dm: update relevant MODULE_AUTHOR entries to latest dm-devel mailing list

Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm: add helper macro for simple DM target module init and exit

Eliminate duplicate boilerplate code for simple modules that contain
a single DM target driver without any additional setup code.

Add a new module_dm() macro, which replaces the module_init() and
module_exit() with template functions that call dm_register_target()
and dm_unregister_target() respectively.

Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm: push error reporting down to dm_register_target()

Simplifies each DM target's init method by making dm_register_target()
responsible for its error reporting (on behalf of targets).

Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm: avoid spaces before function arguments or in favour of tabs

Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm: change "unsigned" to "unsigned int"

Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm: add missing SPDX-License-Indentifiers

'GPL-2.0-only' is used instead of 'GPL-2.0' because SPDX has
deprecated its use.

Suggested-by: John Wiele <jwiele@redhat.com>
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm bufio: Add flags argument to dm_bufio_client_create

Add a flags argument to dm_bufio_client_create and update all the
callers. This is in preparation to add the DM_BUFIO_NO_SLEEP flag.

Signed-off-by: Nathan Huckleberry <nhuck@google.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

dm/ebs: Change 'int rw' into 'enum req_op op'

Improve static type checking by using type 'enum req_op' instead of 'int'.
Make the role of the 'rw' arguments more clear by renaming these into
'op' (operation). This patch does not change any functionality since
REQ_OP_READ = READ = 0 and REQ_OP_WRITE = WRITE = 1.

Cc: Alasdair Kergon <agk@redhat.com>
Cc: Mike Snitzer <snitzer@kernel.org>
Cc: Heinz Mauelshagen <heinzm@redhat.com>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20220714180729.1065367-25-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

scsi: dm: Remove WRITE_SAME support

There are no more end-users of REQ_OP_WRITE_SAME left, so we can start
deleting it.

Link: https://lore.kernel.org/r/20220209082828.2629273-7-hch@lst.de
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

dm: use bdev_nr_sectors and bdev_nr_bytes instead of open coding them

Use the proper helpers to read the block device size.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Link: https://lore.kernel.org/r/20211018101130.1838532-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

dm: update target status functions to support IMA measurement

For device mapper targets to take advantage of IMA's measurement
capabilities, the status functions for the individual targets need to be
updated to handle the status_type_t case for value STATUSTYPE_IMA.

Update status functions for the following target types, to log their
respective attributes to be measured using IMA.
01. cache
02. crypt
03. integrity
04. linear
05. mirror
06. multipath
07. raid
08. snapshot
09. striped
10. verity

For rest of the targets, handle the STATUSTYPE_IMA case by setting the
measurement buffer to NULL.

For IMA to measure the data on a given system, the IMA policy on the
system needs to be updated to have the following line, and the system
needs to be restarted for the measurements to take effect.

/etc/ima/ima-policy
measure func=CRITICAL_DATA label=device-mapper template=ima-buf

The measurements will be reflected in the IMA logs, which are located at:

/sys/kernel/security/integrity/ima/ascii_runtime_measurements
/sys/kernel/security/integrity/ima/binary_runtime_measurements

These IMA logs can later be consumed by various attestation clients
running on the system, and send them to external services for attesting
the system.

The DM target data measured by IMA subsystem can alternatively
be queried from userspace by setting DM_IMA_MEASUREMENT_FLAG with
DM_TABLE_STATUS_CMD.

Signed-off-by: Tushar Sugandhi <tusharsu@linux.microsoft.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

dm-ebs: use bvec_virt

Use bvec_virt instead of open coding it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210804095634.460779-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

dm ebs: fix a few typos

s/retrievd/retrieved/
s/misalignement/misalignment/
s/funtion/function/

Signed-off-by: Bhaskar Chowdhury <unixbhaskar@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

dm ebs: avoid double unlikely() notation when using IS_ERR()

The definition of IS_ERR() already applies the unlikely() notation
when checking the error status of the passed pointer. For this
reason there is no need to have the same notation outside of
IS_ERR() itself.

Clean up code by removing redundant notation.

Signed-off-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

dm ebs: Fix incorrect checking for REQ_OP_FLUSH

REQ_OP_FLUSH was being treated as a flag, but the operation
part of bio->bi_opf must be treated as a whole. Change to
accessing the operation part via bio_op(bio) and checking
for equality.

Signed-off-by: John Dorminy <jdorminy@redhat.com>
Acked-by: Heinz Mauelshagen <heinzm@redhat.com>
Fixes: d3c7b35c20d60 ("dm: add emulated block size target")
Cc: stable@vger.kernel.org
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

dm ebs: use dm_bufio_forget_buffers

Use dm_bufio_forget_buffers instead of a block-by-block loop that
calls dm_bufio_forget. dm_bufio_forget_buffers is faster than the loop
because it searches for used buffers using rb-tree.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

dm ebs: pass discards down to underlying device

Make use of dm_bufio_issue_discard() to pass discards down to the
underlying device.

Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

dm: add emulated block size target

This new target is similar to the linear target except that it emulates
a smaller logical block size on a device with a larger logical block
size. Its main purpose is to emulate 512 byte sectors on 4K native
disks (i.e. 512e).

See Documentation/admin-guide/device-mapper/dm-ebs.rst for details.

Reviewed-by: Damien Le Moal <DamienLeMoal@wdc.com>
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org> [Kconfig fixes]
Signed-off-by: Zheng Bin <zhengbin13@huawei.com> [static fixes]
Signed-off-by: Mike Snitzer <snitzer@redhat.com>