target: pass sense_reason as a return value
Pass the sense reason as an explicit return value from the I/O submission
path instead of storing it in struct se_cmd and using negative return
values. This cleans up a lot of the code pathes, and with the sparse
annotations for the new sense_reason_t type allows for much better
error checking.
(nab: Convert spc_emulate_modesense + spc_emulate_modeselect to use
sense_reason_t with Roland's MODE SELECT changes)
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.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 a4eb9c5..3929fa2 100644
--- a/drivers/target/target_core_sbc.c
+++ b/drivers/target/target_core_sbc.c
@@ -37,7 +37,8 @@
#include "target_core_ua.h"
-static int sbc_emulate_readcapacity(struct se_cmd *cmd)
+static sense_reason_t
+sbc_emulate_readcapacity(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
unsigned long long blocks_long = dev->transport->get_blocks(dev);
@@ -60,16 +61,18 @@
buf[7] = dev->dev_attrib.block_size & 0xff;
rbuf = transport_kmap_data_sg(cmd);
- if (rbuf) {
- memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
- transport_kunmap_data_sg(cmd);
- }
+ if (!rbuf)
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+
+ memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
+ transport_kunmap_data_sg(cmd);
target_complete_cmd(cmd, GOOD);
return 0;
}
-static int sbc_emulate_readcapacity_16(struct se_cmd *cmd)
+static sense_reason_t
+sbc_emulate_readcapacity_16(struct se_cmd *cmd)
{
struct se_device *dev = cmd->se_dev;
unsigned char *rbuf;
@@ -97,10 +100,11 @@
buf[14] = 0x80;
rbuf = transport_kmap_data_sg(cmd);
- if (rbuf) {
- memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
- transport_kunmap_data_sg(cmd);
- }
+ if (!rbuf)
+ return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
+
+ memcpy(rbuf, buf, min_t(u32, sizeof(buf), cmd->data_length));
+ transport_kunmap_data_sg(cmd);
target_complete_cmd(cmd, GOOD);
return 0;
@@ -129,7 +133,8 @@
}
EXPORT_SYMBOL(spc_get_write_same_sectors);
-static int sbc_emulate_verify(struct se_cmd *cmd)
+static sense_reason_t
+sbc_emulate_verify(struct se_cmd *cmd)
{
target_complete_cmd(cmd, GOOD);
return 0;
@@ -313,13 +318,14 @@
kfree(buf);
}
-int sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
+sense_reason_t
+sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
{
struct se_device *dev = cmd->se_dev;
unsigned char *cdb = cmd->t_task_cdb;
unsigned int size;
u32 sectors = 0;
- int ret;
+ sense_reason_t ret;
switch (cdb[0]) {
case READ_6:
@@ -378,9 +384,9 @@
cmd->execute_cmd = ops->execute_rw;
break;
case XDWRITEREAD_10:
- if ((cmd->data_direction != DMA_TO_DEVICE) ||
+ if (cmd->data_direction != DMA_TO_DEVICE ||
!(cmd->se_cmd_flags & SCF_BIDI))
- goto out_invalid_cdb_field;
+ return TCM_INVALID_CDB_FIELD;
sectors = transport_get_sectors_10(cdb);
cmd->t_task_lba = transport_lba_32(cdb);
@@ -419,26 +425,26 @@
break;
case WRITE_SAME_32:
if (!ops->execute_write_same)
- goto out_unsupported_cdb;
+ return TCM_UNSUPPORTED_SCSI_OPCODE;
sectors = transport_get_sectors_32(cdb);
if (!sectors) {
pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
" supported\n");
- goto out_invalid_cdb_field;
+ return TCM_INVALID_CDB_FIELD;
}
size = sbc_get_size(cmd, 1);
cmd->t_task_lba = get_unaligned_be64(&cdb[12]);
if (sbc_write_same_supported(dev, &cdb[10]) < 0)
- goto out_unsupported_cdb;
+ return TCM_UNSUPPORTED_SCSI_OPCODE;
cmd->execute_cmd = ops->execute_write_same;
break;
default:
pr_err("VARIABLE_LENGTH_CMD service action"
" 0x%04x not supported\n", service_action);
- goto out_unsupported_cdb;
+ return TCM_UNSUPPORTED_SCSI_OPCODE;
}
break;
}
@@ -454,7 +460,7 @@
default:
pr_err("Unsupported SA: 0x%02x\n",
cmd->t_task_cdb[1] & 0x1f);
- goto out_invalid_cdb_field;
+ return TCM_INVALID_CDB_FIELD;
}
size = (cdb[10] << 24) | (cdb[11] << 16) |
(cdb[12] << 8) | cdb[13];
@@ -462,7 +468,7 @@
case SYNCHRONIZE_CACHE:
case SYNCHRONIZE_CACHE_16:
if (!ops->execute_sync_cache)
- goto out_unsupported_cdb;
+ return TCM_UNSUPPORTED_SCSI_OPCODE;
/*
* Extract LBA and range to be flushed for emulated SYNCHRONIZE_CACHE
@@ -483,42 +489,42 @@
*/
if (cmd->t_task_lba || sectors) {
if (sbc_check_valid_sectors(cmd) < 0)
- goto out_invalid_cdb_field;
+ return TCM_INVALID_CDB_FIELD;
}
cmd->execute_cmd = ops->execute_sync_cache;
break;
case UNMAP:
if (!ops->execute_unmap)
- goto out_unsupported_cdb;
+ return TCM_UNSUPPORTED_SCSI_OPCODE;
size = get_unaligned_be16(&cdb[7]);
cmd->execute_cmd = ops->execute_unmap;
break;
case WRITE_SAME_16:
if (!ops->execute_write_same)
- goto out_unsupported_cdb;
+ 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");
- goto out_invalid_cdb_field;
+ return TCM_INVALID_CDB_FIELD;
}
size = sbc_get_size(cmd, 1);
cmd->t_task_lba = get_unaligned_be64(&cdb[2]);
if (sbc_write_same_supported(dev, &cdb[1]) < 0)
- goto out_unsupported_cdb;
+ return TCM_UNSUPPORTED_SCSI_OPCODE;
cmd->execute_cmd = ops->execute_write_same;
break;
case WRITE_SAME:
if (!ops->execute_write_same)
- goto out_unsupported_cdb;
+ 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");
- goto out_invalid_cdb_field;
+ return TCM_INVALID_CDB_FIELD;
}
size = sbc_get_size(cmd, 1);
@@ -529,7 +535,7 @@
* of byte 1 bit 3 UNMAP instead of original reserved field
*/
if (sbc_write_same_supported(dev, &cdb[1]) < 0)
- goto out_unsupported_cdb;
+ return TCM_UNSUPPORTED_SCSI_OPCODE;
cmd->execute_cmd = ops->execute_write_same;
break;
case VERIFY:
@@ -556,7 +562,7 @@
/* reject any command that we don't have a handler for */
if (!(cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) && !cmd->execute_cmd)
- goto out_unsupported_cdb;
+ return TCM_UNSUPPORTED_SCSI_OPCODE;
if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
unsigned long long end_lba;
@@ -566,14 +572,14 @@
" big sectors %u exceeds fabric_max_sectors:"
" %u\n", cdb[0], sectors,
dev->dev_attrib.fabric_max_sectors);
- goto out_invalid_cdb_field;
+ return TCM_INVALID_CDB_FIELD;
}
if (sectors > dev->dev_attrib.hw_max_sectors) {
printk_ratelimited(KERN_ERR "SCSI OP %02xh with too"
" big sectors %u exceeds backend hw_max_sectors:"
" %u\n", cdb[0], sectors,
dev->dev_attrib.hw_max_sectors);
- goto out_invalid_cdb_field;
+ return TCM_INVALID_CDB_FIELD;
}
end_lba = dev->transport->get_blocks(dev) + 1;
@@ -581,26 +587,13 @@
pr_err("cmd exceeds last lba %llu "
"(lba %llu, sectors %u)\n",
end_lba, cmd->t_task_lba, sectors);
- goto out_invalid_cdb_field;
+ return TCM_INVALID_CDB_FIELD;
}
size = sbc_get_size(cmd, sectors);
}
- ret = target_cmd_size_check(cmd, size);
- if (ret < 0)
- return ret;
-
- return 0;
-
-out_unsupported_cdb:
- cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
- cmd->scsi_sense_reason = TCM_UNSUPPORTED_SCSI_OPCODE;
- return -EINVAL;
-out_invalid_cdb_field:
- cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
- cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
- return -EINVAL;
+ return target_cmd_size_check(cmd, size);
}
EXPORT_SYMBOL(sbc_parse_cdb);