linux-toradex.git/drivers/target/target_core_iblock.c, branch v3.4.2

target: increase iblock task sizes

2012-02-25T22:37:46+00:00

There is no real limit for task sizes in the iblock driver given that we
can chain bios.  Increase the maximum size to UINT_MAX, and change the
code to submit bios in a smaller batch size to avoid deadlocks when
having more bios in flight than the pool supports.  Also increase the
pool size to always allow multiple tasks to be in flight.

I also had to change the task refcounting to include one reference for
the submission task, which is a standard practice in this kind of code
in Linux (e.g. XFS I/O submission).  This was wrong before, but couldn't
be hit easily.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Nicholas Bellinger

target: remove the unused struct iblock_hba

2012-02-25T22:37:46+00:00

There is no reason to allocate a struct just to store the host number for
a debug printk in the detach path.  I've simply removed the verbose
debugging given that the calling code thinks the number passed in is
something different from a host ID anyway.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Nicholas Bellinger

iblock: fix handling of large requests

2012-02-07T06:48:46+00:00

Requesting to many bvecs upsets bio_alloc_bioset, so limit the number we ask
for to the amount it can handle.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Nicholas Bellinger

target: Fix iblock se_dev_attrib.unmap_granularity

2012-02-07T06:48:20+00:00

The block layer keeps q->limits.discard_granularity in bytes, but iblock
(and the SCSI Block Limits VPD page) keep unmap_granularity in blocks.
Report the correct value when exporting block devices by dividing to
convert bytes to blocks.

Signed-off-by: Roland Dreier 
Signed-off-by: Nicholas Bellinger

target: don't allocate bio headroom in iblock

2012-01-18T08:28:02+00:00

We never embedd the bio into a structure, so there is no need to allocate
64 bytes of headroom per bio.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Nicholas Bellinger

target: remove useless casts

2011-12-14T11:28:07+00:00

A reader should spend an extra moment whenever noticing a cast,
because either something special is going on that deserves extra
attention or, as is all too often the case, the code is wrong.

These casts, afaics, have all been useless.  They cast a foo* to a
foo*, cast a void* to the assigned type, cast a foo* to void*, before
assigning it to a void* variable, etc.

In a few cases I also removed an additional &...[0], which is equally
useless.

Lastly I added three FIXMEs where, to the best of my judgement, the
code appears to have a bug.  It would be good if someone could check
these.

Signed-off-by: Joern Engel 
Signed-off-by: Nicholas Bellinger

target: use \n as a separator for configuration

2011-12-14T11:27:23+00:00

The command
| echo rd_pages=32768 > ramdisk/control

Does not work because it writes "rd_pages=32768\n" and the parser which
matches for "rd_pages=%d" does not recognize it due to the \n. One way
of fixing this would be using "echo -n" instead.
This patch adds \n to the list of separators so we don't have to use the
-n argument which I find is more convinient.

Signed-off-by: Sebastian Andrzej Siewior 
Signed-off-by: Nicholas Bellinger

target: header reshuffle, part2

2011-12-14T11:26:05+00:00

This reorganized the headers under include/target into:

 - target_core_base.h stays as is with all target-wide data stuctures and defines
 - target_core_backend.h contains the whole interface to I/O backends
 - target_core_fabric.h contains the whole interface to fabric modules

Except for those only the various configfs macro headers stay around.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Nicholas Bellinger

target: remove the t_tasks_fua se_cmd field

2011-12-06T06:00:52+00:00

And use a SCF_FUA flag instead.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Nicholas Bellinger

target: Address legacy PYX_TRANSPORT_* return code breakage

2011-12-06T06:00:49+00:00

This patch removes legacy usage of PYX_TRANSPORT_* return codes in a number
of locations and addresses cases where transport_generic_request_failure()
was returning the incorrect sense upon CHECK_CONDITION status after the
v3.1 converson to use errno return codes.

This includes the conversion of transport_generic_request_failure() to
process cmd->scsi_sense_reason and handle extra TCM_RESERVATION_CONFLICT
before calling transport_send_check_condition_and_sense() to queue up
response status.  It also drops PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES legacy
usgae, and returns TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE w/ a response
for these cases.

transport_generic_allocate_tasks(), transport_generic_new_cmd(), backend
SCF_SCSI_DATA_SG_IO_CDB ->do_task(), and emulated ->execute_task() have
all been updated to set se_cmd->scsi_sense_reason and return errno codes
universally upon failure.  This includes cmd->scsi_sense_reason assignment
in target_core_alua.c, target_core_pr.c and target_core_cdb.c emulation code.

Finally it updates fabric modules to remove the legacy usage, and for
TFO->new_cmd_map() callers forwards return values outside of fabric code.
iscsi-target has also been updated to remove a handful of special cases
related to the cleanup and signaling QUEUE_FULL handling w/ ft_write_pending()

(v2: Drop extra SCF_SCSI_CDB_EXCEPTION check during failure from
     transport_generic_new_cmd, and re-add missing task->task_error_status
     assignment in transport_complete_task)

Cc: Christoph Hellwig 
Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger