/* * Copyright (c) 2006 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 <linux/kernel.h> #include "rds.h" #include "rdma.h" #include "ib.h" /* * This is stored as mr->r_trans_private. */ struct rds_ib_mr { struct rds_ib_device *device; struct rds_ib_mr_pool *pool; struct ib_fmr *fmr; struct list_head list; unsigned int remap_count; struct scatterlist *sg; unsigned int sg_len; u64 *dma; int sg_dma_len; }; /* * Our own little FMR pool */ struct rds_ib_mr_pool { struct mutex flush_lock; /* serialize fmr invalidate */ struct work_struct flush_worker; /* flush worker */ spinlock_t list_lock; /* protect variables below */ atomic_t item_count; /* total # of MRs */ atomic_t dirty_count; /* # dirty of MRs */ struct list_head drop_list; /* MRs that have reached their max_maps limit */ struct list_head free_list; /* unused MRs */ struct list_head clean_list; /* unused & unamapped MRs */ atomic_t free_pinned; /* memory pinned by free MRs */ unsigned long max_items; unsigned long max_items_soft; unsigned long max_free_pinned; struct ib_fmr_attr fmr_attr; }; static int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool, int free_all); static void rds_ib_teardown_mr(struct rds_ib_mr *ibmr); static void rds_ib_mr_pool_flush_worker(struct work_struct *work); static struct rds_ib_device *rds_ib_get_device(__be32 ipaddr) { struct rds_ib_device *rds_ibdev; struct rds_ib_ipaddr *i_ipaddr; list_for_each_entry(rds_ibdev, &rds_ib_devices, list) { spin_lock_irq(&rds_ibdev->spinlock); list_for_each_entry(i_ipaddr, &rds_ibdev->ipaddr_list, list) { if (i_ipaddr->ipaddr == ipaddr) { spin_unlock_irq(&rds_ibdev->spinlock); return rds_ibdev; } } spin_unlock_irq(&rds_ibdev->spinlock); } return NULL; } static int rds_ib_add_ipaddr(struct rds_ib_device *rds_ibdev, __be32 ipaddr) { struct rds_ib_ipaddr *i_ipaddr; i_ipaddr = kmalloc(sizeof *i_ipaddr, GFP_KERNEL); if (!i_ipaddr) return -ENOMEM; i_ipaddr->ipaddr = ipaddr; spin_lock_irq(&rds_ibdev->spinlock); list_add_tail(&i_ipaddr->list, &rds_ibdev->ipaddr_list); spin_unlock_irq(&rds_ibdev->spinlock); return 0; } static void rds_ib_remove_ipaddr(struct rds_ib_device *rds_ibdev, __be32 ipaddr) { struct rds_ib_ipaddr *i_ipaddr, *next; spin_lock_irq(&rds_ibdev->spinlock); list_for_each_entry_safe(i_ipaddr, next, &rds_ibdev->ipaddr_list, list) { if (i_ipaddr->ipaddr == ipaddr) { list_del(&i_ipaddr->list); kfree(i_ipaddr); break; } } spin_unlock_irq(&rds_ibdev->spinlock); } int rds_ib_update_ipaddr(struct rds_ib_device *rds_ibdev, __be32 ipaddr) { struct rds_ib_device *rds_ibdev_old; rds_ibdev_old = rds_ib_get_device(ipaddr); if (rds_ibdev_old) rds_ib_remove_ipaddr(rds_ibdev_old, ipaddr); return rds_ib_add_ipaddr(rds_ibdev, ipaddr); } void rds_ib_add_conn(struct rds_ib_device *rds_ibdev, struct rds_connection *conn) { struct rds_ib_connection *ic = conn->c_transport_data; /* conn was previously on the nodev_conns_list */ spin_lock_irq(&ib_nodev_conns_lock); BUG_ON(list_empty(&ib_nodev_conns)); BUG_ON(list_empty(&ic->ib_node)); list_del(&ic->ib_node); spin_lock_irq(&rds_ibdev->spinlock); list_add_tail(&ic->ib_node, &rds_ibdev->conn_list); spin_unlock_irq(&rds_ibdev->spinlock); spin_unlock_irq(&ib_nodev_conns_lock); ic->rds_ibdev = rds_ibdev; } void rds_ib_remove_conn(struct rds_ib_device *rds_ibdev, struct rds_connection *conn) { struct rds_ib_connection *ic = conn->c_transport_data; /* place conn on nodev_conns_list */ spin_lock(&ib_nodev_conns_lock); spin_lock_irq(&rds_ibdev->spinlock); BUG_ON(list_empty(&ic->ib_node)); list_del(&ic->ib_node); spin_unlock_irq(&rds_ibdev->spinlock); list_add_tail(&ic->ib_node, &ib_nodev_conns); spin_unlock(&ib_nodev_conns_lock); ic->rds_ibdev = NULL; } void __rds_ib_destroy_conns(struct list_head *list, spinlock_t *list_lock) { struct rds_ib_connection *ic, *_ic; LIST_HEAD(tmp_list); /* avoid calling conn_destroy with irqs off */ spin_lock_irq(list_lock); list_splice(list, &tmp_list); INIT_LIST_HEAD(list); spin_unlock_irq(list_lock); list_for_each_entry_safe(ic, _ic, &tmp_list, ib_node) { if (ic->conn->c_passive) rds_conn_destroy(ic->conn->c_passive); rds_conn_destroy(ic->conn); } } struct rds_ib_mr_pool *rds_ib_create_mr_pool(struct rds_ib_device *rds_ibdev) { struct rds_ib_mr_pool *pool; pool = kzalloc(sizeof(*pool), GFP_KERNEL); if (!pool) return ERR_PTR(-ENOMEM); INIT_LIST_HEAD(&pool->free_list); INIT_LIST_HEAD(&pool->drop_list); INIT_LIST_HEAD(&pool->clean_list); mutex_init(&pool->flush_lock); spin_lock_init(&pool->list_lock); INIT_WORK(&pool->flush_worker, rds_ib_mr_pool_flush_worker); pool->fmr_attr.max_pages = fmr_message_size; pool->fmr_attr.max_maps = rds_ibdev->fmr_max_remaps; pool->fmr_attr.page_shift = rds_ibdev->fmr_page_shift; pool->max_free_pinned = rds_ibdev->max_fmrs * fmr_message_size / 4; /* We never allow more than max_items MRs to be allocated. * When we exceed more than max_items_soft, we start freeing * items more aggressively. * Make sure that max_items > max_items_soft > max_items / 2 */ pool->max_items_soft = rds_ibdev->max_fmrs * 3 / 4; pool->max_items = rds_ibdev->max_fmrs; return pool; } void rds_ib_get_mr_info(struct rds_ib_device *rds_ibdev, struct rds_info_rdma_connection *iinfo) { struct rds_ib_mr_pool *pool = rds_ibdev->mr_pool; iinfo->rdma_mr_max = pool->max_items; iinfo->rdma_mr_size = pool->fmr_attr.max_pages; } void rds_ib_destroy_mr_pool(struct rds_ib_mr_pool *pool) { flush_workqueue(rds_wq); rds_ib_flush_mr_pool(pool, 1); BUG_ON(atomic_read(&pool->item_count)); BUG_ON(atomic_read(&pool->free_pinned)); kfree(pool); } static inline struct rds_ib_mr *rds_ib_reuse_fmr(struct rds_ib_mr_pool *pool) { struct rds_ib_mr *ibmr = NULL; unsigned long flags; spin_lock_irqsave(&pool->list_lock, flags); if (!list_empty(&pool->clean_list)) { ibmr = list_entry(pool->clean_list.next, struct rds_ib_mr, list); list_del_init(&ibmr->list); } spin_unlock_irqrestore(&pool->list_lock, flags); return ibmr; } static struct rds_ib_mr *rds_ib_alloc_fmr(struct rds_ib_device *rds_ibdev) { struct rds_ib_mr_pool *pool = rds_ibdev->mr_pool; struct rds_ib_mr *ibmr = NULL; int err = 0, iter = 0; while (1) { ibmr = rds_ib_reuse_fmr(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) { rds_ib_stats_inc(s_ib_rdma_mr_pool_depleted); return ERR_PTR(-EAGAIN); } /* We do have some empty MRs. Flush them out. */ rds_ib_stats_inc(s_ib_rdma_mr_pool_wait); rds_ib_flush_mr_pool(pool, 0); } ibmr = kzalloc(sizeof(*ibmr), GFP_KERNEL); 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), &pool->fmr_attr); if (IS_ERR(ibmr->fmr)) { err = PTR_ERR(ibmr->fmr); ibmr->fmr = NULL; printk(KERN_WARNING "RDS/IB: ib_alloc_fmr failed (err=%d)\n", err); goto out_no_cigar; } rds_ib_stats_inc(s_ib_rdma_mr_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); } static 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)) { printk(KERN_WARNING "RDS/IB: dma_map_sg failed!\n"); 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 & ~rds_ibdev->fmr_page_mask) { if (i > 0) return -EINVAL; else ++page_cnt; } if ((dma_addr + dma_len) & ~rds_ibdev->fmr_page_mask) { if (i < sg_dma_len - 1) return -EINVAL; else ++page_cnt; } len += dma_len; } page_cnt += len >> rds_ibdev->fmr_page_shift; if (page_cnt > fmr_message_size) return -EINVAL; dma_pages = kmalloc(sizeof(u64) * page_cnt, GFP_ATOMIC); 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 += rds_ibdev->fmr_page_size) dma_pages[page_cnt++] = (dma_addr & rds_ibdev->fmr_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++; rds_ib_stats_inc(s_ib_rdma_mr_used); ret = 0; out: kfree(dma_pages); return ret; } void rds_ib_sync_mr(void *trans_private, int direction) { struct rds_ib_mr *ibmr = trans_private; struct rds_ib_device *rds_ibdev = ibmr->device; switch (direction) { case DMA_FROM_DEVICE: ib_dma_sync_sg_for_cpu(rds_ibdev->dev, ibmr->sg, ibmr->sg_dma_len, DMA_BIDIRECTIONAL); break; case DMA_TO_DEVICE: ib_dma_sync_sg_for_device(rds_ibdev->dev, ibmr->sg, ibmr->sg_dma_len, DMA_BIDIRECTIONAL); break; } } static void __rds_ib_teardown_mr(struct rds_ib_mr *ibmr) { struct rds_ib_device *rds_ibdev = ibmr->device; if (ibmr->sg_dma_len) { ib_dma_unmap_sg(rds_ibdev->dev, ibmr->sg, ibmr->sg_len, DMA_BIDIRECTIONAL); ibmr->sg_dma_len = 0; } /* Release the s/g list */ if (ibmr->sg_len) { unsigned int i; for (i = 0; i < ibmr->sg_len; ++i) { struct page *page = sg_page(&ibmr->sg[i]); /* FIXME we need a way to tell a r/w MR * from a r/o MR */ set_page_dirty(page); put_page(page); } kfree(ibmr->sg); ibmr->sg = NULL; ibmr->sg_len = 0; } } static void rds_ib_teardown_mr(struct rds_ib_mr *ibmr) { unsigned int pinned = ibmr->sg_len; __rds_ib_teardown_mr(ibmr); if (pinned) { struct rds_ib_device *rds_ibdev = ibmr->device; struct rds_ib_mr_pool *pool = rds_ibdev->mr_pool; atomic_sub(pinned, &pool->free_pinned); } } static inline unsigned int rds_ib_flush_goal(struct rds_ib_mr_pool *pool, int free_all) { unsigned int item_count; item_count = atomic_read(&pool->item_count); if (free_all) return item_count; return 0; } /* * Flush our pool of MRs. * At a minimum, all currently unused MRs are unmapped. * If the number of MRs allocated exceeds the limit, we also try * to free as many MRs as needed to get back to this limit. */ static int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool, int free_all) { struct rds_ib_mr *ibmr, *next; LIST_HEAD(unmap_list); LIST_HEAD(fmr_list); unsigned long unpinned = 0; unsigned long flags; unsigned int nfreed = 0, ncleaned = 0, free_goal; int ret = 0; rds_ib_stats_inc(s_ib_rdma_mr_pool_flush); mutex_lock(&pool->flush_lock); spin_lock_irqsave(&pool->list_lock, flags); /* Get the list of all MRs to be dropped. Ordering matters - * we want to put drop_list ahead of free_list. */ list_splice_init(&pool->free_list, &unmap_list); list_splice_init(&pool->drop_list, &unmap_list); if (free_all) list_splice_init(&pool->clean_list, &unmap_list); spin_unlock_irqrestore(&pool->list_lock, flags); free_goal = rds_ib_flush_goal(pool, free_all); if (list_empty(&unmap_list)) goto out; /* String all ib_mr's onto one list and hand them to ib_unmap_fmr */ list_for_each_entry(ibmr, &unmap_list, list) list_add(&ibmr->fmr->list, &fmr_list); ret = ib_unmap_fmr(&fmr_list); if (ret) printk(KERN_WARNING "RDS/IB: ib_unmap_fmr failed (err=%d)\n", ret); /* Now we can destroy the DMA mapping and unpin any pages */ list_for_each_entry_safe(ibmr, next, &unmap_list, list) { unpinned += ibmr->sg_len; __rds_ib_teardown_mr(ibmr); if (nfreed < free_goal || ibmr->remap_count >= pool->fmr_attr.max_maps) { rds_ib_stats_inc(s_ib_rdma_mr_free); list_del(&ibmr->list); ib_dealloc_fmr(ibmr->fmr); kfree(ibmr); nfreed++; } ncleaned++; } spin_lock_irqsave(&pool->list_lock, flags); list_splice(&unmap_list, &pool->clean_list); spin_unlock_irqrestore(&pool->list_lock, flags); atomic_sub(unpinned, &pool->free_pinned); atomic_sub(ncleaned, &pool->dirty_count); atomic_sub(nfreed, &pool->item_count); out: mutex_unlock(&pool->flush_lock); return ret; } static void rds_ib_mr_pool_flush_worker(struct work_struct *work) { struct rds_ib_mr_pool *pool = container_of(work, struct rds_ib_mr_pool, flush_worker); rds_ib_flush_mr_pool(pool, 0); } void rds_ib_free_mr(void *trans_private, int invalidate) { struct rds_ib_mr *ibmr = trans_private; struct rds_ib_device *rds_ibdev = ibmr->device; struct rds_ib_mr_pool *pool = rds_ibdev->mr_pool; unsigned long flags; rdsdebug("RDS/IB: free_mr nents %u\n", ibmr->sg_len); /* Return it to the pool's free list */ spin_lock_irqsave(&pool->list_lock, flags); if (ibmr->remap_count >= pool->fmr_attr.max_maps) list_add(&ibmr->list, &pool->drop_list); else list_add(&ibmr->list, &pool->free_list); atomic_add(ibmr->sg_len, &pool->free_pinned); atomic_inc(&pool->dirty_count); spin_unlock_irqrestore(&pool->list_lock, flags); /* 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 / 10) queue_work(rds_wq, &pool->flush_worker); if (invalidate) { if (likely(!in_interrupt())) { rds_ib_flush_mr_pool(pool, 0); } else { /* We get here if the user created a MR marked * as use_once and invalidate at the same time. */ queue_work(rds_wq, &pool->flush_worker); } } } void rds_ib_flush_mrs(void) { struct rds_ib_device *rds_ibdev; list_for_each_entry(rds_ibdev, &rds_ib_devices, list) { struct rds_ib_mr_pool *pool = rds_ibdev->mr_pool; if (pool) rds_ib_flush_mr_pool(pool, 0); } } void *rds_ib_get_mr(struct scatterlist *sg, unsigned long nents, struct rds_sock *rs, u32 *key_ret) { struct rds_ib_device *rds_ibdev; struct rds_ib_mr *ibmr = NULL; int ret; rds_ibdev = rds_ib_get_device(rs->rs_bound_addr); if (!rds_ibdev) { ret = -ENODEV; goto out; } if (!rds_ibdev->mr_pool) { ret = -ENODEV; goto out; } ibmr = rds_ib_alloc_fmr(rds_ibdev); if (IS_ERR(ibmr)) return ibmr; ret = rds_ib_map_fmr(rds_ibdev, ibmr, sg, nents); if (ret == 0) *key_ret = ibmr->fmr->rkey; else printk(KERN_WARNING "RDS/IB: map_fmr failed (errno=%d)\n", ret); ibmr->device = rds_ibdev; out: if (ret) { if (ibmr) rds_ib_free_mr(ibmr, 0); ibmr = ERR_PTR(ret); } return ibmr; }