1 files changed, 376 insertions, 0 deletions

diff --git a/net/rds/ib_frmr.c b/net/rds/ib_frmr.c
new file mode 100644
index 000000000000..93ff038ea9d1
--- /dev/null
+++ b/net/rds/ib_frmr.c
@@ -0,0 +1,376 @@
+/*
+ * Copyright (c) 2016 Oracle.  All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "ib_mr.h"
+
+static struct rds_ib_mr *rds_ib_alloc_frmr(struct rds_ib_device *rds_ibdev,
+                                           int npages)
+{
+        struct rds_ib_mr_pool *pool;
+        struct rds_ib_mr *ibmr = NULL;
+        struct rds_ib_frmr *frmr;
+        int err = 0;
+
+        if (npages <= RDS_MR_8K_MSG_SIZE)
+                pool = rds_ibdev->mr_8k_pool;
+        else
+                pool = rds_ibdev->mr_1m_pool;
+
+        ibmr = rds_ib_try_reuse_ibmr(pool);
+        if (ibmr)
+                return ibmr;
+
+        ibmr = kzalloc_node(sizeof(*ibmr), GFP_KERNEL,
+                            rdsibdev_to_node(rds_ibdev));
+        if (!ibmr) {
+                err = -ENOMEM;
+                goto out_no_cigar;
+        }
+
+        frmr = &ibmr->u.frmr;
+        frmr->mr = ib_alloc_mr(rds_ibdev->pd, IB_MR_TYPE_MEM_REG,
+                         pool->fmr_attr.max_pages);
+        if (IS_ERR(frmr->mr)) {
+                pr_warn("RDS/IB: %s failed to allocate MR", __func__);
+                goto out_no_cigar;
+        }
+
+        ibmr->pool = pool;
+        if (pool->pool_type == RDS_IB_MR_8K_POOL)
+                rds_ib_stats_inc(s_ib_rdma_mr_8k_alloc);
+        else
+                rds_ib_stats_inc(s_ib_rdma_mr_1m_alloc);
+
+        if (atomic_read(&pool->item_count) > pool->max_items_soft)
+                pool->max_items_soft = pool->max_items;
+
+        frmr->fr_state = FRMR_IS_FREE;
+        return ibmr;
+
+out_no_cigar:
+        kfree(ibmr);
+        atomic_dec(&pool->item_count);
+        return ERR_PTR(err);
+}
+
+static void rds_ib_free_frmr(struct rds_ib_mr *ibmr, bool drop)
+{
+        struct rds_ib_mr_pool *pool = ibmr->pool;
+
+        if (drop)
+                llist_add(&ibmr->llnode, &pool->drop_list);
+        else
+                llist_add(&ibmr->llnode, &pool->free_list);
+        atomic_add(ibmr->sg_len, &pool->free_pinned);
+        atomic_inc(&pool->dirty_count);
+
+        /* If we've pinned too many pages, request a flush */
+        if (atomic_read(&pool->free_pinned) >= pool->max_free_pinned ||
+            atomic_read(&pool->dirty_count) >= pool->max_items / 5)
+                queue_delayed_work(rds_ib_mr_wq, &pool->flush_worker, 10);
+}
+
+static int rds_ib_post_reg_frmr(struct rds_ib_mr *ibmr)
+{
+        struct rds_ib_frmr *frmr = &ibmr->u.frmr;
+        struct ib_send_wr *failed_wr;
+        struct ib_reg_wr reg_wr;
+        int ret;
+
+        while (atomic_dec_return(&ibmr->ic->i_fastreg_wrs) <= 0) {
+                atomic_inc(&ibmr->ic->i_fastreg_wrs);
+                cpu_relax();
+        }
+
+        ret = ib_map_mr_sg_zbva(frmr->mr, ibmr->sg, ibmr->sg_len, PAGE_SIZE);
+        if (unlikely(ret != ibmr->sg_len))
+                return ret < 0 ? ret : -EINVAL;
+
+        /* Perform a WR for the fast_reg_mr. Each individual page
+         * in the sg list is added to the fast reg page list and placed
+         * inside the fast_reg_mr WR.  The key used is a rolling 8bit
+         * counter, which should guarantee uniqueness.
+         */
+        ib_update_fast_reg_key(frmr->mr, ibmr->remap_count++);
+        frmr->fr_state = FRMR_IS_INUSE;
+
+        memset(&reg_wr, 0, sizeof(reg_wr));
+        reg_wr.wr.wr_id = (unsigned long)(void *)ibmr;
+        reg_wr.wr.opcode = IB_WR_REG_MR;
+        reg_wr.wr.num_sge = 0;
+        reg_wr.mr = frmr->mr;
+        reg_wr.key = frmr->mr->rkey;
+        reg_wr.access = IB_ACCESS_LOCAL_WRITE |
+                        IB_ACCESS_REMOTE_READ |
+                        IB_ACCESS_REMOTE_WRITE;
+        reg_wr.wr.send_flags = IB_SEND_SIGNALED;
+
+        failed_wr = &reg_wr.wr;
+        ret = ib_post_send(ibmr->ic->i_cm_id->qp, &reg_wr.wr, &failed_wr);
+        WARN_ON(failed_wr != &reg_wr.wr);
+        if (unlikely(ret)) {
+                /* Failure here can be because of -ENOMEM as well */
+                frmr->fr_state = FRMR_IS_STALE;
+                atomic_inc(&ibmr->ic->i_fastreg_wrs);
+                if (printk_ratelimit())
+                        pr_warn("RDS/IB: %s returned error(%d)\n",
+                                __func__, ret);
+        }
+        return ret;
+}
+
+static int rds_ib_map_frmr(struct rds_ib_device *rds_ibdev,
+                           struct rds_ib_mr_pool *pool,
+                           struct rds_ib_mr *ibmr,
+                           struct scatterlist *sg, unsigned int sg_len)
+{
+        struct ib_device *dev = rds_ibdev->dev;
+        struct rds_ib_frmr *frmr = &ibmr->u.frmr;
+        int i;
+        u32 len;
+        int ret = 0;
+
+        /* We want to teardown old ibmr values here and fill it up with
+         * new sg values
+         */
+        rds_ib_teardown_mr(ibmr);
+
+        ibmr->sg = sg;
+        ibmr->sg_len = sg_len;
+        ibmr->sg_dma_len = 0;
+        frmr->sg_byte_len = 0;
+        WARN_ON(ibmr->sg_dma_len);
+        ibmr->sg_dma_len = ib_dma_map_sg(dev, ibmr->sg, ibmr->sg_len,
+                                         DMA_BIDIRECTIONAL);
+        if (unlikely(!ibmr->sg_dma_len)) {
+                pr_warn("RDS/IB: %s failed!\n", __func__);
+                return -EBUSY;
+        }
+
+        frmr->sg_byte_len = 0;
+        frmr->dma_npages = 0;
+        len = 0;
+
+        ret = -EINVAL;
+        for (i = 0; i < ibmr->sg_dma_len; ++i) {
+                unsigned int dma_len = ib_sg_dma_len(dev, &ibmr->sg[i]);
+                u64 dma_addr = ib_sg_dma_address(dev, &ibmr->sg[i]);
+
+                frmr->sg_byte_len += dma_len;
+                if (dma_addr & ~PAGE_MASK) {
+                        if (i > 0)
+                                goto out_unmap;
+                        else
+                                ++frmr->dma_npages;
+                }
+
+                if ((dma_addr + dma_len) & ~PAGE_MASK) {
+                        if (i < ibmr->sg_dma_len - 1)
+                                goto out_unmap;
+                        else
+                                ++frmr->dma_npages;
+                }
+
+                len += dma_len;
+        }
+        frmr->dma_npages += len >> PAGE_SHIFT;
+
+        if (frmr->dma_npages > ibmr->pool->fmr_attr.max_pages) {
+                ret = -EMSGSIZE;
+                goto out_unmap;
+        }
+
+        ret = rds_ib_post_reg_frmr(ibmr);
+        if (ret)
+                goto out_unmap;
+
+        if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
+                rds_ib_stats_inc(s_ib_rdma_mr_8k_used);
+        else
+                rds_ib_stats_inc(s_ib_rdma_mr_1m_used);
+
+        return ret;
+
+out_unmap:
+        ib_dma_unmap_sg(rds_ibdev->dev, ibmr->sg, ibmr->sg_len,
+                        DMA_BIDIRECTIONAL);
+        ibmr->sg_dma_len = 0;
+        return ret;
+}
+
+static int rds_ib_post_inv(struct rds_ib_mr *ibmr)
+{
+        struct ib_send_wr *s_wr, *failed_wr;
+        struct rds_ib_frmr *frmr = &ibmr->u.frmr;
+        struct rdma_cm_id *i_cm_id = ibmr->ic->i_cm_id;
+        int ret = -EINVAL;
+
+        if (!i_cm_id || !i_cm_id->qp || !frmr->mr)
+                goto out;
+
+        if (frmr->fr_state != FRMR_IS_INUSE)
+                goto out;
+
+        while (atomic_dec_return(&ibmr->ic->i_fastreg_wrs) <= 0) {
+                atomic_inc(&ibmr->ic->i_fastreg_wrs);
+                cpu_relax();
+        }
+
+        frmr->fr_inv = true;
+        s_wr = &frmr->fr_wr;
+
+        memset(s_wr, 0, sizeof(*s_wr));
+        s_wr->wr_id = (unsigned long)(void *)ibmr;
+        s_wr->opcode = IB_WR_LOCAL_INV;
+        s_wr->ex.invalidate_rkey = frmr->mr->rkey;
+        s_wr->send_flags = IB_SEND_SIGNALED;
+
+        failed_wr = s_wr;
+        ret = ib_post_send(i_cm_id->qp, s_wr, &failed_wr);
+        WARN_ON(failed_wr != s_wr);
+        if (unlikely(ret)) {
+                frmr->fr_state = FRMR_IS_STALE;
+                frmr->fr_inv = false;
+                atomic_inc(&ibmr->ic->i_fastreg_wrs);
+                pr_err("RDS/IB: %s returned error(%d)\n", __func__, ret);
+                goto out;
+        }
+out:
+        return ret;
+}
+
+void rds_ib_mr_cqe_handler(struct rds_ib_connection *ic, struct ib_wc *wc)
+{
+        struct rds_ib_mr *ibmr = (void *)(unsigned long)wc->wr_id;
+        struct rds_ib_frmr *frmr = &ibmr->u.frmr;
+
+        if (wc->status != IB_WC_SUCCESS) {
+                frmr->fr_state = FRMR_IS_STALE;
+                if (rds_conn_up(ic->conn))
+                        rds_ib_conn_error(ic->conn,
+                                          "frmr completion <%pI4,%pI4> status %u(%s), vendor_err 0x%x, disconnecting and reconnecting\n",
+                                          &ic->conn->c_laddr,
+                                          &ic->conn->c_faddr,
+                                          wc->status,
+                                          ib_wc_status_msg(wc->status),
+                                          wc->vendor_err);
+        }
+
+        if (frmr->fr_inv) {
+                frmr->fr_state = FRMR_IS_FREE;
+                frmr->fr_inv = false;
+        }
+
+        atomic_inc(&ic->i_fastreg_wrs);
+}
+
+void rds_ib_unreg_frmr(struct list_head *list, unsigned int *nfreed,
+                       unsigned long *unpinned, unsigned int goal)
+{
+        struct rds_ib_mr *ibmr, *next;
+        struct rds_ib_frmr *frmr;
+        int ret = 0;
+        unsigned int freed = *nfreed;
+
+        /* String all ib_mr's onto one list and hand them to ib_unmap_fmr */
+        list_for_each_entry(ibmr, list, unmap_list) {
+                if (ibmr->sg_dma_len)
+                        ret |= rds_ib_post_inv(ibmr);
+        }
+        if (ret)
+                pr_warn("RDS/IB: %s failed (err=%d)\n", __func__, ret);
+
+        /* Now we can destroy the DMA mapping and unpin any pages */
+        list_for_each_entry_safe(ibmr, next, list, unmap_list) {
+                *unpinned += ibmr->sg_len;
+                frmr = &ibmr->u.frmr;
+                __rds_ib_teardown_mr(ibmr);
+                if (freed < goal || frmr->fr_state == FRMR_IS_STALE) {
+                        /* Don't de-allocate if the MR is not free yet */
+                        if (frmr->fr_state == FRMR_IS_INUSE)
+                                continue;
+
+                        if (ibmr->pool->pool_type == RDS_IB_MR_8K_POOL)
+                                rds_ib_stats_inc(s_ib_rdma_mr_8k_free);
+                        else
+                                rds_ib_stats_inc(s_ib_rdma_mr_1m_free);
+                        list_del(&ibmr->unmap_list);
+                        if (frmr->mr)
+                                ib_dereg_mr(frmr->mr);
+                        kfree(ibmr);
+                        freed++;
+                }
+        }
+        *nfreed = freed;
+}
+
+struct rds_ib_mr *rds_ib_reg_frmr(struct rds_ib_device *rds_ibdev,
+                                  struct rds_ib_connection *ic,
+                                  struct scatterlist *sg,
+                                  unsigned long nents, u32 *key)
+{
+        struct rds_ib_mr *ibmr = NULL;
+        struct rds_ib_frmr *frmr;
+        int ret;
+
+        do {
+                if (ibmr)
+                        rds_ib_free_frmr(ibmr, true);
+                ibmr = rds_ib_alloc_frmr(rds_ibdev, nents);
+                if (IS_ERR(ibmr))
+                        return ibmr;
+                frmr = &ibmr->u.frmr;
+        } while (frmr->fr_state != FRMR_IS_FREE);
+
+        ibmr->ic = ic;
+        ibmr->device = rds_ibdev;
+        ret = rds_ib_map_frmr(rds_ibdev, ibmr->pool, ibmr, sg, nents);
+        if (ret == 0) {
+                *key = frmr->mr->rkey;
+        } else {
+                rds_ib_free_frmr(ibmr, false);
+                ibmr = ERR_PTR(ret);
+        }
+
+        return ibmr;
+}
+
+void rds_ib_free_frmr_list(struct rds_ib_mr *ibmr)
+{
+        struct rds_ib_mr_pool *pool = ibmr->pool;
+        struct rds_ib_frmr *frmr = &ibmr->u.frmr;
+
+        if (frmr->fr_state == FRMR_IS_STALE)
+                llist_add(&ibmr->llnode, &pool->drop_list);
+        else
+                llist_add(&ibmr->llnode, &pool->free_list);
+}