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 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>
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>
The release_cmd_to_pool and release_cmd_direct methods are always the same.
Merge them into a single release_cmd method, and clean up the fallout.
(nab: fix breakage in transport_generic_free_cmd() parameter build breakage
in drivers/target/tcm_fc/tfc_cmd.c)
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
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>
This patch converts transport_core_report_lun_response() to use
drivers/scsi/scsi_scan.c:int_to_scsilun instead of using the
struct target_core_fabric_ops->pack_lun() fabric provided API vector.
It also removes the tfo->pack_lun check from target_fabric_tf_ops_check()
and removes from struct target_core_fabric_ops->pack_lun() from
target_core_fabric_ops.h, and the following mainline scsi-misc fabric
modules:
*) tcm_loop: Drop tcm_loop_pack_lun() usage
*) tcm_fc: Drop ft_pack_lun() usage
Reported-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <jbottomley@parallels.com>
This patch addresses the majority of sparse warnings and adds
proper locking annotations. It also fixes the dubious one-bit signed
bitfield, for which the signed one-bit types can be 0 or -1 which can
cause a problem if someone ever checks if (foo->lu_gp_assoc == 1).
The current code is fine because everyone just checks zero vs non-zero.
But Sparse complains about it so lets change it. The warnings look like
this:
include/target/target_core_base.h:228:26: error: dubious one-bit signed bitfield
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Fubo Chen <fubo.chen@gmail.com>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
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>
Nicholas Bellinger