Commit Graph

126202 Commits

Author SHA1 Message Date
Sergei Shtylyov 05789634ef ide-dma-sff: factor out ide_dma_sff_write_status()
Factor out ide_dma_sff_write_status(), symmetric to ide_dma_sff_read_status().

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:21:02 +01:00
Sergei Shtylyov 592b531521 ide: move read_sff_dma_status() method to 'struct ide_dma_ops'
Move apparently misplaced read_sff_dma_status() method from 'struct ide_tp_ops'
to 'struct ide_dma_ops', renaming it to dma_sff_read_status() and making only
required for SFF-8038i compatible IDE controller drivers (greatly cutting down
the number of initializers) as its only user (outside ide-dma-sff.c and such
drivers) appears to be ide_pci_check_simplex() which is only called for such
controllers...

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:21:02 +01:00
Sergei Shtylyov 3f023b0138 ide: don't set hwif->dma_ops in init_dma() method
Replace setting of 'hwif->dma_ops' in the 'alim15x3' and 'palm_bk3710' drivers'
init_dma() methods with initializing the corresponding member of their 'struct
ide_port_info' instances and remove such setting from the 'hpt366' driver that
just doesn't use 'sff_dma_ops'. Along with some code save, this prepares us for
the next patch...

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:21:01 +01:00
Shane McDonald 391ad1908a Resurrect IT8172 IDE controller driver
Support for the IT8172 IDE controller was removed from the kernel
sometime after 2.6.18.  Support for the only boards that used the IT8172
was removed from the kernel after 2.6.18, as they had never compiled
since 2.6.0.  However, there are a couple of platforms that use this
chip: the PMC-Sierra Xiao Hu thin-client computer, which is no longer
in production, and the Linksys NSS4000 Network Attached Storage box,
which is based on the Xiao Hu board.  I am attempting to add support
for the Xiao Hu to the kernel, and this IT8172 IDE controller is the
first bit of code in this effort.

This patch resurrects the IT8172 IDE controller code.  I began with
the 2.6.18 version of the it8172.c file, and have moved it forward so
that it works with the latest version of the kernel.  I have run this
driver on a PMC-Sierra Xiao Hu board with the 2.6.28 kernel, and
I have had no problems with it in my configuration.  The attached patch
applies cleanly against 2.6.28.

Signed-off-by: Shane McDonald <mcdonald.shane@gmail.com>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: alan@lxorguk.ukuu.org.uk
[bart: s/HWIF(drive)/drive->hwif/]
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:21:01 +01:00
Bartlomiej Zolnierkiewicz 7ee98034d6 piix: sync ich_laptop[] with ata_piix.c
Allows UDMA > 33 on ACER TM290 and ACER Aspire 1694WLMi.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:21:01 +01:00
Bartlomiej Zolnierkiewicz 02c84bde23 ide: update warm-plug HOWTO
Reported-by: Bruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:21:00 +01:00
Bartlomiej Zolnierkiewicz e630fcbe93 ide: fix ide_port_scan() to do ACPI setup after initializing request queues
This makes ide_port_scan()'s behavior match ide_host_register()'s
one and fixes OOPS in elv_may_queue() during port re-scan.

Reported-and-tested-by: Bruno Prémont <bonbons@linux-vserver.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:21:00 +01:00
Bartlomiej Zolnierkiewicz c38714ed44 ide: remove now redundant ->cur_dev checks
* ->cur_dev should now be always valid if ->handler is set so
  remove redundant checks from ide_intr() and ide_timer_expiry().

* Apply CodingStyle fixups in ide_timer_expiry() while at it.

There should be no functional changes caused by this patch.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:59 +01:00
Bartlomiej Zolnierkiewicz 94c96445f3 ide: remove unused ide_hwif_t.sg_mapped field
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:59 +01:00
Bartlomiej Zolnierkiewicz 906ef986a7 ide: struct ide_atapi_pc - remove unused fields and update documentation
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:59 +01:00
Bartlomiej Zolnierkiewicz b1b1cd9a23 ide: remove superfluous hwif variable assignment from ide_timer_expiry()
There should be no functional changes caused by this patch.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:58 +01:00
Bartlomiej Zolnierkiewicz 8c6de94cfa ide: use ide_pci_is_in_compatibility_mode() helper in setup-pci.c
There should be no functional changes caused by this patch.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:58 +01:00
Bartlomiej Zolnierkiewicz 9600dcf134 ide: make "paranoia" ->handler check in ide_intr() more strict
If ->handler is set while it shouldn't be it indicates deep problems
so BUG_ON()-ning and preventing further damage is much more appropriate
than merely printing an error message.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:58 +01:00
Borislav Petkov d6251d4488 ide-cd: convert to ide-atapi facilities
... and remove no longer needed cdrom_start_packet_command and
cdrom_transfer_packet_command.

Tested lightly with ide-cd and ide-floppy.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:58 +01:00
Borislav Petkov 1e91477aa3 ide-cd: start DMA before sending the actual packet command
as it is done for all other IDE ATAPI devices.

There should be no functionality change resulting from this patch.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:57 +01:00
Borislav Petkov 7a38f3cf01 ide-cd: wait for DRQ to get set per default
... instead of assuming it is set for accelerated DRQ type devices.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:57 +01:00
Mario Schwalbe 744a82b004 ide: Fix drive's DWORD-IO handling
According the documentation, id[ATA_ID_DWORD_IO] is non-zero if
the drive supports dword IO, while the code disables support by
setting IDE_DFLAG_NO_IO_32BIT. In addition, this word has been
reused by the ATA8 specification. This patch fixes both cases.

Signed-off-by: Mario Schwalbe <schwalbe@inf.tu-dresden.de>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
[bart: remove id[ATA_ID_DWORD_IO] check altogether per Sergei's suggestion]
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:57 +01:00
Bartlomiej Zolnierkiewicz 2bd24a1cfc ide: add port and host iterators
Add ide_port_for_each_dev() / ide_host_for_each_port() iterators
and update IDE code to use them.

While at it:
- s/unit/i/ variable in ide_port_wait_ready(), ide_probe_port(),
  ide_port_tune_devices(), ide_port_init_devices_data(), do_reset1(),
  ide_acpi_set_state() and scc_dma_end()
- s/d/i/ variable in ide_proc_port_register_devices()

There should be no functional changes caused by this patch.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:56 +01:00
Bartlomiej Zolnierkiewicz 5e7f3a4669 ide: dynamic allocation of device structures
Allocate device structures dynamically instead of having them embedded
in ide_hwif_t:

* Remove needless zeroing of port structure from ide_init_port_data().

* Add ide_hwif_t.devices[MAX_DRIVES] (table of pointers to the devices).

* Add ide_port_{alloc,free}_devices() helpers and use them respectively
  in ide_{host,free}_alloc().

* Convert all users of ->drives[] to use ->devices[] instead.

While at it:

* Use drive->dn for the slave device check in scc_pata.c.

As a nice side-effect this patch cuts ~1kB (x86-32) from the resulting
code size:

   text    data     bss     dec     hex filename
  53963    1244     237   55444    d894 drivers/ide/ide-core.o.before
  52981    1244     237   54462    d4be drivers/ide/ide-core.o.after

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:56 +01:00
Bartlomiej Zolnierkiewicz a32296f938 ide: NUMA aware allocation of host and port structures
kzalloc() -> kzalloc_node() in ide_host_alloc().

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:56 +01:00
Bartlomiej Zolnierkiewicz 07af5a5b02 it821x: use ide_get_pair_dev() helper
Because presence of the peer device was not checked in
it821x_set_pio_mode() PIO0 mode was used for taskfile PIO
in single device configurations.

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:56 +01:00
Bartlomiej Zolnierkiewicz 5d44a1502f cmd64x: use ide_get_pair_dev() helper
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>
2009-01-06 17:20:55 +01:00
Bartlomiej Zolnierkiewicz 2b78ff5235 cmd640: use ide_get_pair_dev() helper
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>
2009-01-06 17:20:55 +01:00
Bartlomiej Zolnierkiewicz bca4ff16e9 amd74xx: use ide_get_pair_dev() helper
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>
2009-01-06 17:20:54 +01:00
Bartlomiej Zolnierkiewicz 627e05daa1 ide: remove ->error method from struct ide_driver
* Remove (now superfluous) ->error method from struct ide_driver.

* Unexport __ide_error() and make it static.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:54 +01:00
Bartlomiej Zolnierkiewicz 585e9715c2 ide: unexport ide_wait_not_busy()
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:53 +01:00
Bartlomiej Zolnierkiewicz 7f3c868ba7 ide: remove ide_driver_t typedef
While at it:
- s/struct ide_driver_s/struct ide_driver/
- use to_ide_driver() macro in ide-proc.c

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:53 +01:00
Bartlomiej Zolnierkiewicz 9892ec5497 ide: remove 'byte' typedef
Just use u8 instead, also s/__u8/u8/ in ide-cd.h while at it.

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:53 +01:00
Bartlomiej Zolnierkiewicz c0ae502347 ide: remove ide_pci_enablebit_t typedef
Remove needless parens while at it.

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:52 +01:00
Bartlomiej Zolnierkiewicz 54cc1428cf ide: remove local_irq_set() macro
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:52 +01:00
Bartlomiej Zolnierkiewicz 898ec223fe ide: remove HWIF() macro
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:52 +01:00
Bartlomiej Zolnierkiewicz b40d1b88f1 ide: move ide_init_port_data() and friends to ide-probe.c
* Move IDE_DEFAULT_MAX_FAILURES to <linux/ide.h>.

* Move ide_cfg_mtx, ide_hwif_to_major[], ide_port_init_devices_data(),
  ide_init_port_data(), ide_init_port_hw() and ide_unregister() to
  ide-probe.c from ide.c.

* Make ide_unregister(), ide_init_port_data(), ide_init_port_hw()
  and ide_cfg_mtx static.

While at it:

* Remove stale ide_init_port_data() documentation and ide_lock extern.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:51 +01:00
Bartlomiej Zolnierkiewicz ff670e632e ide: update ide_unregister() documentation
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:51 +01:00
Bartlomiej Zolnierkiewicz b65fac32cf ide: merge ide_hwgroup_t with ide_hwif_t (v2)
* Merge ide_hwgroup_t with ide_hwif_t.

* Cleanup init_irq() accordingly, then remove no longer needed
  ide_remove_port_from_hwgroup() and ide_ports[].

* Remove now unused HWGROUP() macro.

While at it:

* ide_dump_ata_error() fixups

v2:
* Fix ->quirk_list check in do_ide_request()
  (s/hwif->cur_dev/prev_port->cur_dev).

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:50 +01:00
Bartlomiej Zolnierkiewicz 5b31f855f1 ide: use lock bitops for ports serialization (v2)
* Add ->host_busy field to struct ide_host and use it's first bit
  together with lock bitops to provide new ports serialization method.

* Convert core IDE code to use new ide_[un]lock_host() helpers.

  This removes the need for taking hwgroup->lock if host is already
  busy on serialized hosts and makes it possible to merge ide_hwgroup_t
  into ide_hwif_t (done in the later patch).

* Remove no longer needed ide_hwgroup_t.busy and ide_[un]lock_hwgroup().

* Update do_ide_request() documentation.

v2:
* ide_release_lock() should be called inside IDE_HFLAG_SERIALIZE check.

* Add ide_hwif_t.busy flag and ide_[un]lock_port() for serializing
  devices on a port.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:49 +01:00
Bartlomiej Zolnierkiewicz efe0397eef ide: remove hwgroup->hwif and {drive,hwif}->next
* Add 'int port_count' field to ide_hwgroup_t to keep the track
  of the number of ports in the hwgroup.  Then update init_irq()
  and ide_remove_port_from_hwgroup() to use it.

* Remove no longer needed hwgroup->hwif, {drive,hwif}->next,
  ide_add_drive_to_hwgroup() and ide_remove_drive_from_hwgroup()
  (hwgroup->drive now only denotes the currently active device
   in the hwgroup).

* Update locking documentation in <linux/ide.h>.

While at it:

* Rename ->drive field in ide_hwgroup_t to ->cur_dev.

* Use __func__ in ide_timer_expiry().

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:49 +01:00
Bartlomiej Zolnierkiewicz ae86afaee6 ide: use per-port IRQ handlers
Use hwif instead of hwgroup as {request,free}_irq()'s cookie,
teach ide_intr() to return early for non-active serialized ports,
modify unexpected_intr() accordingly and then use per-port IRQ
handlers instead of per-hwgroup ones.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:48 +01:00
Bartlomiej Zolnierkiewicz bd53cbcce5 ide: add ->cur_port to struct ide_host and use it for serialized hosts
* Pass 'ide_hwif_t *' instead of 'ide_hwgroup_t *' to unexpected_intr().

* Cache pointer to the port currently being serviced in ->cur_port
  and use it instead of hwif->hwgroup on serialized hosts.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:48 +01:00
Bartlomiej Zolnierkiewicz 42cf2611b2 ide: fix setting nIEN on idle devices
Fix do_ide_request() to operate on previous device / port instead of
the current one.  The original code was wrong since at least Feb 2002
(2.4.0 timeframe).

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:47 +01:00
Bartlomiej Zolnierkiewicz b46f205da6 ide: fix LOCKDEP warning
commit 295f00042a ("ide: don't execute
the next queued command from the hard-IRQ context") overlooked that
ide_do_drive_cmd() (used for REQUEST SENSE command handling) may still
invoke do_ide_request() (->request_fn) in the hard-IRQ context through
blk_start_queueing().  This resulted in a LOCKDEP warning after commit
b599bc7a1199419e122cb2e9ec6b0fa2cfbbc17b ("ide: use per-device request
queue locks (v2)").

Since calling blk_start_queuing() in ide_do_drive_cmd() doesn't make
much sense as the port is already marked as busy (so the execution of
the new command will be deferred anyway) then just remove it fixing
LOCKDEP warning and saving some CPU cycles at the same time.

Reported-and-tested-by: Larry Finger <Larry.Finger@lwfinger.net>
Reported-by: Grissiom <chaos.proton@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-06 17:20:47 +01:00
Linus Torvalds 238c6d5483 Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm
* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm:
  dm snapshot: extend exception store functions
  dm snapshot: split out exception store implementations
  dm snapshot: rename struct exception_store
  dm snapshot: separate out exception store interface
  dm mpath: move trigger_event to system workqueue
  dm: add name and uuid to sysfs
  dm table: rework reference counting
  dm: support barriers on simple devices
  dm request: extend target interface
  dm request: add caches
  dm ioctl: allow dm_copy_name_and_uuid to return only one field
  dm log: ensure log bitmap fits on log device
  dm log: move region_size validation
  dm log: avoid reinitialising io_req on every operation
  dm: consolidate target deregistration error handling
  dm raid1: fix error count
  dm log: fix dm_io_client leak on error paths
  dm snapshot: change yield to msleep
  dm table: drop reference at unbind
2009-01-05 19:20:59 -08:00
Jonathan Brassow a159c1ac5f dm snapshot: extend exception store functions
Supply dm_add_exception as a callback to the read_metadata function.
Add a status function ready for a later patch and name the functions
consistently.

Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-01-06 03:05:19 +00:00
Alasdair G Kergon 4db6bfe02b dm snapshot: split out exception store implementations
Move the existing snapshot exception store implementations out into
separate files.  Later patches will place these behind a new
interface in preparation for alternative implementations.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-01-06 03:05:17 +00:00
Jonathan Brassow 1ae25f9c93 dm snapshot: rename struct exception_store
Rename struct exception_store to dm_exception_store.

Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-01-06 03:05:16 +00:00
Jonathan Brassow aea53d92f7 dm snapshot: separate out exception store interface
Pull structures that bridge the gap between snapshot and
exception store out of dm-snap.h and put them in a new
.h file - dm-exception-store.h.  This file will define the
API for new exception stores.

Ultimately, dm-snap.h is unnecessary, since only dm-snap.c
should be using it.

Signed-off-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-01-06 03:05:15 +00:00
Alasdair G Kergon fe9cf30eb8 dm mpath: move trigger_event to system workqueue
The same workqueue is used both for sending uevents and processing queued I/O.
Deadlock has been reported in RHEL5 when sending a uevent was blocked waiting
for the queued I/O to be processed.  Use scheduled_work() for the asynchronous
uevents instead.

Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-01-06 03:05:13 +00:00
Milan Broz 784aae735d dm: add name and uuid to sysfs
Implement simple read-only sysfs entry for device-mapper block device.

This patch adds a simple sysfs directory named "dm" under block device
properties and implements
	- name attribute (string containing mapped device name)
	- uuid attribute (string containing UUID, or empty string if not set)

The kobject is embedded in mapped_device struct, so no additional
memory allocation is needed for initializing sysfs entry.

During the processing of sysfs attribute we need to lock mapped device
which is done by a new function dm_get_from_kobj, which returns the md
associated with kobject and increases the usage count.

Each 'show attribute' function is responsible for its own locking.

Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-01-06 03:05:12 +00:00
Mikulas Patocka d58168763f dm table: rework reference counting
Rework table reference counting.

The existing code uses a reference counter. When the last reference is
dropped and the counter reaches zero, the table destructor is called.
Table reference counters are acquired/released from upcalls from other
kernel code (dm_any_congested, dm_merge_bvec, dm_unplug_all).
If the reference counter reaches zero in one of the upcalls, the table
destructor is called from almost random kernel code.

This leads to various problems:
* dm_any_congested being called under a spinlock, which calls the
  destructor, which calls some sleeping function.
* the destructor attempting to take a lock that is already taken by the
  same process.
* stale reference from some other kernel code keeps the table
  constructed, which keeps some devices open, even after successful
  return from "dmsetup remove". This can confuse lvm and prevent closing
  of underlying devices or reusing device minor numbers.

The patch changes reference counting so that the table destructor can be
called only at predetermined places.

The table has always exactly one reference from either mapped_device->map
or hash_cell->new_map. After this patch, this reference is not counted
in table->holders.  A pair of dm_create_table/dm_destroy_table functions
is used for table creation/destruction.

Temporary references from the other code increase table->holders. A pair
of dm_table_get/dm_table_put functions is used to manipulate it.

When the table is about to be destroyed, we wait for table->holders to
reach 0. Then, we call the table destructor.  We use active waiting with
msleep(1), because the situation happens rarely (to one user in 5 years)
and removing the device isn't performance-critical task: the user doesn't
care if it takes one tick more or not.

This way, the destructor is called only at specific points
(dm_table_destroy function) and the above problems associated with lazy
destruction can't happen.

Finally remove the temporary protection added to dm_any_congested().

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-01-06 03:05:10 +00:00
Andi Kleen ab4c142488 dm: support barriers on simple devices
Implement barrier support for single device DM devices

This patch implements barrier support in DM for the common case of dm linear
just remapping a single underlying device. In this case we can safely
pass the barrier through because there can be no reordering between
devices.

 NB. Any DM device might cease to support barriers if it gets
     reconfigured so code must continue to allow for a possible
     -EOPNOTSUPP on every barrier bio submitted.  - agk

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-01-06 03:05:09 +00:00
Kiyoshi Ueda 7d76345da6 dm request: extend target interface
This patch adds the following target interfaces for request-based dm.

  map_rq    : for mapping a request

  rq_end_io : for finishing a request

  busy      : for avoiding performance regression from bio-based dm.
              Target can tell dm core not to map requests now, and
              that may help requests in the block layer queue to be
              bigger by I/O merging.
              In bio-based dm, this behavior is done by device
              drivers managing the block layer queue.
              But in request-based dm, dm core has to do that
              since dm core manages the block layer queue.

Signed-off-by: Kiyoshi Ueda <k-ueda@ct.jp.nec.com>
Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2009-01-06 03:05:07 +00:00