scsi: simplify scsi_free_sgtable()

Just pass in the command, no point in passing in the scatterlist
and scatterlist pool index seperately.
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

drivers/scsi/scsi_lib.c

@@ -741,13 +741,14 @@ struct scatterlist *scsi_alloc_sgtable(struct scsi_cmnd *cmd, gfp_t gfp_mask)
 
 EXPORT_SYMBOL(scsi_alloc_sgtable);
 
-void scsi_free_sgtable(struct scatterlist *sgl, int index)
+void scsi_free_sgtable(struct scsi_cmnd *cmd)
 {
+	struct scatterlist *sgl = cmd->request_buffer;
 	struct scsi_host_sg_pool *sgp;
 
-	BUG_ON(index >= SG_MEMPOOL_NR);
+	BUG_ON(cmd->sglist_len >= SG_MEMPOOL_NR);
 
-	sgp = scsi_sg_pools + index;
+	sgp = scsi_sg_pools + cmd->sglist_len;
 	mempool_free(sgl, sgp->pool);
 }
 
@@ -773,7 +774,7 @@ EXPORT_SYMBOL(scsi_free_sgtable);
 static void scsi_release_buffers(struct scsi_cmnd *cmd)
 {
 	if (cmd->use_sg)
-		scsi_free_sgtable(cmd->request_buffer, cmd->sglist_len);
+		scsi_free_sgtable(cmd);
 
 	/*
 	 * Zero these out.  They now point to freed memory, and it is

drivers/scsi/scsi_tgt_lib.c

@@ -332,7 +332,7 @@ static void scsi_tgt_cmd_done(struct scsi_cmnd *cmd)
 	scsi_tgt_uspace_send_status(cmd, tcmd->itn_id, tcmd->tag);
 
 	if (cmd->request_buffer)
-		scsi_free_sgtable(cmd->request_buffer, cmd->sglist_len);
+		scsi_free_sgtable(cmd);
 
 	queue_work(scsi_tgtd, &tcmd->work);
 }
@@ -373,7 +373,7 @@ static int scsi_tgt_init_cmd(struct scsi_cmnd *cmd, gfp_t gfp_mask)
 	}
 
 	eprintk("cmd %p cnt %d\n", cmd, cmd->use_sg);
-	scsi_free_sgtable(cmd->request_buffer, cmd->sglist_len);
+	scsi_free_sgtable(cmd);
 	return -EINVAL;
 }
 

include/scsi/scsi_cmnd.h

@@ -129,7 +129,7 @@ extern void *scsi_kmap_atomic_sg(struct scatterlist *sg, int sg_count,
 extern void scsi_kunmap_atomic_sg(void *virt);
 
 extern struct scatterlist *scsi_alloc_sgtable(struct scsi_cmnd *, gfp_t);
-extern void scsi_free_sgtable(struct scatterlist *, int);
+extern void scsi_free_sgtable(struct scsi_cmnd *);
 
 extern int scsi_dma_map(struct scsi_cmnd *cmd);
 extern void scsi_dma_unmap(struct scsi_cmnd *cmd);