Used_memslots is shared by vhost kernel and user, it is equal to dev->mem->nregions, which is correct for vhost kernel, but not for vhost user, the latter one uses memory regions that have file descriptor. E.g. a VM has a vhost-user NIC and 8(vhost user memslot upper limit) memory slots, it will be failed to hotplug a new DIMM device since vhost_has_free_slot() finds no free slot left. It should be successful if only part of memory slots have file descriptor, so setting used memslots for vhost-user and vhost-kernel respectively.
Signed-off-by: Igor Mammedov <imamm...@redhat.com> Signed-off-by: Jay Zhou <jianjay.z...@huawei.com> Signed-off-by: Liuzhe <liuzh...@huawei.com> --- hw/virtio/vhost-backend.c | 15 +++++++- hw/virtio/vhost-user.c | 77 ++++++++++++++++++++++++++------------- hw/virtio/vhost.c | 13 +++---- include/hw/virtio/vhost-backend.h | 6 ++- 4 files changed, 75 insertions(+), 36 deletions(-) diff --git a/hw/virtio/vhost-backend.c b/hw/virtio/vhost-backend.c index 7f09efa..59def69 100644 --- a/hw/virtio/vhost-backend.c +++ b/hw/virtio/vhost-backend.c @@ -15,6 +15,8 @@ #include "hw/virtio/vhost-backend.h" #include "qemu/error-report.h" +static unsigned int vhost_kernel_used_memslots; + static int vhost_kernel_call(struct vhost_dev *dev, unsigned long int request, void *arg) { @@ -62,6 +64,11 @@ static int vhost_kernel_memslots_limit(struct vhost_dev *dev) return limit; } +static bool vhost_kernel_has_free_memslots(struct vhost_dev *dev) +{ + return vhost_kernel_used_memslots < vhost_kernel_memslots_limit(dev); +} + static int vhost_kernel_net_set_backend(struct vhost_dev *dev, struct vhost_vring_file *file) { @@ -233,11 +240,16 @@ static void vhost_kernel_set_iotlb_callback(struct vhost_dev *dev, qemu_set_fd_handler((uintptr_t)dev->opaque, NULL, NULL, NULL); } +static void vhost_kernel_set_used_memslots(struct vhost_dev *dev) +{ + vhost_kernel_used_memslots = dev->mem->nregions; +} + static const VhostOps kernel_ops = { .backend_type = VHOST_BACKEND_TYPE_KERNEL, .vhost_backend_init = vhost_kernel_init, .vhost_backend_cleanup = vhost_kernel_cleanup, - .vhost_backend_memslots_limit = vhost_kernel_memslots_limit, + .vhost_backend_has_free_memslots = vhost_kernel_has_free_memslots, .vhost_net_set_backend = vhost_kernel_net_set_backend, .vhost_scsi_set_endpoint = vhost_kernel_scsi_set_endpoint, .vhost_scsi_clear_endpoint = vhost_kernel_scsi_clear_endpoint, @@ -264,6 +276,7 @@ static const VhostOps kernel_ops = { #endif /* CONFIG_VHOST_VSOCK */ .vhost_set_iotlb_callback = vhost_kernel_set_iotlb_callback, .vhost_send_device_iotlb_msg = vhost_kernel_send_device_iotlb_msg, + .vhost_set_used_memslots = vhost_kernel_set_used_memslots, }; int vhost_set_backend_type(struct vhost_dev *dev, VhostBackendType backend_type) diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c index 8500562..11c7d52 100644 --- a/hw/virtio/vhost-user.c +++ b/hw/virtio/vhost-user.c @@ -122,6 +122,8 @@ static VhostUserMsg m __attribute__ ((unused)); /* The version of the protocol we support */ #define VHOST_USER_VERSION (0x1) +static bool vhost_user_free_memslots = true; + struct vhost_user { CharBackend *chr; int slave_fd; @@ -289,12 +291,43 @@ static int vhost_user_set_log_base(struct vhost_dev *dev, uint64_t base, return 0; } +static int vhost_user_prepare_msg(struct vhost_dev *dev, VhostUserMemory *mem, + int *fds) +{ + int i, fd; + + vhost_user_free_memslots = true; + for (i = 0, mem->nregions = 0; i < dev->mem->nregions; ++i) { + struct vhost_memory_region *reg = dev->mem->regions + i; + ram_addr_t offset; + MemoryRegion *mr; + + assert((uintptr_t)reg->userspace_addr == reg->userspace_addr); + mr = memory_region_from_host((void *)(uintptr_t)reg->userspace_addr, + &offset); + fd = memory_region_get_fd(mr); + if (fd > 0) { + if (mem->nregions == VHOST_MEMORY_MAX_NREGIONS) { + vhost_user_free_memslots = false; + return -1; + } + + mem->regions[mem->nregions].userspace_addr = reg->userspace_addr; + mem->regions[mem->nregions].memory_size = reg->memory_size; + mem->regions[mem->nregions].guest_phys_addr = reg->guest_phys_addr; + mem->regions[mem->nregions].mmap_offset = offset; + fds[mem->nregions++] = fd; + } + } + + return 0; +} + static int vhost_user_set_mem_table(struct vhost_dev *dev, struct vhost_memory *mem) { int fds[VHOST_MEMORY_MAX_NREGIONS]; - int i, fd; - size_t fd_num = 0; + size_t fd_num; bool reply_supported = virtio_has_feature(dev->protocol_features, VHOST_USER_PROTOCOL_F_REPLY_ACK); @@ -307,29 +340,12 @@ static int vhost_user_set_mem_table(struct vhost_dev *dev, msg.flags |= VHOST_USER_NEED_REPLY_MASK; } - for (i = 0; i < dev->mem->nregions; ++i) { - struct vhost_memory_region *reg = dev->mem->regions + i; - ram_addr_t offset; - MemoryRegion *mr; - - assert((uintptr_t)reg->userspace_addr == reg->userspace_addr); - mr = memory_region_from_host((void *)(uintptr_t)reg->userspace_addr, - &offset); - fd = memory_region_get_fd(mr); - if (fd > 0) { - if (fd_num == VHOST_MEMORY_MAX_NREGIONS) { - error_report("Failed preparing vhost-user memory table msg"); - return -1; - } - msg.payload.memory.regions[fd_num].userspace_addr = reg->userspace_addr; - msg.payload.memory.regions[fd_num].memory_size = reg->memory_size; - msg.payload.memory.regions[fd_num].guest_phys_addr = reg->guest_phys_addr; - msg.payload.memory.regions[fd_num].mmap_offset = offset; - fds[fd_num++] = fd; - } + if (vhost_user_prepare_msg(dev, &msg.payload.memory, fds) < 0) { + error_report("Failed preparing vhost-user memory table msg"); + return -1; } - msg.payload.memory.nregions = fd_num; + fd_num = msg.payload.memory.nregions; if (!fd_num) { error_report("Failed initializing vhost-user memory map, " @@ -818,9 +834,9 @@ static int vhost_user_get_vq_index(struct vhost_dev *dev, int idx) return idx; } -static int vhost_user_memslots_limit(struct vhost_dev *dev) +static bool vhost_user_has_free_memslots(struct vhost_dev *dev) { - return VHOST_MEMORY_MAX_NREGIONS; + return vhost_user_free_memslots; } static bool vhost_user_requires_shm_log(struct vhost_dev *dev) @@ -925,11 +941,19 @@ static void vhost_user_set_iotlb_callback(struct vhost_dev *dev, int enabled) /* No-op as the receive channel is not dedicated to IOTLB messages. */ } +static void vhost_user_set_used_memslots(struct vhost_dev *dev) +{ + int fds[VHOST_MEMORY_MAX_NREGIONS]; + VhostUserMsg msg; + + vhost_user_prepare_msg(dev, &msg.payload.memory, fds); +} + const VhostOps user_ops = { .backend_type = VHOST_BACKEND_TYPE_USER, .vhost_backend_init = vhost_user_init, .vhost_backend_cleanup = vhost_user_cleanup, - .vhost_backend_memslots_limit = vhost_user_memslots_limit, + .vhost_backend_has_free_memslots = vhost_user_has_free_memslots, .vhost_set_log_base = vhost_user_set_log_base, .vhost_set_mem_table = vhost_user_set_mem_table, .vhost_set_vring_addr = vhost_user_set_vring_addr, @@ -951,4 +975,5 @@ const VhostOps user_ops = { .vhost_net_set_mtu = vhost_user_net_set_mtu, .vhost_set_iotlb_callback = vhost_user_set_iotlb_callback, .vhost_send_device_iotlb_msg = vhost_user_send_device_iotlb_msg, + .vhost_set_used_memslots = vhost_user_set_used_memslots, }; diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c index 69b3599..f970ab7 100644 --- a/hw/virtio/vhost.c +++ b/hw/virtio/vhost.c @@ -43,20 +43,19 @@ static struct vhost_log *vhost_log; static struct vhost_log *vhost_log_shm; -static unsigned int used_memslots; static QLIST_HEAD(, vhost_dev) vhost_devices = QLIST_HEAD_INITIALIZER(vhost_devices); bool vhost_has_free_slot(void) { - unsigned int slots_limit = ~0U; struct vhost_dev *hdev; QLIST_FOREACH(hdev, &vhost_devices, entry) { - unsigned int r = hdev->vhost_ops->vhost_backend_memslots_limit(hdev); - slots_limit = MIN(slots_limit, r); + if (!hdev->vhost_ops->vhost_backend_has_free_memslots(hdev)) { + return false; + } } - return slots_limit > used_memslots; + return true; } static void vhost_dev_sync_region(struct vhost_dev *dev, @@ -606,7 +605,7 @@ static void vhost_set_memory(MemoryListener *listener, dev->mem_changed_start_addr = MIN(dev->mem_changed_start_addr, start_addr); dev->mem_changed_end_addr = MAX(dev->mem_changed_end_addr, start_addr + size - 1); dev->memory_changed = true; - used_memslots = dev->mem->nregions; + dev->vhost_ops->vhost_set_used_memslots(dev); } static bool vhost_section(MemoryRegionSection *section) @@ -1333,7 +1332,7 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque, memory_listener_register(&hdev->memory_listener, &address_space_memory); QLIST_INSERT_HEAD(&vhost_devices, hdev, entry); - if (used_memslots > hdev->vhost_ops->vhost_backend_memslots_limit(hdev)) { + if (!hdev->vhost_ops->vhost_backend_has_free_memslots(hdev)) { error_report("vhost backend memory slots limit is less" " than current number of present memory slots"); r = -1; diff --git a/include/hw/virtio/vhost-backend.h b/include/hw/virtio/vhost-backend.h index a7a5f22..ea01d5f 100644 --- a/include/hw/virtio/vhost-backend.h +++ b/include/hw/virtio/vhost-backend.h @@ -31,7 +31,7 @@ struct vhost_iotlb_msg; typedef int (*vhost_backend_init)(struct vhost_dev *dev, void *opaque); typedef int (*vhost_backend_cleanup)(struct vhost_dev *dev); -typedef int (*vhost_backend_memslots_limit)(struct vhost_dev *dev); +typedef bool (*vhost_backend_has_free_memslots)(struct vhost_dev *dev); typedef int (*vhost_net_set_backend_op)(struct vhost_dev *dev, struct vhost_vring_file *file); @@ -84,12 +84,13 @@ typedef void (*vhost_set_iotlb_callback_op)(struct vhost_dev *dev, int enabled); typedef int (*vhost_send_device_iotlb_msg_op)(struct vhost_dev *dev, struct vhost_iotlb_msg *imsg); +typedef void (*vhost_set_used_memslots_op)(struct vhost_dev *dev); typedef struct VhostOps { VhostBackendType backend_type; vhost_backend_init vhost_backend_init; vhost_backend_cleanup vhost_backend_cleanup; - vhost_backend_memslots_limit vhost_backend_memslots_limit; + vhost_backend_has_free_memslots vhost_backend_has_free_memslots; vhost_net_set_backend_op vhost_net_set_backend; vhost_net_set_mtu_op vhost_net_set_mtu; vhost_scsi_set_endpoint_op vhost_scsi_set_endpoint; @@ -118,6 +119,7 @@ typedef struct VhostOps { vhost_vsock_set_running_op vhost_vsock_set_running; vhost_set_iotlb_callback_op vhost_set_iotlb_callback; vhost_send_device_iotlb_msg_op vhost_send_device_iotlb_msg; + vhost_set_used_memslots_op vhost_set_used_memslots; } VhostOps; extern const VhostOps user_ops; -- 1.8.3.1