commit 54b2b50c20a61b51199bedb6e5d2f8ec2568fb43 upstream.

Some host adapters do not pass commands through to the target disk
directly. Instead they provide an emulated target which may or may not
accurately report its capabilities. In some cases the physical device
characteristics are reported even when the host adapter is processing
commands on the device's behalf. This can lead to adapter firmware hangs
or excessive I/O errors.

This patch disables WRITE SAME for devices connected to host adapters
that provide an emulated target. Driver writers can disable WRITE SAME
by setting the no_write_same flag in the host adapter template.

[jejb: fix up rejections due to eh_deadline patch]
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

all users converted to ->show_info()/->write_info()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

It's still an obsolete interface; don't introduce those in new drivers.
However, it's saner than the ->proc_info() and commits after this one
will convert the existing ->proc_info() users to it.

The read side is ->show_info(seq_file *, struct Scsi_Host *); use
seq_... for generating contents.

The write side is ->write_info(struct Scsi_Host *, char *, int).

Again, this is driven by procfs needs; we are going to kill ->write_proc()
and ->read_proc() and this is the main obstacle to burying that piece of
shit.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

The range checking from fe542396 was bad. We would still end up walking
beyond the array as Type 3 is defined to be 4 in the protection
bitmask. Instead use ARRAY_SIZE() for the range check.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

We set the capacity to zero when we discovered a device formatted with
an unknown DIF protection type. However, the read_capacity code would
override the capacity and cause the device to be enabled regardless.

Make sd_read_protection_type() return an error if the protection type is
unknown. Also prevent duplicate printk lines when the device is being
revalidated.

Reported-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

With previous change, now the ata port runtime suspend will happen as:

disk suspend --> scsi target suspend --> scsi host suspend --> ata port
suspend

ata port(parent device) suspend need to schedule scsi EH which will resume
scsi host(child device). Then the child device resume will in turn make
parent device resume first. This is kind of recursive.

This patch adds a new flag Scsi_Host::eh_noresume.
ata port will set this flag to skip the runtime PM calls on scsi host.

Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

The problem is that if we are doing a scsi scan then the device goes
into recovery then we will wait for the recovery to complete. It waits
because scsi-ml will send inquiries or report luns and the queueing code
will have been blocked due to the host not being ready. However, if we
are in recovery and then a scan is started the scan will silently fail
and some devices will not be added.

It is easy to hit the problem where devices do not show up with
FC where we are doing tests that disrupt the target controllers.
When the controller is disruprted (reboot, or setting firmware, etc),
and we cause the dev loss tmo to fire then devices will be removed
Then when the problem has been fixed, the rport will be scanned and
devices should be added back. But if we cause another disruption before
scanning has started then devices will not get added back. If the problem
is not started until the scan is started then the devices will be added
back.

This patch fixes that problem by not failing scans when the host
is in recovery. We will let scsi-ml send the IO and let the queueing
and scsi error handling deal with it like is done if we went into
recovery while scanning.

For recovery cases where the host is being torn down then with the
patch we will still fail the scan since there is not point in scanning.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

Added new sysfs attr 'host_reset' in scsi_sysfs.c to
perform adapter or firmware reset as suggested by
Mike Christie here:
http://marc.info/?l=linux-scsi&m=127359347111167&w=2

user/application can write "adapter" or "firmware" on
this attr and it will call newly added function hook
in scsi_host_template to call LDD adapter or firmware
reset implementation.

Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>

Move the mid-layer's ->queuecommand() invocation from being locked
with the host lock to being unlocked to facilitate speeding up the
critical path for drivers who don't need this lock taken anyway.

The patch below presents a simple SCSI host lock push-down as an
equivalent transformation.  No locking or other behavior should change
with this patch.  All existing bugs and locking orders are preserved.

Additionally, add one parameter to queuecommand,
	struct Scsi_Host *
and remove one parameter from queuecommand,
	void (*done)(struct scsi_cmnd *)

Scsi_Host* is a convenient pointer that most host drivers need anyway,
and 'done' is redundant to struct scsi_cmnd->scsi_done.

Minimal code disturbance was attempted with this change.  Most drivers
needed only two one-line modifications for their host lock push-down.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Acked-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>