From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Return-Path: Subject: Re: [PATCH 05/24] ibtrs: client: main functionality To: Roman Pen , linux-block@vger.kernel.org, linux-rdma@vger.kernel.org Cc: Jens Axboe , Christoph Hellwig , Bart Van Assche , Or Gerlitz , Danil Kipnis , Jack Wang References: <20180202140904.2017-1-roman.penyaev@profitbricks.com> <20180202140904.2017-6-roman.penyaev@profitbricks.com> From: Sagi Grimberg Message-ID: Date: Mon, 5 Feb 2018 13:19:43 +0200 MIME-Version: 1.0 In-Reply-To: <20180202140904.2017-6-roman.penyaev@profitbricks.com> Content-Type: text/plain; charset=utf-8; format=flowed List-ID: Hi Roman, > +static inline void ibtrs_clt_state_lock(void) > +{ > + rcu_read_lock(); > +} > + > +static inline void ibtrs_clt_state_unlock(void) > +{ > + rcu_read_unlock(); > +} This looks rather pointless... > + > +#define cmpxchg_min(var, new) ({ \ > + typeof(var) old; \ > + \ > + do { \ > + old = var; \ > + new = (!old ? new : min_t(typeof(var), old, new)); \ > + } while (cmpxchg(&var, old, new) != old); \ > +}) Why is this sort of thing local to your driver? > +/** > + * struct ibtrs_fr_pool - pool of fast registration descriptors > + * > + * An entry is available for allocation if and only if it occurs in @free_list. > + * > + * @size: Number of descriptors in this pool. > + * @max_page_list_len: Maximum fast registration work request page list length. > + * @lock: Protects free_list. > + * @free_list: List of free descriptors. > + * @desc: Fast registration descriptor pool. > + */ > +struct ibtrs_fr_pool { > + int size; > + int max_page_list_len; > + spinlock_t lock; /* protects free_list */ > + struct list_head free_list; > + struct ibtrs_fr_desc desc[0]; > +}; We already have a per-qp fr list implementation, any specific reason to implement it again? > +static inline struct ibtrs_tag * > +__ibtrs_get_tag(struct ibtrs_clt *clt, enum ibtrs_clt_con_type con_type) > +{ > + size_t max_depth = clt->queue_depth; > + struct ibtrs_tag *tag; > + int cpu, bit; > + > + cpu = get_cpu(); > + do { > + bit = find_first_zero_bit(clt->tags_map, max_depth); > + if (unlikely(bit >= max_depth)) { > + put_cpu(); > + return NULL; > + } > + > + } while (unlikely(test_and_set_bit_lock(bit, clt->tags_map))); > + put_cpu(); > + > + tag = GET_TAG(clt, bit); > + WARN_ON(tag->mem_id != bit); > + tag->cpu_id = cpu; > + tag->con_type = con_type; > + > + return tag; > +} > + > +static inline void __ibtrs_put_tag(struct ibtrs_clt *clt, > + struct ibtrs_tag *tag) > +{ > + clear_bit_unlock(tag->mem_id, clt->tags_map); > +} > + > +struct ibtrs_tag *ibtrs_clt_get_tag(struct ibtrs_clt *clt, > + enum ibtrs_clt_con_type con_type, > + int can_wait) > +{ > + struct ibtrs_tag *tag; > + DEFINE_WAIT(wait); > + > + tag = __ibtrs_get_tag(clt, con_type); > + if (likely(tag) || !can_wait) > + return tag; > + > + do { > + prepare_to_wait(&clt->tags_wait, &wait, TASK_UNINTERRUPTIBLE); > + tag = __ibtrs_get_tag(clt, con_type); > + if (likely(tag)) > + break; > + > + io_schedule(); > + } while (1); > + > + finish_wait(&clt->tags_wait, &wait); > + > + return tag; > +} > +EXPORT_SYMBOL(ibtrs_clt_get_tag); > + > +void ibtrs_clt_put_tag(struct ibtrs_clt *clt, struct ibtrs_tag *tag) > +{ > + if (WARN_ON(!test_bit(tag->mem_id, clt->tags_map))) > + return; > + > + __ibtrs_put_tag(clt, tag); > + > + /* > + * Putting a tag is a barrier, so we will observe > + * new entry in the wait list, no worries. > + */ > + if (waitqueue_active(&clt->tags_wait)) > + wake_up(&clt->tags_wait); > +} > +EXPORT_SYMBOL(ibtrs_clt_put_tag); Again, the tags are not clear why they are needed... > +/** > + * ibtrs_destroy_fr_pool() - free the resources owned by a pool > + * @pool: Fast registration pool to be destroyed. > + */ > +static void ibtrs_destroy_fr_pool(struct ibtrs_fr_pool *pool) > +{ > + struct ibtrs_fr_desc *d; > + int i, err; > + > + if (!pool) > + return; > + > + for (i = 0, d = &pool->desc[0]; i < pool->size; i++, d++) { > + if (d->mr) { > + err = ib_dereg_mr(d->mr); > + if (err) > + pr_err("Failed to deregister memory region," > + " err: %d\n", err); > + } > + } > + kfree(pool); > +} > + > +/** > + * ibtrs_create_fr_pool() - allocate and initialize a pool for fast registration > + * @device: IB device to allocate fast registration descriptors for. > + * @pd: Protection domain associated with the FR descriptors. > + * @pool_size: Number of descriptors to allocate. > + * @max_page_list_len: Maximum fast registration work request page list length. > + */ > +static struct ibtrs_fr_pool *ibtrs_create_fr_pool(struct ib_device *device, > + struct ib_pd *pd, > + int pool_size, > + int max_page_list_len) > +{ > + struct ibtrs_fr_pool *pool; > + struct ibtrs_fr_desc *d; > + struct ib_mr *mr; > + int i, ret; > + > + if (pool_size <= 0) { > + pr_warn("Creating fr pool failed, invalid pool size %d\n", > + pool_size); > + ret = -EINVAL; > + goto err; > + } > + > + pool = kzalloc(sizeof(*pool) + pool_size * sizeof(*d), GFP_KERNEL); > + if (!pool) { > + ret = -ENOMEM; > + goto err; > + } > + > + pool->size = pool_size; > + pool->max_page_list_len = max_page_list_len; > + spin_lock_init(&pool->lock); > + INIT_LIST_HEAD(&pool->free_list); > + > + for (i = 0, d = &pool->desc[0]; i < pool->size; i++, d++) { > + mr = ib_alloc_mr(pd, IB_MR_TYPE_MEM_REG, max_page_list_len); > + if (IS_ERR(mr)) { > + pr_warn("Failed to allocate fast region memory\n"); > + ret = PTR_ERR(mr); > + goto destroy_pool; > + } > + d->mr = mr; > + list_add_tail(&d->entry, &pool->free_list); > + } > + > + return pool; > + > +destroy_pool: > + ibtrs_destroy_fr_pool(pool); > +err: > + return ERR_PTR(ret); > +} > + > +/** > + * ibtrs_fr_pool_get() - obtain a descriptor suitable for fast registration > + * @pool: Pool to obtain descriptor from. > + */ > +static struct ibtrs_fr_desc *ibtrs_fr_pool_get(struct ibtrs_fr_pool *pool) > +{ > + struct ibtrs_fr_desc *d = NULL; > + > + spin_lock_bh(&pool->lock); > + if (!list_empty(&pool->free_list)) { > + d = list_first_entry(&pool->free_list, typeof(*d), entry); > + list_del(&d->entry); > + } > + spin_unlock_bh(&pool->lock); > + > + return d; > +} > + > +/** > + * ibtrs_fr_pool_put() - put an FR descriptor back in the free list > + * @pool: Pool the descriptor was allocated from. > + * @desc: Pointer to an array of fast registration descriptor pointers. > + * @n: Number of descriptors to put back. > + * > + * Note: The caller must already have queued an invalidation request for > + * desc->mr->rkey before calling this function. > + */ > +static void ibtrs_fr_pool_put(struct ibtrs_fr_pool *pool, > + struct ibtrs_fr_desc **desc, int n) > +{ > + int i; > + > + spin_lock_bh(&pool->lock); > + for (i = 0; i < n; i++) > + list_add(&desc[i]->entry, &pool->free_list); > + spin_unlock_bh(&pool->lock); > +} > + > +static void ibtrs_map_desc(struct ibtrs_map_state *state, dma_addr_t dma_addr, > + u32 dma_len, u32 rkey, u32 max_desc) > +{ > + struct ibtrs_sg_desc *desc = state->desc; > + > + pr_debug("dma_addr %llu, key %u, dma_len %u\n", > + dma_addr, rkey, dma_len); > + desc->addr = cpu_to_le64(dma_addr); > + desc->key = cpu_to_le32(rkey); > + desc->len = cpu_to_le32(dma_len); > + > + state->total_len += dma_len; > + if (state->ndesc < max_desc) { > + state->desc++; > + state->ndesc++; > + } else { > + state->ndesc = INT_MIN; > + pr_err("Could not fit S/G list into buffer descriptor %d.\n", > + max_desc); > + } > +} > + > +static int ibtrs_map_finish_fmr(struct ibtrs_map_state *state, > + struct ibtrs_clt_con *con) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + struct ib_pool_fmr *fmr; > + dma_addr_t dma_addr; > + u64 io_addr = 0; > + > + fmr = ib_fmr_pool_map_phys(sess->fmr_pool, state->pages, > + state->npages, io_addr); > + if (IS_ERR(fmr)) { > + ibtrs_wrn_rl(sess, "Failed to map FMR from FMR pool, " > + "err: %ld\n", PTR_ERR(fmr)); > + return PTR_ERR(fmr); > + } > + > + *state->next_fmr++ = fmr; > + state->nmdesc++; > + dma_addr = state->base_dma_addr & ~sess->mr_page_mask; > + pr_debug("ndesc = %d, nmdesc = %d, npages = %d\n", > + state->ndesc, state->nmdesc, state->npages); > + if (state->dir == DMA_TO_DEVICE) > + ibtrs_map_desc(state, dma_addr, state->dma_len, fmr->fmr->lkey, > + sess->max_desc); > + else > + ibtrs_map_desc(state, dma_addr, state->dma_len, fmr->fmr->rkey, > + sess->max_desc); > + > + return 0; > +} > + > +static void ibtrs_clt_fast_reg_done(struct ib_cq *cq, struct ib_wc *wc) > +{ > + struct ibtrs_clt_con *con = cq->cq_context; > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + > + if (unlikely(wc->status != IB_WC_SUCCESS)) { > + ibtrs_err(sess, "Failed IB_WR_REG_MR: %s\n", > + ib_wc_status_msg(wc->status)); > + ibtrs_rdma_error_recovery(con); > + } > +} > + > +static struct ib_cqe fast_reg_cqe = { > + .done = ibtrs_clt_fast_reg_done > +}; > + > +/* TODO */ > +static int ibtrs_map_finish_fr(struct ibtrs_map_state *state, > + struct ibtrs_clt_con *con, int sg_cnt, > + unsigned int *sg_offset_p) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + struct ibtrs_fr_desc *desc; > + struct ib_send_wr *bad_wr; > + struct ib_reg_wr wr; > + struct ib_pd *pd; > + u32 rkey; > + int n; > + > + pd = sess->s.ib_dev->pd; > + if (sg_cnt == 1 && (pd->flags & IB_PD_UNSAFE_GLOBAL_RKEY)) { > + unsigned int sg_offset = sg_offset_p ? *sg_offset_p : 0; > + > + ibtrs_map_desc(state, sg_dma_address(state->sg) + sg_offset, > + sg_dma_len(state->sg) - sg_offset, > + pd->unsafe_global_rkey, sess->max_desc); > + if (sg_offset_p) > + *sg_offset_p = 0; > + return 1; > + } > + > + desc = ibtrs_fr_pool_get(con->fr_pool); > + if (!desc) { > + ibtrs_wrn_rl(sess, "Failed to get descriptor from FR pool\n"); > + return -ENOMEM; > + } > + > + rkey = ib_inc_rkey(desc->mr->rkey); > + ib_update_fast_reg_key(desc->mr, rkey); > + > + memset(&wr, 0, sizeof(wr)); > + n = ib_map_mr_sg(desc->mr, state->sg, sg_cnt, sg_offset_p, > + sess->mr_page_size); > + if (unlikely(n < 0)) { > + ibtrs_fr_pool_put(con->fr_pool, &desc, 1); > + return n; > + } > + > + wr.wr.next = NULL; > + wr.wr.opcode = IB_WR_REG_MR; > + wr.wr.wr_cqe = &fast_reg_cqe; > + wr.wr.num_sge = 0; > + wr.wr.send_flags = 0; > + wr.mr = desc->mr; > + wr.key = desc->mr->rkey; > + wr.access = (IB_ACCESS_LOCAL_WRITE | IB_ACCESS_REMOTE_WRITE); Do you actually ever have remote write access in your protocol? > +static void ibtrs_clt_inv_rkey_done(struct ib_cq *cq, struct ib_wc *wc) > +{ > + struct ibtrs_clt_con *con = cq->cq_context; > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + > + if (unlikely(wc->status != IB_WC_SUCCESS)) { > + ibtrs_err(sess, "Failed IB_WR_LOCAL_INV: %s\n", > + ib_wc_status_msg(wc->status)); > + ibtrs_rdma_error_recovery(con); > + } > +} > + > +static struct ib_cqe local_inv_cqe = { > + .done = ibtrs_clt_inv_rkey_done > +}; > + > +static int ibtrs_inv_rkey(struct ibtrs_clt_con *con, u32 rkey) > +{ > + struct ib_send_wr *bad_wr; > + struct ib_send_wr wr = { > + .opcode = IB_WR_LOCAL_INV, > + .wr_cqe = &local_inv_cqe, > + .next = NULL, > + .num_sge = 0, > + .send_flags = 0, > + .ex.invalidate_rkey = rkey, > + }; > + > + return ib_post_send(con->c.qp, &wr, &bad_wr); > +} Is not signalling the local invalidate safe? A recent report suggested that this is not safe in the presence of ack drops. > +static int ibtrs_post_send_rdma(struct ibtrs_clt_con *con, > + struct ibtrs_clt_io_req *req, > + u64 addr, u32 off, u32 imm) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + enum ib_send_flags flags; > + struct ib_sge list[1]; > + > + if (unlikely(!req->sg_size)) { > + ibtrs_wrn(sess, "Doing RDMA Write failed, no data supplied\n"); > + return -EINVAL; > + } > + > + /* user data and user message in the first list element */ > + list[0].addr = req->iu->dma_addr; > + list[0].length = req->sg_size; > + list[0].lkey = sess->s.ib_dev->lkey; > + > + /* > + * From time to time we have to post signalled sends, > + * or send queue will fill up and only QP reset can help. > + */ > + flags = atomic_inc_return(&con->io_cnt) % sess->queue_depth ? > + 0 : IB_SEND_SIGNALED; > + return ibtrs_iu_post_rdma_write_imm(&con->c, req->iu, list, 1, > + sess->srv_rdma_buf_rkey, > + addr + off, imm, flags); > +} > + > +static void ibtrs_set_sge_with_desc(struct ib_sge *list, > + struct ibtrs_sg_desc *desc) > +{ > + list->addr = le64_to_cpu(desc->addr); > + list->length = le32_to_cpu(desc->len); > + list->lkey = le32_to_cpu(desc->key); > + pr_debug("dma_addr %llu, key %u, dma_len %u\n", > + list->addr, list->lkey, list->length); > +} > + > +static void ibtrs_set_rdma_desc_last(struct ibtrs_clt_con *con, > + struct ib_sge *list, > + struct ibtrs_clt_io_req *req, > + struct ib_rdma_wr *wr, int offset, > + struct ibtrs_sg_desc *desc, int m, > + int n, u64 addr, u32 size, u32 imm) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + enum ib_send_flags flags; > + int i; > + > + for (i = m; i < n; i++, desc++) > + ibtrs_set_sge_with_desc(&list[i], desc); > + > + list[i].addr = req->iu->dma_addr; > + list[i].length = size; > + list[i].lkey = sess->s.ib_dev->lkey; > + > + wr->wr.wr_cqe = &req->iu->cqe; > + wr->wr.sg_list = &list[m]; > + wr->wr.num_sge = n - m + 1; > + wr->remote_addr = addr + offset; > + wr->rkey = sess->srv_rdma_buf_rkey; > + > + /* > + * From time to time we have to post signalled sends, > + * or send queue will fill up and only QP reset can help. > + */ > + flags = atomic_inc_return(&con->io_cnt) % sess->queue_depth ? > + 0 : IB_SEND_SIGNALED; > + > + wr->wr.opcode = IB_WR_RDMA_WRITE_WITH_IMM; > + wr->wr.send_flags = flags; > + wr->wr.ex.imm_data = cpu_to_be32(imm); > +} > + > +static int ibtrs_post_send_rdma_desc_more(struct ibtrs_clt_con *con, > + struct ib_sge *list, > + struct ibtrs_clt_io_req *req, > + struct ibtrs_sg_desc *desc, int n, > + u64 addr, u32 size, u32 imm) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + size_t max_sge, num_sge, num_wr; > + struct ib_send_wr *bad_wr; > + struct ib_rdma_wr *wrs, *wr; > + int j = 0, k, offset = 0, len = 0; > + int m = 0; > + int ret; > + > + max_sge = sess->max_sge; > + num_sge = 1 + n; > + num_wr = DIV_ROUND_UP(num_sge, max_sge); > + > + wrs = kcalloc(num_wr, sizeof(*wrs), GFP_ATOMIC); > + if (!wrs) > + return -ENOMEM; > + > + if (num_wr == 1) > + goto last_one; > + > + for (; j < num_wr; j++) { > + wr = &wrs[j]; > + for (k = 0; k < max_sge; k++, desc++) { > + m = k + j * max_sge; > + ibtrs_set_sge_with_desc(&list[m], desc); > + len += le32_to_cpu(desc->len); > + } > + wr->wr.wr_cqe = &req->iu->cqe; > + wr->wr.sg_list = &list[m]; > + wr->wr.num_sge = max_sge; > + wr->remote_addr = addr + offset; > + wr->rkey = sess->srv_rdma_buf_rkey; > + > + offset += len; > + wr->wr.next = &wrs[j + 1].wr; > + wr->wr.opcode = IB_WR_RDMA_WRITE; > + } > + > +last_one: > + wr = &wrs[j]; > + > + ibtrs_set_rdma_desc_last(con, list, req, wr, offset, > + desc, m, n, addr, size, imm); > + > + ret = ib_post_send(con->c.qp, &wrs[0].wr, &bad_wr); > + if (unlikely(ret)) > + ibtrs_err(sess, "Posting write request to QP failed," > + " err: %d\n", ret); > + kfree(wrs); > + return ret; > +} > + > +static int ibtrs_post_send_rdma_desc(struct ibtrs_clt_con *con, > + struct ibtrs_clt_io_req *req, > + struct ibtrs_sg_desc *desc, int n, > + u64 addr, u32 size, u32 imm) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + enum ib_send_flags flags; > + struct ib_sge *list; > + size_t num_sge; > + int ret, i; > + > + num_sge = 1 + n; > + list = kmalloc_array(num_sge, sizeof(*list), GFP_ATOMIC); > + if (!list) > + return -ENOMEM; > + > + if (num_sge < sess->max_sge) { > + for (i = 0; i < n; i++, desc++) > + ibtrs_set_sge_with_desc(&list[i], desc); > + list[i].addr = req->iu->dma_addr; > + list[i].length = size; > + list[i].lkey = sess->s.ib_dev->lkey; > + > + /* > + * From time to time we have to post signalled sends, > + * or send queue will fill up and only QP reset can help. > + */ > + flags = atomic_inc_return(&con->io_cnt) % sess->queue_depth ? > + 0 : IB_SEND_SIGNALED; > + ret = ibtrs_iu_post_rdma_write_imm(&con->c, req->iu, list, > + num_sge, > + sess->srv_rdma_buf_rkey, > + addr, imm, flags); > + } else { > + ret = ibtrs_post_send_rdma_desc_more(con, list, req, desc, n, > + addr, size, imm); > + } > + > + kfree(list); > + return ret; > +} > + > +static int ibtrs_post_send_rdma_more(struct ibtrs_clt_con *con, > + struct ibtrs_clt_io_req *req, > + u64 addr, u32 size, u32 imm) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + struct ib_device *ibdev = sess->s.ib_dev->dev; > + enum ib_send_flags flags; > + struct scatterlist *sg; > + struct ib_sge *list; > + size_t num_sge; > + int i, ret; > + > + num_sge = 1 + req->sg_cnt; > + list = kmalloc_array(num_sge, sizeof(*list), GFP_ATOMIC); > + if (!list) > + return -ENOMEM; > + > + for_each_sg(req->sglist, sg, req->sg_cnt, i) { > + list[i].addr = ib_sg_dma_address(ibdev, sg); > + list[i].length = ib_sg_dma_len(ibdev, sg); > + list[i].lkey = sess->s.ib_dev->lkey; > + } > + list[i].addr = req->iu->dma_addr; > + list[i].length = size; > + list[i].lkey = sess->s.ib_dev->lkey; > + > + /* > + * From time to time we have to post signalled sends, > + * or send queue will fill up and only QP reset can help. > + */ > + flags = atomic_inc_return(&con->io_cnt) % sess->queue_depth ? > + 0 : IB_SEND_SIGNALED; > + ret = ibtrs_iu_post_rdma_write_imm(&con->c, req->iu, list, num_sge, > + sess->srv_rdma_buf_rkey, > + addr, imm, flags); > + kfree(list); > + > + return ret; > +} All these rdma halpers looks like that can be reused from the rdma rw API if it was enhanced with immediate capabilities. > +static inline unsigned long ibtrs_clt_get_raw_ms(void) > +{ > + struct timespec ts; > + > + getrawmonotonic(&ts); > + > + return timespec_to_ns(&ts) / NSEC_PER_MSEC; > +} Why is this local to your driver? > + > +static void complete_rdma_req(struct ibtrs_clt_io_req *req, > + int errno, bool notify) > +{ > + struct ibtrs_clt_con *con = req->con; > + struct ibtrs_clt_sess *sess; > + enum dma_data_direction dir; > + struct ibtrs_clt *clt; > + void *priv; > + > + if (WARN_ON(!req->in_use)) > + return; > + if (WARN_ON(!req->con)) > + return; > + sess = to_clt_sess(con->c.sess); > + clt = sess->clt; > + > + if (req->sg_cnt > fmr_sg_cnt) > + ibtrs_unmap_fast_reg_data(req->con, req); > + if (req->sg_cnt) > + ib_dma_unmap_sg(sess->s.ib_dev->dev, req->sglist, > + req->sg_cnt, req->dir); > + if (sess->stats.enable_rdma_lat) > + ibtrs_clt_update_rdma_lat(&sess->stats, > + req->dir == DMA_FROM_DEVICE, > + ibtrs_clt_get_raw_ms() - > + req->start_time); > + ibtrs_clt_decrease_inflight(&sess->stats); > + > + req->in_use = false; > + req->con = NULL; > + priv = req->priv; > + dir = req->dir; > + > + if (notify) > + req->conf(priv, errno); > +} > + > +static void process_io_rsp(struct ibtrs_clt_sess *sess, u32 msg_id, s16 errno) > +{ > + if (WARN_ON(msg_id >= sess->queue_depth)) > + return; > + > + complete_rdma_req(&sess->reqs[msg_id], errno, true); > +} > + > +static struct ib_cqe io_comp_cqe = { > + .done = ibtrs_clt_rdma_done > +}; > + > +static void ibtrs_clt_rdma_done(struct ib_cq *cq, struct ib_wc *wc) > +{ > + struct ibtrs_clt_con *con = cq->cq_context; > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + u32 imm_type, imm_payload; > + int err; > + > + if (unlikely(wc->status != IB_WC_SUCCESS)) { > + if (wc->status != IB_WC_WR_FLUSH_ERR) { > + ibtrs_err(sess, "RDMA failed: %s\n", > + ib_wc_status_msg(wc->status)); > + ibtrs_rdma_error_recovery(con); > + } > + return; > + } > + ibtrs_clt_update_wc_stats(con); > + > + switch (wc->opcode) { > + case IB_WC_RDMA_WRITE: > + /* > + * post_send() RDMA write completions of IO reqs (read/write) > + * and hb > + */ > + break; > + case IB_WC_RECV_RDMA_WITH_IMM: > + /* > + * post_recv() RDMA write completions of IO reqs (read/write) > + * and hb > + */ > + if (WARN_ON(wc->wr_cqe != &io_comp_cqe)) > + return; > + err = ibtrs_post_recv_empty(&con->c, &io_comp_cqe); > + if (unlikely(err)) { > + ibtrs_err(sess, "ibtrs_post_recv_empty(): %d\n", err); > + ibtrs_rdma_error_recovery(con); > + break; > + } > + ibtrs_from_imm(be32_to_cpu(wc->ex.imm_data), > + &imm_type, &imm_payload); > + if (likely(imm_type == IBTRS_IO_RSP_IMM)) { > + u32 msg_id; > + > + ibtrs_from_io_rsp_imm(imm_payload, &msg_id, &err); > + process_io_rsp(sess, msg_id, err); > + } else if (imm_type == IBTRS_HB_MSG_IMM) { > + WARN_ON(con->c.cid); > + ibtrs_send_hb_ack(&sess->s); > + } else if (imm_type == IBTRS_HB_ACK_IMM) { > + WARN_ON(con->c.cid); > + sess->s.hb_missed_cnt = 0; > + } else { > + ibtrs_wrn(sess, "Unknown IMM type %u\n", imm_type); > + } > + break; > + default: > + ibtrs_wrn(sess, "Unexpected WC type: %s\n", > + ib_wc_opcode_str(wc->opcode)); > + return; > + } Is there a spec somewhere with the protocol information that explains how this all works? > +struct path_it { > + int i; > + struct list_head skip_list; > + struct ibtrs_clt *clt; > + struct ibtrs_clt_sess *(*next_path)(struct path_it *); > +}; > + > +#define do_each_path(path, clt, it) { \ > + path_it_init(it, clt); \ > + ibtrs_clt_state_lock(); \ > + for ((it)->i = 0; ((path) = ((it)->next_path)(it)) && \ > + (it)->i < (it)->clt->paths_num; \ > + (it)->i++) > + > +#define while_each_path(it) \ > + path_it_deinit(it); \ > + ibtrs_clt_state_unlock(); \ > + } > + > +/** > + * get_next_path_rr() - Returns path in round-robin fashion. > + * > + * Related to @MP_POLICY_RR > + * > + * Locks: > + * ibtrs_clt_state_lock() must be hold. > + */ > +static struct ibtrs_clt_sess *get_next_path_rr(struct path_it *it) > +{ > + struct ibtrs_clt_sess __percpu * __rcu *ppcpu_path, *path; > + struct ibtrs_clt *clt = it->clt; > + > + ppcpu_path = this_cpu_ptr(clt->pcpu_path); > + path = rcu_dereference(*ppcpu_path); > + if (unlikely(!path)) > + path = list_first_or_null_rcu(&clt->paths_list, > + typeof(*path), s.entry); > + else > + path = list_next_or_null_rcu_rr(path, &clt->paths_list, > + s.entry); > + rcu_assign_pointer(*ppcpu_path, path); > + > + return path; > +} > + > +/** > + * get_next_path_min_inflight() - Returns path with minimal inflight count. > + * > + * Related to @MP_POLICY_MIN_INFLIGHT > + * > + * Locks: > + * ibtrs_clt_state_lock() must be hold. > + */ > +static struct ibtrs_clt_sess *get_next_path_min_inflight(struct path_it *it) > +{ > + struct ibtrs_clt_sess *min_path = NULL; > + struct ibtrs_clt *clt = it->clt; > + struct ibtrs_clt_sess *sess; > + int min_inflight = INT_MAX; > + int inflight; > + > + list_for_each_entry_rcu(sess, &clt->paths_list, s.entry) { > + if (unlikely(!list_empty(raw_cpu_ptr(sess->mp_skip_entry)))) > + continue; > + > + inflight = atomic_read(&sess->stats.inflight); > + > + if (inflight < min_inflight) { > + min_inflight = inflight; > + min_path = sess; > + } > + } > + > + /* > + * add the path to the skip list, so that next time we can get > + * a different one > + */ > + if (min_path) > + list_add(raw_cpu_ptr(min_path->mp_skip_entry), &it->skip_list); > + > + return min_path; > +} > + > +static inline void path_it_init(struct path_it *it, struct ibtrs_clt *clt) > +{ > + INIT_LIST_HEAD(&it->skip_list); > + it->clt = clt; > + it->i = 0; > + > + if (clt->mp_policy == MP_POLICY_RR) > + it->next_path = get_next_path_rr; > + else > + it->next_path = get_next_path_min_inflight; > +} > + > +static inline void path_it_deinit(struct path_it *it) > +{ > + struct list_head *skip, *tmp; > + /* > + * The skip_list is used only for the MIN_INFLIGHT policy. > + * We need to remove paths from it, so that next IO can insert > + * paths (->mp_skip_entry) into a skip_list again. > + */ > + list_for_each_safe(skip, tmp, &it->skip_list) > + list_del_init(skip); > +} > + > +static inline void ibtrs_clt_init_req(struct ibtrs_clt_io_req *req, > + struct ibtrs_clt_sess *sess, > + ibtrs_conf_fn *conf, > + struct ibtrs_tag *tag, void *priv, > + const struct kvec *vec, size_t usr_len, > + struct scatterlist *sg, size_t sg_cnt, > + size_t data_len, int dir) > +{ > + req->tag = tag; > + req->in_use = true; > + req->usr_len = usr_len; > + req->data_len = data_len; > + req->sglist = sg; > + req->sg_cnt = sg_cnt; > + req->priv = priv; > + req->dir = dir; > + req->con = ibtrs_tag_to_clt_con(sess, tag); > + req->conf = conf; > + copy_from_kvec(req->iu->buf, vec, usr_len); > + if (sess->stats.enable_rdma_lat) > + req->start_time = ibtrs_clt_get_raw_ms(); > +} > + > +static inline struct ibtrs_clt_io_req * > +ibtrs_clt_get_req(struct ibtrs_clt_sess *sess, ibtrs_conf_fn *conf, > + struct ibtrs_tag *tag, void *priv, > + const struct kvec *vec, size_t usr_len, > + struct scatterlist *sg, size_t sg_cnt, > + size_t data_len, int dir) > +{ > + struct ibtrs_clt_io_req *req; > + > + req = &sess->reqs[tag->mem_id]; > + ibtrs_clt_init_req(req, sess, conf, tag, priv, vec, usr_len, > + sg, sg_cnt, data_len, dir); > + return req; > +} > + > +static inline struct ibtrs_clt_io_req * > +ibtrs_clt_get_copy_req(struct ibtrs_clt_sess *alive_sess, > + struct ibtrs_clt_io_req *fail_req) > +{ > + struct ibtrs_clt_io_req *req; > + struct kvec vec = { > + .iov_base = fail_req->iu->buf, > + .iov_len = fail_req->usr_len > + }; > + > + req = &alive_sess->reqs[fail_req->tag->mem_id]; > + ibtrs_clt_init_req(req, alive_sess, fail_req->conf, fail_req->tag, > + fail_req->priv, &vec, fail_req->usr_len, > + fail_req->sglist, fail_req->sg_cnt, > + fail_req->data_len, fail_req->dir); > + return req; > +} > + > +static int ibtrs_clt_write_req(struct ibtrs_clt_io_req *req); > +static int ibtrs_clt_read_req(struct ibtrs_clt_io_req *req); > + > +static int ibtrs_clt_failover_req(struct ibtrs_clt *clt, > + struct ibtrs_clt_io_req *fail_req) > +{ > + struct ibtrs_clt_sess *alive_sess; > + struct ibtrs_clt_io_req *req; > + int err = -ECONNABORTED; > + struct path_it it; > + > + do_each_path(alive_sess, clt, &it) { > + if (unlikely(alive_sess->state != IBTRS_CLT_CONNECTED)) > + continue; > + req = ibtrs_clt_get_copy_req(alive_sess, fail_req); > + if (req->dir == DMA_TO_DEVICE) > + err = ibtrs_clt_write_req(req); > + else > + err = ibtrs_clt_read_req(req); > + if (unlikely(err)) { > + req->in_use = false; > + continue; > + } > + /* Success path */ > + ibtrs_clt_inc_failover_cnt(&alive_sess->stats); > + break; > + } while_each_path(&it); > + > + return err; > +} > + > +static void fail_all_outstanding_reqs(struct ibtrs_clt_sess *sess, > + bool failover) > +{ > + struct ibtrs_clt *clt = sess->clt; > + struct ibtrs_clt_io_req *req; > + int i; > + > + if (!sess->reqs) > + return; > + for (i = 0; i < sess->queue_depth; ++i) { > + bool notify; > + int err = 0; > + > + req = &sess->reqs[i]; > + if (!req->in_use) > + continue; > + > + if (failover) > + err = ibtrs_clt_failover_req(clt, req); > + > + notify = (!failover || err); > + complete_rdma_req(req, -ECONNABORTED, notify); > + } > +} > + > +static void free_sess_reqs(struct ibtrs_clt_sess *sess) > +{ > + struct ibtrs_clt_io_req *req; > + int i; > + > + if (!sess->reqs) > + return; > + for (i = 0; i < sess->queue_depth; ++i) { > + req = &sess->reqs[i]; > + if (sess->fast_reg_mode == IBTRS_FAST_MEM_FR) > + kfree(req->fr_list); > + else if (sess->fast_reg_mode == IBTRS_FAST_MEM_FMR) > + kfree(req->fmr_list); > + kfree(req->map_page); > + ibtrs_iu_free(req->iu, DMA_TO_DEVICE, > + sess->s.ib_dev->dev); > + } > + kfree(sess->reqs); > + sess->reqs = NULL; > +} > + > +static int alloc_sess_reqs(struct ibtrs_clt_sess *sess) > +{ > + struct ibtrs_clt_io_req *req; > + void *mr_list; > + int i; > + > + sess->reqs = kcalloc(sess->queue_depth, sizeof(*sess->reqs), > + GFP_KERNEL); > + if (unlikely(!sess->reqs)) > + return -ENOMEM; > + > + for (i = 0; i < sess->queue_depth; ++i) { > + req = &sess->reqs[i]; > + req->iu = ibtrs_iu_alloc(i, sess->max_req_size, GFP_KERNEL, > + sess->s.ib_dev->dev, DMA_TO_DEVICE, > + ibtrs_clt_rdma_done); > + if (unlikely(!req->iu)) > + goto out; > + mr_list = kmalloc_array(sess->max_pages_per_mr, > + sizeof(void *), GFP_KERNEL); > + if (unlikely(!mr_list)) > + goto out; > + if (sess->fast_reg_mode == IBTRS_FAST_MEM_FR) > + req->fr_list = mr_list; > + else if (sess->fast_reg_mode == IBTRS_FAST_MEM_FMR) > + req->fmr_list = mr_list; > + > + req->map_page = kmalloc_array(sess->max_pages_per_mr, > + sizeof(void *), GFP_KERNEL); > + if (unlikely(!req->map_page)) > + goto out; > + } > + > + return 0; > + > +out: > + free_sess_reqs(sess); > + > + return -ENOMEM; > +} > + > +static int alloc_tags(struct ibtrs_clt *clt) > +{ > + unsigned int chunk_bits; > + int err, i; > + > + clt->tags_map = kcalloc(BITS_TO_LONGS(clt->queue_depth), sizeof(long), > + GFP_KERNEL); > + if (unlikely(!clt->tags_map)) { > + err = -ENOMEM; > + goto out_err; > + } > + clt->tags = kcalloc(clt->queue_depth, TAG_SIZE(clt), GFP_KERNEL); > + if (unlikely(!clt->tags)) { > + err = -ENOMEM; > + goto err_map; > + } > + chunk_bits = ilog2(clt->queue_depth - 1) + 1; > + for (i = 0; i < clt->queue_depth; i++) { > + struct ibtrs_tag *tag; > + > + tag = GET_TAG(clt, i); > + tag->mem_id = i; > + tag->mem_off = i << (MAX_IMM_PAYL_BITS - chunk_bits); > + } > + > + return 0; > + > +err_map: > + kfree(clt->tags_map); > + clt->tags_map = NULL; > +out_err: > + return err; > +} > + > +static void free_tags(struct ibtrs_clt *clt) > +{ > + kfree(clt->tags_map); > + clt->tags_map = NULL; > + kfree(clt->tags); > + clt->tags = NULL; > +} > + > +static void query_fast_reg_mode(struct ibtrs_clt_sess *sess) > +{ > + struct ibtrs_ib_dev *ib_dev; > + u64 max_pages_per_mr; > + int mr_page_shift; > + > + ib_dev = sess->s.ib_dev; > + if (ib_dev->dev->alloc_fmr && ib_dev->dev->dealloc_fmr && > + ib_dev->dev->map_phys_fmr && ib_dev->dev->unmap_fmr) { > + sess->fast_reg_mode = IBTRS_FAST_MEM_FMR; > + ibtrs_info(sess, "Device %s supports FMR\n", ib_dev->dev->name); > + } > + if (ib_dev->attrs.device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS && > + use_fr) { > + sess->fast_reg_mode = IBTRS_FAST_MEM_FR; > + ibtrs_info(sess, "Device %s supports FR\n", ib_dev->dev->name); > + } > + > + /* > + * Use the smallest page size supported by the HCA, down to a > + * minimum of 4096 bytes. We're unlikely to build large sglists > + * out of smaller entries. > + */ > + mr_page_shift = max(12, ffs(ib_dev->attrs.page_size_cap) - 1); > + sess->mr_page_size = 1 << mr_page_shift; > + sess->max_sge = ib_dev->attrs.max_sge; > + sess->mr_page_mask = ~((u64)sess->mr_page_size - 1); > + max_pages_per_mr = ib_dev->attrs.max_mr_size; > + do_div(max_pages_per_mr, sess->mr_page_size); > + sess->max_pages_per_mr = min_t(u64, sess->max_pages_per_mr, > + max_pages_per_mr); > + if (sess->fast_reg_mode == IBTRS_FAST_MEM_FR) { > + sess->max_pages_per_mr = > + min_t(u32, sess->max_pages_per_mr, > + ib_dev->attrs.max_fast_reg_page_list_len); > + } > + sess->mr_max_size = sess->mr_page_size * sess->max_pages_per_mr; > +} > + > +static int alloc_con_fast_pool(struct ibtrs_clt_con *con) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + struct ibtrs_fr_pool *fr_pool; > + int err = 0; > + > + if (sess->fast_reg_mode == IBTRS_FAST_MEM_FR) { > + fr_pool = ibtrs_create_fr_pool(sess->s.ib_dev->dev, > + sess->s.ib_dev->pd, > + sess->queue_depth, > + sess->max_pages_per_mr); > + if (unlikely(IS_ERR(fr_pool))) { > + err = PTR_ERR(fr_pool); > + ibtrs_err(sess, "FR pool allocation failed, err: %d\n", > + err); > + return err; > + } > + con->fr_pool = fr_pool; > + } > + > + return err; > +} > + > +static void free_con_fast_pool(struct ibtrs_clt_con *con) > +{ > + if (con->fr_pool) { > + ibtrs_destroy_fr_pool(con->fr_pool); > + con->fr_pool = NULL; > + } > +} > + > +static int alloc_sess_fast_pool(struct ibtrs_clt_sess *sess) > +{ > + struct ib_fmr_pool_param fmr_param; > + struct ib_fmr_pool *fmr_pool; > + int err = 0; > + > + if (sess->fast_reg_mode == IBTRS_FAST_MEM_FMR) { > + memset(&fmr_param, 0, sizeof(fmr_param)); > + fmr_param.pool_size = sess->queue_depth * > + sess->max_pages_per_mr; > + fmr_param.dirty_watermark = fmr_param.pool_size / 4; > + fmr_param.cache = 0; > + fmr_param.max_pages_per_fmr = sess->max_pages_per_mr; > + fmr_param.page_shift = ilog2(sess->mr_page_size); > + fmr_param.access = (IB_ACCESS_LOCAL_WRITE | > + IB_ACCESS_REMOTE_WRITE); > + > + fmr_pool = ib_create_fmr_pool(sess->s.ib_dev->pd, &fmr_param); > + if (unlikely(IS_ERR(fmr_pool))) { > + err = PTR_ERR(fmr_pool); > + ibtrs_err(sess, "FMR pool allocation failed, err: %d\n", > + err); > + return err; > + } > + sess->fmr_pool = fmr_pool; > + } > + > + return err; > +} > + > +static void free_sess_fast_pool(struct ibtrs_clt_sess *sess) > +{ > + if (sess->fmr_pool) { > + ib_destroy_fmr_pool(sess->fmr_pool); > + sess->fmr_pool = NULL; > + } > +} > + > +static int alloc_sess_io_bufs(struct ibtrs_clt_sess *sess) > +{ > + int ret; > + > + ret = alloc_sess_reqs(sess); > + if (unlikely(ret)) { > + ibtrs_err(sess, "alloc_sess_reqs(), err: %d\n", ret); > + return ret; > + } > + ret = alloc_sess_fast_pool(sess); > + if (unlikely(ret)) { > + ibtrs_err(sess, "alloc_sess_fast_pool(), err: %d\n", ret); > + goto free_reqs; > + } > + > + return 0; > + > +free_reqs: > + free_sess_reqs(sess); > + > + return ret; > +} > + > +static void free_sess_io_bufs(struct ibtrs_clt_sess *sess) > +{ > + free_sess_reqs(sess); > + free_sess_fast_pool(sess); > +} > + > +static bool __ibtrs_clt_change_state(struct ibtrs_clt_sess *sess, > + enum ibtrs_clt_state new_state) > +{ > + enum ibtrs_clt_state old_state; > + bool changed = false; > + > + old_state = sess->state; > + switch (new_state) { > + case IBTRS_CLT_CONNECTING: > + switch (old_state) { > + case IBTRS_CLT_RECONNECTING: > + changed = true; > + /* FALLTHRU */ > + default: > + break; > + } > + break; > + case IBTRS_CLT_RECONNECTING: > + switch (old_state) { > + case IBTRS_CLT_CONNECTED: > + case IBTRS_CLT_CONNECTING_ERR: > + case IBTRS_CLT_CLOSED: > + changed = true; > + /* FALLTHRU */ > + default: > + break; > + } > + break; > + case IBTRS_CLT_CONNECTED: > + switch (old_state) { > + case IBTRS_CLT_CONNECTING: > + changed = true; > + /* FALLTHRU */ > + default: > + break; > + } > + break; > + case IBTRS_CLT_CONNECTING_ERR: > + switch (old_state) { > + case IBTRS_CLT_CONNECTING: > + changed = true; > + /* FALLTHRU */ > + default: > + break; > + } > + break; > + case IBTRS_CLT_CLOSING: > + switch (old_state) { > + case IBTRS_CLT_CONNECTING: > + case IBTRS_CLT_CONNECTING_ERR: > + case IBTRS_CLT_RECONNECTING: > + case IBTRS_CLT_CONNECTED: > + changed = true; > + /* FALLTHRU */ > + default: > + break; > + } > + break; > + case IBTRS_CLT_CLOSED: > + switch (old_state) { > + case IBTRS_CLT_CLOSING: > + changed = true; > + /* FALLTHRU */ > + default: > + break; > + } > + break; > + case IBTRS_CLT_DEAD: > + switch (old_state) { > + case IBTRS_CLT_CLOSED: > + changed = true; > + /* FALLTHRU */ > + default: > + break; > + } > + break; > + default: > + break; > + } > + if (changed) { > + sess->state = new_state; > + wake_up_locked(&sess->state_wq); > + } > + > + return changed; > +} > + > +static bool ibtrs_clt_change_state_from_to(struct ibtrs_clt_sess *sess, > + enum ibtrs_clt_state old_state, > + enum ibtrs_clt_state new_state) > +{ > + bool changed = false; > + > + spin_lock_irq(&sess->state_wq.lock); > + if (sess->state == old_state) > + changed = __ibtrs_clt_change_state(sess, new_state); > + spin_unlock_irq(&sess->state_wq.lock); > + > + return changed; > +} > + > +static bool ibtrs_clt_change_state_get_old(struct ibtrs_clt_sess *sess, > + enum ibtrs_clt_state new_state, > + enum ibtrs_clt_state *old_state) > +{ > + bool changed; > + > + spin_lock_irq(&sess->state_wq.lock); > + *old_state = sess->state; > + changed = __ibtrs_clt_change_state(sess, new_state); > + spin_unlock_irq(&sess->state_wq.lock); > + > + return changed; > +} > + > +static bool ibtrs_clt_change_state(struct ibtrs_clt_sess *sess, > + enum ibtrs_clt_state new_state) > +{ > + enum ibtrs_clt_state old_state; > + > + return ibtrs_clt_change_state_get_old(sess, new_state, &old_state); > +} > + > +static enum ibtrs_clt_state ibtrs_clt_state(struct ibtrs_clt_sess *sess) > +{ > + enum ibtrs_clt_state state; > + > + spin_lock_irq(&sess->state_wq.lock); > + state = sess->state; > + spin_unlock_irq(&sess->state_wq.lock); > + > + return state; > +} > + > +static void ibtrs_clt_hb_err_handler(struct ibtrs_con *c, int err) > +{ > + struct ibtrs_clt_con *con; > + > + (void)err; > + con = container_of(c, typeof(*con), c); > + ibtrs_rdma_error_recovery(con); > +} > + > +static void ibtrs_clt_init_hb(struct ibtrs_clt_sess *sess) > +{ > + ibtrs_init_hb(&sess->s, &io_comp_cqe, > + IBTRS_HB_INTERVAL_MS, > + IBTRS_HB_MISSED_MAX, > + ibtrs_clt_hb_err_handler, > + ibtrs_wq); > +} > + > +static void ibtrs_clt_start_hb(struct ibtrs_clt_sess *sess) > +{ > + ibtrs_start_hb(&sess->s); > +} > + > +static void ibtrs_clt_stop_hb(struct ibtrs_clt_sess *sess) > +{ > + ibtrs_stop_hb(&sess->s); > +} > + > +static void ibtrs_clt_reconnect_work(struct work_struct *work); > +static void ibtrs_clt_close_work(struct work_struct *work); > + > +static struct ibtrs_clt_sess *alloc_sess(struct ibtrs_clt *clt, > + const struct ibtrs_addr *path, > + size_t con_num, u16 max_segments) > +{ > + struct ibtrs_clt_sess *sess; > + int err = -ENOMEM; > + int cpu; > + > + sess = kzalloc(sizeof(*sess), GFP_KERNEL); > + if (unlikely(!sess)) > + goto err; > + > + /* Extra connection for user messages */ > + con_num += 1; > + > + sess->s.con = kcalloc(con_num, sizeof(*sess->s.con), GFP_KERNEL); > + if (unlikely(!sess->s.con)) > + goto err_free_sess; > + > + mutex_init(&sess->init_mutex); > + uuid_gen(&sess->s.uuid); > + memcpy(&sess->s.dst_addr, path->dst, > + rdma_addr_size((struct sockaddr *)path->dst)); > + > + /* > + * rdma_resolve_addr() passes src_addr to cma_bind_addr, which > + * checks the sa_family to be non-zero. If user passed src_addr=NULL > + * the sess->src_addr will contain only zeros, which is then fine. > + */ > + if (path->src) > + memcpy(&sess->s.src_addr, path->src, > + rdma_addr_size((struct sockaddr *)path->src)); > + strlcpy(sess->s.sessname, clt->sessname, sizeof(sess->s.sessname)); > + sess->s.con_num = con_num; > + sess->clt = clt; > + sess->max_pages_per_mr = max_segments; > + init_waitqueue_head(&sess->state_wq); > + sess->state = IBTRS_CLT_CONNECTING; > + atomic_set(&sess->connected_cnt, 0); > + INIT_WORK(&sess->close_work, ibtrs_clt_close_work); > + INIT_DELAYED_WORK(&sess->reconnect_dwork, ibtrs_clt_reconnect_work); > + ibtrs_clt_init_hb(sess); > + > + sess->mp_skip_entry = alloc_percpu(typeof(*sess->mp_skip_entry)); > + if (unlikely(!sess->mp_skip_entry)) > + goto err_free_con; > + > + for_each_possible_cpu(cpu) > + INIT_LIST_HEAD(per_cpu_ptr(sess->mp_skip_entry, cpu)); > + > + err = ibtrs_clt_init_stats(&sess->stats); > + if (unlikely(err)) > + goto err_free_percpu; > + > + return sess; > + > +err_free_percpu: > + free_percpu(sess->mp_skip_entry); > +err_free_con: > + kfree(sess->s.con); > +err_free_sess: > + kfree(sess); > +err: > + return ERR_PTR(err); > +} > + > +static void free_sess(struct ibtrs_clt_sess *sess) > +{ > + ibtrs_clt_free_stats(&sess->stats); > + free_percpu(sess->mp_skip_entry); > + kfree(sess->s.con); > + kfree(sess->srv_rdma_addr); > + kfree(sess); > +} > + > +static int create_con(struct ibtrs_clt_sess *sess, unsigned int cid) > +{ > + struct ibtrs_clt_con *con; > + > + con = kzalloc(sizeof(*con), GFP_KERNEL); > + if (unlikely(!con)) > + return -ENOMEM; > + > + /* Map first two connections to the first CPU */ > + con->cpu = (cid ? cid - 1 : 0) % nr_cpu_ids; > + con->c.cid = cid; > + con->c.sess = &sess->s; > + atomic_set(&con->io_cnt, 0); > + > + sess->s.con[cid] = &con->c; > + > + return 0; > +} > + > +static void destroy_con(struct ibtrs_clt_con *con) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + > + sess->s.con[con->c.cid] = NULL; > + kfree(con); > +} > + > +static int create_con_cq_qp(struct ibtrs_clt_con *con) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + u16 cq_size, wr_queue_size; > + int err, cq_vector; > + > + /* > + * This function can fail, but still destroy_con_cq_qp() should > + * be called, this is because create_con_cq_qp() is called on cm > + * event path, thus caller/waiter never knows: have we failed before > + * create_con_cq_qp() or after. To solve this dilemma without > + * creating any additional flags just allow destroy_con_cq_qp() be > + * called many times. > + */ > + > + if (con->c.cid == 0) { > + cq_size = SERVICE_CON_QUEUE_DEPTH; > + /* + 2 for drain and heartbeat */ > + wr_queue_size = SERVICE_CON_QUEUE_DEPTH + 2; > + /* We must be the first here */ > + if (WARN_ON(sess->s.ib_dev)) > + return -EINVAL; > + > + /* > + * The whole session uses device from user connection. > + * Be careful not to close user connection before ib dev > + * is gracefully put. > + */ > + sess->s.ib_dev = ibtrs_ib_dev_find_get(con->c.cm_id); > + if (unlikely(!sess->s.ib_dev)) { > + ibtrs_wrn(sess, "ibtrs_ib_dev_find_get(): no memory\n"); > + return -ENOMEM; > + } > + sess->s.ib_dev_ref = 1; > + query_fast_reg_mode(sess); > + } else { > + int num_wr; > + > + /* > + * Here we assume that session members are correctly set. > + * This is always true if user connection (cid == 0) is > + * established first. > + */ > + if (WARN_ON(!sess->s.ib_dev)) > + return -EINVAL; > + if (WARN_ON(!sess->queue_depth)) > + return -EINVAL; > + > + /* Shared between connections */ > + sess->s.ib_dev_ref++; > + cq_size = sess->queue_depth; > + num_wr = DIV_ROUND_UP(sess->max_pages_per_mr, sess->max_sge); > + wr_queue_size = sess->s.ib_dev->attrs.max_qp_wr; > + wr_queue_size = min_t(int, wr_queue_size, > + sess->queue_depth * num_wr * > + (use_fr ? 3 : 2) + 1); > + } > + cq_vector = con->cpu % sess->s.ib_dev->dev->num_comp_vectors; > + err = ibtrs_cq_qp_create(&sess->s, &con->c, sess->max_sge, > + cq_vector, cq_size, wr_queue_size, > + IB_POLL_SOFTIRQ); > + /* > + * In case of error we do not bother to clean previous allocations, > + * since destroy_con_cq_qp() must be called. > + */ > + > + if (unlikely(err)) > + return err; > + > + if (con->c.cid) { > + err = alloc_con_fast_pool(con); > + if (unlikely(err)) > + ibtrs_cq_qp_destroy(&con->c); > + } > + > + return err; > +} > + > +static void destroy_con_cq_qp(struct ibtrs_clt_con *con) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + > + /* > + * Be careful here: destroy_con_cq_qp() can be called even > + * create_con_cq_qp() failed, see comments there. > + */ > + > + ibtrs_cq_qp_destroy(&con->c); > + if (con->c.cid != 0) > + free_con_fast_pool(con); > + if (sess->s.ib_dev_ref && !--sess->s.ib_dev_ref) { > + ibtrs_ib_dev_put(sess->s.ib_dev); > + sess->s.ib_dev = NULL; > + } > +} > + > +static void stop_cm(struct ibtrs_clt_con *con) > +{ > + rdma_disconnect(con->c.cm_id); > + if (con->c.qp) > + ib_drain_qp(con->c.qp); > +} > + > +static void destroy_cm(struct ibtrs_clt_con *con) > +{ > + rdma_destroy_id(con->c.cm_id); > + con->c.cm_id = NULL; > +} > + > +static int ibtrs_clt_rdma_cm_handler(struct rdma_cm_id *cm_id, > + struct rdma_cm_event *ev); > + > +static int create_cm(struct ibtrs_clt_con *con) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + struct rdma_cm_id *cm_id; > + int err; > + > + cm_id = rdma_create_id(&init_net, ibtrs_clt_rdma_cm_handler, con, > + sess->s.dst_addr.ss_family == AF_IB ? > + RDMA_PS_IB : RDMA_PS_TCP, IB_QPT_RC); > + if (unlikely(IS_ERR(cm_id))) { > + err = PTR_ERR(cm_id); > + ibtrs_err(sess, "Failed to create CM ID, err: %d\n", err); > + > + return err; > + } > + con->c.cm_id = cm_id; > + con->cm_err = 0; > + /* allow the port to be reused */ > + err = rdma_set_reuseaddr(cm_id, 1); > + if (err != 0) { > + ibtrs_err(sess, "Set address reuse failed, err: %d\n", err); > + goto destroy_cm; > + } > + err = rdma_resolve_addr(cm_id, (struct sockaddr *)&sess->s.src_addr, > + (struct sockaddr *)&sess->s.dst_addr, > + IBTRS_CONNECT_TIMEOUT_MS); > + if (unlikely(err)) { > + ibtrs_err(sess, "Failed to resolve address, err: %d\n", err); > + goto destroy_cm; > + } > + /* > + * Combine connection status and session events. This is needed > + * for waiting two possible cases: cm_err has something meaningful > + * or session state was really changed to error by device removal. > + */ > + err = wait_event_interruptible_timeout(sess->state_wq, > + con->cm_err || sess->state != IBTRS_CLT_CONNECTING, > + msecs_to_jiffies(IBTRS_CONNECT_TIMEOUT_MS)); > + if (unlikely(err == 0 || err == -ERESTARTSYS)) { > + if (err == 0) > + err = -ETIMEDOUT; > + /* Timedout or interrupted */ > + goto errr; > + } > + if (unlikely(con->cm_err < 0)) { > + err = con->cm_err; > + goto errr; > + } > + if (unlikely(sess->state != IBTRS_CLT_CONNECTING)) { > + /* Device removal */ > + err = -ECONNABORTED; > + goto errr; > + } > + > + return 0; > + > +errr: > + stop_cm(con); > + /* Is safe to call destroy if cq_qp is not inited */ > + destroy_con_cq_qp(con); > +destroy_cm: > + destroy_cm(con); > + > + return err; > +} > + > +static void ibtrs_clt_sess_up(struct ibtrs_clt_sess *sess) > +{ > + struct ibtrs_clt *clt = sess->clt; > + int up; > + > + /* > + * We can fire RECONNECTED event only when all paths were > + * connected on ibtrs_clt_open(), then each was disconnected > + * and the first one connected again. That's why this nasty > + * game with counter value. > + */ > + > + mutex_lock(&clt->paths_ev_mutex); > + up = ++clt->paths_up; > + /* > + * Here it is safe to access paths num directly since up counter > + * is greater than MAX_PATHS_NUM only while ibtrs_clt_open() is > + * in progress, thus paths removals are impossible. > + */ > + if (up > MAX_PATHS_NUM && up == MAX_PATHS_NUM + clt->paths_num) > + clt->paths_up = clt->paths_num; > + else if (up == 1) > + clt->link_ev(clt->priv, IBTRS_CLT_LINK_EV_RECONNECTED); > + mutex_unlock(&clt->paths_ev_mutex); > + > + /* Mark session as established */ > + sess->established = true; > + sess->reconnect_attempts = 0; > + sess->stats.reconnects.successful_cnt++; > +} > + > +static void ibtrs_clt_sess_down(struct ibtrs_clt_sess *sess) > +{ > + struct ibtrs_clt *clt = sess->clt; > + > + if (!sess->established) > + return; > + > + sess->established = false; > + mutex_lock(&clt->paths_ev_mutex); > + WARN_ON(!clt->paths_up); > + if (--clt->paths_up == 0) > + clt->link_ev(clt->priv, IBTRS_CLT_LINK_EV_DISCONNECTED); > + mutex_unlock(&clt->paths_ev_mutex); > +} > + > +static void ibtrs_clt_stop_and_destroy_conns(struct ibtrs_clt_sess *sess, > + bool failover) > +{ > + struct ibtrs_clt_con *con; > + unsigned int cid; > + > + WARN_ON(sess->state == IBTRS_CLT_CONNECTED); > + > + /* > + * Possible race with ibtrs_clt_open(), when DEVICE_REMOVAL comes > + * exactly in between. Start destroying after it finishes. > + */ > + mutex_lock(&sess->init_mutex); > + mutex_unlock(&sess->init_mutex); > + > + /* > + * All IO paths must observe !CONNECTED state before we > + * free everything. > + */ > + synchronize_rcu(); > + > + ibtrs_clt_stop_hb(sess); > + > + /* > + * The order it utterly crucial: firstly disconnect and complete all > + * rdma requests with error (thus set in_use=false for requests), > + * then fail outstanding requests checking in_use for each, and > + * eventually notify upper layer about session disconnection. > + */ > + > + for (cid = 0; cid < sess->s.con_num; cid++) { > + con = to_clt_con(sess->s.con[cid]); > + if (!con) > + break; > + > + stop_cm(con); > + } > + fail_all_outstanding_reqs(sess, failover); > + free_sess_io_bufs(sess); > + ibtrs_clt_sess_down(sess); > + > + /* > + * Wait for graceful shutdown, namely when peer side invokes > + * rdma_disconnect(). 'connected_cnt' is decremented only on > + * CM events, thus if other side had crashed and hb has detected > + * something is wrong, here we will stuck for exactly timeout ms, > + * since CM does not fire anything. That is fine, we are not in > + * hurry. > + */ > + wait_event_timeout(sess->state_wq, !atomic_read(&sess->connected_cnt), > + msecs_to_jiffies(IBTRS_CONNECT_TIMEOUT_MS)); > + > + for (cid = 0; cid < sess->s.con_num; cid++) { > + con = to_clt_con(sess->s.con[cid]); > + if (!con) > + break; > + > + destroy_con_cq_qp(con); > + destroy_cm(con); > + destroy_con(con); > + } > +} > + > +static void ibtrs_clt_remove_path_from_arr(struct ibtrs_clt_sess *sess) > +{ > + struct ibtrs_clt *clt = sess->clt; > + struct ibtrs_clt_sess *next; > + int cpu; > + > + mutex_lock(&clt->paths_mutex); > + list_del_rcu(&sess->s.entry); > + > + /* Make sure everybody observes path removal. */ > + synchronize_rcu(); > + > + /* > + * Decrement paths number only after grace period, because > + * caller of do_each_path() must firstly observe list without > + * path and only then decremented paths number. > + * > + * Otherwise there can be the following situation: > + * o Two paths exist and IO is coming. > + * o One path is removed: > + * CPU#0 CPU#1 > + * do_each_path(): ibtrs_clt_remove_path_from_arr(): > + * path = get_next_path() > + * ^^^ list_del_rcu(path) > + * [!CONNECTED path] clt->paths_num-- > + * ^^^^^^^^^ > + * load clt->paths_num from 2 to 1 > + * ^^^^^^^^^ > + * sees 1 > + * > + * path is observed as !CONNECTED, but do_each_path() loop > + * ends, because expression i < clt->paths_num is false. > + */ > + clt->paths_num--; > + > + next = list_next_or_null_rcu_rr(sess, &clt->paths_list, s.entry); > + > + /* > + * Pcpu paths can still point to the path which is going to be > + * removed, so change the pointer manually. > + */ > + for_each_possible_cpu(cpu) { > + struct ibtrs_clt_sess **ppcpu_path; > + > + ppcpu_path = per_cpu_ptr(clt->pcpu_path, cpu); > + if (*ppcpu_path != sess) > + /* > + * synchronize_rcu() was called just after deleting > + * entry from the list, thus IO code path cannot > + * change pointer back to the pointer which is going > + * to be removed, we are safe here. > + */ > + continue; > + > + /* > + * We race with IO code path, which also changes pointer, > + * thus we have to be careful not to override it. > + */ > + cmpxchg(ppcpu_path, sess, next); > + } > + mutex_unlock(&clt->paths_mutex); > +} > + > +static inline bool __ibtrs_clt_path_exists(struct ibtrs_clt *clt, > + struct ibtrs_addr *addr) > +{ > + struct ibtrs_clt_sess *sess; > + > + list_for_each_entry(sess, &clt->paths_list, s.entry) > + if (!sockaddr_cmp((struct sockaddr *)&sess->s.dst_addr, > + addr->dst)) > + return true; > + > + return false; > +} > + > +static bool ibtrs_clt_path_exists(struct ibtrs_clt *clt, > + struct ibtrs_addr *addr) > +{ > + bool res; > + > + mutex_lock(&clt->paths_mutex); > + res = __ibtrs_clt_path_exists(clt, addr); > + mutex_unlock(&clt->paths_mutex); > + > + return res; > +} > + > +static int ibtrs_clt_add_path_to_arr(struct ibtrs_clt_sess *sess, > + struct ibtrs_addr *addr) > +{ > + struct ibtrs_clt *clt = sess->clt; > + int err = 0; > + > + mutex_lock(&clt->paths_mutex); > + if (!__ibtrs_clt_path_exists(clt, addr)) { > + list_add_tail_rcu(&sess->s.entry, &clt->paths_list); > + clt->paths_num++; > + } else > + err = -EEXIST; > + mutex_unlock(&clt->paths_mutex); > + > + return err; > +} > + > +static void ibtrs_clt_close_work(struct work_struct *work) > +{ > + struct ibtrs_clt_sess *sess; > + /* > + * Always try to do a failover, if only single path remains, > + * all requests will be completed with error. > + */ > + bool failover = true; > + > + sess = container_of(work, struct ibtrs_clt_sess, close_work); > + > + cancel_delayed_work_sync(&sess->reconnect_dwork); > + ibtrs_clt_stop_and_destroy_conns(sess, failover); > + /* > + * Sounds stupid, huh? No, it is not. Consider this sequence: > + * > + * #CPU0 #CPU1 > + * 1. CONNECTED->RECONNECTING > + * 2. RECONNECTING->CLOSING > + * 3. queue_work(&reconnect_dwork) > + * 4. queue_work(&close_work); > + * 5. reconnect_work(); close_work(); > + * > + * To avoid that case do cancel twice: before and after. > + */ > + cancel_delayed_work_sync(&sess->reconnect_dwork); > + ibtrs_clt_change_state(sess, IBTRS_CLT_CLOSED); > +} > + > +static void ibtrs_clt_close_conns(struct ibtrs_clt_sess *sess, bool wait) > +{ > + if (ibtrs_clt_change_state(sess, IBTRS_CLT_CLOSING)) > + queue_work(ibtrs_wq, &sess->close_work); > + if (wait) > + flush_work(&sess->close_work); > +} > + > +static int init_conns(struct ibtrs_clt_sess *sess) > +{ > + unsigned int cid; > + int err; > + > + /* > + * On every new session connections increase reconnect counter > + * to avoid clashes with previous sessions not yet closed > + * sessions on a server side. > + */ > + sess->s.recon_cnt++; > + > + /* Establish all RDMA connections */ > + for (cid = 0; cid < sess->s.con_num; cid++) { > + err = create_con(sess, cid); > + if (unlikely(err)) > + goto destroy; > + > + err = create_cm(to_clt_con(sess->s.con[cid])); > + if (unlikely(err)) { > + destroy_con(to_clt_con(sess->s.con[cid])); > + goto destroy; > + } > + } > + /* Allocate all session related buffers */ > + err = alloc_sess_io_bufs(sess); > + if (unlikely(err)) > + goto destroy; > + > + ibtrs_clt_start_hb(sess); > + > + return 0; > + > +destroy: > + while (cid--) { > + struct ibtrs_clt_con *con = to_clt_con(sess->s.con[cid]); > + > + stop_cm(con); > + destroy_con_cq_qp(con); > + destroy_cm(con); > + destroy_con(con); > + } > + /* > + * If we've never taken async path and got an error, say, > + * doing rdma_resolve_addr(), switch to CONNECTION_ERR state > + * manually to keep reconnecting. > + */ > + ibtrs_clt_change_state(sess, IBTRS_CLT_CONNECTING_ERR); > + > + return err; > +} > + > +static int ibtrs_rdma_addr_resolved(struct ibtrs_clt_con *con) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + int err; > + > + err = create_con_cq_qp(con); > + if (unlikely(err)) { > + ibtrs_err(sess, "create_con_cq_qp(), err: %d\n", err); > + return err; > + } > + err = rdma_resolve_route(con->c.cm_id, IBTRS_CONNECT_TIMEOUT_MS); > + if (unlikely(err)) { > + ibtrs_err(sess, "Resolving route failed, err: %d\n", err); > + destroy_con_cq_qp(con); > + } > + > + return err; > +} > + > +static int ibtrs_rdma_route_resolved(struct ibtrs_clt_con *con) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + struct ibtrs_clt *clt = sess->clt; > + struct ibtrs_msg_conn_req msg; > + struct rdma_conn_param param; > + > + int err; > + > + memset(¶m, 0, sizeof(param)); > + param.retry_count = retry_count; > + param.rnr_retry_count = 7; > + param.private_data = &msg; > + param.private_data_len = sizeof(msg); > + > + /* > + * Those two are the part of struct cma_hdr which is shared > + * with private_data in case of AF_IB, so put zeroes to avoid > + * wrong validation inside cma.c on receiver side. > + */ > + msg.__cma_version = 0; > + msg.__ip_version = 0; > + msg.magic = cpu_to_le16(IBTRS_MAGIC); > + msg.version = cpu_to_le16(IBTRS_VERSION); > + msg.cid = cpu_to_le16(con->c.cid); > + msg.cid_num = cpu_to_le16(sess->s.con_num); > + msg.recon_cnt = cpu_to_le16(sess->s.recon_cnt); > + uuid_copy(&msg.sess_uuid, &sess->s.uuid); > + uuid_copy(&msg.paths_uuid, &clt->paths_uuid); > + > + err = rdma_connect(con->c.cm_id, ¶m); > + if (err) > + ibtrs_err(sess, "rdma_connect(): %d\n", err); > + > + return err; > +} > + > +static int ibtrs_rdma_conn_established(struct ibtrs_clt_con *con, > + struct rdma_cm_event *ev) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + const struct ibtrs_msg_conn_rsp *msg; > + u16 version, queue_depth; > + int errno; > + u8 len; > + > + msg = ev->param.conn.private_data; > + len = ev->param.conn.private_data_len; > + if (unlikely(len < sizeof(*msg))) { > + ibtrs_err(sess, "Invalid IBTRS connection response"); > + return -ECONNRESET; > + } > + if (unlikely(le16_to_cpu(msg->magic) != IBTRS_MAGIC)) { > + ibtrs_err(sess, "Invalid IBTRS magic"); > + return -ECONNRESET; > + } > + version = le16_to_cpu(msg->version); > + if (unlikely(version >> 8 != IBTRS_VER_MAJOR)) { > + ibtrs_err(sess, "Unsupported major IBTRS version: %d", > + version); > + return -ECONNRESET; > + } > + errno = le16_to_cpu(msg->errno); > + if (unlikely(errno)) { > + ibtrs_err(sess, "Invalid IBTRS message: errno %d", > + errno); > + return -ECONNRESET; > + } > + if (con->c.cid == 0) { > + queue_depth = le16_to_cpu(msg->queue_depth); > + > + if (queue_depth > MAX_SESS_QUEUE_DEPTH) { > + ibtrs_err(sess, "Invalid IBTRS message: queue=%d\n", > + queue_depth); > + return -ECONNRESET; > + } > + if (!sess->srv_rdma_addr || sess->queue_depth < queue_depth) { > + kfree(sess->srv_rdma_addr); > + sess->srv_rdma_addr = > + kcalloc(queue_depth, > + sizeof(*sess->srv_rdma_addr), > + GFP_KERNEL); > + if (unlikely(!sess->srv_rdma_addr)) { > + ibtrs_err(sess, "Failed to allocate " > + "queue_depth=%d\n", queue_depth); > + return -ENOMEM; > + } > + } > + sess->queue_depth = queue_depth; > + sess->srv_rdma_buf_rkey = le32_to_cpu(msg->rkey); > + sess->max_req_size = le32_to_cpu(msg->max_req_size); > + sess->max_io_size = le32_to_cpu(msg->max_io_size); > + sess->chunk_size = sess->max_io_size + sess->max_req_size; > + sess->max_desc = sess->max_req_size; > + sess->max_desc -= sizeof(u32) + sizeof(u32) + IO_MSG_SIZE; > + sess->max_desc /= sizeof(struct ibtrs_sg_desc); > + > + /* > + * Global queue depth and is always a minimum. If while a > + * reconnection server sends us a value a bit higher - > + * client does not care and uses cached minimum. > + */ > + ibtrs_clt_set_min_queue_depth(sess->clt, sess->queue_depth); > + ibtrs_clt_set_min_io_size(sess->clt, sess->max_io_size); > + } > + > + return 0; > +} > + > +static int ibtrs_rdma_conn_rejected(struct ibtrs_clt_con *con, > + struct rdma_cm_event *ev) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + const struct ibtrs_msg_conn_rsp *msg; > + const char *rej_msg; > + int status, errno; > + u8 data_len; > + > + status = ev->status; > + rej_msg = rdma_reject_msg(con->c.cm_id, status); > + msg = rdma_consumer_reject_data(con->c.cm_id, ev, &data_len); > + > + if (msg && data_len >= sizeof(*msg)) { > + errno = (int16_t)le16_to_cpu(msg->errno); > + if (errno == -EBUSY) > + ibtrs_err(sess, > + "Previous session is still exists on the " > + "server, please reconnect later\n"); > + else > + ibtrs_err(sess, > + "Connect rejected: status %d (%s), ibtrs " > + "errno %d\n", status, rej_msg, errno); > + } else { > + ibtrs_err(sess, > + "Connect rejected but with malformed message: " > + "status %d (%s)\n", status, rej_msg); > + } > + > + return -ECONNRESET; > +} > + > +static void ibtrs_rdma_error_recovery(struct ibtrs_clt_con *con) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + > + if (ibtrs_clt_change_state_from_to(sess, > + IBTRS_CLT_CONNECTED, > + IBTRS_CLT_RECONNECTING)) { > + /* > + * Normal scenario, reconnect if we were successfully connected > + */ > + queue_delayed_work(ibtrs_wq, &sess->reconnect_dwork, 0); > + } else { > + /* > + * Error can happen just on establishing new connection, > + * so notify waiter with error state, waiter is responsible > + * for cleaning the rest and reconnect if needed. > + */ > + ibtrs_clt_change_state_from_to(sess, > + IBTRS_CLT_CONNECTING, > + IBTRS_CLT_CONNECTING_ERR); > + } > +} > + > +static inline void flag_success_on_conn(struct ibtrs_clt_con *con) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + > + atomic_inc(&sess->connected_cnt); > + con->cm_err = 1; > +} > + > +static inline void flag_error_on_conn(struct ibtrs_clt_con *con, int cm_err) > +{ > + if (con->cm_err == 1) { > + struct ibtrs_clt_sess *sess; > + > + sess = to_clt_sess(con->c.sess); > + if (atomic_dec_and_test(&sess->connected_cnt)) > + wake_up(&sess->state_wq); > + } > + con->cm_err = cm_err; > +} > + > +static int ibtrs_clt_rdma_cm_handler(struct rdma_cm_id *cm_id, > + struct rdma_cm_event *ev) > +{ > + struct ibtrs_clt_con *con = cm_id->context; > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + int cm_err = 0; > + > + switch (ev->event) { > + case RDMA_CM_EVENT_ADDR_RESOLVED: > + cm_err = ibtrs_rdma_addr_resolved(con); > + break; > + case RDMA_CM_EVENT_ROUTE_RESOLVED: > + cm_err = ibtrs_rdma_route_resolved(con); > + break; > + case RDMA_CM_EVENT_ESTABLISHED: > + con->cm_err = ibtrs_rdma_conn_established(con, ev); > + if (likely(!con->cm_err)) { > + /* > + * Report success and wake up. Here we abuse state_wq, > + * i.e. wake up without state change, but we set cm_err. > + */ > + flag_success_on_conn(con); > + wake_up(&sess->state_wq); > + return 0; > + } > + break; > + case RDMA_CM_EVENT_REJECTED: > + cm_err = ibtrs_rdma_conn_rejected(con, ev); > + break; > + case RDMA_CM_EVENT_CONNECT_ERROR: > + case RDMA_CM_EVENT_UNREACHABLE: > + ibtrs_wrn(sess, "CM error event %d\n", ev->event); > + cm_err = -ECONNRESET; > + break; > + case RDMA_CM_EVENT_ADDR_ERROR: > + case RDMA_CM_EVENT_ROUTE_ERROR: > + cm_err = -EHOSTUNREACH; > + break; > + case RDMA_CM_EVENT_DISCONNECTED: > + case RDMA_CM_EVENT_ADDR_CHANGE: > + case RDMA_CM_EVENT_TIMEWAIT_EXIT: > + cm_err = -ECONNRESET; > + break; > + case RDMA_CM_EVENT_DEVICE_REMOVAL: > + /* > + * Device removal is a special case. Queue close and return 0. > + */ > + ibtrs_clt_close_conns(sess, false); > + return 0; > + default: > + ibtrs_err(sess, "Unexpected RDMA CM event (%d)\n", ev->event); > + cm_err = -ECONNRESET; > + break; > + } > + > + if (cm_err) { > + /* > + * cm error makes sense only on connection establishing, > + * in other cases we rely on normal procedure of reconnecting. > + */ > + flag_error_on_conn(con, cm_err); > + ibtrs_rdma_error_recovery(con); > + } > + > + return 0; > +} > + > +static void ibtrs_clt_info_req_done(struct ib_cq *cq, struct ib_wc *wc) > +{ > + struct ibtrs_clt_con *con = cq->cq_context; > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + struct ibtrs_iu *iu; > + > + iu = container_of(wc->wr_cqe, struct ibtrs_iu, cqe); > + ibtrs_iu_free(iu, DMA_TO_DEVICE, sess->s.ib_dev->dev); > + > + if (unlikely(wc->status != IB_WC_SUCCESS)) { > + ibtrs_err(sess, "Sess info request send failed: %s\n", > + ib_wc_status_msg(wc->status)); > + ibtrs_clt_change_state(sess, IBTRS_CLT_CONNECTING_ERR); > + return; > + } > + > + ibtrs_clt_update_wc_stats(con); > +} > + > +static int process_info_rsp(struct ibtrs_clt_sess *sess, > + const struct ibtrs_msg_info_rsp *msg) > +{ > + unsigned int addr_num; > + int i; > + > + addr_num = le16_to_cpu(msg->addr_num); > + /* > + * Check if IB immediate data size is enough to hold the mem_id and > + * the offset inside the memory chunk. > + */ > + if (unlikely(ilog2(addr_num - 1) + ilog2(sess->chunk_size - 1) > > + MAX_IMM_PAYL_BITS)) { > + ibtrs_err(sess, "RDMA immediate size (%db) not enough to " > + "encode %d buffers of size %dB\n", MAX_IMM_PAYL_BITS, > + addr_num, sess->chunk_size); > + return -EINVAL; > + } > + if (unlikely(addr_num > sess->queue_depth)) { > + ibtrs_err(sess, "Incorrect addr_num=%d\n", addr_num); > + return -EINVAL; > + } > + for (i = 0; i < msg->addr_num; i++) > + sess->srv_rdma_addr[i] = le64_to_cpu(msg->addr[i]); > + > + return 0; > +} > + > +static void ibtrs_clt_info_rsp_done(struct ib_cq *cq, struct ib_wc *wc) > +{ > + struct ibtrs_clt_con *con = cq->cq_context; > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + struct ibtrs_msg_info_rsp *msg; > + enum ibtrs_clt_state state; > + struct ibtrs_iu *iu; > + size_t rx_sz; > + int err; > + > + state = IBTRS_CLT_CONNECTING_ERR; > + > + WARN_ON(con->c.cid); > + iu = container_of(wc->wr_cqe, struct ibtrs_iu, cqe); > + if (unlikely(wc->status != IB_WC_SUCCESS)) { > + ibtrs_err(sess, "Sess info response recv failed: %s\n", > + ib_wc_status_msg(wc->status)); > + goto out; > + } > + WARN_ON(wc->opcode != IB_WC_RECV); > + > + if (unlikely(wc->byte_len < sizeof(*msg))) { > + ibtrs_err(sess, "Sess info response is malformed: size %d\n", > + wc->byte_len); > + goto out; > + } > + msg = iu->buf; > + if (unlikely(le16_to_cpu(msg->type) != IBTRS_MSG_INFO_RSP)) { > + ibtrs_err(sess, "Sess info response is malformed: type %d\n", > + le32_to_cpu(msg->type)); > + goto out; > + } > + rx_sz = sizeof(*msg); > + rx_sz += sizeof(msg->addr[0]) * le16_to_cpu(msg->addr_num); > + if (unlikely(wc->byte_len < rx_sz)) { > + ibtrs_err(sess, "Sess info response is malformed: size %d\n", > + wc->byte_len); > + goto out; > + } > + err = process_info_rsp(sess, msg); > + if (unlikely(err)) > + goto out; > + > + err = post_recv_sess(sess); > + if (unlikely(err)) > + goto out; > + > + state = IBTRS_CLT_CONNECTED; > + > +out: > + ibtrs_clt_update_wc_stats(con); > + ibtrs_iu_free(iu, DMA_FROM_DEVICE, sess->s.ib_dev->dev); > + ibtrs_clt_change_state(sess, state); > +} > + > +static int ibtrs_send_sess_info(struct ibtrs_clt_sess *sess) > +{ > + struct ibtrs_clt_con *usr_con = to_clt_con(sess->s.con[0]); > + struct ibtrs_msg_info_req *msg; > + struct ibtrs_iu *tx_iu, *rx_iu; > + size_t rx_sz; > + int err; > + > + rx_sz = sizeof(struct ibtrs_msg_info_rsp); > + rx_sz += sizeof(u64) * MAX_SESS_QUEUE_DEPTH; > + > + tx_iu = ibtrs_iu_alloc(0, sizeof(struct ibtrs_msg_info_req), GFP_KERNEL, > + sess->s.ib_dev->dev, DMA_TO_DEVICE, > + ibtrs_clt_info_req_done); > + rx_iu = ibtrs_iu_alloc(0, rx_sz, GFP_KERNEL, sess->s.ib_dev->dev, > + DMA_FROM_DEVICE, ibtrs_clt_info_rsp_done); > + if (unlikely(!tx_iu || !rx_iu)) { > + ibtrs_err(sess, "ibtrs_iu_alloc(): no memory\n"); > + err = -ENOMEM; > + goto out; > + } > + /* Prepare for getting info response */ > + err = ibtrs_iu_post_recv(&usr_con->c, rx_iu); > + if (unlikely(err)) { > + ibtrs_err(sess, "ibtrs_iu_post_recv(), err: %d\n", err); > + goto out; > + } > + rx_iu = NULL; > + > + msg = tx_iu->buf; > + msg->type = cpu_to_le16(IBTRS_MSG_INFO_REQ); > + memcpy(msg->sessname, sess->s.sessname, sizeof(msg->sessname)); > + > + /* Send info request */ > + err = ibtrs_iu_post_send(&usr_con->c, tx_iu, sizeof(*msg)); > + if (unlikely(err)) { > + ibtrs_err(sess, "ibtrs_iu_post_send(), err: %d\n", err); > + goto out; > + } > + tx_iu = NULL; > + > + /* Wait for state change */ > + wait_event_interruptible_timeout(sess->state_wq, > + sess->state != IBTRS_CLT_CONNECTING, > + msecs_to_jiffies(IBTRS_CONNECT_TIMEOUT_MS)); > + if (unlikely(sess->state != IBTRS_CLT_CONNECTED)) { > + if (sess->state == IBTRS_CLT_CONNECTING_ERR) > + err = -ECONNRESET; > + else > + err = -ETIMEDOUT; > + goto out; > + } > + > +out: > + if (tx_iu) > + ibtrs_iu_free(tx_iu, DMA_TO_DEVICE, sess->s.ib_dev->dev); > + if (rx_iu) > + ibtrs_iu_free(rx_iu, DMA_FROM_DEVICE, sess->s.ib_dev->dev); > + if (unlikely(err)) > + /* If we've never taken async path because of malloc problems */ > + ibtrs_clt_change_state(sess, IBTRS_CLT_CONNECTING_ERR); > + > + return err; > +} > + > +/** > + * init_sess() - establishes all session connections and does handshake > + * > + * In case of error full close or reconnect procedure should be taken, > + * because reconnect or close async works can be started. > + */ > +static int init_sess(struct ibtrs_clt_sess *sess) > +{ > + int err; > + > + mutex_lock(&sess->init_mutex); > + err = init_conns(sess); > + if (unlikely(err)) { > + ibtrs_err(sess, "init_conns(), err: %d\n", err); > + goto out; > + } > + err = ibtrs_send_sess_info(sess); > + if (unlikely(err)) { > + ibtrs_err(sess, "ibtrs_send_sess_info(), err: %d\n", err); > + goto out; > + } > + ibtrs_clt_sess_up(sess); > +out: > + mutex_unlock(&sess->init_mutex); > + > + return err; > +} > + > +static void ibtrs_clt_reconnect_work(struct work_struct *work) > +{ > + struct ibtrs_clt_sess *sess; > + struct ibtrs_clt *clt; > + unsigned int delay_ms; > + int err; > + > + sess = container_of(to_delayed_work(work), struct ibtrs_clt_sess, > + reconnect_dwork); > + clt = sess->clt; > + > + if (ibtrs_clt_state(sess) == IBTRS_CLT_CLOSING) > + /* User requested closing */ > + return; > + > + if (sess->reconnect_attempts >= clt->max_reconnect_attempts) { > + /* Close a session completely if max attempts is reached */ > + ibtrs_clt_close_conns(sess, false); > + return; > + } > + sess->reconnect_attempts++; > + > + /* Stop everything */ > + ibtrs_clt_stop_and_destroy_conns(sess, true); > + ibtrs_clt_change_state(sess, IBTRS_CLT_CONNECTING); > + > + err = init_sess(sess); > + if (unlikely(err)) > + goto reconnect_again; > + > + return; > + > +reconnect_again: > + if (ibtrs_clt_change_state(sess, IBTRS_CLT_RECONNECTING)) { > + sess->stats.reconnects.fail_cnt++; > + delay_ms = clt->reconnect_delay_sec * 1000; > + queue_delayed_work(ibtrs_wq, &sess->reconnect_dwork, > + msecs_to_jiffies(delay_ms)); > + } > +} > + > +static struct ibtrs_clt *alloc_clt(const char *sessname, size_t paths_num, > + short port, size_t pdu_sz, > + void *priv, link_clt_ev_fn *link_ev, > + unsigned int max_segments, > + unsigned int reconnect_delay_sec, > + unsigned int max_reconnect_attempts) > +{ > + struct ibtrs_clt *clt; > + int err; > + > + if (unlikely(!paths_num || paths_num > MAX_PATHS_NUM)) > + return ERR_PTR(-EINVAL); > + > + if (unlikely(strlen(sessname) >= sizeof(clt->sessname))) > + return ERR_PTR(-EINVAL); > + > + clt = kzalloc(sizeof(*clt), GFP_KERNEL); > + if (unlikely(!clt)) > + return ERR_PTR(-ENOMEM); > + > + clt->pcpu_path = alloc_percpu(typeof(*clt->pcpu_path)); > + if (unlikely(!clt->pcpu_path)) { > + kfree(clt); > + return ERR_PTR(-ENOMEM); > + } > + > + uuid_gen(&clt->paths_uuid); > + INIT_LIST_HEAD_RCU(&clt->paths_list); > + clt->paths_num = paths_num; > + clt->paths_up = MAX_PATHS_NUM; > + clt->port = port; > + clt->pdu_sz = pdu_sz; > + clt->max_segments = max_segments; > + clt->reconnect_delay_sec = reconnect_delay_sec; > + clt->max_reconnect_attempts = max_reconnect_attempts; > + clt->priv = priv; > + clt->link_ev = link_ev; > + clt->mp_policy = MP_POLICY_MIN_INFLIGHT; > + strlcpy(clt->sessname, sessname, sizeof(clt->sessname)); > + init_waitqueue_head(&clt->tags_wait); > + mutex_init(&clt->paths_ev_mutex); > + mutex_init(&clt->paths_mutex); > + > + err = ibtrs_clt_create_sysfs_root_folders(clt); > + if (unlikely(err)) { > + free_percpu(clt->pcpu_path); > + kfree(clt); > + return ERR_PTR(err); > + } > + > + return clt; > +} > + > +static void wait_for_inflight_tags(struct ibtrs_clt *clt) > +{ > + if (clt->tags_map) { > + size_t sz = clt->queue_depth; > + > + wait_event(clt->tags_wait, > + find_first_bit(clt->tags_map, sz) >= sz); > + } > +} > + > +static void free_clt(struct ibtrs_clt *clt) > +{ > + ibtrs_clt_destroy_sysfs_root_folders(clt); > + wait_for_inflight_tags(clt); > + free_tags(clt); > + free_percpu(clt->pcpu_path); > + kfree(clt); > +} > + > +struct ibtrs_clt *ibtrs_clt_open(void *priv, link_clt_ev_fn *link_ev, > + const char *sessname, > + const struct ibtrs_addr *paths, > + size_t paths_num, > + short port, > + size_t pdu_sz, u8 reconnect_delay_sec, > + u16 max_segments, > + s16 max_reconnect_attempts) > +{ > + struct ibtrs_clt_sess *sess, *tmp; > + struct ibtrs_clt *clt; > + int err, i; > + > + clt = alloc_clt(sessname, paths_num, port, pdu_sz, priv, link_ev, > + max_segments, reconnect_delay_sec, > + max_reconnect_attempts); > + if (unlikely(IS_ERR(clt))) { > + err = PTR_ERR(clt); > + goto out; > + } > + for (i = 0; i < paths_num; i++) { > + struct ibtrs_clt_sess *sess; > + > + sess = alloc_sess(clt, &paths[i], nr_cons_per_session, > + max_segments); > + if (unlikely(IS_ERR(sess))) { > + err = PTR_ERR(sess); > + ibtrs_err(clt, "alloc_sess(), err: %d\n", err); > + goto close_all_sess; > + } > + list_add_tail_rcu(&sess->s.entry, &clt->paths_list); > + > + err = init_sess(sess); > + if (unlikely(err)) > + goto close_all_sess; > + > + err = ibtrs_clt_create_sess_files(sess); > + if (unlikely(err)) > + goto close_all_sess; > + } > + err = alloc_tags(clt); > + if (unlikely(err)) { > + ibtrs_err(clt, "alloc_tags(), err: %d\n", err); > + goto close_all_sess; > + } > + err = ibtrs_clt_create_sysfs_root_files(clt); > + if (unlikely(err)) > + goto close_all_sess; > + > + /* > + * There is a race if someone decides to completely remove just > + * newly created path using sysfs entry. To avoid the race we > + * use simple 'opened' flag, see ibtrs_clt_remove_path_from_sysfs(). > + */ > + clt->opened = true; > + > + /* Do not let module be unloaded if client is alive */ > + __module_get(THIS_MODULE); > + > + return clt; > + > +close_all_sess: > + list_for_each_entry_safe(sess, tmp, &clt->paths_list, s.entry) { > + ibtrs_clt_destroy_sess_files(sess, NULL); > + ibtrs_clt_close_conns(sess, true); > + free_sess(sess); > + } > + free_clt(clt); > + > +out: > + return ERR_PTR(err); > +} > +EXPORT_SYMBOL(ibtrs_clt_open); > + > +void ibtrs_clt_close(struct ibtrs_clt *clt) > +{ > + struct ibtrs_clt_sess *sess, *tmp; > + > + /* Firstly forbid sysfs access */ > + ibtrs_clt_destroy_sysfs_root_files(clt); > + ibtrs_clt_destroy_sysfs_root_folders(clt); > + > + /* Now it is safe to iterate over all paths without locks */ > + list_for_each_entry_safe(sess, tmp, &clt->paths_list, s.entry) { > + ibtrs_clt_destroy_sess_files(sess, NULL); > + ibtrs_clt_close_conns(sess, true); > + free_sess(sess); > + } > + free_clt(clt); > + module_put(THIS_MODULE); > +} > +EXPORT_SYMBOL(ibtrs_clt_close); > + > +int ibtrs_clt_reconnect_from_sysfs(struct ibtrs_clt_sess *sess) > +{ > + enum ibtrs_clt_state old_state; > + int err = -EBUSY; > + bool changed; > + > + changed = ibtrs_clt_change_state_get_old(sess, IBTRS_CLT_RECONNECTING, > + &old_state); > + if (changed) { > + sess->reconnect_attempts = 0; > + queue_delayed_work(ibtrs_wq, &sess->reconnect_dwork, 0); > + } > + if (changed || old_state == IBTRS_CLT_RECONNECTING) { > + /* > + * flush_delayed_work() queues pending work for immediate > + * execution, so do the flush if we have queued something > + * right now or work is pending. > + */ > + flush_delayed_work(&sess->reconnect_dwork); > + err = ibtrs_clt_sess_is_connected(sess) ? 0 : -ENOTCONN; > + } > + > + return err; > +} > + > +int ibtrs_clt_disconnect_from_sysfs(struct ibtrs_clt_sess *sess) > +{ > + ibtrs_clt_close_conns(sess, true); > + > + return 0; > +} > + > +int ibtrs_clt_remove_path_from_sysfs(struct ibtrs_clt_sess *sess, > + const struct attribute *sysfs_self) > +{ > + struct ibtrs_clt *clt = sess->clt; > + enum ibtrs_clt_state old_state; > + bool changed; > + > + /* > + * That can happen only when userspace tries to remove path > + * very early, when ibtrs_clt_open() is not yet finished. > + */ > + if (unlikely(!clt->opened)) > + return -EBUSY; > + > + /* > + * Continue stopping path till state was changed to DEAD or > + * state was observed as DEAD: > + * 1. State was changed to DEAD - we were fast and nobody > + * invoked ibtrs_clt_reconnect(), which can again start > + * reconnecting. > + * 2. State was observed as DEAD - we have someone in parallel > + * removing the path. > + */ > + do { > + ibtrs_clt_close_conns(sess, true); > + } while (!(changed = ibtrs_clt_change_state_get_old(sess, > + IBTRS_CLT_DEAD, > + &old_state)) && > + old_state != IBTRS_CLT_DEAD); > + > + /* > + * If state was successfully changed to DEAD, commit suicide. > + */ > + if (likely(changed)) { > + ibtrs_clt_destroy_sess_files(sess, sysfs_self); > + ibtrs_clt_remove_path_from_arr(sess); > + free_sess(sess); > + } > + > + return 0; > +} > + > +void ibtrs_clt_set_max_reconnect_attempts(struct ibtrs_clt *clt, int value) > +{ > + clt->max_reconnect_attempts = (unsigned int)value; > +} > + > +int ibtrs_clt_get_max_reconnect_attempts(const struct ibtrs_clt *clt) > +{ > + return (int)clt->max_reconnect_attempts; > +} > + > +static int ibtrs_clt_rdma_write_desc(struct ibtrs_clt_con *con, > + struct ibtrs_clt_io_req *req, u64 buf, > + size_t u_msg_len, u32 imm, > + struct ibtrs_msg_rdma_write *msg) > +{ > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + struct ibtrs_sg_desc *desc; > + int ret; > + > + desc = kmalloc_array(sess->max_pages_per_mr, sizeof(*desc), GFP_ATOMIC); > + if (unlikely(!desc)) > + return -ENOMEM; > + > + ret = ibtrs_fast_reg_map_data(con, desc, req); > + if (unlikely(ret < 0)) { > + ibtrs_err_rl(sess, > + "Write request failed, fast reg. data mapping" > + " failed, err: %d\n", ret); > + kfree(desc); > + return ret; > + } > + ret = ibtrs_post_send_rdma_desc(con, req, desc, ret, buf, > + u_msg_len + sizeof(*msg), imm); > + if (unlikely(ret)) { > + ibtrs_err(sess, "Write request failed, posting work" > + " request failed, err: %d\n", ret); > + ibtrs_unmap_fast_reg_data(con, req); > + } > + kfree(desc); > + return ret; > +} > + > +static int ibtrs_clt_write_req(struct ibtrs_clt_io_req *req) > +{ > + struct ibtrs_clt_con *con = req->con; > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + struct ibtrs_msg_rdma_write *msg; > + > + int ret, count = 0; > + u32 imm, buf_id; > + u64 buf; > + > + const size_t tsize = sizeof(*msg) + req->data_len + req->usr_len; > + > + if (unlikely(tsize > sess->chunk_size)) { > + ibtrs_wrn(sess, "Write request failed, size too big %zu > %d\n", > + tsize, sess->chunk_size); > + return -EMSGSIZE; > + } > + if (req->sg_cnt) { > + count = ib_dma_map_sg(sess->s.ib_dev->dev, req->sglist, > + req->sg_cnt, req->dir); > + if (unlikely(!count)) { > + ibtrs_wrn(sess, "Write request failed, map failed\n"); > + return -EINVAL; > + } > + } > + /* put ibtrs msg after sg and user message */ > + msg = req->iu->buf + req->usr_len; > + msg->type = cpu_to_le16(IBTRS_MSG_WRITE); > + msg->usr_len = cpu_to_le16(req->usr_len); > + > + /* ibtrs message on server side will be after user data and message */ > + imm = req->tag->mem_off + req->data_len + req->usr_len; > + imm = ibtrs_to_io_req_imm(imm); > + buf_id = req->tag->mem_id; > + req->sg_size = tsize; > + buf = sess->srv_rdma_addr[buf_id]; > + > + /* > + * Update stats now, after request is successfully sent it is not > + * safe anymore to touch it. > + */ > + ibtrs_clt_update_all_stats(req, WRITE); > + > + if (count > fmr_sg_cnt) > + ret = ibtrs_clt_rdma_write_desc(req->con, req, buf, > + req->usr_len, imm, msg); > + else > + ret = ibtrs_post_send_rdma_more(req->con, req, buf, > + req->usr_len + sizeof(*msg), > + imm); > + if (unlikely(ret)) { > + ibtrs_err(sess, "Write request failed: %d\n", ret); > + ibtrs_clt_decrease_inflight(&sess->stats); > + if (req->sg_cnt) > + ib_dma_unmap_sg(sess->s.ib_dev->dev, req->sglist, > + req->sg_cnt, req->dir); > + } > + > + return ret; > +} > + > +int ibtrs_clt_write(struct ibtrs_clt *clt, ibtrs_conf_fn *conf, > + struct ibtrs_tag *tag, void *priv, const struct kvec *vec, > + size_t nr, size_t data_len, struct scatterlist *sg, > + unsigned int sg_cnt) > +{ > + struct ibtrs_clt_io_req *req; > + struct ibtrs_clt_sess *sess; > + > + int err = -ECONNABORTED; > + struct path_it it; > + size_t usr_len; > + > + usr_len = kvec_length(vec, nr); > + do_each_path(sess, clt, &it) { > + if (unlikely(sess->state != IBTRS_CLT_CONNECTED)) > + continue; > + > + if (unlikely(usr_len > IO_MSG_SIZE)) { > + ibtrs_wrn_rl(sess, "Write request failed, user message" > + " size is %zu B big, max size is %d B\n", > + usr_len, IO_MSG_SIZE); > + err = -EMSGSIZE; > + break; > + } > + req = ibtrs_clt_get_req(sess, conf, tag, priv, vec, usr_len, > + sg, sg_cnt, data_len, DMA_TO_DEVICE); > + err = ibtrs_clt_write_req(req); > + if (unlikely(err)) { > + req->in_use = false; > + continue; > + } > + /* Success path */ > + break; > + } while_each_path(&it); > + > + return err; > +} > + > +static int ibtrs_clt_read_req(struct ibtrs_clt_io_req *req) > +{ > + struct ibtrs_clt_con *con = req->con; > + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); > + struct ibtrs_msg_rdma_read *msg; > + struct ibtrs_ib_dev *ibdev; > + struct scatterlist *sg; > + > + int i, ret, count = 0; > + u32 imm, buf_id; > + > + const size_t tsize = sizeof(*msg) + req->data_len + req->usr_len; > + > + ibdev = sess->s.ib_dev; > + > + if (unlikely(tsize > sess->chunk_size)) { > + ibtrs_wrn(sess, "Read request failed, message size is" > + " %zu, bigger than CHUNK_SIZE %d\n", tsize, > + sess->chunk_size); > + return -EMSGSIZE; > + } > + > + if (req->sg_cnt) { > + count = ib_dma_map_sg(ibdev->dev, req->sglist, req->sg_cnt, > + req->dir); > + if (unlikely(!count)) { > + ibtrs_wrn(sess, "Read request failed, " > + "dma map failed\n"); > + return -EINVAL; > + } > + } > + /* put our message into req->buf after user message*/ > + msg = req->iu->buf + req->usr_len; > + msg->type = cpu_to_le16(IBTRS_MSG_READ); > + msg->sg_cnt = cpu_to_le32(count); > + msg->usr_len = cpu_to_le16(req->usr_len); > + > + if (count > fmr_sg_cnt) { > + ret = ibtrs_fast_reg_map_data(req->con, msg->desc, req); > + if (ret < 0) { > + ibtrs_err_rl(sess, > + "Read request failed, failed to map " > + " fast reg. data, err: %d\n", ret); > + ib_dma_unmap_sg(ibdev->dev, req->sglist, req->sg_cnt, > + req->dir); > + return ret; > + } > + msg->sg_cnt = cpu_to_le32(ret); > + } else { > + for_each_sg(req->sglist, sg, req->sg_cnt, i) { > + msg->desc[i].addr = > + cpu_to_le64(ib_sg_dma_address(ibdev->dev, sg)); > + msg->desc[i].key = > + cpu_to_le32(ibdev->rkey); > + msg->desc[i].len = > + cpu_to_le32(ib_sg_dma_len(ibdev->dev, sg)); > + } > + req->nmdesc = 0; > + } > + /* > + * ibtrs message will be after the space reserved for disk data and > + * user message > + */ > + imm = req->tag->mem_off + req->data_len + req->usr_len; > + imm = ibtrs_to_io_req_imm(imm); > + buf_id = req->tag->mem_id; > + > + req->sg_size = sizeof(*msg); > + req->sg_size += le32_to_cpu(msg->sg_cnt) * sizeof(struct ibtrs_sg_desc); > + req->sg_size += req->usr_len; > + > + /* > + * Update stats now, after request is successfully sent it is not > + * safe anymore to touch it. > + */ > + ibtrs_clt_update_all_stats(req, READ); > + > + ret = ibtrs_post_send_rdma(req->con, req, sess->srv_rdma_addr[buf_id], > + req->data_len, imm); > + if (unlikely(ret)) { > + ibtrs_err(sess, "Read request failed: %d\n", ret); > + ibtrs_clt_decrease_inflight(&sess->stats); > + if (unlikely(count > fmr_sg_cnt)) > + ibtrs_unmap_fast_reg_data(req->con, req); > + if (req->sg_cnt) > + ib_dma_unmap_sg(ibdev->dev, req->sglist, > + req->sg_cnt, req->dir); > + } > + > + return ret; > +} > + > +int ibtrs_clt_read(struct ibtrs_clt *clt, ibtrs_conf_fn *conf, > + struct ibtrs_tag *tag, void *priv, const struct kvec *vec, > + size_t nr, size_t data_len, struct scatterlist *sg, > + unsigned int sg_cnt) > +{ > + struct ibtrs_clt_io_req *req; > + struct ibtrs_clt_sess *sess; > + > + int err = -ECONNABORTED; > + struct path_it it; > + size_t usr_len; > + > + usr_len = kvec_length(vec, nr); > + do_each_path(sess, clt, &it) { > + if (unlikely(sess->state != IBTRS_CLT_CONNECTED)) > + continue; > + > + if (unlikely(usr_len > IO_MSG_SIZE || > + sizeof(struct ibtrs_msg_rdma_read) + > + sg_cnt * sizeof(struct ibtrs_sg_desc) > > + sess->max_req_size)) { > + ibtrs_wrn_rl(sess, "Read request failed, user message" > + " size is %zu B big, max size is %d B\n", > + usr_len, IO_MSG_SIZE); > + err = -EMSGSIZE; > + break; > + } > + req = ibtrs_clt_get_req(sess, conf, tag, priv, vec, usr_len, > + sg, sg_cnt, data_len, DMA_FROM_DEVICE); > + err = ibtrs_clt_read_req(req); > + if (unlikely(err)) { > + req->in_use = false; > + continue; > + } > + /* Success path */ > + break; > + } while_each_path(&it); > + > + return err; > +} > + > +int ibtrs_clt_request(int dir, ibtrs_conf_fn *conf, struct ibtrs_clt *clt, > + struct ibtrs_tag *tag, void *priv, const struct kvec *vec, > + size_t nr, size_t len, struct scatterlist *sg, > + unsigned int sg_len) > +{ > + if (dir == READ) > + return ibtrs_clt_read(clt, conf, tag, priv, vec, nr, len, sg, > + sg_len); > + else > + return ibtrs_clt_write(clt, conf, tag, priv, vec, nr, len, sg, > + sg_len); > +} > +EXPORT_SYMBOL(ibtrs_clt_request); > + > +int ibtrs_clt_query(struct ibtrs_clt *clt, struct ibtrs_attrs *attr) > +{ > + if (unlikely(!ibtrs_clt_is_connected(clt))) > + return -ECOMM; > + > + attr->queue_depth = clt->queue_depth; > + attr->max_io_size = clt->max_io_size; > + strlcpy(attr->sessname, clt->sessname, sizeof(attr->sessname)); > + > + return 0; > +} > +EXPORT_SYMBOL(ibtrs_clt_query); > + > +int ibtrs_clt_create_path_from_sysfs(struct ibtrs_clt *clt, > + struct ibtrs_addr *addr) > +{ > + struct ibtrs_clt_sess *sess; > + int err; > + > + if (ibtrs_clt_path_exists(clt, addr)) > + return -EEXIST; > + > + sess = alloc_sess(clt, addr, nr_cons_per_session, clt->max_segments); > + if (unlikely(IS_ERR(sess))) > + return PTR_ERR(sess); > + > + /* > + * It is totally safe to add path in CONNECTING state: coming > + * IO will never grab it. Also it is very important to add > + * path before init, since init fires LINK_CONNECTED event. > + */ > + err = ibtrs_clt_add_path_to_arr(sess, addr); > + if (unlikely(err)) > + goto free_sess; > + > + err = init_sess(sess); > + if (unlikely(err)) > + goto close_sess; > + > + err = ibtrs_clt_create_sess_files(sess); > + if (unlikely(err)) > + goto close_sess; > + > + return 0; > + > +close_sess: > + ibtrs_clt_remove_path_from_arr(sess); > + ibtrs_clt_close_conns(sess, true); > +free_sess: > + free_sess(sess); > + > + return err; > +} > + > +static int check_module_params(void) > +{ > + if (fmr_sg_cnt > MAX_SEGMENTS || fmr_sg_cnt < 0) { > + pr_err("invalid fmr_sg_cnt values\n"); > + return -EINVAL; > + } > + if (nr_cons_per_session == 0) > + nr_cons_per_session = min_t(unsigned int, nr_cpu_ids, U16_MAX); > + > + return 0; > +} > + > +static int __init ibtrs_client_init(void) > +{ > + int err; > + > + pr_info("Loading module %s, version: %s " > + "(use_fr: %d, retry_count: %d, " > + "fmr_sg_cnt: %d)\n", > + KBUILD_MODNAME, IBTRS_VER_STRING, > + use_fr, retry_count, fmr_sg_cnt); > + err = check_module_params(); > + if (err) { > + pr_err("Failed to load module, invalid module parameters," > + " err: %d\n", err); > + return err; > + } > + ibtrs_wq = alloc_workqueue("ibtrs_client_wq", WQ_MEM_RECLAIM, 0); > + if (!ibtrs_wq) { > + pr_err("Failed to load module, alloc ibtrs_client_wq failed\n"); > + return -ENOMEM; > + } > + err = ibtrs_clt_create_sysfs_module_files(); > + if (err) { > + pr_err("Failed to load module, can't create sysfs files," > + " err: %d\n", err); > + goto out_ibtrs_wq; > + } > + > + return 0; > + > +out_ibtrs_wq: > + destroy_workqueue(ibtrs_wq); > + > + return err; > +} > + > +static void __exit ibtrs_client_exit(void) > +{ > + ibtrs_clt_destroy_sysfs_module_files(); > + destroy_workqueue(ibtrs_wq); > +} > + > +module_init(ibtrs_client_init); > +module_exit(ibtrs_client_exit); >