target: Updates from AGrover and HCH (round 3)

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>

2 files changed, 14 insertions, 21 deletions

diff --git a/drivers/target/tcm_fc/tfc_cmd.c b/drivers/target/tcm_fc/tfc_cmd.c
index 6d9553bbba3..910306ce48d 100644
--- a/drivers/target/tcm_fc/tfc_cmd.c
+++ b/drivers/target/tcm_fc/tfc_cmd.c
@@ -60,7 +60,6 @@ void ft_dump_cmd(struct ft_cmd *cmd, const char *caller)
 	struct fc_seq *sp;
 	struct se_cmd *se_cmd;
 	struct se_mem *mem;
-	struct se_transport_task *task;
 
 	if (!(ft_debug_logging & FT_DEBUG_IO))
 		return;
@@ -72,12 +71,11 @@ void ft_dump_cmd(struct ft_cmd *cmd, const char *caller)
 		caller, cmd, cmd->cdb);
 	printk(KERN_INFO "%s: cmd %p lun %d\n", caller, cmd, cmd->lun);
 
-	task = &se_cmd->t_task;
-	printk(KERN_INFO "%s: cmd %p task %p se_num %u buf %p len %u se_cmd_flags <0x%x>\n",
-	       caller, cmd, task, task->t_tasks_se_num,
-	       task->t_task_buf, se_cmd->data_length, se_cmd->se_cmd_flags);
+	printk(KERN_INFO "%s: cmd %p se_num %u buf %p len %u se_cmd_flags <0x%x>\n",
+	       caller, cmd, se_cmd->t_tasks_se_num,
+	       se_cmd->t_task_buf, se_cmd->data_length, se_cmd->se_cmd_flags);
 
-	list_for_each_entry(mem, &task->t_mem_list, se_list)
+	list_for_each_entry(mem, &se_cmd->t_mem_list, se_list)
 		printk(KERN_INFO "%s: cmd %p mem %p page %p "
 		       "len 0x%x off 0x%x\n",
 		       caller, cmd, mem,
@@ -262,9 +260,9 @@ int ft_write_pending(struct se_cmd *se_cmd)
 				 * TCM/LIO target
 				 */
 				transport_do_task_sg_chain(se_cmd);
-				cmd->sg = se_cmd->t_task.t_tasks_sg_chained;
+				cmd->sg = se_cmd->t_tasks_sg_chained;
 				cmd->sg_cnt =
-					se_cmd->t_task.t_tasks_sg_chained_no;
+					se_cmd->t_tasks_sg_chained_no;
 			}
 			if (cmd->sg && lport->tt.ddp_setup(lport, ep->xid,
 						    cmd->sg, cmd->sg_cnt))
diff --git a/drivers/target/tcm_fc/tfc_io.c b/drivers/target/tcm_fc/tfc_io.c
index f18af6e99b8..8560182f0da 100644
--- a/drivers/target/tcm_fc/tfc_io.c
+++ b/drivers/target/tcm_fc/tfc_io.c
@@ -65,7 +65,6 @@
 int ft_queue_data_in(struct se_cmd *se_cmd)
 {
 	struct ft_cmd *cmd = container_of(se_cmd, struct ft_cmd, se_cmd);
-	struct se_transport_task *task;
 	struct fc_frame *fp = NULL;
 	struct fc_exch *ep;
 	struct fc_lport *lport;
@@ -90,14 +89,13 @@ int ft_queue_data_in(struct se_cmd *se_cmd)
 	lport = ep->lp;
 	cmd->seq = lport->tt.seq_start_next(cmd->seq);
 
-	task = &se_cmd->t_task;
 	remaining = se_cmd->data_length;
 
 	/*
 	 * Setup to use first mem list entry if any.
 	 */
-	if (task->t_tasks_se_num) {
-		mem = list_first_entry(&task->t_mem_list,
+	if (se_cmd->t_tasks_se_num) {
+		mem = list_first_entry(&se_cmd->t_mem_list,
 			 struct se_mem, se_list);
 		mem_len = mem->se_len;
 		mem_off = mem->se_off;
@@ -148,8 +146,8 @@ int ft_queue_data_in(struct se_cmd *se_cmd)
 
 		if (use_sg) {
 			if (!mem) {
-				BUG_ON(!task->t_task_buf);
-				page_addr = task->t_task_buf + mem_off;
+				BUG_ON(!se_cmd->t_task_buf);
+				page_addr = se_cmd->t_task_buf + mem_off;
 				/*
 				 * In this case, offset is 'offset_in_page' of
 				 * (t_task_buf + mem_off) instead of 'mem_off'.
@@ -180,7 +178,7 @@ int ft_queue_data_in(struct se_cmd *se_cmd)
 			kunmap_atomic(page_addr, KM_SOFTIRQ0);
 			to += tlen;
 		} else {
-			from = task->t_task_buf + mem_off;
+			from = se_cmd->t_task_buf + mem_off;
 			memcpy(to, from, tlen);
 			to += tlen;
 		}
@@ -220,7 +218,6 @@ void ft_recv_write_data(struct ft_cmd *cmd, struct fc_frame *fp)
 	struct fc_seq *seq = cmd->seq;
 	struct fc_exch *ep;
 	struct fc_lport *lport;
-	struct se_transport_task *task;
 	struct fc_frame_header *fh;
 	struct se_mem *mem;
 	u32 mem_off;
@@ -235,8 +232,6 @@ void ft_recv_write_data(struct ft_cmd *cmd, struct fc_frame *fp)
 	u32 f_ctl;
 	void *buf;
 
-	task = &se_cmd->t_task;
-
 	fh = fc_frame_header_get(fp);
 	if (!(ntoh24(fh->fh_f_ctl) & FC_FC_REL_OFF))
 		goto drop;
@@ -312,8 +307,8 @@ void ft_recv_write_data(struct ft_cmd *cmd, struct fc_frame *fp)
 	/*
 	 * Setup to use first mem list entry if any.
 	 */
-	if (task->t_tasks_se_num) {
-		mem = list_first_entry(&task->t_mem_list,
+	if (se_cmd->t_tasks_se_num) {
+		mem = list_first_entry(&se_cmd->t_mem_list,
 				       struct se_mem, se_list);
 		mem_len = mem->se_len;
 		mem_off = mem->se_off;
@@ -355,7 +350,7 @@ void ft_recv_write_data(struct ft_cmd *cmd, struct fc_frame *fp)
 			memcpy(to, from, tlen);
 			kunmap_atomic(page_addr, KM_SOFTIRQ0);
 		} else {
-			to = task->t_task_buf + mem_off;
+			to = se_cmd->t_task_buf + mem_off;
 			memcpy(to, from, tlen);
 		}
 		from += tlen;