Commit Graph

44 Commits

Author SHA1 Message Date
Christoph Hellwig af8772926f target: replace the processing thread with a TMR work queue
The last functionality of the target processing thread is offloading possibly
long running task management requests from the submitter context.  To keep
TMR semantics the same we need a single threaded ordered queue, which can
be provided by a per-device workqueue with the right flags.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-07-16 17:35:21 -07:00
Christoph Hellwig 5f41a31d0a target: remove the execute list
Since "target: Drop se_device TCQ queue_depth usage from I/O path" we always
submit all commands (or back then, tasks) from __transport_execute_tasks.

That means the the execute list has lots its purpose, as we can simply
submit the commands that are restarted in transport_complete_task_attr
directly while we walk the list.  In fact doing so also solves a race
in the way it currently walks to delayed_cmd_list as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-07-16 17:29:11 -07:00
Christoph Hellwig d43d6aea84 target: remove the t_task_cdbs_ex_left field in struct se_cmd
Now that tasks are gone we are guaranteed to only get a single completion
per command, and thus don't need this counter.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-05-06 15:11:27 -07:00
Christoph Hellwig 226b6faf2e target: remove the t_task_cdbs_left field in struct se_cmd
Now that tasks are gone we are guaranteed to only get a single completion
per command, and thus don't need this counter.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-05-06 15:11:27 -07:00
Christoph Hellwig 5787cacd0b target: remove struct se_task
We can use struct se_cmd for everything it did.  Make sure to pass the S/G
list and data direction to the execution function to ease adding back BIDI
support later on.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-05-06 15:11:26 -07:00
Christoph Hellwig cf572a9627 target: move the state and execute lists to the command
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-05-06 15:11:26 -07:00
Christoph Hellwig 785fdf70b2 target: simplify command to task linkage
Now that we only have a single task per command we can use a direct pointer
to it instead of list.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-05-06 15:11:25 -07:00
Nicholas Bellinger 3d28934aaa target: Add TMR_ABORT_TASK task management support
This patch adds initial support for TMR_ABORT_TASK ops for se_cmd
descriptors using se_sess->sess_cmd_list and se_cmd->cmd_kref counting.

It will perform an explict abort for all outstanding se_cmd ops based
upon tmr->ref_task_tag that have not been set CMD_T_COMPLETE.
It will cancel se_cmd->work and wait for backing I/O to complete before
attempting to send SAM_STAT_TASK_ABORTED and perform
target_put_sess_cmd() to release the referenced descriptor.

It also adds a CMD_T_ABORTED check into transport_complete_task() to
catch the completion from backend I/O that has been aborted, and
updates transport_wait_for_tasks() to allow CMD_T_ABORTED usage with
core_tmr_abort_task() context.

Reported-by: Roland Dreier <roland@purestorage.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 14:37:49 -08:00
Andy Grover c8e31f26fe target: Add SCF_SCSI_TMR_CDB usage and drop se_tmr_req_cache
Change the test for if a cmd is a tmr request to checking if
SCF_SCSI_TMR_CDB (a new flag) is set in cmd->se_cmd_flags.

Also remove se_tmr_req_cache usage in favor of kzalloc usage,
and make core_tmr_alloc_req() return int + setup se_cmd->se_tmr_req
directly and fix up various fabric module usages

Cc: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 14:37:47 -08:00
Christoph Hellwig 7d680f3b74 target: replace various cmd flags with a transport state
Replace various atomic_ts used as flags in struct se_cmd with a single
transport_state bitmap that requires t_state_lock to be held for modifications.

In the target core that assumption generally is true, but some recently added
code in the SRP target had to grow new lock calls.  I can't say I like the way
how it messes with the command state directly, but let's leave that for later.

(Re-add missing ib_srpt.c changes that nab dropped..)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-02-25 14:37:45 -08:00
Jörn Engel feae85644f target: simplify target_check_cdb_and_preempt
- rename to target_check_cdb_and_preempt
- use non-safe list_for_each_entry
- move common check into callee (simplifying callers)

Signed-off-by: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:27:55 +00:00
Jörn Engel c165f69c2c target: Move core_scsi3_check_cdb_abort_and_preempt
And make it static afterwards.

Signed-off-by: Joern Engel <joern@logfs.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:27:34 +00:00
Christoph Hellwig 1880807adb target: make the se_task task_state_active a normal bool
There is no need to make task_state_active an atomic_t given that it is
always set under the execute_task_lock so we can make it a simple bool.
Also rename it to t_state_active to be closer to the list it guards,
and make sure all checks before the list addion/removal actually happen
under execute_task_lock.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:27:02 +00:00
Christoph Hellwig c4795fb20e target: header reshuffle, part2
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 <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:26:05 +00:00
Christoph Hellwig e26d99aed4 target: reshuffle headers
Create a new headers, drivers/target/target_core_internal.h that is supposed
to hold all target_core-internal prototypes.  Move all non-exported includes
from include/target to it, and merge the smaller prototype-only includes
inside drivers/target into it as well.  Mark functions that were found to
not be called outside their implementation file static.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 08:51:12 +00:00
Nicholas Bellinger 03e98c9eb9 target: Address legacy PYX_TRANSPORT_* return code breakage
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 <hch@lst.de>
Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-06 06:00:49 +00:00
Linus Torvalds 32aaeffbd4 Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux
* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
  Revert "tracing: Include module.h in define_trace.h"
  irq: don't put module.h into irq.h for tracking irqgen modules.
  bluetooth: macroize two small inlines to avoid module.h
  ip_vs.h: fix implicit use of module_get/module_put from module.h
  nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
  include: replace linux/module.h with "struct module" wherever possible
  include: convert various register fcns to macros to avoid include chaining
  crypto.h: remove unused crypto_tfm_alg_modname() inline
  uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
  pm_runtime.h: explicitly requires notifier.h
  linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
  miscdevice.h: fix up implicit use of lists and types
  stop_machine.h: fix implicit use of smp.h for smp_processor_id
  of: fix implicit use of errno.h in include/linux/of.h
  of_platform.h: delete needless include <linux/module.h>
  acpi: remove module.h include from platform/aclinux.h
  miscdevice.h: delete unnecessary inclusion of module.h
  device_cgroup.h: delete needless include <linux/module.h>
  net: sch_generic remove redundant use of <linux/module.h>
  net: inet_timewait_sock doesnt need <linux/module.h>
  ...

Fix up trivial conflicts (other header files, and  removal of the ab3550 mfd driver) in
 - drivers/media/dvb/frontends/dibx000_common.c
 - drivers/media/video/{mt9m111.c,ov6650.c}
 - drivers/mfd/ab3550-core.c
 - include/linux/dmaengine.h
2011-11-06 19:44:47 -08:00
Nicholas Bellinger 3151d069e9 target: Remove core TRANSPORT_FREE_CMD_INTR usage
This patch drops TRANSPORT_FREE_CMD_INTR usage from target core, which
includes the removal of transport_generic_free_cmd_intr() symbol,
TRANSPORT_FREE_CMD_INTR usage in transport_processing_thread(), and
special case LUN_RESET handling to skip TRANSPORT_FREE_CMD_INTR processing
in core_tmr_drain_cmd_list().  We now expect that fabric modules will
use an internal workqueue to provide process context when releasing
se_cmd descriptor resources via transport_generic_free_cmd().

Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Madhuranath Iyengar <mni@risingtidesystems.com>
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
2011-11-02 15:58:46 +00:00
Joern Engel b8a11d7399 target: Avoid double list_del for aborted se_tmr_req
After the list_del() in core_tmr_drain_tmr_list(),
core_tmr_release_req() would list_del() the same object again.

Call graph:
        core_tmr_drain_tmr_list
        transport_cmd_finish_abort_tmr
        transport_generic_remove
        transport_free_se_cmd
        core_tmr_release_req

So use list_del_init(), as list_del() of an initialized list_head is
safe and essentially a nop.  In the CONFIG_DEBUG_LIST case, list_del()
actually poisons the list_head, but that is fine as we free the object
directly afterwards.

Signed-off-by: Joern Engel <joern@logfs.org>
Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
2011-11-02 15:56:41 +00:00
Paul Gortmaker c53181af83 drivers/target: Add export.h to files as required.
So that they have access to EXPORT_SYMBOL variants and THIS_MODULE.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:31:58 -04:00
Joern Engel abc1fd4f92 target: Minor cleanups to core_tmr_drain_tmr_list
This patch adds a handful minor cleanups to core_tmr_drain_tmr_list() that
remove an unnecessary NULL check, use list_for_each_entry_safe() instead of
list_entry(), and makes the drain_tmr_list walk use *tmr_p instead of
directly referencing the passed *tmr function parameter.

Signed-off-by: Joern Engel <joern@logfs.org>
Cc: Joern Engel <joern@logfs.org>
Reviewed-by: Roland Dreier <roland@purestorage.com>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-27 01:00:29 +00:00
Joern Engel 6eb40b2af4 target: Fix wrong se_tmr being added to drain_tmr_list
This patch fixes another bug from LUN_RESET re-org fallout in
core_tmr_drain_tmr_list() that was adding the wrong se_tmr_req
into the local drain_tmr_list to be walked + released.

Signed-off-by: Joern Engel <joern@logfs.org>
Cc: Joern Engel <joern@logfs.org>
Reviewed-by: Roland Dreier <roland@purestorage.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-27 01:00:21 +00:00
Joern Engel 80ccbc8e00 target: Fix incorrect se_cmd assignment in core_tmr_drain_tmr_list
This patch fixes a bug in core_tmr_drain_tmr_list() where drain_tmr_list
was using the wrong se_tmr_req for cmd assignment due to a typo during the
LUN_RESET re-org.  This was resulting in general protection faults while
using the leftover bogus *tmr_p pointer from list_for_each_entry_safe().

Signed-off-by: Joern Engel <joern@logfs.org>
Cc: Joern Engel <joern@logfs.org>
Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-27 01:00:11 +00:00
Christoph Hellwig 35e0e75753 target: use a workqueue for I/O completions
Instead of abusing the target processing thread for offloading I/O
completion in the backends to user context add a new workqueue.  This means
completions can be processed as fast as available CPU time allows it,
including in parallel with other completions and more importantly I/O
submission or QUEUE FULL retries.  This should give much better performance
especially on loaded systems.

As a fallout we can merge all the completed states into a single
one.

On the downside this change complicates lun reset handling a bit by
requiring us to cancel a work item only for those states that have it
initialized.  The alternative would be to either always initialize the work
item to a dummy handler, or always use the same handler and do a switch on
the state. The long term solution will be a flag that says that the command
has an initialized work item, but that's only going to be useful once we
have more users.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:52 +00:00
Christoph Hellwig f2da9dbdb5 target: remove TRANSPORT_DEFERRED_CMD state
We never check for this state, and it makes testing for a completed
state much harder given that it overrides the existing state.

Also remove the unused deferred_t_state which is related to it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:49 +00:00
Christoph Hellwig cdbb70bb4c target: factor some duplicate code for stopping a task
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:41 +00:00
Christoph Hellwig 04629b7bde target: Remove unnecessary se_task members
This is a squashed version of the following unnecessary se_task structure
member removal patches:

target: remove the task_execute_queue field in se_task

    Instead of using a separate flag we can simply do list_emptry checks
    on t_execute_list if we make sure to always use list_del_init to remove
    a task from the list.  Also factor some duplicate code into a new
    __transport_remove_task_from_execute_queue helper.

target: remove the read-only task_no field in se_task

    The task_no field never was initialized and only used in debug printks,
    so kill it.

target: remove the task_padded_sg field in se_task

    This field is only check in one place and not actually needed there.

    Rationale:
    - transport_do_task_sg_chain asserts that we have task_sg_chaining
      set early on
    - we only make use of the sg_prev_nents field we calculate based on it
      if there is another sg list that gets chained onto this one, which
      never happens for the last (or only) task.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:08 +00:00
Christoph Hellwig 6c76bf951c target: make more use of the task_flags field in se_task
Replace various atomic_t variables that were mostly under t_state_lock
with new flags in task_flags.  Note that the execution error path
didn't take t_state_lock before, so add it there.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:21:06 +00:00
Nicholas Bellinger 8dc52b5420 target: Merge transport_cmd_finish_abort_tmr into transport_cmd_finish_abort
This patch merges transport_cmd_finish_abort_tmr() logic into a single
transport_cmd_finish_abort() function by adding a cmd->se_tmr_req check
around transport_lun_remove_cmd(), and updates the single caller within
core_tmr_drain_tmr_list().

Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:20:58 +00:00
Roland Dreier dd503a5fcc target: Have core_tmr_alloc_req() take an explicit GFP_xxx flag
Testing in_interrupt() to know when sleeping is allowed is not really
reliable (since eg it won't be true if the caller is holding a spinlock).
Instead have the caller tell core_tmr_alloc_req() what GFP_xxx to use;
every caller except tcm_qla2xxx can use GFP_KERNEL.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-24 03:20:53 +00:00
Nicholas Bellinger b0e062aec5 target: Prevent TRANSPORT_FREE_CMD_INTR processing in core_tmr_drain_cmd_list
This patch contains a bugfix for TMR LUN_RESET related to TRANSPORT_FREE_CMD_INTR
operation, where core_tmr_drain_cmd_list() will now skip processing for this
case to prevent an ABORT_TASK status from being returned for descriptors that
are already queued up to be released by processing thread context.

Cc: Roland Dreier <roland@purestorage.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
2011-10-24 03:19:49 +00:00
Nicholas Bellinger d050ffb922 target: Re-org of core_tmr_lun_reset
This patch is a re-orginzation of core_tmr_lun_reset() logic to properly
scan the active tmr_list, dev->state_task_list and qobj->qobj_list w/ the
relivent locks held, and performing a list_move_tail onto seperate local
scope lists before performing the full drain.

This involves breaking out the code into three seperate list specific
functions: core_tmr_drain_tmr_list(), core_tmr_drain_task_list() and
core_tmr_drain_cmd_list().

(nab: Include target: Remove non-active tasks from execute list during
      LUN_RESET patch to address original breakage)

Reported-by: Roland Dreier <roland@purestorage.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
2011-10-24 03:19:32 +00:00
Roland Dreier 79a7fef264 target: Prevent cmd->se_queue_node double add
This patch addresses a bug with the lio-core-2.6.git conversion of
transport_add_cmd_to_queue() to use a single embedded list_head, instead
of individual struct se_queue_req allocations allowing a single se_cmd to
be added to the queue mulitple times.  This was changed in the following:

commit 2a9e4d5ca5d99f4c600578d6285d45142e7e5208
Author: Andy Grover <agrover@redhat.com>
Date:   Tue Apr 26 17:45:51 2011 -0700

    target: Embed qr in struct se_cmd

The problem is that some target code still assumes performing multiple
adds is allowed via transport_add_cmd_to_queue(), which ends up causing
list corruption in qobj->qobj_list code.  This patch addresses this
by removing an existing struct se_cmd from the list before the add, and
removes an unnecessary list walk in transport_remove_cmd_from_queue()

It also changes cmd->t_transport_queue_active to use explict sets intead
of increment/decrement to prevent confusion during exception path handling.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
2011-10-24 03:17:51 +00:00
Jesper Juhl 9375b1bfd2 target: Remove unneeded version.h includes
It was pointed out by 'make versioncheck' that some includes of
linux/version.h are not needed in drivers/target/.
This patch removes them.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-10-11 04:10:19 +00:00
Andy Grover 6708bb27bb target: Follow up core updates from AGrover and HCH (round 4)
This patch contains the squashed version of forth round series cleanups
from Andy and Christoph following the post heavy lifting in the preceeding:
'Eliminate usage of struct se_mem' and 'Make all control CDBs scatter-gather'
changes.  This also includes a conversion of target core and the v3.0
mainline fabric modules (loopback and tcm_fc) to use pr_debug and the
CONFIG_DYNAMIC_DEBUG infrastructure!

These have been squashed into this third and final round for v3.1.

target: Remove ifdeffed code in t_g_process_write
target: Remove direct ramdisk code
target: Rename task_sg_num to task_sg_nents
target: Remove custom debug macros for pr_debug. Use pr_err().
target: Remove custom debug macros in mainline fabrics
target: Set WSNZ=1 in block limits VPD. Abort if WRITE_SAME sectors = 0
target: Remove transport do_se_mem_map callback
target: Further simplify transport_free_pages
target: Redo task allocation return value handling
target: Remove extra parentheses
target: change alloc_task call to take *cdb, not *cmd

(nab: Fix bogus struct file assignments in fd_do_readv and fd_do_writev)

Signed-off-by: Andy Grover <agrover@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:48 +00:00
Roland Dreier 5e1be91982 target: Make se_tmr_lock IRQ-safe
transport_lookup_tmr_lun() can be called from interrupt context and
therefore needs to use IRQ-safe spinlock functions.  Fix this up, and
to make the locking work, convert the other uses of se_tmr_lock to be
IRQ-disabling.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:45 +00:00
Christoph Hellwig dc2e652d5f target: remove the always-noop ->new_cmd_failure method
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:44 +00:00
Andy Grover a1d8b49abd target: Updates from AGrover and HCH (round 3)
This patch contains a squashed version of third round series cleanups,
improvements ,and simplfications from Andy and Christoph ahead of the
heavy lifting between round 3 -> 4 for the target core SGL conversion.

This include cleanups to the main target I/O path and other miscellaneous
updates.

target: Replace custom sg<->buf functions with lib funcs
target: Simplify sector limiting code
target: get_cdb should never return NULL
target: Simplify transport_memcpy_se_mem_read_contig
target: Use assignment rather than increment for t_task_cdbs
target: Don't pass dma_size to generic_get_mem
target: Pass sg with type scatterlist in transport_map_sg_to_mem
target: Move task_sg_num next to task_sg in struct se_task
target: inline struct se_transport_task into struct se_cmd
target: Change name & semantics of transport_get_sectors()
target: Remove unused members of se_cmd
target: Rename se_cmd.t_task_cdbs to t_task_list_num
target: Fix some spelling
target: Remove unused var from transport_generic_do_tmr
target: map_sg_to_mem: return sg_count in return value
target/pscsi: Use min_t for sector limits
target/pscsi: Unused param for pscsi_get_bio()
target: Rename get_cdb_count to allocate_tasks
target: Make transport_generic_new_cmd() available for iscsi-target
target: Remove fabric callback to allocate iovecs
target: Fix transport_generic_new_cmd WRITE comment

(hch: Use __GFP_ZERO usage for alloc_pages() usage)

Signed-off-by: Andy Grover <agrover@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:44 +00:00
Andy Grover 5951146dea target: More core cleanups from AGrover (round 2)
This patch contains the squashed version of second round of target core
cleanups and simplifications and Andy and Co.   It also contains a handful
of fixes to address bugs the original series and other minor cleanups.

Here is the condensed shortlog:

target: Remove unneeded casts to void*
target: Rename get_lun_for_{cmd,tmr} to lookup_{cmd,tmr}_lun
target: Make t_task a member of se_cmd, not a pointer
target: Handle functions returning "-2"
target: Use cmd->se_dev over cmd->se_lun->lun_se_dev
target: Embed qr in struct se_cmd
target: Replace embedded struct se_queue_req with a list_head
target: Rename list_heads that are nodes in struct se_cmd to "*_node"
target: Fold transport_device_setup_cmd() into lookup_{tmr,cmd}_lun()
target: Make t_mem_list and t_mem_list_bidi members of t_task
target: Add comment & cleanup transport_map_sg_to_mem()
target: Remove unneeded checks in transport_free_pages()

(Roland: Fix se_queue_req removal leftovers OOPs)
(nab: Fix transport_lookup_tmr_lun failure case)
(nab: Fix list_empty(&cmd->t_task.t_mem_bidi_list) inversion bugs)

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:43 +00:00
Andy Grover e3d6f909ed target: Core cleanups from AGrover (round 1)
This patch contains the squashed version of a number of cleanups and
minor fixes from Andy's initial series (round 1) for target core this
past spring.  The condensed log looks like:

target: use errno values instead of returning -1 for everything
target: Rename transport_calc_sg_num to transport_init_task_sg
target: Fix leak in error path in transport_init_task_sg
target/pscsi: Remove pscsi_get_sh() usage
target: Make two runtime checks into WARN_ONs
target: Remove hba queue depth and convert to spin_lock_irq usage
target: dev->dev_status_queue_obj is unused
target: Make struct se_queue_req.cmd type struct se_cmd *
target: Remove __transport_get_qr_from_queue()
target: Rename se_dev->g_se_dev_list to se_dev_node
target: Remove struct se_global
target: Simplify scsi mib index table code
target: Make dev_queue_obj a member of se_device instead of a pointer
target: remove extraneous returns at end of void functions
target: Ensure transport_dump_vpd_ident_type returns null-terminated str
target: Function pointers don't need to use '&' to be assigned
target: Fix comment in __transport_execute_tasks()
target: Misc style cleanups
target: rename struct pr_reservation_template to pr_reservation
target: Remove #defines that just perform indirection
target: Inline transport_get_task_from_execute_queue()
target: Minor header comment fixes

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-07-22 09:37:43 +00:00
Nicholas Bellinger 7fd29aa920 target: Fix transport_get_lun_for_tmr failure cases
This patch fixes two possible NULL pointer dereferences in target v4.0
code where se_tmr release path in core_tmr_release_req() can OOPs upon
transport_get_lun_for_tmr() failure by attempting to access se_device or
se_tmr->tmr_list without a valid member of se_device->tmr_list during
transport_free_se_cmd() release.  This patch moves the se_tmr->tmr_dev
pointer assignment in transport_get_lun_for_tmr() until after possible
-ENODEV failures during unpacked_lun lookup.

This addresses an OOPs originally reported with LIO v4.1 upstream on
.39 code here:

    TARGET_CORE[qla2xxx]: Detected NON_EXISTENT_LUN Access for 0x00000000
    BUG: unable to handle kernel NULL pointer dereference at 0000000000000550
    IP: [<ffffffff81035ec4>] __ticket_spin_trylock+0x4/0x20
    PGD 0
    Oops: 0000 [#1] SMP
    last sysfs file: /sys/devices/system/cpu/cpu23/cache/index2/shared_cpu_map
    CPU 1
    Modules linked in: netconsole target_core_pscsi target_core_file
tcm_qla2xxx target_core_iblock tcm_loop target_core_mod configfs
ipmi_devintf ipmi_si ipmi_msghandler serio_raw i7core_edac ioatdma dca
edac_core ps_bdrv ses enclosure usbhid usb_storage ahci qla2xxx hid
uas e1000e mpt2sas libahci mlx4_core scsi_transport_fc
scsi_transport_sas raid_class scsi_tgt [last unloaded: netconsole]

    Pid: 0, comm: kworker/0:0 Tainted: G        W   2.6.39+ #1 Xyratex Storage Server
    RIP: 0010:[<ffffffff81035ec4>] [<ffffffff81035ec4>]__ticket_spin_trylock+0x4/0x20
    RSP: 0018:ffff88063e803c08  EFLAGS: 00010286
    RAX: ffff880619ab45e0 RBX: 0000000000000550 RCX: 0000000000000000
    RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000550
    RBP: ffff88063e803c08 R08: 0000000000000002 R09: 0000000000000000
    R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000568
    R13: 0000000000000001 R14: 0000000000000000 R15: ffff88060cd96a20
    FS:  0000000000000000(0000) GS:ffff88063e800000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
    CR2: 0000000000000550 CR3: 0000000001a03000 CR4: 00000000000006e0
    DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
    DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
    Process kworker/0:0 (pid: 0, threadinfo ffff880619ab8000, task ffff880619ab45e0)
    Stack:
     ffff88063e803c28 ffffffff812cf039 0000000000000550 0000000000000568
     ffff88063e803c58 ffffffff8157071e ffffffffa028a1dc ffff88060f7e4600
     0000000000000550 ffff880616961480 ffff88063e803c78 ffffffffa028a1dc
    Call Trace:
<IRQ>
     [<ffffffff812cf039>] do_raw_spin_trylock+0x19/0x50
     [<ffffffff8157071e>] _raw_spin_lock+0x3e/0x70
     [<ffffffffa028a1dc>] ? core_tmr_release_req+0x2c/0x60 [target_core_mod]
     [<ffffffffa028a1dc>] core_tmr_release_req+0x2c/0x60 [target_core_mod]
     [<ffffffffa028d0d2>] transport_free_se_cmd+0x22/0x50 [target_core_mod]
     [<ffffffffa028d120>] transport_release_cmd_to_pool+0x20/0x40 [target_core_mod]
     [<ffffffffa028e525>] transport_generic_free_cmd+0xa5/0xb0 [target_core_mod]
     [<ffffffffa0147cc4>] tcm_qla2xxx_handle_tmr+0xc4/0xd0 [tcm_qla2xxx]
     [<ffffffffa0191ba3>] __qla24xx_handle_abts+0xd3/0x150 [qla2xxx]
     [<ffffffffa0197651>] qla_tgt_response_pkt+0x171/0x520 [qla2xxx]
     [<ffffffffa0197a2d>] qla_tgt_response_pkt_all_vps+0x2d/0x220 [qla2xxx]
     [<ffffffffa0171dd3>] qla24xx_process_response_queue+0x1a3/0x670 [qla2xxx]
     [<ffffffffa0196281>] ? qla24xx_atio_pkt+0x81/0x120 [qla2xxx]
     [<ffffffffa0174025>] ? qla24xx_msix_default+0x45/0x2a0 [qla2xxx]
     [<ffffffffa0174198>] qla24xx_msix_default+0x1b8/0x2a0 [qla2xxx]
     [<ffffffff810dadb4>] handle_irq_event_percpu+0x54/0x210
     [<ffffffff810dafb8>] handle_irq_event+0x48/0x70
     [<ffffffff810dd5ee>] ? handle_edge_irq+0x1e/0x110
     [<ffffffff810dd647>] handle_edge_irq+0x77/0x110
     [<ffffffff8100d362>] handle_irq+0x22/0x40
     [<ffffffff8157b28d>] do_IRQ+0x5d/0xe0
     [<ffffffff81571413>] common_interrupt+0x13/0x13
<EOI>
     [<ffffffff813003f7>] ? intel_idle+0xd7/0x130
     [<ffffffff813003f0>] ? intel_idle+0xd0/0x130
     [<ffffffff8144832b>] cpuidle_idle_call+0xab/0x1c0
     [<ffffffff8100a26b>] cpu_idle+0xab/0xf0
     [<ffffffff81566c59>] start_secondary+0x1cb/0x1d2

Reported-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-06-23 23:59:45 +00:00
Nicholas Bellinger 1e7de68c57 [SCSI] target: Fix interrupt context bug with stats_lock and core_tmr_alloc_req
This patch fixes two bugs wrt to the interrupt context usage of target
core with HW target mode drivers.  It first converts the usage of struct
se_device->stats_lock in transport_get_lun_for_cmd() and core_tmr_lun_reset()
to properly use spin_lock_irq() to address an BUG with CONFIG_LOCKDEP_SUPPORT=y
enabled.

This patch also adds a 'in_interrupt()' check to allow GFP_ATOMIC usage from
core_tmr_alloc_req() to fix a 'sleeping in interrupt context' BUG with HW
target fabrics that require this logic to function.

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Cc: stable@kernel.org
Signed-off-by: James Bottomley <jbottomley@parallels.com>
2011-05-27 11:49:25 +00:00
Nicholas Bellinger 52208ae3fc [SCSI] target: Fix t_transport_aborted handling in LUN_RESET + active I/O shutdown
This patch addresses two outstanding bugs related to
T_TASK(cmd)->t_transport_aborted handling during TMR LUN_RESET and
active I/O shutdown.

This first involves adding two explict t_transport_aborted=1
assignments in core_tmr_lun_reset() in order to signal the task has
been aborted, and updating transport_generic_wait_for_tasks() to skip
sleeping when t_transport_aborted=1 has been set.  This fixes an issue
where transport_generic_wait_for_tasks() would end up sleeping
indefinately when called from fabric module context while TMR
LUN_RESET was happening with long outstanding backend struct se_task
not yet being completed.

The second adds a missing call to
transport_remove_task_from_execute_queue() when
task->task_execute_queue=1 is set in order to fix an OOPs when
task->t_execute_list has not been dropped.  It also fixes the same
case in transport_processing_shutdown() to prevent the issue from
happening during active I/O struct se_device shutdown.

Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-02-28 11:23:32 -06:00
Nicholas Bellinger c66ac9db8d [SCSI] target: Add LIO target core v4.0.0-rc6
LIO target is a full featured in-kernel target framework with the
following feature set:

High-performance, non-blocking, multithreaded architecture with SIMD
support.

Advanced SCSI feature set:

    * Persistent Reservations (PRs)
    * Asymmetric Logical Unit Assignment (ALUA)
    * Protocol and intra-nexus multiplexing, load-balancing and failover (MC/S)
    * Full Error Recovery (ERL=0,1,2)
    * Active/active task migration and session continuation (ERL=2)
    * Thin LUN provisioning (UNMAP and WRITE_SAMExx)

Multiprotocol target plugins

Storage media independence:

    * Virtualization of all storage media; transparent mapping of IO to LUNs
    * No hard limits on number of LUNs per Target; maximum LUN size ~750 TB
    * Backstores: SATA, SAS, SCSI, BluRay, DVD, FLASH, USB, ramdisk, etc.

Standards compliance:

    * Full compliance with IETF (RFC 3720)
    * Full implementation of SPC-4 PRs and ALUA

Significant code cleanups done by Christoph Hellwig.

[jejb: fix up for new block bdev exclusive interface. Minor fixes from
 Randy Dunlap and Dan Carpenter.]
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-01-14 10:12:29 -06:00