diff options
Diffstat (limited to 'drivers/nvme/target/rdma.c')
| -rw-r--r-- | drivers/nvme/target/rdma.c | 1448 |
1 files changed, 1448 insertions, 0 deletions
diff --git a/drivers/nvme/target/rdma.c b/drivers/nvme/target/rdma.c new file mode 100644 index 000000000000..e06d504bdf0c --- /dev/null +++ b/drivers/nvme/target/rdma.c @@ -0,0 +1,1448 @@ +/* + * NVMe over Fabrics RDMA target. + * Copyright (c) 2015-2016 HGST, a Western Digital Company. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt +#include <linux/atomic.h> +#include <linux/ctype.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/nvme.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/wait.h> +#include <linux/inet.h> +#include <asm/unaligned.h> + +#include <rdma/ib_verbs.h> +#include <rdma/rdma_cm.h> +#include <rdma/rw.h> + +#include <linux/nvme-rdma.h> +#include "nvmet.h" + +/* + * We allow up to a page of inline data to go with the SQE + */ +#define NVMET_RDMA_INLINE_DATA_SIZE PAGE_SIZE + +struct nvmet_rdma_cmd { + struct ib_sge sge[2]; + struct ib_cqe cqe; + struct ib_recv_wr wr; + struct scatterlist inline_sg; + struct page *inline_page; + struct nvme_command *nvme_cmd; + struct nvmet_rdma_queue *queue; +}; + +enum { + NVMET_RDMA_REQ_INLINE_DATA = (1 << 0), + NVMET_RDMA_REQ_INVALIDATE_RKEY = (1 << 1), +}; + +struct nvmet_rdma_rsp { + struct ib_sge send_sge; + struct ib_cqe send_cqe; + struct ib_send_wr send_wr; + + struct nvmet_rdma_cmd *cmd; + struct nvmet_rdma_queue *queue; + + struct ib_cqe read_cqe; + struct rdma_rw_ctx rw; + + struct nvmet_req req; + + u8 n_rdma; + u32 flags; + u32 invalidate_rkey; + + struct list_head wait_list; + struct list_head free_list; +}; + +enum nvmet_rdma_queue_state { + NVMET_RDMA_Q_CONNECTING, + NVMET_RDMA_Q_LIVE, + NVMET_RDMA_Q_DISCONNECTING, +}; + +struct nvmet_rdma_queue { + struct rdma_cm_id *cm_id; + struct nvmet_port *port; + struct ib_cq *cq; + atomic_t sq_wr_avail; + struct nvmet_rdma_device *dev; + spinlock_t state_lock; + enum nvmet_rdma_queue_state state; + struct nvmet_cq nvme_cq; + struct nvmet_sq nvme_sq; + + struct nvmet_rdma_rsp *rsps; + struct list_head free_rsps; + spinlock_t rsps_lock; + struct nvmet_rdma_cmd *cmds; + + struct work_struct release_work; + struct list_head rsp_wait_list; + struct list_head rsp_wr_wait_list; + spinlock_t rsp_wr_wait_lock; + + int idx; + int host_qid; + int recv_queue_size; + int send_queue_size; + + struct list_head queue_list; +}; + +struct nvmet_rdma_device { + struct ib_device *device; + struct ib_pd *pd; + struct ib_srq *srq; + struct nvmet_rdma_cmd *srq_cmds; + size_t srq_size; + struct kref ref; + struct list_head entry; +}; + +static bool nvmet_rdma_use_srq; +module_param_named(use_srq, nvmet_rdma_use_srq, bool, 0444); +MODULE_PARM_DESC(use_srq, "Use shared receive queue."); + +static DEFINE_IDA(nvmet_rdma_queue_ida); +static LIST_HEAD(nvmet_rdma_queue_list); +static DEFINE_MUTEX(nvmet_rdma_queue_mutex); + +static LIST_HEAD(device_list); +static DEFINE_MUTEX(device_list_mutex); + +static bool nvmet_rdma_execute_command(struct nvmet_rdma_rsp *rsp); +static void nvmet_rdma_send_done(struct ib_cq *cq, struct ib_wc *wc); +static void nvmet_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc); +static void nvmet_rdma_read_data_done(struct ib_cq *cq, struct ib_wc *wc); +static void nvmet_rdma_qp_event(struct ib_event *event, void *priv); +static void nvmet_rdma_queue_disconnect(struct nvmet_rdma_queue *queue); + +static struct nvmet_fabrics_ops nvmet_rdma_ops; + +/* XXX: really should move to a generic header sooner or later.. */ +static inline u32 get_unaligned_le24(const u8 *p) +{ + return (u32)p[0] | (u32)p[1] << 8 | (u32)p[2] << 16; +} + +static inline bool nvmet_rdma_need_data_in(struct nvmet_rdma_rsp *rsp) +{ + return nvme_is_write(rsp->req.cmd) && + rsp->req.data_len && + !(rsp->flags & NVMET_RDMA_REQ_INLINE_DATA); +} + +static inline bool nvmet_rdma_need_data_out(struct nvmet_rdma_rsp *rsp) +{ + return !nvme_is_write(rsp->req.cmd) && + rsp->req.data_len && + !rsp->req.rsp->status && + !(rsp->flags & NVMET_RDMA_REQ_INLINE_DATA); +} + +static inline struct nvmet_rdma_rsp * +nvmet_rdma_get_rsp(struct nvmet_rdma_queue *queue) +{ + struct nvmet_rdma_rsp *rsp; + unsigned long flags; + + spin_lock_irqsave(&queue->rsps_lock, flags); + rsp = list_first_entry(&queue->free_rsps, + struct nvmet_rdma_rsp, free_list); + list_del(&rsp->free_list); + spin_unlock_irqrestore(&queue->rsps_lock, flags); + + return rsp; +} + +static inline void +nvmet_rdma_put_rsp(struct nvmet_rdma_rsp *rsp) +{ + unsigned long flags; + + spin_lock_irqsave(&rsp->queue->rsps_lock, flags); + list_add_tail(&rsp->free_list, &rsp->queue->free_rsps); + spin_unlock_irqrestore(&rsp->queue->rsps_lock, flags); +} + +static void nvmet_rdma_free_sgl(struct scatterlist *sgl, unsigned int nents) +{ + struct scatterlist *sg; + int count; + + if (!sgl || !nents) + return; + + for_each_sg(sgl, sg, nents, count) + __free_page(sg_page(sg)); + kfree(sgl); +} + +static int nvmet_rdma_alloc_sgl(struct scatterlist **sgl, unsigned int *nents, + u32 length) +{ + struct scatterlist *sg; + struct page *page; + unsigned int nent; + int i = 0; + + nent = DIV_ROUND_UP(length, PAGE_SIZE); + sg = kmalloc_array(nent, sizeof(struct scatterlist), GFP_KERNEL); + if (!sg) + goto out; + + sg_init_table(sg, nent); + + while (length) { + u32 page_len = min_t(u32, length, PAGE_SIZE); + + page = alloc_page(GFP_KERNEL); + if (!page) + goto out_free_pages; + + sg_set_page(&sg[i], page, page_len, 0); + length -= page_len; + i++; + } + *sgl = sg; + *nents = nent; + return 0; + +out_free_pages: + while (i > 0) { + i--; + __free_page(sg_page(&sg[i])); + } + kfree(sg); +out: + return NVME_SC_INTERNAL; +} + +static int nvmet_rdma_alloc_cmd(struct nvmet_rdma_device *ndev, + struct nvmet_rdma_cmd *c, bool admin) +{ + /* NVMe command / RDMA RECV */ + c->nvme_cmd = kmalloc(sizeof(*c->nvme_cmd), GFP_KERNEL); + if (!c->nvme_cmd) + goto out; + + c->sge[0].addr = ib_dma_map_single(ndev->device, c->nvme_cmd, + sizeof(*c->nvme_cmd), DMA_FROM_DEVICE); + if (ib_dma_mapping_error(ndev->device, c->sge[0].addr)) + goto out_free_cmd; + + c->sge[0].length = sizeof(*c->nvme_cmd); + c->sge[0].lkey = ndev->pd->local_dma_lkey; + + if (!admin) { + c->inline_page = alloc_pages(GFP_KERNEL, + get_order(NVMET_RDMA_INLINE_DATA_SIZE)); + if (!c->inline_page) + goto out_unmap_cmd; + c->sge[1].addr = ib_dma_map_page(ndev->device, + c->inline_page, 0, NVMET_RDMA_INLINE_DATA_SIZE, + DMA_FROM_DEVICE); + if (ib_dma_mapping_error(ndev->device, c->sge[1].addr)) + goto out_free_inline_page; + c->sge[1].length = NVMET_RDMA_INLINE_DATA_SIZE; + c->sge[1].lkey = ndev->pd->local_dma_lkey; + } + + c->cqe.done = nvmet_rdma_recv_done; + + c->wr.wr_cqe = &c->cqe; + c->wr.sg_list = c->sge; + c->wr.num_sge = admin ? 1 : 2; + + return 0; + +out_free_inline_page: + if (!admin) { + __free_pages(c->inline_page, + get_order(NVMET_RDMA_INLINE_DATA_SIZE)); + } +out_unmap_cmd: + ib_dma_unmap_single(ndev->device, c->sge[0].addr, + sizeof(*c->nvme_cmd), DMA_FROM_DEVICE); +out_free_cmd: + kfree(c->nvme_cmd); + +out: + return -ENOMEM; +} + +static void nvmet_rdma_free_cmd(struct nvmet_rdma_device *ndev, + struct nvmet_rdma_cmd *c, bool admin) +{ + if (!admin) { + ib_dma_unmap_page(ndev->device, c->sge[1].addr, + NVMET_RDMA_INLINE_DATA_SIZE, DMA_FROM_DEVICE); + __free_pages(c->inline_page, + get_order(NVMET_RDMA_INLINE_DATA_SIZE)); + } + ib_dma_unmap_single(ndev->device, c->sge[0].addr, + sizeof(*c->nvme_cmd), DMA_FROM_DEVICE); + kfree(c->nvme_cmd); +} + +static struct nvmet_rdma_cmd * +nvmet_rdma_alloc_cmds(struct nvmet_rdma_device *ndev, + int nr_cmds, bool admin) +{ + struct nvmet_rdma_cmd *cmds; + int ret = -EINVAL, i; + + cmds = kcalloc(nr_cmds, sizeof(struct nvmet_rdma_cmd), GFP_KERNEL); + if (!cmds) + goto out; + + for (i = 0; i < nr_cmds; i++) { + ret = nvmet_rdma_alloc_cmd(ndev, cmds + i, admin); + if (ret) + goto out_free; + } + + return cmds; + +out_free: + while (--i >= 0) + nvmet_rdma_free_cmd(ndev, cmds + i, admin); + kfree(cmds); +out: + return ERR_PTR(ret); +} + +static void nvmet_rdma_free_cmds(struct nvmet_rdma_device *ndev, + struct nvmet_rdma_cmd *cmds, int nr_cmds, bool admin) +{ + int i; + + for (i = 0; i < nr_cmds; i++) + nvmet_rdma_free_cmd(ndev, cmds + i, admin); + kfree(cmds); +} + +static int nvmet_rdma_alloc_rsp(struct nvmet_rdma_device *ndev, + struct nvmet_rdma_rsp *r) +{ + /* NVMe CQE / RDMA SEND */ + r->req.rsp = kmalloc(sizeof(*r->req.rsp), GFP_KERNEL); + if (!r->req.rsp) + goto out; + + r->send_sge.addr = ib_dma_map_single(ndev->device, r->req.rsp, + sizeof(*r->req.rsp), DMA_TO_DEVICE); + if (ib_dma_mapping_error(ndev->device, r->send_sge.addr)) + goto out_free_rsp; + + r->send_sge.length = sizeof(*r->req.rsp); + r->send_sge.lkey = ndev->pd->local_dma_lkey; + + r->send_cqe.done = nvmet_rdma_send_done; + + r->send_wr.wr_cqe = &r->send_cqe; + r->send_wr.sg_list = &r->send_sge; + r->send_wr.num_sge = 1; + r->send_wr.send_flags = IB_SEND_SIGNALED; + + /* Data In / RDMA READ */ + r->read_cqe.done = nvmet_rdma_read_data_done; + return 0; + +out_free_rsp: + kfree(r->req.rsp); +out: + return -ENOMEM; +} + +static void nvmet_rdma_free_rsp(struct nvmet_rdma_device *ndev, + struct nvmet_rdma_rsp *r) +{ + ib_dma_unmap_single(ndev->device, r->send_sge.addr, + sizeof(*r->req.rsp), DMA_TO_DEVICE); + kfree(r->req.rsp); +} + +static int +nvmet_rdma_alloc_rsps(struct nvmet_rdma_queue *queue) +{ + struct nvmet_rdma_device *ndev = queue->dev; + int nr_rsps = queue->recv_queue_size * 2; + int ret = -EINVAL, i; + + queue->rsps = kcalloc(nr_rsps, sizeof(struct nvmet_rdma_rsp), + GFP_KERNEL); + if (!queue->rsps) + goto out; + + for (i = 0; i < nr_rsps; i++) { + struct nvmet_rdma_rsp *rsp = &queue->rsps[i]; + + ret = nvmet_rdma_alloc_rsp(ndev, rsp); + if (ret) + goto out_free; + + list_add_tail(&rsp->free_list, &queue->free_rsps); + } + + return 0; + +out_free: + while (--i >= 0) { + struct nvmet_rdma_rsp *rsp = &queue->rsps[i]; + + list_del(&rsp->free_list); + nvmet_rdma_free_rsp(ndev, rsp); + } + kfree(queue->rsps); +out: + return ret; +} + +static void nvmet_rdma_free_rsps(struct nvmet_rdma_queue *queue) +{ + struct nvmet_rdma_device *ndev = queue->dev; + int i, nr_rsps = queue->recv_queue_size * 2; + + for (i = 0; i < nr_rsps; i++) { + struct nvmet_rdma_rsp *rsp = &queue->rsps[i]; + + list_del(&rsp->free_list); + nvmet_rdma_free_rsp(ndev, rsp); + } + kfree(queue->rsps); +} + +static int nvmet_rdma_post_recv(struct nvmet_rdma_device *ndev, + struct nvmet_rdma_cmd *cmd) +{ + struct ib_recv_wr *bad_wr; + + if (ndev->srq) + return ib_post_srq_recv(ndev->srq, &cmd->wr, &bad_wr); + return ib_post_recv(cmd->queue->cm_id->qp, &cmd->wr, &bad_wr); +} + +static void nvmet_rdma_process_wr_wait_list(struct nvmet_rdma_queue *queue) +{ + spin_lock(&queue->rsp_wr_wait_lock); + while (!list_empty(&queue->rsp_wr_wait_list)) { + struct nvmet_rdma_rsp *rsp; + bool ret; + + rsp = list_entry(queue->rsp_wr_wait_list.next, + struct nvmet_rdma_rsp, wait_list); + list_del(&rsp->wait_list); + + spin_unlock(&queue->rsp_wr_wait_lock); + ret = nvmet_rdma_execute_command(rsp); + spin_lock(&queue->rsp_wr_wait_lock); + + if (!ret) { + list_add(&rsp->wait_list, &queue->rsp_wr_wait_list); + break; + } + } + spin_unlock(&queue->rsp_wr_wait_lock); +} + + +static void nvmet_rdma_release_rsp(struct nvmet_rdma_rsp *rsp) +{ + struct nvmet_rdma_queue *queue = rsp->queue; + + atomic_add(1 + rsp->n_rdma, &queue->sq_wr_avail); + + if (rsp->n_rdma) { + rdma_rw_ctx_destroy(&rsp->rw, queue->cm_id->qp, + queue->cm_id->port_num, rsp->req.sg, + rsp->req.sg_cnt, nvmet_data_dir(&rsp->req)); + } + + if (rsp->req.sg != &rsp->cmd->inline_sg) + nvmet_rdma_free_sgl(rsp->req.sg, rsp->req.sg_cnt); + + if (unlikely(!list_empty_careful(&queue->rsp_wr_wait_list))) + nvmet_rdma_process_wr_wait_list(queue); + + nvmet_rdma_put_rsp(rsp); +} + +static void nvmet_rdma_error_comp(struct nvmet_rdma_queue *queue) +{ + if (queue->nvme_sq.ctrl) { + nvmet_ctrl_fatal_error(queue->nvme_sq.ctrl); + } else { + /* + * we didn't setup the controller yet in case + * of admin connect error, just disconnect and + * cleanup the queue + */ + nvmet_rdma_queue_disconnect(queue); + } +} + +static void nvmet_rdma_send_done(struct ib_cq *cq, struct ib_wc *wc) +{ + struct nvmet_rdma_rsp *rsp = + container_of(wc->wr_cqe, struct nvmet_rdma_rsp, send_cqe); + + nvmet_rdma_release_rsp(rsp); + + if (unlikely(wc->status != IB_WC_SUCCESS && + wc->status != IB_WC_WR_FLUSH_ERR)) { + pr_err("SEND for CQE 0x%p failed with status %s (%d).\n", + wc->wr_cqe, ib_wc_status_msg(wc->status), wc->status); + nvmet_rdma_error_comp(rsp->queue); + } +} + +static void nvmet_rdma_queue_response(struct nvmet_req *req) +{ + struct nvmet_rdma_rsp *rsp = + container_of(req, struct nvmet_rdma_rsp, req); + struct rdma_cm_id *cm_id = rsp->queue->cm_id; + struct ib_send_wr *first_wr, *bad_wr; + + if (rsp->flags & NVMET_RDMA_REQ_INVALIDATE_RKEY) { + rsp->send_wr.opcode = IB_WR_SEND_WITH_INV; + rsp->send_wr.ex.invalidate_rkey = rsp->invalidate_rkey; + } else { + rsp->send_wr.opcode = IB_WR_SEND; + } + + if (nvmet_rdma_need_data_out(rsp)) + first_wr = rdma_rw_ctx_wrs(&rsp->rw, cm_id->qp, + cm_id->port_num, NULL, &rsp->send_wr); + else + first_wr = &rsp->send_wr; + + nvmet_rdma_post_recv(rsp->queue->dev, rsp->cmd); + if (ib_post_send(cm_id->qp, first_wr, &bad_wr)) { + pr_err("sending cmd response failed\n"); + nvmet_rdma_release_rsp(rsp); + } +} + +static void nvmet_rdma_read_data_done(struct ib_cq *cq, struct ib_wc *wc) +{ + struct nvmet_rdma_rsp *rsp = + container_of(wc->wr_cqe, struct nvmet_rdma_rsp, read_cqe); + struct nvmet_rdma_queue *queue = cq->cq_context; + + WARN_ON(rsp->n_rdma <= 0); + atomic_add(rsp->n_rdma, &queue->sq_wr_avail); + rdma_rw_ctx_destroy(&rsp->rw, queue->cm_id->qp, + queue->cm_id->port_num, rsp->req.sg, + rsp->req.sg_cnt, nvmet_data_dir(&rsp->req)); + rsp->n_rdma = 0; + + if (unlikely(wc->status != IB_WC_SUCCESS)) { + nvmet_rdma_release_rsp(rsp); + if (wc->status != IB_WC_WR_FLUSH_ERR) { + pr_info("RDMA READ for CQE 0x%p failed with status %s (%d).\n", + wc->wr_cqe, ib_wc_status_msg(wc->status), wc->status); + nvmet_rdma_error_comp(queue); + } + return; + } + + rsp->req.execute(&rsp->req); +} + +static void nvmet_rdma_use_inline_sg(struct nvmet_rdma_rsp *rsp, u32 len, + u64 off) +{ + sg_init_table(&rsp->cmd->inline_sg, 1); + sg_set_page(&rsp->cmd->inline_sg, rsp->cmd->inline_page, len, off); + rsp->req.sg = &rsp->cmd->inline_sg; + rsp->req.sg_cnt = 1; +} + +static u16 nvmet_rdma_map_sgl_inline(struct nvmet_rdma_rsp *rsp) +{ + struct nvme_sgl_desc *sgl = &rsp->req.cmd->common.dptr.sgl; + u64 off = le64_to_cpu(sgl->addr); + u32 len = le32_to_cpu(sgl->length); + + if (!nvme_is_write(rsp->req.cmd)) + return NVME_SC_INVALID_FIELD | NVME_SC_DNR; + + if (off + len > NVMET_RDMA_INLINE_DATA_SIZE) { + pr_err("invalid inline data offset!\n"); + return NVME_SC_SGL_INVALID_OFFSET | NVME_SC_DNR; + } + + /* no data command? */ + if (!len) + return 0; + + nvmet_rdma_use_inline_sg(rsp, len, off); + rsp->flags |= NVMET_RDMA_REQ_INLINE_DATA; + return 0; +} + +static u16 nvmet_rdma_map_sgl_keyed(struct nvmet_rdma_rsp *rsp, + struct nvme_keyed_sgl_desc *sgl, bool invalidate) +{ + struct rdma_cm_id *cm_id = rsp->queue->cm_id; + u64 addr = le64_to_cpu(sgl->addr); + u32 len = get_unaligned_le24(sgl->length); + u32 key = get_unaligned_le32(sgl->key); + int ret; + u16 status; + + /* no data command? */ + if (!len) + return 0; + + /* use the already allocated data buffer if possible */ + if (len <= NVMET_RDMA_INLINE_DATA_SIZE && rsp->queue->host_qid) { + nvmet_rdma_use_inline_sg(rsp, len, 0); + } else { + status = nvmet_rdma_alloc_sgl(&rsp->req.sg, &rsp->req.sg_cnt, + len); + if (status) + return status; + } + + ret = rdma_rw_ctx_init(&rsp->rw, cm_id->qp, cm_id->port_num, + rsp->req.sg, rsp->req.sg_cnt, 0, addr, key, + nvmet_data_dir(&rsp->req)); + if (ret < 0) + return NVME_SC_INTERNAL; + rsp->n_rdma += ret; + + if (invalidate) { + rsp->invalidate_rkey = key; + rsp->flags |= NVMET_RDMA_REQ_INVALIDATE_RKEY; + } + + return 0; +} + +static u16 nvmet_rdma_map_sgl(struct nvmet_rdma_rsp *rsp) +{ + struct nvme_keyed_sgl_desc *sgl = &rsp->req.cmd->common.dptr.ksgl; + + switch (sgl->type >> 4) { + case NVME_SGL_FMT_DATA_DESC: + switch (sgl->type & 0xf) { + case NVME_SGL_FMT_OFFSET: + return nvmet_rdma_map_sgl_inline(rsp); + default: + pr_err("invalid SGL subtype: %#x\n", sgl->type); + return NVME_SC_INVALID_FIELD | NVME_SC_DNR; + } + case NVME_KEY_SGL_FMT_DATA_DESC: + switch (sgl->type & 0xf) { + case NVME_SGL_FMT_ADDRESS | NVME_SGL_FMT_INVALIDATE: + return nvmet_rdma_map_sgl_keyed(rsp, sgl, true); + case NVME_SGL_FMT_ADDRESS: + return nvmet_rdma_map_sgl_keyed(rsp, sgl, false); + default: + pr_err("invalid SGL subtype: %#x\n", sgl->type); + return NVME_SC_INVALID_FIELD | NVME_SC_DNR; + } + default: + pr_err("invalid SGL type: %#x\n", sgl->type); + return NVME_SC_SGL_INVALID_TYPE | NVME_SC_DNR; + } +} + +static bool nvmet_rdma_execute_command(struct nvmet_rdma_rsp *rsp) +{ + struct nvmet_rdma_queue *queue = rsp->queue; + + if (unlikely(atomic_sub_return(1 + rsp->n_rdma, + &queue->sq_wr_avail) < 0)) { + pr_debug("IB send queue full (needed %d): queue %u cntlid %u\n", + 1 + rsp->n_rdma, queue->idx, + queue->nvme_sq.ctrl->cntlid); + atomic_add(1 + rsp->n_rdma, &queue->sq_wr_avail); + return false; + } + + if (nvmet_rdma_need_data_in(rsp)) { + if (rdma_rw_ctx_post(&rsp->rw, queue->cm_id->qp, + queue->cm_id->port_num, &rsp->read_cqe, NULL)) + nvmet_req_complete(&rsp->req, NVME_SC_DATA_XFER_ERROR); + } else { + rsp->req.execute(&rsp->req); + } + + return true; +} + +static void nvmet_rdma_handle_command(struct nvmet_rdma_queue *queue, + struct nvmet_rdma_rsp *cmd) +{ + u16 status; + + cmd->queue = queue; + cmd->n_rdma = 0; + cmd->req.port = queue->port; + + if (!nvmet_req_init(&cmd->req, &queue->nvme_cq, + &queue->nvme_sq, &nvmet_rdma_ops)) + return; + + status = nvmet_rdma_map_sgl(cmd); + if (status) + goto out_err; + + if (unlikely(!nvmet_rdma_execute_command(cmd))) { + spin_lock(&queue->rsp_wr_wait_lock); + list_add_tail(&cmd->wait_list, &queue->rsp_wr_wait_list); + spin_unlock(&queue->rsp_wr_wait_lock); + } + + return; + +out_err: + nvmet_req_complete(&cmd->req, status); +} + +static void nvmet_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc) +{ + struct nvmet_rdma_cmd *cmd = + container_of(wc->wr_cqe, struct nvmet_rdma_cmd, cqe); + struct nvmet_rdma_queue *queue = cq->cq_context; + struct nvmet_rdma_rsp *rsp; + + if (unlikely(wc->status != IB_WC_SUCCESS)) { + if (wc->status != IB_WC_WR_FLUSH_ERR) { + pr_err("RECV for CQE 0x%p failed with status %s (%d)\n", + wc->wr_cqe, ib_wc_status_msg(wc->status), + wc->status); + nvmet_rdma_error_comp(queue); + } + return; + } + + if (unlikely(wc->byte_len < sizeof(struct nvme_command))) { + pr_err("Ctrl Fatal Error: capsule size less than 64 bytes\n"); + nvmet_rdma_error_comp(queue); + return; + } + + cmd->queue = queue; + rsp = nvmet_rdma_get_rsp(queue); + rsp->cmd = cmd; + rsp->flags = 0; + rsp->req.cmd = cmd->nvme_cmd; + + if (unlikely(queue->state != NVMET_RDMA_Q_LIVE)) { + unsigned long flags; + + spin_lock_irqsave(&queue->state_lock, flags); + if (queue->state == NVMET_RDMA_Q_CONNECTING) + list_add_tail(&rsp->wait_list, &queue->rsp_wait_list); + else + nvmet_rdma_put_rsp(rsp); + spin_unlock_irqrestore(&queue->state_lock, flags); + return; + } + + nvmet_rdma_handle_command(queue, rsp); +} + +static void nvmet_rdma_destroy_srq(struct nvmet_rdma_device *ndev) +{ + if (!ndev->srq) + return; + + nvmet_rdma_free_cmds(ndev, ndev->srq_cmds, ndev->srq_size, false); + ib_destroy_srq(ndev->srq); +} + +static int nvmet_rdma_init_srq(struct nvmet_rdma_device *ndev) +{ + struct ib_srq_init_attr srq_attr = { NULL, }; + struct ib_srq *srq; + size_t srq_size; + int ret, i; + + srq_size = 4095; /* XXX: tune */ + + srq_attr.attr.max_wr = srq_size; + srq_attr.attr.max_sge = 2; + srq_attr.attr.srq_limit = 0; + srq_attr.srq_type = IB_SRQT_BASIC; + srq = ib_create_srq(ndev->pd, &srq_attr); + if (IS_ERR(srq)) { + /* + * If SRQs aren't supported we just go ahead and use normal + * non-shared receive queues. + */ + pr_info("SRQ requested but not supported.\n"); + return 0; + } + + ndev->srq_cmds = nvmet_rdma_alloc_cmds(ndev, srq_size, false); + if (IS_ERR(ndev->srq_cmds)) { + ret = PTR_ERR(ndev->srq_cmds); + goto out_destroy_srq; + } + + ndev->srq = srq; + ndev->srq_size = srq_size; + + for (i = 0; i < srq_size; i++) + nvmet_rdma_post_recv(ndev, &ndev->srq_cmds[i]); + + return 0; + +out_destroy_srq: + ib_destroy_srq(srq); + return ret; +} + +static void nvmet_rdma_free_dev(struct kref *ref) +{ + struct nvmet_rdma_device *ndev = + container_of(ref, struct nvmet_rdma_device, ref); + + mutex_lock(&device_list_mutex); + list_del(&ndev->entry); + mutex_unlock(&device_list_mutex); + + nvmet_rdma_destroy_srq(ndev); + ib_dealloc_pd(ndev->pd); + + kfree(ndev); +} + +static struct nvmet_rdma_device * +nvmet_rdma_find_get_device(struct rdma_cm_id *cm_id) +{ + struct nvmet_rdma_device *ndev; + int ret; + + mutex_lock(&device_list_mutex); + list_for_each_entry(ndev, &device_list, entry) { + if (ndev->device->node_guid == cm_id->device->node_guid && + kref_get_unless_zero(&ndev->ref)) + goto out_unlock; + } + + ndev = kzalloc(sizeof(*ndev), GFP_KERNEL); + if (!ndev) + goto out_err; + + ndev->device = cm_id->device; + kref_init(&ndev->ref); + + ndev->pd = ib_alloc_pd(ndev->device); + if (IS_ERR(ndev->pd)) + goto out_free_dev; + + if (nvmet_rdma_use_srq) { + ret = nvmet_rdma_init_srq(ndev); + if (ret) + goto out_free_pd; + } + + list_add(&ndev->entry, &device_list); +out_unlock: + mutex_unlock(&device_list_mutex); + pr_debug("added %s.\n", ndev->device->name); + return ndev; + +out_free_pd: + ib_dealloc_pd(ndev->pd); +out_free_dev: + kfree(ndev); +out_err: + mutex_unlock(&device_list_mutex); + return NULL; +} + +static int nvmet_rdma_create_queue_ib(struct nvmet_rdma_queue *queue) +{ + struct ib_qp_init_attr qp_attr; + struct nvmet_rdma_device *ndev = queue->dev; + int comp_vector, nr_cqe, ret, i; + + /* + * Spread the io queues across completion vectors, + * but still keep all admin queues on vector 0. + */ + comp_vector = !queue->host_qid ? 0 : + queue->idx % ndev->device->num_comp_vectors; + + /* + * Reserve CQ slots for RECV + RDMA_READ/RDMA_WRITE + RDMA_SEND. + */ + nr_cqe = queue->recv_queue_size + 2 * queue->send_queue_size; + + queue->cq = ib_alloc_cq(ndev->device, queue, + nr_cqe + 1, comp_vector, + IB_POLL_WORKQUEUE); + if (IS_ERR(queue->cq)) { + ret = PTR_ERR(queue->cq); + pr_err("failed to create CQ cqe= %d ret= %d\n", + nr_cqe + 1, ret); + goto out; + } + + memset(&qp_attr, 0, sizeof(qp_attr)); + qp_attr.qp_context = queue; + qp_attr.event_handler = nvmet_rdma_qp_event; + qp_attr.send_cq = queue->cq; + qp_attr.recv_cq = queue->cq; + qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR; + qp_attr.qp_type = IB_QPT_RC; + /* +1 for drain */ + qp_attr.cap.max_send_wr = queue->send_queue_size + 1; + qp_attr.cap.max_rdma_ctxs = queue->send_queue_size; + qp_attr.cap.max_send_sge = max(ndev->device->attrs.max_sge_rd, + ndev->device->attrs.max_sge); + + if (ndev->srq) { + qp_attr.srq = ndev->srq; + } else { + /* +1 for drain */ + qp_attr.cap.max_recv_wr = 1 + queue->recv_queue_size; + qp_attr.cap.max_recv_sge = 2; + } + + ret = rdma_create_qp(queue->cm_id, ndev->pd, &qp_attr); + if (ret) { + pr_err("failed to create_qp ret= %d\n", ret); + goto err_destroy_cq; + } + + atomic_set(&queue->sq_wr_avail, qp_attr.cap.max_send_wr); + + pr_debug("%s: max_cqe= %d max_sge= %d sq_size = %d cm_id= %p\n", + __func__, queue->cq->cqe, qp_attr.cap.max_send_sge, + qp_attr.cap.max_send_wr, queue->cm_id); + + if (!ndev->srq) { + for (i = 0; i < queue->recv_queue_size; i++) { + queue->cmds[i].queue = queue; + nvmet_rdma_post_recv(ndev, &queue->cmds[i]); + } + } + +out: + return ret; + +err_destroy_cq: + ib_free_cq(queue->cq); + goto out; +} + +static void nvmet_rdma_destroy_queue_ib(struct nvmet_rdma_queue *queue) +{ + rdma_destroy_qp(queue->cm_id); + ib_free_cq(queue->cq); +} + +static void nvmet_rdma_free_queue(struct nvmet_rdma_queue *queue) +{ + pr_info("freeing queue %d\n", queue->idx); + + nvmet_sq_destroy(&queue->nvme_sq); + + nvmet_rdma_destroy_queue_ib(queue); + if (!queue->dev->srq) { + nvmet_rdma_free_cmds(queue->dev, queue->cmds, + queue->recv_queue_size, + !queue->host_qid); + } + nvmet_rdma_free_rsps(queue); + ida_simple_remove(&nvmet_rdma_queue_ida, queue->idx); + kfree(queue); +} + +static void nvmet_rdma_release_queue_work(struct work_struct *w) +{ + struct nvmet_rdma_queue *queue = + container_of(w, struct nvmet_rdma_queue, release_work); + struct rdma_cm_id *cm_id = queue->cm_id; + struct nvmet_rdma_device *dev = queue->dev; + + nvmet_rdma_free_queue(queue); + rdma_destroy_id(cm_id); + kref_put(&dev->ref, nvmet_rdma_free_dev); +} + +static int +nvmet_rdma_parse_cm_connect_req(struct rdma_conn_param *conn, + struct nvmet_rdma_queue *queue) +{ + struct nvme_rdma_cm_req *req; + + req = (struct nvme_rdma_cm_req *)conn->private_data; + if (!req || conn->private_data_len == 0) + return NVME_RDMA_CM_INVALID_LEN; + + if (le16_to_cpu(req->recfmt) != NVME_RDMA_CM_FMT_1_0) + return NVME_RDMA_CM_INVALID_RECFMT; + + queue->host_qid = le16_to_cpu(req->qid); + + /* + * req->hsqsize corresponds to our recv queue size + * req->hrqsize corresponds to our send queue size + */ + queue->recv_queue_size = le16_to_cpu(req->hsqsize); + queue->send_queue_size = le16_to_cpu(req->hrqsize); + + if (!queue->host_qid && queue->recv_queue_size > NVMF_AQ_DEPTH) + return NVME_RDMA_CM_INVALID_HSQSIZE; + + /* XXX: Should we enforce some kind of max for IO queues? */ + + return 0; +} + +static int nvmet_rdma_cm_reject(struct rdma_cm_id *cm_id, + enum nvme_rdma_cm_status status) +{ + struct nvme_rdma_cm_rej rej; + + rej.recfmt = cpu_to_le16(NVME_RDMA_CM_FMT_1_0); + rej.sts = cpu_to_le16(status); + + return rdma_reject(cm_id, (void *)&rej, sizeof(rej)); +} + +static struct nvmet_rdma_queue * +nvmet_rdma_alloc_queue(struct nvmet_rdma_device *ndev, + struct rdma_cm_id *cm_id, + struct rdma_cm_event *event) +{ + struct nvmet_rdma_queue *queue; + int ret; + + queue = kzalloc(sizeof(*queue), GFP_KERNEL); + if (!queue) { + ret = NVME_RDMA_CM_NO_RSC; + goto out_reject; + } + + ret = nvmet_sq_init(&queue->nvme_sq); + if (ret) + goto out_free_queue; + + ret = nvmet_rdma_parse_cm_connect_req(&event->param.conn, queue); + if (ret) + goto out_destroy_sq; + + /* + * Schedules the actual release because calling rdma_destroy_id from + * inside a CM callback would trigger a deadlock. (great API design..) + */ + INIT_WORK(&queue->release_work, nvmet_rdma_release_queue_work); + queue->dev = ndev; + queue->cm_id = cm_id; + + spin_lock_init(&queue->state_lock); + queue->state = NVMET_RDMA_Q_CONNECTING; + INIT_LIST_HEAD(&queue->rsp_wait_list); + INIT_LIST_HEAD(&queue->rsp_wr_wait_list); + spin_lock_init(&queue->rsp_wr_wait_lock); + INIT_LIST_HEAD(&queue->free_rsps); + spin_lock_init(&queue->rsps_lock); + + queue->idx = ida_simple_get(&nvmet_rdma_queue_ida, 0, 0, GFP_KERNEL); + if (queue->idx < 0) { + ret = NVME_RDMA_CM_NO_RSC; + goto out_free_queue; + } + + ret = nvmet_rdma_alloc_rsps(queue); + if (ret) { + ret = NVME_RDMA_CM_NO_RSC; + goto out_ida_remove; + } + + if (!ndev->srq) { + queue->cmds = nvmet_rdma_alloc_cmds(ndev, + queue->recv_queue_size, + !queue->host_qid); + if (IS_ERR(queue->cmds)) { + ret = NVME_RDMA_CM_NO_RSC; + goto out_free_responses; + } + } + + ret = nvmet_rdma_create_queue_ib(queue); + if (ret) { + pr_err("%s: creating RDMA queue failed (%d).\n", + __func__, ret); + ret = NVME_RDMA_CM_NO_RSC; + goto out_free_cmds; + } + + return queue; + +out_free_cmds: + if (!ndev->srq) { + nvmet_rdma_free_cmds(queue->dev, queue->cmds, + queue->recv_queue_size, + !queue->host_qid); + } +out_free_responses: + nvmet_rdma_free_rsps(queue); +out_ida_remove: + ida_simple_remove(&nvmet_rdma_queue_ida, queue->idx); +out_destroy_sq: + nvmet_sq_destroy(&queue->nvme_sq); +out_free_queue: + kfree(queue); +out_reject: + nvmet_rdma_cm_reject(cm_id, ret); + return NULL; +} + +static void nvmet_rdma_qp_event(struct ib_event *event, void *priv) +{ + struct nvmet_rdma_queue *queue = priv; + + switch (event->event) { + case IB_EVENT_COMM_EST: + rdma_notify(queue->cm_id, event->event); + break; + default: + pr_err("received unrecognized IB QP event %d\n", event->event); + break; + } +} + +static int nvmet_rdma_cm_accept(struct rdma_cm_id *cm_id, + struct nvmet_rdma_queue *queue, + struct rdma_conn_param *p) +{ + struct rdma_conn_param param = { }; + struct nvme_rdma_cm_rep priv = { }; + int ret = -ENOMEM; + + param.rnr_retry_count = 7; + param.flow_control = 1; + param.initiator_depth = min_t(u8, p->initiator_depth, + queue->dev->device->attrs.max_qp_init_rd_atom); + param.private_data = &priv; + param.private_data_len = sizeof(priv); + priv.recfmt = cpu_to_le16(NVME_RDMA_CM_FMT_1_0); + priv.crqsize = cpu_to_le16(queue->recv_queue_size); + + ret = rdma_accept(cm_id, ¶m); + if (ret) + pr_err("rdma_accept failed (error code = %d)\n", ret); + + return ret; +} + +static int nvmet_rdma_queue_connect(struct rdma_cm_id *cm_id, + struct rdma_cm_event *event) +{ + struct nvmet_rdma_device *ndev; + struct nvmet_rdma_queue *queue; + int ret = -EINVAL; + + ndev = nvmet_rdma_find_get_device(cm_id); + if (!ndev) { + pr_err("no client data!\n"); + nvmet_rdma_cm_reject(cm_id, NVME_RDMA_CM_NO_RSC); + return -ECONNREFUSED; + } + + queue = nvmet_rdma_alloc_queue(ndev, cm_id, event); + if (!queue) { + ret = -ENOMEM; + goto put_device; + } + queue->port = cm_id->context; + + ret = nvmet_rdma_cm_accept(cm_id, queue, &event->param.conn); + if (ret) + goto release_queue; + + mutex_lock(&nvmet_rdma_queue_mutex); + list_add_tail(&queue->queue_list, &nvmet_rdma_queue_list); + mutex_unlock(&nvmet_rdma_queue_mutex); + + return 0; + +release_queue: + nvmet_rdma_free_queue(queue); +put_device: + kref_put(&ndev->ref, nvmet_rdma_free_dev); + + return ret; +} + +static void nvmet_rdma_queue_established(struct nvmet_rdma_queue *queue) +{ + unsigned long flags; + + spin_lock_irqsave(&queue->state_lock, flags); + if (queue->state != NVMET_RDMA_Q_CONNECTING) { + pr_warn("trying to establish a connected queue\n"); + goto out_unlock; + } + queue->state = NVMET_RDMA_Q_LIVE; + + while (!list_empty(&queue->rsp_wait_list)) { + struct nvmet_rdma_rsp *cmd; + + cmd = list_first_entry(&queue->rsp_wait_list, + struct nvmet_rdma_rsp, wait_list); + list_del(&cmd->wait_list); + + spin_unlock_irqrestore(&queue->state_lock, flags); + nvmet_rdma_handle_command(queue, cmd); + spin_lock_irqsave(&queue->state_lock, flags); + } + +out_unlock: + spin_unlock_irqrestore(&queue->state_lock, flags); +} + +static void __nvmet_rdma_queue_disconnect(struct nvmet_rdma_queue *queue) +{ + bool disconnect = false; + unsigned long flags; + + pr_debug("cm_id= %p queue->state= %d\n", queue->cm_id, queue->state); + + spin_lock_irqsave(&queue->state_lock, flags); + switch (queue->state) { + case NVMET_RDMA_Q_CONNECTING: + case NVMET_RDMA_Q_LIVE: + disconnect = true; + queue->state = NVMET_RDMA_Q_DISCONNECTING; + break; + case NVMET_RDMA_Q_DISCONNECTING: + break; + } + spin_unlock_irqrestore(&queue->state_lock, flags); + + if (disconnect) { + rdma_disconnect(queue->cm_id); + ib_drain_qp(queue->cm_id->qp); + schedule_work(&queue->release_work); + } +} + +static void nvmet_rdma_queue_disconnect(struct nvmet_rdma_queue *queue) +{ + bool disconnect = false; + + mutex_lock(&nvmet_rdma_queue_mutex); + if (!list_empty(&queue->queue_list)) { + list_del_init(&queue->queue_list); + disconnect = true; + } + mutex_unlock(&nvmet_rdma_queue_mutex); + + if (disconnect) + __nvmet_rdma_queue_disconnect(queue); +} + +static void nvmet_rdma_queue_connect_fail(struct rdma_cm_id *cm_id, + struct nvmet_rdma_queue *queue) +{ + WARN_ON_ONCE(queue->state != NVMET_RDMA_Q_CONNECTING); + + pr_err("failed to connect queue\n"); + schedule_work(&queue->release_work); +} + +static int nvmet_rdma_cm_handler(struct rdma_cm_id *cm_id, + struct rdma_cm_event *event) +{ + struct nvmet_rdma_queue *queue = NULL; + int ret = 0; + + if (cm_id->qp) + queue = cm_id->qp->qp_context; + + pr_debug("%s (%d): status %d id %p\n", + rdma_event_msg(event->event), event->event, + event->status, cm_id); + + switch (event->event) { + case RDMA_CM_EVENT_CONNECT_REQUEST: + ret = nvmet_rdma_queue_connect(cm_id, event); + break; + case RDMA_CM_EVENT_ESTABLISHED: + nvmet_rdma_queue_established(queue); + break; + case RDMA_CM_EVENT_ADDR_CHANGE: + case RDMA_CM_EVENT_DISCONNECTED: + case RDMA_CM_EVENT_DEVICE_REMOVAL: + case RDMA_CM_EVENT_TIMEWAIT_EXIT: + /* + * We can get the device removal callback even for a + * CM ID that we aren't actually using. In that case + * the context pointer is NULL, so we shouldn't try + * to disconnect a non-existing queue. But we also + * need to return 1 so that the core will destroy + * it's own ID. What a great API design.. + */ + if (queue) + nvmet_rdma_queue_disconnect(queue); + else + ret = 1; + break; + case RDMA_CM_EVENT_REJECTED: + case RDMA_CM_EVENT_UNREACHABLE: + case RDMA_CM_EVENT_CONNECT_ERROR: + nvmet_rdma_queue_connect_fail(cm_id, queue); + break; + default: + pr_err("received unrecognized RDMA CM event %d\n", + event->event); + break; + } + + return ret; +} + +static void nvmet_rdma_delete_ctrl(struct nvmet_ctrl *ctrl) +{ + struct nvmet_rdma_queue *queue; + +restart: + mutex_lock(&nvmet_rdma_queue_mutex); + list_for_each_entry(queue, &nvmet_rdma_queue_list, queue_list) { + if (queue->nvme_sq.ctrl == ctrl) { + list_del_init(&queue->queue_list); + mutex_unlock(&nvmet_rdma_queue_mutex); + + __nvmet_rdma_queue_disconnect(queue); + goto restart; + } + } + mutex_unlock(&nvmet_rdma_queue_mutex); +} + +static int nvmet_rdma_add_port(struct nvmet_port *port) +{ + struct rdma_cm_id *cm_id; + struct sockaddr_in addr_in; + u16 port_in; + int ret; + + switch (port->disc_addr.adrfam) { + case NVMF_ADDR_FAMILY_IP4: + break; + default: + pr_err("address family %d not supported\n", + port->disc_addr.adrfam); + return -EINVAL; + } + + ret = kstrtou16(port->disc_addr.trsvcid, 0, &port_in); + if (ret) + return ret; + + addr_in.sin_family = AF_INET; + addr_in.sin_addr.s_addr = in_aton(port->disc_addr.traddr); + addr_in.sin_port = htons(port_in); + + cm_id = rdma_create_id(&init_net, nvmet_rdma_cm_handler, port, + RDMA_PS_TCP, IB_QPT_RC); + if (IS_ERR(cm_id)) { + pr_err("CM ID creation failed\n"); + return PTR_ERR(cm_id); + } + + ret = rdma_bind_addr(cm_id, (struct sockaddr *)&addr_in); + if (ret) { + pr_err("binding CM ID to %pISpc failed (%d)\n", &addr_in, ret); + goto out_destroy_id; + } + + ret = rdma_listen(cm_id, 128); + if (ret) { + pr_err("listening to %pISpc failed (%d)\n", &addr_in, ret); + goto out_destroy_id; + } + + pr_info("enabling port %d (%pISpc)\n", + le16_to_cpu(port->disc_addr.portid), &addr_in); + port->priv = cm_id; + return 0; + +out_destroy_id: + rdma_destroy_id(cm_id); + return ret; +} + +static void nvmet_rdma_remove_port(struct nvmet_port *port) +{ + struct rdma_cm_id *cm_id = port->priv; + + rdma_destroy_id(cm_id); +} + +static struct nvmet_fabrics_ops nvmet_rdma_ops = { + .owner = THIS_MODULE, + .type = NVMF_TRTYPE_RDMA, + .sqe_inline_size = NVMET_RDMA_INLINE_DATA_SIZE, + .msdbd = 1, + .has_keyed_sgls = 1, + .add_port = nvmet_rdma_add_port, + .remove_port = nvmet_rdma_remove_port, + .queue_response = nvmet_rdma_queue_response, + .delete_ctrl = nvmet_rdma_delete_ctrl, +}; + +static int __init nvmet_rdma_init(void) +{ + return nvmet_register_transport(&nvmet_rdma_ops); +} + +static void __exit nvmet_rdma_exit(void) +{ + struct nvmet_rdma_queue *queue; + + nvmet_unregister_transport(&nvmet_rdma_ops); + + flush_scheduled_work(); + + mutex_lock(&nvmet_rdma_queue_mutex); + while ((queue = list_first_entry_or_null(&nvmet_rdma_queue_list, + struct nvmet_rdma_queue, queue_list))) { + list_del_init(&queue->queue_list); + + mutex_unlock(&nvmet_rdma_queue_mutex); + __nvmet_rdma_queue_disconnect(queue); + mutex_lock(&nvmet_rdma_queue_mutex); + } + mutex_unlock(&nvmet_rdma_queue_mutex); + + flush_scheduled_work(); + ida_destroy(&nvmet_rdma_queue_ida); +} + +module_init(nvmet_rdma_init); +module_exit(nvmet_rdma_exit); + +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("nvmet-transport-1"); /* 1 == NVMF_TRTYPE_RDMA */ |