Fix handling of MODE SENSE commands in scst_pre_dev_done()

Report the "write protect" flag correctly for read-only devices.

Reported-by: Krzysztof Rusek <rusek@9livesdata.com>


git-svn-id: http://svn.code.sf.net/p/scst/svn/trunk@9043 d57e44dd-8a1f-0410-8b47-8ef2f437770f

scst/include/scst.h

@@ -5106,7 +5106,7 @@ static inline int scst_get_out_buf_count(struct scst_cmd *cmd)
 	return (cmd->out_sg_cnt == 0) ? 1 : cmd->out_sg_cnt;
 }
 
-int scst_get_buf_full(struct scst_cmd *cmd, uint8_t **buf);
+int scst_get_buf_full(struct scst_cmd *cmd, uint8_t **buf, bool always_copy);
 int scst_get_buf_full_sense(struct scst_cmd *cmd, uint8_t **buf);
 void scst_put_buf_full(struct scst_cmd *cmd, uint8_t *buf);
 

scst/src/scst_copy_mgr.c

@@ -2352,7 +2352,7 @@ static void scst_cm_init_inq_finish(struct scst_cmd *cmd)
 		goto out;
 	}
 
-	length = scst_get_buf_full(cmd, &buf);
+	length = scst_get_buf_full(cmd, &buf, false);
 	TRACE_DBG("length %d", length);
 	if (unlikely(length <= 0)) {
 		if (length < 0)

scst/src/scst_lib.c

@@ -5953,7 +5953,7 @@ static void scst_complete_request_sense(struct scst_cmd *req_cmd)
 
 	sBUG_ON(orig_cmd == NULL);
 
-	len = scst_get_buf_full(req_cmd, &buf);
+	len = scst_get_buf_full(req_cmd, &buf, false);
 
 	if (scsi_status_is_good(req_cmd->status) && (len > 0) &&
 	    scst_sense_valid(buf)) {
@@ -9113,12 +9113,13 @@ EXPORT_SYMBOL_GPL(scst_copy_sg);
  * scst_get_buf_full - return linear buffer for command
  * @cmd:	scst command
  * @buf:	pointer on the resulting pointer
+ * @always_copy: copy the data buffer even for commands that read data
  *
  * If the command's buffer >single page, it vmalloc() the needed area
  * and copies the buffer there. Returns length of the buffer or negative
  * error code otherwise.
  */
-int scst_get_buf_full(struct scst_cmd *cmd, uint8_t **buf)
+int scst_get_buf_full(struct scst_cmd *cmd, uint8_t **buf, bool always_copy)
 {
 	int res = 0;
 
@@ -9153,7 +9154,8 @@ int scst_get_buf_full(struct scst_cmd *cmd, uint8_t **buf)
 		}
 		cmd->sg_buff_vmallocated = 1;
 
-		if (scst_cmd_get_data_direction(cmd) == SCST_DATA_WRITE) {
+		if (scst_cmd_get_data_direction(cmd) == SCST_DATA_WRITE ||
+		    always_copy) {
 			uint8_t *buf_ptr;
 
 			buf_ptr = *buf;
@@ -9191,7 +9193,7 @@ int scst_get_buf_full_sense(struct scst_cmd *cmd, uint8_t **buf)
 
 	TRACE_ENTRY();
 
-	res = scst_get_buf_full(cmd, buf);
+	res = scst_get_buf_full(cmd, buf, false);
 	if (unlikely(res < 0)) {
 		PRINT_ERROR("scst_get_buf_full() failed: %d", res);
 		if (res == -ENOMEM)
@@ -12573,7 +12575,7 @@ int scst_block_generic_dev_done(struct scst_cmd *cmd,
 			int buffer_size, sector_size, sh;
 			uint8_t *buffer;
 
-			buffer_size = scst_get_buf_full(cmd, &buffer);
+			buffer_size = scst_get_buf_full(cmd, &buffer, false);
 			sect_sz_off = opcode == READ_CAPACITY ? 4 : 8;
 			if (buffer_size < sect_sz_off + 4) {
 				scst_put_buf_full(cmd, buffer);
@@ -12619,7 +12621,7 @@ int scst_tape_generic_dev_done(struct scst_cmd *cmd,
 	switch (opcode) {
 	case MODE_SENSE:
 	case MODE_SELECT:
-		buffer_size = scst_get_buf_full(cmd, &buffer);
+		buffer_size = scst_get_buf_full(cmd, &buffer, false);
 		if (unlikely(buffer_size <= 0)) {
 			if (buffer_size < 0) {
 				PRINT_ERROR("%s: Unable to get the buffer (%d)",

scst/src/scst_targ.c

@@ -3299,7 +3299,7 @@ next:
 			uint8_t *address;
 			bool err = false;
 
-			length = scst_get_buf_full(cmd, &address);
+			length = scst_get_buf_full(cmd, &address, true);
 			if (length < 0) {
 				PRINT_ERROR("%s", "Unable to get "
 					"MODE_SENSE buffer");

scst/src/scst_tg.c

@@ -1839,7 +1839,7 @@ int scst_tg_set_group_info(struct scst_cmd *cmd)
 
 	TRACE_ENTRY();
 
-	len = scst_get_buf_full(cmd, &buf);
+	len = scst_get_buf_full(cmd, &buf, false);
 	if (len < 0) {
 		PRINT_ERROR("scst_get_buf_full() failed: %d", len);
 		res = len;