From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by dpdk.org (Postfix) with ESMTP id 8235D1B6A1 for ; Sun, 8 Apr 2018 22:18:59 +0200 (CEST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 08 Apr 2018 13:18:58 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.48,424,1517904000"; d="scan'208";a="32059826" Received: from irvmail001.ir.intel.com ([163.33.26.43]) by orsmga008.jf.intel.com with ESMTP; 08 Apr 2018 13:18:54 -0700 Received: from sivswdev01.ir.intel.com (sivswdev01.ir.intel.com [10.237.217.45]) by irvmail001.ir.intel.com (8.14.3/8.13.6/MailSET/Hub) with ESMTP id w38KIsID021259; Sun, 8 Apr 2018 21:18:54 +0100 Received: from sivswdev01.ir.intel.com (localhost [127.0.0.1]) by sivswdev01.ir.intel.com with ESMTP id w38KIs03011349; Sun, 8 Apr 2018 21:18:54 +0100 Received: (from aburakov@localhost) by sivswdev01.ir.intel.com with LOCAL id w38KIsDd011345; Sun, 8 Apr 2018 21:18:54 +0100 From: Anatoly Burakov To: dev@dpdk.org Cc: keith.wiles@intel.com, jianfeng.tan@intel.com, andras.kovacs@ericsson.com, laszlo.vadkeri@ericsson.com, benjamin.walker@intel.com, bruce.richardson@intel.com, thomas@monjalon.net, konstantin.ananyev@intel.com, kuralamudhan.ramakrishnan@intel.com, louise.m.daly@intel.com, nelio.laranjeiro@6wind.com, yskoh@mellanox.com, pepperjo@japf.ch, jerin.jacob@caviumnetworks.com, hemant.agrawal@nxp.com, olivier.matz@6wind.com, shreyansh.jain@nxp.com, gowrishankar.m@linux.vnet.ibm.com Date: Sun, 8 Apr 2018 21:18:37 +0100 Message-Id: <62056b79db2739931cf525105cd31dafd982e153.1523218215.git.anatoly.burakov@intel.com> X-Mailer: git-send-email 1.7.0.7 In-Reply-To: References: In-Reply-To: References: Subject: [dpdk-dev] [PATCH v4 64/70] vfio: enable support for mem event callbacks X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 08 Apr 2018 20:19:00 -0000 Enable callbacks on first device attach, disable callbacks on last device attach. PPC64 IOMMU does memseg walk, which will cause a deadlock on trying to do it inside a callback, so provide a local, thread-unsafe copy of memseg walk. Signed-off-by: Anatoly Burakov --- Notes: v4: - Fix PPC64 memseg walk in callback - Check if registering callbacks succeeded v3: - Moved callbacks to attach/detach as opposed to init v4: - Fix PPC64 memseg walk in callback v3: - Moved callbacks to attach/detach as opposed to init lib/librte_eal/linuxapp/eal/eal_vfio.c | 133 +++++++++++++++++++++++++++++++-- 1 file changed, 125 insertions(+), 8 deletions(-) diff --git a/lib/librte_eal/linuxapp/eal/eal_vfio.c b/lib/librte_eal/linuxapp/eal/eal_vfio.c index 5084a6b..ae47a5f 100644 --- a/lib/librte_eal/linuxapp/eal/eal_vfio.c +++ b/lib/librte_eal/linuxapp/eal/eal_vfio.c @@ -7,6 +7,7 @@ #include #include +#include #include #include #include @@ -18,6 +19,8 @@ #ifdef VFIO_PRESENT +#define VFIO_MEM_EVENT_CLB_NAME "vfio_mem_event_clb" + /* per-process VFIO config */ static struct vfio_config vfio_cfg; @@ -53,6 +56,42 @@ static const struct vfio_iommu_type iommu_types[] = { }, }; +/* for sPAPR IOMMU, we will need to walk memseg list, but we cannot use + * rte_memseg_walk() because by the time we enter callback we will be holding a + * write lock, so regular rte-memseg_walk will deadlock. copying the same + * iteration code everywhere is not ideal as well. so, use a lockless copy of + * memseg walk here. + */ +static int +memseg_walk_thread_unsafe(rte_memseg_walk_t func, void *arg) +{ + struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config; + int i, ms_idx, ret = 0; + + for (i = 0; i < RTE_MAX_MEMSEG_LISTS; i++) { + struct rte_memseg_list *msl = &mcfg->memsegs[i]; + const struct rte_memseg *ms; + struct rte_fbarray *arr; + + if (msl->memseg_arr.count == 0) + continue; + + arr = &msl->memseg_arr; + + ms_idx = rte_fbarray_find_next_used(arr, 0); + while (ms_idx >= 0) { + ms = rte_fbarray_get(arr, ms_idx); + ret = func(msl, ms, arg); + if (ret < 0) + return -1; + if (ret > 0) + return 1; + ms_idx = rte_fbarray_find_next_used(arr, ms_idx + 1); + } + } + return 0; +} + int vfio_get_group_fd(int iommu_group_no) { @@ -214,6 +253,38 @@ vfio_group_device_count(int vfio_group_fd) return vfio_cfg.vfio_groups[i].devices; } +static void +vfio_mem_event_callback(enum rte_mem_event type, const void *addr, size_t len) +{ + struct rte_memseg_list *msl; + struct rte_memseg *ms; + size_t cur_len = 0; + + msl = rte_mem_virt2memseg_list(addr); + + /* for IOVA as VA mode, no need to care for IOVA addresses */ + if (rte_eal_iova_mode() == RTE_IOVA_VA) { + uint64_t vfio_va = (uint64_t)(uintptr_t)addr; + if (type == RTE_MEM_EVENT_ALLOC) + rte_vfio_dma_map(vfio_va, vfio_va, len); + else + rte_vfio_dma_unmap(vfio_va, vfio_va, len); + return; + } + + /* memsegs are contiguous in memory */ + ms = rte_mem_virt2memseg(addr, msl); + while (cur_len < len) { + if (type == RTE_MEM_EVENT_ALLOC) + rte_vfio_dma_map(ms->addr_64, ms->iova, ms->len); + else + rte_vfio_dma_unmap(ms->addr_64, ms->iova, ms->len); + + cur_len += ms->len; + ++ms; + } +} + int rte_vfio_clear_group(int vfio_group_fd) { @@ -276,6 +347,8 @@ int rte_vfio_setup_device(const char *sysfs_base, const char *dev_addr, int *vfio_dev_fd, struct vfio_device_info *device_info) { + struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config; + rte_rwlock_t *mem_lock = &mcfg->memory_hotplug_lock; struct vfio_group_status group_status = { .argsz = sizeof(group_status) }; @@ -363,6 +436,10 @@ rte_vfio_setup_device(const char *sysfs_base, const char *dev_addr, rte_vfio_clear_group(vfio_group_fd); return -1; } + /* lock memory hotplug before mapping and release it + * after registering callback, to prevent races + */ + rte_rwlock_read_lock(mem_lock); ret = t->dma_map_func(vfio_cfg.vfio_container_fd); if (ret) { RTE_LOG(ERR, EAL, @@ -370,10 +447,26 @@ rte_vfio_setup_device(const char *sysfs_base, const char *dev_addr, dev_addr, errno, strerror(errno)); close(vfio_group_fd); rte_vfio_clear_group(vfio_group_fd); + rte_rwlock_read_unlock(mem_lock); return -1; } vfio_cfg.vfio_iommu_type = t; + + /* register callback for mem events */ + ret = rte_mem_event_callback_register( + VFIO_MEM_EVENT_CLB_NAME, + vfio_mem_event_callback); + /* unlock memory hotplug */ + rte_rwlock_read_unlock(mem_lock); + if (ret && rte_errno == ENOTSUP) { + RTE_LOG(DEBUG, EAL, "Memory event callbacks not supported\n"); + } else if (ret) { + RTE_LOG(ERR, EAL, "Could not install memory event callback for VFIO\n"); + return -1; + } else { + RTE_LOG(DEBUG, EAL, "Installed memory event callback for VFIO\n"); + } } } @@ -411,6 +504,8 @@ int rte_vfio_release_device(const char *sysfs_base, const char *dev_addr, int vfio_dev_fd) { + struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config; + rte_rwlock_t *mem_lock = &mcfg->memory_hotplug_lock; struct vfio_group_status group_status = { .argsz = sizeof(group_status) }; @@ -418,13 +513,20 @@ rte_vfio_release_device(const char *sysfs_base, const char *dev_addr, int iommu_group_no; int ret; + /* we don't want any DMA mapping messages to come while we're detaching + * VFIO device, because this might be the last device and we might need + * to unregister the callback. + */ + rte_rwlock_read_lock(mem_lock); + /* get group number */ ret = vfio_get_group_no(sysfs_base, dev_addr, &iommu_group_no); if (ret <= 0) { RTE_LOG(WARNING, EAL, " %s not managed by VFIO driver\n", dev_addr); /* This is an error at this point. */ - return -1; + ret = -1; + goto out; } /* get the actual group fd */ @@ -432,7 +534,8 @@ rte_vfio_release_device(const char *sysfs_base, const char *dev_addr, if (vfio_group_fd <= 0) { RTE_LOG(INFO, EAL, "vfio_get_group_fd failed for %s\n", dev_addr); - return -1; + ret = -1; + goto out; } /* At this point we got an active group. Closing it will make the @@ -444,7 +547,8 @@ rte_vfio_release_device(const char *sysfs_base, const char *dev_addr, if (close(vfio_dev_fd) < 0) { RTE_LOG(INFO, EAL, "Error when closing vfio_dev_fd for %s\n", dev_addr); - return -1; + ret = -1; + goto out; } /* An VFIO group can have several devices attached. Just when there is @@ -456,17 +560,30 @@ rte_vfio_release_device(const char *sysfs_base, const char *dev_addr, if (close(vfio_group_fd) < 0) { RTE_LOG(INFO, EAL, "Error when closing vfio_group_fd for %s\n", dev_addr); - return -1; + ret = -1; + goto out; } if (rte_vfio_clear_group(vfio_group_fd) < 0) { RTE_LOG(INFO, EAL, "Error when clearing group for %s\n", dev_addr); - return -1; + ret = -1; + goto out; } } - return 0; + /* if there are no active device groups, unregister the callback to + * avoid spurious attempts to map/unmap memory from VFIO. + */ + if (vfio_cfg.vfio_active_groups == 0) + rte_mem_event_callback_unregister(VFIO_MEM_EVENT_CLB_NAME); + + /* success */ + ret = 0; + +out: + rte_rwlock_read_unlock(mem_lock); + return ret; } int @@ -884,7 +1001,7 @@ vfio_spapr_dma_mem_map(int vfio_container_fd, uint64_t vaddr, uint64_t iova, /* check if window size needs to be adjusted */ memset(¶m, 0, sizeof(param)); - if (rte_memseg_walk(vfio_spapr_window_size_walk, ¶m) < 0) { + if (memseg_walk_thread_unsafe(vfio_spapr_window_size_walk, ¶m) < 0) { RTE_LOG(ERR, EAL, "Could not get window size\n"); return -1; } @@ -903,7 +1020,7 @@ vfio_spapr_dma_mem_map(int vfio_container_fd, uint64_t vaddr, uint64_t iova, RTE_LOG(ERR, EAL, "Could not create new DMA window\n"); return -1; } - if (rte_memseg_walk(vfio_spapr_map_walk, + if (memseg_walk_thread_unsafe(vfio_spapr_map_walk, &vfio_container_fd) < 0) { RTE_LOG(ERR, EAL, "Could not recreate DMA maps\n"); return -1; -- 2.7.4