diff options
Diffstat (limited to 'hw/virtio/vhost.c')
| -rw-r--r-- | hw/virtio/vhost.c | 66 |
1 files changed, 56 insertions, 10 deletions
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c index d8d0ef9..250f886 100644 --- a/hw/virtio/vhost.c +++ b/hw/virtio/vhost.c @@ -522,10 +522,28 @@ static void vhost_region_add_section(struct vhost_dev *dev, uint64_t mrs_gpa = section->offset_within_address_space; uintptr_t mrs_host = (uintptr_t)memory_region_get_ram_ptr(section->mr) + section->offset_within_region; + RAMBlock *mrs_rb = section->mr->ram_block; + size_t mrs_page = qemu_ram_pagesize(mrs_rb); trace_vhost_region_add_section(section->mr->name, mrs_gpa, mrs_size, mrs_host); + /* Round the section to it's page size */ + /* First align the start down to a page boundary */ + uint64_t alignage = mrs_host & (mrs_page - 1); + if (alignage) { + mrs_host -= alignage; + mrs_size += alignage; + mrs_gpa -= alignage; + } + /* Now align the size up to a page boundary */ + alignage = mrs_size & (mrs_page - 1); + if (alignage) { + mrs_size += mrs_page - alignage; + } + trace_vhost_region_add_section_aligned(section->mr->name, mrs_gpa, mrs_size, + mrs_host); + if (dev->n_tmp_sections) { /* Since we already have at least one section, lets see if * this extends it; since we're scanning in order, we only @@ -542,18 +560,46 @@ static void vhost_region_add_section(struct vhost_dev *dev, prev_sec->offset_within_region; uint64_t prev_host_end = range_get_last(prev_host_start, prev_size); - if (prev_gpa_end + 1 == mrs_gpa && - prev_host_end + 1 == mrs_host && - section->mr == prev_sec->mr && - (!dev->vhost_ops->vhost_backend_can_merge || - dev->vhost_ops->vhost_backend_can_merge(dev, + if (mrs_gpa <= (prev_gpa_end + 1)) { + /* OK, looks like overlapping/intersecting - it's possible that + * the rounding to page sizes has made them overlap, but they should + * match up in the same RAMBlock if they do. + */ + if (mrs_gpa < prev_gpa_start) { + error_report("%s:Section rounded to %"PRIx64 + " prior to previous %"PRIx64, + __func__, mrs_gpa, prev_gpa_start); + /* A way to cleanly fail here would be better */ + return; + } + /* Offset from the start of the previous GPA to this GPA */ + size_t offset = mrs_gpa - prev_gpa_start; + + if (prev_host_start + offset == mrs_host && + section->mr == prev_sec->mr && + (!dev->vhost_ops->vhost_backend_can_merge || + dev->vhost_ops->vhost_backend_can_merge(dev, mrs_host, mrs_size, prev_host_start, prev_size))) { - /* The two sections abut */ - need_add = false; - prev_sec->size = int128_add(prev_sec->size, section->size); - trace_vhost_region_add_section_abut(section->mr->name, - mrs_size + prev_size); + uint64_t max_end = MAX(prev_host_end, mrs_host + mrs_size); + need_add = false; + prev_sec->offset_within_address_space = + MIN(prev_gpa_start, mrs_gpa); + prev_sec->offset_within_region = + MIN(prev_host_start, mrs_host) - + (uintptr_t)memory_region_get_ram_ptr(prev_sec->mr); + prev_sec->size = int128_make64(max_end - MIN(prev_host_start, + mrs_host)); + trace_vhost_region_add_section_merge(section->mr->name, + int128_get64(prev_sec->size), + prev_sec->offset_within_address_space, + prev_sec->offset_within_region); + } else { + error_report("%s: Overlapping but not coherent sections " + "at %"PRIx64, + __func__, mrs_gpa); + return; + } } } |