IB/iser: Accept session->cmds_max from user space
Use cmds_max passed from user space to be the number of PDUs to be
supported for the session instead of hard-coded ISCSI_DEF_XMIT_CMDS_MAX.
This allow controlling the max number of SCSI commands for the session.
Also don't ignore the qdepth passed from user space.
Derive from session->cmds_max the actual number of RX buffers and FMR
pool size to allocate during the connection bind phase.
Since the iser transport connection is established before the iscsi
session/connection are created and bound, we still use one hard-coded
quantity ISER_DEF_XMIT_CMDS_MAX to compute the maximum number of
work-requests to be supported by the RC QP used for the connection.
The above quantity is made to be a power of two between ISCSI_TOTAL_CMDS_MIN
(16) and ISER_DEF_XMIT_CMDS_MAX (512) inclusive.
Signed-off-by: Shlomo Pongratz <shlomop@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.h b/drivers/infiniband/ulp/iser/iscsi_iser.h
index fee88290..d2fc55a 100644
--- a/drivers/infiniband/ulp/iser/iscsi_iser.h
+++ b/drivers/infiniband/ulp/iser/iscsi_iser.h
@@ -102,7 +102,13 @@
/* support up to 512KB in one RDMA */
#define ISCSI_ISER_SG_TABLESIZE (0x80000 >> SHIFT_4K)
-#define ISER_DEF_CMD_PER_LUN ISCSI_DEF_XMIT_CMDS_MAX
+#define ISER_DEF_XMIT_CMDS_DEFAULT 512
+#if ISCSI_DEF_XMIT_CMDS_MAX > ISER_DEF_XMIT_CMDS_DEFAULT
+ #define ISER_DEF_XMIT_CMDS_MAX ISCSI_DEF_XMIT_CMDS_MAX
+#else
+ #define ISER_DEF_XMIT_CMDS_MAX ISER_DEF_XMIT_CMDS_DEFAULT
+#endif
+#define ISER_DEF_CMD_PER_LUN ISER_DEF_XMIT_CMDS_MAX
/* QP settings */
/* Maximal bounds on received asynchronous PDUs */
@@ -111,9 +117,9 @@
#define ISER_MAX_TX_MISC_PDUS 6 /* NOOP_OUT(2), TEXT(1), *
* SCSI_TMFUNC(2), LOGOUT(1) */
-#define ISER_QP_MAX_RECV_DTOS (ISCSI_DEF_XMIT_CMDS_MAX)
+#define ISER_QP_MAX_RECV_DTOS (ISER_DEF_XMIT_CMDS_MAX)
-#define ISER_MIN_POSTED_RX (ISCSI_DEF_XMIT_CMDS_MAX >> 2)
+#define ISER_MIN_POSTED_RX (ISER_DEF_XMIT_CMDS_MAX >> 2)
/* the max TX (send) WR supported by the iSER QP is defined by *
* max_send_wr = T * (1 + D) + C ; D is how many inflight dataouts we expect *
@@ -123,7 +129,7 @@
#define ISER_INFLIGHT_DATAOUTS 8
-#define ISER_QP_MAX_REQ_DTOS (ISCSI_DEF_XMIT_CMDS_MAX * \
+#define ISER_QP_MAX_REQ_DTOS (ISER_DEF_XMIT_CMDS_MAX * \
(1 + ISER_INFLIGHT_DATAOUTS) + \
ISER_MAX_TX_MISC_PDUS + \
ISER_MAX_RX_MISC_PDUS)
@@ -272,6 +278,9 @@
struct ib_qp *qp; /* QP */
struct ib_fmr_pool *fmr_pool; /* pool of IB FMRs */
wait_queue_head_t wait; /* waitq for conn/disconn */
+ unsigned qp_max_recv_dtos; /* num of rx buffers */
+ unsigned qp_max_recv_dtos_mask; /* above minus 1 */
+ unsigned min_posted_rx; /* qp_max_recv_dtos >> 2 */
int post_recv_buf_count; /* posted rx count */
atomic_t post_send_buf_count; /* posted tx count */
char name[ISER_OBJECT_NAME_SIZE];
@@ -394,7 +403,7 @@
void iser_dma_unmap_task_data(struct iscsi_iser_task *iser_task);
int iser_initialize_task_headers(struct iscsi_task *task,
struct iser_tx_desc *tx_desc);
-int iser_alloc_rx_descriptors(struct iser_conn *ib_conn);
-int iser_create_fmr_pool(struct iser_conn *ib_conn);
+int iser_alloc_rx_descriptors(struct iser_conn *ib_conn, struct iscsi_session *session);
+int iser_create_fmr_pool(struct iser_conn *ib_conn, unsigned cmds_max);
void iser_free_fmr_pool(struct iser_conn *ib_conn);
#endif