Commits · f046519fc85a8fdf6a058b4ac9d897cdee6f3e52 · nexedi / linux

19 May, 2008 31 commits

libata: kill hotplug related race condition · f046519f

Tejun Heo authored May 19, 2008

Originally, whole reset processing was done while the port is frozen
and SError was cleared during @postreset().  This had two race
conditions.  1: hotplug could occur after reset but before SError is
cleared and libata won't know about it.  2: hotplug could occur after
all the reset is complete but before the port is thawed.  As all
events are cleared on thaw, the hotplug event would be lost.

Commit ac371987 kills the first race
by clearing SError during link resume but before link onlineness test.
However, this doesn't fix race #2 and in some cases clearing SError
after SRST is a good idea.

This patch solves this problem by cross checking link onlineness with
classification result after SError is cleared and port is thawed.
Reset is retried if link is online but all devices attached to the
link are unknown.  As all devices will be revalidated, this one-way
check is enough to ensure that all devices are detected and
revalidated reliably.

This, luckily, also fixes the cases where host controller returns
bogus status while harddrive is spinning up after hotplug making
classification run before the device sends the first FIS and thus
causes misdetection.

Low level drivers can bypass the logic by setting class explicitly to
ATA_DEV_NONE if ever necessary (currently none requires this).
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

f046519f

libata: move reset freeze/thaw handling into ata_eh_reset() · dc98c32c

Tejun Heo authored May 19, 2008

Previously reset freeze/thaw handling lived outside of ata_eh_reset()
mainly because the original PMP reset code needed the port frozen
while resetting all the fan-out ports, which is no longer the case.

This patch moves freeze/thaw handling into ata_eh_reset().
@prereset() and @postreset() are now called w/o freezing the port
although @prereset() an be called frozen if the port is frozen prior
to entering ata_eh_reset().

This makes code simpler and will help removing hotplug event related
races.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

dc98c32c

libata: reorganize ata_eh_reset() no reset method path · 932648b0

Tejun Heo authored May 19, 2008

Reorganize ata_eh_reset() such that @prereset() is called even when no
reset method is available and if block is used instead of goto to skip
actual reset.  This makes no reset case behave better (readiness wait)
and future changes easier.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

932648b0

libata: fix sata_link_hardreset() @online out parameter handling · 0cbf0711

Tejun Heo authored May 19, 2008

The @online out parameter is supposed to set to true iff link is
online and reset succeeded as advertised in the function description
and callers are coded expecting that.  However, sata_link_reset()
didn't behave this way on device readiness test failure.  Fix it.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

0cbf0711

sata_promise: other cleanups · 7715a6f9

Mikael Pettersson authored May 17, 2008

Minor coding-style fixes for sata_promise:
- remove stray blank lines
- fix checkpatch.pl errors; warnings about long lines
  remain, but I don't intend to address those at this time
- remove two inline directives: neither is essential and
  both functions are trivially inlinable anyway by virtue
  of being static and having a single unique call site
- fix comment in pdc_interrupt(): the bits in PDC_INT_SEQMASK
  denote SEQIDs not tags, the distinction becomes important
  when NCQ gets implemented
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

7715a6f9

sata_promise: mmio access cleanups · 821d22cd

Mikael Pettersson authored May 17, 2008

This patch cleans up sata_promise's mmio accesses.

In sata_promise there are three distinct mmio address spaces:
1. global registers, offsets from host->iomap[PDC_MMIO_BAR]
2. per-port ATA registers, offsets from ap->ioaddr.cmd_addr
3. per-port SATA registers, offsets from ap->ioaddr.scr_addr

The driver currently often fails to indicate which address space
a given mmio base pointer refers to, which is a source of bugs
and confusion (see recent pdc_thaw() irq clearing bug; it's also
been an obstacle for the pending NCQ extensions).

To reduce these problems, adopt a coding style where the name of
a base pointer always indicates which address space it refers to:
1. global registers: host_mmio
2. per-port ATA registers: ata_mmio
3. per-port SATA registers: sata_mmio

Also rearrange register offset definitions to clearly indicate
which address space they belong to, and add a symbolic definition
for the previously hard-coded PHYMODE4 register.
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

821d22cd

sata_promise: fix irq clearing buglets · a13db78e

Mikael Pettersson authored May 17, 2008

This patch fixes two bugs in sata_promise's irq status clearing paths:
1. When clearing the irq status for a specific port, the driver
   read the global SEQMASK register. This is wrong because that
   clears the irq status for _all_ ports.
2. pdc_thaw() incorrectly added the PDC_INT_SEQMASK host register
   offset to a per-port ata engine base address. This resulted in
   it reading the unrelated PDC_PKT_SUBMIT register, which did not
   have the desired irq status clearing effect.

In both cases the fix is to read from the port's Command/Status
register. This also matches what Promise's own driver does.
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

a13db78e

ata: remove FIT() macro · 07633b5d

Harvey Harrison authored May 14, 2008

Use the kernel-provided clamp_val() macro.

FIT was always applied to a member of struct ata_timing (unsigned short)
and two constants.  clamp_val will not cast to short anymore.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

07633b5d

sata_mv: ensure empty request queue for FBS-NCQ EH · 06aaca3f

Mark Lord authored May 19, 2008

Check for an empty request queue before stopping EDMA after a FBS-NCQ error,
as per recommendation from the Marvell datasheet.

This ensures that the EDMA won't suddenly become active again
just after our subsequent check of the empty/idle bits.

Also bump DRV_VERSION.
Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>