linux-toradex.git/drivers/ide/ide-io.c, branch v2.6.20.10

ide: use correct IDE error recovery

2007-04-13T20:47:05+00:00

ide: use correct IDE error recovery

IDE error recovery is using IDLE IMMEDIATE if the drive is busy or has DRQ set.
This violates the ATA spec (can only send IDLEÃ IMMEDIATE when drive is not
busy) and really hoses up some drives (modern drives will not be able to
recover using this error handling).  The correct thing to do is issue a SRST
followed by a SET FEATURES command.  This is what Western Digital recommends
for error recovery and what Western Digital says Windows does. Ã ItÃ also does
not violate the ATA spec as far as I can tell.

Bart:
* port the patch over the current tree
* undo the recalibration code removal
* send SET FEATURES command after checking for good drive status
* don't check whether the current request is of REQ_TYPE_ATA_{CMD,TASK}
  type because we need to send SET FEATURES before handling any requests
* some pre-ATA4 drives require INITIALIZE DEVICE PARAMETERS command before
  other commands (except IDENTIFY) so send SET FEATURES only if there are
  no pending drive->special requests
* update comments and patch description
* any bugs introduced by this patch are mine and not Suleiman's :-)

Signed-off-by: Suleiman Souhlal 
Acked-by: Alan Cox 
Cc: Chuck Ebbert 
Signed-off-by: Bartlomiej Zolnierkiewicz

ide: clear bmdma status in ide_intr() for ICHx controllers (revised #4)

2007-04-06T10:43:11+00:00

ide: clear bmdma status in ide_intr() for ICHx controllers (revised #4)

patch 1/2 (revised):
- Fix drive->waiting_for_dma to work with CDB-intr devices.
- Do the dma status clearing in ide_intr() and add a new
  hwif->ide_dma_clear_irq for Intel ICHx controllers.

Revised per Alan, Sergei and Bart's advice.

Patch against 2.6.20-rc6. Tested ok on my ICH4 and pdc20275 adapters.
Please review/apply, thanks.

Signed-off-by: Albert Lee 
Cc: Sergei Shtylyov 
Cc: Alan Cox 
Cc: Adam Hawks 
Cc: Chuck Ebbert 
Signed-off-by: Bartlomiej Zolnierkiewicz 
Signed-off-by: Greg Kroah-Hartman

IRQ: Maintain regs pointer globally rather than passing to IRQ handlers

2006-10-05T14:10:12+00:00

Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells 
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)

[PATCH] ide: reprogram disk pio timings on resume

2006-10-03T15:04:08+00:00

Add a step to the IDE PM state machine that reprograms disk PIO timings
as the first step on resume. This prevents ide deadlock on
resume-from-ram on my nforce3-based laptop.

An earlier implementation was written entirely within the amd74xx ide
driver, but Alan helpfully pointed out that this is the correct thing to
do globally. Still, I'm only calling hwif->tuneproc() for disks, based
on two things:

 - The existing state machine is already passed over for non-disk drives
 - Previous testing on my laptop shows that the hangs are related only
   to the disk - suspend/resume from a livecd showed that there's no
   need for this on the cdrom.

Signed-off-by: Jason Lunz 
Cc: Bartlomiej Zolnierkiewicz 
Cc: "Rafael J. Wysocki" 
Cc: Sergei Shtylyov 
Cc: Pavel Machek 
Cc: Brad Campbell 
Cc: David Brownell 
Cc: Alan Cox 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] IDE error handling fixes

2006-10-03T15:04:07+00:00

In 2.6.15.1 I encountered some IDE crashes when unplugging IDE cables to
emulate disk errors.  Below is a patch against 2.6.16 which I think still
applies.

1.  The first BUG_ON could trigger when a PREFLUSH IO fails (it would
   fail the original barrier request which hasn't been marked REQ_STARTED
   yet).

2. the rq could have been dequeued already (same as 1).

3.  HWGROUP(drive)->rq could be NULL because of the ide_error() several
   lines earlier.

Signed-off-by: Hua Zhong 
Cc: Bartlomiej Zolnierkiewicz 
Cc: Alan Cox 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] Remove ->rq_status from struct request

2006-09-30T18:29:23+00:00

After Christophs SCSI change, the only usage left is RQ_ACTIVE
and RQ_INACTIVE. The block layer sets RQ_INACTIVE right before freeing
the request, so any check for RQ_INACTIVE in a driver is a bug and
indicates use-after-free.

So kill/clean the remaining users, straight forward.

Signed-off-by: Jens Axboe

[PATCH] Remove ->waiting member from struct request

2006-09-30T18:29:12+00:00

As the comments indicates in blkdev.h, we can fold it into ->end_io_data
usage as that is really what ->waiting is. Fixup the users of
blk_end_sync_rq().

Signed-off-by: Jens Axboe

[PATCH] Split struct request ->flags into two parts

2006-09-30T18:23:37+00:00

Right now ->flags is a bit of a mess: some are request types, and
others are just modifiers. Clean this up by splitting it into
->cmd_type and ->cmd_flags. This allows introduction of generic
Linux block message types, useful for sending generic Linux commands
to block devices.

Signed-off-by: Jens Axboe

[PATCH] lockdep: annotate on-stack completions

2006-07-03T22:27:09+00:00

lockdep needs to have the waitqueue lock initialized for on-stack waitqueues
implicitly initialized by DECLARE_COMPLETION().  Annotate on-stack completions
accordingly.

Has no effect on non-lockdep kernels.

Signed-off-by: Ingo Molnar 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] lockdep: annotate enable_in_hardirq()

2006-07-03T22:27:09+00:00

Make use of local_irq_enable_in_hardirq() API to annotate places that enable
hardirqs in hardirq context.

Has no effect on non-lockdep kernels.

Signed-off-by: Ingo Molnar 
Signed-off-by: Arjan van de Ven 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds