diff options
Diffstat (limited to 'net/rds/ib_fmr.c')
-rw-r--r-- | net/rds/ib_fmr.c | 217 |
1 files changed, 217 insertions, 0 deletions
diff --git a/net/rds/ib_fmr.c b/net/rds/ib_fmr.c new file mode 100644 index 0000000..d4f200d --- /dev/null +++ b/net/rds/ib_fmr.c @@ -0,0 +1,217 @@ +/* + * 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" + +struct rds_ib_mr *rds_ib_alloc_fmr(struct rds_ib_device *rds_ibdev, int npages) +{ + struct rds_ib_mr_pool *pool; + struct rds_ib_mr *ibmr = NULL; + int err = 0, iter = 0; + + if (npages <= RDS_MR_8K_MSG_SIZE) + pool = rds_ibdev->mr_8k_pool; + else + pool = rds_ibdev->mr_1m_pool; + + if (atomic_read(&pool->dirty_count) >= pool->max_items / 10) + queue_delayed_work(rds_ib_mr_wq, &pool->flush_worker, 10); + + /* Switch pools if one of the pool is reaching upper limit */ + if (atomic_read(&pool->dirty_count) >= pool->max_items * 9 / 10) { + if (pool->pool_type == RDS_IB_MR_8K_POOL) + pool = rds_ibdev->mr_1m_pool; + else + pool = rds_ibdev->mr_8k_pool; + } + + while (1) { + ibmr = rds_ib_reuse_mr(pool); + if (ibmr) + return ibmr; + + /* No clean MRs - now we have the choice of either + * allocating a fresh MR up to the limit imposed by the + * driver, or flush any dirty unused MRs. + * We try to avoid stalling in the send path if possible, + * so we allocate as long as we're allowed to. + * + * We're fussy with enforcing the FMR limit, though. If the + * driver tells us we can't use more than N fmrs, we shouldn't + * start arguing with it + */ + if (atomic_inc_return(&pool->item_count) <= pool->max_items) + break; + + atomic_dec(&pool->item_count); + + if (++iter > 2) { + if (pool->pool_type == RDS_IB_MR_8K_POOL) + rds_ib_stats_inc(s_ib_rdma_mr_8k_pool_depleted); + else + rds_ib_stats_inc(s_ib_rdma_mr_1m_pool_depleted); + return ERR_PTR(-EAGAIN); + } + + /* We do have some empty MRs. Flush them out. */ + if (pool->pool_type == RDS_IB_MR_8K_POOL) + rds_ib_stats_inc(s_ib_rdma_mr_8k_pool_wait); + else + rds_ib_stats_inc(s_ib_rdma_mr_1m_pool_wait); + rds_ib_flush_mr_pool(pool, 0, &ibmr); + if (ibmr) + return ibmr; + } + + ibmr = kzalloc_node(sizeof(*ibmr), GFP_KERNEL, + rdsibdev_to_node(rds_ibdev)); + if (!ibmr) { + err = -ENOMEM; + goto out_no_cigar; + } + + ibmr->fmr = ib_alloc_fmr(rds_ibdev->pd, + (IB_ACCESS_LOCAL_WRITE | + IB_ACCESS_REMOTE_READ | + IB_ACCESS_REMOTE_WRITE | + IB_ACCESS_REMOTE_ATOMIC), + &pool->fmr_attr); + if (IS_ERR(ibmr->fmr)) { + err = PTR_ERR(ibmr->fmr); + ibmr->fmr = NULL; + pr_warn("RDS/IB: %s failed (err=%d)\n", __func__, err); + 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); + + return ibmr; + +out_no_cigar: + if (ibmr) { + if (ibmr->fmr) + ib_dealloc_fmr(ibmr->fmr); + kfree(ibmr); + } + atomic_dec(&pool->item_count); + return ERR_PTR(err); +} + +int rds_ib_map_fmr(struct rds_ib_device *rds_ibdev, struct rds_ib_mr *ibmr, + struct scatterlist *sg, unsigned int nents) +{ + struct ib_device *dev = rds_ibdev->dev; + struct scatterlist *scat = sg; + u64 io_addr = 0; + u64 *dma_pages; + u32 len; + int page_cnt, sg_dma_len; + int i, j; + int ret; + + sg_dma_len = ib_dma_map_sg(dev, sg, nents, DMA_BIDIRECTIONAL); + if (unlikely(!sg_dma_len)) { + pr_warn("RDS/IB: %s failed!\n", __func__); + return -EBUSY; + } + + len = 0; + page_cnt = 0; + + for (i = 0; i < sg_dma_len; ++i) { + unsigned int dma_len = ib_sg_dma_len(dev, &scat[i]); + u64 dma_addr = ib_sg_dma_address(dev, &scat[i]); + + if (dma_addr & ~PAGE_MASK) { + if (i > 0) + return -EINVAL; + else + ++page_cnt; + } + if ((dma_addr + dma_len) & ~PAGE_MASK) { + if (i < sg_dma_len - 1) + return -EINVAL; + else + ++page_cnt; + } + + len += dma_len; + } + + page_cnt += len >> PAGE_SHIFT; + if (page_cnt > ibmr->pool->fmr_attr.max_pages) + return -EINVAL; + + dma_pages = kmalloc_node(sizeof(u64) * page_cnt, GFP_ATOMIC, + rdsibdev_to_node(rds_ibdev)); + if (!dma_pages) + return -ENOMEM; + + page_cnt = 0; + for (i = 0; i < sg_dma_len; ++i) { + unsigned int dma_len = ib_sg_dma_len(dev, &scat[i]); + u64 dma_addr = ib_sg_dma_address(dev, &scat[i]); + + for (j = 0; j < dma_len; j += PAGE_SIZE) + dma_pages[page_cnt++] = + (dma_addr & PAGE_MASK) + j; + } + + ret = ib_map_phys_fmr(ibmr->fmr, dma_pages, page_cnt, io_addr); + if (ret) + goto out; + + /* Success - we successfully remapped the MR, so we can + * safely tear down the old mapping. + */ + rds_ib_teardown_mr(ibmr); + + ibmr->sg = scat; + ibmr->sg_len = nents; + ibmr->sg_dma_len = sg_dma_len; + ibmr->remap_count++; + + 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); + ret = 0; + +out: + kfree(dma_pages); + + return ret; +} |