This avoids the extra call to revalidate_disk_size in sd_rescan and
is otherwise a no-op because the size did not change, or we are in
the probe path.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Acked-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Switch from using blk_register_region to the probe callback passed to
__register_blkdev to disable the request_module call for an unclaimed
dev_t in the SD majors.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Acked-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Rename scsi_init_io() to scsi_alloc_sgtables(), and ensure callers call
scsi_free_sgtables() to cleanup failures close to scsi_init_io() instead of
leaking it down the generic I/O submission path.

Link: https://lore.kernel.org/r/20201005084130.143273-9-hch@lst.deReviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Some iSCSI targets went with the traditional "export N ports" approach and
then allowed the initiator to multipath over them. Other targets went the
opposite direction and export a single port, and then software on the
target side performs load balancing and failover to other targets via an
iSCSI specific feature or IP takover.

The problem for the 2nd type of config is we quickly run out of our five
retries and get I/O errors. In these setups we want to reduce resource use
on the initiator side so we only wanted the one session and no
dm-multipath.  To handle traditional multipath operations like failover we
do IP takover on the target side. So we would have an iSCSI target running
on node1. Some monitoring software decides it's dead or the node is
overloaded so it starts the iSCSI target on node2. The problem is for the
failover case where we might have the equivalent of a dm-multipath
temporary all paths down, or we just have to try more than 5 nodes before
finding a good one.

To handle this type of issue allow the user to configure the disk cmd
retries from -1 to the current max of 5. -1 means infinite retries and
should be used for setups where some other setting is going to control when
to fail. For example iSCSI has the replacement/recovery timeout and fc
(some users have used FC with NPIV and done something similar as IP
takover) has dev_loss_tmo/fast_io_fail which will eventually expire and
fail I/O.

Link: https://lore.kernel.org/r/1601566554-26752-3-git-send-email-michael.christie@oracle.comReviewed-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMike Christie <michael.christie@oracle.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Make sure to call sd_zbc_init_disk() when the sdkp->zoned field is known,
that is, once sd_read_block_characteristics() is executed in
sd_revalidate_disk(), so that host-aware disks also get initialized.  To do
so, move sd_zbc_init_disk() call in sd_zbc_revalidate_zones() and make sure
to execute it for all zoned disks, including for host-aware disks used as
regular disks as these disk zoned model may be changed back to BLK_ZONED_HA
when partitions are deleted.

Link: https://lore.kernel.org/r/20200915073347.832424-3-damien.lemoal@wdc.com
Fixes: 5795eb44 ("scsi: sd_zbc: emulate ZONE_APPEND commands")
Cc: <stable@vger.kernel.org> # v5.8+
Reported-by: NBorislav Petkov <bp@alien8.de>
Tested-by: NBorislav Petkov <bp@suse.de>
Reviewed-by: NJohannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When CONFIG_BLK_DEV_ZONED is disabled, allow using host-aware ZBC disks as
regular disks. In this case, ensure that command completion is correctly
executed by changing sd_zbc_complete() to return good_bytes instead of 0
and causing a hang during device probe (endless retries).

When CONFIG_BLK_DEV_ZONED is enabled and a host-aware disk is detected to
have partitions, it will be used as a regular disk. In this case, make sure
to not do anything in sd_zbc_revalidate_zones() as that triggers warnings.

Since all these different cases result in subtle settings of the disk queue
zoned model, introduce the block layer helper function
blk_queue_set_zoned() to generically implement setting up the effective
zoned model according to the disk type, the presence of partitions on the
disk and CONFIG_BLK_DEV_ZONED configuration.

Link: https://lore.kernel.org/r/20200915073347.832424-2-damien.lemoal@wdc.com
Fixes: b7205307 ("block: allow partitions on host aware zone devices")
Cc: <stable@vger.kernel.org>
Reported-by: NBorislav Petkov <bp@alien8.de>
Suggested-by: NChristoph Hellwig <hch@infradead.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJohannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Switch to use bdev_check_media_change instead of check_disk_change and
call sd_revalidate_disk manually.  As sd also calls sd_revalidate_disk
manually during probe and open, the extra call into ->revalidate_disk
from bdev_disk_changed is not required either, so stop wiring up the
method.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJohannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Instead of calling revalidate_disk just do the work directly by
calling sd_revalidate_disk, and revalidate_disk_size where needed.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJosef Bacik <josef@toxicpanda.com>
Reviewed-by: NJohannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Currently, for zoned disks, since blk_revalidate_disk_zones() requires the
disk capacity to be set already to operate correctly, zones revalidation
can only be done on the second revalidate scan once the gendisk capacity is
set at the end of the first scan. As a result, if zone revalidation fails,
there is no second chance to recover from the failure and the disk capacity
is changed to 0, with the disk left unusable.

This can be improved by shuffling around code, specifically, by moving the
call to sd_zbc_revalidate_zones() from sd_zbc_read_zones() to the end of
sd_revalidate_disk(), after set_capacity_revalidate_and_notify() is called
to set the gendisk capacity. With this change, if sd_zbc_revalidate_zones()
fails on the first scan, the second scan will call it again to recover, if
possible.

Using the new struct scsi_disk fields rev_nr_zones and rev_zone_blocks,
sd_zbc_revalidate_zones() does actual work only if it detects a change with
the disk zone configuration. This means that for a successful zones
revalidation on the first scan, the second scan will not cause another
heavy full check.

While at it, remove the unecesary "extern" declaration of
sd_zbc_read_zones().

Link: https://lore.kernel.org/r/20200731054928.668547-1-damien.lemoal@wdc.comReviewed-by: NJohannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Fix the kdoc comment of the function sd_ioctl_common() to avoid a compiler
warning when compiling with W=1.

No functional changes.

Link: https://lore.kernel.org/r/20200706123354.452047-1-damien.lemoal@wdc.comSigned-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Export through sysfs as a scsi_disk attribute the zoned capabilities of a
disk ("zoned_cap" attribute file). This new attribute indicates in human
readable form (i.e. a string) the zoned block capabilities implemented by
the disk as found in the ZONED field of the disk block device
characteristics VPD page. The possible values are:

 - "none": ZONED=00b (not reported), regular disk

 - "host-aware": ZONED=01b, host-aware ZBC disk

 - "drive-managed": ZONED=10b, drive-managed ZBC disk (regular disk
   interface)

For completeness, also add the following value which is detected using the
device type rather than the ZONED field:

 - "host-managed": device type = 0x14 (TYPE_ZBC), host-managed ZBC disk

This new sysfs attribute is purely informational and complementary to the
"zoned" device request queue sysfs attribute as it allows applications and
user daemons (e.g.  udev) to easily differentiate regular disks from
drive-managed SMR disks without the need for direct access tools such as
provided by sg3utils.

Link: https://lore.kernel.org/r/20200515054856.1408575-1-damien.lemoal@wdc.comReviewed-by: NJohannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Print a message indicating that a disk is a drive-managed SMR model when
such drive is found using the ZONED field of the Block Device
Characteristics VPD page (IDENTIFY data on ATA side).

[mkp: typo]

Link: https://lore.kernel.org/r/20200514081953.1252087-1-damien.lemoal@wdc.comReviewed-by: NJohannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Emulate ZONE_APPEND for SCSI disks using a regular WRITE(16) command
with a start LBA set to the target zone write pointer position.

In order to always know the write pointer position of a sequential write
zone, the write pointer of all zones is tracked using an array of 32bits
zone write pointer offset attached to the scsi disk structure. Each
entry of the array indicate a zone write pointer position relative to
the zone start sector. The write pointer offsets are maintained in sync
with the device as follows:
1) the write pointer offset of a zone is reset to 0 when a
   REQ_OP_ZONE_RESET command completes.
2) the write pointer offset of a zone is set to the zone size when a
   REQ_OP_ZONE_FINISH command completes.
3) the write pointer offset of a zone is incremented by the number of
   512B sectors written when a write, write same or a zone append
   command completes.
4) the write pointer offset of all zones is reset to 0 when a
   REQ_OP_ZONE_RESET_ALL command completes.

Since the block layer does not write lock zones for zone append
commands, to ensure a sequential ordering of the regular write commands
used for the emulation, the target zone of a zone append command is
locked when the function sd_zbc_prepare_zone_append() is called from
sd_setup_read_write_cmnd(). If the zone write lock cannot be obtained
(e.g. a zone append is in-flight or a regular write has already locked
the zone), the zone append command dispatching is delayed by returning
BLK_STS_ZONE_RESOURCE.

To avoid the need for write locking all zones for REQ_OP_ZONE_RESET_ALL
requests, use a spinlock to protect accesses and modifications of the
zone write pointer offsets. This spinlock is initialized from sd_probe()
using the new function sd_zbc_init().
Co-developed-by: NDamien Le Moal <Damien.LeMoal@wdc.com>
Signed-off-by: NJohannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Some USB bridge devices will return a default set of characteristics during
initialization. And then, once an attached drive has spun up, substitute
the actual parameters reported by the drive. According to the SCSI spec,
the device should return a UNIT ATTENTION in case any reported parameters
change. But in this case the change is made silently after a small window
where default values are reported.

Commit a83da8a4 ("scsi: sd: Optimal I/O size should be a multiple of
physical block size") validated the reported optimal I/O size against the
physical block size to overcome problems with devices reporting nonsensical
transfer sizes. However, this validation did not account for the fact that
aforementioned devices will return default values during a brief window
during spin-up. The subsequent change in reported characteristics would
invalidate the checking that had previously been performed.

Unset a previously configured optimal I/O size should the sanity checking
fail on subsequent revalidate attempts.

Link: https://lore.kernel.org/r/33fb522e-4f61-1b76-914f-c9e6a3553c9b@gmail.com
Cc: Bryan Gurney <bgurney@redhat.com>
Cc: <stable@vger.kernel.org>
Reported-by: NBernhard Sulzer <micraft.b@gmail.com>
Tested-by: NBernhard Sulzer <micraft.b@gmail.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

block/genhd provides set_capacity_revalidate_and_notify() for sending RESIZE
notifications via uevents. This notification is newly added to scsi sd.
Signed-off-by: NBalbir Singh <sblbir@amazon.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Host-aware SMR drives can be used with the commands to explicitly manage
zone state, but they can also be used as normal disks.  In the former
case it makes perfect sense to allow partitions on them, in the latter
it does not, just like for host managed devices.  Add a check to
add_partition to allow partitions on host aware devices, but give
up any zone management capabilities in that case, which also catches
the previously missed case of adding a partition vs just scanning it.

Because sd can rescan the attribute at runtime it needs to check if
a disk has partitions, for which a new helper is added to genhd.h.

Fixes: 5eac3eb3 ("block: Remove partition support for zoned block devices")
Reported-by: NBorislav Petkov <bp@suse.de>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Tested-by: NDamien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: NDamien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

If an attached disk with protection information enabled is reformatted
to Type 0 the revalidation code does not clear the original protection
type and subsequent accesses will keep setting RDPROTECT/WRPROTECT.

Set the protection type to 0 if the disk reports PROT_EN=0 in READ
CAPACITY(16).

[mkp: commit desc]

Fixes: fe542396 ("[SCSI] sd: Ensure we correctly disable devices with unknown protection type")
Link: https://lore.kernel.org/r/1578532344-101668-1-git-send-email-chenxiang66@hisilicon.comSigned-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Each driver calling scsi_ioctl() gets an equivalent compat_ioctl()
handler that implements the same commands by calling scsi_compat_ioctl().

The scsi_cmd_ioctl() and scsi_cmd_blk_ioctl() functions are compatible
at this point, so any driver that calls those can do so for both native
and compat mode, with the argument passed through compat_ptr().

With this, we can remove the entries from fs/compat_ioctl.c.  The new
code is larger, but should be easier to maintain and keep updated with
newly added commands.
Reviewed-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Acked-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>

In the case of a report zones command failure, instead of simply printing
the host_byte and driver_byte values returned, print a message that is more
human readable and useful, adding sense codes too.

To do so, use the already defined sd_print_sense_hdr() and
sd_print_result() functions by moving the declaration of these functions
into sd.h.

Link: https://lore.kernel.org/r/20191125070518.951717-1-damien.lemoal@wdc.comSigned-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Implement REQ_OP_ZONE_OPEN, REQ_OP_ZONE_CLOSE and REQ_OP_ZONE_FINISH
support to allow explicit control of zone states.

Contains contributions from Matias Bjorling, Hans Holmberg,
Keith Busch and Damien Le Moal.
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAjay Joshi <ajay.joshi@wdc.com>
Signed-off-by: NMatias Bjorling <matias.bjorling@wdc.com>
Signed-off-by: NHans Holmberg <hans.holmberg@wdc.com>
Signed-off-by: NKeith Busch <kbusch@kernel.org>
Signed-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Variable dif in function sd_setup_read_write_cmnd() is the return value of
function scsi_host_dif_capable() which returns dif capability of disks.  If
define it as bool, even for the disks which support DIF3, the function
still return dif=1, which causes IO error. So define variable dif as
unsigned int instead of bool.

Fixes: e249e42d ("scsi: sd: Clean up sd_setup_read_write_cmnd()")
Link: https://lore.kernel.org/r/1571725628-132736-1-git-send-email-chenxiang66@hisilicon.comSigned-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The sed_ioctl() function is written to be compatible between
32-bit and 64-bit processes, however compat mode is only
wired up for nvme, not for sd.

Add the missing call to sed_ioctl() in sd_compat_ioctl().

Fixes: d80210f2 ("sd: add support for TCG OPAL self encrypting disks")
Cc: linux-scsi@vger.kernel.org
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>

I've got a report about a UAS drive enclosure reporting back Sense: Logical
unit access not authorized if the drive it holds is password protected.
While the drive is obviously unusable in that state as a mass storage
device, it still exists as a sd device and when the system is asked to
perform a suspend of the drive, it will be sent a SYNCHRONIZE CACHE. If
that fails due to password protection, the error must be ignored.

Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20190903101840.16483-1-oneukum@suse.comSigned-off-by: NOliver Neukum <oneukum@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Rework from previous work by:
Sujit Reddy Thumma <sthumma@codeaurora.org>

Until now the scsi mid-layer forbids runtime suspend till userspace enables
it. This is mainly to quarantine some disks with broken runtime power
management or have high latencies executing suspend resume callbacks. If
the userspace doesn't enable the runtime suspend the underlying hardware
will be always on even when it is not doing any useful work and thus
wasting power.

Some low-level drivers for the controllers can efficiently use runtime
power management to reduce power consumption and improve battery life.
Allow runtime suspend parameters override within the LLD itself instead of
waiting for userspace to control the power management.

Link: https://lore.kernel.org/r/1568649411-5127-2-git-send-email-stanley.chu@mediatek.comReviewed-by: NAvri Altman <avri.altman@wdc.com>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NStanley Chu <stanley.chu@mediatek.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Currently t10_pi_prepare/t10_pi_complete functions are called during the
NVMe and SCSi layers command preparetion/completion, but their actual
place should be the block layer since T10-PI is a general data integrity
feature that is used by block storage protocols. Introduce .prepare_fn
and .complete_fn callbacks within the integrity profile that each type
can implement according to its needs.
Suggested-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Suggested-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NMax Gurtovoy <maxg@mellanox.com>

Fixed to not call queue integrity functions if BLK_DEV_INTEGRITY
isn't defined in the config.
Signed-off-by: NJens Axboe <axboe@kernel.dk>

For commands completing with a resid not aligned on the device logical
sector size, also print the command CDB in addition to the current message
to help debug hardware generating such incorrect command completion
information.

Link: https://lore.kernel.org/r/20190828053511.14818-1-damien.lemoal@wdc.comSigned-off-by: NDamien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch implements the zone reset all operation for sd_zbc.c. We add
a new boolean parameter for the sd_zbc_setup_reset_cmd() to indicate
REQ_OP_ZONE_RESET_ALL command setup. Along with that we add support in
the completion path for the zone reset all.
Reviewed-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NDamien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Make sd_probe() easier to read by inlining sd_probe_part2(). This patch
does not change any functionality.

[mkp: applied by hand]

Cc: Lee Duncan <lduncan@suse.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

As explained during the 2018 LSF/MM session about increasing SCSI disk
probing concurrency, the problems with the current probing approach are as
follows:

 - The driver core is unaware of asynchronous SCSI LUN probing.
   wait_for_device_probe() waits for all asynchronous probes except
   asynchronous SCSI disk probes.

 - There is unnecessary serialization between sd_probe() and sd_remove().
   This can lead to a deadlock.

Hence this patch that modifies the sd driver such that it uses the driver
core framework for asynchronous probing. The async domain and
get_device()/put_device() pairs that became superfluous due to this change
are removed.

This patch does not affect the time needed for loading the scsi_debug
kernel module with parameters delay=0 and max_luns=256.

This patch depends on commit ef0ff683 ("driver core: Probe devices
asynchronously instead of the driver") that went upstream in kernel version
v5.1-rc1.

Cc: Lee Duncan <lduncan@suse.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

sd.c is the only sd file missing licensing information.  Add a
GPLv2 tag for the default kernel license.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have MODULE_LICENCE("GPL*") inside which was used in the initial
   scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit 20bd1d02.

This patch introduced regressions for devices that come online in
read-only state and subsequently switch to read-write.

Given how the partition code is currently implemented it is not
possible to persist the read-only flag across a device revalidate
call. This may need to get addressed in the future since it is common
for user applications to proactively call BLKRRPART.

Reverting this commit will re-introduce a regression where a
device-initiated revalidate event will cause the admin state to be
forgotten. A separate patch will address this issue.

Fixes: 20bd1d02 ("scsi: sd: Keep disk read-only when re-reading partition")
Cc: <stable@vger.kernel.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Hibernation hangs as follows due to commit 21e6ba3f when using SATA:

Call Trace:
 __schedule+0x464/0xe70
 schedule+0x4e/0xd0
 blk_queue_enter+0x5fe/0x7e0
 generic_make_request+0x313/0x950
 submit_bio+0x9b/0x250
 submit_bio_wait+0xc9/0x110
 hib_submit_io+0x17d/0x1c0
 write_page+0x61/0xa0
 swap_write_page+0x4b/0x1f0
 swsusp_write+0x2f9/0x3d0
 hibernate.cold.10+0x108/0x231
 state_store+0xf7/0x100
 kobj_attr_store+0x37/0x50
 sysfs_kf_write+0x87/0xa0
 kernfs_fop_write+0x186/0x240
 __vfs_write+0x4d/0x90
 vfs_write+0xfa/0x260
 ksys_write+0xb9/0x1a0
 __x64_sys_write+0x43/0x50
 do_syscall_64+0x71/0x210
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Hence revert commit 21e6ba3f.

Cc: Pavel Machek <pavel@ucw.cz>
Reported-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Reverts commit d16ece57 to make a clean revert of its predecessor
possible.

Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Acked-by: NPavel Machek <pavel@ucw.cz>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Currently, an empty disk->events field tells the block layer not to
forward media change events to user space. This was done in commit
7c88a168 ("block: don't propagate unlisted DISK_EVENTs to userland")
in order to avoid events from "fringe" drivers to be forwarded to user
space. By doing so, the block layer lost the information which events
were supported by a particular block device, and most importantly,
whether or not a given device supports media change events at all.

Prepare for not interpreting the "events" field this way in the future
any more. This is done by adding an additional field "event_flags" to
struct gendisk, and two flag bits that can be set to have the device
treated like one that had the "events" field set to a non-zero value
before. This applies only to the sd and sr drivers, which are changed to
set the new flags.

The new flags are DISK_EVENT_FLAG_POLL to enforce polling of the device
for synchronous events, and DISK_EVENT_FLAG_UEVENT to tell the
blocklayer to generate udev events from kernel events.

In order to add the event_flags field to struct gendisk, the events
field is converted to an "unsigned short"; it doesn't need to hold
values bigger than 2 anyway.

This patch doesn't change behavior.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin Wilck <mwilck@suse.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Currently support for 64-bit sector_t and blkcnt_t is optional on 32-bit
architectures.  These types are required to support block device and/or
file sizes larger than 2 TiB, and have generally defaulted to on for
a long time.  Enabling the option only increases the i386 tinyconfig
size by 145 bytes, and many data structures already always use
64-bit values for their in-core and on-disk data structures anyway,
so there should not be a large change in dynamic memory usage either.

Dropping this option removes a somewhat weird non-default config that
has cause various bugs or compiler warnings when actually used.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Commit a83da8a4 ("scsi: sd: Optimal I/O size should be a multiple
of physical block size") split one conditional into several separate
statements in an effort to provide more accurate warning messages when
a device reports a nonsensical value. However, this reorganization
accidentally dropped the precondition of the reported value being
larger than zero. This lead to a warning getting emitted on devices
that do not report an optimal I/O size at all.

Remain silent if a device does not report an optimal I/O size.

Fixes: a83da8a4 ("scsi: sd: Optimal I/O size should be a multiple of physical block size")
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: <stable@vger.kernel.org>
Reported-by: NHussam Al-Tayeb <ht990332@gmx.com>
Tested-by: NHussam Al-Tayeb <ht990332@gmx.com>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The scsi_end_request() function calls scsi_cmd_to_driver() indirectly and
hence needs the disk->private_data pointer. Avoid that that pointer is
cleared before all affected I/O requests have finished. This patch avoids
that the following crash occurs:

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
Call trace:
 scsi_mq_uninit_cmd+0x1c/0x30
 scsi_end_request+0x7c/0x1b8
 scsi_io_completion+0x464/0x668
 scsi_finish_command+0xbc/0x160
 scsi_eh_flush_done_q+0x10c/0x170
 sas_scsi_recover_host+0x84c/0xa98 [libsas]
 scsi_error_handler+0x140/0x5b0
 kthread+0x100/0x12c
 ret_from_fork+0x10/0x18

Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Jason Yan <yanaijie@huawei.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Reported-by: NJason Yan <yanaijie@huawei.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Make sd_probe() easier to read by inlining sd_probe_part2(). This patch
does not change any functionality.

Cc: Lee Duncan <lduncan@suse.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

As explained during the 2018 LSF/MM session about increasing SCSI disk
probing concurrency, the problems with the current probing approach are as
follows:

- The driver core is unaware of asynchronous SCSI LUN probing.
  wait_for_device_probe() waits for all asynchronous probes except
  asynchronous SCSI disk probes.

- There is unnecessary serialization between sd_probe() and sd_remove().
  This can lead to a deadlock.

Hence this patch that modifies the sd driver such that it uses the driver
core framework for asynchronous probing. The async domains and
get_device()/put_device() pairs that became superfluous due to this change
are removed.

This patch does not affect the time needed for loading the scsi_debug
kernel module with parameters delay=0 and max_luns=256.

This patch depends on commit ef0ff683 ("driver core: Probe devices
asynchronously instead of the driver") that went upstream in kernel version
v5.1-rc1.

Cc: Lee Duncan <lduncan@suse.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>