From ec09c280b83975b6444cb87eaf12fee970fde70f Mon Sep 17 00:00:00 2001 From: Jianfeng Tan Date: Thu, 12 Nov 2015 14:06:01 +0800 Subject: [PATCH] vhost: fix mmap not aligned with hugepage size This patch fixes a bug under lower version linux kernel, mmap() fails when length is not aligned with hugepage size. mmap() without flag of MAP_ANONYMOUS, should be called with length argument aligned with hugepagesz at older longterm version Linux, like 2.6.32 and 3.2.72, or mmap() will fail with EINVAL. This bug was fixed in Linux kernel by commit: dab2d3dc45ae7343216635d981d43637e1cb7d45 To avoid failure, make sure in caller to keep length aligned. Signed-off-by: Jianfeng Tan Acked-by: Huawei Xie --- lib/librte_vhost/vhost_user/virtio-net-user.c | 36 +++++++++++-------- 1 file changed, 21 insertions(+), 15 deletions(-) diff --git a/lib/librte_vhost/vhost_user/virtio-net-user.c b/lib/librte_vhost/vhost_user/virtio-net-user.c index d07452a6f8..99da029dd5 100644 --- a/lib/librte_vhost/vhost_user/virtio-net-user.c +++ b/lib/librte_vhost/vhost_user/virtio-net-user.c @@ -74,7 +74,6 @@ free_mem_region(struct virtio_net *dev) { struct orig_region_map *region; unsigned int idx; - uint64_t alignment; if (!dev || !dev->mem) return; @@ -82,12 +81,8 @@ free_mem_region(struct virtio_net *dev) region = orig_region(dev->mem, dev->mem->nregions); for (idx = 0; idx < dev->mem->nregions; idx++) { if (region[idx].mapped_address) { - alignment = region[idx].blksz; - munmap((void *)(uintptr_t) - RTE_ALIGN_FLOOR( - region[idx].mapped_address, alignment), - RTE_ALIGN_CEIL( - region[idx].mapped_size, alignment)); + munmap((void *)(uintptr_t)region[idx].mapped_address, + region[idx].mapped_size); close(region[idx].fd); } } @@ -147,6 +142,18 @@ user_set_mem_table(struct vhost_device_ctx ctx, struct VhostUserMsg *pmsg) /* This is ugly */ mapped_size = memory.regions[idx].memory_size + memory.regions[idx].mmap_offset; + + /* mmap() without flag of MAP_ANONYMOUS, should be called + * with length argument aligned with hugepagesz at older + * longterm version Linux, like 2.6.32 and 3.2.72, or + * mmap() will fail with EINVAL. + * + * to avoid failure, make sure in caller to keep length + * aligned. + */ + alignment = get_blk_size(pmsg->fds[idx]); + mapped_size = RTE_ALIGN_CEIL(mapped_size, alignment); + mapped_address = (uint64_t)(uintptr_t)mmap(NULL, mapped_size, PROT_READ | PROT_WRITE, MAP_SHARED, @@ -154,9 +161,11 @@ user_set_mem_table(struct vhost_device_ctx ctx, struct VhostUserMsg *pmsg) 0); RTE_LOG(INFO, VHOST_CONFIG, - "mapped region %d fd:%d to %p sz:0x%"PRIx64" off:0x%"PRIx64"\n", + "mapped region %d fd:%d to:%p sz:0x%"PRIx64" " + "off:0x%"PRIx64" align:0x%"PRIx64"\n", idx, pmsg->fds[idx], (void *)(uintptr_t)mapped_address, - mapped_size, memory.regions[idx].mmap_offset); + mapped_size, memory.regions[idx].mmap_offset, + alignment); if (mapped_address == (uint64_t)(uintptr_t)MAP_FAILED) { RTE_LOG(ERR, VHOST_CONFIG, @@ -166,7 +175,7 @@ user_set_mem_table(struct vhost_device_ctx ctx, struct VhostUserMsg *pmsg) pregion_orig[idx].mapped_address = mapped_address; pregion_orig[idx].mapped_size = mapped_size; - pregion_orig[idx].blksz = get_blk_size(pmsg->fds[idx]); + pregion_orig[idx].blksz = alignment; pregion_orig[idx].fd = pmsg->fds[idx]; mapped_address += memory.regions[idx].mmap_offset; @@ -193,11 +202,8 @@ user_set_mem_table(struct vhost_device_ctx ctx, struct VhostUserMsg *pmsg) err_mmap: while (idx--) { - alignment = pregion_orig[idx].blksz; - munmap((void *)(uintptr_t)RTE_ALIGN_FLOOR( - pregion_orig[idx].mapped_address, alignment), - RTE_ALIGN_CEIL(pregion_orig[idx].mapped_size, - alignment)); + munmap((void *)(uintptr_t)pregion_orig[idx].mapped_address, + pregion_orig[idx].mapped_size); close(pregion_orig[idx].fd); } free(dev->mem); -- 2.20.1