scsi: replace the fmode_t argument to ->sg_io_fn with a simple bool

Instead of passing a fmode_t and only checking it for FMODE_WRITE, pass
a bool open_for_write to prepare for callers that won't have the fmode_t.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20230608110258.189493-21-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

scsi: replace the fmode_t argument to scsi_cmd_allowed with a simple bool

Instead of passing a fmode_t and only checking it for FMODE_WRITE, pass
a bool open_for_write to prepare for callers that won't have the fmode_t.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20230608110258.189493-19-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

scsi: bsg: Drop needless assignment in scsi_bsg_sg_io_fn()

Commit ce70fd9a551a ("scsi: core: Remove the cmd field from struct
scsi_request") refactored scsi_bsg_sg_io_fn() so that it does not allocate
directly and hence does not return -ENOMEM in its error case. That makes a
remaining assignment of -ENOMEM to the return variable needless.

Drop this needless assignment in scsi_bsg_sg_io_fn().

No functional change. No change in resulting object code.

Link: https://lore.kernel.org/r/20220315055325.14974-1-lukas.bulwahn@gmail.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: core: Move the result field from struct scsi_request to struct scsi_cmnd

Prepare for removing the scsi_request structure by moving the result field
to struct scsi_cmnd.

Link: https://lore.kernel.org/r/20220224175552.988286-7-hch@lst.de
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: core: Move the resid_len field from struct scsi_request to struct scsi_cmnd

Prepare for removing the scsi_request structure by moving the resid_len
field to struct scsi_cmnd.

Link: https://lore.kernel.org/r/20220224175552.988286-6-hch@lst.de
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: core: Remove the sense and sense_len fields from struct scsi_request

Just use the sense_buffer field in struct scsi_cmnd for the sense data and
move the sense_len field over to struct scsi_cmnd.

Link: https://lore.kernel.org/r/20220224175552.988286-5-hch@lst.de
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: core: Remove the cmd field from struct scsi_request

Now that each scsi_request is backed by a scsi_cmnd, there is no need to
indirect the CDB storage. Change all submitters of SCSI passthrough
requests to store the CDB information directly in the scsi_cmnd, and while
doing so allocate the full 32 bytes that cover all Linux supported SCSI
hosts instead of requiring dynamic allocation for > 16 byte CDBs. On
64-bit systems this does not change the size of the scsi_cmnd at all, while
on 32-bit systems it slightly increases it for now, but that increase will
be made up by the removal of the remaining scsi_request fields.

Link: https://lore.kernel.org/r/20220224175552.988286-4-hch@lst.de
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

block: remove the gendisk argument to blk_execute_rq

Remove the gendisk aregument to blk_execute_rq and blk_execute_rq_nowait
given that it is unused now. Also convert the boolean at_head parameter
to actually use the bool type while touching the prototype.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20211126121802.2090656-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove blk_{get,put}_request

These are now pointless wrappers around blk_mq_{alloc,free}_request,
so remove them.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20211025070517.1548584-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

scsi: add a scsi_alloc_request helper

Add a new helper that calls blk_get_request and initializes the
scsi_request to avoid the indirect call through ->.initialize_rq_fn.

Note that this makes the pktcdvd driver depend on the SCSI core, but
given that only SCSI devices support SCSI passthrough requests that
is not a functional change.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20211021060607.264371-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

scsi: bsg: Fix commands without data transfer in scsi_bsg_sg_io_fn()

Set ret to 0 after the initial permission checks to avoid leaking -EPERM
for commands without data transfer.

Link: https://lore.kernel.org/r/20210731074027.1185545-2-hch@lst.de
Fixes: 75ca56409e5b ("scsi: bsg: Move the whole request execution into the SCSI/transport handlers")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: bsg: Move the whole request execution into the SCSI/transport handlers

Remove the amount of indirect calls by making the handler responsible for
the entire execution of the request.

Link: https://lore.kernel.org/r/20210729064845.1044147-5-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: bsg: Simplify device registration

Use the per-device cdev_device_interface to store the bsg data in the char
device inode, and thus remove the need to embedd the bsg_class_device
structure in the request_queue.

Link: https://lore.kernel.org/r/20210729064845.1044147-2-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: scsi_ioctl: Simplify SCSI passthrough permission checking

Remove the separate command filter structure and just use a switch
statement (which also cought two duplicate commands), return a bool and
give the function a sensible name.

Link: https://lore.kernel.org/r/20210724072033.1284840-18-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: bsg: Move bsg_scsi_ops to drivers/scsi/

Move the SCSI-specific bsg code in the SCSI midlayer instead of in the
common bsg code. This just keeps the common bsg code block/ and also
allows building it as a module.

Link: https://lore.kernel.org/r/20210724072033.1284840-15-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>