[SCSI] libiscsi: allow drivers to modify the itt sent to the target

bnx2i and cxgb3i need to encode LLD info in the itt so that
the firmware/hardware can process the pdu. This patch allows
the LLDs to encode info in the task->hdr->itt that they
setup in the alloc_pdu callout (any resources that are allocated
can be freed with the pdu in the cleanup_task callout). If
the LLD encodes info in the itt they should implement a
parse_pdu_itt callout. If parse_pdu_itt is not implemented
libiscsi will do the right thing for the LLD.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
This commit is contained in:
Mike Christie 2008-12-02 00:32:13 -06:00 committed by James Bottomley
parent 38e1a8f547
commit 262ef63627
3 changed files with 40 additions and 15 deletions

View File

@ -222,12 +222,14 @@ static int iscsi_prep_scsi_cmd_pdu(struct iscsi_task *task)
struct scsi_cmnd *sc = task->sc;
struct iscsi_cmd *hdr;
unsigned hdrlength, cmd_len;
itt_t itt;
int rc;
rc = conn->session->tt->alloc_pdu(task);
if (rc)
return rc;
hdr = (struct iscsi_cmd *) task->hdr;
itt = hdr->itt;
memset(hdr, 0, sizeof(*hdr));
task->hdr_len = 0;
@ -238,7 +240,11 @@ static int iscsi_prep_scsi_cmd_pdu(struct iscsi_task *task)
hdr->flags = ISCSI_ATTR_SIMPLE;
int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun);
memcpy(task->lun, hdr->lun, sizeof(task->lun));
hdr->itt = task->hdr_itt = build_itt(task->itt, session->age);
if (session->tt->parse_pdu_itt)
hdr->itt = task->hdr_itt = itt;
else
hdr->itt = task->hdr_itt = build_itt(task->itt,
task->conn->session->age);
hdr->cmdsn = task->cmdsn = cpu_to_be32(session->cmdsn);
session->cmdsn++;
hdr->exp_statsn = cpu_to_be32(conn->exp_statsn);
@ -457,7 +463,6 @@ static int iscsi_prep_mgmt_task(struct iscsi_conn *conn,
*/
nop->cmdsn = cpu_to_be32(session->cmdsn);
if (hdr->itt != RESERVED_ITT) {
hdr->itt = build_itt(task->itt, session->age);
/*
* TODO: We always use immediate, so we never hit this.
* If we start to send tmfs or nops as non-immediate then
@ -490,6 +495,7 @@ __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
{
struct iscsi_session *session = conn->session;
struct iscsi_task *task;
itt_t itt;
if (session->state == ISCSI_STATE_TERMINATE)
return NULL;
@ -531,9 +537,18 @@ __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
"pdu for mgmt task.\n");
goto requeue_task;
}
itt = task->hdr->itt;
task->hdr_len = sizeof(struct iscsi_hdr);
memcpy(task->hdr, hdr, sizeof(struct iscsi_hdr));
if (hdr->itt != RESERVED_ITT) {
if (session->tt->parse_pdu_itt)
task->hdr->itt = itt;
else
task->hdr->itt = build_itt(task->itt,
task->conn->session->age);
}
INIT_LIST_HEAD(&task->running);
list_add_tail(&task->running, &conn->mgmtqueue);
@ -745,7 +760,6 @@ static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
{
struct iscsi_reject *reject = (struct iscsi_reject *)hdr;
struct iscsi_hdr rejected_pdu;
uint32_t itt;
conn->exp_statsn = be32_to_cpu(reject->statsn) + 1;
@ -755,10 +769,9 @@ static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
if (ntoh24(reject->dlength) >= sizeof(struct iscsi_hdr)) {
memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr));
itt = get_itt(rejected_pdu.itt);
iscsi_conn_printk(KERN_ERR, conn,
"itt 0x%x had pdu (op 0x%x) rejected "
"due to DataDigest error.\n", itt,
"pdu (op 0x%x) rejected "
"due to DataDigest error.\n",
rejected_pdu.opcode);
}
}
@ -778,12 +791,15 @@ static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
static struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *conn, itt_t itt)
{
struct iscsi_session *session = conn->session;
uint32_t i;
int i;
if (itt == RESERVED_ITT)
return NULL;
i = get_itt(itt);
if (session->tt->parse_pdu_itt)
session->tt->parse_pdu_itt(conn, itt, &i, NULL);
else
i = get_itt(itt);
if (i >= session->cmds_max)
return NULL;
@ -958,20 +974,25 @@ EXPORT_SYMBOL_GPL(iscsi_complete_pdu);
int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt)
{
struct iscsi_session *session = conn->session;
uint32_t i;
int age = 0, i = 0;
if (itt == RESERVED_ITT)
return 0;
if (((__force u32)itt & ISCSI_AGE_MASK) !=
(session->age << ISCSI_AGE_SHIFT)) {
if (session->tt->parse_pdu_itt)
session->tt->parse_pdu_itt(conn, itt, &i, &age);
else {
i = get_itt(itt);
age = ((__force u32)itt >> ISCSI_AGE_SHIFT) & ISCSI_AGE_MASK;
}
if (age != session->age) {
iscsi_conn_printk(KERN_ERR, conn,
"received itt %x expected session age (%x)\n",
(__force u32)itt, session->age);
return ISCSI_ERR_BAD_ITT;
}
i = get_itt(itt);
if (i >= session->cmds_max) {
iscsi_conn_printk(KERN_ERR, conn,
"received invalid itt index %u (max cmds "

View File

@ -30,6 +30,7 @@
#include <linux/workqueue.h>
#include <scsi/iscsi_proto.h>
#include <scsi/iscsi_if.h>
#include <scsi/scsi_transport_iscsi.h>
struct scsi_transport_template;
struct scsi_host_template;
@ -70,12 +71,12 @@ enum {
/* Connection suspend "bit" */
#define ISCSI_SUSPEND_BIT 1
#define ISCSI_ITT_MASK (0x1fff)
#define ISCSI_ITT_MASK 0x1fff
#define ISCSI_TOTAL_CMDS_MAX 4096
/* this must be a power of two greater than ISCSI_MGMT_CMDS_MAX */
#define ISCSI_TOTAL_CMDS_MIN 16
#define ISCSI_AGE_SHIFT 28
#define ISCSI_AGE_MASK (0xf << ISCSI_AGE_SHIFT)
#define ISCSI_AGE_MASK 0xf
#define ISCSI_ADDRESS_BUF_LEN 64

View File

@ -122,6 +122,9 @@ struct iscsi_transport {
int (*xmit_pdu) (struct iscsi_task *task);
int (*init_pdu) (struct iscsi_task *task, unsigned int offset,
unsigned int count);
void (*parse_pdu_itt) (struct iscsi_conn *conn, itt_t itt,
int *index, int *age);
void (*session_recovery_timedout) (struct iscsi_cls_session *session);
struct iscsi_endpoint *(*ep_connect) (struct sockaddr *dst_addr,
int non_blocking);