Add ability to do async operations during memory transactions Signed-off-by: Jagannathan Raman <jag.ra...@oracle.com> Signed-off-by: Elena Ufimtseva <elena.ufimts...@oracle.com> Signed-off-by: John G Johnson <john.g.john...@oracle.com> --- hw/vfio/user-protocol.h | 32 +++++++ include/hw/vfio/vfio-common.h | 9 +- hw/vfio/common.c | 63 +++++++++--- hw/vfio/user.c | 217 ++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 305 insertions(+), 16 deletions(-)
diff --git a/hw/vfio/user-protocol.h b/hw/vfio/user-protocol.h index 4852882..ad63f21 100644 --- a/hw/vfio/user-protocol.h +++ b/hw/vfio/user-protocol.h @@ -94,6 +94,31 @@ typedef struct { /* + * VFIO_USER_DMA_MAP + * imported from struct vfio_iommu_type1_dma_map + */ +typedef struct { + VFIOUserHdr hdr; + uint32_t argsz; + uint32_t flags; + uint64_t offset; /* FD offset */ + uint64_t iova; + uint64_t size; +} VFIOUserDMAMap; + +/* + * VFIO_USER_DMA_UNMAP + * imported from struct vfio_iommu_type1_dma_unmap + */ +typedef struct { + VFIOUserHdr hdr; + uint32_t argsz; + uint32_t flags; + uint64_t iova; + uint64_t size; +} VFIOUserDMAUnmap; + +/* * VFIO_USER_DEVICE_GET_INFO * imported from struct_device_info */ @@ -157,4 +182,11 @@ typedef struct { char data[]; } VFIOUserRegionRW; +/*imported from struct vfio_bitmap */ +typedef struct { + uint64_t pgsize; + uint64_t size; + char data[]; +} VFIOUserBitmap; + #endif /* VFIO_USER_PROTOCOL_H */ diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h index 59a8299..a84e10a 100644 --- a/include/hw/vfio/vfio-common.h +++ b/include/hw/vfio/vfio-common.h @@ -90,6 +90,7 @@ typedef struct VFIOContainer { VFIOContIO *io_ops; bool initialized; bool dirty_pages_supported; + bool async_ops; uint64_t dirty_pgsizes; uint64_t max_dirty_bitmap_size; unsigned long pgsizes; @@ -199,7 +200,7 @@ struct VFIODevIO { ((vdev)->io_ops->region_write((vdev), (nr), (off), (size), (data), (post))) struct VFIOContIO { - int (*dma_map)(VFIOContainer *container, + int (*dma_map)(VFIOContainer *container, MemoryRegion *mr, struct vfio_iommu_type1_dma_map *map); int (*dma_unmap)(VFIOContainer *container, struct vfio_iommu_type1_dma_unmap *unmap, @@ -207,14 +208,16 @@ struct VFIOContIO { int (*dirty_bitmap)(VFIOContainer *container, struct vfio_iommu_type1_dirty_bitmap *bitmap, struct vfio_iommu_type1_dirty_bitmap_get *range); + void (*wait_commit)(VFIOContainer *container); }; -#define CONT_DMA_MAP(cont, map) \ - ((cont)->io_ops->dma_map((cont), (map))) +#define CONT_DMA_MAP(cont, mr, map) \ + ((cont)->io_ops->dma_map((cont), (mr), (map))) #define CONT_DMA_UNMAP(cont, unmap, bitmap) \ ((cont)->io_ops->dma_unmap((cont), (unmap), (bitmap))) #define CONT_DIRTY_BITMAP(cont, bitmap, range) \ ((cont)->io_ops->dirty_bitmap((cont), (bitmap), (range))) +#define CONT_WAIT_COMMIT(cont) ((cont)->io_ops->wait_commit(cont)) extern VFIODevIO vfio_dev_io_ioctl; extern VFIOContIO vfio_cont_io_ioctl; diff --git a/hw/vfio/common.c b/hw/vfio/common.c index 9a67934..ca51baa 100644 --- a/hw/vfio/common.c +++ b/hw/vfio/common.c @@ -480,7 +480,7 @@ static int vfio_dma_unmap(VFIOContainer *container, return CONT_DMA_UNMAP(container, &unmap, NULL); } -static int vfio_dma_map(VFIOContainer *container, hwaddr iova, +static int vfio_dma_map(VFIOContainer *container, MemoryRegion *mr, hwaddr iova, ram_addr_t size, void *vaddr, bool readonly) { struct vfio_iommu_type1_dma_map map = { @@ -496,7 +496,7 @@ static int vfio_dma_map(VFIOContainer *container, hwaddr iova, map.flags |= VFIO_DMA_MAP_FLAG_WRITE; } - ret = CONT_DMA_MAP(container, &map); + ret = CONT_DMA_MAP(container, mr, &map); if (ret < 0) { error_report("VFIO_MAP_DMA failed: %s", strerror(-ret)); @@ -559,7 +559,8 @@ static bool vfio_listener_skipped_section(MemoryRegionSection *section) /* Called with rcu_read_lock held. */ static bool vfio_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr, - ram_addr_t *ram_addr, bool *read_only) + ram_addr_t *ram_addr, bool *read_only, + MemoryRegion **mrp) { MemoryRegion *mr; hwaddr xlat; @@ -640,6 +641,10 @@ static bool vfio_get_xlat_addr(IOMMUTLBEntry *iotlb, void **vaddr, *read_only = !writable || mr->readonly; } + if (mrp != NULL) { + *mrp = mr; + } + return true; } @@ -647,6 +652,7 @@ static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb) { VFIOGuestIOMMU *giommu = container_of(n, VFIOGuestIOMMU, n); VFIOContainer *container = giommu->container; + MemoryRegion *mr; hwaddr iova = iotlb->iova + giommu->iommu_offset; void *vaddr; int ret; @@ -665,7 +671,7 @@ static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb) if ((iotlb->perm & IOMMU_RW) != IOMMU_NONE) { bool read_only; - if (!vfio_get_xlat_addr(iotlb, &vaddr, NULL, &read_only)) { + if (!vfio_get_xlat_addr(iotlb, &vaddr, NULL, &read_only, &mr)) { goto out; } /* @@ -675,14 +681,14 @@ static void vfio_iommu_map_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb) * of vaddr will always be there, even if the memory object is * destroyed and its backing memory munmap-ed. */ - ret = vfio_dma_map(container, iova, + ret = vfio_dma_map(container, mr, iova, iotlb->addr_mask + 1, vaddr, read_only); if (ret) { error_report("vfio_dma_map(%p, 0x%"HWADDR_PRIx", " - "0x%"HWADDR_PRIx", %p) = %d (%m)", + "0x%"HWADDR_PRIx", %p)", container, iova, - iotlb->addr_mask + 1, vaddr, ret); + iotlb->addr_mask + 1, vaddr); } } else { ret = vfio_dma_unmap(container, iova, iotlb->addr_mask + 1, iotlb); @@ -737,7 +743,7 @@ static int vfio_ram_discard_notify_populate(RamDiscardListener *rdl, section->offset_within_address_space; vaddr = memory_region_get_ram_ptr(section->mr) + start; - ret = vfio_dma_map(vrdl->container, iova, next - start, + ret = vfio_dma_map(vrdl->container, section->mr, iova, next - start, vaddr, section->readonly); if (ret) { /* Rollback */ @@ -845,6 +851,29 @@ static void vfio_unregister_ram_discard_listener(VFIOContainer *container, g_free(vrdl); } +static void vfio_listener_begin(MemoryListener *listener) +{ + VFIOContainer *container = container_of(listener, VFIOContainer, listener); + + /* + * When DMA space is the physical address space, + * the region add/del listeners will fire during + * memory update transactions. These depend on BQL + * being held, so do any resulting map/demap ops async + * while keeping BQL. + */ + container->async_ops = true; +} + +static void vfio_listener_commit(MemoryListener *listener) +{ + VFIOContainer *container = container_of(listener, VFIOContainer, listener); + + /* wait here for any async requests sent during the transaction */ + CONT_WAIT_COMMIT(container); + container->async_ops = false; +} + static void vfio_listener_region_add(MemoryListener *listener, MemoryRegionSection *section) { @@ -1044,12 +1073,12 @@ static void vfio_listener_region_add(MemoryListener *listener, } } - ret = vfio_dma_map(container, iova, int128_get64(llsize), + ret = vfio_dma_map(container, section->mr, iova, int128_get64(llsize), vaddr, section->readonly); if (ret) { error_setg(&err, "vfio_dma_map(%p, 0x%"HWADDR_PRIx", " - "0x%"HWADDR_PRIx", %p) = %d (%m)", - container, iova, int128_get64(llsize), vaddr, ret); + "0x%"HWADDR_PRIx", %p)", + container, iova, int128_get64(llsize), vaddr); if (memory_region_is_ram_device(section->mr)) { /* Allow unexpected mappings not to be fatal for RAM devices */ error_report_err(err); @@ -1310,7 +1339,7 @@ static void vfio_iommu_map_dirty_notify(IOMMUNotifier *n, IOMMUTLBEntry *iotlb) } rcu_read_lock(); - if (vfio_get_xlat_addr(iotlb, NULL, &translated_addr, NULL)) { + if (vfio_get_xlat_addr(iotlb, NULL, &translated_addr, NULL, NULL)) { int ret; ret = vfio_get_dirty_bitmap(container, iova, iotlb->addr_mask + 1, @@ -1428,6 +1457,8 @@ static void vfio_listener_log_sync(MemoryListener *listener, static const MemoryListener vfio_memory_listener = { .name = "vfio", + .begin = vfio_listener_begin, + .commit = vfio_listener_commit, .region_add = vfio_listener_region_add, .region_del = vfio_listener_region_del, .log_global_start = vfio_listener_log_global_start, @@ -2819,7 +2850,7 @@ VFIODevIO vfio_dev_io_ioctl = { .region_write = vfio_io_region_write, }; -static int vfio_io_dma_map(VFIOContainer *container, +static int vfio_io_dma_map(VFIOContainer *container, MemoryRegion *mr, struct vfio_iommu_type1_dma_map *map) { @@ -2879,8 +2910,14 @@ static int vfio_io_dirty_bitmap(VFIOContainer *container, return ret < 0 ? -errno : ret; } +static void vfio_io_wait_commit(VFIOContainer *container) +{ + /* ioctl()s are synchronous */ +} + VFIOContIO vfio_cont_io_ioctl = { .dma_map = vfio_io_dma_map, .dma_unmap = vfio_io_dma_unmap, .dirty_bitmap = vfio_io_dirty_bitmap, + .wait_commit = vfio_io_wait_commit, }; diff --git a/hw/vfio/user.c b/hw/vfio/user.c index 9e71cdb..5c27a5e 100644 --- a/hw/vfio/user.c +++ b/hw/vfio/user.c @@ -52,8 +52,11 @@ static void vfio_user_request(void *opaque); static int vfio_user_send_queued(VFIOProxy *proxy, VFIOUserMsg *msg); static void vfio_user_send_async(VFIOProxy *proxy, VFIOUserHdr *hdr, VFIOUserFDs *fds); +static void vfio_user_send_nowait(VFIOProxy *proxy, VFIOUserHdr *hdr, + VFIOUserFDs *fds, int rsize); static void vfio_user_send_wait(VFIOProxy *proxy, VFIOUserHdr *hdr, VFIOUserFDs *fds, int rsize, bool nobql); +static void vfio_user_wait_reqs(VFIOProxy *proxy); static void vfio_user_request_msg(VFIOUserHdr *hdr, uint16_t cmd, uint32_t size, uint32_t flags); @@ -563,6 +566,36 @@ static void vfio_user_send_async(VFIOProxy *proxy, VFIOUserHdr *hdr, } } +/* + * nowait send - vfio_wait_reqs() can wait for it later + */ +static void vfio_user_send_nowait(VFIOProxy *proxy, VFIOUserHdr *hdr, + VFIOUserFDs *fds, int rsize) +{ + VFIOUserMsg *msg; + int ret; + + if (hdr->flags & VFIO_USER_NO_REPLY) { + error_printf("vfio_user_send_nowait on async message\n"); + return; + } + + QEMU_LOCK_GUARD(&proxy->lock); + + msg = vfio_user_getmsg(proxy, hdr, fds); + msg->id = hdr->id; + msg->rsize = rsize ? rsize : hdr->size; + msg->type = VFIO_MSG_NOWAIT; + + ret = vfio_user_send_queued(proxy, msg); + if (ret < 0) { + vfio_user_recycle(proxy, msg); + return; + } + + proxy->last_nowait = msg; +} + static void vfio_user_send_wait(VFIOProxy *proxy, VFIOUserHdr *hdr, VFIOUserFDs *fds, int rsize, bool nobql) { @@ -612,6 +645,57 @@ static void vfio_user_send_wait(VFIOProxy *proxy, VFIOUserHdr *hdr, } } +static void vfio_user_wait_reqs(VFIOProxy *proxy) +{ + VFIOUserMsg *msg; + bool iolock = false; + + /* + * Any DMA map/unmap requests sent in the middle + * of a memory region transaction were sent nowait. + * Wait for them here. + */ + qemu_mutex_lock(&proxy->lock); + if (proxy->last_nowait != NULL) { + iolock = qemu_mutex_iothread_locked(); + if (iolock) { + qemu_mutex_unlock_iothread(); + } + + /* + * Change type to WAIT to wait for reply + */ + msg = proxy->last_nowait; + msg->type = VFIO_MSG_WAIT; + while (!msg->complete) { + if (!qemu_cond_timedwait(&msg->cv, &proxy->lock, wait_time)) { + QTAILQ_REMOVE(&proxy->pending, msg, next); + error_printf("vfio_wait_reqs - timed out\n"); + break; + } + } + + if (msg->hdr->flags & VFIO_USER_ERROR) { + error_printf("vfio_user_wait_reqs - error reply on async request "); + error_printf("command %x error %s\n", msg->hdr->command, + strerror(msg->hdr->error_reply)); + } + + proxy->last_nowait = NULL; + /* + * Change type back to NOWAIT to free + */ + msg->type = VFIO_MSG_NOWAIT; + vfio_user_recycle(proxy, msg); + } + + /* lock order is BQL->proxy - don't hold proxy when getting BQL */ + qemu_mutex_unlock(&proxy->lock); + if (iolock) { + qemu_mutex_lock_iothread(); + } +} + static QLIST_HEAD(, VFIOProxy) vfio_user_sockets = QLIST_HEAD_INITIALIZER(vfio_user_sockets); @@ -937,6 +1021,103 @@ int vfio_user_validate_version(VFIODevice *vbasedev, Error **errp) return 0; } +static int vfio_user_dma_map(VFIOProxy *proxy, + struct vfio_iommu_type1_dma_map *map, + int fd, bool will_commit) +{ + VFIOUserFDs *fds = NULL; + VFIOUserDMAMap *msgp = g_malloc0(sizeof(*msgp)); + int ret; + + vfio_user_request_msg(&msgp->hdr, VFIO_USER_DMA_MAP, sizeof(*msgp), 0); + msgp->argsz = map->argsz; + msgp->flags = map->flags; + msgp->offset = map->vaddr; + msgp->iova = map->iova; + msgp->size = map->size; + + /* + * The will_commit case sends without blocking or dropping BQL. + * They're later waited for in vfio_send_wait_reqs. + */ + if (will_commit) { + /* can't use auto variable since we don't block */ + if (fd != -1) { + fds = vfio_user_getfds(1); + fds->send_fds = 1; + fds->fds[0] = fd; + } + vfio_user_send_nowait(proxy, &msgp->hdr, fds, 0); + ret = 0; + } else { + VFIOUserFDs local_fds = { 1, 0, &fd }; + + fds = fd != -1 ? &local_fds : NULL; + vfio_user_send_wait(proxy, &msgp->hdr, fds, 0, will_commit); + ret = (msgp->hdr.flags & VFIO_USER_ERROR) ? -msgp->hdr.error_reply : 0; + g_free(msgp); + } + + return ret; +} + +static int vfio_user_dma_unmap(VFIOProxy *proxy, + struct vfio_iommu_type1_dma_unmap *unmap, + struct vfio_bitmap *bitmap, bool will_commit) +{ + struct { + VFIOUserDMAUnmap msg; + VFIOUserBitmap bitmap; + } *msgp = NULL; + int msize, rsize; + bool blocking = !will_commit; + + if (bitmap == NULL && + (unmap->flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP)) { + error_printf("vfio_user_dma_unmap mismatched flags and bitmap\n"); + return -EINVAL; + } + + /* + * If a dirty bitmap is returned, allocate extra space for it + * and block for reply even in the will_commit case. + * Otherwise, can send the unmap request without waiting. + */ + if (bitmap != NULL) { + blocking = true; + msize = sizeof(*msgp); + rsize = msize + bitmap->size; + msgp = g_malloc0(rsize); + msgp->bitmap.pgsize = bitmap->pgsize; + msgp->bitmap.size = bitmap->size; + } else { + msize = rsize = sizeof(VFIOUserDMAUnmap); + msgp = g_malloc0(rsize); + } + + vfio_user_request_msg(&msgp->msg.hdr, VFIO_USER_DMA_UNMAP, msize, 0); + msgp->msg.argsz = rsize - sizeof(VFIOUserHdr); + msgp->msg.argsz = unmap->argsz; + msgp->msg.flags = unmap->flags; + msgp->msg.iova = unmap->iova; + msgp->msg.size = unmap->size; + + if (blocking) { + vfio_user_send_wait(proxy, &msgp->msg.hdr, NULL, rsize, will_commit); + if (msgp->msg.hdr.flags & VFIO_USER_ERROR) { + return -msgp->msg.hdr.error_reply; + } + if (bitmap != NULL) { + memcpy(bitmap->data, &msgp->bitmap.data, bitmap->size); + } + g_free(msgp); + } else { + vfio_user_send_nowait(proxy, &msgp->msg.hdr, NULL, rsize); + } + + return 0; +} + static int vfio_user_get_info(VFIOProxy *proxy, struct vfio_device_info *info) { VFIOUserDeviceInfo msg; @@ -1251,5 +1432,41 @@ VFIODevIO vfio_dev_io_sock = { }; +static int vfio_user_io_dma_map(VFIOContainer *container, MemoryRegion *mr, + struct vfio_iommu_type1_dma_map *map) +{ + int fd = memory_region_get_fd(mr); + + /* + * map->vaddr enters as a QEMU process address + * make it either a file offset for mapped areas or 0 + */ + if (fd != -1) { + void *addr = (void *)(uintptr_t)map->vaddr; + + map->vaddr = qemu_ram_block_host_offset(mr->ram_block, addr); + } else { + map->vaddr = 0; + } + + return vfio_user_dma_map(container->proxy, map, fd, container->async_ops); +} + +static int vfio_user_io_dma_unmap(VFIOContainer *container, + struct vfio_iommu_type1_dma_unmap *unmap, + struct vfio_bitmap *bitmap) +{ + return vfio_user_dma_unmap(container->proxy, unmap, bitmap, + container->async_ops); +} + +static void vfio_user_io_wait_commit(VFIOContainer *container) +{ + vfio_user_wait_reqs(container->proxy); +} + VFIOContIO vfio_cont_io_sock = { + .dma_map = vfio_user_io_dma_map, + .dma_unmap = vfio_user_io_dma_unmap, + .wait_commit = vfio_user_io_wait_commit, }; -- 1.8.3.1