1. We don't need to round the SBP-2 segment size limit down to a
   multiple of 4 kB (0xffff -> 0xf000).  It is only necessary to
   ensure quadlet alignment (0xffff -> 0xfffc).

2. Use dma_set_max_seg_size() to tell the DMA mapping infrastructure
   and the block IO layer about the restriction.  This way we can
   remove the size checks and segment splitting in the queuecommand
   path.

   This assumes that no other code in the ieee1394 stack uses
   dma_map_sg() with conflicting requirements.  It furthermore assumes
   that the controller device's platform actually allows us to set the
   segment size to our liking.  Assert the latter with a BUG_ON().

3. Also use blk_queue_max_segment_size() to tell the block IO layer
   about it.  It cannot know it because our scsi_add_host() does not
   point to the FireWire controller's device.

We can also uniformly use dma_map_sg() for the single segment case just
like for the multi segment case, to further simplify the code.

Also clean up how the page table is converted to big endian.

Thanks to Grant Grundler and FUJITA Tomonori for advice.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

Two dma_sync_single_for_cpu() were called in the wrong place.
Luckily they were merely for DMA_TO_DEVICE, hence nobody noticed.

Also reorder the matching dma_sync_single_for_device() a little bit
so that they reside in the same functions as their counterparts.
This also avoids syncing the s/g table for requests which don't use it.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

sbp2 was too quick to report .update() to the ieee1394 core as failed.
(Logged as "Failed to reconnect to sbp2 device!".)  The core would then
unbind sbp2 from the device.

This is not justified if the .update() failed because another bus reset
happened.  We check this and tell the ieee1394 that .update() succeeded,
and the core will call sbp2's .update() for the new bus reset as well.

This improves reconnection/re-login especially on buses with several
disks as they may issue bus resets in close succession when they come
online.

Tested by Damien Benoist.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

This instructs sd_mod to send START STOP UNIT on suspend and resume,
and on driver unbinding or unloading (including when the system is shut
down).

We don't do this though if multiple initiators may log in to the target.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

Reported by Tino Keitel:  PL-3507 with firmware from Prolific does not
spin down the disk on START STOP UNIT with power condition = 0 and start
= 0.  It does however work with power condition = 2 or 3.

Also found while investigating this:  DViCO Momobay CX-1 and FX-3A (TI
TSB42AA9/A based) become unresponsive after START STOP UNIT with power
condition = 0 and start = 0.  They stay responsive if power condition is
set when stopping the motor.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

Boaz Harrosh wrote:
> cmd->cmd_len is now guarantied to be set properly at all cases.
> And some commands you want to support will not be set correctly
> by COMMAND_SIZE().
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

Fix I/O errors due to SYM13FW500's inability to handle larger request
sizes.  Reported by Piergiorgio Sartor <piergiorgio.sartor@nexgo.de> for
firewire-sbp2 in https://bugzilla.redhat.com/show_bug.cgi?id=436879

This fix is necessary because sbp2's default request size limit has been
lifted since 2.6.25-rc1.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: NJarod Wilson <jwilson@redhat.com>

rescan-scsi-bus used to add SBP-2 targets which weren't there.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

Add the same workaround as found in fw-sbp2 for feature parity and
compatibility of the workarounds module parameter.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: NJarod Wilson <jwilson@redhat.com>

sg_dma_len(sg) is invalid before the s/g list is DMA-mapped.

This fixes a post 2.6.24 regression which prevents access to SBP-2
devices on several architectures, introduced by "ieee1394: sbp2: s/g
list access cosmetics", commit 825f1df5.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

This patch speeds up sbp2 a little bit --- but more importantly, it
brings the behavior of sbp2 and fw-sbp2 closer to each other.  Like
fw-sbp2, sbp2 now does not limit the size of single transfers to 255
sectors anymore, unless told so by a blacklist flag or by module load
parameters.

Only very old bridge chips have been known to need the 255 sectors
limit, and we have got one such chip in our hardwired blacklist.  There
certainly is a danger that more bridges need that limit; but I prefer to
have this issue present in both fw-sbp2 and sbp2 rather than just one of
them.

An OXUF922 with 400GB 7200RPM disk on an S400 controller is sped up by
this patch from 22.9 to 23.5 MB/s according to hdparm.  The same effect
could be achieved before by setting a higher max_sectors module
parameter.  On buses which use 1394b beta mode, sbp2 and fw-sbp2 will
now achieve virtually the same bandwidth.  Fw-sbp2 only remains faster
on 1394a buses due to fw-core's gap count optimization.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

Replace sg->length by sg_dma_len(sg).  Rename a variable for shorter
line lengths and eliminate some superfluous local variables.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

This patch relaxes the default SCSI DMA alignment from 512 bytes to 4
bytes.  I remember from previous discussions that usb and firewire have
sector size alignment requirements, so I upped their alignments in the
respective slave allocs.

The reason for doing this is so that we don't get such a huge amount of
copy overhead in bio_copy_user() for udev.  (basically all inquiries it
issues can now be directly mapped).
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

Not architecture specific code should not #include <asm/scatterlist.h>.

This patch therefore either replaces them with
#include <linux/scatterlist.h> or simply removes them if they were
unused.
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

sbp2_host_reset and sbp2_handle_status_write are not serialized against
sbp2_alloc_device and sbp2_remove_device.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

Bug found by Olaf Hering <olh@suse.de>:
sbp2util_remove_command_orb_pool requires a valid lu->hi pointer.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

Revert commit 0555659d from 2.6.22-rc1.
The dma_set_mask call somehow failed on a PowerMac G5, PPC64:
http://lkml.org/lkml/2007/8/1/344

Should there ever occur a DMA mapping beyond the physical DMA range, a
proper SBP-2 firmware will report transport errors.  So let's leave it
at that.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>
Tested-by: NOlaf Hering <olh@suse.de>

This is upwards compatible, except that integer values other than 0 or 1
are no longer accepted.  But values like "Y", "N", "no", "nnoooh!" work
now.

Also, improve a comment on the serialize_io parameter and make the
ORB_SET_EXCLUSIVE macro ultra-safe.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

With "modprobe sbp2 long_ieee1394_id=y", the format of
/sys/bus/scsi/devices/*:*:*:*/ieee1394_id is changed from e.g.
0001041010004beb:0:0 to 0001041010004beb:00042c:0000.

The longer format fully conforms to object identifier sizes as per
SAM(-2...4) and reflects what the SAM target port identifier is meant to
contain:  A Discovery ID allegedly specified by ISO/IEC 13213:1994 ---
however there is no such thing; the authors of SAM probably meant
Directory ID).  Especially target nodes with multiple dynamically added
targets may use Directory IDs to persistently identify target ports.

The new format is independent of implementation details of nodemgr.
Thus the same ieee1394_id attribute format can be implemented in the new
firewire stack.

The ieee1394_id is typically used to create persistently named links in
/dev/disk/by-id.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

- remove the unnecessary map_single path.

- convert to use the new accessors for the sg lists and the
parameters.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: NJames Bottomley <James.Bottomley@SteelEye.com>

drivers/ieee1394/sbp2.c: In function 'sbp2util_access_timeout':
drivers/ieee1394/sbp2.c:399: error: 'TASK_INTERRUPTIBLE' undeclared (first use in this function)
drivers/ieee1394/sbp2.c:399: error: (Each undeclared identifier is reported only once
drivers/ieee1394/sbp2.c:399: error: for each function it appears in.)
drivers/ieee1394/sbp2.c:399: warning: implicit declaration of function 'signal_pending'
drivers/ieee1394/sbp2.c:399: warning: implicit declaration of function 'schedule_timeout'
drivers/ieee1394/sbp2.c: In function 'sbp2_prep_command_orb_sg':
drivers/ieee1394/sbp2.c:1438: warning: implicit declaration of function 'page_address'
drivers/ieee1394/sbp2.c:1438: warning: passing argument 2 of 'dma_map_single' makes pointer from integer without a cast
drivers/ieee1394/sbp2.c: In function 'sbp2_handle_status_write':
drivers/ieee1394/sbp2.c:1842: error: 'TASK_INTERRUPTIBLE' undeclared (first use in this function)

Possibly due to changes in -mm, but this file should explicitly include the
headers for the stuff it uses.
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (brought into alphabetic order)

When the command ORB pool is created, the ORB list won't be accessed
concurrently.  Therefore we don't have to take the spinlock there.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

Unlike the name suggests, "cmd->scatter_gather_element" holds only the
s/g table, not the actual s/g elements.  Since the table is only read
but never written by the device, DMA_BIDIRECTIONAL can be replaced by
DMA_TO_DEVICE which may be cheaper on some architectures.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

In order to use OHCI-1394 physical DMA, all s/g elements, s/g tables,
ORBs, and response buffers have to reside within the first 4 GB of the
FireWire controller's physical address space.  Set the correct mask for
DMA mappings.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

The old setting is copy & waste from usb-storage and doesn't apply to
sbp2.  There is only 4-byte alignment required for everything, except
for S/G table elements which have to be 8-byte aligned according to the
SBP-2 spec.  (They happen to be ____cacheline_aligned in our
implementation.  Whether that's good is another question.)

We now simply don't tune block queue alignment at all.  The default
alignment would surely never become anything else than a multiple of 4,
else tons of calls to blk_queue_dma_alignment would have to be added
everywhere in drivers/...
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

There is no emulation going on here.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

0x000000 could be a valid value to match against, but anything bigger
than 0xffffff cannot.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

Since commit 98e238cd in Linux 2.6.19,
"ieee1394: sbp2: don't prefer MODE SENSE 10", some FireWire DVD-ROMs and
DVD-RWs were mistaken as CD-ROM because sr_mod now sent MODE SENSE 6.
The MMC command set includes only MODE SENSE 10.
http://bugzilla.kernel.org/show_bug.cgi?id=7800

This fix lets sbp2 switch scsi_device.use_10_for_rw on for MMC LUs.
This should rather be done in the command set driver sr_mod, not in the
sbp2 transport driver, and an according patch will follow for a next
Linux release.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

Need to use a PCI device, not a FireWire host device.  Problem found by
Andreas Schwab, mistake pointed out by Benjamin Herrenschmidt.
http://ozlabs.org/pipermail/linuxppc-dev/2006-December/029595.htmlSigned-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>
Tested-by: NAndreas Schwab <schwab@suse.de>

Delete some incorrect code, left over from the initial driver submission
in March 2001.

SBP-2 targets should provide sense data via the SBP-2 status block
(autosense).  We have to pass the REQUEST_SENSE command through to
targets which don't implement autosense, if there are any, and to
accomodate application clients which use this command.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

Merge is finished, can bring the code in readable style again.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

This patch consolidates some bookkeeping for driver registering. It
closely models what pci_register_driver() does. The main addition is
that the owner of the driver is set, so we get a proper symlink
for /sys/bus/ieee1394/driver/*/module.

Also moves setting of name and bus type into nodemgr. Because of this,
we can remove the EXPORT_SYMBOL for ieee1394_bus_type, since it's now
only used in ieee1394.ko.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

API conversion without change in functionality
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>

Move the body of a function into its only caller.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>