Commit Graph

75 Commits

Author SHA1 Message Date
Kent Overstreet 458b76ed2f block: Kill bio_segments()/bi_vcnt usage
When we start sharing biovecs, keeping bi_vcnt accurate for splits is
going to be error prone - and unnecessary, if we refactor some code.

So bio_segments() has to go - but most of the existing users just needed
to know if the bio had multiple segments, which is easier - add a
bio_multiple_segments() for them.

(Two of the current uses of bio_segments() are going to go away in a
couple patches, but the current implementation of bio_segments() is
unsafe as soon as we start doing driver conversions for immutable
biovecs - so implement a dumb version for bisectability, it'll go away
in a couple patches)

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Neil Brown <neilb@suse.de>
Cc: Nagalakshmi Nandigama <Nagalakshmi.Nandigama@lsi.com>
Cc: Sreekanth Reddy <Sreekanth.Reddy@lsi.com>
Cc: "James E.J. Bottomley" <JBottomley@parallels.com>
2013-11-23 22:33:51 -08:00
James Bottomley 832e77bc11 Merge branch 'misc' into for-linus
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-05-10 07:53:40 -07:00
James Bottomley aa9f8328fc [SCSI] sas: unify the pointlessly separated enums sas_dev_type and sas_device_type
These enums have been separate since the dawn of SAS, mainly because the
latter is a procotol only enum and the former includes additional state
for libsas.  The dichotomy causes endless confusion about which one you
should use where and leads to pointless warnings like this:

drivers/scsi/mvsas/mv_sas.c: In function 'mvs_update_phyinfo':
drivers/scsi/mvsas/mv_sas.c:1162:34: warning: comparison between 'enum sas_device_type' and 'enum sas_dev_type' [-Wenum-compare]

Fix by eliminating one of them.  The one kept is effectively the sas.h
one, but call it sas_device_type and make sure the enums are all
properly namespaced with the SAS_ prefix.

Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-05-10 07:47:52 -07:00
Linus Torvalds 4de13d7aa8 Merge branch 'for-3.10/core' of git://git.kernel.dk/linux-block
Pull block core updates from Jens Axboe:

 - Major bit is Kents prep work for immutable bio vecs.

 - Stable candidate fix for a scheduling-while-atomic in the queue
   bypass operation.

 - Fix for the hang on exceeded rq->datalen 32-bit unsigned when merging
   discard bios.

 - Tejuns changes to convert the writeback thread pool to the generic
   workqueue mechanism.

 - Runtime PM framework, SCSI patches exists on top of these in James'
   tree.

 - A few random fixes.

* 'for-3.10/core' of git://git.kernel.dk/linux-block: (40 commits)
  relay: move remove_buf_file inside relay_close_buf
  partitions/efi.c: replace useless kzalloc's by kmalloc's
  fs/block_dev.c: fix iov_shorten() criteria in blkdev_aio_read()
  block: fix max discard sectors limit
  blkcg: fix "scheduling while atomic" in blk_queue_bypass_start
  Documentation: cfq-iosched: update documentation help for cfq tunables
  writeback: expose the bdi_wq workqueue
  writeback: replace custom worker pool implementation with unbound workqueue
  writeback: remove unused bdi_pending_list
  aoe: Fix unitialized var usage
  bio-integrity: Add explicit field for owner of bip_buf
  block: Add an explicit bio flag for bios that own their bvec
  block: Add bio_alloc_pages()
  block: Convert some code to bio_for_each_segment_all()
  block: Add bio_for_each_segment_all()
  bounce: Refactor __blk_queue_bounce to not use bi_io_vec
  raid1: use bio_copy_data()
  pktcdvd: Use bio_reset() in disabled code to kill bi_idx usage
  pktcdvd: use bio_copy_data()
  block: Add bio_copy_data()
  ...
2013-05-08 10:13:35 -07:00
Lukasz Dorau d4a2618fa7 [SCSI] libsas: fix handling vacant phy in sas_set_ex_phy()
If a result of the SMP discover function is PHY VACANT,
the content of discover response structure (dr) is not valid.
It sometimes happens that dr->attached_sas_addr can contain
even SAS address of other phy. In such case an invalid phy
is created, what causes NULL pointer dereference during
destruction of expander's phys.

So if a result of SMP function is PHY VACANT, the content of discover
response structure (dr) must not be copied to phy structure.

This patch fixes the following bug:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000030
IP: [<ffffffff811c9002>] sysfs_find_dirent+0x12/0x90
Call Trace:
  [<ffffffff811c95f5>] sysfs_get_dirent+0x35/0x80
  [<ffffffff811cb55e>] sysfs_unmerge_group+0x1e/0xb0
  [<ffffffff813329f4>] dpm_sysfs_remove+0x24/0x90
  [<ffffffff8132b0f4>] device_del+0x44/0x1d0
  [<ffffffffa016fc59>] sas_rphy_delete+0x9/0x20 [scsi_transport_sas]
  [<ffffffffa01a16f6>] sas_destruct_devices+0xe6/0x110 [libsas]
  [<ffffffff8107ac7c>] process_one_work+0x16c/0x350
  [<ffffffff8107d84a>] worker_thread+0x17a/0x410
  [<ffffffff81081b76>] kthread+0x96/0xa0
  [<ffffffff81464944>] kernel_thread_helper+0x4/0x10

Signed-off-by: Lukasz Dorau <lukasz.dorau@intel.com>
Signed-off-by: Pawel Baldysiak <pawel.baldysiak@intel.com>
Reviewed-by: Maciej Patelczyk <maciej.patelczyk@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-04-06 11:36:54 +01:00
John Gong 95c9f4d4da [SCSI] libsas: use right function to alloc smp response
In fact the disc_resp buffer will be overwrite by smp response, so we never
found this typo, correct it by using the right one.

Signed-off-by: John Gong <john_gong@usish.com>
Signed-off-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2013-04-06 11:07:21 +01:00
Kent Overstreet 2f477877f8 block: Remove some unnecessary bi_vcnt usage
More prep work for immutable bvecs/effecient bio splitting - usage of
bi_vcnt has to be auditing, so getting rid of all the unnecessary usage
makes that easier.

Plus, bio_segments() is really what this code wanted, as it respects the
current value of bi_idx.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: Eric Moore <Eric.Moore@lsi.com>
CC: "James E.J. Bottomley" <JBottomley@parallels.com>
CC: linux-scsi@vger.kernel.org
2013-03-23 14:15:31 -07:00
Masanari Iida 02582e9bcc treewide: fix typo of "suport" in various comments and Kconfig
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-11-19 14:16:09 +01:00
Dan Williams f0bf750c2d [SCSI] libsas: trim sas_task of slow path infrastructure
The timer and the completion are only used for slow path tasks (smp, and
lldd tmfs), yet we incur the allocation space and cpu setup time for
every fast path task.

Cc: Xiangliang Yu <yuxiangl@marvell.com>
Acked-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:54 +01:00
Dan Williams b17caa174a [SCSI] libsas: fix sas_discover_devices return code handling
commit 198439e4 [SCSI] libsas: do not set res = 0 in sas_ex_discover_dev()
commit 19252de6 [SCSI] libsas: fix wide port hotplug issues

The above commits seem to have confused the return value of
sas_ex_discover_dev which is non-zero on failure and
sas_ex_join_wide_port which just indicates short circuiting discovery on
already established ports.  The result is random discovery failures
depending on configuration.

Calls to sas_ex_join_wide_port are the source of the trouble as its
return value is errantly assigned to 'res'.  Convert it to bool and stop
returning its result up the stack.

Cc: <stable@vger.kernel.org>
Tested-by: Dan Melnic <dan.melnic@amd.com>
Reported-by: Dan Melnic <dan.melnic@amd.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:53 +01:00
Dan Williams 26f2f199ff [SCSI] libsas: continue revalidation
Continue running revalidation until no more broadcast devices are
discovered.  Fixes cases where re-discovery completes too early in a
domain with multiple expanders with pending re-discovery events.
Servicing BCNs can get backed up behind error recovery.

Cc: <stable@vger.kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:52 +01:00
Jeff Skirvin b2311a2875 [SCSI] libsas: sas_rediscover_dev did not look at the SMP exec status.
The discovery function "sas_rediscover_dev" had two bugs: 1) it did
not pay attention to the return status from the SMP task execution;
2) the stack variable used for the returned SAS address was compared
against 0 without being initialized.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-07-20 08:58:52 +01:00
Dan Williams 7d1d865181 [SCSI] libsas: fix false positive 'device attached' conditions
Normalize phy->attached_sas_addr to return a zero-address in the case
when device-type == NO_DEVICE or the linkrate is invalid to handle
expanders that put non-zero sas addresses in the discovery response:

 sas: ex 5001b4da000f903f phy02:U:0 attached: 0100000000000000 (no device)
 sas: ex 5001b4da000f903f phy01:U:0 attached: 0100000000000000 (no device)
 sas: ex 5001b4da000f903f phy03:U:0 attached: 0100000000000000 (no device)
 sas: ex 5001b4da000f903f phy00:U:0 attached: 0100000000000000 (no device)

Reported-by: Andrzej Jakowski <andrzej.jakowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-04-23 12:14:09 +01:00
Dan Williams b202445925 [SCSI] libsas, libata: fix start of life for a sas ata_port
This changes the ordering of initialization and probing events from:
  1/ allocate rphy in PORTE_BYTES_DMAED, DISCE_REVALIDATE_DOMAIN
  2/ allocate ata_port and schedule port probe in DISCE_PROBE
...to:
  1/ allocate ata_port in PORTE_BYTES_DMAED, DISCE_REVALIDATE_DOMAIN
  2/ allocate rphy in PORTE_BYTES_DMAED, DISCE_REVALIDATE_DOMAIN
  3/ schedule port probe in DISCE_PROBE

This ordering prevents PHYE_SIGNAL_LOSS_EVENTS from sneaking in to
destrory ata devices before they have been fully initialized:

  BUG: unable to handle kernel paging request at 0000000000003b10
  IP: [<ffffffffa0053d7e>] sas_ata_end_eh+0x12/0x5e [libsas]
  ...
  [<ffffffffa004d1af>] sas_unregister_common_dev+0x78/0xc9 [libsas]
  [<ffffffffa004d4d4>] sas_unregister_dev+0x4f/0xad [libsas]
  [<ffffffffa004d5b1>] sas_unregister_domain_devices+0x7f/0xbf [libsas]
  [<ffffffffa004c487>] sas_deform_port+0x61/0x1b8 [libsas]
  [<ffffffffa004bed0>] sas_phye_loss_of_signal+0x29/0x2b [libsas]

...and kills the awkward "sata domain_device briefly existing in the
domain without an ata_port" state.

Reported-by: Michal Kosciowski <michal.kosciowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-04-23 12:11:47 +01:00
Dan Williams 0f3fce5cc7 [SCSI] libsas: fix ata_eh clobbering ex_phys via smp_ata_check_ready
The check_ready implementation in the expander-attached ata device case
polls on sas_ex_phy_discover().  The effect is that the ex_phy fields
(critically ->attached_sas_addr) can change.  When ata_eh ends and
libsas comes along to revalidate the domain
sas_unregister_devs_sas_addr() can fail to lookup devices to remove, or
fail to re-add an ata device that ata_eh marked as disabled.  So change
the code to skip the sas_address and change count updates when ata_eh is
active.

Cc: Jack Wang <jack_wang@usish.com>
Tested-by: Maciej Patelczyk <maciej.patelczyk@intel.com>
Tested-by: Bartek Nowakowski <bartek.nowakowski@intel.com>
Tested-by: Jacek Danecki <jacek.danecki@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-04-23 12:10:34 +01:00
Dan Williams 9487669fc2 [SCSI] libsas: unify domain_device sas_rphy lifetimes
Since the domain_device can out live the scsi_target we need the rphy to
follow suit otherwise we run into issues like:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000050
  IP: [<ffffffffa011561b>] sas_ata_printk+0x43/0x6f [libsas]
  PGD 0
  Oops: 0000 [#1] SMP
  CPU 1
  Modules linked in: ses enclosure isci libsas scsi_transport_sas fuse sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf microcode pcspkr igb joydev iTCO_wdt ioatdma iTCO_vendor_support i2c_i801 i2c_core dca wmi hed ipv6 pata_acpi ata_generic [last unloaded: scsi_wait_scan]

  Pid: 129, comm: kworker/u:3 Not tainted 3.3.0-rc5-isci+ #1 Intel Corporation SandyBridge Platform/To be filled by O.E.M.
  RIP: 0010:[<ffffffffa011561b>] [<ffffffffa011561b>] sas_ata_printk+0x43/0x6f [libsas]
  RSP: 0018:ffff88042232dd70 EFLAGS: 00010282
  RAX: 0000000000000000 RBX: ffff8804283165b8 RCX: ffff88042232dda0
  RDX: ffff88042232dd78 RSI: ffff8804283165b8 RDI: ffffffffa01188d7
  RBP: ffff88042232ddd0 R08: ffff880388454000 R09: ffff8803edfde1f8
  R10: ffff8803edfde1f8 R11: ffff8803edfde1f8 R12: ffff880428316750
  R13: ffff880388454000 R14: ffff8803f88b31d0 R15: ffff8803f8b21d50
  FS: 0000000000000000(0000) GS:ffff88042ee20000(0000) knlGS:0000000000000000
  CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
  CR2: 0000000000000050 CR3: 0000000001a05000 CR4: 00000000000406e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
  Process kworker/u:3 (pid: 129, threadinfo ffff88042232c000, task ffff88042230c920)
  Stack:
  0000000000000000 ffff880400000018 ffff88042232dde0 ffff88042232dda0
  ffffffffa01188c4 ffff88042ee93af0 ffff88042232ddb0 ffffffff8100e047
  ffff88042232de10 ffff880420e5a2c8 ffff8803f8b21d50 ffff8803edfde1f8
  Call Trace:
  [<ffffffff8100e047>] ? load_TLS+0xb/0xf
  [<ffffffffa01156ad>] async_sas_ata_eh+0x66/0x95 [libsas]
  [<ffffffff810655e1>] async_run_entry_fn+0x9e/0x131

Reported-by: Tom Jackson <thomas.p.jackson@intel.com>
Tested-by: Tom Jackson <thomas.p.jackson@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-04-23 12:08:56 +01:00
Thomas Jackson 1699490db3 [SCSI] libsas: fix sas_find_bcast_phy() in the presence of 'vacant' phys
If an expander reports 'PHY VACANT' for a phy index prior to the one
that generated a BCN libsas fails rediscovery.  Since a vacant phy is
defined as a valid phy index that will never have an attached device
just continue the search.

Cc: <stable@vger.kernel.org>
Signed-off-by: Thomas Jackson <thomas.p.jackson@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-04-23 12:06:16 +01:00
Dan Williams 77c309f3cd [SCSI] libsas: fixup target_port_protocols for expanders that don't report sata
If discovery returns 0 for target_port_protocols but shows an attached
sata device, just report SAS_PROTOCOL_SATA in the identify data so
userspace can reliably search for sata devices in the domain.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29 15:41:51 -06:00
Dan Williams 92625f9bff [SCSI] libsas: restore scan order
ata devices are always scanned after ssp.  Prior to the ata error
handling reworks libsas would tend to scan devices in ascending expander
phy order.  Restore this ordering by deferring ssp discovery to a
DISCE_PROBE event, and keep the probe order consistent with the
discovery order, not the placement of sata devices.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29 15:34:19 -06:00
Dan Williams c666aae691 [SCSI] libsas: delete device on sas address changed
If the phy is attached to a new sas address unregister the first address
before processing the new attachment.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29 15:33:39 -06:00
Dan Williams 354cf82980 [SCSI] libsas: let libata recover links that fail to transmit initial sig-fis
libsas fails to discover all sata devices in the domain.  If a device fails
negotiation and does not transmit a signature fis the link needs recovery.
libata already understands how to manage slow to come up links, so treat these
conditions as ata device attach events for the purposes of creating an
ata_port.  This allows libata to manage retrying link bring up.

Rediscovery is modified to be careful about checking changes in dev_type.  It
looks like libsas leaks old devices if the sas address changes, but that's a
fix for another patch.

Acked-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29 15:33:02 -06:00
Dan Williams d214d81e88 [SCSI] libsas: improve debug statements
It's difficult to determine which domain_device is triggering error recovery,
so convert messages like:

  sas: ex 5001b4da000e703f phy08:T attached: 5001b4da000e7028
  sas: ex 5001b4da000e703f phy09:T attached: 5001b4da000e7029
  ...
  ata7: sas eh calling libata port error handler
  ata8: sas eh calling libata port error handler

...into:

  sas: ex 5001517e85cfefff phy05:T:9 attached: 5001517e85cfefe5 (stp)
  sas: ex 5001517e3b0af0bf phy11:T:8 attached: 5001517e3b0af0ab (stp)
  ...
  sas: ata7: end_device-21:1: dev error handler
  sas: ata8: end_device-20:0:5: dev error handler

which shows attached link rate, device type, and associates a
domain_device with its ata_port id to correlate messages emitted from
libata-eh.

As Doug notes, we can also take the opportunity to clarify expander phy
routing capabilities.

[dgilbert@interlog.com: clarify table2table with 'U']
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29 15:28:24 -06:00
Dan Williams f41a0c441c [SCSI] libsas: fix sas_find_local_phy(), take phy references
In the direct-attached case this routine returns the phy on which this
device was first discovered.  Which is broken if we want to support
wide-targets, as this phy reference can become stale even though the
port is still active.

In the expander-attached case this routine tries to lookup the phy by
scanning the attached sas addresses of the parent expander, and BUG_ONs
if it can't find it.  However since eh and the libsas workqueue run
independently we can still be attempting device recovery via eh after
libsas has recorded the device as detached.  This is even easier to hit
now that eh is blocked while device domain rediscovery takes place, and
that libata is fed more timed out commands increasing the chances that
it will try to recover the ata device.

Arrange for dev->phy to always point to a last known good phy, it may be
stale after the port is torn down, but it will catch up for wide port
reconfigurations, and never be NULL.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29 13:01:06 -06:00
Dan Williams 3a9c5560f6 [SCSI] libsas: check for 'gone' expanders in smp_execute_task()
No sense in issuing or retrying commands to an expander that has been
removed.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29 12:55:12 -06:00
Dan Williams 0508c2f3b7 [SCSI] libsas: don't mark expanders as gone when a child device is removed
Commit 56dd2c06 "[SCSI] libsas: Don't issue commands to devices that
have been hot-removed" marked the parent device of an end-device as gone
when all the phys to the end device have been deleted.

The expander device is still present until its parent is removed.  This
is a benign change until the smp_execute_task() path is taught to check
->gone.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29 12:51:48 -06:00
Dan Williams 36a3994739 [SCSI] libsas: poll for ata device readiness after reset
Use ata_wait_after_reset() to poll for link recovery after a reset.
This combined with sas_ha->eh_mutex prevents expander rediscovery from
probing phys in an intermediate state.  Local discovery does not have a
mechanism to filter link status changes during this timeout, so it
remains the responsibility of lldds to prevent premature port teardown.
Although once all lldd's support ->lldd_ata_check_ready() that could be
used as a gate to local port teardown.

The signature fis is re-transmitted when the link comes back so we
should be revalidating the ata device class, but that is left to a future
patch.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-29 12:49:36 -06:00
Jeff Skirvin 89d3cf6ac3 [SCSI] libsas: add mutex for SMP task execution
SAS does not tag SMP requests, and at least one lldd (isci) does not permit
more than one in-flight request at a time.

[jejb: fix sas_init_dev tab issues while we're at it]
Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 14:22:49 -06:00
Dan Williams 81c757bc69 [SCSI] libsas: execute transport link resets with libata-eh via host workqueue
Link resets leave ata affiliations intact, so arrange for libsas to make
an effort to avoid dropping the device due to a slow-to-recover link.
Towards this end carry out reset in the host workqueue so that it can
check for ata devices and kick the reset request to libata.  Hard
resets, in contrast, bypass libata since they are meant for associating
an ata device with another initiator in the domain (tears down
affiliations).

Need to add a new transport_sas_phy_reset() since the current
sas_phy_reset() is a utility function to libsas lldds.  They are not
prepared for it to loop back into eh.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 14:13:51 -06:00
Dan Williams b52df4174d [SCSI] libsas: use libata-eh-reset for sata rediscovery fis transmit failures
Since sata devices can take several seconds to recover the link on reset
the 0.5 seconds that libsas currently waits may not be enough.  Instead
if we are rediscovering a phy that was previously attached to a sata
device let libata handle any resets to encourage the device to transmit
the initial fis.

Once sas_ata_hard_reset() and lldds learn how to honor 'deadline' libsas
should stop encountering phys in an intermediate state, until then this
will loop until the fis is transmitted or ->attached_sas_addr gets
cleared, but in the more likely initial discovery case we keep existing
behavior.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 14:09:32 -06:00
Dan Williams 87c8331fcf [SCSI] libsas: prevent domain rediscovery competing with ata error handling
libata error handling provides for a timeout for link recovery.  libsas
must not rescan for previously known devices in this interval otherwise
it may remove a device that is simply waiting for its link to recover.
Let libata-eh make the determination of when the link is stable and
prevent libsas (host workqueue) from taking action while this
determination is pending.

Using a mutex (ha->disco_mutex) to flush and disable revalidation while
eh is running requires any discovery action that may block on eh be
moved to its own context outside the lock.  Probing ATA devices
explicitly waits on ata-eh and the cache-flush-io issued during device
removal may also pend awaiting eh completion.  Essentially any rphy
add/remove activity needs to run outside the lock.

This adds two new cleanup states for sas_unregister_domain_devices()
'allocated-but-not-probed', and 'flagged-for-destruction'.  In the
'allocated-but-not-probed' state  dev->rphy points to a rphy that is
known to have not been through a sas_rphy_add() event.  At domain
teardown check if this device is still pending probe and cleanup
accordingly.  Similarly if a device has already been queued for removal
then sas_unregister_domain_devices has nothing to do.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 13:52:34 -06:00
Dan Williams e139942d77 [SCSI] libsas: convert dev->gone to flags
In preparation for adding tracking of another device state "destroy".

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 13:51:23 -06:00
Dan Williams 735f7d2fed [SCSI] libsas: fix domain_device leak
Arrange for the deallocation of a struct domain_device object when it no
longer has:
1/ any children
2/ references by any scsi_targets
3/ references by a lldd

The comment about domain_device lifetime in
Documentation/scsi/libsas.txt is stale as it appears mainline never had
a version of a struct domain_device that was registered as a kobject.
We now manage domain_device reference counts on behalf of external
agents.

Reviewed-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 13:37:47 -06:00
Linus Torvalds ec7ae51753 Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (204 commits)
  [SCSI] qla4xxx: export address/port of connection (fix udev disk names)
  [SCSI] ipr: Fix BUG on adapter dump timeout
  [SCSI] megaraid_sas: Fix instance access in megasas_reset_timer
  [SCSI] hpsa: change confusing message to be more clear
  [SCSI] iscsi class: fix vlan configuration
  [SCSI] qla4xxx: fix data alignment and use nl helpers
  [SCSI] iscsi class: fix link local mispelling
  [SCSI] iscsi class: Replace iscsi_get_next_target_id with IDA
  [SCSI] aacraid: use lower snprintf() limit
  [SCSI] lpfc 8.3.27: Change driver version to 8.3.27
  [SCSI] lpfc 8.3.27: T10 additions for SLI4
  [SCSI] lpfc 8.3.27: Fix queue allocation failure recovery
  [SCSI] lpfc 8.3.27: Change algorithm for getting physical port name
  [SCSI] lpfc 8.3.27: Changed worst case mailbox timeout
  [SCSI] lpfc 8.3.27: Miscellanous logic and interface fixes
  [SCSI] megaraid_sas: Changelog and version update
  [SCSI] megaraid_sas: Add driver workaround for PERC5/1068 kdump kernel panic
  [SCSI] megaraid_sas: Add multiple MSI-X vector/multiple reply queue support
  [SCSI] megaraid_sas: Add support for MegaRAID 9360/9380 12GB/s controllers
  [SCSI] megaraid_sas: Clear FUSION_IN_RESET before enabling interrupts
  ...
2011-10-28 16:44:18 -07:00
Dan Williams 1a34c06401 [SCSI] libsas: fix port->dev_list locking
port->dev_list maintains a list of devices attached to a given sas root port.
It needs to be mutated under a lock as contexts outside of the
single-threaded-libsas-workqueue access the list via sas_find_dev_by_rphy().
Fixup locations where the list was being mutated without a lock.

This is a follow-up to commit 5911e963 "[SCSI] libsas: remove expander
from dev list on error", where Luben noted [1]:

    > 2/ We have unlocked list manipulations in sas_ex_discover_end_dev(),
    > sas_unregister_common_dev(), and sas_ex_discover_end_dev()

    Yes, I can see that and that is very unfortunate.

[1]: http://marc.info/?l=linux-scsi&m=131480962006471&w=2

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-16 10:54:02 -05:00
Mark Salyzyn a73914c35b [SCSI] libsas: fix panic when single phy is disabled on a wide port
When a wide port is being utilized to a target, if one disables only one
of the
phys, we get an OS crash:

BUG: unable to handle kernel NULL pointer dereference at
0000000000000238
IP: [<ffffffff814ca9b1>] mutex_lock+0x21/0x50
PGD 4103f5067 PUD 41dba9067 PMD 0
Oops: 0002 [#1] SMP
last sysfs file: /sys/bus/pci/slots/5/address
CPU 0
Modules linked in: pm8001(U) ses enclosure fuse nfsd exportfs autofs4
ipmi_devintf ipmi_si ipmi_msghandler nfs lockd fscache nfs_acl
auth_rpcgss 8021q fcoe libfcoe garp libfc scsi_transport_fc stp scsi_tgt
llc sunrpc cpufreq_ondemand acpi_cpufreq freq_table ipv6 sr_mod cdrom
dm_mirror dm_region_hash dm_log uinput sg i2c_i801 i2c_core iTCO_wdt
iTCO_vendor_support e1000e mlx4_ib ib_mad ib_core mlx4_en mlx4_core ext3
jbd mbcache sd_mod crc_t10dif usb_storage ata_generic pata_acpi ata_piix
libsas(U) scsi_transport_sas dm_mod [last unloaded: pm8001]

Modules linked in: pm8001(U) ses enclosure fuse nfsd exportfs autofs4
ipmi_devintf ipmi_si ipmi_msghandler nfs lockd fscache nfs_acl
auth_rpcgss 8021q fcoe libfcoe garp libfc scsi_transport_fc stp scsi_tgt
llc sunrpc cpufreq_ondemand acpi_cpufreq freq_table ipv6 sr_mod cdrom
dm_mirror dm_region_hash dm_log uinput sg i2c_i801 i2c_core iTCO_wdt
iTCO_vendor_support e1000e mlx4_ib ib_mad ib_core mlx4_en mlx4_core ext3
jbd mbcache sd_mod crc_t10dif usb_storage ata_generic pata_acpi ata_piix
libsas(U) scsi_transport_sas dm_mod [last unloaded: pm8001]
Pid: 5146, comm: scsi_wq_5 Not tainted
2.6.32-71.29.1.el6.lustre.7.x86_64 #1 Storage Server
RIP: 0010:[<ffffffff814ca9b1>]  [<ffffffff814ca9b1>]
mutex_lock+0x21/0x50
RSP: 0018:ffff8803e4e33d30  EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000238 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff8803e664c800 RDI: 0000000000000238
RBP: ffff8803e4e33d40 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000238 R14: ffff88041acb7200 R15: ffff88041c51ada0
FS:  0000000000000000(0000) GS:ffff880028200000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
CR2: 0000000000000238 CR3: 0000000410143000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process scsi_wq_5 (pid: 5146, threadinfo ffff8803e4e32000, task
ffff8803e4e294a0)
Stack:
 ffff8803e664c800 0000000000000000 ffff8803e4e33d70 ffffffffa001f06e
<0> ffff8803e4e33d60 ffff88041c51ada0 ffff88041acb7200 ffff88041bc0aa00
<0> ffff8803e4e33d90 ffffffffa0032b6c 0000000000000014 ffff88041acb7200
Call Trace:
 [<ffffffffa001f06e>] sas_port_delete_phy+0x2e/0xa0 [scsi_transport_sas]
 [<ffffffffa0032b6c>] sas_unregister_devs_sas_addr+0xac/0xe0 [libsas]
 [<ffffffffa0034914>] sas_ex_revalidate_domain+0x204/0x330 [libsas]
 [<ffffffffa00307f0>] ? sas_revalidate_domain+0x0/0x90 [libsas]
 [<ffffffffa0030855>] sas_revalidate_domain+0x65/0x90 [libsas]
 [<ffffffff8108c7d0>] worker_thread+0x170/0x2a0
 [<ffffffff81091ea0>] ? autoremove_wake_function+0x0/0x40
 [<ffffffff8108c660>] ? worker_thread+0x0/0x2a0
 [<ffffffff81091b36>] kthread+0x96/0xa0
 [<ffffffff810141ca>] child_rip+0xa/0x20
 [<ffffffff81091aa0>] ? kthread+0x0/0xa0
 [<ffffffff810141c0>] ? child_rip+0x0/0x20
Code: ff ff 85 c0 75 ed eb d6 66 90 55 48 89 e5 48 83 ec 10 48 89 1c 24
4c 89 64 24 08 0f 1f 44 00 00 48 89 fb e8 92 f4 ff ff 48 89 df <f0> ff
0f 79 05 e8 25 00 00 00 65 48 8b 04 25 08 cc 00 00 48 2d
RIP  [<ffffffff814ca9b1>] mutex_lock+0x21/0x50
 RSP <ffff8803e4e33d30>
CR2: 0000000000000238

The following patch is admittedly a band-aid, and does not solve the
root cause, but it still is a good candidate for hardening as a pointer
check before reference.

Signed-off-by: Mark Salyzyn <mark_salyzyn@us.xyratex.com>
Tested-by: Jack Wang <jack_wang@usish.com>
Cc: stable@kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-02 13:28:55 -05:00
Jack Wang bb041a0e9c [SCSI] libsas: set sas_address and device type of rphy
Libsas forget to set the sas_address and device type of rphy lead to file
under /sys/class/sas_x show wrong value, fix that.

Signed-off-by: Jack Wang <jack_wang@usish.com>
Tested-by: Crystal Yu <crystal_yu@usish.com>
Cc: stable@kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-02 12:51:06 -05:00
Luben Tuikov ffaac8f45b [SCSI] libsas: Allow expander T-T attachments
Allow expander table-to-table attachments for
expanders that support it.

Signed-off-by: Luben Tuikov <ltuikov@yahoo.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-02 12:23:11 -05:00
Mark Salyzyn 24926dadc4 [SCSI] libsas: fix failure to revalidate domain for anything but the first expander child.
In an enclosure model where there are chaining expanders to a large body
of storage, it was discovered that libsas, responding to a broadcast
event change, would only revalidate the domain of first child expander
in the list.

The issue is that the pointer value to the discovered source device was
used to break out of the loop, rather than the content of the pointer.

This still remains non-compliant as the revalidate domain code is
supposed to loop through all child expanders, and not stop at the first
one it finds that reports a change count. However, the design of this
routine does not allow multiple device discoveries and that would be a
more complicated set of patches reserved for another day. We are fixing
the glaring bug rather than refactoring the code.

Signed-off-by: Mark Salyzyn <msalyzyn@us.xyratex.com>
Cc: stable@kernel.org
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-09-22 11:23:56 +04:00
Luben Tuikov 5911e963d3 [SCSI] libsas: remove expander from dev list on error
If expander discovery fails (sas_discover_expander()), remove the
expander from the port device list (sas_ex_discover_expander()),
before freeing it. Else the list is corrupted and, e.g., when we
attempt to send SMP commands to other devices, the kernel oopses.

Signed-off-by: Luben Tuikov <ltuikov@yahoo.com>
Cc: stable@kernel.org
Reviewed-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-07-27 15:50:58 +04:00
Lucas De Marchi 25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
jack_wang 183ce896d7 [SCSI] libsas: fix loopback topology bug during discovery
In some test envirenment, there is loopback topology test. We should
handle this during discovery.

Signed-off-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-02-28 11:40:34 -06:00
Jack Wang 2bc72c91ea [SCSI] libsas: fix bug for vacant phy
This patch fix bug reported by Chuck. And this new version incorporate comments
from Hannes. Please consider to include it into mainline.

Signed-off-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: Lindar Liu <lindar_liu@usish.com>
Tested-by: Chuck Tuffli <Chuck_Tuffli@pmc-sierra.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-10-11 17:40:00 -05:00
Darrick J. Wong 56dd2c0691 [SCSI] libsas: Don't issue commands to devices that have been hot-removed
sd will get hung up issuing commands to flush write cache if a SAS
device behind the expander is unplugged without warning.  Change libsas
to reject commands to domain devices that have already gone away.

[maciej.trela@intel.com: removed setting ->gone in sas_deform_port() to
 permit sync cache commands at module removal]

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Tested-by: Haipao Fan <haipao.fan@intel.com>
Signed-off-by: Maciej Trela <maciej.trela@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-10-08 16:03:42 -05:00
James Bottomley df64d3caab [SCSI] Unify SAM_ and SAM_STAT_ macros
We have two separate definitions for identical constants with nearly the
same name.  One comes from the generic headers in scsi.h; the other is
an enum in libsas.h ... it's causing confusion about which one is
correct (fortunately they both are).

Fix this by eliminating the libsas.h duplicate

Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-07-28 09:07:49 -05:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
jack wang 198439e4af [SCSI] libsas: do not set res = 0 in sas_ex_discover_dev()
We should not set res to 0 in function sas_ex_discover_dev  in order to let
it discover it further when wide port hotplug in .

Signed-off-by: Tom Peng <tom_peng@usish.com>
Signed-off-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-11-06 13:10:42 -06:00
Tom Peng 19252de681 [SCSI] libsas: fix wide port hotplug issues
Hotplug of phys which form wide ports simply does not work at the moment.  Fix
this by adding checks at the hotplug points to see if the attached sas address
of the phy already exists (in which case it's part of a wide port) and act
accordingly.

Signed-off-by: Tom Peng <tom_peng@usish.com>
Signed-off-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: Lindar Liu <lindar_liu@usish.com>
Signed-off-by: Kevin Ao <aoqingyun@usish.com>
[jejb: tidied up coding, fixed an error case and made TRUE/FALSE lower
 case to fix a ppc64 compile error in linux-next]
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-07-30 09:54:39 -05:00
Tejun Heo 5f49f63178 block: set rq->resid_len to blk_rq_bytes() on issue
In commit c3a4d78c58, while introducing
rq->resid_len, the default value of residue count was changed from
full count to zero.  The conversion was done under the assumption that
when a request fails residue count wasn't defined.  However, Boaz and
James pointed out that this wasn't true and the residue count should
be preserved for failed requests too.

This patchset restores the original behavior by setting rq->resid_len
to blk_rq_bytes(rq) on request start and restoring explicit clearing
in affected drivers.  While at it, take advantage of the fact that
rq->resid_len is set to full count where applicable.

* ide-cd: rq->resid_len cleared on pc success

* mptsas: req->resid_len cleared on success

* sas_expander: rsp/req->resid_len cleared on success

* mpt2sas_transport: req->resid_len cleared on success

* ide-cd, ide-tape, mptsas, sas_host_smp, mpt2sas_transport, ub: take
  advantage of initial full count to simplify code

Boaz Harrosh spotted bug in resid_len initialization.  Fixed as
suggested.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Borislav Petkov <petkovbb@googlemail.com>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-19 11:36:08 +02:00
Tejun Heo b079041030 block: cleanup rq->data_len usages
With recent unification of fields, it's now guaranteed that
rq->data_len always equals blk_rq_bytes().  Convert all non-IDE direct
users to accessors.  IDE will be converted in a separate patch.

Boaz: spotted incorrect data_len/resid_len conversion in osd.

[ Impact: convert direct rq->data_len usages to blk_rq_bytes() ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Markus Lidel <Markus.Lidel@shadowconnect.com>
Cc: Darrick J. Wong <djwong@us.ibm.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:50:55 +02:00
Tejun Heo c3a4d78c58 block: add rq->resid_len
rq->data_len served two purposes - the length of data buffer on issue
and the residual count on completion.  This duality creates some
headaches.

First of all, block layer and low level drivers can't really determine
what rq->data_len contains while a request is executing.  It could be
the total request length or it coulde be anything else one of the
lower layers is using to keep track of residual count.  This
complicates things because blk_rq_bytes() and thus
[__]blk_end_request_all() relies on rq->data_len for PC commands.
Drivers which want to report residual count should first cache the
total request length, update rq->data_len and then complete the
request with the cached data length.

Secondly, it makes requests default to reporting full residual count,
ie. reporting that no data transfer occurred.  The residual count is
an exception not the norm; however, the driver should clear
rq->data_len to zero to signify the normal cases while leaving it
alone means no data transfer occurred at all.  This reverse default
behavior complicates code unnecessarily and renders block PC on some
drivers (ide-tape/floppy) unuseable.

This patch adds rq->resid_len which is used only for residual count.

While at it, remove now unnecessasry blk_rq_bytes() caching in
ide_pc_intr() as rq->data_len is not changed anymore.

Boaz	: spotted missing conversion in osd
Sergei	: spotted too early conversion to blk_rq_bytes() in ide-tape

[ Impact: cleanup residual count handling, report 0 resid by default ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Mike Miller <mike.miller@hp.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Doug Gilbert <dgilbert@interlog.com>
Cc: Mike Miller <mike.miller@hp.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Darrick J. Wong <djwong@us.ibm.com>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-05-11 09:50:53 +02:00