target/sbc: Seperate WRITE_SAME based on UNMAP flag in sbc_ops
This patch adds a new sbc_ops->execute_write_same_unmap() caller for use
with WRITE_SAME w/ UNMAP=1, and performs the ->execute_cmd() setup based
this bit within sbc_setup_write_same() code.
Also, makes the changes in sbc_parse_cdb() to handle a sense_reason_t
return from sbc_setup_write_same() on error.
Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c
index b802421..a5a8f46 100644
--- a/drivers/target/target_core_sbc.c
+++ b/drivers/target/target_core_sbc.c
@@ -235,26 +235,30 @@
return ((unsigned long long)__v2) | (unsigned long long)__v1 << 32;
}
-static int sbc_write_same_supported(struct se_device *dev,
- unsigned char *flags)
+static sense_reason_t
+sbc_setup_write_same(struct se_cmd *cmd, unsigned char *flags, struct sbc_ops *ops)
{
if ((flags[0] & 0x04) || (flags[0] & 0x02)) {
pr_err("WRITE_SAME PBDATA and LBDATA"
" bits not supported for Block Discard"
" Emulation\n");
- return -ENOSYS;
+ return TCM_UNSUPPORTED_SCSI_OPCODE;
}
-
/*
- * Currently for the emulated case we only accept
- * tpws with the UNMAP=1 bit set.
+ * Special case for WRITE_SAME w/ UNMAP=1 that ends up getting
+ * translated into block discard requests within backend code.
*/
- if (!(flags[0] & 0x08)) {
- pr_err("WRITE_SAME w/o UNMAP bit not"
- " supported for Block Discard Emulation\n");
- return -ENOSYS;
- }
+ if (flags[0] & 0x08) {
+ if (!ops->execute_write_same_unmap)
+ return TCM_UNSUPPORTED_SCSI_OPCODE;
+ cmd->execute_cmd = ops->execute_write_same_unmap;
+ return 0;
+ }
+ if (!ops->execute_write_same)
+ return TCM_UNSUPPORTED_SCSI_OPCODE;
+
+ cmd->execute_cmd = ops->execute_write_same;
return 0;
}
@@ -418,9 +422,6 @@
cmd->se_cmd_flags |= SCF_FUA;
break;
case WRITE_SAME_32:
- if (!ops->execute_write_same)
- return TCM_UNSUPPORTED_SCSI_OPCODE;
-
sectors = transport_get_sectors_32(cdb);
if (!sectors) {
pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
@@ -431,9 +432,9 @@
size = sbc_get_size(cmd, 1);
cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
- if (sbc_write_same_supported(dev, &cdb[10]) < 0)
- return TCM_UNSUPPORTED_SCSI_OPCODE;
- cmd->execute_cmd = ops->execute_write_same;
+ ret = sbc_setup_write_same(cmd, &cdb[10], ops);
+ if (ret < 0)
+ return ret;
break;
default:
pr_err("VARIABLE_LENGTH_CMD service action"
@@ -495,9 +496,6 @@
cmd->execute_cmd = ops->execute_unmap;
break;
case WRITE_SAME_16:
- if (!ops->execute_write_same)
- return TCM_UNSUPPORTED_SCSI_OPCODE;
-
sectors = transport_get_sectors_16(cdb);
if (!sectors) {
pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
@@ -507,14 +505,11 @@
size = sbc_get_size(cmd, 1);
cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
- if (sbc_write_same_supported(dev, &cdb[1]) < 0)
- return TCM_UNSUPPORTED_SCSI_OPCODE;
- cmd->execute_cmd = ops->execute_write_same;
+ ret = sbc_setup_write_same(cmd, &cdb[1], ops);
+ if (ret < 0)
+ return ret;
break;
case WRITE_SAME:
- if (!ops->execute_write_same)
- return TCM_UNSUPPORTED_SCSI_OPCODE;
-
sectors = transport_get_sectors_10(cdb);
if (!sectors) {
pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
@@ -528,9 +523,9 @@
* Follow sbcr26 with WRITE_SAME (10) and check for the existence
* of byte 1 bit 3 UNMAP instead of original reserved field
*/
- if (sbc_write_same_supported(dev, &cdb[1]) < 0)
- return TCM_UNSUPPORTED_SCSI_OPCODE;
- cmd->execute_cmd = ops->execute_write_same;
+ ret = sbc_setup_write_same(cmd, &cdb[1], ops);
+ if (ret < 0)
+ return ret;
break;
case VERIFY:
size = 0;