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path: root/drivers/nvme/target/rdma.c
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Diffstat (limited to 'drivers/nvme/target/rdma.c')
-rw-r--r--drivers/nvme/target/rdma.c1497
1 files changed, 1497 insertions, 0 deletions
diff --git a/drivers/nvme/target/rdma.c b/drivers/nvme/target/rdma.c
new file mode 100644
index 000000000..1cbe6e053
--- /dev/null
+++ b/drivers/nvme/target/rdma.c
@@ -0,0 +1,1497 @@
+/*
+ * 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,
+ NVMET_RDMA_IN_DEVICE_REMOVAL,
+};
+
+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;
+
+ 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;
+ enum nvmet_rdma_queue_state state = queue->state;
+
+ nvmet_rdma_free_queue(queue);
+
+ if (state != NVMET_RDMA_IN_DEVICE_REMOVAL)
+ 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 plus 1
+ * req->hrqsize corresponds to our send queue size
+ */
+ queue->recv_queue_size = le16_to_cpu(req->hsqsize) + 1;
+ 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, &param);
+ 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:
+ queue->state = NVMET_RDMA_Q_DISCONNECTING;
+ case NVMET_RDMA_IN_DEVICE_REMOVAL:
+ disconnect = true;
+ 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);
+}
+
+/**
+ * nvme_rdma_device_removal() - Handle RDMA device removal
+ * @queue: nvmet rdma queue (cm id qp_context)
+ * @addr: nvmet address (cm_id context)
+ *
+ * DEVICE_REMOVAL event notifies us that the RDMA device is about
+ * to unplug so we should take care of destroying our RDMA resources.
+ * This event will be generated for each allocated cm_id.
+ *
+ * Note that this event can be generated on a normal queue cm_id
+ * and/or a device bound listener cm_id (where in this case
+ * queue will be null).
+ *
+ * we claim ownership on destroying the cm_id. For queues we move
+ * the queue state to NVMET_RDMA_IN_DEVICE_REMOVAL and for port
+ * we nullify the priv to prevent double cm_id destruction and destroying
+ * the cm_id implicitely by returning a non-zero rc to the callout.
+ */
+static int nvmet_rdma_device_removal(struct rdma_cm_id *cm_id,
+ struct nvmet_rdma_queue *queue)
+{
+ unsigned long flags;
+
+ if (!queue) {
+ struct nvmet_port *port = cm_id->context;
+
+ /*
+ * This is a listener cm_id. Make sure that
+ * future remove_port won't invoke a double
+ * cm_id destroy. use atomic xchg to make sure
+ * we don't compete with remove_port.
+ */
+ if (xchg(&port->priv, NULL) != cm_id)
+ return 0;
+ } else {
+ /*
+ * This is a queue cm_id. Make sure that
+ * release queue will not destroy the cm_id
+ * and schedule all ctrl queues removal (only
+ * if the queue is not disconnecting already).
+ */
+ spin_lock_irqsave(&queue->state_lock, flags);
+ if (queue->state != NVMET_RDMA_Q_DISCONNECTING)
+ queue->state = NVMET_RDMA_IN_DEVICE_REMOVAL;
+ spin_unlock_irqrestore(&queue->state_lock, flags);
+ nvmet_rdma_queue_disconnect(queue);
+ flush_scheduled_work();
+ }
+
+ /*
+ * We need to return 1 so that the core will destroy
+ * it's own ID. What a great API design..
+ */
+ return 1;
+}
+
+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_TIMEWAIT_EXIT:
+ nvmet_rdma_queue_disconnect(queue);
+ break;
+ case RDMA_CM_EVENT_DEVICE_REMOVAL:
+ ret = nvmet_rdma_device_removal(cm_id, queue);
+ 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 = xchg(&port->priv, NULL);
+
+ if (cm_id)
+ 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 */