[SCSI] iscsi_tcp: convert to new alloc_hdr api
This converts iscsi_tcp to the new api and modifies how
it handles r2ts.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
index 464de78..97bad5c 100644
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -57,13 +57,6 @@
#define debug_tcp(fmt...)
#endif
-#ifndef DEBUG_ASSERT
-#ifdef BUG_ON
-#undef BUG_ON
-#endif
-#define BUG_ON(expr)
-#endif
-
static struct scsi_transport_template *iscsi_tcp_scsi_transport;
static struct scsi_host_template iscsi_sht;
static struct iscsi_transport iscsi_tcp_transport;
@@ -498,14 +491,13 @@
/*
* must be called with session lock
*/
-static void
-iscsi_tcp_cleanup_task(struct iscsi_conn *conn, struct iscsi_task *task)
+static void iscsi_tcp_cleanup_task(struct iscsi_task *task)
{
struct iscsi_tcp_task *tcp_task = task->dd_data;
struct iscsi_r2t_info *r2t;
- /* nothing to do for mgmt tasks */
- if (!task->sc)
+ /* nothing to do for mgmt or pending tasks */
+ if (!task->sc || task->state == ISCSI_TASK_PENDING)
return;
/* flush task's r2t queues */
@@ -611,11 +603,11 @@
static int
iscsi_r2t_rsp(struct iscsi_conn *conn, struct iscsi_task *task)
{
- struct iscsi_r2t_info *r2t;
struct iscsi_session *session = conn->session;
struct iscsi_tcp_task *tcp_task = task->dd_data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_r2t_rsp *rhdr = (struct iscsi_r2t_rsp *)tcp_conn->in.hdr;
+ struct iscsi_r2t_info *r2t;
int r2tsn = be32_to_cpu(rhdr->r2tsn);
int rc;
@@ -643,7 +635,12 @@
}
rc = __kfifo_get(tcp_task->r2tpool.queue, (void*)&r2t, sizeof(void*));
- BUG_ON(!rc);
+ if (!rc) {
+ iscsi_conn_printk(KERN_ERR, conn, "Could not allocate R2T. "
+ "Target has sent more R2Ts than it "
+ "negotiated for or driver has has leaked.\n");
+ return ISCSI_ERR_PROTO;
+ }
r2t->exp_statsn = rhdr->statsn;
r2t->data_length = be32_to_cpu(rhdr->data_length);
@@ -672,9 +669,8 @@
}
r2t->ttt = rhdr->ttt; /* no flip */
- r2t->solicit_datasn = 0;
-
- iscsi_solicit_data_init(conn, task, r2t);
+ r2t->datasn = 0;
+ r2t->sent = 0;
tcp_task->exp_datasn = r2tsn + 1;
__kfifo_put(tcp_task->r2tqueue, (void*)&r2t, sizeof(void*));
@@ -1199,9 +1195,9 @@
return segment->total_copied - segment->total_size;
}
-static inline int
-iscsi_tcp_flush(struct iscsi_conn *conn)
+static int iscsi_tcp_flush(struct iscsi_task *task)
{
+ struct iscsi_conn *conn = task->conn;
int rc;
while (iscsi_tcp_xmit_qlen(conn)) {
@@ -1364,14 +1360,49 @@
return 1;
}
+static int iscsi_tcp_pdu_init(struct iscsi_task *task,
+ unsigned int offset, unsigned int count)
+{
+ struct iscsi_conn *conn = task->conn;
+ int err = 0;
+
+ iscsi_tcp_send_hdr_prep(conn, task->hdr, task->hdr_len);
+
+ if (!count)
+ return 0;
+
+ if (!task->sc)
+ iscsi_tcp_send_linear_data_prepare(conn, task->data, count);
+ else {
+ struct scsi_data_buffer *sdb = scsi_out(task->sc);
+
+ err = iscsi_tcp_send_data_prep(conn, sdb->table.sgl,
+ sdb->table.nents, offset, count);
+ }
+
+ if (err) {
+ iscsi_conn_failure(conn, err);
+ return -EIO;
+ }
+ return 0;
+}
+
+static int iscsi_tcp_pdu_alloc(struct iscsi_task *task)
+{
+ struct iscsi_tcp_task *tcp_task = task->dd_data;
+
+ task->hdr = &tcp_task->hdr.hdrbuf;
+ task->hdr_max = sizeof(tcp_task->hdr) - ISCSI_DIGEST_SIZE;
+ return 0;
+}
+
/**
* iscsi_tcp_task - Initialize iSCSI SCSI_READ or SCSI_WRITE commands
* @conn: iscsi connection
* @task: scsi command task
* @sc: scsi command
**/
-static int
-iscsi_tcp_task_init(struct iscsi_task *task)
+static int iscsi_tcp_task_init(struct iscsi_task *task)
{
struct iscsi_tcp_task *tcp_task = task->dd_data;
struct iscsi_conn *conn = task->conn;
@@ -1386,40 +1417,57 @@
debug_scsi("mtask deq [cid %d itt 0x%x]\n", conn->id,
task->itt);
- /* Prepare PDU, optionally w/ immediate data */
- iscsi_tcp_send_hdr_prep(conn, task->hdr, sizeof(*task->hdr));
-
- /* If we have immediate data, attach a payload */
- if (task->data_count)
- iscsi_tcp_send_linear_data_prepare(conn, task->data,
- task->data_count);
- return 0;
+ return conn->session->tt->init_pdu(task, 0, task->data_count);
}
BUG_ON(__kfifo_len(tcp_task->r2tqueue));
- tcp_task->sent = 0;
tcp_task->exp_datasn = 0;
/* Prepare PDU, optionally w/ immediate data */
debug_scsi("task deq [cid %d itt 0x%x imm %d unsol %d]\n",
conn->id, task->itt, task->imm_count,
- task->unsol_count);
- iscsi_tcp_send_hdr_prep(conn, task->hdr, task->hdr_len);
+ task->unsol_r2t.data_length);
- if (!task->imm_count)
- return 0;
-
- /* If we have immediate data, attach a payload */
- err = iscsi_tcp_send_data_prep(conn, scsi_out(sc)->table.sgl,
- scsi_out(sc)->table.nents,
- 0, task->imm_count);
+ err = conn->session->tt->init_pdu(task, 0, task->imm_count);
if (err)
return err;
- tcp_task->sent += task->imm_count;
task->imm_count = 0;
return 0;
}
+static struct iscsi_r2t_info *iscsi_tcp_get_curr_r2t(struct iscsi_task *task)
+{
+ struct iscsi_session *session = task->conn->session;
+ struct iscsi_tcp_task *tcp_task = task->dd_data;
+ struct iscsi_r2t_info *r2t = NULL;
+
+ if (iscsi_task_has_unsol_data(task))
+ r2t = &task->unsol_r2t;
+ else {
+ spin_lock_bh(&session->lock);
+ if (tcp_task->r2t) {
+ r2t = tcp_task->r2t;
+ /* Continue with this R2T? */
+ if (r2t->data_length <= r2t->sent) {
+ debug_scsi(" done with r2t %p\n", r2t);
+ __kfifo_put(tcp_task->r2tpool.queue,
+ (void *)&tcp_task->r2t,
+ sizeof(void *));
+ tcp_task->r2t = r2t = NULL;
+ }
+ }
+
+ if (r2t == NULL) {
+ __kfifo_get(tcp_task->r2tqueue,
+ (void *)&tcp_task->r2t, sizeof(void *));
+ r2t = tcp_task->r2t;
+ }
+ spin_unlock_bh(&session->lock);
+ }
+
+ return r2t;
+}
+
/*
* iscsi_tcp_task_xmit - xmit normal PDU task
* @task: iscsi command task
@@ -1428,108 +1476,52 @@
* -EAGAIN if there's still data in the queue, or != 0 for any other kind
* of error.
*/
-static int
-iscsi_tcp_task_xmit(struct iscsi_task *task)
+static int iscsi_tcp_task_xmit(struct iscsi_task *task)
{
struct iscsi_conn *conn = task->conn;
- struct iscsi_tcp_task *tcp_task = task->dd_data;
- struct scsi_cmnd *sc = task->sc;
- struct scsi_data_buffer *sdb;
+ struct iscsi_session *session = conn->session;
+ struct iscsi_r2t_info *r2t;
int rc = 0;
flush:
/* Flush any pending data first. */
- rc = iscsi_tcp_flush(conn);
+ rc = session->tt->xmit_pdu(task);
if (rc < 0)
return rc;
/* mgmt command */
- if (!sc) {
+ if (!task->sc) {
if (task->hdr->itt == RESERVED_ITT)
iscsi_put_task(task);
return 0;
}
/* Are we done already? */
- if (sc->sc_data_direction != DMA_TO_DEVICE)
+ if (task->sc->sc_data_direction != DMA_TO_DEVICE)
return 0;
- sdb = scsi_out(sc);
- if (task->unsol_count != 0) {
- struct iscsi_data *hdr = &tcp_task->unsol_dtask.hdr;
-
- /* Prepare a header for the unsolicited PDU.
- * The amount of data we want to send will be
- * in task->data_count.
- * FIXME: return the data count instead.
- */
- iscsi_prep_unsolicit_data_pdu(task, hdr);
-
- debug_tcp("unsol dout [itt 0x%x doff %d dlen %d]\n",
- task->itt, tcp_task->sent, task->data_count);
-
- iscsi_tcp_send_hdr_prep(conn, hdr, sizeof(*hdr));
- rc = iscsi_tcp_send_data_prep(conn, sdb->table.sgl,
- sdb->table.nents, tcp_task->sent,
- task->data_count);
- if (rc)
- goto fail;
- tcp_task->sent += task->data_count;
- task->unsol_count -= task->data_count;
- goto flush;
- } else {
- struct iscsi_session *session = conn->session;
- struct iscsi_r2t_info *r2t;
-
- /* All unsolicited PDUs sent. Check for solicited PDUs.
- */
- spin_lock_bh(&session->lock);
- r2t = tcp_task->r2t;
- if (r2t != NULL) {
- /* Continue with this R2T? */
- if (!iscsi_solicit_data_cont(conn, task, r2t)) {
- debug_scsi(" done with r2t %p\n", r2t);
-
- __kfifo_put(tcp_task->r2tpool.queue,
- (void*)&r2t, sizeof(void*));
- tcp_task->r2t = r2t = NULL;
- }
- }
-
- if (r2t == NULL) {
- __kfifo_get(tcp_task->r2tqueue, (void*)&tcp_task->r2t,
- sizeof(void*));
- r2t = tcp_task->r2t;
- }
- spin_unlock_bh(&session->lock);
-
+ r2t = iscsi_tcp_get_curr_r2t(task);
+ if (r2t == NULL) {
/* Waiting for more R2Ts to arrive. */
- if (r2t == NULL) {
- debug_tcp("no R2Ts yet\n");
- return 0;
- }
-
- debug_scsi("sol dout %p [dsn %d itt 0x%x doff %d dlen %d]\n",
- r2t, r2t->solicit_datasn - 1, task->itt,
- r2t->data_offset + r2t->sent, r2t->data_count);
-
- iscsi_tcp_send_hdr_prep(conn, &r2t->dtask.hdr,
- sizeof(struct iscsi_hdr));
-
- rc = iscsi_tcp_send_data_prep(conn, sdb->table.sgl,
- sdb->table.nents,
- r2t->data_offset + r2t->sent,
- r2t->data_count);
- if (rc)
- goto fail;
- tcp_task->sent += r2t->data_count;
- r2t->sent += r2t->data_count;
- goto flush;
+ debug_tcp("no R2Ts yet\n");
+ return 0;
}
- return 0;
-fail:
- iscsi_conn_failure(conn, rc);
- return -EIO;
+
+ rc = conn->session->tt->alloc_pdu(task);
+ if (rc)
+ return rc;
+ iscsi_prep_data_out_pdu(task, r2t, (struct iscsi_data *) task->hdr);
+
+ debug_scsi("sol dout %p [dsn %d itt 0x%x doff %d dlen %d]\n",
+ r2t, r2t->datasn - 1, task->hdr->itt,
+ r2t->data_offset + r2t->sent, r2t->data_count);
+
+ rc = conn->session->tt->init_pdu(task, r2t->data_offset + r2t->sent,
+ r2t->data_count);
+ if (rc)
+ return rc;
+ r2t->sent += r2t->data_count;
+ goto flush;
}
static struct iscsi_cls_conn *
@@ -1751,13 +1743,14 @@
struct iscsi_tcp_task *tcp_task = task->dd_data;
/*
- * pre-allocated x4 as much r2ts to handle race when
+ * pre-allocated x2 as much r2ts to handle race when
* target acks DataOut faster than we data_xmit() queues
* could replenish r2tqueue.
*/
/* R2T pool */
- if (iscsi_pool_init(&tcp_task->r2tpool, session->max_r2t * 4, NULL,
+ if (iscsi_pool_init(&tcp_task->r2tpool,
+ session->max_r2t * 2, NULL,
sizeof(struct iscsi_r2t_info))) {
goto r2t_alloc_fail;
}
@@ -1891,7 +1884,6 @@
struct iscsi_cls_session *cls_session;
struct iscsi_session *session;
struct Scsi_Host *shost;
- int cmd_i;
if (ep) {
printk(KERN_ERR "iscsi_tcp: invalid ep %p.\n", ep);
@@ -1919,14 +1911,6 @@
session = cls_session->dd_data;
shost->can_queue = session->scsi_cmds_max;
- for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
- struct iscsi_task *task = session->cmds[cmd_i];
- struct iscsi_tcp_task *tcp_task = task->dd_data;
-
- task->hdr = &tcp_task->hdr.cmd_hdr;
- task->hdr_max = sizeof(tcp_task->hdr) - ISCSI_DIGEST_SIZE;
- }
-
if (iscsi_r2tpool_alloc(session))
goto remove_session;
return cls_session;
@@ -2026,9 +2010,14 @@
/* IO */
.send_pdu = iscsi_conn_send_pdu,
.get_stats = iscsi_conn_get_stats,
+ /* iscsi task/cmd helpers */
.init_task = iscsi_tcp_task_init,
.xmit_task = iscsi_tcp_task_xmit,
.cleanup_task = iscsi_tcp_cleanup_task,
+ /* low level pdu helpers */
+ .xmit_pdu = iscsi_tcp_flush,
+ .init_pdu = iscsi_tcp_pdu_init,
+ .alloc_pdu = iscsi_tcp_pdu_alloc,
/* recovery */
.session_recovery_timedout = iscsi_session_recovery_timedout,
};