On some platforms the hard-casting of 8 byte node_name and
port_name arrays to an u64 would cause unaligned-access
warnings.  Generalize the conversions with a transport
helper function which performs consistent shifting of WWN
bytes.
Signed-off-by: NAndrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

The SAS transport class contains common code to deal with SAS HBAs, an
aproximated representation of SAS topologies in the driver model,
and various sysfs attributes to expose these topologies and managment
interfaces to userspace.

In addition to the basic SCSI core objects this transport class introduces
two additional intermediate objects:  The SAS PHY as represented by struct
sas_phy defines an "outgoing" PHY on a SAS HBA or Expander, and the SAS
remote PHY represented by struct sas_rphy defines an "incoming" PHY on a
SAS Expander or end device.  Note that this is purely a software concept, the
underlying hardware for a PHY and a remote PHY is the exactly the same.

There is no concept of a SAS port in this code, users can see what PHYs
form a wide port based on the port_identifier attribute, which is the same
for all PHYs in a port.

This submission doesn't handle hot-plug addition or removal of SAS devices
and thus doesn't do scanning in a workqueue yet, that will be added in
phase2 after this submission.  In a third phase I will add additional
managment infrastructure.

I think this submission is ready for 2.6.14, but additional comments are
of course very welcome.

I'd like to thanks James Smart a lot for his very useful input on the
design.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

This one removes struct scsi_request entirely from sd.  In the process,
I noticed we have no callers of scsi_wait_req who don't immediately
normalise the sense, so I updated the API to make it take a struct
scsi_sense_hdr instead of simply a big sense buffer.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

This one's slightly more difficult.  The transport class uses
REQ_FAILFAST, so another interface (scsi_execute) had to be invented to
take the extra flag.  Also, the sense functions are shifted around to
allow spi_execute to place data directly into a struct scsi_sense_hdr.
With this change, there's probably a lot of unnecessary sense buffer
allocation going on which we can fix later.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

After this, we just have some drivers, all the ULDs and the SPI
transport class using scsi_wait_req().
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Original From: Mike Christie <michaelc@cs.wisc.edu>

Add scsi_execute_req() as a replacement for scsi_wait_req()

Fixed up various pieces (added REQ_SPECIAL and caught req use after
free)
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

This patch is necessary if we begin exposing underlying physical disks
(which can attach to the SPI transport class) of the hardware RAID
cards, since we don't want any SPI parameters binding to the RAID
devices.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

We have some nasty issues with 2.6.12-rc6. Any request to scan on
the lpfc or qla2xxx FC adapters will oops. What is happening is the
system is defaulting to non-transport registered targets, which
inherit the parent of the scan. On this second scan, performed by
the attribute, the parent becomes the shost instead of the rport.
The slave functions in the 2 FC adapters use starget_to_rport()
routines, which incorrectly map the shost as an rport pointer.

Additionally, this pointed out other weaknesses:
- If the target structure is torn down outside of the transport,
  we have no method for it to be regenerated at the proper parent.
- We have race conditions on the target being allocated by both
  the midlayer scan (parent=shost) and by the fc transport
  (parent=rport).
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

There are certain rogue devices (and the aic7xxx driver) that return
BUSY or QUEUE_FULL forever.  This code will apply a global timeout (of
the total number of retries times the per command timer) to a given
command.  If it is exceeded, the command is completed regardless of its
state.

The patch also removes the unused field in the command: timeout and
timeout_total.

This solves the problem of detecting an endless loop in the mid-layer
because of BUSY/QUEUE_FULL bouncing, but will not recover the device.
In the aic7xxx case, the driver can be recovered by sending a bus reset,
so possibly this should be tied into the error handler?
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

This parameter is important only to people who take the time to tune the
margin control settings, otherwise it's completely irrelevant.  However,
just in case anyone should want to do this, it's appropriate to include
the parameter.

I don't do anything with it in DV by design, so the parameter will come
up as off by default, so if anyone actually wants to play with the
margin control settings they'll have to enable it under the
spi_transport class first.

I also updated the transfer settings display to report all of the PPR
settings instead of only DT, IU and QAS
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Fixes up some warnings in the tree.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Add support to not allow additions to a host when it is being removed.
Signed-off-by: NMike Anderson <andmike@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Migrate the current SCSI host state model to a model like SCSI
device is using.
Signed-off-by: NMike Anderson <andmike@us.ibm.com>

Rejections fixed up and
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

int_to_scsilun() takes a pointer to a struct scsi_lun in it's
prototype, so add this structure to scsi_device.h to avoid declaration
inside function prototype warnings.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

One of the issues we had was reverting the midlayers lun value
into the 8byte lun value that we wanted to send to the device.
Historically, there's been some combination of byte swapping,
setting high/low, etc. There's also been no common thread between
how our driver did it and others.  I also got very confused as
to why byteswap routines were being used.

Anyway, this patch is a LLDD-callable function that reverts the
midlayer's lun value, stored in an int, to the 8-byte quantity
(note: this is not the real 8byte quantity, just the same amount
that scsilun_to_int() was able to convert and store originally).

This also solves the dilemma of the thread:
http://marc.theaimsgroup.com/?l=linux-kernel&m=112116767118981&w=2

A patch for the lpfc driver to use this function will be along
in a few days (batched with other patches).
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Here's a tiny update that means we print the correct ASCII type
information
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

We never look at it except for the old megaraid driver that abuses it
for sending internal commands.  That usage can be fixed easily because
those internal commands are single-threaded by a mutex and we can easily
use a completion there.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

never checked anywhere
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Never used for anything but printing it out in debug routines.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

it's never set to anything, and just three broken drivers are looking
at it and doing odd things.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

scsi_add_host is the proper place to set the device, but people copy
the scsi_set_device usage from older drivers again and again.

note that this leaves some legacy drivers like qlogicisp/qlogicfc
without pci association in sysfs, but they're scheduled to go away soon
anyway.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Changes:
 - Provide SG_IO access to BLOCK and EXECUTIVE class on Adaptec
   controllers
 - Use PRIVATE messages in SCSI-OSM because on some controllers normal
   SCSI class commands like READ or READ CAPACITY cause errors
 - Use new DMA and SG list creation function
 - Added workaround to limit sectors per request for Adaptec 2400A
   controllers
Signed-off-by: NMarkus Lidel <Markus.Lidel@shadowconnect.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch basically allows any HBA attached to the SPI transport class
to declare an extra area which the mid-layer will allocate as part of
its device and target allocations.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

This gives the HBA driver notice when a target is created and
destroyed to allow it to manage its own target based allocations
accordingly.

This is a much reduced verson of the original patch sent in by
James.Smart@Emulex.com
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

	a) TYPE_SDAD renamed to TYPE_RBC and taken to scsi.h
	b) in sbp2.c remapping of TYPE_RPB to TYPE_DISK turned off
	c) relevant places in midlayer and sd.c taught to accept TYPE_RBC
	d) sd.c::sd_read_cache_type() looks into page 6 when dealing with
TYPE_RBC - these guys have writeback cache flag there and are not guaranteed
to have page 8 at all.
	e) sd_read_cache_type() got an extra sanity check - it checks that
it got the page it asked for before using its contents.  And screams if
mismatch had happened.  Rationale: there are broken devices out there that
are "helpful" enough to go for "I don't have a page you've asked for, here,
have another one".  For example, PL3507 had been caught doing just that...
	f) sbp2 sets sdev->use_10_for_rw and sdev->use_10_for_ms instead
of bothering to remap READ6/WRITE6/MOD_SENSE, so most of the conversions
in there are gone now.

	Incidentally, I wonder if USB storage devices that have no
mode page 8 are simply RBC ones.  I haven't touched that, but it might
be interesting to check...
Signed-off-by: NAl Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

There's a basic need not to have parameters go under or over certain
values when doing domain validation.  The basic ones are

max_offset, max_width and min_period

This patch makes the transport class take and enforce these three
limits.  Currently they can be set by the user, although they could
obviously be read from the HBA's on-board NVRAM area during
slave_configure (if it has one).
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

This patch adds a device driver for scsi media changer devices.
Signed-off-by: NGerd Knorr <kraxel@bytesex.org>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

This patch removes volatile qualifier from scsi_device->device_busy,
Scsi_Host->host_busy and ->host_failed as the volatile qualifiers
don't serve any purpose now.  While at it, convert those fields from
unsigned short to unsigned int as suggested by Christoph.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

We have a DID_IMM_RETRY to require a retry at once, but we could do with
a DID_REQUEUE to instruct the mid-layer to treat this command in the
same manner as QUEUE_FULL or BUSY (i.e. halt the submission until
another command returns ... or the queue pressure builds if there are no
outstanding commands).
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

scsi_cmnd->serial_number_at_timeout doesn't serve any purpose
anymore.  All serial_number == serial_number_at_timeout tests
are always true in abort callbacks.  Kill the field.  Also, as
->pid always equals ->serial_number and ->serial_number
doesn't have any special meaning anymore, update comments
above ->serial_number accordingly.  Once we remove all uses of
this field from all lldd's, this field should go.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

scsi_cmnd->internal_timeout field doesn't have any meaning
anymore.  Kill the field.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Adapted from a patch in SuSE's kernel SRPM.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

We have a DID_IMM_RETRY to require a retry at once, but we could do with
a DID_REQUEUE to instruct the mid-layer to treat this command in the
same manner as QUEUE_FULL or BUSY (i.e. halt the submission until
another command returns ... or the queue pressure builds if there are no
outstanding commands).
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

scsi_cmnd->serial_number_at_timeout doesn't serve any purpose
anymore.  All serial_number == serial_number_at_timeout tests
are always true in abort callbacks.  Kill the field.  Also, as
->pid always equals ->serial_number and ->serial_number
doesn't have any special meaning anymore, update comments
above ->serial_number accordingly.  Once we remove all uses of
this field from all lldd's, this field should go.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

scsi_cmnd->internal_timeout field doesn't have any meaning
anymore.  Kill the field.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Adapted from a patch in SuSE's kernel SRPM.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

- add a comment to the device structure that the device_busy field
  is now protected by the request_queue->queue_lock
- null out sdev->request_queue after the queue is released to trap
  any (and there shouldn't be any) use after the queue is freed.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

The current problem seen is that the queue lock is actually in the
SCSI device structure, so when that structure is freed on device
release, we go boom if the queue tries to access the lock again.

The fix here is to move the lock from the scsi_device to the queue.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>