linux-stable.git/include/scsi/libsas.h, branch linux-3.2.y

scsi: libsas: align sata_device's rps_resp on a cacheline

2018-03-03T15:50:39+00:00

commit c2e8fbf908afd81ad502b567a6639598f92c9b9d upstream.

The rps_resp buffer in ata_device is a DMA target, but it isn't
explicitly cacheline aligned. Due to this, adjacent fields can be
overwritten with stale data from memory on non-coherent architectures.
As a result, the kernel is sometimes unable to communicate with an SATA
device behind a SAS expander.

Fix this by ensuring that the rps_resp buffer is cacheline aligned.

This issue is similar to that fixed by Commit 84bda12af31f93 ("libata:
align ap->sector_buf") and Commit 4ee34ea3a12396f35b26 ("libata: Align
ata_device's id on a cacheline").

Signed-off-by: Huacai Chen 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Martin K. Petersen 
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings

libsas: remove unused ata_task_resp fields

2018-03-03T15:50:38+00:00

commit 95ac7fd189b7e81a200b4d00b2bb6669b31acf3a upstream.

Commit 1e34c838 "[SCSI] libsas: remove spurious sata control register
read/write" removed the routines to fake the presence of the sata
control registers, now remove the unused data structure fields to kill
any remaining confusion.

Acked-by: Jack Wang 
Signed-off-by: Dan Williams 
Signed-off-by: James Bottomley 
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings

libsas: prevent double completion of scmds from eh

2017-11-11T13:34:50+00:00

commit a3a142524aa4b1539a64a55087bf12ffa4b1f94e upstream.

We invoke task->task_done() to free the task in the eh case, but at this
point we are prepared for scsi_eh_flush_done_q() to finish off the scmd.

Introduce sas_end_task() to capture the final response status from the
lldd and free the task.

Also take the opportunity to kill this warning.
drivers/scsi/libsas/sas_scsi_host.c: In function ‘sas_end_task’:
drivers/scsi/libsas/sas_scsi_host.c:102:3: warning: case value ‘2’ not in enumerated type ‘enum exec_status’ [-Wswitch]

Signed-off-by: Dan Williams 
Signed-off-by: James Bottomley 
Signed-off-by: Ben Hutchings

libsas: fix taskfile corruption in sas_ata_qc_fill_rtf

2012-07-25T03:11:12+00:00

commit 6ef1b512f4e6f936d89aa20be3d97a7ec7c290ac upstream.

fill_result_tf() grabs the taskfile flags from the originating qc which
sas_ata_qc_fill_rtf() promptly overwrites.  The presence of an
ata_taskfile in the sata_device makes it tempting to just copy the full
contents in sas_ata_qc_fill_rtf().  However, libata really only wants
the fis contents and expects the other portions of the taskfile to not
be touched by ->qc_fill_rtf.  To that end store a fis buffer in the
sata_device and use ata_tf_from_fis() like every other ->qc_fill_rtf()
implementation.

Reported-by: Praveen Murali 
Tested-by: Praveen Murali 
Signed-off-by: Dan Williams 
Signed-off-by: James Bottomley 
[bwh: Backported to 3.2: adjust context]
Signed-off-by: Ben Hutchings

[SCSI] libsas: fix port->dev_list locking

2011-10-16T15:54:02+00:00

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 
Signed-off-by: James Bottomley

[SCSI] isci: atapi support

2011-10-02T18:20:03+00:00

Based on original implementation from Jiangbi Liu and Maciej Trela.

ATAPI transfers happen in two-to-three stages.  The two stage atapi
commands are those that include a dma data transfer.  The data transfer
portion of these operations is handled by the hardware packet-dma
acceleration.  The three-stage commands do not have a data transfer and
are handled without hardware assistance in raw frame mode.

stage1: transmit host-to-device fis to notify the device of an incoming
atapi cdb.  Upon reception of the pio-setup-fis repost the task_context
to perform the dma transfer of the cdb+data (go to stage3), or repost
the task_context to transmit the cdb as a raw frame (go to stage 2).

stage2: wait for hardware notification of the cdb transmission and then
go to stage 3.

stage3: wait for the arrival of the terminating device-to-host fis and
terminate the command.

To keep the implementation simple we only support ATAPI packet-dma
protocol (for commands with data) to avoid needing to handle the data
transfer manually (like we do for SATA-PIO).  This may affect
compatibility for a small number of devices (see
ATA_HORKAGE_ATAPI_MOD16_DMA).

If the data-transfer underruns, or encounters an error the
device-to-host fis is expected to arrive in the unsolicited frame queue
to pass to libata for disposition.  However, in the DONE_UNEXP_FIS (data
underrun) case it appears we need to craft a response.  In the
DONE_REG_ERR case we do receive the UF and propagate it to libsas.

Signed-off-by: Maciej Trela 
Signed-off-by: Dan Williams 
Signed-off-by: James Bottomley

[SCSI] libsas: fix try_test_sas_gpio_gp_bit() build error

2011-10-02T17:47:40+00:00

If the user has disabled CONFIG_SCSI_SAS_HOST_SMP then libsas drivers
will not be receiving smp-gpio frames and do not need this lookup code.

Reported-by: Randy Dunlap 
Tested-by: Randy Dunlap 
Signed-off-by: Dan Williams 
Signed-off-by: James Bottomley

[SCSI] libsas: Allow expander T-T attachments

2011-10-02T17:23:11+00:00

Allow expander table-to-table attachments for
expanders that support it.

Signed-off-by: Luben Tuikov 
Signed-off-by: James Bottomley

[SCSI] libsas: sgpio write support

2011-09-22T10:59:09+00:00

Add SFF-8485 v0.7 / SAS-1 smp-write-gpio register support to libsas.
Defer SAS-2 support unless/until it defines an sgpio interface.

Minimum implementation needed to get the lights blinking.
try_test_sas_gpio_gp_bit() provides a common method to parse the
incoming write data (raw bitstream), and the to_sas_gpio_gp_bit() helper
routine can be used as a basis for the set/clear operations for the
'read' implementation.  Host implementations parse as many bits
(ODx.[012]) as are locally supported and report the number of registers
successfully written.  If the submitted data overruns the internal
number of registers available report the write as a success with the
number of bytes remaining reported in ->resid_len.

Example (assuming an active backplane) set the "identify" pattern for
the first 21 devices:

smp_write_gpio --count=2 --data=92,49,24,92,24,92,49,24 -t 4 --index=1 /dev/bsg/sas_hostX

Signed-off-by: Dan Williams 
Signed-off-by: James Bottomley

[SCSI] libsas: export sas_alloc_task()

2011-08-27T14:35:13+00:00

Now that isci has added a 3rd open coded user of this functionality just
share the libsas version.

Acked-by: Jack Wang 
Signed-off-by: Dan Williams 
Signed-off-by: James Bottomley