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>
wd33c93_release() has been empty since ages, and sgiwd93.c no longer calls it
since its conversion to a proper platform driver 2 years ago. Also remove the
callers in the m68k wd33c93 shims.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Attached are patches, which help to utilize more of the WD33C93B SCSI
controller's capabilities.
1) Added/changed all the necessary code to enable Burst Mode DMA. Only
Single Byte DMA was used before.
2) Added/changed all the necessary code to enable Fast-10 SCSI transfers.
3) The original driver inadvertently used a transfer period of 1000-800ns
(the lowest possible transfer rate) for asynchronous data transfers,
instead of the (configurable) default period intended for this purpose,
if the target responded to a SDTR not with a Reject-message, but with
a zero-SDTR. This issue was fixed.
Moreover, in case of a Reject the driver used the default-period's
initialization-value instead of its (maybe smaller) current value. The
missing assignment was added.
4) The driver's commandline- and proc-file-interface was augmented to
handle the new options properly.
The WD33C93 manual, found at
http://www.datasheet.in/datasheet-html/W/D/3/WD33C93B_WesternDigital.pdf.html,
was very helpful.
Signed-off-by: peter fuerst <post@pfrst.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
