SBC: Add support for WRITESAME10 and a simple test for using writesame10 to unmap blocks from thin provisioned luns

lib/scsi-command.c

@@ -794,6 +794,50 @@ iscsi_synchronizecache10_task(struct iscsi_context *iscsi, int lun, int lba,
 	return task;
 }
 
+
+struct scsi_task *
+iscsi_writesame10_task(struct iscsi_context *iscsi, int lun,
+		       unsigned char *data, uint32_t datalen,
+		       uint32_t lba, uint16_t num_blocks,
+		       int anchor, int unmap, int pbdata, int lbdata,
+		       int wrprotect, int group,
+		       iscsi_command_cb cb, void *private_data)
+{
+	struct scsi_task *task;
+	struct iscsi_data outdata;
+
+	task = scsi_cdb_writesame10(wrprotect, anchor, unmap, pbdata, lbdata, lba, group, num_blocks);
+	if (task == NULL) {
+		iscsi_set_error(iscsi, "Out-of-memory: Failed to create "
+				"writesame10 cdb.");
+		return NULL;
+	}
+
+	if (datalen) {
+		outdata.data = data;
+		outdata.size = datalen;
+		task->expxferlen = datalen;
+
+		if (iscsi_scsi_command_async(iscsi, lun, task, cb, &outdata,
+				       private_data) != 0) {
+			scsi_free_scsi_task(task);
+			return NULL;
+		}
+	} else {
+		task->expxferlen = 0;
+		task->xfer_dir = SCSI_XFER_NONE;
+
+		if (iscsi_scsi_command_async(iscsi, lun, task, cb, NULL,
+				       private_data) != 0) {
+			scsi_free_scsi_task(task);
+			return NULL;
+		}
+	}
+
+	return task;
+}
+
+
 struct scsi_task *
 iscsi_unmap_task(struct iscsi_context *iscsi, int lun, int anchor, int group,
 		 struct unmap_list *list, int list_len,

lib/scsi-lowlevel.c

@@ -789,6 +789,50 @@ scsi_cdb_unmap(int anchor, int group, uint16_t xferlen)
 	return task;
 }
 
+/*
+ * WRITE_SAME10
+ */
+struct scsi_task *
+scsi_cdb_writesame10(int wrprotect, int anchor, int unmap, int pbdata, int lbdata, uint32_t lba, int group, uint16_t num_blocks)
+{
+	struct scsi_task *task;
+
+	task = malloc(sizeof(struct scsi_task));
+	if (task == NULL) {
+		return NULL;
+	}
+
+	memset(task, 0, sizeof(struct scsi_task));
+	task->cdb[0]   = SCSI_OPCODE_WRITE_SAME10;
+
+	if (wrprotect) {
+		task->cdb[1] |= ((wrprotect & 0x7) << 5);
+	}
+	if (anchor) {
+		task->cdb[1] |= 0x10;
+	}
+	if (unmap) {
+		task->cdb[1] |= 0x08;
+	}
+	if (pbdata) {
+		task->cdb[1] |= 0x04;
+	}
+	if (lbdata) {
+		task->cdb[1] |= 0x02;
+	}
+	*(uint32_t *)&task->cdb[2] = htonl(lba);
+	if (group) {
+		task->cdb[6] |= (group & 0x1f);
+	}
+	*(uint16_t *)&task->cdb[7] = htons(num_blocks);
+
+	task->cdb_size = 10;
+	task->xfer_dir = SCSI_XFER_WRITE;
+	task->expxferlen = 512;
+
+	return task;
+}
+
 /*
  * MODESENSE6
  */

lib/sync.c

@@ -361,6 +361,32 @@ iscsi_verify10_sync(struct iscsi_context *iscsi, int lun, unsigned char *data, u
 	return state.task;
 }
 
+struct scsi_task *
+iscsi_writesame10_sync(struct iscsi_context *iscsi, int lun,
+		       unsigned char *data, uint32_t datalen,
+		       uint32_t lba, uint16_t num_blocks,
+		       int anchor, int unmap, int pbdata, int lbdata,
+		       int wrprotect, int group)
+{
+	struct iscsi_sync_state state;
+
+	memset(&state, 0, sizeof(state));
+
+	if (iscsi_writesame10_task(iscsi, lun, data, datalen,
+	   			 lba, num_blocks,
+	   			 anchor, unmap, pbdata, lbdata,
+				 wrprotect, group,
+				 scsi_sync_cb, &state) == NULL) {
+		iscsi_set_error(iscsi,
+				"Failed to send WRITESAME10 command");
+		return NULL;
+	}
+
+	event_loop(iscsi, &state);
+
+	return state.task;
+}
+
 struct scsi_task *
 iscsi_unmap_sync(struct iscsi_context *iscsi, int lun, int anchor, int group,
 		 struct unmap_list *list, int list_len)