path: root/Documentation/target
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2020-12-08tweewide: Fix most Shebang linesFinn Behrens
Change every shebang which does not need an argument to use /usr/bin/env. This is needed as not every distro has everything under /usr/bin, sometimes not even bash. Signed-off-by: Finn Behrens <> Signed-off-by: Masahiro Yamada <>
2020-06-13doc: don't use deprecated "---help---" markers in target docsLinus Torvalds
I'm not convinced the script makes useful automaed help lines anyway, but since we're trying to deprecate the use of "---help---" in Kconfig files, let's fix the doc example code too. See commit a7f7f6248d97 ("treewide: replace '---help---' in Kconfig files with 'help'") Cc: Masahiro Yamada <> Signed-off-by: Linus Torvalds <>
2020-03-20docs: prevent warnings due to autosectionlabelMauro Carvalho Chehab
Changeset 58ad30cf91f0 ("docs: fix reference to core-api/namespaces.rst") enabled a new feature at Sphinx: it will now generate index for each document title, plus to each chapter inside it. There's a drawback, though: one document cannot have two sections with the same name anymore. A followup patch will change the logic of autosectionlabel to avoid most creating references for every single section title, but still we need to be able to reference the chapters inside a document. There are a few places where there are two chapters with the same name. This patch renames one of the chapters, in order to avoid symbol conflict within the same document. PS.: as I don't speach Chinese, I had some help from a friend (Wen Liu) at the Chinese translation for "publishing patches" for this document: Documentation/translations/zh_CN/process/5.Posting.rst Fixes: 58ad30cf91f0 ("docs: fix reference to core-api/namespaces.rst") Signed-off-by: Mauro Carvalho Chehab <> Link: Signed-off-by: Jonathan Corbet <>
2019-07-15docs: add some directories to the main documentation indexMauro Carvalho Chehab
The contents of those directories were orphaned at the documentation body. While those directories could likely be moved to be inside some guide, I'm opting to just adding their indexes to the main one, removing the :orphan: and adding the SPDX header. For the drivers, the rationale is that the documentation contains a mix of Kernelspace, uAPI and admin-guide. So, better to keep them on separate directories, as we've be doing with similar subsystem-specific docs that were not split yet. For the others, well... I'm too lazy to do the move. Also, it seems to make sense to keep at least some of those at the main dir (like kbuild, for example). In any case, a latter patch could do the move. Signed-off-by: Mauro Carvalho Chehab <> Acked-by: Bartlomiej Zolnierkiewicz <>
2019-06-14docs: target: convert docs to ReST and rename to *.rstMauro Carvalho Chehab
Convert the TCM docs to ReST format and add them to the bookset. This has a mix of userspace-faced and Kernelspace faced docs. Still, it sounds a better candidate to be added at the kernel API set of docs. The conversion is actually: - add blank lines and identation in order to identify paragraphs; - fix tables markups; - add some lists markups; - mark literal blocks; - adjust title markups. At its new index.rst, let's add a :orphan: while this is not linked to the main index.rst file, in order to avoid build warnings. Signed-off-by: Mauro Carvalho Chehab <> Signed-off-by: Jonathan Corbet <>
2019-02-04scsi: target/core: Remove the write_pending_status() callback functionBart Van Assche
Due to the patch that makes TMF handling synchronous the write_pending_status() callback function is no longer called. Hence remove it. Acked-by: Felipe Balbi <> Reviewed-by: Sagi Grimberg <> Reviewed-by: Andy Grover <> Reviewed-by: Christoph Hellwig <> Reviewed-by: Hannes Reinecke <> Reviewed-by: Bryant G. Ly <> Cc: Nicholas Bellinger <> Cc: Mike Christie <> Cc: Himanshu Madhani <> Cc: Quinn Tran <> Cc: Saurav Kashyap <> Cc: Michael S. Tsirkin <> Cc: Juergen Gross <> Signed-off-by: Bart Van Assche <> Signed-off-by: Martin K. Petersen <>
2017-05-01Documentation/target: add an example script to configure an iSCSI targetChristophe Vu-Brugier
The script illustrates how to interact with configfs to create a very simple LIO iSCSI target with a file or block device backstore. The script can serve as a starting point for people that cannot use targetcli because Python is not available on their machine. Signed-off-by: Christophe Vu-Brugier <> Signed-off-by: Vincent Donnefort <> Signed-off-by: Nicholas Bellinger <>
2016-05-10target: make close_session optionalChristoph Hellwig
Signed-off-by: Christoph Hellwig <> Signed-off-by: Nicholas Bellinger <>
2016-05-10target: make ->shutdown_session optionalChristoph Hellwig
Turns out the template and thus many drivers got the return value wrong: 0 means the fabrics driver needs to put a session reference, which no driver except for the iSCSI target drivers did. Fortunately none of these drivers supports explicit Node ACLs, so the bug was harmless. Even without that only qla2xxx and iscsi every did real work in shutdown_session, so get rid of the boilerplate code in all other drivers. Signed-off-by: Christoph Hellwig <> Signed-off-by: Nicholas Bellinger <>
2016-03-10target/user: Report capability of handling out-of-order completions to userspaceSheng Yang
TCMU_MAILBOX_FLAG_CAP_OOOC was introduced, and userspace can check the flag for out-of-order completion capability support. Also update the document on how to use the feature. Signed-off-by: Sheng Yang <> Reviewed-by: Andy Grover <> Signed-off-by: Nicholas Bellinger <>
2015-10-13target: use per-attribute show and store methodsChristoph Hellwig
This also allows to remove the target-specific old configfs macros, and gets rid of the target_core_fabric_configfs.h header which only had one function declaration left that could be moved to a better place. Signed-off-by: Christoph Hellwig <> Reviewed-by: Nicholas Bellinger <> Acked-by: Nicholas Bellinger <> Signed-off-by: Nicholas Bellinger <>
2015-07-24Documentation/target: Fix build breakageSebastian Herbszt
Fix build breakage and set the protocol identifier based on the parameter. Fixes: 9ac8928e6a3e ("target: simplify the target template registration API") Fixes: e4aae5af810e ("target: change core_tpg_register prototype") Signed-off-by: Sebastian Herbszt <> Reviewed-by: Christoph Hellwig <> Signed-off-by: Nicholas Bellinger <>
2015-07-04Merge branch 'for-next' of ↵Linus Torvalds
git:// Pull SCSI target updates from Nicholas Bellinger: "It's been a busy development cycle for target-core in a number of different areas. The fabric API usage for se_node_acl allocation is now within target-core code, dropping the external API callers for all fabric drivers tree-wide. There is a new conversion to RCU hlists for se_node_acl and se_portal_group LUN mappings, that turns fast-past LUN lookup into a completely lockless code-path. It also removes the original hard-coded limitation of 256 LUNs per fabric endpoint. The configfs attributes for backends can now be shared between core and driver code, allowing existing drivers to use common code while still allowing flexibility for new backend provided attributes. The highlights include: - Merge sbc_verify_dif_* into common code (sagi) - Remove iscsi-target support for obsolete IFMarker/OFMarker (Christophe Vu-Brugier) - Add bidi support in target/user backend (ilias + vangelis + agover) - Move se_node_acl allocation into target-core code (hch) - Add crc_t10dif_update common helper (akinobu + mkp) - Handle target-core odd SGL mapping for data transfer memory (akinobu) - Move transport ID handling into target-core (hch) - Move task tag into struct se_cmd + support 64-bit tags (bart) - Convert se_node_acl->device_list[] to RCU hlist (nab + hch + paulmck) - Convert se_portal_group->tpg_lun_list[] to RCU hlist (nab + hch + paulmck) - Simplify target backend driver registration (hch) - Consolidate + simplify target backend attribute implementations (hch + nab) - Subsume se_port + t10_alua_tg_pt_gp_member into se_lun (hch) - Drop lun_sep_lock for se_lun->lun_se_dev RCU usage (hch + nab) - Drop unnecessary core_tpg_register TFO parameter (nab) - Use 64-bit LUNs tree-wide (hannes) - Drop left-over TARGET_MAX_LUNS_PER_TRANSPORT limit (hannes)" * 'for-next' of git:// (76 commits) target: Bump core version to v5.0 target: remove target_core_configfs.h target: remove unused TARGET_CORE_CONFIG_ROOT define target: consolidate version defines target: implement WRITE_SAME with UNMAP bit using ->execute_unmap target: simplify UNMAP handling target: replace se_cmd->execute_rw with a protocol_data field target/user: Fix inconsistent kmap_atomic/kunmap_atomic target: Send UA when changing LUN inventory target: Send UA upon LUN RESET tmr completion target: Send UA on ALUA target port group change target: Convert se_lun->lun_deve_lock to normal spinlock target: use 'se_dev_entry' when allocating UAs target: Remove 'ua_nacl' pointer from se_ua structure target_core_alua: Correct UA handling when switching states xen-scsiback: Fix compile warning for 64-bit LUN target: Remove TARGET_MAX_LUNS_PER_TRANSPORT target: use 64-bit LUNs target: Drop duplicate + unused se_dev_check_wce target: Drop unnecessary core_tpg_register TFO parameter ...
2015-06-23Merge tag 'scsi-misc' of git:// Torvalds
Pull SCSI updates from James Bottomley: "This is the usual grab bag of driver updates (lpfc, hpsa, megaraid_sas, cxgbi, be2iscsi) plus an assortment of minor updates. There is also one new driver: the Cisco snic. The advansys driver has been rewritten to get rid of the warning about converting it to the DMA API, the tape statistics patch got in and finally, there's a resuffle of SCSI header files to separate more cleanly initiator from target mode (and better share the common definitions)" * tag 'scsi-misc' of git:// (156 commits) snic: driver for Cisco SCSI HBA qla2xxx: Fix indentation qla2xxx: Comment out unreachable code fusion: remove dead MTRR code advansys: fix compilation errors and warnings when CONFIG_PCI is not set mptsas: fix depth param in scsi_track_queue_full megaraid: fix irq setup process regression lpfc: Update version to for upstream patch set. lpfc: Fix to drop PLOGIs from fabric node till LOGO processing completes lpfc: Fix scsi task management error message. lpfc: Fix cq_id masking problem. lpfc: Fix scsi prep dma buf error. lpfc: Add support for using block multi-queue lpfc: Devices are not discovered during takeaway/giveback testing lpfc: Fix vport deletion failure. lpfc: Check for active portpeerbeacon. lpfc: Update driver version for upstream patch set lpfc: Change buffer pool empty message to miscellaneous category lpfc: Fix incorrect log message reported for empty FCF record. lpfc: Fix rport leak. ...
2015-06-02target: Minimize SCSI header #include directivesBart Van Assche
Only include SCSI initiator header files in target code that needs these header files, namely the SCSI pass-through code and the tcm_loop driver. Change SCSI_SENSE_BUFFERSIZE into TRANSPORT_SENSE_BUFFER in target code because the former is intended for initiator code and the latter for target code. With this patch the only initiator include directives in target code that remain are as follows: $ git grep -nHE 'include .scsi/(scsi.h|scsi_host.h|scsi_device.h|scsi_cmnd.h)' drivers/target drivers/infiniband/ulp/{isert,srpt} drivers/usb/gadget/legacy/tcm_*.[ch] drivers/{vhost,xen} include/{target,trace/events/target.h} drivers/target/loopback/tcm_loop.c:29:#include <scsi/scsi.h> drivers/target/loopback/tcm_loop.c:31:#include <scsi/scsi_host.h> drivers/target/loopback/tcm_loop.c:32:#include <scsi/scsi_device.h> drivers/target/loopback/tcm_loop.c:33:#include <scsi/scsi_cmnd.h> drivers/target/target_core_pscsi.c:39:#include <scsi/scsi_device.h> drivers/target/target_core_pscsi.c:40:#include <scsi/scsi_host.h> drivers/xen/xen-scsiback.c:52:#include <scsi/scsi_host.h> /* SG_ALL */ Signed-off-by: Bart Van Assche <> Reviewed-by: Christoph Hellwig <> Signed-off-by: James Bottomley <>
2015-05-30target: target_core_configfs.h is not needed in fabric driversChristoph Hellwig
Signed-off-by: Christoph Hellwig <> Signed-off-by: Nicholas Bellinger <>
2015-05-30target: Move task tag into struct se_cmd + support 64-bit tagsBart Van Assche
Simplify target core and target drivers by storing the task tag a.k.a. command identifier inside struct se_cmd. For several transports (e.g. SRP) tags are 64 bits wide. Hence add support for 64-bit tags. (Fix core_tmr_abort_task conversion spec warnings - nab) (Fix up usb-gadget to use 16-bit tags - HCH + bart) Signed-off-by: Bart Van Assche <> Cc: Christoph Hellwig <> Cc: Andy Grover <> Cc: Sagi Grimberg <> Cc: <> Cc: Felipe Balbi <> Cc: Michael S. Tsirkin <> Cc: Juergen Gross <> Signed-off-by: Nicholas Bellinger <>
2015-05-30target: move transport ID handling to the coreChristoph Hellwig
Now that struct se_portal_group contains a protocol identifier field we can take all the code to format an parse protocol identifiers in CDBs into common code instead of leaving this to low-level drivers. Signed-off-by: Christoph Hellwig <> Signed-off-by: Nicholas Bellinger <>
2015-05-30target: remove the get_fabric_proto_ident methodChristoph Hellwig
Now that we store the protocol identifier in the tpg structure we don't need this method. Signed-off-by: Christoph Hellwig <> Signed-off-by: Nicholas Bellinger <>
2015-05-30target: change core_tpg_register prototypeChristoph Hellwig
Remove the unneeded fabric_ptr argument, and change the type argument to pass in a SPC protocol identifier. Signed-off-by: Christoph Hellwig <> Signed-off-by: Nicholas Bellinger <>
2015-05-30target: move node ACL allocation to core codeChristoph Hellwig
Signed-off-by: Christoph Hellwig <> Signed-off-by: Nicholas Bellinger <>
2015-05-30target: refactor init/drop_nodeacl methodsChristoph Hellwig
By always allocating and adding, respectively removing and freeing the se_node_acl structure in core code we can remove tons of repeated code in the init_nodeacl and drop_nodeacl routines. Additionally this now respects the get_default_queue_depth method in this code path as well. Signed-off-by: Christoph Hellwig <> Signed-off-by: Nicholas Bellinger <>
2015-05-30target: make the tpg_get_default_depth method optionalChristoph Hellwig
All fabric drivers except for iSCSI always return 1, so implement that as default behavior. Signed-off-by: Christoph Hellwig <> Signed-off-by: Nicholas Bellinger <>
2015-05-30target/user: Add support for bidirectional commandsIlias Tsitsimpis
Enable TCMU to handle bidirectional SCSI commands. In such cases, entries in iov[] cover both the Data-In and the Data-Out buffers. The first iov_cnt entries correspond to the Data-Out buffer, while the remaining iov_bidi_cnt entries correspond to the Data-In buffer. Signed-off-by: Ilias Tsitsimpis <> Signed-off-by: Vangelis Koukis <> Reviewed-by: Andy Grover <> Signed-off-by: Nicholas Bellinger <>
2015-05-30target/user: Only support full command pass-throughAndy Grover
After much discussion, give up on only passing a subset of SCSI commands to userspace and pass them all. Based on what pscsi is doing, make sure to set SCF_SCSI_DATA_CDB for I/O ops, and define attributes identical to pscsi. Make hw_block_size configurable via dev param. Remove mention of command filtering from tcmu-design.txt. Signed-off-by: Andy Grover <> Reviewed-by: Ilias Tsitsimpis <> Signed-off-by: Nicholas Bellinger <>
2015-05-30target/user: Update example code for new ABI requirementsAndy Grover
We now require that the userspace handler set a bit if the command is not handled. Update calls to tcmu_hdr_get_op for v2. Signed-off-by: Andy Grover <> Reviewed-by: Ilias Tsitsimpis <> Signed-off-by: Nicholas Bellinger <>
2015-05-02target/user: Disallow full passthrough (pass_level=0)Andy Grover
TCMU requires more work to correctly handle both user handlers that want all SCSI commands (pass_level=0) for a se_device, and also handlers that just want I/O commands and let the others be emulated by the kernel (pass_level=1). Only support the latter for now. For full passthrough, we will need to support a second se_subsystem_api template, due to configfs attributes being different between the two modes. Thus pass_level is extraneous, and we can remove it. The ABI break for TCMU v2 is already applied for this release, so it's best to do this now to avoid another ABI break in the future. Signed-off-by: Andy Grover <> Reviewed-by: Christoph Hellwig <> Signed-off-by: Nicholas Bellinger <>
2015-04-19target: Version 2 of TCMU ABIAndy Grover
The initial version of TCMU (in 3.18) does not properly handle bidirectional SCSI commands -- those with both an in and out buffer. In looking to fix this it also became clear that TCMU's support for adding new types of entries (opcodes) to the command ring was broken. We need to fix this now, so that future issues can be handled properly by adding new opcodes. We make the most of this ABI break by enabling bidi cmd handling within TCMP_OP_CMD opcode. Add an iov_bidi_cnt field to tcmu_cmd_entry.req. This enables TCMU to describe bidi commands, but further kernel work is needed for full bidi support. Enlarge tcmu_cmd_entry_hdr by 32 bits by pulling in cmd_id and __pad1. Turn __pad1 into two 8 bit flags fields, for kernel-set and userspace-set flags, "kflags" and "uflags" respectively. Update version fields so userspace can tell the interface is changed. Update tcmu-design.txt with details of how new stuff works: - Specify an additional requirement for userspace to set UNKNOWN_OP (bit 0) in hdr.uflags for unknown/unhandled opcodes. - Define how Data-In and Data-Out fields are described in req.iov[] Changed in v2: - Change name of SKIPPED bit to UNKNOWN bit - PAD op does not set the bit any more - Change len_op helper functions to take just len_op, not the whole struct - Change version to 2 in missed spots, and use defines - Add 16 unused bytes to cmd_entry.req, in case additional SAM cmd parameters need to be included - Add iov_dif_cnt field to specify buffers used for DIF info in iov[] - Rearrange fields to naturally align cdb_off - Handle if userspace sets UNKNOWN_OP by indicating failure of the cmd - Wrap some overly long UPDATE_HEAD lines (Add missing req.iov_bidi_cnt + req.iov_dif_cnt zeroing - Ilias) Signed-off-by: Andy Grover <> Reviewed-by: Ilias Tsitsimpis <> Signed-off-by: Nicholas Bellinger <>
2015-04-15target: fix tcm_mod_builder.pyChristoph Hellwig
Fix a misplaced comma I introduced. Signed-off-by: Christoph Hellwig <> Signed-off-by: Nicholas Bellinger <>
2015-04-14target: simplify the target template registration APIChristoph Hellwig
Instead of calling target_fabric_configfs_init() + target_fabric_configfs_register() / target_fabric_configfs_deregister() target_fabric_configfs_free() from every target driver, rewrite the API so that we have simple register/unregister functions that operate on a const operations vector. This patch also fixes a memory leak in several target drivers. Several target drivers namely called target_fabric_configfs_deregister() without calling target_fabric_configfs_free(). A large part of this patch is based on earlier changes from Bart Van Assche <>. (v2: Add a new TF_CIT_SETUP_DRV macro so that the core configfs code can declare attributes as either core only or for drivers) Signed-off-by: Christoph Hellwig <> Signed-off-by: Nicholas Bellinger <>
2015-01-06Documentation/target: Update fabric_ops to latest codeNicholas Bellinger
This patch updates to add/drop a handful of struct target_core_fabric_ops functions to sync up with the latest requirements to function in target_fabric_tf_ops_check(). Signed-off-by: Nicholas Bellinger <>
2014-10-02target: Add documentation on the target userspace pass-through driverAndy Grover
Describes the driver and its interface to make it possible for user programs to back a LIO-exported LUN. Thanks to Richard W. M. Jones for review, and supplementing this doc with the first two paragraphs. Signed-off-by: Andy Grover <> Signed-off-by: Nicholas Bellinger <>
2013-10-16target: Remove TF_CIT_TMPL macroAndy Grover
Remove a lingering macro that just hid a dereference. Reviewed-by: Christoph Hellwig <> Signed-off-by: Andy Grover <> Signed-off-by: Nicholas Bellinger <>
2013-08-20Documentation: replace strict_strtoul() with kstrtoul()Jingoo Han
The usage of strict_strtoul() is not preferred, because strict_strtoul() is obsolete. Thus, kstrtoul() should be used. Signed-off-by: Jingoo Han <> Signed-off-by: Jiri Kosina <>
2012-09-17target: Simplify fabric sense data length handlingRoland Dreier
Every fabric driver has to supply a se_tfo->set_fabric_sense_len() method, just so iSCSI can return an offset of 2. However, every fabric driver is already allocating a sense buffer and passing it into the target core, either via transport_init_se_cmd() or target_submit_cmd(). So instead of having iSCSI pass the start of its sense buffer into the core and then later tell the core to skip the first 2 bytes, it seems easier for iSCSI just to do the offset of 2 when it passes the sense buffer into the core. Then we can drop the se_tfo->set_fabric_sense_len() everywhere, and just add a couple of lines of code to iSCSI to set the sense data length to the beginning of the buffer right before it sends it over the network. (nab: Remove .set_fabric_sense_len usage from tcm_qla2xxx_npiv_ops + change transport_get_sense_buffer to follow v3.6-rc6 code w/o ->set_fabric_sense_len usage) Signed-off-by: Roland Dreier <> Signed-off-by: Nicholas Bellinger <>
2012-09-17target: Remove unused target_core_fabric_ops.get_fabric_sense_len methodRoland Dreier
There are no callers of se_tfo->get_fabric_sense_len(), so we should stop having every fabric driver implement it. Signed-off-by: Roland Dreier <> Signed-off-by: Nicholas Bellinger <>
2012-02-10Documentation: Fix typo in tcm_mod_builder.pyMasanari Iida
Correct spelling "alocate" to "allocate" in Documentation/target/ Signed-off-by: Masanari Iida <> Signed-off-by: Jiri Kosina <>
2011-12-14target: tcm_mod_builder: small fixupsSebastian Andrzej Siewior
This includes: - remove on _ in "__NAMELEN" in $fabric _make_tport - target_fabric_configfs_init() returns an error pointer and not NULL anymore. Consider that. - replace (!(var_name)) with (!var_name). The extra () are not required - remove #ifdef MODULE. If the code is builtin it needs an init function or the code is useless - put exit/clean functions into __exit Signed-off-by: Sebastian Andrzej Siewior <> Signed-off-by: Nicholas Bellinger <>
2011-12-14Documentation/target: Fix build breakageNicholas Bellinger
This patch fixes TFO->release_cmd() and removes legacy pack_lun() usage and new_cmd_failure when generating new TCM fabric skeleton from the script. Reported-by: Stefan Bergstrand <> Signed-off-by: Nicholas Bellinger <>
2011-12-14target: header reshuffle, part2Christoph Hellwig
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 <>
2011-03-23[SCSI] Fix generated *_drop_nodeacl() handlerFubo Chen
This patch adds the missing core_tpg_del_initiator_node_acl() call required by fabric modules for struct se_node_acl->acl_group context shutdown via target_core_fabric_configfs.c:target_fabric_nacl_base_release() -> struct target_core_fabric_ops->fabric_drop_nodeacl() for generated $FABRIC_MOD_configfs.c skeleton code. Signed-off-by: Fubo Chen <> Signed-off-by: Nicholas A. Bellinger <> Signed-off-by: James Bottomley <>
2011-03-23[SCSI] target: generated Makefile cleanupsNicholas Bellinger
This patch converts the generation script to create a new drivers/target/$TCM_FABRIC_MOD/Makefile and update drivers/target/Makefile, instead of creating+updating a 'Kbuild' filename. It also removes the remaining EXTRA_CFLAGS includes from tcm_mod_build_kbuild(), and converts fabric module generated .c code to us ""-style includes for $FABRIC_MOD_[base,fabric].h Reported-by: Christoph Hellwig <> Signed-off-by: Nicholas A. Bellinger <> Signed-off-by: James Bottomley <>
2011-01-14[SCSI] target: Add LIO target core v4.0.0-rc6Nicholas Bellinger
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 <> Signed-off-by: James Bottomley <>