Add qc->result_tf and ATA_QCFLAG_RESULT_TF.  This moves the
responsibility of loading result TF from post-compltion path to qc
execution path.  qc->result_tf is loaded if explicitly requested or
the qc failsa.  This allows more efficient completion implementation
and correct handling of result TF for controllers which don't have
global TF representation such as sil3124/32.
Signed-off-by: NTejun Heo <htejun@gmail.com>

Make ata_do_reset() deal only with reset.  postreset is now the
responsibility of the caller.  This is simpler and eases later
prereset addition.
Signed-off-by: NTejun Heo <htejun@gmail.com>

Move ->set_mode() handlng into ata_set_mode().
Signed-off-by: NTejun Heo <htejun@gmail.com>

It's not a very good idea to allocate memory during EH.  Use
statically allocated buffer for dev->id[] and add 512byte buffer
ap->sector_buf.  This buffer is owned by EH (or probing) and to be
used as temporary buffer for various purposes (IDENTIFY, NCQ log page
10h, PM GSCR block).
Signed-off-by: NTejun Heo <htejun@gmail.com>

Hold host_set lock while finishing internal qc.
Signed-off-by: NTejun Heo <htejun@gmail.com>

ap->active_tag was cleared in ata_qc_free().  This left ap->active_tag
dangling after ata_qc_complete().  Spurious interrupts inbetween could
incorrectly access the qc.  Clear active_tag in ata_qc_complete().
This change is necessary for later EH changes.
Signed-off-by: NTejun Heo <htejun@gmail.com>

ata_bus_probe() doesn't clear dev->class after ->phy_reset().  This
can result in falsely enabled devices if probing fails.  Clear
dev->class to ATA_DEV_UNKNOWN after fetching it.
Signed-off-by: NTejun Heo <htejun@gmail.com>

While moving ata_scsi_error() from LLDD sht to libata transportt,
EXPORT_SYMBOL_GPL() entry was left out.  Kill it.
Signed-off-by: NTejun Heo <htejun@gmail.com>

AHCI calls ata_dev_classify() even when no device is attached which
results in false class code.  Fix it.
Signed-off-by: NTejun Heo <htejun@gmail.com>

Rename ata_down_sata_spd_limit() and friends to sata_down_spd_limit()
and likewise for simplicity & consistency.
Signed-off-by: NTejun Heo <htejun@gmail.com>

Don't directly access &qc->tf when tf == &qc->tf.
Signed-off-by: NTejun Heo <htejun@gmail.com>

libata needs to invoke EH without scmd.  This patch adds
shost->host_eh_scheduled to implement such behavior.

Currently the only user of this feature is libata and no general
interface is defined.  This patch simply adds handling for
host_eh_scheduled where needed and exports scsi_eh_wakeup() to
modules.  The rest is upto libata.  This is the result of the
following discussion.

http://thread.gmane.org/gmane.linux.scsi/23853/focus=9760

In short, SCSI host is not supposed to know about exceptions unrelated
to specific device or command.  Such exceptions should be handled by
transport layer proper.  However, the distinction is not essential to
ATA and libata is planning to depart from SCSI, so, for the time
being, libata will be using SCSI EH to handle such exceptions.
Signed-off-by: NTejun Heo <htejun@gmail.com>

Introduce scsi_req_abort_cmd(struct scsi_cmnd *).
This function requests that SCSI Core start recovery for the
command by deleting the timer and adding the command to the eh
queue.  It can be called by either LLDDs or SCSI Core.  LLDDs who
implement their own error recovery MAY ignore the timeout event if
they generated scsi_req_abort_cmd.

First post:
http://marc.theaimsgroup.com/?l=linux-scsi&m=113833937421677&w=2Signed-off-by: NLuben Tuikov <ltuikov@yahoo.com>
Signed-off-by: NTejun Heo <htejun@gmail.com>

Adds AHCI support for the VIA VT8251.

Includes a workaround for a hardware bug which requires a Command List
Override before softreset.
Signed-off-by: NBastiaan Jacques <b.jacques@planet.nl>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Any end device that can't support any of the scanning protocols
shouldn't be scanned, so set its id to -1 to prevent
scsi_scan_target() being called for it.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Equivalent of the same patch for the 3w-xxxx driver.
Signed-off-by: NAdam Radford <linuxraid@amcc.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

scsi_kill_request() completes requests via normal SCSI completion path
which decrements busy counts; however, requests which get passed to
scsi_kill_request() aren't holding busy counts and scsi_kill_request()
don't increment them before invoking completion path resulting in
incorrect busy counts.  Bump up busy counts before invoking completion
path.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

As previously reported via Michael Reed, the FC transport took a hit
in 2.6.15 (perhaps a little earlier) when we solved a recursion error.
There are 2 deadlocks occurring:
- With scan and the delete items sharing the same workq, flushing the
  workq for the delete code was getting it stalled behind a very long
  running scan code path.
- There's a deadlock where scsi_remove_target() has to sit behind
  scsi_scan_target() due to contention over the scan_lock().

This patch resolves the 1st deadlock and significantly reduces the
odds of the second. So far, we have only replicated the 2nd deadlock
on a highly-parallel SMP system. More on the 2nd deadlock in a following
email.

This patch reworks the transport to:
- Only use the scsi host workq for scanning
- Use 2 other workq's internally. One for deletions, the other for
  scheduled deletions. Originally, we tried this with a single workq,
  but the occassional flushes of the scheduled queues was hitting the
  second deadlock with a slightly higher frequency. In the future, we'll
  look at the LLDD's and the transport to see if we can get rid of this
  extra overhead.
- When moving to the other workq's we tightened up some object states
  and some lock handling.
- Properly syncs adds/deletes
- minor code cleanups
  - directly reference fc_host_attrs, rather than through attribute
    macros
  - flush the right workq on delayed work cancel failures.

Large kudos to Michael Reed who has been working this issue for the last
month.
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

When a target is added aic79xx tries to be overly clever: it changes
the command on the fly to TEST UNIT READY and tries to requeue the
original command. Sadly this breaks SCSI compability and of course
the midlayer is getting a bit confused by it.

So we're just removing that bit of code and let the midlayer deal with
it. It's clever enough by now. And the driver code is getting simpler.
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

It's no longer needed after the convrsion to use the linux srp.h file.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

As James B. correctly noted, ahd_reset_channel() in
ahd_linux_bus_reset() should be protected by ahd_lock().  However, the
main reason for not doing so was a deadlock with the interesting
polling mechanism to detect the end a bus reset.

This patch replaces the polling mechanism with a saner signalling via
flags; it also gives us the benefit of detecting any multiple calls to
ahd_reset_channel().
Signed-off-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Original From: Ingo Flaschberger <if@xip.at>

To support the RA4100 array from Compaq.

This patch now correctly handles SCSI_UNKNOWN types with regard to
BLIST_REPORTLUNS2 (allow it) and cdb[1] LUN inclusion (don't).

It also allows a BLIST_MAX_512 flag to restrict the maximum transfer
length to 512 blocks (apparently this is an RA4100 problem).
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

When spinlock debugging is turned on, a struct completion grows beyond the
size allowed for the scsi_pointer.  So move the struct completion back onto
the stack.  The additional memory barriers are to keep us from completing
a random piece of kernel stack if the command happens to complete after
the error handling has finished.
Signed-off-by: NMatthew Wilcox <matthew@wil.cx>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Bump ipr driver version to 2.1.3
Signed-off-by: NBrian King <brking@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Encapsulate some more of the device reset processing in
preparation for SATA support.
Signed-off-by: NBrian King <brking@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Remove some unused printk macros, make some more robust, and
convert some to use standard printk macros when possible.
Signed-off-by: NBrian King <brking@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Simplify the dumping of the command status area by
removing some device specific information that has proven
to not be worthwhile.
Signed-off-by: NBrian King <brking@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Fixup a check used by the ipr driver to determine if a given
device is a SCSI disk. Due to the addition of support for
attaching SATA devices, this check needs to be more robust.
Signed-off-by: NBrian King <brking@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Instead of NULLing the resource entry pointer when a disk
goes away to prevent any new commands being sent to it,
set the adapter resource handle to an invalid value so
new ops getting sent to it will fail with a selection timeout
response. This patch is needed for future SATA patches.
Signed-off-by: NBrian King <brking@us.ibm.com>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

when the sg driver is unable to setup direct IO, free that scatter
gather list prior to falling back to indirect IO

Further to this thread started by Bryan Holty:
http://marc.theaimsgroup.com/?l=linux-scsi&m=114306885116728&w=2

Here is the reworked patch again. This time it has been
tested with a program provided by Bryan.
Signed-off-by: NDouglas Gilbert <dougg@torque.net>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

necessary to make the domain class use the internal structures
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

for_each_cpu() actually iterates across all possible CPUs.  We've had mistakes
in the past where people were using for_each_cpu() where they should have been
iterating across only online or present CPUs.  This is inefficient and
possibly buggy.

We're renaming for_each_cpu() to for_each_possible_cpu() to avoid this in the
future.

This patch replaces for_each_cpu with for_each_possible_cpu.
Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Signed-off-by: NMatthew Wilcox <matthew@wil.cx>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

This patch enables clustering and sets max_sectors to 0xffff to enable
reading and writing of large blocks with tapes (and large transfers with
sg). This change is needed after the sg and st drivers started using
chained bios through scsi_request_async() in 2.6.16.
Signed-off-by: NKai Makisara <kai.makisara@kolumbus.fi>
Signed-off-by: NMatthew Wilcox <matthew@wil.cx>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Use wait_for_completion_timeout() instead of using a timer (as
Christoph Hellwig did for aic7xxx).

That lets me eliminate the sym_eh_wait structure; the struct completion,
the old_done pointer and the to_do flag can be folded into the sym_ucmd
(which overrides the scsi_pointer in scsi_cmnd).

The sym_eh_done() function becomes much simpler as the timeout handling
is done in sym_eh_handler() directly.

The host_lock can be unlocked earlier, and I cache the host in
a local variable to make accesses to it quicker.
Signed-off-by: NMatthew Wilcox <matthew@wil.cx>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

The PDC code can set the bus mode, but we were ignoring that setting.
Also move the code that determines bus mode into its own function.
Signed-off-by: NMatthew Wilcox <matthew@wil.cx>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Now sym2 is using spi_print_msg, we don't need to have our own messages
for IGNORE WIDE RESIDUE and MODIFY DATA POINTER, so provide the option
of passing NULL for the label.
Signed-off-by: NMatthew Wilcox <matthew@wil.cx>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Undef SYM_OPT_HANDLE_DEVICE_QUEUEING.
Call sym_put_start_queue instead of sym_start_next_ccbs.
Turn asserts into checks that we can send the command to the adapter,
and return busy from queuecommand if we can't.
Signed-off-by: NMatthew Wilcox <matthew@wil.cx>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

Patch below is one out of a large series to mark kernel data const when
possible, goal is to use .rodata and avoid false sharing
Signed-off-by: NArjan van de Ven <arjan@infradead.org>
Signed-off-by: NMatthew Wilcox <matthew@wil.cx>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

 - to_do was never set to SYM_EH_DO_COMPLETE, so remove that code
 - move the spinlocks inside the common error handler code path
Signed-off-by: NMatthew Wilcox <matthew@wil.cx>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>