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)
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>
We need to pass the device in order to do per device checks such as
32bit I/O enables. With the changes to include dev->ap we now don't have
to add parameters however just clean them up. Also add data_xfer methods
to the existing drivers except ata_piix (which is in the other block of
patches). If you reject the piix one just add a data_xfer to it...
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Overriding the whole EH code is a per-transport, not per-host thing.
Move ->eh_strategy_handler to the transport class, same as
->eh_timed_out.
Downside is that scsi_host_alloc can't check for the total lack of EH
anymore, but the transition period from old EH where we needed it is
long gone already.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Rename ATA_FLAG_PORT_DISABLED to ATA_FLAG_DISABLED for consistency.
(ATA_FLAG_* are always about ports).
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
SCSI midlayer has moved hostt->eh_timed_out to transport template. As
libata doesn't need full-blown transport support yet, implement
minimal transport for libata. No transport class or whatsoever, just
empty transport template with ->eh_timed_out hook.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This patch adds support for the Promise FastTrak TX4300/TX4310 4-port PCI SATA
controllers based on the PDC40719 chip.
Signed-off-by: Daniel Drake <dsd@gentoo.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
The previous dev->max_sectors patch made sht->max_sectors meaningless.
Kill all initializations of sht->max_sectors.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
->eng_timeout cannot be invoked with NULL qc anymore. Add an
assertion in ata_scsi_error() and kill NULL qc handling from all
->eng_timeout callbacks.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
This patch adds support for correctly masking out and knowing about
hotplug events on Promise SATAII150 Tx4/Tx2 Plus controllers.
Also, a kmalloc->kzalloc cleanup.
Signed-off-by: Luke Kosewski <lkosewsk@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
Implement ata_eh_qc_complete/retry() using scsi_eh_finish_cmd() and
scsi_eh_flush_done_q(). This removes all eh scsicmd finish hacks from
low level drivers.
This change was first suggested by Jeff Garzik.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
Return AC_ERR_* mask from issue fuctions instead of 0/-1. This
enables things like failing a qc with AC_ERR_HSM when the device
doesn't set DRDY when the qc is about to be issued.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
Reflect changes in SCSI midlayer and updated to use new
ordered request implementation
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <axboe@suse.de>
Some hardware does not support the PACKET command at all.
Other hardware supports ATAPI, but the driver does something nasty such
as calling BUG() when an ATAPI command is issued.
For these such cases, we mark them with a new flag, ATA_FLAG_NO_ATAPI.
Initial version contributed by Ben Collins.
- remove err_mask from the parameter list of the complete functions
- move err_mask to ata_queued_cmd
- initialize qc->err_mask when needed
- for each function call to ata_qc_complete(), replace the err_mask parameter with qc->err_mask.
Signed-off-by: Albert Lee <albertcc@tw.ibm.com>
===============
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
Hi,
the patch below marks several libata (and libata-driver) structures
const so that they end up in the .rodata segment and don't false-share
cachelines with things that get dirtied often.
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
The second argument to ata_qc_complete() was being used for two
purposes: communicate the ATA Status register to the completion
function, and indicate an error. On legacy PCI IDE hardware, the latter
is often implicit in the former. On more modern hardware, the driver
often completely emulated a Status register value, passing ATA_ERR as an
indication that something went wrong.
Now that previous code changes have eliminated the need to use drv_stat
arg to communicate the ATA Status register value, we can convert it to a
mask of possible error classes.
This will lead to more flexible error handling in the future.
I'm using this card in a RAID1 with 2 new SATA drives with no problems.
Card - SATA 300 TX2plus PDC40775 (3d73)
Signed-off-by: Ed Kear <ed@kear.net>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
libata.h:
libata-core:
Add ATA_FLAG_PIO_POLLING flag for LLDs that expect interrupt for
command completion only.
sata_nv.c:
sata_vsc.c:
irq handler is wrapper around ata_host_intr(), can handle PIO interrupts.
sata_promise.c:
sata_sx4.c:
sata_qstor.c:
sata_mv.c:
Private irq handler.
Polling mode ATA_FLAG_PIO_POLLING used for compatibility.
Signed-off-by: Albert Lee <albertcc@tw.ibm.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
- changes license of all code from OSL+GPL to plain ole GPL
- except for NVIDIA, who hasn't yet responded about sata_nv
- copyright holders were already contacted privately
- adds info in each driver about where hardware/protocol docs may be
obtained
- where I have made major contributions, updated copyright dates
Interrupts from devices sharing the same IRQ could cause
ata_host_intr to finish commands being processed by atapi_packet_task
if the commands are using ATA_PROT_ATAPI_NODATA or ATA_PROT_ATAPI_DMA
protocol. This is because libata interrupt handler is unaware that
interrupts are not expected during that period. This patch adds
ATA_FLAG_NOINTR flag to tell the interrupt handler that we're not
expecting interrupts.
Note that once proper HSM is implemented for interrupt-driven PIO,
this should be merged into it and this flag will be removed.
ahci.c is a different kind of beast, so it's left alone.
* The following drivers use ata_qc_issue_prot and ata_interrupt, so
changes in libata core will do.
ata_piix sata_sil sata_svw sata_via sata_sis sata_uli
* The following drivers use ata_qc_issue_prot and custom intr handler.
They need this change to work correctly.
sata_nv sata_vsc
* The following drivers use custom issue function and intr handler.
Currently all custom issue functions don't support ATAPI, so this
change is irrelevant, updated for consistency and to avoid later
mistakes.
sata_promise sata_qstor sata_sx4
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
The Promise TX4200 is a 4-port SATA controller based on the PDC40519 chip. It
meets the description of the 20319, so just a simple ID needs to be added to
support this hardware. Thanks to Martin Povolný for testing.
Signed-off-by: Daniel Drake <dsd@gentoo.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
Otto Meier recently submitted a patch to support the PDC40718 chip (marketed
as SATA300 TX4, a 4-port SATA controller).
Signed-off-by: Otto Meier <gf435@gmx.net>
Signed-off-by: Daniel Drake <dsd@gentoo.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
David Howells