Make use of a new interface provided by iov_iter, backed by
scatter-gather list of iovec, instead of the old interface based on
sg_iovec. Also use iov_iter_advance() instead of manual iteration.

This commit should contain only literal replacements, without
functional changes.

Cc: Christoph Hellwig <hch@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Doug Gilbert <dgilbert@interlog.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
Signed-off-by: Kent Overstreet <kmo@daterainc.com>
[dpark: add more description in commit message]
Signed-off-by: Dongsu Park <dongsu.park@profitbricks.com>
[hch: fixed to do a deep clone of the iov_iter, and to properly use
      the iov_iter direction]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

SPC-3 defines SERVICE ACTION IN(12) and SERVICE ACTION IN(16).
So rename SERVICE_ACTION_IN to SERVICE_ACTION_IN_16 to be
consistent with SPC and to allow for better distinction.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Tested-by: Robert Elliott <elliott@hp.com>
Reviewed-by: Robert Elliott <elliott@hp.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Fix an error path in SCSI_IOCTL_SEND_COMMAND that calls
blk_put_request(rq) on an invalid IS_ERR(rq) pointer.

Fixes: a492f075450f ("block,scsi: fixup blk_get_request dead queue scenarios")
Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

When sg_scsi_ioctl() fails to prepare request to submit in
blk_rq_map_kern() we jump to a label where we just end up copying
(luckily zeroed-out) kernel buffer to userspace instead of reporting
error. Fix the problem by jumping to the right label.

CC: Jens Axboe <axboe@kernel.dk>
CC: linux-scsi@vger.kernel.org
CC: stable@vger.kernel.org
Coverity-id: 1226871
Signed-off-by: Jan Kara <jack@suse.cz>

Fixed up the, now unused, out label.

Signed-off-by: Jens Axboe <axboe@fb.com>

A bit of churn on the for-linus side that would be nice to have
in the core bits for 3.18, so pull it in to catch us up and make
forward progress easier.

Signed-off-by: Jens Axboe <axboe@fb.com>

Conflicts:
	block/scsi_ioctl.c

The blk_get_request function may fail in low-memory conditions or during
device removal (even if __GFP_WAIT is set). To distinguish between these
errors, modify the blk_get_request call stack to return the appropriate
ERR_PTR. Verify that all callers check the return status and consider
IS_ERR instead of a simple NULL pointer check.

For consistency, make a similar change to the blk_mq_alloc_request leg
of blk_get_request.  It may fail if the queue is dead, or the caller was
unwilling to wait.

Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com>
Acked-by: Jiri Kosina <jkosina@suse.cz> [for pktdvd]
Acked-by: Boaz Harrosh <bharrosh@panasas.com> [for osd]
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

The blk-core dead queue checks introduce an error scenario to
blk_get_request that returns NULL if the request queue has been
shutdown. This affects the behavior for __GFP_WAIT callers, who should
verify the return value before dereferencing.

Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com>
Acked-by: Jiri Kosina <jkosina@suse.cz> [for pktdvd]
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

Before commit 2cada584b200 ("block: cleanup error handling in sg_io"),
we had ret = 0 before entering the last big if block of sg_io.

Since 2cada584b200, ret = -EFAULT, which breaks hdparm:

/dev/sda:
 setting Advanced Power Management level to 0xc8 (200)
 HDIO_DRIVE_CMD failed: Bad address
 APM_level      = 128

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Fixes: 2cada584b200 ("block: cleanup error handling in sg_io")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>

blk_rq_set_block_pc() memsets rq->cmd to 0, so it should come
immediately after blk_get_request() to avoid overwriting the
user-supplied CDB.  Also check for failure to allocate rq.

Fixes: f27b087b81b7 ("block: add blk_rq_set_block_pc()")
Cc: <stable@vger.kernel.org> # 3.16.x
Signed-off-by: Tony Battersby <tonyb@cybernetics.com>
Signed-off-by: Jens Axboe <axboe@fb.com>