on the REQ_NOUNMAP flag. And
if none of the _unmap variants are supported, regular WRITE SAME will be
used if the device supports it.

The zeroout_mode is exported in sysfs and the detected mode for a given
device can be overridden using the string constants above.

With this change in place we can now issue WRITE SAME(16) with UNMAP set
for block zeroing applications that require hard guarantees and
logical_block_size granularity. And at the same time use the UNMAP
command with the device's preferred granulary and alignment for discard
operations.
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Now that we use the proper REQ_OP_WRITE_ZEROES operation everywhere we can
kill this hack.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Try to use a write same with unmap bit variant if the device supports it
and the caller allows for it.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Split sd_setup_discard_cmnd into one function per provisioning type.  While
this creates some very slight duplication of boilerplate code it keeps the
code modular for additions of new provisioning types, and for reusing the
write same functions for the upcoming scsi implementation of the Write Zeroes
operation.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

We previously made sure that the reported disk capacity was less than
0xffffffff blocks when the kernel was not compiled with large sector_t
support (CONFIG_LBDAF). However, this check assumed that the capacity
was reported in units of 512 bytes.

Add a sanity check function to ensure that we only enable disks if the
entire reported capacity can be expressed in terms of sector_t.

Cc: <stable@vger.kernel.org>
Reported-by: NSteve Magnani <steve.magnani@digidescorp.com>
Cc: Bart Van Assche <Bart.VanAssche@sandisk.com>
Reviewed-by: NBart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

If device reports a small max_xfer_blocks and a zero opt_xfer_blocks, we
end up using BLK_DEF_MAX_SECTORS, which is wrong and r/w of that size
may get error.

[mkp: tweaked to avoid setting rw_max twice and added typecast]

Cc: <stable@vger.kernel.org> # v4.4+
Fixes: ca369d51 ("block/sd: Fix device-imposed transfer length limits")
Signed-off-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

If sd_eh_action() decides to take the device offline there is
no point in returning FAILED, as taking the device offline
is the ultimate step in SCSI EH anyway.
So further escalation via SCSI EH is not likely to make a
difference and we can as well return SUCCESS.

Cc: Benjamin Block <bblock@linux.vnet.ibm.com>
Signed-off-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The current medium access timeout counter will be increased for
each command, so if there are enough failed commands we'll hit
the medium access timeout for even a single device failure and
the following kernel message is displayed:

sd H:C:T:L: [sdXY] Medium access timeout failure. Offlining disk!

Fix this by making the timeout per EH run, ie the counter will
only be increased once per device and EH run.

Fixes: 18a4d0a2 ("[SCSI] Handle disk devices which can not process medium access commands")
Cc: Ewan Milne <emilne@redhat.com>
Cc: Lawrence Obermann <loberman@redhat.com>
Cc: Benjamin Block <bblock@linux.vnet.ibm.com>
Cc: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This reverts commit 0dba1314. It causes
leaking of device numbers for SCSI when SCSI registers multiple gendisks
for one request_queue in succession. It can be easily reproduced using
Omar's script [1] on kernel with CONFIG_DEBUG_TEST_DRIVER_REMOVE.
Furthermore the protection provided by this commit is not needed anymore
as the problem it was fixing got also fixed by commit 165a5e22
"block: Move bdi_unregister() to del_gendisk()".

[1]: http://marc.info/?l=linux-block&m=148554717109098&w=2Signed-off-by: NJan Kara <jack@suse.cz>
Acked-by: NDan Williams <dan.j.williams@intel.com>
Tested-by: NOmar Sandoval <osandov@fb.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Commit <f2e767bb> ("mpt3sas: Force request partial completion
alignment") was not considering the case of commands not operating on
logical block size units (e.g. REQ_OP_ZONE_REPORT and its 64B aligned
partial replies). In this case, forcing alignment of resid to the device
logical block size can break the command result, e.g. in the case of
REQ_OP_ZONE_REPORT, the exact number of zone reported by the device.

Move the partial completion alignement check of mpt3sas to a generic
implementation in sd_done(). The check is added within the default
section of the initial req_op() switch case so that the report and reset
zone commands are ignored. In addition, as sd_done() is not called for
passthrough requests, resid corrections are not done as intended by the
initial mpt3sas patch.

Fixes: f2e767bb ("mpt3sas: Force request partial completion alignment")
Cc: <stable@vger.kernel.org> # v4.10
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Acked-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

And switch all callers to use scsi_execute instead.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Remove bogus evaluations of retval and sshdr when the device is offline,
and fix a possible NULL pointer dereference by allocating the 8 byte
sized sense header on stack.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

On an allocation failure of gd, the current exit path is via
out_free_devt which leaves sdpk still allocated and hence it gets
leaked. Fix this by correcting the order of resource free'ing with a
change in the error exit path labels.

Detected by CoverityScan, CID#1399519 ("Resource Leak")

Fixes: 0dba1314 ("scsi, block: fix duplicate bdi name registration crashes")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Reviewed-by: NBart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Fixes the following sparse warning:

drivers/scsi/sd.c:3087:6: warning:
 symbol 'sd_devt_release' was not declared. Should it be static?
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Warnings of the following form occur because scsi reuses a devt number
while the block layer still has it referenced as the name of the bdi
[1]:

 WARNING: CPU: 1 PID: 93 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x62/0x80
 sysfs: cannot create duplicate filename '/devices/virtual/bdi/8:192'
 [..]
 Call Trace:
  dump_stack+0x86/0xc3
  __warn+0xcb/0xf0
  warn_slowpath_fmt+0x5f/0x80
  ? kernfs_path_from_node+0x4f/0x60
  sysfs_warn_dup+0x62/0x80
  sysfs_create_dir_ns+0x77/0x90
  kobject_add_internal+0xb2/0x350
  kobject_add+0x75/0xd0
  device_add+0x15a/0x650
  device_create_groups_vargs+0xe0/0xf0
  device_create_vargs+0x1c/0x20
  bdi_register+0x90/0x240
  ? lockdep_init_map+0x57/0x200
  bdi_register_owner+0x36/0x60
  device_add_disk+0x1bb/0x4e0
  ? __pm_runtime_use_autosuspend+0x5c/0x70
  sd_probe_async+0x10d/0x1c0
  async_run_entry_fn+0x39/0x170

This is a brute-force fix to pass the devt release information from
sd_probe() to the locations where we register the bdi,
device_add_disk(), and unregister the bdi, blk_cleanup_queue().

Thanks to Omar for the quick reproducer script [2]. This patch survives
where an unmodified kernel fails in a few seconds.

[1]: https://marc.info/?l=linux-scsi&m=147116857810716&w=4
[2]: http://marc.info/?l=linux-block&m=148554717109098&w=2

Cc: James Bottomley <James.Bottomley@hansenpartnership.com>
Cc: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Jan Kara <jack@suse.cz>
Reported-by: NOmar Sandoval <osandov@osandov.com>
Tested-by: NOmar Sandoval <osandov@fb.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

->done can only be called for fs requests, so no need to check again here.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

And require all drivers that want to support BLOCK_PC to allocate it
as the first thing of their private data.  To support this the legacy
IDE and BSG code is switched to set cmd_size on their queues to let
the block layer allocate the additional space.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

This patch reverts commit f80de881 and avoids that sending a
WRITE SAME command to the iSCSI initiator triggers the following:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000014
TARGET_CORE[iSCSI]: Expected Transfer Length: 260096 does not match SCSI CDB Length: 512 for SAM Opcode: 0x41
IP: iscsi_tcp_segment_done+0x20b/0x310 [libiscsi_tcp]

Oops: 0000 [#1] SMP
Modules linked in: target_core_user uio target_core_iblock target_core_file iscsi_target_mod target_core_mod netconsole configfs crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel aes_x86_64 crypto_simd cryptd glue_helper virtio_console virtio_rng virtio_balloon serio_raw i2c_piix4 acpi_cpufreq button iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ext4 jbd2 mbcache virtio_blk virtio_net psmouse floppy drm_kms_helper syscopyarea
sysfillrect sysimgblt fb_sys_fops ttm drm virtio_pci
CPU: 2 PID: 5 Comm: kworker/u8:0 Not tainted 4.10.0-rc5-debug+ #3
Workqueue: iscsi_q_0 iscsi_xmitworker [libiscsi]
RIP: 0010:iscsi_tcp_segment_done+0x20b/0x310 [libiscsi_tcp]
Call Trace:
 iscsi_sw_tcp_xmit_segment+0x84/0x120 [iscsi_tcp]
 iscsi_sw_tcp_pdu_xmit+0x51/0x180 [iscsi_tcp]
 iscsi_tcp_task_xmit+0xb3/0x290 [libiscsi_tcp]
 iscsi_xmit_task+0x4e/0xc0 [libiscsi]
 iscsi_xmitworker+0x243/0x330 [libiscsi]
 process_one_work+0x1d8/0x4b0
 worker_thread+0x49/0x4a0
 kthread+0x102/0x140

Fixes: f80de881 ("sd: remove __data_len hack for WRITE SAME")
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: Jens Axboe <axboe@fb.com>
Cc: Lee Duncan <lduncan@suse.com>
Cc: Chris Leech <cleech@redhat.com>
Acked-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

In sd.c there are two comment references to 'struct scsi_device *sdp' as
an argument.  One of the references has a typo and the other should be a
reference to 'struct device *dev' instead.

Fixed by correcting the typo in the first and changing the explanation
in the second.
Signed-off-by: NJohn Pittman <jpittman@redhat.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

There is no good match of the zoned field of the block device
characteristics page for host-managed devices. For these devices, the
zoning model is derived directly from the device type. So ignore the
zoned field for these drives.

[mkp: typo]
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Zoned block devices force the use of READ/WRITE(16) commands by setting
sdkp->use_16_for_rw and clearing sdkp->use_10_for_rw. This result in
DPOFUA always being disabled for these drives as the assumed use of
the deprecated READ/WRITE(6) commands only looks at sdkp->use_10_for_rw.
Strenghten the test by also checking that sdkp->use_16_for_rw is false.
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>