@@ -123,8 +123,6 @@
#define ISER_QP_MAX_RECV_DTOS (ISER_DEF_XMIT_CMDS_MAX)
-#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 *
* to have at max for SCSI command. The tx posting & completion handling code *
@@ -452,9 +450,7 @@ struct iser_fr_pool {
*
* @cma_id: rdma_cm connection maneger handle
* @qp: Connection Queue-pair
- * @post_recv_buf_count: post receive counter
* @sig_count: send work request signal count
- * @rx_wr: receive work request for batch posts
* @device: reference to iser device
* @comp: iser completion context
* @fr_pool: connection fast registration poool
@@ -463,9 +459,7 @@ struct iser_fr_pool {
struct ib_conn {
struct rdma_cm_id *cma_id;
struct ib_qp *qp;
- int post_recv_buf_count;
u8 sig_count;
- struct ib_recv_wr rx_wr[ISER_MIN_POSTED_RX];
struct iser_device *device;
struct iser_comp *comp;
struct iser_fr_pool fr_pool;
@@ -482,8 +476,6 @@ struct ib_conn {
* @state: connection logical state
* @qp_max_recv_dtos: maximum number of data outs, corresponds
* to max number of post recvs
- * @qp_max_recv_dtos_mask: (qp_max_recv_dtos - 1)
- * @min_posted_rx: (qp_max_recv_dtos >> 2)
* @max_cmds: maximum cmds allowed for this connection
* @name: connection peer portal
* @release_work: deffered work for release job
@@ -494,7 +486,6 @@ struct ib_conn {
* (state is ISER_CONN_UP)
* @conn_list: entry in ig conn list
* @login_desc: login descriptor
- * @rx_desc_head: head of rx_descs cyclic buffer
* @rx_descs: rx buffers array (cyclic buffer)
* @num_rx_descs: number of rx descriptors
* @scsi_sg_tablesize: scsi host sg_tablesize
@@ -505,8 +496,6 @@ struct iser_conn {
struct iscsi_endpoint *ep;
enum iser_conn_state state;
unsigned qp_max_recv_dtos;
- unsigned qp_max_recv_dtos_mask;
- unsigned min_posted_rx;
u16 max_cmds;
char name[ISER_OBJECT_NAME_SIZE];
struct work_struct release_work;
@@ -516,7 +505,6 @@ struct iser_conn {
struct completion up_completion;
struct list_head conn_list;
struct iser_login_desc login_desc;
- unsigned int rx_desc_head;
struct iser_rx_desc *rx_descs;
u32 num_rx_descs;
unsigned short scsi_sg_tablesize;
@@ -638,7 +626,7 @@ void iser_unreg_mem_fastreg(struct iscsi_iser_task *iser_task,
enum iser_data_dir cmd_dir);
int iser_post_recvl(struct iser_conn *iser_conn);
-int iser_post_recvm(struct iser_conn *iser_conn, int count);
+int iser_post_recvm(struct iser_conn *iser_conn, struct iser_rx_desc *rx_desc);
int iser_post_send(struct ib_conn *ib_conn, struct iser_tx_desc *tx_desc,
bool signal);
@@ -247,8 +247,6 @@ int iser_alloc_rx_descriptors(struct iser_conn *iser_conn,
struct iser_device *device = ib_conn->device;
iser_conn->qp_max_recv_dtos = session->cmds_max;
- iser_conn->qp_max_recv_dtos_mask = session->cmds_max - 1; /* cmds_max is 2^N */
- iser_conn->min_posted_rx = iser_conn->qp_max_recv_dtos >> 2;
if (device->reg_ops->alloc_reg_res(ib_conn, session->scsi_cmds_max,
iser_conn->scsi_sg_tablesize))
@@ -279,7 +277,6 @@ int iser_alloc_rx_descriptors(struct iser_conn *iser_conn,
rx_sg->lkey = device->pd->local_dma_lkey;
}
- iser_conn->rx_desc_head = 0;
return 0;
rx_desc_dma_map_failed:
@@ -322,32 +319,36 @@ void iser_free_rx_descriptors(struct iser_conn *iser_conn)
static int iser_post_rx_bufs(struct iscsi_conn *conn, struct iscsi_hdr *req)
{
struct iser_conn *iser_conn = conn->dd_data;
- struct ib_conn *ib_conn = &iser_conn->ib_conn;
struct iscsi_session *session = conn->session;
+ int err = 0;
+ int i;
iser_dbg("req op %x flags %x\n", req->opcode, req->flags);
/* check if this is the last login - going to full feature phase */
if ((req->flags & ISCSI_FULL_FEATURE_PHASE) != ISCSI_FULL_FEATURE_PHASE)
- return 0;
-
- /*
- * Check that there is one posted recv buffer
- * (for the last login response).
- */
- WARN_ON(ib_conn->post_recv_buf_count != 1);
+ goto out;
if (session->discovery_sess) {
iser_info("Discovery session, re-using login RX buffer\n");
- return 0;
- } else
- iser_info("Normal session, posting batch of RX %d buffers\n",
- iser_conn->min_posted_rx);
+ goto out;
+ }
- /* Initial post receive buffers */
- if (iser_post_recvm(iser_conn, iser_conn->min_posted_rx))
- return -ENOMEM;
+ iser_info("Normal session, posting batch of RX %d buffers\n",
+ iser_conn->qp_max_recv_dtos - 1);
- return 0;
+ /*
+ * Initial post receive buffers.
+ * There is one already posted recv buffer (for the last login
+ * response). Therefore, the first recv buffer is skipped here.
+ */
+ for (i = 1; i < iser_conn->qp_max_recv_dtos; i++) {
+ if (iser_post_recvm(iser_conn, &iser_conn->rx_descs[i])) {
+ err = -ENOMEM;
+ break;
+ }
+ }
+out:
+ return err;
}
static inline bool iser_signal_comp(u8 sig_count)
@@ -585,7 +586,11 @@ void iser_login_rsp(struct ib_cq *cq, struct ib_wc *wc)
desc->rsp_dma, ISER_RX_LOGIN_SIZE,
DMA_FROM_DEVICE);
- ib_conn->post_recv_buf_count--;
+ if (iser_conn->iscsi_conn->session->discovery_sess)
+ return;
+
+ /* Post the first RX buffer that is skipped in iser_post_rx_bufs() */
+ iser_post_recvm(iser_conn, iser_conn->rx_descs);
}
static inline void
@@ -645,8 +650,7 @@ void iser_task_rsp(struct ib_cq *cq, struct ib_wc *wc)
struct iser_conn *iser_conn = to_iser_conn(ib_conn);
struct iser_rx_desc *desc = iser_rx(wc->wr_cqe);
struct iscsi_hdr *hdr;
- int length;
- int outstanding, count, err;
+ int length, err;
if (unlikely(wc->status != IB_WC_SUCCESS)) {
iser_err_comp(wc, "task_rsp");
@@ -675,20 +679,9 @@ void iser_task_rsp(struct ib_cq *cq, struct ib_wc *wc)
desc->dma_addr, ISER_RX_PAYLOAD_SIZE,
DMA_FROM_DEVICE);
- /* decrementing conn->post_recv_buf_count only --after-- freeing the *
- * task eliminates the need to worry on tasks which are completed in *
- * parallel to the execution of iser_conn_term. So the code that waits *
- * for the posted rx bufs refcount to become zero handles everything */
- ib_conn->post_recv_buf_count--;
-
- outstanding = ib_conn->post_recv_buf_count;
- if (outstanding + iser_conn->min_posted_rx <= iser_conn->qp_max_recv_dtos) {
- count = min(iser_conn->qp_max_recv_dtos - outstanding,
- iser_conn->min_posted_rx);
- err = iser_post_recvm(iser_conn, count);
- if (err)
- iser_err("posting %d rx bufs err %d\n", count, err);
- }
+ err = iser_post_recvm(iser_conn, desc);
+ if (err)
+ iser_err("posting rx buffer err %d\n", err);
}
void iser_cmd_comp(struct ib_cq *cq, struct ib_wc *wc)
@@ -936,7 +936,6 @@ void iser_conn_init(struct iser_conn *iser_conn)
INIT_LIST_HEAD(&iser_conn->conn_list);
mutex_init(&iser_conn->state_mutex);
- ib_conn->post_recv_buf_count = 0;
ib_conn->reg_cqe.done = iser_reg_comp;
}
@@ -1020,44 +1019,28 @@ int iser_post_recvl(struct iser_conn *iser_conn)
wr.num_sge = 1;
wr.next = NULL;
- ib_conn->post_recv_buf_count++;
ib_ret = ib_post_recv(ib_conn->qp, &wr, &wr_failed);
- if (ib_ret) {
+ if (ib_ret)
iser_err("ib_post_recv failed ret=%d\n", ib_ret);
- ib_conn->post_recv_buf_count--;
- }
return ib_ret;
}
-int iser_post_recvm(struct iser_conn *iser_conn, int count)
+int iser_post_recvm(struct iser_conn *iser_conn, struct iser_rx_desc *rx_desc)
{
struct ib_conn *ib_conn = &iser_conn->ib_conn;
- unsigned int my_rx_head = iser_conn->rx_desc_head;
- struct iser_rx_desc *rx_desc;
- struct ib_recv_wr *wr, *wr_failed;
- int i, ib_ret;
-
- for (wr = ib_conn->rx_wr, i = 0; i < count; i++, wr++) {
- rx_desc = &iser_conn->rx_descs[my_rx_head];
- rx_desc->cqe.done = iser_task_rsp;
- wr->wr_cqe = &rx_desc->cqe;
- wr->sg_list = &rx_desc->rx_sg;
- wr->num_sge = 1;
- wr->next = wr + 1;
- my_rx_head = (my_rx_head + 1) & iser_conn->qp_max_recv_dtos_mask;
- }
+ struct ib_recv_wr wr, *wr_failed;
+ int ib_ret;
- wr--;
- wr->next = NULL; /* mark end of work requests list */
+ rx_desc->cqe.done = iser_task_rsp;
+ wr.wr_cqe = &rx_desc->cqe;
+ wr.sg_list = &rx_desc->rx_sg;
+ wr.num_sge = 1;
+ wr.next = NULL;
- ib_conn->post_recv_buf_count += count;
- ib_ret = ib_post_recv(ib_conn->qp, ib_conn->rx_wr, &wr_failed);
- if (ib_ret) {
+ ib_ret = ib_post_recv(ib_conn->qp, &wr, &wr_failed);
+ if (ib_ret)
iser_err("ib_post_recv failed ret=%d\n", ib_ret);
- ib_conn->post_recv_buf_count -= count;
- } else
- iser_conn->rx_desc_head = my_rx_head;
return ib_ret;
}