target: split overflow and underflow checks into a helper

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This commit is contained in:
Christoph Hellwig 2012-05-20 11:59:12 -04:00 committed by Nicholas Bellinger
parent 64f1db38c6
commit 9b3b804101

View file

@ -1345,6 +1345,55 @@ static inline void transport_generic_prepare_cdb(
static int transport_generic_cmd_sequencer(struct se_cmd *, unsigned char *);
static int target_cmd_size_check(struct se_cmd *cmd, unsigned int size)
{
struct se_device *dev = cmd->se_dev;
if (cmd->unknown_data_length) {
cmd->data_length = size;
} else if (size != cmd->data_length) {
pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
" %u does not match SCSI CDB Length: %u for SAM Opcode:"
" 0x%02x\n", cmd->se_tfo->get_fabric_name(),
cmd->data_length, size, cmd->t_task_cdb[0]);
cmd->cmd_spdtl = size;
if (cmd->data_direction == DMA_TO_DEVICE) {
pr_err("Rejecting underflow/overflow"
" WRITE data\n");
goto out_invalid_cdb_field;
}
/*
* Reject READ_* or WRITE_* with overflow/underflow for
* type SCF_SCSI_DATA_CDB.
*/
if (dev->se_sub_dev->se_dev_attrib.block_size != 512) {
pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
" CDB on non 512-byte sector setup subsystem"
" plugin: %s\n", dev->transport->name);
/* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
goto out_invalid_cdb_field;
}
if (size > cmd->data_length) {
cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
cmd->residual_count = (size - cmd->data_length);
} else {
cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
cmd->residual_count = (cmd->data_length - size);
}
cmd->data_length = size;
}
return 0;
out_invalid_cdb_field:
cmd->se_cmd_flags |= SCF_SCSI_CDB_EXCEPTION;
cmd->scsi_sense_reason = TCM_INVALID_CDB_FIELD;
return -EINVAL;
}
/*
* Used by fabric modules containing a local struct se_cmd within their
* fabric dependent per I/O descriptor.
@ -2431,6 +2480,7 @@ static int transport_generic_cmd_sequencer(
int sector_ret = 0, passthrough;
u32 sectors = 0, size = 0;
u16 service_action;
int ret;
/*
* If we operate in passthrough mode we skip most CDB emulation and
@ -2929,43 +2979,9 @@ static int transport_generic_cmd_sequencer(
goto out_unsupported_cdb;
}
if (cmd->unknown_data_length)
cmd->data_length = size;
if (size != cmd->data_length) {
pr_warn("TARGET_CORE[%s]: Expected Transfer Length:"
" %u does not match SCSI CDB Length: %u for SAM Opcode:"
" 0x%02x\n", cmd->se_tfo->get_fabric_name(),
cmd->data_length, size, cdb[0]);
cmd->cmd_spdtl = size;
if (cmd->data_direction == DMA_TO_DEVICE) {
pr_err("Rejecting underflow/overflow"
" WRITE data\n");
goto out_invalid_cdb_field;
}
/*
* Reject READ_* or WRITE_* with overflow/underflow for
* type SCF_SCSI_DATA_CDB.
*/
if (dev->se_sub_dev->se_dev_attrib.block_size != 512) {
pr_err("Failing OVERFLOW/UNDERFLOW for LBA op"
" CDB on non 512-byte sector setup subsystem"
" plugin: %s\n", dev->transport->name);
/* Returns CHECK_CONDITION + INVALID_CDB_FIELD */
goto out_invalid_cdb_field;
}
if (size > cmd->data_length) {
cmd->se_cmd_flags |= SCF_OVERFLOW_BIT;
cmd->residual_count = (size - cmd->data_length);
} else {
cmd->se_cmd_flags |= SCF_UNDERFLOW_BIT;
cmd->residual_count = (cmd->data_length - size);
}
cmd->data_length = size;
}
ret = target_cmd_size_check(cmd, size);
if (ret)
return ret;
if (cmd->se_cmd_flags & SCF_SCSI_DATA_CDB) {
if (sectors > su_dev->se_dev_attrib.fabric_max_sectors) {