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>

drivers/infiniband/ulp/srpt/ib_srpt.c

@@ -1878,8 +1878,8 @@ static void srpt_handle_tsk_mgmt(struct srpt_rdma_ch *ch,
 			TMR_TASK_MGMT_FUNCTION_NOT_SUPPORTED;
 		goto process_tmr;
 	}
-	cmd->se_tmr_req = core_tmr_alloc_req(cmd, NULL, tcm_tmr, GFP_KERNEL);
-	if (!cmd->se_tmr_req) {
+	res = core_tmr_alloc_req(cmd, NULL, tcm_tmr, GFP_KERNEL);
+	if (res < 0) {
 		send_ioctx->cmd.se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
 		send_ioctx->cmd.se_tmr_req->response = TMR_FUNCTION_REJECTED;
 		goto process_tmr;

drivers/target/iscsi/iscsi_target_util.c

@@ -229,6 +229,7 @@ struct iscsi_cmd *iscsit_allocate_se_cmd_for_tmr(
 {
 	struct iscsi_cmd *cmd;
 	struct se_cmd *se_cmd;
+	int rc;
 	u8 tcm_function;
 
 	cmd = iscsit_allocate_cmd(conn, GFP_KERNEL);
@@ -286,10 +287,8 @@ struct iscsi_cmd *iscsit_allocate_se_cmd_for_tmr(
 		goto out;
 	}
 
-	se_cmd->se_tmr_req = core_tmr_alloc_req(se_cmd,
-				cmd->tmr_req, tcm_function,
-				GFP_KERNEL);
-	if (!se_cmd->se_tmr_req)
+	rc = core_tmr_alloc_req(se_cmd, cmd->tmr_req, tcm_function, GFP_KERNEL);
+	if (rc < 0)
 		goto out;
 
 	cmd->tmr_req->se_tmr_req = se_cmd->se_tmr_req;

drivers/target/loopback/tcm_loop.c

@@ -187,7 +187,7 @@ static int tcm_loop_check_stop_free(struct se_cmd *se_cmd)
 	 * pointer.  These will be released directly in tcm_loop_device_reset()
 	 * with transport_generic_free_cmd().
 	 */
-	if (se_cmd->se_tmr_req)
+	if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
 		return 0;
 	/*
 	 * Release the struct se_cmd, which will make a callback to release
@@ -324,7 +324,7 @@ static int tcm_loop_device_reset(struct scsi_cmnd *sc)
 	struct tcm_loop_nexus *tl_nexus;
 	struct tcm_loop_tmr *tl_tmr = NULL;
 	struct tcm_loop_tpg *tl_tpg;
-	int ret = FAILED;
+	int ret = FAILED, rc;
 	/*
 	 * Locate the tcm_loop_hba_t pointer
 	 */
@@ -365,12 +365,9 @@ static int tcm_loop_device_reset(struct scsi_cmnd *sc)
 	transport_init_se_cmd(se_cmd, se_tpg->se_tpg_tfo, se_sess, 0,
 				DMA_NONE, MSG_SIMPLE_TAG,
 				&tl_cmd->tl_sense_buf[0]);
-	/*
-	 * Allocate the LUN_RESET TMR
-	 */
-	se_cmd->se_tmr_req = core_tmr_alloc_req(se_cmd, tl_tmr,
-						TMR_LUN_RESET, GFP_KERNEL);
-	if (IS_ERR(se_cmd->se_tmr_req))
+
+	rc = core_tmr_alloc_req(se_cmd, tl_tmr, TMR_LUN_RESET, GFP_KERNEL);
+	if (rc < 0)
 		goto release;
 	/*
 	 * Locate the underlying TCM struct se_lun from sc->device->lun

drivers/target/target_core_tmr.c

@@ -40,25 +40,28 @@
 #include "target_core_alua.h"
 #include "target_core_pr.h"
 
-struct se_tmr_req *core_tmr_alloc_req(
+int core_tmr_alloc_req(
 	struct se_cmd *se_cmd,
 	void *fabric_tmr_ptr,
 	u8 function,
 	gfp_t gfp_flags)
 {
 	struct se_tmr_req *tmr;
 
-	tmr = kmem_cache_zalloc(se_tmr_req_cache, gfp_flags);
+	tmr = kzalloc(sizeof(struct se_tmr_req), gfp_flags);
 	if (!tmr) {
 		pr_err("Unable to allocate struct se_tmr_req\n");
-		return ERR_PTR(-ENOMEM);
+		return -ENOMEM;
 	}
+
+	se_cmd->se_cmd_flags |= SCF_SCSI_TMR_CDB;
+	se_cmd->se_tmr_req = tmr;
 	tmr->task_cmd = se_cmd;
 	tmr->fabric_tmr_ptr = fabric_tmr_ptr;
 	tmr->function = function;
 	INIT_LIST_HEAD(&tmr->tmr_list);
 
-	return tmr;
+	return 0;
 }
 EXPORT_SYMBOL(core_tmr_alloc_req);
 
@@ -69,15 +72,15 @@ void core_tmr_release_req(
 	unsigned long flags;
 
 	if (!dev) {
-		kmem_cache_free(se_tmr_req_cache, tmr);
+		kfree(tmr);
 		return;
 	}
 
 	spin_lock_irqsave(&dev->se_tmr_lock, flags);
 	list_del(&tmr->tmr_list);
 	spin_unlock_irqrestore(&dev->se_tmr_lock, flags);
 
-	kmem_cache_free(se_tmr_req_cache, tmr);
+	kfree(tmr);
 }
 
 static void core_tmr_handle_tas_abort(

drivers/target/target_core_transport.c

@@ -58,7 +58,6 @@ static int sub_api_initialized;
 
 static struct workqueue_struct *target_completion_wq;
 static struct kmem_cache *se_sess_cache;
-struct kmem_cache *se_tmr_req_cache;
 struct kmem_cache *se_ua_cache;
 struct kmem_cache *t10_pr_reg_cache;
 struct kmem_cache *t10_alua_lu_gp_cache;
@@ -82,21 +81,13 @@ static void target_complete_ok_work(struct work_struct *work);
 
 int init_se_kmem_caches(void)
 {
-	se_tmr_req_cache = kmem_cache_create("se_tmr_cache",
-			sizeof(struct se_tmr_req), __alignof__(struct se_tmr_req),
-			0, NULL);
-	if (!se_tmr_req_cache) {
-		pr_err("kmem_cache_create() for struct se_tmr_req"
-				" failed\n");
-		goto out;
-	}
 	se_sess_cache = kmem_cache_create("se_sess_cache",
 			sizeof(struct se_session), __alignof__(struct se_session),
 			0, NULL);
 	if (!se_sess_cache) {
 		pr_err("kmem_cache_create() for struct se_session"
 				" failed\n");
-		goto out_free_tmr_req_cache;
+		goto out;
 	}
 	se_ua_cache = kmem_cache_create("se_ua_cache",
 			sizeof(struct se_ua), __alignof__(struct se_ua),
@@ -169,16 +160,13 @@ int init_se_kmem_caches(void)
 	kmem_cache_destroy(se_ua_cache);
 out_free_sess_cache:
 	kmem_cache_destroy(se_sess_cache);
-out_free_tmr_req_cache:
-	kmem_cache_destroy(se_tmr_req_cache);
 out:
 	return -ENOMEM;
 }
 
 void release_se_kmem_caches(void)
 {
 	destroy_workqueue(target_completion_wq);
-	kmem_cache_destroy(se_tmr_req_cache);
 	kmem_cache_destroy(se_sess_cache);
 	kmem_cache_destroy(se_ua_cache);
 	kmem_cache_destroy(t10_pr_reg_cache);
@@ -553,7 +541,7 @@ static void transport_lun_remove_cmd(struct se_cmd *cmd)
 
 void transport_cmd_finish_abort(struct se_cmd *cmd, int remove)
 {
-	if (!cmd->se_tmr_req)
+	if (!(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
 		transport_lun_remove_cmd(cmd);
 
 	if (transport_cmd_check_stop_to_fabric(cmd))
@@ -3367,7 +3355,7 @@ static void transport_release_cmd(struct se_cmd *cmd)
 {
 	BUG_ON(!cmd->se_tfo);
 
-	if (cmd->se_tmr_req)
+	if (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)
 		core_tmr_release_req(cmd->se_tmr_req);
 	if (cmd->t_task_cdb != cmd->__t_task_cdb)
 		kfree(cmd->t_task_cdb);
@@ -3956,7 +3944,7 @@ static int transport_generic_write_pending(struct se_cmd *cmd)
 void transport_generic_free_cmd(struct se_cmd *cmd, int wait_for_tasks)
 {
 	if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD)) {
-		if (wait_for_tasks && cmd->se_tmr_req)
+		if (wait_for_tasks && (cmd->se_cmd_flags & SCF_SCSI_TMR_CDB))
 			 transport_wait_for_tasks(cmd);
 
 		transport_release_cmd(cmd);
@@ -4282,15 +4270,17 @@ bool transport_wait_for_tasks(struct se_cmd *cmd)
 	unsigned long flags;
 
 	spin_lock_irqsave(&cmd->t_state_lock, flags);
-	if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) && !(cmd->se_tmr_req)) {
+	if (!(cmd->se_cmd_flags & SCF_SE_LUN_CMD) &&
+	    !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 		return false;
 	}
 	/*
 	 * Only perform a possible wait_for_tasks if SCF_SUPPORTED_SAM_OPCODE
 	 * has been set in transport_set_supported_SAM_opcode().
 	 */
-	if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) && !cmd->se_tmr_req) {
+	if (!(cmd->se_cmd_flags & SCF_SUPPORTED_SAM_OPCODE) &&
+	    !(cmd->se_cmd_flags & SCF_SCSI_TMR_CDB)) {
 		spin_unlock_irqrestore(&cmd->t_state_lock, flags);
 		return false;
 	}

drivers/target/tcm_fc/tfc_cmd.c

@@ -356,6 +356,7 @@ static void ft_send_tm(struct ft_cmd *cmd)
 	struct se_tmr_req *tmr;
 	struct fcp_cmnd *fcp;
 	struct ft_sess *sess;
+	int rc;
 	u8 tm_func;
 
 	transport_init_se_cmd(&cmd->se_cmd, &ft_configfs->tf_ops,
@@ -392,13 +393,12 @@ static void ft_send_tm(struct ft_cmd *cmd)
 	}
 
 	pr_debug("alloc tm cmd fn %d\n", tm_func);
-	tmr = core_tmr_alloc_req(&cmd->se_cmd, cmd, tm_func, GFP_KERNEL);
-	if (!tmr) {
+	rc = core_tmr_alloc_req(&cmd->se_cmd, cmd, tm_func, GFP_KERNEL);
+	if (rc < 0) {
 		pr_debug("alloc failed\n");
 		ft_send_resp_code_and_free(cmd, FCP_TMF_FAILED);
 		return;
 	}
-	cmd->se_cmd.se_tmr_req = tmr;
 
 	switch (fcp->fc_tm_flags) {
 	case FCP_TMF_LUN_RESET:

include/target/target_core_base.h

@@ -169,7 +169,8 @@ enum se_cmd_flags_table {
 	SCF_EMULATED_TASK_SENSE		= 0x00000004,
 	SCF_SCSI_DATA_SG_IO_CDB		= 0x00000008,
 	SCF_SCSI_CONTROL_SG_IO_CDB	= 0x00000010,
-	SCF_SCSI_NON_DATA_CDB		= 0x00000040,
+	SCF_SCSI_NON_DATA_CDB		= 0x00000020,
+	SCF_SCSI_TMR_CDB		= 0x00000040,
 	SCF_SCSI_CDB_EXCEPTION		= 0x00000080,
 	SCF_SCSI_RESERVATION_CONFLICT	= 0x00000100,
 	SCF_FUA				= 0x00000200,
@@ -498,6 +499,24 @@ struct se_task {
 	struct completion	task_stop_comp;
 };
 
+struct se_tmr_req {
+	/* Task Management function to be performed */
+	u8			function;
+	/* Task Management response to send */
+	u8			response;
+	int			call_transport;
+	/* Reference to ITT that Task Mgmt should be performed */
+	u32			ref_task_tag;
+	/* 64-bit encoded SAM LUN from $FABRIC_MOD TMR header */
+	u64			ref_task_lun;
+	void 			*fabric_tmr_ptr;
+	struct se_cmd		*task_cmd;
+	struct se_cmd		*ref_cmd;
+	struct se_device	*tmr_dev;
+	struct se_lun		*tmr_lun;
+	struct list_head	tmr_list;
+};
+
 struct se_cmd {
 	/* SAM response code being sent to initiator */
 	u8			scsi_status;
@@ -586,24 +605,6 @@ struct se_cmd {
 
 };
 
-struct se_tmr_req {
-	/* Task Management function to be performed */
-	u8			function;
-	/* Task Management response to send */
-	u8			response;
-	int			call_transport;
-	/* Reference to ITT that Task Mgmt should be performed */
-	u32			ref_task_tag;
-	/* 64-bit encoded SAM LUN from $FABRIC_MOD TMR header */
-	u64			ref_task_lun;
-	void 			*fabric_tmr_ptr;
-	struct se_cmd		*task_cmd;
-	struct se_cmd		*ref_cmd;
-	struct se_device	*tmr_dev;
-	struct se_lun		*tmr_lun;
-	struct list_head	tmr_list;
-};
-
 struct se_ua {
 	u8			ua_asc;
 	u8			ua_ascq;

include/target/target_core_fabric.h

@@ -139,7 +139,7 @@ void	target_wait_for_sess_cmds(struct se_session *, int);
 
 int	core_alua_check_nonop_delay(struct se_cmd *);
 
-struct se_tmr_req *core_tmr_alloc_req(struct se_cmd *, void *, u8, gfp_t);
+int	core_tmr_alloc_req(struct se_cmd *, void *, u8, gfp_t);
 void	core_tmr_release_req(struct se_tmr_req *);
 int	transport_generic_handle_tmr(struct se_cmd *);
 int	transport_lookup_tmr_lun(struct se_cmd *, u32);