From bcc60c381d857ced653e912cbe6121294773e147 Mon Sep 17 00:00:00 2001 From: Or Gerlitz Date: Mon, 8 Feb 2010 13:17:42 +0000 Subject: IB/iser: New receive buffer posting logic Currently, the recv buffer posting logic is based on the transactional nature of iSER which allows for posting a buffer before sending a PDU. Change this to post only when the number of outstanding recv buffers is below a water mark and in a batched manner, thus simplifying and optimizing the data path. Use a pre-allocated ring of recv buffers instead of allocating from kmem cache. A special treatment is given to the login response buffer whose size must be 8K unlike the size of buffers used for any other purpose which is 128 bytes. Signed-off-by: Or Gerlitz Signed-off-by: Roland Dreier --- drivers/infiniband/ulp/iser/iser_initiator.c | 235 +++++++++++++-------------- 1 file changed, 116 insertions(+), 119 deletions(-) (limited to 'drivers/infiniband/ulp/iser/iser_initiator.c') diff --git a/drivers/infiniband/ulp/iser/iser_initiator.c b/drivers/infiniband/ulp/iser/iser_initiator.c index 5f42fbe..6d9bbe6 100644 --- a/drivers/infiniband/ulp/iser/iser_initiator.c +++ b/drivers/infiniband/ulp/iser/iser_initiator.c @@ -39,9 +39,6 @@ #include "iscsi_iser.h" -/* Constant PDU lengths calculations */ -#define ISER_TOTAL_HEADERS_LEN (sizeof (struct iser_hdr) + \ - sizeof (struct iscsi_hdr)) /* iser_dto_add_regd_buff - increments the reference count for * * the registered buffer & adds it to the DTO object */ @@ -172,78 +169,6 @@ iser_prepare_write_cmd(struct iscsi_task *task, return 0; } -/** - * iser_post_receive_control - allocates, initializes and posts receive DTO. - */ -static int iser_post_receive_control(struct iscsi_conn *conn) -{ - struct iscsi_iser_conn *iser_conn = conn->dd_data; - struct iser_desc *rx_desc; - struct iser_regd_buf *regd_hdr; - struct iser_regd_buf *regd_data; - struct iser_dto *recv_dto = NULL; - struct iser_device *device = iser_conn->ib_conn->device; - int rx_data_size, err = 0; - - rx_desc = kmem_cache_alloc(ig.desc_cache, GFP_NOIO); - if (rx_desc == NULL) { - iser_err("Failed to alloc desc for post recv\n"); - return -ENOMEM; - } - rx_desc->type = ISCSI_RX; - - /* for the login sequence we must support rx of upto 8K; login is done - * after conn create/bind (connect) and conn stop/bind (reconnect), - * what's common for both schemes is that the connection is not started - */ - if (conn->c_stage != ISCSI_CONN_STARTED) - rx_data_size = ISCSI_DEF_MAX_RECV_SEG_LEN; - else /* FIXME till user space sets conn->max_recv_dlength correctly */ - rx_data_size = 128; - - rx_desc->data = kmalloc(rx_data_size, GFP_NOIO); - if (rx_desc->data == NULL) { - iser_err("Failed to alloc data buf for post recv\n"); - err = -ENOMEM; - goto post_rx_kmalloc_failure; - } - - recv_dto = &rx_desc->dto; - recv_dto->ib_conn = iser_conn->ib_conn; - recv_dto->regd_vector_len = 0; - - regd_hdr = &rx_desc->hdr_regd_buf; - memset(regd_hdr, 0, sizeof(struct iser_regd_buf)); - regd_hdr->device = device; - regd_hdr->virt_addr = rx_desc; /* == &rx_desc->iser_header */ - regd_hdr->data_size = ISER_TOTAL_HEADERS_LEN; - - iser_reg_single(device, regd_hdr, DMA_FROM_DEVICE); - - iser_dto_add_regd_buff(recv_dto, regd_hdr, 0, 0); - - regd_data = &rx_desc->data_regd_buf; - memset(regd_data, 0, sizeof(struct iser_regd_buf)); - regd_data->device = device; - regd_data->virt_addr = rx_desc->data; - regd_data->data_size = rx_data_size; - - iser_reg_single(device, regd_data, DMA_FROM_DEVICE); - - iser_dto_add_regd_buff(recv_dto, regd_data, 0, 0); - - err = iser_post_recv(rx_desc); - if (!err) - return 0; - - /* iser_post_recv failed */ - iser_dto_buffs_release(recv_dto); - kfree(rx_desc->data); -post_rx_kmalloc_failure: - kmem_cache_free(ig.desc_cache, rx_desc); - return err; -} - /* creates a new tx descriptor and adds header regd buffer */ static void iser_create_send_desc(struct iscsi_iser_conn *iser_conn, struct iser_desc *tx_desc) @@ -254,7 +179,7 @@ static void iser_create_send_desc(struct iscsi_iser_conn *iser_conn, memset(regd_hdr, 0, sizeof(struct iser_regd_buf)); regd_hdr->device = iser_conn->ib_conn->device; regd_hdr->virt_addr = tx_desc; /* == &tx_desc->iser_header */ - regd_hdr->data_size = ISER_TOTAL_HEADERS_LEN; + regd_hdr->data_size = ISER_HEADERS_LEN; send_dto->ib_conn = iser_conn->ib_conn; send_dto->notify_enable = 1; @@ -266,6 +191,72 @@ static void iser_create_send_desc(struct iscsi_iser_conn *iser_conn, iser_dto_add_regd_buff(send_dto, regd_hdr, 0, 0); } +int iser_alloc_rx_descriptors(struct iser_conn *ib_conn) +{ + int i, j; + u64 dma_addr; + struct iser_rx_desc *rx_desc; + struct ib_sge *rx_sg; + struct iser_device *device = ib_conn->device; + + ib_conn->rx_descs = kmalloc(ISER_QP_MAX_RECV_DTOS * + sizeof(struct iser_rx_desc), GFP_KERNEL); + if (!ib_conn->rx_descs) + goto rx_desc_alloc_fail; + + rx_desc = ib_conn->rx_descs; + + for (i = 0; i < ISER_QP_MAX_RECV_DTOS; i++, rx_desc++) { + dma_addr = ib_dma_map_single(device->ib_device, (void *)rx_desc, + ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE); + if (ib_dma_mapping_error(device->ib_device, dma_addr)) + goto rx_desc_dma_map_failed; + + rx_desc->dma_addr = dma_addr; + + rx_sg = &rx_desc->rx_sg; + rx_sg->addr = rx_desc->dma_addr; + rx_sg->length = ISER_RX_PAYLOAD_SIZE; + rx_sg->lkey = device->mr->lkey; + } + + ib_conn->rx_desc_head = 0; + return 0; + +rx_desc_dma_map_failed: + rx_desc = ib_conn->rx_descs; + for (j = 0; j < i; j++, rx_desc++) + ib_dma_unmap_single(device->ib_device, rx_desc->dma_addr, + ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE); + kfree(ib_conn->rx_descs); + ib_conn->rx_descs = NULL; +rx_desc_alloc_fail: + iser_err("failed allocating rx descriptors / data buffers\n"); + return -ENOMEM; +} + +void iser_free_rx_descriptors(struct iser_conn *ib_conn) +{ + int i; + struct iser_rx_desc *rx_desc; + struct iser_device *device = ib_conn->device; + + if (ib_conn->login_buf) { + ib_dma_unmap_single(device->ib_device, ib_conn->login_dma, + ISER_RX_LOGIN_SIZE, DMA_FROM_DEVICE); + kfree(ib_conn->login_buf); + } + + if (!ib_conn->rx_descs) + return; + + rx_desc = ib_conn->rx_descs; + for (i = 0; i < ISER_QP_MAX_RECV_DTOS; i++, rx_desc++) + ib_dma_unmap_single(device->ib_device, rx_desc->dma_addr, + ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE); + kfree(ib_conn->rx_descs); +} + /** * iser_conn_set_full_featured_mode - (iSER API) */ @@ -273,27 +264,20 @@ int iser_conn_set_full_featured_mode(struct iscsi_conn *conn) { struct iscsi_iser_conn *iser_conn = conn->dd_data; - int i; - /* no need to keep it in a var, we are after login so if this should - * be negotiated, by now the result should be available here */ - int initial_post_recv_bufs_num = ISER_MAX_RX_MISC_PDUS; - - iser_dbg("Initially post: %d\n", initial_post_recv_bufs_num); + iser_dbg("Initially post: %d\n", ISER_MIN_POSTED_RX); /* Check that there is no posted recv or send buffers left - */ /* they must be consumed during the login phase */ BUG_ON(atomic_read(&iser_conn->ib_conn->post_recv_buf_count) != 0); BUG_ON(atomic_read(&iser_conn->ib_conn->post_send_buf_count) != 0); + if (iser_alloc_rx_descriptors(iser_conn->ib_conn)) + return -ENOMEM; + /* Initial post receive buffers */ - for (i = 0; i < initial_post_recv_bufs_num; i++) { - if (iser_post_receive_control(conn) != 0) { - iser_err("Failed to post recv bufs at:%d conn:0x%p\n", - i, conn); - return -ENOMEM; - } - } - iser_dbg("Posted %d post recv bufs, conn:0x%p\n", i, conn); + if (iser_post_recvm(iser_conn->ib_conn, ISER_MIN_POSTED_RX)) + return -ENOMEM; + return 0; } @@ -321,7 +305,7 @@ int iser_send_command(struct iscsi_conn *conn, struct iscsi_iser_task *iser_task = task->dd_data; struct iser_dto *send_dto = NULL; unsigned long edtl; - int err = 0; + int err; struct iser_data_buf *data_buf; struct iscsi_cmd *hdr = (struct iscsi_cmd *)task->hdr; struct scsi_cmnd *sc = task->sc; @@ -371,12 +355,6 @@ int iser_send_command(struct iscsi_conn *conn, iser_reg_single(iser_conn->ib_conn->device, send_dto->regd[0], DMA_TO_DEVICE); - if (iser_post_receive_control(conn) != 0) { - iser_err("post_recv failed!\n"); - err = -ENOMEM; - goto send_command_error; - } - iser_task->status = ISER_TASK_STATUS_STARTED; err = iser_post_send(&iser_task->desc); @@ -474,7 +452,7 @@ int iser_send_control(struct iscsi_conn *conn, struct iser_desc *mdesc = &iser_task->desc; struct iser_dto *send_dto = NULL; unsigned long data_seg_len; - int err = 0; + int err; struct iser_regd_buf *regd_buf; struct iser_device *device; @@ -511,10 +489,10 @@ int iser_send_control(struct iscsi_conn *conn, data_seg_len); } - if (iser_post_receive_control(conn) != 0) { - iser_err("post_rcv_buff failed!\n"); - err = -ENOMEM; - goto send_control_error; + if (task == conn->login_task) { + err = iser_post_recvl(iser_conn->ib_conn); + if (err) + goto send_control_error; } err = iser_post_send(mdesc); @@ -530,27 +508,34 @@ send_control_error: /** * iser_rcv_dto_completion - recv DTO completion */ -void iser_rcv_completion(struct iser_desc *rx_desc, - unsigned long dto_xfer_len) +void iser_rcv_completion(struct iser_rx_desc *rx_desc, + unsigned long rx_xfer_len, + struct iser_conn *ib_conn) { - struct iser_dto *dto = &rx_desc->dto; - struct iscsi_iser_conn *conn = dto->ib_conn->iser_conn; + struct iscsi_iser_conn *conn = ib_conn->iser_conn; struct iscsi_task *task; struct iscsi_iser_task *iser_task; struct iscsi_hdr *hdr; - char *rx_data = NULL; - int rx_data_len = 0; unsigned char opcode; + u64 rx_dma; + int rx_buflen, outstanding, count, err; + + /* differentiate between login to all other PDUs */ + if ((char *)rx_desc == ib_conn->login_buf) { + rx_dma = ib_conn->login_dma; + rx_buflen = ISER_RX_LOGIN_SIZE; + } else { + rx_dma = rx_desc->dma_addr; + rx_buflen = ISER_RX_PAYLOAD_SIZE; + } - hdr = &rx_desc->iscsi_header; + ib_dma_sync_single_for_cpu(ib_conn->device->ib_device, rx_dma, + rx_buflen, DMA_FROM_DEVICE); - iser_dbg("op 0x%x itt 0x%x\n", hdr->opcode,hdr->itt); + hdr = &rx_desc->iscsi_header; - if (dto_xfer_len > ISER_TOTAL_HEADERS_LEN) { /* we have data */ - rx_data_len = dto_xfer_len - ISER_TOTAL_HEADERS_LEN; - rx_data = dto->regd[1]->virt_addr; - rx_data += dto->offset[1]; - } + iser_dbg("op 0x%x itt 0x%x dlen %d\n", hdr->opcode, + hdr->itt, (int)(rx_xfer_len - ISER_HEADERS_LEN)); opcode = hdr->opcode & ISCSI_OPCODE_MASK; @@ -573,18 +558,30 @@ void iser_rcv_completion(struct iser_desc *rx_desc, iscsi_put_task(task); } } - iser_dto_buffs_release(dto); - iscsi_iser_recv(conn->iscsi_conn, hdr, rx_data, rx_data_len); + iscsi_iser_recv(conn->iscsi_conn, hdr, + rx_desc->data, rx_xfer_len - ISER_HEADERS_LEN); - kfree(rx_desc->data); - kmem_cache_free(ig.desc_cache, rx_desc); + ib_dma_sync_single_for_device(ib_conn->device->ib_device, rx_dma, + rx_buflen, 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 */ atomic_dec(&conn->ib_conn->post_recv_buf_count); + + if (rx_dma == ib_conn->login_dma) + return; + + outstanding = atomic_read(&ib_conn->post_recv_buf_count); + if (outstanding + ISER_MIN_POSTED_RX <= ISER_QP_MAX_RECV_DTOS) { + count = min(ISER_QP_MAX_RECV_DTOS - outstanding, + ISER_MIN_POSTED_RX); + err = iser_post_recvm(ib_conn, count); + if (err) + iser_err("posting %d rx bufs err %d\n", count, err); + } } void iser_snd_completion(struct iser_desc *tx_desc) -- cgit v1.1