Instead of keeping two levels of indirection for requests types, fold it
all into the operations. The little caveat here is that previously
cmd_type only applied to struct request, while the request and bio op
fields were set to plain REQ_OP_READ/WRITE even for passthrough
operations.
Instead this patch adds new REQ_OP_* for SCSI passthrough and driver
private requests, althought it has to add two for each so that we
can communicate the data in/out nature of the request.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Currently the legacy ide driver defines several request types of it's own,
which is in the way of removing that field entirely.
Instead add a type field to struct ide_request and use that to distinguish
the different types of IDE-internal requests.
It's a bit of a mess, but so is the surrounding code..
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jens Axboe <axboe@fb.com>
And require all drivers that want to support BLOCK_PC to allocate it
as the first thing of their private data. To support this the legacy
IDE and BSG code is switched to set cmd_size on their queues to let
the block layer allocate the additional space.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
This removes the request types and hacks from the block code and into the
old IDE driver. There is a small amunt of code duplication due to this,
but it's not too bad.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
These values are only used by the IDE driver, so move them into it
by allowing drivers to take cmd_type values after the first private
one. Note that we have to turn cmd_type into a plain unsigned integer
so that gcc doesn't complain about mismatching enum types.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Replace direct inclusions of <acpi/acpi.h>, <acpi/acpi_bus.h> and
<acpi/acpi_drivers.h>, which are incorrect, with <linux/acpi.h>
inclusions and remove some inclusions of those files that aren't
necessary.
First of all, <acpi/acpi.h>, <acpi/acpi_bus.h> and <acpi/acpi_drivers.h>
should not be included directly from any files that are built for
CONFIG_ACPI unset, because that generally leads to build warnings about
undefined symbols in !CONFIG_ACPI builds. For CONFIG_ACPI set,
<linux/acpi.h> includes those files and for CONFIG_ACPI unset it
provides stub ACPI symbols to be used in that case.
Second, there are ordering dependencies between those files that always
have to be met. Namely, it is required that <acpi/acpi_bus.h> be included
prior to <acpi/acpi_drivers.h> so that the acpi_pci_root declarations the
latter depends on are always there. And <acpi/acpi.h> which provides
basic ACPICA type declarations should always be included prior to any other
ACPI headers in CONFIG_ACPI builds. That also is taken care of including
<linux/acpi.h> as appropriate.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> (drivers/pci stuff)
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> (Xen stuff)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The dev_attrs field of struct bus_type is going away soon, dev_groups
should be used instead. This converts the ide bus code to use the
correct field.
Acked-by: David S. Miller <davem@davemloft.net>
Cc: <linux-ide@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system
Pull "Disintegrate and delete asm/system.h" from David Howells:
"Here are a bunch of patches to disintegrate asm/system.h into a set of
separate bits to relieve the problem of circular inclusion
dependencies.
I've built all the working defconfigs from all the arches that I can
and made sure that they don't break.
The reason for these patches is that I recently encountered a circular
dependency problem that came about when I produced some patches to
optimise get_order() by rewriting it to use ilog2().
This uses bitops - and on the SH arch asm/bitops.h drags in
asm-generic/get_order.h by a circuituous route involving asm/system.h.
The main difficulty seems to be asm/system.h. It holds a number of
low level bits with no/few dependencies that are commonly used (eg.
memory barriers) and a number of bits with more dependencies that
aren't used in many places (eg. switch_to()).
These patches break asm/system.h up into the following core pieces:
(1) asm/barrier.h
Move memory barriers here. This already done for MIPS and Alpha.
(2) asm/switch_to.h
Move switch_to() and related stuff here.
(3) asm/exec.h
Move arch_align_stack() here. Other process execution related bits
could perhaps go here from asm/processor.h.
(4) asm/cmpxchg.h
Move xchg() and cmpxchg() here as they're full word atomic ops and
frequently used by atomic_xchg() and atomic_cmpxchg().
(5) asm/bug.h
Move die() and related bits.
(6) asm/auxvec.h
Move AT_VECTOR_SIZE_ARCH here.
Other arch headers are created as needed on a per-arch basis."
Fixed up some conflicts from other header file cleanups and moving code
around that has happened in the meantime, so David's testing is somewhat
weakened by that. We'll find out anything that got broken and fix it..
* tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system: (38 commits)
Delete all instances of asm/system.h
Remove all #inclusions of asm/system.h
Add #includes needed to permit the removal of asm/system.h
Move all declarations of free_initmem() to linux/mm.h
Disintegrate asm/system.h for OpenRISC
Split arch_align_stack() out from asm-generic/system.h
Split the switch_to() wrapper out of asm-generic/system.h
Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h
Create asm-generic/barrier.h
Make asm-generic/cmpxchg.h #include asm-generic/cmpxchg-local.h
Disintegrate asm/system.h for Xtensa
Disintegrate asm/system.h for Unicore32 [based on ver #3, changed by gxt]
Disintegrate asm/system.h for Tile
Disintegrate asm/system.h for Sparc
Disintegrate asm/system.h for SH
Disintegrate asm/system.h for Score
Disintegrate asm/system.h for S390
Disintegrate asm/system.h for PowerPC
Disintegrate asm/system.h for PA-RISC
Disintegrate asm/system.h for MN10300
...
Remove all #inclusions of asm/system.h preparatory to splitting and killing
it. Performed with the following command:
perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`
Signed-off-by: David Howells <dhowells@redhat.com>
The <linux/device.h> header includes a lot of stuff, and
it in turn gets a lot of use just for the basic "struct device"
which appears so often.
Clean up the users as follows:
1) For those headers only needing "struct device" as a pointer
in fcn args, replace the include with exactly that.
2) For headers not really using anything from device.h, simply
delete the include altogether.
3) For headers relying on getting device.h implicitly before
being included themselves, now explicitly include device.h
4) For files in which doing #1 or #2 uncovers an implicit
dependency on some other header, fix by explicitly adding
the required header(s).
Any C files that were implicitly relying on device.h to be
present have already been dealt with in advance.
Total removals from #1 and #2: 51. Total additions coming
from #3: 9. Total other implicit dependencies from #4: 7.
As of 3.3-rc1, there were 110, so a net removal of 42 gives
about a 38% reduction in device.h presence in include/*
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
The IDE code is still including asm/mutex.h instead of linux/mutex.h
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/ide-2.6:
cmd640: fix kernel oops in test_irq() method
pdc202xx_old: ignore "FIFO empty" bit in test_irq() method
pdc202xx_old: wire test_irq() method for PDC2026x
IDE: pass IRQ flags to the IDE core
ide: fix comment typo in ide.h
bdops->set_capacity() is unnecessarily generic. All that's required
is a simple one way notification to lower level driver telling it to
try to unlock native capacity. There's no reason to pass in target
capacity or return the new capacity. The former is always the
inherent native capacity and the latter can be handled via the usual
device resize / revalidation path. In fact, the current API is always
used that way.
Replace ->set_capacity() with ->unlock_native_capacity() which take
only @disk and doesn't return anything. IDE which is the only current
user of the API is converted accordingly.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Fix typo in the comment to the 'dma_mode' field of the 'struct ide_drive_s'
introduced by the commit 3fccaa192b (ide: add
drive->dma_mode field).
Whilt at it, convert spaces to a tab in the declaration of the neighbouring
'dn' field...
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I noticed that my KVM virtual machines were experiencing IDE
issues resulting in processes stuck on waiting for buffers to
complete.
The root cause is of course race conditions in the ancient qemu
backend that I'm using. However, the fact that the guest isn't
recovering is a bug.
I've tracked it down to the change made last year to dequeue
requests at the start rather than at the end in the IDE layer.
commit 8f6205cd57
Author: Tejun Heo <tj@kernel.org>
Date: Fri May 8 11:53:59 2009 +0900
ide: dequeue in-flight request
The problem is that the function ide_dma_timeout_retry does not
requeue the current request, causing one request to be lost for
each DMA timeout.
This patch fixes this by requeueing the request.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change ->set_dma_mode method parameters to match ->set_dmamode method
used in struct ata_port_operations.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Change ->set_pio_mode method parameters to match ->set_piomode method
used in struct ata_port_operations.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add dma_mode field to ide_drive_t matching dma_mode field used in
struct ata_device.
The validity of the field is restricted to ->dma_pio_mode method
only currently in IDE subsystem.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add pio_mode field to ide_drive_t matching pio_mode field used in
struct ata_device.
The validity of the field is restricted to ->set_pio_mode method
only currently in IDE subsystem.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Based upon a patch by Philippe De Muyter, and feedback from Mark
Lord and Robert Hancock.
As noted by Mark Lord, the outdated ATA1 spec specifies a 20msec
timeout for setting DRQ but lots of common devices overshoot this.
Signed-off-by: David S. Miller <davem@davemloft.net>
->read_proc, ->write_proc are going away, ->proc_fops should be used instead.
The only tricky place is IDENTIFY handling: if for some reason
taskfile_lib_get_identify() fails, buffer _is_ changed and at least
first byte is overwritten. Emulate old behaviour with returning
that first byte to userspace and reporting length=1 despite overall -E.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* Make cmd->tf_flags field 'u16' and add IDE_TFLAG_SET_XFER taskfile flag.
* Update ide_finish_cmd() to set xfer / re-read id if the new flag is set.
* Convert set_xfer_rate() (write handler for /proc/ide/hd?/current_speed)
and ide_cmd_ioctl() (HDIO_DRIVE_CMD ioctl handler) to use the new flag.
* Remove no longer needed disable_irq_nosync() + enable_irq() from
ide_config_drive_speed().
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* Un-static __ide_wait_stat().
* Allow ide_dev_read_id() helper to be called from the IRQ context by
adding irq_ctx flag and using mdelay()/__ide_wait_stat() when needed.
* Switch ide_driveid_update() to set irq_ctx flag.
This change is needed for the consecutive patch which fixes races in
handling of user-space SET XFER commands but for improved bisectability
and clarity it is better to do it in a separate patch.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit 2f0d0fd2a6 ("ide-acpi: cleanup
do_drive_get_GTF()") didn't account for the lack of hwif->acpidata
check in generic_ide_suspend() [ indirect user of do_drive_get_GTF()
through ide_acpi_exec_tfs() ] resulting in broken resume when ACPI
support is enabled but ACPI data is unavailable.
Fix it by adding ide_port_acpi() helper for checking if port needs
ACPI handling and cleaning generic_ide_{suspend,resume}() to use it
instead of hiding hwif->acpidata and ide_noacpi checks in IDE ACPI
helpers (this should help in preventing similar bugs in the future).
While at it:
- kill superfluous debugging printks in ide_acpi_{get,push}_timing()
Reported-and-tested-by: Etienne Basset <etienne.basset@numericable.fr>
Also-reported-and-tested-by: Jeff Chua <jeff.chua.linux@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* Use blk_rq_bytes() instead of obsolete ide_rq_bytes() in ide_kill_rq()
and ide_floppy_do_request() for failed requests.
[ bugfix part ]
* Use blk_rq_bytes() instead of obsolete ide_rq_bytes() in ide_do_devset()
and ide_complete_drive_reset(). Then remove ide_rq_bytes().
[ cleanup part ]
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There are some broken devices that report multiple DMA xfer modes
enabled at once (ATA spec doesn't allow it) but otherwise work fine
with DMA so just delete ide_id_dma_bug().
[ As discovered by detective work by Frans and Bart, due to how
handling of the ID block was handled before commit c419993
("ide-iops: only clear DMA words on setting DMA mode") this
check was always seeing zeros in the fields or other similar
garbage. Therefore this check wasn't actually checking anything.
Now that the tests actually check the real bits, all we see are
devices that trigger the check yet work perfectly fine, therefore
killing this useless check is the best thing to do. -DaveM ]
Reported-by: Frans Pop <elendil@planet.nl>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change ide_drive_t 'drive_data' field from 'unsigned int' type to 'void *'
type, allowing a wider range of values/types to be stored in this field.
Added 'ide_get_drivedata' and 'ide_set_drivedata' helpers to get and set
the 'drive_data' field.
Fixed all host drivers to maintain coherency with the change in the
'drive_data' field type.
Signed-off-by: Joao Ramos <joao.ramos@inov.pt>
[bart: fix qd65xx build, cast to 'unsigned long', minor Coding Style fixups]
Acked-by: Sergei Shtylyov <sshtylyov@ru.montavista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Move the ack_intr() method into 'struct ide_port_ops', also renaming it to
test_irq() while at it...
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Add 'unsigned long port_flags' field to ide_hwif_t.
* Add IDE_PFLAG_PROBING port flag and keep it set during probing.
* Fix ide_pio_need_iordy() to not enable IORDY at a probe time
(IORDY may lead to controller lock up on certain controllers
if the port is not occupied).
Loosely based on the recent libata's fix by Tejun, thanks to Alan
for the hint that IDE may also need it.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Add ide_pio_need_iordy() helper and convert host drivers to use it.
This fixes it8172, it8213, pdc202xx_old, piix, slc90e66 and siimage
host drivers to handle IORDY correctly.
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Add IDE_DFLAG_NIEN_QUIRK device flag and use it instead of
drive->quirk_list.
There should be no functional changes caused by this patch.
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Add ide_check_nien_quirk_list() helper to the core code
and then use it in ide_port_tune_devices().
* Remove no longer needed ->quirkproc methods from hpt366.c
and pdc202xx_{new,old}.c.
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
From the perspective of most users of recent systems, disabling Host
Protected Area (HPA) can break vendor RAID formats, GPT partitions and
risks corrupting firmware or overwriting vendor system recovery tools.
Unfortunately the original (kernels < 2.6.30) behavior (unconditionally
disabling HPA and using full disk capacity) was introduced at the time
when the main use of HPA was to make the drive look small enough for the
BIOS to allow the system to boot with large capacity drives.
Thus to allow the maximum compatibility with the existing setups (using
HPA and partitioned with HPA disabled) we automically disable HPA if
any partitions overlapping HPA are detected. Additionally HPA can also
be disabled using the "nohpa" module parameter (i.e. "ide_core.nohpa=0.0"
to disable HPA on /dev/hda).
v2:
Fix ->resume HPA support.
While at it:
- remove stale "idebus=" entry from Documentation/kernel-parameters.txt
Cc: Robert Hancock <hancockrwd@gmail.com>
Cc: Frans Pop <elendil@planet.nl>
Cc: "Andries E. Brouwer" <Andries.Brouwer@cwi.nl>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
[patch description was based on input from Alan Cox and Frans Pop]
Emphatically-Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Use ->probed_capacity to store native device capacity for ATA disks.
* Add ->set_capacity method to struct ide_disk_ops.
* Implement disk device ->set_capacity method for ATA disks.
* Implement block device ->set_capacity method.
v2:
* Check if LBA and HPA are supported in ide_disk_set_capacity().
* According to the spec the SET MAX ADDRESS command shall be
immediately preceded by a READ NATIVE MAX ADDRESS command.
* Add ide_disk_hpa_{get_native,set}_capacity() helpers.
Together with the previous patch adding ->set_capacity block device
method this allows automatic disabling of Host Protected Area (HPA)
if any partitions overlapping HPA are detected.
Cc: Robert Hancock <hancockrwd@gmail.com>
Cc: Frans Pop <elendil@planet.nl>
Cc: "Andries E. Brouwer" <Andries.Brouwer@cwi.nl>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Emphatically-Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Remove hw_regs_t typedef and rename struct hw_regs_s to struct ide_hw.
There should be no functional changes caused by this patch.
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Pass number of ports to ide_host_{alloc,add}() and then update
all users accordingly.
v2:
- drop no longer needed NULL initializers in buddha.c, cmd640.c and gayle.c
(noticed by Sergei)
There should be no functional changes caused by this patch.
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
* Convert host drivers that still use hw_regs_t's chipset field to use
the one in struct ide_port_info instead.
* Move special handling of ide_pci chipset type from ide_hw_configure()
to ide_init_port().
* Remove chipset field from hw_regs_t.
While at it:
- remove stale comment in delkin_cb.c
There should be no functional changes caused by this patch.
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Replace:
- special_t typedef by IDE_SFLAG_* flags
- 'special_t special' ide_drive_t's field by 'u8 special_flags' one
There should be no functional changes caused by this patch.
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Add ide_check_ireason() function that handles all ATAPI devices.
Reorganize all unlikely cases in ireason checking further down in the
code path.
In addition, add PFX for printks originating from ide-atapi. Finally,
remove ide_cd_check_ireason.
Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Now after all users of pc->buf have been converted, remove the 64B buffer
embedded in each packet command.
There should be no functional change resulting from this patch.
Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
This is in preparation of removing ide_atapi_pc. Expose the buffer as an
argument to ide_queue_pc_tail with later replacing it with local buffer
or even kmalloc'ed one if needed due to stack usage constraints.
Also, add the possibility of passing a NULL-ptr buffer for cmds which
don't transfer data besides the cdb. While at it, switch to local buffer
in idetape_get_mode_sense_results().
There should be no functional change resulting from this patch.
Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Christoph Hellwig