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>
All ->execute_task instances now need to complete the I/O explicitly,
which can either happen synchronously or asynchronously.
Note that a lot of the CDB emulations appear to return success even if
some lowlevel operations failed. Given that this is an existing issue
this patch doesn't change that fact.
(nab: Adding missing switch breaks in PR-IN + PR_OUT)
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
We want to be able to handle all CDBs through it and remove hacks like
always using the first task in a CDB in target_report_luns.
Also rename the callback to ->execute_task to better describe its use.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch adds the initial pieces of generic active I/O shutdown logic.
This is intended to be a 'opt-in' feature for fabric modules that
includes the following functions to provide a mechinism for fabric
modules to track se_cmd via se_session->sess_cmd_list:
*) target_get_sess_cmd() - Add se_cmd to sess->sess_cmd_list, called
from fabric module incoming I/O path.
*) target_put_sess_cmd() - Check for completion or drop se_cmd from
->sess_cmd_list
*) target_splice_sess_cmd_list() - Splice active I/O list from
->sess_cmd_list to ->sess_wait_list, can called with HW fabric
lock held.
*) target_wait_for_sess_cmds() - Walk ->sess_wait_list waiting on
individual ->cmd_wait_comp. Optional transport_wait_for_tasks()
call.
target_splice_sess_cmd_list() is allowed to be called under HW fabric
lock, and performs the splice into se_sess->sess_wait_list and set
se_cmd->cmd_wait_set. Then target_wait_for_sess_cmds() walks the list
waiting for individual target_put_sess_cmd() fabric callbacks to
complete.
It also adds TFO->check_release_cmd() to split the completion and memory
release calls, where a fabric module uses target_put_sess_cmd() to check
for I/O completion during session shutdown. This is currently pushed out
into fabric modules as current fabric code may sleep here waiting for
TFO->check_stop_free() to complete in main response path, and because
target_wait_for_sess_cmds() calling TFO->release_cmd() to free fabric
descriptor memory directly.
Cc: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
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>
This patch converts target_core_fabric_ops->check_stop_free() usage in
transport_cmd_check_stop() and associated fabric module usage to
return '1' when the passed se_cmd has been released directly within
->check_stop_free(), or return '0' when the passed se_cmd has not
been released.
This addresses an issue where transport_cmd_finish_abort() ->
transport_cmd_check_stop_to_fabric() was leaking descriptors during
LUN_RESET for modules using ->check_stop_free(), but not directly
releasing se_cmd in all cases.
Cc: stable@kernel.org
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (59 commits)
MAINTAINERS: linux-m32r is moderated for non-subscribers
linux@lists.openrisc.net is moderated for non-subscribers
Drop default from "DM365 codec select" choice
parisc: Kconfig: cleanup Kernel page size default
Kconfig: remove redundant CONFIG_ prefix on two symbols
cris: remove arch/cris/arch-v32/lib/nand_init.S
microblaze: add missing CONFIG_ prefixes
h8300: drop puzzling Kconfig dependencies
MAINTAINERS: microblaze-uclinux@itee.uq.edu.au is moderated for non-subscribers
tty: drop superfluous dependency in Kconfig
ARM: mxc: fix Kconfig typo 'i.MX51'
Fix file references in Kconfig files
aic7xxx: fix Kconfig references to READMEs
Fix file references in drivers/ide/
thinkpad_acpi: Fix printk typo 'bluestooth'
bcmring: drop commented out line in Kconfig
btmrvl_sdio: fix typo 'btmrvl_sdio_sd6888'
doc: raw1394: Trivial typo fix
CIFS: Don't free volume_info->UNC until we are entirely done with it.
treewide: Correct spelling of successfully in comments
...
This patch removes the legacy usage of se_task->task_timer and associated
infrastructure that originally was used as a way to help manage buggy backend
SCSI LLDs that in certain cases would never return back an outstanding task.
This includes the removal of target_complete_timeout_work(), timeout logic
from transport_complete_task(), transport_task_timeout_handler(),
transport_start_task_timer(), the per device task_timeout configfs attribute,
and all task_timeout associated structure members and defines in
target_core_base.h
This is being removed in preparation to make transport_complete_task() run
in lock-less mode.
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch converts target-core to use se_cmd->t_transport_sent instead of
a duplicated se_cmd->transport_sent member in a handful of locations.
It also updates iscsi_target to properly use ->t_transport_sent instead of
it's own iscsi_cmd_t->transport_sent value that was not being assigned.
Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This field is never used given that BIDI handling happens at the
command and not the task level. Remove it and the dead code in
pscsi that tries to work on it.
It also prevents pSCSI passthrough for the two currently enabled BIDI
commands now that task->task_sg_bidi support has been removed.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Remove the now unnecessary extra call to transport_subsystem_check_init() in
target_core_register_fabric(), and also merge transport_subsystem_reqmods()
directly into transport_subsystem_check_init().
Reported-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
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>
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>
We never queue an command with this state, and only set it in a completely
bogus place in tcm_fc.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Currently we stop the timers for all tasks in a command fairly late during
I/O completion, which is fairly pointless and requires all kinds of safety
checks.
Instead delete pending timers early on in transport_complete_task, thus
ensuring no new timers firest after that. We take t_state_lock a bit later
in that function thus making sure currenly running timers are out of the
criticial section. To be completely sure the timer has finished we also
add another del_timer_sync call when freeing the task.
This also allows removing TF_TIMER_RUNNING as it would be equivalent
to TF_ACTIVE now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
TF_TIMER_STOP is useless as it only helps to mitigate a tiny race during
deleting the timer. But given that we have cleared TF_ACTIVE at this point
we already have another mitigation a few lines down the function.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Add a new boolean at_head parameter to transport_add_cmd_to_queue and thus
obsolete the SCF_EMULATE_QUEUE_FULL flag.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Remove the need for the transport_qf_callback callback by making
sure we have specific states with specific handlers for the two
queue full cases.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Remove the dpo_emulated, fua_write_emulated, fua_read_emulated and
write_cache_emulated methods, and replace them with a simple bitfields in
se_subsystem_api in those cases where they ever returned one.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Add a switch statement implementing the CDB LBA/len update directly
in target_get_task_cdb and remove the old ->transport_split_cdb
callback and all its implementations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Instead of calling out to the backends from the core to get a per-task
CDB and then modify it for the LBA/len pair used for this CDB provide
a helper that writes the adjusted CDB into a provided buffer and call
this method from ->do_task in pscsi.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Rearrange the fields in se_task to avoid holes. Also increase the
flags field to 16 bits as we have the space for it, and this makes
adding new flags safer.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
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>
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>
This is a squashed version of the following se_task cleanup patches:
target: remove the unused task_state_flags field in se_task
target: remove the unused se_obj_ptr field in se_task
target: remove the se_dev field in se_task
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This is a squashed version of the following target_core_base.h
cleanup patches:
target: remove the unused SHUTDOWN_SIGS defintion
target: remove unused se_mem leftovers
target: remove the unused map_func_t typedef
target: move TRANSPORT_IOV_DATA_BUFFER to the iscsi-specific code
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
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>
This patch converts se_cmd->transport_wait_for_tasks(se_cmd, 1) usage to use
transport_generic_free_cmd() directly in target-core and iscsi-target fabric
usage. The includes:
*) Removal of the optional transport_generic_free_cmd() call from within
transport_generic_wait_for_tasks()
*) Usage of existing SCF_SUPPORTED_SAM_OPCODE to determine when
transport_generic_wait_for_tasks() processing may occur instead of
checking se_cmd->transport_wait_for_tasks()
*) Move transport_generic_wait_for_tasks() call ahead of core_dec_lacl_count()
and transport_lun_remove_cmd() in transport_generic_free_cmd() to follow
existing logic for iscsi-target w/ se_cmd->transport_wait_for_tasks(se_cmd, 1)
*) Removal of se_cmd->transport_wait_for_tasks() function pointer
*) Rename transport_generic_wait_for_tasks() -> transport_wait_for_tasks(), and
add docbook comment.
*) Add EXPORT_SYMBOL for transport_wait_for_tasks()
For the case in iscsi_target_erl2.c:iscsit_prepare_cmds_for_realligance()
where se_cmd->transport_wait_for_tasks(se_cmd, 0) is called, this patch
adds a direct call to transport_wait_for_tasks().
(hch: Fix transport_generic_free_cmd() usage in iscsit_release_commands_from_conn)
(nab: Add patch: Ensure that TMRs hit wait_for_tasks logic during release)
Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
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>
The cdb_none, map_data_SG and map_control_SG methods have no callers left
and can be removed now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch removes the unnecessary session_reinstatement parameter from
se_cmd->transport_wait_for_tasks(), logic in transport_generic_wait_for_tasks,
and usage within iscsi-target code.
This also includes the removal of the 'bool' return from transport_put_cmd() +
transport_generic_free_cmd() that is no longer necessary.
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Push session reinstatement out of transport_generic_free_cmd into the only
caller that actually needs it. Clean up transport_generic_free_cmd a bit,
and remove the useless comment. I'd love to add a more useful kerneldoc
comment for it, but as this point I'm still a bit confused in where it
stands in the command release stack.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
It is only called by transport_release_cmd, so inline it there. Also add
a kerneldoc comment for transport_release_cmd while we are at it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
There are numerous broken references to Documentation files (in other
Documentation files, in comments, etc.). These broken references are
caused by typo's in the references, and by renames or removals of the
Documentation files. Some broken references are simply odd.
Fix these broken references, sometimes by dropping the irrelevant text
they were part of.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This patch changes target_emulate_inquiry_std() to set the 'not connected'
(0x35) bit in standard INQUIRY response data when we are processing a
request to a virtual LUN=0 mapping from struct se_device *g_lun0_dev that
have been setup for us in transport_lookup_cmd_lun().
This addresses an issue where qla2xxx FC clients need to be able
to create demo-mode I_T FC Nexuses by default, but should not be
exposing the default set of TPG LUNs to all FC clients. This includes
adding an new optional target_core_fabric_ops->tpg_check_demo_mode_login_only()
caller to allow demo_mode nexuses to skip the old default of bulding
a demo-mode MappedLUNs list via core_tpg_add_node_to_devs().
(roland: Add missing tpg_check_demo_mode_login_only check in core_dev_add_lun)
Reported-by: Roland Dreier <roland@purestorage.com>
Cc: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
This patch bumps the target core version to v4.1.0-rc1 now that we are
in sync with upstream lio-core-2.6.git/master
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch drops transport_asciihex_to_binaryhex() in favor of proper
hex2bin usage from include/linux/kernel.h:hex2bin()
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch adds the default 'Unrestricted reordering allowed' for SCSI
control mode page QUEUE ALGORITHM MODIFIER on a per se_device basis in
target_modesense_control() following spc4r23. This includes a new
emuluate_rest_reord configfs attribute that currently (only) accepts
zero to signal 'Unrestricted reordering allowed' in control mode page
usage by the backend target device.
Reported-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>
This patch breaks up the ->map_task_SG() backend call into two seperate
->map_control_SG() and ->map_data_SG() in order to better address
IBLOCK and pSCSI. IBLOCK only allocates bios for ->map_data_SG(), and
pSCSI will allocate a struct request for both cases.
This patch fixes incorrect usage of ->map_task_SG() for all se_cmd descriptors
in transport_generic_new_cmd() by moving the call into it's proper location
directly inside of transport_allocate_data_tasks()
Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
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>
Both backstores and fabrics use arrays of struct scatterlist to describe
data buffers. However TCM used struct se_mems, basically a linked list
of scatterlist entries. We are able to simplify the code by eliminating
this intermediate data structure and just using struct scatterlist[]
throughout.
Also, moved attachment of task to cmd out of transport_generic_get_task
and into allocate_control_task and allocate_data_tasks. The reasoning
is that it's nonintuitive that get_task should automatically add it to
the cmd's task list -- it should just return an allocated, initialized
task. That's all it should do, based on the function's name, so either the
function shouldn't do it, or the name should change to encapsulate the
entire essence of what it does.
(nab: Fix compile warnings in tcm_fc, and make transport_kmap_first_data_page
honor sg->offset for SGLs from contigious memory with TCM_Loop, and
fix control se_cmd descriptor memory leak)
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Since sectors is not modified, it's more straightforward to do this.
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Due to all cdbs' data buffers being referenced by scatterlists, buffers
of more than a page are not contiguous. Instead of handling this in all
control command handlers, we may be able to get away with just limiting
control cdb data buffers to one page. The only control CDBs we handle that
have potentially large data buffers are REPORT LUNS and UNMAP, so if we
didn't want to live with this limitation, they would need to be modified
to walk the pages in the data buffer's sgl.
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Previously, some control CDBs did not allocate memory in pages for their
data buffer, but just did a kmalloc. This patch makes all cdbs allocate
pages.
This has the benefit of streamlining some paths that had to behave
differently when we used two allocation methods. The downside is that
all accesses to the data buffer need to kmap it before use, and need to
handle data in page-sized chunks if more than a page is needed for a given
command's data buffer.
Finally, note that cdbs with no data buffers are handled a little
differently. Before, SCSI_NON_DATA_CDBs would not call get_mem at all
(they'd be in the final else in transport_allocate_resources) but now
these will make it into generic_get_mem, but just not allocate any
buffers.
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Implement page B1h, Block Device Characteristics, so that we can report
a medium rotation rate of 1 (non-rotating / solid state) if the
is_nonrot device attribute is set; we update the iblock backend to set
this attribute if the underlying Linux block device has its nonrot
flag set.
Signed-off-by: Roland Dreier <roland@purestorage.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch adds SCF_EMULATE_QUEUE_FULL support using -EAGAIN failures
via transport_handle_queue_full() to signal queue full in completion
path TFO->queue_data_in() and TFO->queue_status() callbacks.
This is done using a new se_cmd->transport_qf_callback() to handle
the following queue full exception cases within target core:
*) TRANSPORT_COMPLETE_OK (for completion path queue full)
*) TRANSPORT_COMPLETE_QF_WP (for TRANSPORT_WRITE_PENDING queue full)
*) transport_send_check_condition_and_sense() failure paths in
transport_generic_request_failure() and transport_generic_complete_ok()
All logic is driven using se_device->qf_work_queue -> target_qf_do_work()
to to requeue outstanding se_cmd at the head of se_dev->queue_obj->qobj_list
for transport_processing_thread() execution.
Tested using tcm_qla2xxx with MAX_OUTSTANDING_COMMANDS=128 for FCP READ
to trigger the TRANSPORT_COMPLETE_OK queue full cases, and a simulated
TFO->write_pending() -EAGAIN failure to trigger TRANSPORT_COMPLETE_QF_WP.
Reported-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Nicholas Bellinger