1 files changed, 143 insertions, 27 deletions

diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index d8e49d7..84747cc 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -3,7 +3,7 @@
  *
  * This file contains the Generic Target Engine Core.
  *
- * (c) Copyright 2002-2012 RisingTide Systems LLC.
+ * (c) Copyright 2002-2013 Datera, Inc.
  *
  * Nicholas A. Bellinger <nab@kernel.org>
  *
@@ -67,7 +67,6 @@ struct kmem_cache *t10_alua_tg_pt_gp_mem_cache;
 static void transport_complete_task_attr(struct se_cmd *cmd);
 static void transport_handle_queue_full(struct se_cmd *cmd,
 		struct se_device *dev);
-static int transport_generic_get_mem(struct se_cmd *cmd);
 static int transport_put_cmd(struct se_cmd *cmd);
 static void target_complete_ok_work(struct work_struct *work);
 
@@ -232,6 +231,50 @@ struct se_session *transport_init_session(void)
 }
 EXPORT_SYMBOL(transport_init_session);
 
+int transport_alloc_session_tags(struct se_session *se_sess,
+			         unsigned int tag_num, unsigned int tag_size)
+{
+	int rc;
+
+	se_sess->sess_cmd_map = kzalloc(tag_num * tag_size, GFP_KERNEL);
+	if (!se_sess->sess_cmd_map) {
+		pr_err("Unable to allocate se_sess->sess_cmd_map\n");
+		return -ENOMEM;
+	}
+
+	rc = percpu_ida_init(&se_sess->sess_tag_pool, tag_num);
+	if (rc < 0) {
+		pr_err("Unable to init se_sess->sess_tag_pool,"
+			" tag_num: %u\n", tag_num);
+		kfree(se_sess->sess_cmd_map);
+		se_sess->sess_cmd_map = NULL;
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(transport_alloc_session_tags);
+
+struct se_session *transport_init_session_tags(unsigned int tag_num,
+					       unsigned int tag_size)
+{
+	struct se_session *se_sess;
+	int rc;
+
+	se_sess = transport_init_session();
+	if (IS_ERR(se_sess))
+		return se_sess;
+
+	rc = transport_alloc_session_tags(se_sess, tag_num, tag_size);
+	if (rc < 0) {
+		transport_free_session(se_sess);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	return se_sess;
+}
+EXPORT_SYMBOL(transport_init_session_tags);
+
 /*
  * Called with spin_lock_irqsave(&struct se_portal_group->session_lock called.
  */
@@ -367,6 +410,10 @@ EXPORT_SYMBOL(transport_deregister_session_configfs);
 
 void transport_free_session(struct se_session *se_sess)
 {
+	if (se_sess->sess_cmd_map) {
+		percpu_ida_destroy(&se_sess->sess_tag_pool);
+		kfree(se_sess->sess_cmd_map);
+	}
 	kmem_cache_free(se_sess_cache, se_sess);
 }
 EXPORT_SYMBOL(transport_free_session);
@@ -1206,7 +1253,7 @@ int transport_handle_cdb_direct(
 }
 EXPORT_SYMBOL(transport_handle_cdb_direct);
 
-static sense_reason_t
+sense_reason_t
 transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *sgl,
 		u32 sgl_count, struct scatterlist *sgl_bidi, u32 sgl_bidi_count)
 {
@@ -1512,6 +1559,13 @@ void transport_generic_request_failure(struct se_cmd *cmd,
 	 * For SAM Task Attribute emulation for failed struct se_cmd
 	 */
 	transport_complete_task_attr(cmd);
+	/*
+	 * Handle special case for COMPARE_AND_WRITE failure, where the
+	 * callback is expected to drop the per device ->caw_mutex.
+	 */
+	if ((cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE) &&
+	     cmd->transport_complete_callback)
+		cmd->transport_complete_callback(cmd);
 
 	switch (sense_reason) {
 	case TCM_NON_EXISTENT_LUN:
@@ -1579,7 +1633,7 @@ queue_full:
 }
 EXPORT_SYMBOL(transport_generic_request_failure);
 
-static void __target_execute_cmd(struct se_cmd *cmd)
+void __target_execute_cmd(struct se_cmd *cmd)
 {
 	sense_reason_t ret;
 
@@ -1784,7 +1838,7 @@ static void transport_complete_qf(struct se_cmd *cmd)
 		ret = cmd->se_tfo->queue_data_in(cmd);
 		break;
 	case DMA_TO_DEVICE:
-		if (cmd->t_bidi_data_sg) {
+		if (cmd->se_cmd_flags & SCF_BIDI) {
 			ret = cmd->se_tfo->queue_data_in(cmd);
 			if (ret < 0)
 				break;
@@ -1856,10 +1910,25 @@ static void target_complete_ok_work(struct work_struct *work)
 	}
 	/*
 	 * Check for a callback, used by amongst other things
-	 * XDWRITE_READ_10 emulation.
+	 * XDWRITE_READ_10 and COMPARE_AND_WRITE emulation.
 	 */
-	if (cmd->transport_complete_callback)
-		cmd->transport_complete_callback(cmd);
+	if (cmd->transport_complete_callback) {
+		sense_reason_t rc;
+
+		rc = cmd->transport_complete_callback(cmd);
+		if (!rc && !(cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE_POST)) {
+			return;
+		} else if (rc) {
+			ret = transport_send_check_condition_and_sense(cmd,
+						rc, 0);
+			if (ret == -EAGAIN || ret == -ENOMEM)
+				goto queue_full;
+
+			transport_lun_remove_cmd(cmd);
+			transport_cmd_check_stop_to_fabric(cmd);
+			return;
+		}
+	}
 
 	switch (cmd->data_direction) {
 	case DMA_FROM_DEVICE:
@@ -1885,7 +1954,7 @@ static void target_complete_ok_work(struct work_struct *work)
 		/*
 		 * Check if we need to send READ payload for BIDI-COMMAND
 		 */
-		if (cmd->t_bidi_data_sg) {
+		if (cmd->se_cmd_flags & SCF_BIDI) {
 			spin_lock(&cmd->se_lun->lun_sep_lock);
 			if (cmd->se_lun->lun_sep) {
 				cmd->se_lun->lun_sep->sep_stats.tx_data_octets +=
@@ -1930,10 +1999,29 @@ static inline void transport_free_sgl(struct scatterlist *sgl, int nents)
 	kfree(sgl);
 }
 
+static inline void transport_reset_sgl_orig(struct se_cmd *cmd)
+{
+	/*
+	 * Check for saved t_data_sg that may be used for COMPARE_AND_WRITE
+	 * emulation, and free + reset pointers if necessary..
+	 */
+	if (!cmd->t_data_sg_orig)
+		return;
+
+	kfree(cmd->t_data_sg);
+	cmd->t_data_sg = cmd->t_data_sg_orig;
+	cmd->t_data_sg_orig = NULL;
+	cmd->t_data_nents = cmd->t_data_nents_orig;
+	cmd->t_data_nents_orig = 0;
+}
+
 static inline void transport_free_pages(struct se_cmd *cmd)
 {
-	if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC)
+	if (cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
+		transport_reset_sgl_orig(cmd);
 		return;
+	}
+	transport_reset_sgl_orig(cmd);
 
 	transport_free_sgl(cmd->t_data_sg, cmd->t_data_nents);
 	cmd->t_data_sg = NULL;
@@ -2029,24 +2117,22 @@ void transport_kunmap_data_sg(struct se_cmd *cmd)
 }
 EXPORT_SYMBOL(transport_kunmap_data_sg);
 
-static int
-transport_generic_get_mem(struct se_cmd *cmd)
+int
+target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, u32 length,
+		 bool zero_page)
 {
-	u32 length = cmd->data_length;
-	unsigned int nents;
+	struct scatterlist *sg;
 	struct page *page;
-	gfp_t zero_flag;
+	gfp_t zero_flag = (zero_page) ? __GFP_ZERO : 0;
+	unsigned int nent;
 	int i = 0;
 
-	nents = DIV_ROUND_UP(length, PAGE_SIZE);
-	cmd->t_data_sg = kmalloc(sizeof(struct scatterlist) * nents, GFP_KERNEL);
-	if (!cmd->t_data_sg)
+	nent = DIV_ROUND_UP(length, PAGE_SIZE);
+	sg = kmalloc(sizeof(struct scatterlist) * nent, GFP_KERNEL);
+	if (!sg)
 		return -ENOMEM;
 
-	cmd->t_data_nents = nents;
-	sg_init_table(cmd->t_data_sg, nents);
-
-	zero_flag = cmd->se_cmd_flags & SCF_SCSI_DATA_CDB ? 0 : __GFP_ZERO;
+	sg_init_table(sg, nent);
 
 	while (length) {
 		u32 page_len = min_t(u32, length, PAGE_SIZE);
@@ -2054,19 +2140,20 @@ transport_generic_get_mem(struct se_cmd *cmd)
 		if (!page)
 			goto out;
 
-		sg_set_page(&cmd->t_data_sg[i], page, page_len, 0);
+		sg_set_page(&sg[i], page, page_len, 0);
 		length -= page_len;
 		i++;
 	}
+	*sgl = sg;
+	*nents = nent;
 	return 0;
 
 out:
 	while (i > 0) {
 		i--;
-		__free_page(sg_page(&cmd->t_data_sg[i]));
+		__free_page(sg_page(&sg[i]));
 	}
-	kfree(cmd->t_data_sg);
-	cmd->t_data_sg = NULL;
+	kfree(sg);
 	return -ENOMEM;
 }
 
@@ -2087,7 +2174,27 @@ transport_generic_new_cmd(struct se_cmd *cmd)
 	 */
 	if (!(cmd->se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) &&
 	    cmd->data_length) {
-		ret = transport_generic_get_mem(cmd);
+		bool zero_flag = !(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB);
+
+		if ((cmd->se_cmd_flags & SCF_BIDI) ||
+		    (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)) {
+			u32 bidi_length;
+
+			if (cmd->se_cmd_flags & SCF_COMPARE_AND_WRITE)
+				bidi_length = cmd->t_task_nolb *
+					      cmd->se_dev->dev_attrib.block_size;
+			else
+				bidi_length = cmd->data_length;
+
+			ret = target_alloc_sgl(&cmd->t_bidi_data_sg,
+					       &cmd->t_bidi_data_nents,
+					       bidi_length, zero_flag);
+			if (ret < 0)
+				return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+		}
+
+		ret = target_alloc_sgl(&cmd->t_data_sg, &cmd->t_data_nents,
+				       cmd->data_length, zero_flag);
 		if (ret < 0)
 			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
 	}
@@ -2740,6 +2847,15 @@ transport_send_check_condition_and_sense(struct se_cmd *cmd,
 		buffer[SPC_ASC_KEY_OFFSET] = asc;
 		buffer[SPC_ASCQ_KEY_OFFSET] = ascq;
 		break;
+	case TCM_MISCOMPARE_VERIFY:
+		/* CURRENT ERROR */
+		buffer[0] = 0x70;
+		buffer[SPC_ADD_SENSE_LEN_OFFSET] = 10;
+		buffer[SPC_SENSE_KEY_OFFSET] = MISCOMPARE;
+		/* MISCOMPARE DURING VERIFY OPERATION */
+		buffer[SPC_ASC_KEY_OFFSET] = 0x1d;
+		buffer[SPC_ASCQ_KEY_OFFSET] = 0x00;
+		break;
 	case TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE:
 	default:
 		/* CURRENT ERROR */