Since commit 0653c358 ("scsi: Drop gdth driver"), functions
scsi_{get,free}_host_dev() no longer have any in-tree users, so delete
them.

Link: https://lore.kernel.org/r/1631528047-30150-1-git-send-email-john.garry@huawei.comReviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Nacked-by: NHannes Reinecke <hare@suse.de>

There are no dependencies in <scsi/scsi_cmnd.h> on the <scsi/scsi_host.h>
header file. Hence remove the scsi_host.h include directive from
scsi_cmnd.h. This include directive was introduced in February 2021 by
commit af183095 ("scsi: core: Add mq_poll support to SCSI layer").

Link: https://lore.kernel.org/r/20210917212751.2676054-1-bvanassche@acm.org
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Reviewed-by: NHimanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

It is never read, so get rid of it.

Link: https://lore.kernel.org/r/1628862553-179450-4-git-send-email-john.garry@huawei.comReviewed-by: NHannes Reinecke <hare@suse.de>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Link: https://lore.kernel.org/r/20210806040023.5355-2-martin.petersen@oracle.com
Cc: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Since all scsi_cmnd.request users are gone, remove the request pointer
from struct scsi_cmnd.

Link: https://lore.kernel.org/r/20210809230355.8186-53-bvanassche@acm.org
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Prepare for removal of the request pointer by using scsi_cmd_to_rq()
instead. Cast away constness where necessary when passing a SCSI command
pointer to scsi_cmd_to_rq(). This patch does not change any functionality.

Link: https://lore.kernel.org/r/20210809230355.8186-3-bvanassche@acm.org
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Ming Lei <ming.lei@redhat.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The 'request' member of struct scsi_cmnd is superfluous. The struct request
and struct scsi_cmnd data structures are adjacent and hence the request
pointer can be derived easily from a scsi_cmnd pointer. Introduce a helper
function that performs that conversion in a type-safe way. This patch is
the first step towards removing the request member from struct
scsi_cmnd. Making that change has the following advantages:

 - This is a performance optimization since adding an offset to a pointer
   takes less time than dereferencing a pointer.

 - struct scsi_cmnd becomes smaller.

Link: https://lore.kernel.org/r/20210809230355.8186-2-bvanassche@acm.org
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Ming Lei <ming.lei@redhat.com>
Reviewed-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Move the sg_timeout and sg_reserved_size fields into the bsg_device and
scsi_device structures as they have nothing to do with generic block I/O.
Note that these values are now separate for bsg vs. SCSI device node
access, but that just matches how /dev/sg vs the other nodes has always
behaved.

Link: https://lore.kernel.org/r/20210729064845.1044147-4-hch@lst.deSigned-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

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.deSigned-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Just call scsi_ioctl() in sg as that has the same effect.

Link: https://lore.kernel.org/r/20210724072033.1284840-25-hch@lst.deSigned-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Merge the ioctl handling in block/scsi_ioctl.c into its only caller in
drivers/scsi/scsi_ioctl.c.

Link: https://lore.kernel.org/r/20210724072033.1284840-19-hch@lst.deSigned-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Merge scsi_req_init() into its only caller.

Link: https://lore.kernel.org/r/20210724072033.1284840-16-hch@lst.deSigned-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Ensure SCSI ULD only has to call a single ioctl helper.  This also adds a
bunch of missing ioctls to the ch driver, and removes the need for a
duplicate implementation of SCSI_IOCTL_SEND_COMMAND command.

Link: https://lore.kernel.org/r/20210724072033.1284840-12-hch@lst.deSigned-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Just handle the compat case in scsi_ioctl() using in_compat_syscall().

Link: https://lore.kernel.org/r/20210724072033.1284840-7-hch@lst.deSigned-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Add a new flag for devices that erroneously establish MEDIUM MAY HAVE
CHANGED unit attentions. Drivers can set this flag to make the SCSI
layer ignore media change events during resume.

[mkp: add "ignore" and add corresponding flag to struct scsi_device]

Link: https://lore.kernel.org/r/20210704075403.147114-2-martin.kepplinger@puri.smReviewed-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin Kepplinger <martin.kepplinger@puri.sm>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

scsi_get_lba() confusingly returned the block layer sector number expressed
in units of 512 bytes. Now that we have a more aptly named
scsi_get_sector() function, make scsi_get_lba() return the actual LBA.

Link: https://lore.kernel.org/r/20210609033929.3815-13-martin.petersen@oracle.comReviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NBenjamin Block <bblock@linux.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Message-Id: <20210609033929.3815-13-martin.petersen@oracle.com>

Since scsi_get_lba() returns a sector_t value instead of the LBA, the name
of that function is confusing. Introduce an identical function
scsi_get_sector().

Link: https://lore.kernel.org/r/20210513223757.3938-2-bvanassche@acm.org
Link: https://lore.kernel.org/r/20210609033929.3815-11-martin.petersen@oracle.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Reviewed-by: NDamien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: NBenjamin Block <bblock@linux.ibm.com>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Message-Id: <20210609033929.3815-11-martin.petersen@oracle.com>

We are about to remove the request pointer from struct scsi_cmnd and that
will complicate getting to the ref_tag via t10_pi_ref_tag() in the various
drivers. Introduce a helper function to retrieve the reference tag so
drivers will not have to worry about the details.

Link: https://lore.kernel.org/r/20210609033929.3815-2-martin.petersen@oracle.comReviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NBenjamin Block <bblock@linux.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Message-Id: <20210609033929.3815-2-martin.petersen@oracle.com>

Added RHBA and RPA attributes type and length.

As per FC_GC_7 document section "Table 400 – Attribute Entry Types and
associated Values" ASCII type attributes length can be vary from "4 to 256
byte".  If we keep all RHBA ASCII attributes length 256 then total length
is going upto 2750, which is far more than 2048 (max frame size).

In libfc we do have logic to split FCP commands but not for CT commands.
Practically all version/names get covered with in 64 bytes except OS name,
for that we need 128 bytes.  Hence length of all RBHA ASCII attributes
is reduced to 64 bytes and 128 bytes in case of OS name.

RPA attributes total length is within frame size.

Link: https://lore.kernel.org/r/20210603121623.10084-6-jhasan@marvell.comReviewed-by: NHimanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: NJaved Hasan <jhasan@marvell.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Add all attributes for RHBA and RPA registration.

Fallback mechanism is added between RBHA V2 and RHBA V1 attributes. In case
RHBA get fails for V2 attributes we fall back to V1 attribute registration.

Link: https://lore.kernel.org/r/20210603121623.10084-4-jhasan@marvell.comReviewed-by: NHimanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: NJaved Hasan <jhasan@marvell.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

As per the FC-GS-5 specification, attribute lengths of node_name and
manufacturer should in range of "4 to 64 Bytes" only.

Link: https://lore.kernel.org/r/20210603101404.7841-2-jhasan@marvell.com
Fixes: e721eb06 ("scsi: scsi_transport_fc: Match HBA Attribute Length with HBAAPI V2.0 definitions")
CC: stable@vger.kernel.org
Reviewed-by: NHimanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: NJaved Hasan <jhasan@marvell.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Allow the compiler to verify the type of the second argument passed to
scsi_host_complete_all_commands().

Link: https://lore.kernel.org/r/20210524025457.11299-4-bvanassche@acm.org
Cc: Hannes Reinecke <hare@suse.com>
Cc: John Garry <john.garry@huawei.com>
Reviewed-by: NHimanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Make it possible for the compiler to verify whether SAM and host
status codes are used correctly.

[mkp: resolve conflicts with Hannes' SCSI result series]

Link: https://lore.kernel.org/r/20210524025457.11299-3-bvanassche@acm.org
Cc: Hannes Reinecke <hare@suse.com>
Reviewed-by: NJohn Garry <john.garry@huawei.com>
Reviewed-by: NHimanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch prepares for converting SAM status codes into an enum. Without
this patch converting SAM status codes into an enumeration type would
trigger complaints about enum type mismatches for the SAS code.

Link: https://lore.kernel.org/r/20210524025457.11299-2-bvanassche@acm.org
Cc: Hannes Reinecke <hare@suse.com>
Cc: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Cc: Jason Yan <yanaijie@huawei.com>
Reviewed-by: NJohn Garry <john.garry@huawei.com>
Reviewed-by: NHimanshu Madhani <himanshu.madhani@oracle.com>
Acked-by: NJack Wang <jinpu.wang@ionos.com>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

For aborts, qedi needs to cleanup the FW then send the TMF from a worker
thread. While it's doing these the cmd could complete normally and the TMF
could time out. libiscsi would then complete the iscsi_task which will call
into the driver to cleanup the driver level resources while it still might
be accessing them for the cleanup/abort.

This has iscsi_eh_abort keep the iscsi_task ref if the TMF times out, so
qedi does not have to worry about if the task is being freed while in use
and does not need to get its own ref.

Link: https://lore.kernel.org/r/20210525181821.7617-18-michael.christie@oracle.comReviewed-by: NLee Duncan <lduncan@suse.com>
Signed-off-by: NMike Christie <michael.christie@oracle.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

If we haven't done a unbind target call we can race where
iscsi_conn_teardown wakes up the EH thread and then frees the conn while
those threads are still accessing the conn ehwait.

We can only do one TMF per session so this just moves the TMF fields from
the conn to the session. We can then rely on the
iscsi_session_teardown->iscsi_remove_session->__iscsi_unbind_session call
to remove the target and it's devices, and know after that point there is
no device or scsi-ml callout trying to access the session.

Link: https://lore.kernel.org/r/20210525181821.7617-14-michael.christie@oracle.comReviewed-by: NLee Duncan <lduncan@suse.com>
Signed-off-by: NMike Christie <michael.christie@oracle.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

There are a couple places where we could free the iscsi_cls_conn while it's
still in use. This adds some helpers to get/put a refcount on the struct
and converts an exiting user. Subsequent commits will then use the helpers
to fix 2 bugs in the eh code.

Link: https://lore.kernel.org/r/20210525181821.7617-11-michael.christie@oracle.comReviewed-by: NLee Duncan <lduncan@suse.com>
Signed-off-by: NMike Christie <michael.christie@oracle.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Commit 0ab71045 ("scsi: iscsi: Perform connection failure entirely in
kernel space") has the following regressions/bugs that this patch fixes:

1. It can return cmds to upper layers like dm-multipath where that can
retry them. After they are successful the fs/app can send new I/O to the
same sectors, but we've left the cmds running in FW or in the net layer.
We need to be calling ep_disconnect if userspace is not up.

This patch only fixes the issue for offload drivers. iscsi_tcp will be
fixed in separate commit because it doesn't have a ep_disconnect call.

2. The drivers that implement ep_disconnect expect that it's called before
conn_stop. Besides crashes, if the cleanup_task callout is called before
ep_disconnect it might free up driver/card resources for session1 then they
could be allocated for session2. But because the driver's ep_disconnect is
not called it has not cleaned up the firmware so the card is still using
the resources for the original cmd.

3. The stop_conn_work_fn can run after userspace has done its recovery and
we are happily using the session. We will then end up with various bugs
depending on what is going on at the time.

We may also run stop_conn_work_fn late after userspace has called stop_conn
and ep_disconnect and is now going to call start/bind conn. If
stop_conn_work_fn runs after bind but before start, we would leave the conn
in a unbound but sort of started state where IO might be allowed even
though the drivers have been set in a state where they no longer expect
I/O.

4. Returning -EAGAIN in iscsi_if_destroy_conn if we haven't yet run the in
kernel stop_conn function is breaking userspace. We should have been doing
this for the caller.

Link: https://lore.kernel.org/r/20210525181821.7617-8-michael.christie@oracle.com
Fixes: 0ab71045 ("scsi: iscsi: Perform connection failure entirely in kernel space")
Reviewed-by: NLee Duncan <lduncan@suse.com>
Signed-off-by: NMike Christie <michael.christie@oracle.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Subsequent commits allow the kernel to do ep_disconnect. In that case we
will have to get a proper refcount on the ep so one thread does not delete
it from under another.

Link: https://lore.kernel.org/r/20210525181821.7617-7-michael.christie@oracle.comReviewed-by: NLee Duncan <lduncan@suse.com>
Signed-off-by: NMike Christie <michael.christie@oracle.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

During ep_disconnect we have been doing iscsi_suspend_tx/queue to block new
I/O but every driver except cxgbi and iscsi_tcp can still get I/O from
__iscsi_conn_send_pdu() if we haven't called iscsi_conn_failure() before
ep_disconnect. This could happen if we were terminating the session, and
the logout timed out before it was even sent to libiscsi.

Fix the issue by adding a helper which reverses the bind_conn call that
allows new I/O to be queued. Drivers implementing ep_disconnect can use this
to make sure new I/O is not queued to them when handling the disconnect.

Link: https://lore.kernel.org/r/20210525181821.7617-3-michael.christie@oracle.comReviewed-by: NLee Duncan <lduncan@suse.com>
Signed-off-by: NMike Christie <michael.christie@oracle.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This adds a helper to detect if a cmd has completed but is not yet freed.

Link: https://lore.kernel.org/r/20210525181821.7617-2-michael.christie@oracle.comReviewed-by: NLee Duncan <lduncan@suse.com>
Signed-off-by: NMike Christie <michael.christie@oracle.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Originally the SCSI subsystem has been using 'special' SCSI status codes,
which were the SAM-specified ones but shifted by 1.  As most drivers have
now been modified to use the SAM-specified ones, having two nearly
identical sets of definitions only causes confusion.

The Linux-specifed SCSI status codes have been marked obsolete for several
years so drop them and use the SAM-specified status codes throughout.

Link: https://lore.kernel.org/r/20210427083046.31620-41-hare@suse.deReviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NDouglas Gilbert <dgilbert@interlog.com>
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The message byte is now unused, so we can drop the helper to set the
message byte and the check for message bytes during error recovery.

Link: https://lore.kernel.org/r/20210427083046.31620-38-hare@suse.deReviewed-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Add helper to convert message byte into a host byte code.

Link: https://lore.kernel.org/r/20210427083046.31620-18-hare@suse.deReviewed-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Add accessor functions for the host and status byte.

Link: https://lore.kernel.org/r/20210427083046.31620-17-hare@suse.deReviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The driver_byte field in the result is now unused, so we can drop the
definitions.

Link: https://lore.kernel.org/r/20210427083046.31620-15-hare@suse.deReviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Replace the check for DRIVER_SENSE with a check for
scsi_status_is_check_condition().

Audit all callsites to ensure the SAM status is set correctly. For
backwards compability move the DRIVER_SENSE definition to sg.h, and update
sg, bsg, and scsi_ioctl to set the DRIVER_SENSE driver_status whenever
SAM_STAT_CHECK_CONDITION is present.

[mkp: fix zeroday srp warning]

Link: https://lore.kernel.org/r/20210427083046.31620-10-hare@suse.deSigned-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

fix

Add a helper function scsi_status_is_check_condition() to encapsulate the
frequent checks for SAM_STAT_CHECK_CONDITION.

Link: https://lore.kernel.org/r/20210427083046.31620-9-hare@suse.deReviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Introduce scsi_build_sense() as a wrapper around scsi_build_sense_buffer()
to format the buffer and set the correct SCSI status.

Link: https://lore.kernel.org/r/20210427083046.31620-8-hare@suse.deReviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Return the actual error code in __scsi_execute() (which, according to the
documentation, should have happened anyway).  And audit all callers to cope
with negative return values from __scsi_execute() and friends.

[mkp: resolve conflict and return bool]

Link: https://lore.kernel.org/r/20210427083046.31620-7-hare@suse.deReviewed-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>