Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/…

…git/nab/target-pending

Pull SCSI target updates from Nicholas Bellinger:
 "Lots of activity in target land the last months.

  The highlights include:

   - Convert fabric drivers tree-wide to target_register_template() (hch
     + bart)

   - iser-target hardening fixes + v1.0 improvements (sagi)

   - Convert iscsi_thread_set usage to kthread.h + kill
     iscsi_target_tq.c (sagi + nab)

   - Add support for T10-PI WRITE_STRIP + READ_INSERT operation (mkp +
     sagi + nab)

   - DIF fixes for CONFIG_DEBUG_SG=y + UNMAP file emulation (akinobu +
     sagi + mkp)

   - Extended TCMU ABI v2 for future BIDI + DIF support (andy + ilias)

   - Fix COMPARE_AND_WRITE handling for NO_ALLLOC drivers (hch + nab)

  Thanks to everyone who contributed this round with new features,
  bug-reports, fixes, cleanups and improvements.

  Looking forward, it's currently shaping up to be a busy v4.2 as well"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (69 commits)
  target: Put TCMU under a new config option
  target: Version 2 of TCMU ABI
  target: fix tcm_mod_builder.py
  target/file: Fix UNMAP with DIF protection support
  target/file: Fix SG table for prot_buf initialization
  target/file: Fix BUG() when CONFIG_DEBUG_SG=y and DIF protection enabled
  target: Make core_tmr_abort_task() skip TMFs
  target/sbc: Update sbc_dif_generate pr_debug output
  target/sbc: Make internal DIF emulation honor ->prot_checks
  target/sbc: Return INVALID_CDB_FIELD if DIF + sess_prot_type disabled
  target: Ensure sess_prot_type is saved across session restart
  target/rd: Don't pass incomplete scatterlist entries to sbc_dif_verify_*
  target: Remove the unused flag SCF_ACK_KREF
  target: Fix two sparse warnings
  target: Fix COMPARE_AND_WRITE with SG_TO_MEM_NOALLOC handling
  target: simplify the target template registration API
  target: simplify target_xcopy_init_pt_lun
  target: remove the unused SCF_CMD_XCOPY_PASSTHROUGH flag
  target/rd: reduce code duplication in rd_execute_rw()
  tcm_loop: fixup tpgt string to integer conversion
  ...

Documentation/target/tcm_mod_builder.py

@@ -237,8 +237,7 @@ def tcm_mod_build_configfs(proto_ident, fabric_mod_dir_var, fabric_mod_name):
 	buf += "#include \"" + fabric_mod_name + "_base.h\"\n"
 	buf += "#include \"" + fabric_mod_name + "_fabric.h\"\n\n"
 
-	buf += "/* Local pointer to allocated TCM configfs fabric module */\n"
-	buf += "struct target_fabric_configfs *" + fabric_mod_name + "_fabric_configfs;\n\n"
+	buf += "static const struct target_core_fabric_ops " + fabric_mod_name + "_ops;\n\n"
 
 	buf += "static struct se_node_acl *" + fabric_mod_name + "_make_nodeacl(\n"
 	buf += "	struct se_portal_group *se_tpg,\n"
@@ -309,8 +308,8 @@ def tcm_mod_build_configfs(proto_ident, fabric_mod_dir_var, fabric_mod_name):
 	buf += "	}\n"
 	buf += "	tpg->" + fabric_mod_port + " = " + fabric_mod_port + ";\n"
 	buf += "	tpg->" + fabric_mod_port + "_tpgt = tpgt;\n\n"
-	buf += "	ret = core_tpg_register(&" + fabric_mod_name + "_fabric_configfs->tf_ops, wwn,\n"
-	buf += "				&tpg->se_tpg, (void *)tpg,\n"
+	buf += "	ret = core_tpg_register(&" + fabric_mod_name + "_ops, wwn,\n"
+	buf += "				&tpg->se_tpg, tpg,\n"
 	buf += "				TRANSPORT_TPG_TYPE_NORMAL);\n"
 	buf += "	if (ret < 0) {\n"
 	buf += "		kfree(tpg);\n"
@@ -370,7 +369,10 @@ def tcm_mod_build_configfs(proto_ident, fabric_mod_dir_var, fabric_mod_name):
 	buf += "	NULL,\n"
 	buf += "};\n\n"
 
-	buf += "static struct target_core_fabric_ops " + fabric_mod_name + "_ops = {\n"
+	buf += "static const struct target_core_fabric_ops " + fabric_mod_name + "_ops = {\n"
+	buf += "	.module				= THIS_MODULE,\n"
+	buf += "	.name				= " + fabric_mod_name + ",\n"
+	buf += "	.get_fabric_proto_ident		= " + fabric_mod_name + "_get_fabric_proto_ident,\n"
 	buf += "	.get_fabric_name		= " + fabric_mod_name + "_get_fabric_name,\n"
 	buf += "	.get_fabric_proto_ident		= " + fabric_mod_name + "_get_fabric_proto_ident,\n"
 	buf += "	.tpg_get_wwn			= " + fabric_mod_name + "_get_fabric_wwn,\n"
@@ -413,75 +415,18 @@ def tcm_mod_build_configfs(proto_ident, fabric_mod_dir_var, fabric_mod_name):
 	buf += "	.fabric_drop_np			= NULL,\n"
 	buf += "	.fabric_make_nodeacl		= " + fabric_mod_name + "_make_nodeacl,\n"
 	buf += "	.fabric_drop_nodeacl		= " + fabric_mod_name + "_drop_nodeacl,\n"
-	buf += "};\n\n"
-
-	buf += "static int " + fabric_mod_name + "_register_configfs(void)\n"
-	buf += "{\n"
-	buf += "	struct target_fabric_configfs *fabric;\n"
-	buf += "	int ret;\n\n"
-	buf += "	printk(KERN_INFO \"" + fabric_mod_name.upper() + " fabric module %s on %s/%s\"\n"
-	buf += "		\" on \"UTS_RELEASE\"\\n\"," + fabric_mod_name.upper() + "_VERSION, utsname()->sysname,\n"
-	buf += "		utsname()->machine);\n"
-	buf += "	/*\n"
-	buf += "	 * Register the top level struct config_item_type with TCM core\n"
-	buf += "	 */\n"
-	buf += "	fabric = target_fabric_configfs_init(THIS_MODULE, \"" + fabric_mod_name + "\");\n"
-	buf += "	if (IS_ERR(fabric)) {\n"
-	buf += "		printk(KERN_ERR \"target_fabric_configfs_init() failed\\n\");\n"
-	buf += "		return PTR_ERR(fabric);\n"
-	buf += "	}\n"
-	buf += "	/*\n"
-	buf += "	 * Setup fabric->tf_ops from our local " + fabric_mod_name + "_ops\n"
-	buf += "	 */\n"
-	buf += "	fabric->tf_ops = " + fabric_mod_name + "_ops;\n"
-	buf += "	/*\n"
-	buf += "	 * Setup default attribute lists for various fabric->tf_cit_tmpl\n"
-	buf += "	 */\n"
-	buf += "	fabric->tf_cit_tmpl.tfc_wwn_cit.ct_attrs = " + fabric_mod_name + "_wwn_attrs;\n"
-	buf += "	fabric->tf_cit_tmpl.tfc_tpg_base_cit.ct_attrs = NULL;\n"
-	buf += "	fabric->tf_cit_tmpl.tfc_tpg_attrib_cit.ct_attrs = NULL;\n"
-	buf += "	fabric->tf_cit_tmpl.tfc_tpg_param_cit.ct_attrs = NULL;\n"
-	buf += "	fabric->tf_cit_tmpl.tfc_tpg_np_base_cit.ct_attrs = NULL;\n"
-	buf += "	fabric->tf_cit_tmpl.tfc_tpg_nacl_base_cit.ct_attrs = NULL;\n"
-	buf += "	fabric->tf_cit_tmpl.tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;\n"
-	buf += "	fabric->tf_cit_tmpl.tfc_tpg_nacl_auth_cit.ct_attrs = NULL;\n"
-	buf += "	fabric->tf_cit_tmpl.tfc_tpg_nacl_param_cit.ct_attrs = NULL;\n"
-	buf += "	/*\n"
-	buf += "	 * Register the fabric for use within TCM\n"
-	buf += "	 */\n"
-	buf += "	ret = target_fabric_configfs_register(fabric);\n"
-	buf += "	if (ret < 0) {\n"
-	buf += "		printk(KERN_ERR \"target_fabric_configfs_register() failed\"\n"
-	buf += "				\" for " + fabric_mod_name.upper() + "\\n\");\n"
-	buf += "		return ret;\n"
-	buf += "	}\n"
-	buf += "	/*\n"
-	buf += "	 * Setup our local pointer to *fabric\n"
-	buf += "	 */\n"
-	buf += "	" + fabric_mod_name + "_fabric_configfs = fabric;\n"
-	buf += "	printk(KERN_INFO \"" +  fabric_mod_name.upper() + "[0] - Set fabric -> " + fabric_mod_name + "_fabric_configfs\\n\");\n"
-	buf += "	return 0;\n"
-	buf += "};\n\n"
-	buf += "static void __exit " + fabric_mod_name + "_deregister_configfs(void)\n"
-	buf += "{\n"
-	buf += "	if (!" + fabric_mod_name + "_fabric_configfs)\n"
-	buf += "		return;\n\n"
-	buf += "	target_fabric_configfs_deregister(" + fabric_mod_name + "_fabric_configfs);\n"
-	buf += "	" + fabric_mod_name + "_fabric_configfs = NULL;\n"
-	buf += "	printk(KERN_INFO \"" +  fabric_mod_name.upper() + "[0] - Cleared " + fabric_mod_name + "_fabric_configfs\\n\");\n"
+	buf += "\n"
+	buf += "	.tfc_wwn_attrs			= " + fabric_mod_name + "_wwn_attrs;\n"
 	buf += "};\n\n"
 
 	buf += "static int __init " + fabric_mod_name + "_init(void)\n"
 	buf += "{\n"
-	buf += "	int ret;\n\n"
-	buf += "	ret = " + fabric_mod_name + "_register_configfs();\n"
-	buf += "	if (ret < 0)\n"
-	buf += "		return ret;\n\n"
-	buf += "	return 0;\n"
+	buf += "	return target_register_template(" + fabric_mod_name + "_ops);\n"
 	buf += "};\n\n"
+
 	buf += "static void __exit " + fabric_mod_name + "_exit(void)\n"
 	buf += "{\n"
-	buf += "	" + fabric_mod_name + "_deregister_configfs();\n"
+	buf += "	target_unregister_template(" + fabric_mod_name + "_ops);\n"
 	buf += "};\n\n"
 
 	buf += "MODULE_DESCRIPTION(\"" + fabric_mod_name.upper() + " series fabric driver\");\n"

Documentation/target/tcmu-design.txt

@@ -138,27 +138,40 @@ signals the kernel via a 4-byte write(). When cmd_head equals
 cmd_tail, the ring is empty -- no commands are currently waiting to be
 processed by userspace.
 
-TCMU commands start with a common header containing "len_op", a 32-bit
-value that stores the length, as well as the opcode in the lowest
-unused bits. Currently only two opcodes are defined, TCMU_OP_PAD and
-TCMU_OP_CMD. When userspace encounters a command with PAD opcode, it
-should skip ahead by the bytes in "length". (The kernel inserts PAD
-entries to ensure each CMD entry fits contigously into the circular
-buffer.)
-
-When userspace handles a CMD, it finds the SCSI CDB (Command Data
-Block) via tcmu_cmd_entry.req.cdb_off. This is an offset from the
-start of the overall shared memory region, not the entry. The data
-in/out buffers are accessible via tht req.iov[] array. Note that
-each iov.iov_base is also an offset from the start of the region.
-
-TCMU currently does not support BIDI operations.
+TCMU commands are 8-byte aligned. They start with a common header
+containing "len_op", a 32-bit value that stores the length, as well as
+the opcode in the lowest unused bits. It also contains cmd_id and
+flags fields for setting by the kernel (kflags) and userspace
+(uflags).
+
+Currently only two opcodes are defined, TCMU_OP_CMD and TCMU_OP_PAD.
+
+When the opcode is CMD, the entry in the command ring is a struct
+tcmu_cmd_entry. Userspace finds the SCSI CDB (Command Data Block) via
+tcmu_cmd_entry.req.cdb_off. This is an offset from the start of the
+overall shared memory region, not the entry. The data in/out buffers
+are accessible via tht req.iov[] array. iov_cnt contains the number of
+entries in iov[] needed to describe either the Data-In or Data-Out
+buffers. For bidirectional commands, iov_cnt specifies how many iovec
+entries cover the Data-Out area, and iov_bidi_count specifies how many
+iovec entries immediately after that in iov[] cover the Data-In
+area. Just like other fields, iov.iov_base is an offset from the start
+of the region.
 
 When completing a command, userspace sets rsp.scsi_status, and
 rsp.sense_buffer if necessary. Userspace then increments
 mailbox.cmd_tail by entry.hdr.length (mod cmdr_size) and signals the
 kernel via the UIO method, a 4-byte write to the file descriptor.
 
+When the opcode is PAD, userspace only updates cmd_tail as above --
+it's a no-op. (The kernel inserts PAD entries to ensure each CMD entry
+is contiguous within the command ring.)
+
+More opcodes may be added in the future. If userspace encounters an
+opcode it does not handle, it must set UNKNOWN_OP bit (bit 0) in
+hdr.uflags, update cmd_tail, and proceed with processing additional
+commands, if any.
+
 The Data Area:
 
 This is shared-memory space after the command ring. The organization