diff options
Diffstat (limited to 'contrib/libvhost-user/libvhost-user.c')
| -rw-r--r-- | contrib/libvhost-user/libvhost-user.c | 133 |
1 files changed, 120 insertions, 13 deletions
diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c index 54dbc933b3..2e358b5bce 100644 --- a/contrib/libvhost-user/libvhost-user.c +++ b/contrib/libvhost-user/libvhost-user.c @@ -118,15 +118,22 @@ vu_panic(VuDev *dev, const char *msg, ...) /* Translate guest physical address to our virtual address. */ void * -vu_gpa_to_va(VuDev *dev, uint64_t guest_addr) +vu_gpa_to_va(VuDev *dev, uint64_t *plen, uint64_t guest_addr) { int i; + if (*plen == 0) { + return NULL; + } + /* Find matching memory region. */ for (i = 0; i < dev->nregions; i++) { VuDevRegion *r = &dev->regions[i]; if ((guest_addr >= r->gpa) && (guest_addr < (r->gpa + r->size))) { + if ((guest_addr + *plen) > (r->gpa + r->size)) { + *plen = r->gpa + r->size - guest_addr; + } return (void *)(uintptr_t) guest_addr - r->gpa + r->mmap_addr + r->mmap_offset; } @@ -1116,6 +1123,37 @@ virtqueue_get_head(VuDev *dev, VuVirtq *vq, return true; } +static int +virtqueue_read_indirect_desc(VuDev *dev, struct vring_desc *desc, + uint64_t addr, size_t len) +{ + struct vring_desc *ori_desc; + uint64_t read_len; + + if (len > (VIRTQUEUE_MAX_SIZE * sizeof(struct vring_desc))) { + return -1; + } + + if (len == 0) { + return -1; + } + + while (len) { + read_len = len; + ori_desc = vu_gpa_to_va(dev, &read_len, addr); + if (!ori_desc) { + return -1; + } + + memcpy(desc, ori_desc, read_len); + len -= read_len; + addr += read_len; + desc += read_len; + } + + return 0; +} + enum { VIRTQUEUE_READ_DESC_ERROR = -1, VIRTQUEUE_READ_DESC_DONE = 0, /* end of chain */ @@ -1162,8 +1200,10 @@ vu_queue_get_avail_bytes(VuDev *dev, VuVirtq *vq, unsigned int *in_bytes, } while ((rc = virtqueue_num_heads(dev, vq, idx)) > 0) { - unsigned int max, num_bufs, indirect = 0; + unsigned int max, desc_len, num_bufs, indirect = 0; + uint64_t desc_addr, read_len; struct vring_desc *desc; + struct vring_desc desc_buf[VIRTQUEUE_MAX_SIZE]; unsigned int i; max = vq->vring.num; @@ -1187,8 +1227,24 @@ vu_queue_get_avail_bytes(VuDev *dev, VuVirtq *vq, unsigned int *in_bytes, /* loop over the indirect descriptor table */ indirect = 1; - max = desc[i].len / sizeof(struct vring_desc); - desc = vu_gpa_to_va(dev, desc[i].addr); + desc_addr = desc[i].addr; + desc_len = desc[i].len; + max = desc_len / sizeof(struct vring_desc); + read_len = desc_len; + desc = vu_gpa_to_va(dev, &read_len, desc_addr); + if (unlikely(desc && read_len != desc_len)) { + /* Failed to use zero copy */ + desc = NULL; + if (!virtqueue_read_indirect_desc(dev, desc_buf, + desc_addr, + desc_len)) { + desc = desc_buf; + } + } + if (!desc) { + vu_panic(dev, "Invalid indirect buffer table"); + goto err; + } num_bufs = i = 0; } @@ -1386,9 +1442,24 @@ virtqueue_map_desc(VuDev *dev, return; } - iov[num_sg].iov_base = vu_gpa_to_va(dev, pa); - iov[num_sg].iov_len = sz; - num_sg++; + while (sz) { + uint64_t len = sz; + + if (num_sg == max_num_sg) { + vu_panic(dev, "virtio: too many descriptors in indirect table"); + return; + } + + iov[num_sg].iov_base = vu_gpa_to_va(dev, &len, pa); + if (iov[num_sg].iov_base == NULL) { + vu_panic(dev, "virtio: invalid address for buffers"); + return; + } + iov[num_sg].iov_len = len; + num_sg++; + sz -= len; + pa += len; + } *p_num_sg = num_sg; } @@ -1420,10 +1491,12 @@ virtqueue_alloc_element(size_t sz, void * vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz) { - unsigned int i, head, max; + unsigned int i, head, max, desc_len; + uint64_t desc_addr, read_len; VuVirtqElement *elem; unsigned out_num, in_num; struct iovec iov[VIRTQUEUE_MAX_SIZE]; + struct vring_desc desc_buf[VIRTQUEUE_MAX_SIZE]; struct vring_desc *desc; int rc; @@ -1464,8 +1537,24 @@ vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz) } /* loop over the indirect descriptor table */ - max = desc[i].len / sizeof(struct vring_desc); - desc = vu_gpa_to_va(dev, desc[i].addr); + desc_addr = desc[i].addr; + desc_len = desc[i].len; + max = desc_len / sizeof(struct vring_desc); + read_len = desc_len; + desc = vu_gpa_to_va(dev, &read_len, desc_addr); + if (unlikely(desc && read_len != desc_len)) { + /* Failed to use zero copy */ + desc = NULL; + if (!virtqueue_read_indirect_desc(dev, desc_buf, + desc_addr, + desc_len)) { + desc = desc_buf; + } + } + if (!desc) { + vu_panic(dev, "Invalid indirect buffer table"); + return NULL; + } i = 0; } @@ -1541,7 +1630,9 @@ vu_log_queue_fill(VuDev *dev, VuVirtq *vq, unsigned int len) { struct vring_desc *desc = vq->vring.desc; - unsigned int i, max, min; + unsigned int i, max, min, desc_len; + uint64_t desc_addr, read_len; + struct vring_desc desc_buf[VIRTQUEUE_MAX_SIZE]; unsigned num_bufs = 0; max = vq->vring.num; @@ -1553,8 +1644,24 @@ vu_log_queue_fill(VuDev *dev, VuVirtq *vq, } /* loop over the indirect descriptor table */ - max = desc[i].len / sizeof(struct vring_desc); - desc = vu_gpa_to_va(dev, desc[i].addr); + desc_addr = desc[i].addr; + desc_len = desc[i].len; + max = desc_len / sizeof(struct vring_desc); + read_len = desc_len; + desc = vu_gpa_to_va(dev, &read_len, desc_addr); + if (unlikely(desc && read_len != desc_len)) { + /* Failed to use zero copy */ + desc = NULL; + if (!virtqueue_read_indirect_desc(dev, desc_buf, + desc_addr, + desc_len)) { + desc = desc_buf; + } + } + if (!desc) { + vu_panic(dev, "Invalid indirect buffer table"); + return; + } i = 0; } |