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 <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
They all contain the same thing. Instead, have a single generic one in
include/asm-generic, and permit an arch to override as needed.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Our ATA probe code checks that a device is not reporting a diagnostic
failure during start up. Unfortunately at least one device seems to like
doing this - the Gigabyte iRAM.
This is only done for the master right now (which is fine for the iRAM
as it is SATA), as with PATA some combinations of ATAPI device seem to
fool the check into seeing a drive that isn't there if it is applied to
the slave.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Non-uniform ports handling got broken while updating libata to handle
those in the same host. Only separate irq for the non-uniform
secondary port was implemented while all other fields (host flags,
transfer mode...) of the secondary port simply shared those of the
first.
For ata_piix combined mode, which ATM is the only user of non-uniform
ports, this causes the secondary port assume the wrong type. This can
cause PATA port to use SATA ops, which results in bogus check on PCS
and detection failure.
This patch adds ata_probe_ent->pinfo2 which points to optional
port_info for the secondary port. For the time being, this seems to
be the simplest solution. This workaround will be removed together
with ata_probe_ent itself after init model is updated to allow more
flexibility.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Nelson A. de Oliveira <naoliv@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The vast majority of drivers and changes are from Alan Cox. Albert Lee
contributed and maintains pata_pdc2027x. Adrian Bunk, Andrew Morton,
and Tejun Heo contributed various minor fixes and updates.
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The biggest change is that ata_host_set is renamed to ata_host.
* ata_host_set => ata_host
* ata_probe_ent->host_flags => ata_probe_ent->port_flags
* ata_probe_ent->host_set_flags => ata_probe_ent->_host_flags
* ata_host_stats => ata_port_stats
* ata_port->host => ata_port->scsi_host
* ata_port->host_set => ata_port->host
* ata_port_info->host_flags => ata_port_info->flags
* ata_(.*)host_set(.*)\(\) => ata_\1host\2()
The leading underscore in ata_probe_ent->_host_flags is to avoid
reusing ->host_flags for different purpose. Currently, the only user
of the field is libata-bmdma.c and probe_ent itself is scheduled to be
removed.
ata_port->host is reused for different purpose but this field is used
inside libata core proper and of different type.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The CFA world has some additional rules and drive modes we need to support for
newer expansion cards and on embedded boxes
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Also, moved ATA_MAX_SECTORS and ATA_MAX_SECTORS_LBA48 from
linux/libata.h to linux/ata.h, now that they truly reflect the standard
(well... mostly; note TODO comment).
This changes the performance profile (and potential bug profile)
for a bunch of drivers, so be wary.
Implement dummy port which can be requested by setting appropriate bit
in probe_ent->dummy_port_mask. The dummy port is used as placeholder
for stolen legacy port. This allows libata to guarantee that
index_of(ap) == ap->port_no == actual_device_port_no, and thus to
remove error-prone ap->hard_port_no.
As it's used only when one port of a legacy controller is reserved by
some other entity (e.g. IDE), the focus is on keeping the added *code*
complexity at minimum, so dummy port allocates all libata core
resources and acts as a normal port. It just has all dummy port_ops.
This patch only implements dummy port. The following patch will make
libata use it for stolen legacy ports.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Kill host_set->next
Fix simplex support
Allow per platform setting of IDE legacy bases
Some of this can be tidied further later on, in particular all the
legacy port gunge belongs as a PCI quirk/PCI header decode to understand
the special legacy IDE rules in the PCI spec.
Longer term Jeff also wants to move the request_irq/free_irq out of core
which will make this even cleaner.
tj: folded in three followup patches - ata_piix-fix, broken-arch-fix
and fix-new-legacy-handling, and separated per-dev xfermask into
separate patch preceding this one. Folded in fixes are...
* ata_piix-fix: fix build failure due to host_set->next removal
* broken-arch-fix: add missing include/asm-*/libata-portmap.h
* fix-new-legacy-handling:
* In ata_pci_init_legacy_port(), probe_num was incorrectly
incremented during initialization of the secondary port and
probe_ent->n_ports was incorrectly fixed to 1.
* Both legacy ports ended up having the same hard_port_no.
* When printing port information, both legacy ports printed
the first irq.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Tejun Heo <htejun@gmail.com>
The following patch enhances libata to allow SAS device drivers
to utilize libata to talk to SATA devices. It introduces some
new APIs which allow libata to be used without allocating a
virtual scsi host.
New APIs:
ata_sas_port_alloc - Allocate an ata_port
ata_sas_port_init - Initialize an ata_port (probe device, etc)
ata_sas_port_destroy - Free an ata_port allocated by ata_sas_port_alloc
ata_sas_slave_configure - configure scsi device
ata_sas_queuecmd - queue a scsi command, similar to ata_scsi_queuecomand
These new APIs can be used either directly by a SAS LLDD or could be used
by the SAS transport class.
Possible usage for a SAS LLDD would be:
scsi_scan_host
target_alloc
ata_sas_port_alloc
slave_alloc
ata_sas_port_init
slave_configure
ata_sas_slave_configure
Commands received by the LLDD for SATA devices would call ata_sas_queuecmd.
Device teardown would occur with:
slave_destroy
port_disable
target_destroy
ata_sas_port_destroy
Signed-off-by: Brian King <brking@us.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Update ata_eh_about_to_do() and ata_eh_done() to improve EH action and
EHI flag handling.
* There are two types of EHI flags - one which expires on successful
EH and the other which expires on a successful reset. Make this
distinction clear.
* Unlike other EH actions, reset actions are represented by two EH
action masks and a EHI modifier. Implement correct about_to_do/done
semantics for resets. That is, prior to reset, related EH info is
sucked in from ehi and cleared, and after reset is complete, related
EH info in ehc is cleared.
These changes improve consistency and remove unnecessary EH actions
caused by stale EH action masks and EHI flags.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff 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: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff 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: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff 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: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Separate out __ata_ehi_hotplugged() from ata_ehi_hotplugged(). The
underscored version doesn't set AC_ERR_ATA_BUS. This will be used for
resume which is a hotplug event but not an ATA bus error.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff 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: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff 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: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff 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: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff 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: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Implement ata_port_max_devices(). This function returns the number of
possible devices on a port. This will be used by new PM
implementation.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
From: Andrew Morton <akpm@osdl.org>
s390:
In file included from drivers/scsi/libata-bmdma.c:39: include/linux/libata.h:391: error: field 'sgent' has incomplete type
include/linux/libata.h:392: error: field 'pad_sgent' has incomplete type
include/linux/libata.h: In function 'ata_sg_is_last': include/linux/libata.h:849: error: arithmetic on pointer to an incomplete type
include/linux/libata.h:849: error: arithmetic on pointer to an incomplete type
include/linux/libata.h: In function 'ata_qc_next_sg':
include/linux/libata.h:869: error: increment of pointer to unknown structure
include/linux/libata.h:869: error: arithmetic on pointer to an incomplete type
include/linux/libata.h:869: error: arithmetic on pointer to an incomplete type
include/linux/libata.h:869: error: arithmetic on pointer to an incomplete type
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff 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: Brian King <brking@us.ibm.com>
(with slight merge modifications made by...)
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Currently, the only per-dev EH action is REVALIDATE. EH used to
exploit ehi->dev to do selective revalidation on a ATA bus. However,
this is a bit hacky and makes it impossible to request selective
revalidation from outside of EH or add another per-dev EH action.
This patch adds per-dev EH action mask eh_info->dev_action[] and
update EH to use this field for REVALIDATE. Note that per-dev actions
can still be specified at port-level and it has the same effect of
specifying the action for all devices on the port.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.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: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
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: Tejun 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: Tejun 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: Tejun 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: Tejun Heo <htejun@gmail.com>
Implement ATA part of hotplug. To avoid probing broken devices over
and over again, disabled devices are not automatically detached. They
are detached only if probing is requested for the device or the
associated port is offline. Also, to avoid infinite probing loop,
Each device is probed only once per EH run.
As SATA PHY status is fragile, devices are detached only after it has
used up its recovery chances unless explicitly requested by LLDD or
user (LLDD may request direct detach if, for example, it supports cold
presence detection).
Signed-off-by: Tejun 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: Tejun 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: Tejun 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: Tejun Heo <htejun@gmail.com>
Add device persistent field dev->sdev and store the attached SCSI
device. With hotplug, libata needs to know the attached SCSI device
to offline and detach it, but scsi_device_lookup() cannot be used
because libata will reuse SCSI ID numbers - dead but not gone devices
(due to zombie opens, etc...) interfere with the lookup.
dev->sdev doesn't hold reference to the SCSI device. It's cleared
when the SCSI device goes away.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Add ap->hw_sata_spd_limit and initialize it once during the boot
initialization (or driver load initialization). ap->sata_spd_limit is
reset to ap->hw_sata_spd_limit on hotplug. This prevents spd limits
introduced by earlier devices from affecting new devices.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Lifetimes of some fields span over device plugging/unplugging. This
patch moves such persistent fields to the top of ata_device and
separate them with ATA_DEVICE_CLEAR_OFFSET. Fields above the offset
are initialized once during host initializatino while all other fields
are cleared before hotplugging. Currently ->ap, devno and part of
flags are persistent.
Note that flags is partially cleared while holding host_set lock.
This is to synchronize with later warm plug implementation which will
record hotplug request in dev->flags.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Implement ata_eh_wait(). On return from this function, it's
guaranteed that the EH which was pending or in progress when the
function was called is complete - including the tailing part of SCSI
EH. This will be used by hotplug and others to synchronize with EH.
Signed-off-by: Tejun Heo <htejun@gmail.com>
