diff options
-rw-r--r-- | include/libvfio-user.h | 2 | ||||
-rw-r--r-- | lib/common.h | 1 | ||||
-rw-r--r-- | lib/dma.c | 11 | ||||
-rw-r--r-- | lib/dma.h | 3 | ||||
-rw-r--r-- | lib/libvfio-user.c | 7 | ||||
-rw-r--r-- | lib/private.h | 10 | ||||
-rw-r--r-- | test/py/libvfio_user.py | 4 | ||||
-rw-r--r-- | test/py/test_dma_map.py | 101 |
8 files changed, 129 insertions, 10 deletions
diff --git a/include/libvfio-user.h b/include/libvfio-user.h index 009ba83..c9e8ca2 100644 --- a/include/libvfio-user.h +++ b/include/libvfio-user.h @@ -58,8 +58,6 @@ extern "C" { #define LIB_VFIO_USER_MAJOR 0 #define LIB_VFIO_USER_MINOR 1 -#define VFU_DMA_REGIONS 0x10 - /* DMA addresses cannot be directly de-referenced. */ typedef void *vfu_dma_addr_t; diff --git a/lib/common.h b/lib/common.h index a56a0f0..599759f 100644 --- a/lib/common.h +++ b/lib/common.h @@ -43,6 +43,7 @@ #define UNUSED __attribute__((unused)) #define EXPORT __attribute__((visibility("default"))) +#define ONE_TB (1024UL * 1024 * 1024 * 1024) #define PAGE_SIZE (size_t)sysconf(_SC_PAGE_SIZE) #define PAGE_ALIGNED(x) (((x) & ((typeof(x))(PAGE_SIZE) - 1)) == 0) @@ -71,7 +71,7 @@ fds_are_same_file(int fd1, int fd2) } dma_controller_t * -dma_controller_create(vfu_ctx_t *vfu_ctx, int max_regions) +dma_controller_create(vfu_ctx_t *vfu_ctx, size_t max_regions, size_t max_size) { dma_controller_t *dma; @@ -83,7 +83,8 @@ dma_controller_create(vfu_ctx_t *vfu_ctx, int max_regions) } dma->vfu_ctx = vfu_ctx; - dma->max_regions = max_regions; + dma->max_regions = (int)max_regions; + dma->max_size = max_size; dma->nregions = 0; memset(dma->regions, 0, max_regions * sizeof(dma->regions[0])); dma->dirty_pgsize = 0; @@ -298,6 +299,12 @@ MOCK_DEFINE(dma_controller_add_region)(dma_controller_t *dma, snprintf(rstr, sizeof(rstr), "[%p, %p) fd=%d offset=%#lx prot=%#x", dma_addr, (char *)dma_addr + size, fd, offset, prot); + if (size > dma->max_size) { + vfu_log(dma->vfu_ctx, LOG_ERR, "DMA region size %zu > max %zu", + size, dma->max_size); + return ERROR_INT(ENOSPC); + } + for (idx = 0; idx < dma->nregions; idx++) { region = &dma->regions[idx]; @@ -92,6 +92,7 @@ typedef struct { typedef struct dma_controller { int max_regions; + size_t max_size; int nregions; struct vfu_ctx *vfu_ctx; size_t dirty_pgsize; // Dirty page granularity @@ -99,7 +100,7 @@ typedef struct dma_controller { } dma_controller_t; dma_controller_t * -dma_controller_create(vfu_ctx_t *vfu_ctx, int max_regions); +dma_controller_create(vfu_ctx_t *vfu_ctx, size_t max_regions, size_t max_size); void dma_controller_remove_all_regions(dma_controller_t *dma, diff --git a/lib/libvfio-user.c b/lib/libvfio-user.c index c569714..452b15f 100644 --- a/lib/libvfio-user.c +++ b/lib/libvfio-user.c @@ -671,9 +671,7 @@ handle_dirty_pages_get(vfu_ctx_t *vfu_ctx, vfu_msg_t *msg) return -1; } - /* - * FIXME: this is unbounded until we can limit the maximum DMA region size. - */ + /* NB: this is bound by MAX_DMA_SIZE. */ argsz = sizeof(*dirty_pages_out) + sizeof(*range_out) + range_in->bitmap.size; @@ -1506,7 +1504,8 @@ vfu_setup_device_dma(vfu_ctx_t *vfu_ctx, vfu_dma_register_cb_t *dma_register, assert(vfu_ctx != NULL); // Create the internal DMA controller. - vfu_ctx->dma = dma_controller_create(vfu_ctx, VFU_DMA_REGIONS); + vfu_ctx->dma = dma_controller_create(vfu_ctx, MAX_DMA_REGIONS, + MAX_DMA_SIZE); if (vfu_ctx->dma == NULL) { return ERROR_INT(errno); } diff --git a/lib/private.h b/lib/private.h index c9a8af7..c7c0627 100644 --- a/lib/private.h +++ b/lib/private.h @@ -35,8 +35,16 @@ #include <errno.h> -#include "pci_caps.h" #include "common.h" +#include "pci_caps.h" + +/* + * The main reason we limit the size of an individual DMA region from the client + * is to limit the size of the dirty bitmaps: this corresponds to 256MB at a 4K + * page size. + */ +#define MAX_DMA_SIZE (8 * ONE_TB) +#define MAX_DMA_REGIONS 16 #define SERVER_MAX_MSG_SIZE 65536 diff --git a/test/py/libvfio_user.py b/test/py/libvfio_user.py index a664da0..b1ebd4b 100644 --- a/test/py/libvfio_user.py +++ b/test/py/libvfio_user.py @@ -108,6 +108,10 @@ SERVER_MAX_FDS = 8 SERVER_MAX_MSG_SIZE = 65536 +MAX_DMA_REGIONS = 16 +ONE_TB = (1024 * 1024 * 1024 * 1024) +MAX_DMA_SIZE = (8 * ONE_TB) + # enum vfio_user_command VFIO_USER_VERSION = 1 VFIO_USER_DMA_MAP = 2 diff --git a/test/py/test_dma_map.py b/test/py/test_dma_map.py new file mode 100644 index 0000000..3358abc --- /dev/null +++ b/test/py/test_dma_map.py @@ -0,0 +1,101 @@ +# +# Copyright (c) 2021 Nutanix Inc. All rights reserved. +# +# Authors: John Levon <john.levon@nutanix.com> +# +# 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. +# * Neither the name of Nutanix nor the names of its contributors may be +# used to endorse or promote products derived from this software without +# specific prior written permission. +# +# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" +# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +# ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY +# DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES +# (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR +# SERVICESLOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER +# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH +# DAMAGE. +# + +from libvfio_user import * +import errno + +# +# NB: this is currently very incomplete +# + +ctx = None + +@vfu_dma_register_cb_t +def dma_register(ctx, info): + pass + +@vfu_dma_unregister_cb_t +def dma_unregister(ctx, info): + pass + return 0 + +def test_dma_map_setup(): + global ctx + + ctx = vfu_create_ctx(flags=LIBVFIO_USER_FLAG_ATTACH_NB) + assert ctx != None + + ret = vfu_pci_init(ctx) + assert ret == 0 + + ret = vfu_setup_device_dma(ctx, dma_register, dma_unregister) + assert ret == 0 + + ret = vfu_realize_ctx(ctx) + assert ret == 0 + +def test_dma_region_too_big(): + sock = connect_client(ctx) + + payload = vfio_user_dma_map(argsz=len(vfio_user_dma_map()), + flags=(VFIO_USER_F_DMA_REGION_READ | + VFIO_USER_F_DMA_REGION_WRITE), + offset=0, addr=0x10000, size=MAX_DMA_SIZE + 4096) + + hdr = vfio_user_header(VFIO_USER_DMA_MAP, size=len(payload)) + + sock.send(hdr + payload) + vfu_run_ctx(ctx) + get_reply(sock, expect=errno.ENOSPC) + + disconnect_client(ctx, sock) + +def test_dma_region_too_many(): + sock = connect_client(ctx) + + for i in range(1, MAX_DMA_REGIONS + 2): + payload = vfio_user_dma_map(argsz=len(vfio_user_dma_map()), + flags=(VFIO_USER_F_DMA_REGION_READ | + VFIO_USER_F_DMA_REGION_WRITE), + offset=0, addr=0x1000 * i, size=4096) + + hdr = vfio_user_header(VFIO_USER_DMA_MAP, size=len(payload)) + + sock.send(hdr + payload) + vfu_run_ctx(ctx) + + if i == MAX_DMA_REGIONS + 1: + get_reply(sock, expect=errno.EINVAL) + else: + get_reply(sock) + + disconnect_client(ctx, sock) + +def test_dirty_pages_cleanup(): + vfu_destroy_ctx(ctx) |