In the error path, ata_device_add()

* dereferences null host_set->ports[] element.
* calls scsi_remove_host() on not-yet-added shost.

This patch fixes both bugs.  The first problem was spotted and initial
patch submitted by Dave Jones <davej@redhat.com>.  The second problem
was mentioned and fixed by Jeff Garzik <jgarzik@pobox.com> in a larger
cleanup patch.

Cc: Dave Jones <davej@redhat.com>
Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: NTejun Heo <htejun@gmail.com>

(tj: this is for the following ata_device_add() fix)
Signed-off-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NTejun Heo <htejun@gmail.com>

ata_prot_detach() did nothing for old EH ports and thus SCSI hosts
associated with those ports are left dangling after they are detached
leaving stale devices and causing oops eventually.  Make
ata_port_detach() remove SCSI hosts for old EH ports.
Signed-off-by: NTejun Heo <htejun@gmail.com>

This one looks better, IMHO.

This restores the default libata configuration messages printed during booting.

Signed-off-by: <petkov@math.uni-muenster.de>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Reimplement controller-wide PM.  ata_host_set_suspend/resume() are
defined to suspend and resume a host_set.  While suspended, EHs for
all ports in the host_set are pegged using ATA_FLAG_SUSPENDED and
frozen.

Because SCSI device hotplug is done asynchronously against the rest of
libata EH and the same mutex is used when adding new device, suspend
cannot wait for hotplug to complete.  So, if SCSI device hotplug is in
progress, suspend fails with -EBUSY.

In most cases, host_set resume is followed by device resume.  As each
resume operation requires a reset, a single host_set-wide resume
operation may result in multiple resets.  To avoid this, resume waits
upto 1 second giving PM to request resume for devices.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Reimplement per-dev PM.  The original implementation directly put the
device into suspended mode and didn't synchronize w/ EH operations
including hotplug.  This patch reimplements ata_scsi_device_suspend()
and ata_scsi_device_resume() such that they request EH to perform the
respective operations.  Both functions synchronize with hotplug such
that it doesn't operate on detached devices.

Suspend waits for completion but resume just issues request and
returns.  This allows parallel wake up of devices and thus speeds up
system resume.

Due to sdev detach synchronization, it's not feasible to separate out
EH requesting from sdev handling; thus, ata_device_suspend/resume()
are removed and everything is implemented in the respective
libata-scsi functions.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Implement two PM per-dev EH actions - ATA_EH_SUSPEND and
ATA_EH_RESUME.  Each action puts the target device into suspended mode
and resumes from it respectively.

Once a device is put to suspended mode, no EH operations other than
RESUME is allowed on the device.  The device will stay suspended till
it gets resumed and thus reset and revalidated.  To implement this, a
new device state helper - ata_dev_ready() - is implemented and used in
EH action implementations to make them operate only on attached &
running devices.

If all possible devices on a port are suspended, reset is skipped too.
This prevents spurious events including hotplug events from disrupting
suspended devices.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Implement ATA_EHI_NO_AUTOPSY and QUIET.  These used to be implied by
ATA_PFLAG_LOADING, but new power management and PMP support need to
use these separately.  e.g. Suspend/resume operations shouldn't print
full EH messages and resume shouldn't be recorded as an error.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

The names of predefined debounce timing parameters didn't exactly
match their usages.  Rename to more generic names and implement param
selection helper sata_ehc_deb_timing() which uses EHI_HOTPLUGGED to
select params.

Combined with the previous EHI_RESUME_LINK differentiation, this makes
parameter selection accurate.  e.g. user scan resumes link but normal
deb param is used instead of hotplug param.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Implement ATA_EHI_RESUME_LINK, which indicates that the link needs to
be resumed.  This used to be implied by ATA_EHI_HOTPLUGGED.  However,
hotplug isn't the only event which requires link resume and separating
this out allows other places to request link resume.  This
differentiation also allows better debounce timing selection.

This patch converts user scan to use ATA_EHI_RESUME_LINK.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

ap->flags is way too clamped.  Separate out core dynamic flags to
ap->pflags.  ATA_FLAG_DISABLED is a dynamic flag but left alone as
it's referenced by a lot of LLDs and it's gonna be removed once all
LLDs are converted to new EH.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

In preparation for SAS attached SATA devices, which will
not have a libata scsi_host, only setup host->max_cmd_len
if ap->host exists.
Signed-off-by: NBrian King <brking@us.ibm.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

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: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NJörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>

locking init cleanups:

 - convert " = SPIN_LOCK_UNLOCKED" to spin_lock_init() or DEFINE_SPINLOCK()
 - convert rwlocks in a similar manner

this patch was generated automatically.

Motivation:

 - cleanliness
 - lockdep needs control of lock initialization, which the open-coded
   variants do not give
 - it's also useful for -rt and for lock debugging in general
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Cosmetic updates in libata-core.c.

* trim trailing whitespaces
* break lines which are over 80 column
* kill unnecessary braces
* make indentation consistent
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

From: Andrew Morton <akpm@osdl.org>

Provide a module parameter to override the default 30-second-per-device SATA
probing timeout.

Cc: Tejun Heo <htejun@gmail.com>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Make ata_do_simple_cmd() and ata_flush_cache() global.  These will be
used from libata-eh.c.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

* the function has always returned AC_ERR_* masks not -errno but its
  return type was int.  Make return type unsigned int.

* don't print error message automatically.  it's the caller's
  responsibility.

* add header comment
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Move ata_do_simple_cmd() below ata_exec_internal() for consistency.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

The first 25% of libata-core.c converted to the new debugging scheme.

Signed-off-by: <petkov@math.uni-muenster.de>

(with addition of ATA_MSG_WARN to standard msg_enable by me)
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Prepare for changes required to support SATA devices
attached to SAS HBAs. For these devices we don't want to
use host_set at all, since libata will not be the owner
of struct scsi_host.
Signed-off-by: NBrian King <brking@us.ibm.com>

(with slight merge modifications made by...)
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Move the DMA blacklisting of the CDB-intr devices
from ata_check_atapi_dma() to ata_dma_blacklisted(), where it makes more sense.
Signed-off-by: NAlbert Lee <albertcc@tw.ibm.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Doing a full ata_busy_sleep() seems to get suspend and resume working
fine on the Apple Mac Mini, at least.
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

For a legacy ATA controller, libata registers two separate host sets.
There was no connection between the two hosts making it impossible to
traverse all ports related to the controller.  This patch adds
host_set->next which points to the second host_set and makes
ata_pci_remove_one() remove all associated host_sets.

* On device removal, all ports hanging off the device are properly
  detached.  Prior to this patch, ports on the first host_set weren't
  detached casuing oops on driver unloading.

* On device removal, both host_sets are properly freed

This will also be used by new power management code to suspend and
resume all ports of a controller.  host_set/port representation will
be improved to handle legacy controllers better and this host_set
linking will go away with it.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Add RETURNS comment above ata_exec_internal() and kill extra blank
line.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

This patch makes libata snoop 'SET FEATURES - WRITE CACHE
ENABLE/DISABLE' command, executing requisite revalidation processes
to update cached data.
Signed-off-by: NForrest Zhao <forrest.zhao@intel.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Suggested by Jarek P.

Setup nbytes in ata_sg_init_one to the total transfer length
of the command. This is needed by some HBAs that need to know
the total transfer length of each command.
Signed-off-by: NBrian King <brking@us.ibm.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Signed-off-by: <petkov@uni-muenster.de>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

With ops->probe_init() gone, no user is left in libata-core.c.  Move
ata_do_reset() to libata-eh.c and make it static.
Signed-off-by: NTejun Heo <htejun@gmail.com>

Now that all drivers implementing new EH are converted to new probing
mechanism, ops->probe_reset doesn't have any user.  Kill it.
Signed-off-by: NTejun Heo <htejun@gmail.com>

Update unload unplug - driver unloading / PCI removal.  This is done
by ata_port_detach() which short-circuits EH, disables all devices and
freezes the port.  With this patch, EH and unloading/unplugging are
properly synchronized.
Signed-off-by: NTejun Heo <htejun@gmail.com>

Implement bootplug - boot probing via hotplug path.  While loading,
ata_host_add() simply schedules probing and invokes EH.  After EH
completes, ata_host_add() scans and assicates them with SCSI devices.
EH path is slightly modified to handle this (e.g. no autopsy during
bootplug).  The SCSI part is left in ata_host_add() because it's
shared with legacy path and to keep probing order as before (ATA scan
all ports in host_set then attach all).
Signed-off-by: NTejun Heo <htejun@gmail.com>

Implement warmplug.  User-initiated unplug can be detected by
hostt->slave_destroy() and plug by transportt->user_scan().  This
patch only implements the two callbacks.  The next function will hook
them.
Signed-off-by: NTejun Heo <htejun@gmail.com>

Implement SCSI part of hotplug.

This must be done in a separate context as SCSI makes use of EH during
probing.  SCSI scan fails silently if EH is in progress.  In such
cases, libata pauses briefly and retries until every device is
attached.
Signed-off-by: NTejun Heo <htejun@gmail.com>

ata_hsm_move() will be used by LLDDs which depend on standard PIO HSM
but implement their own interrupt handlers.
Signed-off-by: NTejun Heo <htejun@gmail.com>

With hotplug, every reset might be a probing reset and thus something
similar to probe_init() is needed.  prereset() method is called before
a series of resets to a port and is the counterpart of postreset().
prereset() can tell EH to use different type of reset or skip reset by
modifying ehc->i.action.

This patch also implements ata_std_prereset().  Most controllers
should be able to use this function directly or with some wrapping.
After hotplug, different controllers need different actions to resume
the PHY and detect the newly attached device.  Controllers can be
categorized as follows.

* Controllers which can wait for the first D2H FIS after hotplug.
  Note that if the waiting is implemented by polling TF status, there
  needs to be a way to set BSY on PHY status change.  It can be
  implemented by hardware or with the help of the driver.

* Controllers which can wait for the first D2H FIS after sending
  COMRESET.  These controllers need to issue COMRESET to wait for the
  first FIS.  Note that the received D2H FIS could be the first D2H
  FIS after POR (power-on-reset) or D2H FIS in response to the
  COMRESET.  Some controllers use COMRESET as TF status
  synchronization point and clear TF automatically (sata_sil).

* Controllers which cannot wait for the first D2H FIS reliably.
  Blindly issuing SRST to spinning-up device often results in command
  issue failure or timeout, causing extended delay.  For these
  controllers, ata_std_prereset() explicitly waits ATA_SPINUP_WAIT
  (currently 8s) to give newly attached device time to spin up, then
  issues reset.  Note that failing to getting ready in ATA_SPINUP_WAIT
  is not critical.  libata will retry.  So, the timeout needs to be
  long enough to spin up most devices.

LLDDs can tell ata_std_prereset() which of above action is needed with
ATA_FLAG_HRST_TO_RESUME and ATA_FLAG_SKIP_D2H_BSY flags.  These flags
are PHY-specific property and will be moved to ata_link later.

While at it, this patch unifies function typedef's such that they all
have named arguments.
Signed-off-by: NTejun Heo <htejun@gmail.com>

With hotplug, PHY always needs to be debounced before a reset as any
reset might find new devices.  Extract PHY waiting code from
sata_phy_resume() and extend it to include SStatus debouncing.  Note
that sata_phy_debounce() is superset of what used to be done inside
sata_phy_resume().

Three default debounce timing parameters are defined to be used by
hot/boot plug.  As resume failure during probing will be properly
handled as errors, timeout doesn't have to be long as before.
probeinit() uses the same timeout to retain the original behavior.
Signed-off-by: NTejun Heo <htejun@gmail.com>