diff options
| -rw-r--r-- | arch/um/drivers/Kconfig | 7 | ||||
| -rw-r--r-- | arch/um/drivers/Makefile | 1 | ||||
| -rw-r--r-- | arch/um/drivers/vhost_user.h | 102 | ||||
| -rw-r--r-- | arch/um/drivers/virtio_uml.c | 1002 | ||||
| -rw-r--r-- | arch/um/include/asm/irq.h | 5 | ||||
| -rw-r--r-- | arch/um/include/shared/os.h | 5 | ||||
| -rw-r--r-- | arch/um/kernel/ksyms.c | 2 | ||||
| -rw-r--r-- | arch/um/kernel/mem.c | 1 | ||||
| -rw-r--r-- | arch/um/kernel/physmem.c | 1 | ||||
| -rw-r--r-- | arch/um/kernel/um_arch.c | 1 | ||||
| -rw-r--r-- | arch/um/os-Linux/file.c | 44 |
11 files changed, 1169 insertions, 2 deletions
diff --git a/arch/um/drivers/Kconfig b/arch/um/drivers/Kconfig index 2638e46f50cc..fea5a0d522dc 100644 --- a/arch/um/drivers/Kconfig +++ b/arch/um/drivers/Kconfig @@ -335,3 +335,10 @@ config UML_NET_SLIRP Startup example: "eth0=slirp,FE:FD:01:02:03:04,/usr/local/bin/slirp" endmenu + +config VIRTIO_UML + tristate "UML driver for virtio devices" + select VIRTIO + help + This driver provides support for virtio based paravirtual device + drivers over vhost-user sockets. diff --git a/arch/um/drivers/Makefile b/arch/um/drivers/Makefile index 693319839f69..3edf0a7cfd25 100644 --- a/arch/um/drivers/Makefile +++ b/arch/um/drivers/Makefile @@ -61,6 +61,7 @@ obj-$(CONFIG_XTERM_CHAN) += xterm.o xterm_kern.o obj-$(CONFIG_UML_WATCHDOG) += harddog.o obj-$(CONFIG_BLK_DEV_COW_COMMON) += cow_user.o obj-$(CONFIG_UML_RANDOM) += random.o +obj-$(CONFIG_VIRTIO_UML) += virtio_uml.o # pcap_user.o must be added explicitly. USER_OBJS := fd.o null.o pty.o tty.o xterm.o slip_common.o pcap_user.o vde_user.o vector_user.o diff --git a/arch/um/drivers/vhost_user.h b/arch/um/drivers/vhost_user.h new file mode 100644 index 000000000000..2a9829b0782b --- /dev/null +++ b/arch/um/drivers/vhost_user.h @@ -0,0 +1,102 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* Vhost-user protocol */ + +#ifndef __VHOST_USER_H__ +#define __VHOST_USER_H__ + +/* Message flags */ +#define VHOST_USER_FLAG_REPLY BIT(2) +/* Feature bits */ +#define VHOST_USER_F_PROTOCOL_FEATURES 30 +/* Protocol feature bits */ +#define VHOST_USER_PROTOCOL_F_CONFIG 9 +/* Vring state index masks */ +#define VHOST_USER_VRING_INDEX_MASK 0xff +#define VHOST_USER_VRING_POLL_MASK BIT(8) + +/* Supported version */ +#define VHOST_USER_VERSION 1 +/* Supported transport features */ +#define VHOST_USER_SUPPORTED_F BIT_ULL(VHOST_USER_F_PROTOCOL_FEATURES) +/* Supported protocol features */ +#define VHOST_USER_SUPPORTED_PROTOCOL_F BIT_ULL(VHOST_USER_PROTOCOL_F_CONFIG) + +enum vhost_user_request { + VHOST_USER_GET_FEATURES = 1, + VHOST_USER_SET_FEATURES = 2, + VHOST_USER_SET_OWNER = 3, + VHOST_USER_RESET_OWNER = 4, + VHOST_USER_SET_MEM_TABLE = 5, + VHOST_USER_SET_LOG_BASE = 6, + VHOST_USER_SET_LOG_FD = 7, + VHOST_USER_SET_VRING_NUM = 8, + VHOST_USER_SET_VRING_ADDR = 9, + VHOST_USER_SET_VRING_BASE = 10, + VHOST_USER_GET_VRING_BASE = 11, + VHOST_USER_SET_VRING_KICK = 12, + VHOST_USER_SET_VRING_CALL = 13, + VHOST_USER_SET_VRING_ERR = 14, + VHOST_USER_GET_PROTOCOL_FEATURES = 15, + VHOST_USER_SET_PROTOCOL_FEATURES = 16, + VHOST_USER_GET_QUEUE_NUM = 17, + VHOST_USER_SET_VRING_ENABLE = 18, + VHOST_USER_SEND_RARP = 19, + VHOST_USER_NET_SEND_MTU = 20, + VHOST_USER_SET_SLAVE_REQ_FD = 21, + VHOST_USER_IOTLB_MSG = 22, + VHOST_USER_SET_VRING_ENDIAN = 23, + VHOST_USER_GET_CONFIG = 24, + VHOST_USER_SET_CONFIG = 25, +}; + +struct vhost_user_header { + u32 request; /* Use enum vhost_user_request */ + u32 flags; + u32 size; +} __packed; + +struct vhost_user_config { + u32 offset; + u32 size; + u32 flags; + u8 payload[0]; /* Variable length */ +} __packed; + +struct vhost_user_vring_state { + u32 index; + u32 num; +} __packed; + +struct vhost_user_vring_addr { + u32 index; + u32 flags; + u64 desc, used, avail, log; +} __packed; + +struct vhost_user_mem_region { + u64 guest_addr; + u64 size; + u64 user_addr; + u64 mmap_offset; +} __packed; + +struct vhost_user_mem_regions { + u32 num; + u32 padding; + struct vhost_user_mem_region regions[2]; /* Currently supporting 2 */ +} __packed; + +union vhost_user_payload { + u64 integer; + struct vhost_user_config config; + struct vhost_user_vring_state vring_state; + struct vhost_user_vring_addr vring_addr; + struct vhost_user_mem_regions mem_regions; +}; + +struct vhost_user_msg { + struct vhost_user_header header; + union vhost_user_payload payload; +} __packed; + +#endif diff --git a/arch/um/drivers/virtio_uml.c b/arch/um/drivers/virtio_uml.c new file mode 100644 index 000000000000..a63da4fcc5ae --- /dev/null +++ b/arch/um/drivers/virtio_uml.c @@ -0,0 +1,1002 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Virtio vhost-user driver + * + * Copyright(c) 2019 Intel Corporation + * + * This module allows virtio devices to be used over a vhost-user socket. + * + * Guest devices can be instantiated by kernel module or command line + * parameters. One device will be created for each parameter. Syntax: + * + * [virtio_uml.]device=<socket>:<virtio_id>[:<platform_id>] + * where: + * <socket> := vhost-user socket path to connect + * <virtio_id> := virtio device id (as in virtio_ids.h) + * <platform_id> := (optional) platform device id + * + * example: + * virtio_uml.device=/var/uml.socket:1 + * + * Based on Virtio MMIO driver by Pawel Moll, copyright 2011-2014, ARM Ltd. + */ +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/virtio.h> +#include <linux/virtio_config.h> +#include <linux/virtio_ring.h> +#include <shared/as-layout.h> +#include <irq_kern.h> +#include <init.h> +#include <os.h> +#include "vhost_user.h" + +/* Workaround due to a conflict between irq_user.h and irqreturn.h */ +#ifdef IRQ_NONE +#undef IRQ_NONE +#endif + +#define MAX_SUPPORTED_QUEUE_SIZE 256 + +#define to_virtio_uml_device(_vdev) \ + container_of(_vdev, struct virtio_uml_device, vdev) + +struct virtio_uml_device { + struct virtio_device vdev; + struct platform_device *pdev; + + int sock; + u64 features; + u64 protocol_features; + u8 status; +}; + +struct virtio_uml_vq_info { + int kick_fd, call_fd; + char name[32]; +}; + +extern unsigned long long physmem_size, highmem; + +#define vu_err(vu_dev, ...) dev_err(&(vu_dev)->pdev->dev, __VA_ARGS__) + +/* Vhost-user protocol */ + +static int full_sendmsg_fds(int fd, const void *buf, unsigned int len, + const int *fds, unsigned int fds_num) +{ + int rc; + + do { + rc = os_sendmsg_fds(fd, buf, len, fds, fds_num); + if (rc > 0) { + buf += rc; + len -= rc; + fds = NULL; + fds_num = 0; + } + } while (len && (rc >= 0 || rc == -EINTR)); + + if (rc < 0) + return rc; + return 0; +} + +static int full_read(int fd, void *buf, int len) +{ + int rc; + + do { + rc = os_read_file(fd, buf, len); + if (rc > 0) { + buf += rc; + len -= rc; + } + } while (len && (rc > 0 || rc == -EINTR)); + + if (rc < 0) + return rc; + if (rc == 0) + return -ECONNRESET; + return 0; +} + +static int vhost_user_recv_header(struct virtio_uml_device *vu_dev, + struct vhost_user_msg *msg) +{ + size_t size = sizeof(msg->header); + int rc; + + rc = full_read(vu_dev->sock, (void *) msg, size); + if (rc) + return rc; + if (msg->header.flags != (VHOST_USER_FLAG_REPLY | VHOST_USER_VERSION)) + return -EPROTO; + return 0; +} + +static int vhost_user_recv(struct virtio_uml_device *vu_dev, + struct vhost_user_msg *msg, + size_t max_payload_size) +{ + size_t size; + int rc = vhost_user_recv_header(vu_dev, msg); + + if (rc) + return rc; + size = msg->header.size; + if (size > max_payload_size) + return -EPROTO; + return full_read(vu_dev->sock, (void *) &msg->payload, size); +} + +static int vhost_user_recv_u64(struct virtio_uml_device *vu_dev, + u64 *value) +{ + struct vhost_user_msg msg; + int rc = vhost_user_recv(vu_dev, &msg, sizeof(msg.payload.integer)); + + if (rc) + return rc; + if (msg.header.size != sizeof(msg.payload.integer)) + return -EPROTO; + *value = msg.payload.integer; + return 0; +} + +static int vhost_user_send(struct virtio_uml_device *vu_dev, + struct vhost_user_msg *msg, + int *fds, size_t num_fds) +{ + size_t size = sizeof(msg->header) + msg->header.size; + + msg->header.flags |= VHOST_USER_VERSION; + return full_sendmsg_fds(vu_dev->sock, msg, size, fds, num_fds); +} + +static int vhost_user_send_no_payload(struct virtio_uml_device *vu_dev, + u32 request) +{ + struct vhost_user_msg msg = { + .header.request = request, + }; + + return vhost_user_send(vu_dev, &msg, NULL, 0); +} + +static int vhost_user_send_u64(struct virtio_uml_device *vu_dev, + u32 request, u64 value) +{ + struct vhost_user_msg msg = { + .header.request = request, + .header.size = sizeof(msg.payload.integer), + .payload.integer = value, + }; + + return vhost_user_send(vu_dev, &msg, NULL, 0); +} + +static int vhost_user_set_owner(struct virtio_uml_device *vu_dev) +{ + return vhost_user_send_no_payload(vu_dev, VHOST_USER_SET_OWNER); +} + +static int vhost_user_get_features(struct virtio_uml_device *vu_dev, + u64 *features) +{ + int rc = vhost_user_send_no_payload(vu_dev, VHOST_USER_GET_FEATURES); + + if (rc) + return rc; + return vhost_user_recv_u64(vu_dev, features); +} + +static int vhost_user_set_features(struct virtio_uml_device *vu_dev, + u64 features) +{ + return vhost_user_send_u64(vu_dev, VHOST_USER_SET_FEATURES, features); +} + +static int vhost_user_get_protocol_features(struct virtio_uml_device *vu_dev, + u64 *protocol_features) +{ + int rc = vhost_user_send_no_payload(vu_dev, + VHOST_USER_GET_PROTOCOL_FEATURES); + + if (rc) + return rc; + return vhost_user_recv_u64(vu_dev, protocol_features); +} + +static int vhost_user_set_protocol_features(struct virtio_uml_device *vu_dev, + u64 protocol_features) +{ + return vhost_user_send_u64(vu_dev, VHOST_USER_SET_PROTOCOL_FEATURES, + protocol_features); +} + +static int vhost_user_init(struct virtio_uml_device *vu_dev) +{ + int rc = vhost_user_set_owner(vu_dev); + + if (rc) + return rc; + rc = vhost_user_get_features(vu_dev, &vu_dev->features); + if (rc) + return rc; + + if (vu_dev->features & BIT_ULL(VHOST_USER_F_PROTOCOL_FEATURES)) { + rc = vhost_user_get_protocol_features(vu_dev, + &vu_dev->protocol_features); + if (rc) + return rc; + vu_dev->protocol_features &= VHOST_USER_SUPPORTED_PROTOCOL_F; + rc = vhost_user_set_protocol_features(vu_dev, + vu_dev->protocol_features); + } + return rc; +} + +static void vhost_user_get_config(struct virtio_uml_device *vu_dev, + u32 offset, void *buf, u32 len) +{ + u32 cfg_size = offset + len; + struct vhost_user_msg *msg; + size_t payload_size = sizeof(msg->payload.config) + cfg_size; + size_t msg_size = sizeof(msg->header) + payload_size; + int rc; + + if (!(vu_dev->protocol_features & + BIT_ULL(VHOST_USER_PROTOCOL_F_CONFIG))) + return; + + msg = kzalloc(msg_size, GFP_KERNEL); + if (!msg) + return; + msg->header.request = VHOST_USER_GET_CONFIG; + msg->header.size = payload_size; + msg->payload.config.offset = 0; + msg->payload.config.size = cfg_size; + + rc = vhost_user_send(vu_dev, msg, NULL, 0); + if (rc) { + vu_err(vu_dev, "sending VHOST_USER_GET_CONFIG failed: %d\n", + rc); + goto free; + } + + rc = vhost_user_recv(vu_dev, msg, msg_size); + if (rc) { + vu_err(vu_dev, + "receiving VHOST_USER_GET_CONFIG response failed: %d\n", + rc); + goto free; + } + + if (msg->header.size != payload_size || + msg->payload.config.size != cfg_size) { + rc = -EPROTO; + vu_err(vu_dev, + "Invalid VHOST_USER_GET_CONFIG sizes (payload %d expected %zu, config %u expected %u)\n", + msg->header.size, payload_size, + msg->payload.config.size, cfg_size); + goto free; + } + memcpy(buf, msg->payload.config.payload + offset, len); + +free: + kfree(msg); +} + +static void vhost_user_set_config(struct virtio_uml_device *vu_dev, + u32 offset, const void *buf, u32 len) +{ + struct vhost_user_msg *msg; + size_t payload_size = sizeof(msg->payload.config) + len; + size_t msg_size = sizeof(msg->header) + payload_size; + int rc; + + if (!(vu_dev->protocol_features & + BIT_ULL(VHOST_USER_PROTOCOL_F_CONFIG))) + return; + + msg = kzalloc(msg_size, GFP_KERNEL); + if (!msg) + return; + msg->header.request = VHOST_USER_SET_CONFIG; + msg->header.size = payload_size; + msg->payload.config.offset = offset; + msg->payload.config.size = len; + memcpy(msg->payload.config.payload, buf, len); + + rc = vhost_user_send(vu_dev, msg, NULL, 0); + if (rc) + vu_err(vu_dev, "sending VHOST_USER_SET_CONFIG failed: %d\n", + rc); + + kfree(msg); +} + +static int vhost_user_init_mem_region(u64 addr, u64 size, int *fd_out, + struct vhost_user_mem_region *region_out) +{ + unsigned long long mem_offset; + int rc = phys_mapping(addr, &mem_offset); + + if (WARN(rc < 0, "phys_mapping of 0x%llx returned %d\n", addr, rc)) + return -EFAULT; + *fd_out = rc; + region_out->guest_addr = addr; + region_out->user_addr = addr; + region_out->size = size; + region_out->mmap_offset = mem_offset; + + /* Ensure mapping is valid for the entire region */ + rc = phys_mapping(addr + size - 1, &mem_offset); + if (WARN(rc != *fd_out, "phys_mapping of 0x%llx failed: %d != %d\n", + addr + size - 1, rc, *fd_out)) + return -EFAULT; + return 0; +} + +static int vhost_user_set_mem_table(struct virtio_uml_device *vu_dev) +{ + struct vhost_user_msg msg = { + .header.request = VHOST_USER_SET_MEM_TABLE, + .header.size = sizeof(msg.payload.mem_regions), + .payload.mem_regions.num = 1, + }; + unsigned long reserved = uml_reserved - uml_physmem; + int fds[2]; + int rc; + + /* + * This is a bit tricky, see also the comment with setup_physmem(). + * + * Essentially, setup_physmem() uses a file to mmap() our physmem, + * but the code and data we *already* have is omitted. To us, this + * is no difference, since they both become part of our address + * space and memory consumption. To somebody looking in from the + * outside, however, it is different because the part of our memory + * consumption that's already part of the binary (code/data) is not + * mapped from the file, so it's not visible to another mmap from + * the file descriptor. + * + * Thus, don't advertise this space to the vhost-user slave. This + * means that the slave will likely abort or similar when we give + * it an address from the hidden range, since it's not marked as + * a valid address, but at least that way we detect the issue and + * don't just have the slave read an all-zeroes buffer from the + * shared memory file, or write something there that we can never + * see (depending on the direction of the virtqueue traffic.) + * + * Since we usually don't want to use .text for virtio buffers, + * this effectively means that you cannot use + * 1) global variables, which are in the .bss and not in the shm + * file-backed memory + * 2) the stack in some processes, depending on where they have + * their stack (or maybe only no interrupt stack?) + * + * The stack is already not typically valid for DMA, so this isn't + * much of a restriction, but global variables might be encountered. + * + * It might be possible to fix it by copying around the data that's + * between bss_start and where we map the file now, but it's not + * something that you typically encounter with virtio drivers, so + * it didn't seem worthwhile. + */ + rc = vhost_user_init_mem_region(reserved, physmem_size - reserved, + &fds[0], + &msg.payload.mem_regions.regions[0]); + + if (rc < 0) + return rc; + if (highmem) { + msg.payload.mem_regions.num++; + rc = vhost_user_init_mem_region(__pa(end_iomem), highmem, + &fds[1], &msg.payload.mem_regions.regions[1]); + if (rc < 0) + return rc; + } + + return vhost_user_send(vu_dev, &msg, fds, msg.payload.mem_regions.num); +} + +static int vhost_user_set_vring_state(struct virtio_uml_device *vu_dev, + u32 request, u32 index, u32 num) +{ + struct vhost_user_msg msg = { + .header.request = request, + .header.size = sizeof(msg.payload.vring_state), + .payload.vring_state.index = index, + .payload.vring_state.num = num, + }; + + return vhost_user_send(vu_dev, &msg, NULL, 0); +} + +static int vhost_user_set_vring_num(struct virtio_uml_device *vu_dev, + u32 index, u32 num) +{ + return vhost_user_set_vring_state(vu_dev, VHOST_USER_SET_VRING_NUM, + index, num); +} + +static int vhost_user_set_vring_base(struct virtio_uml_device *vu_dev, + u32 index, u32 offset) +{ + return vhost_user_set_vring_state(vu_dev, VHOST_USER_SET_VRING_BASE, + index, offset); +} + +static int vhost_user_set_vring_addr(struct virtio_uml_device *vu_dev, + u32 index, u64 desc, u64 used, u64 avail, + u64 log) +{ + struct vhost_user_msg msg = { + .header.request = VHOST_USER_SET_VRING_ADDR, + .header.size = sizeof(msg.payload.vring_addr), + .payload.vring_addr.index = index, + .payload.vring_addr.desc = desc, + .payload.vring_addr.used = used, + .payload.vring_addr.avail = avail, + .payload.vring_addr.log = log, + }; + + return vhost_user_send(vu_dev, &msg, NULL, 0); +} + +static int vhost_user_set_vring_fd(struct virtio_uml_device *vu_dev, + u32 request, int index, int fd) +{ + struct vhost_user_msg msg = { + .header.request = request, + .header.size = sizeof(msg.payload.integer), + .payload.integer = index, + }; + + if (index & ~VHOST_USER_VRING_INDEX_MASK) + return -EINVAL; + if (fd < 0) { + msg.payload.integer |= VHOST_USER_VRING_POLL_MASK; + return vhost_user_send(vu_dev, &msg, NULL, 0); + } + return vhost_user_send(vu_dev, &msg, &fd, 1); +} + +static int vhost_user_set_vring_call(struct virtio_uml_device *vu_dev, + int index, int fd) +{ + return vhost_user_set_vring_fd(vu_dev, VHOST_USER_SET_VRING_CALL, + index, fd); +} + +static int vhost_user_set_vring_kick(struct virtio_uml_device *vu_dev, + int index, int fd) +{ + return vhost_user_set_vring_fd(vu_dev, VHOST_USER_SET_VRING_KICK, + index, fd); +} + +static int vhost_user_set_vring_enable(struct virtio_uml_device *vu_dev, + u32 index, bool enable) +{ + if (!(vu_dev->features & BIT_ULL(VHOST_USER_F_PROTOCOL_FEATURES))) + return 0; + + return vhost_user_set_vring_state(vu_dev, VHOST_USER_SET_VRING_ENABLE, + index, enable); +} + + +/* Virtio interface */ + +static bool vu_notify(struct virtqueue *vq) +{ + struct virtio_uml_vq_info *info = vq->priv; + const uint64_t n = 1; + int rc; + + do { + rc = os_write_file(info->kick_fd, &n, sizeof(n)); + } while (rc == -EINTR); + return !WARN(rc != sizeof(n), "write returned %d\n", rc); +} + +static irqreturn_t vu_interrupt(int irq, void *opaque) +{ + struct virtqueue *vq = opaque; + struct virtio_uml_vq_info *info = vq->priv; + uint64_t n; + int rc; + irqreturn_t ret = IRQ_NONE; + + do { + rc = os_read_file(info->call_fd, &n, sizeof(n)); + if (rc == sizeof(n)) + ret |= vring_interrupt(irq, vq); + } while (rc == sizeof(n) || rc == -EINTR); + WARN(rc != -EAGAIN, "read returned %d\n", rc); + return ret; +} + + +static void vu_get(struct virtio_device *vdev, unsigned offset, + void *buf, unsigned len) +{ + struct virtio_uml_device *vu_dev = to_virtio_uml_device(vdev); + + vhost_user_get_config(vu_dev, offset, buf, len); +} + +static void vu_set(struct virtio_device *vdev, unsigned offset, + const void *buf, unsigned len) +{ + struct virtio_uml_device *vu_dev = to_virtio_uml_device(vdev); + + vhost_user_set_config(vu_dev, offset, buf, len); +} + +static u8 vu_get_status(struct virtio_device *vdev) +{ + struct virtio_uml_device *vu_dev = to_virtio_uml_device(vdev); + + return vu_dev->status; +} + +static void vu_set_status(struct virtio_device *vdev, u8 status) +{ + struct virtio_uml_device *vu_dev = to_virtio_uml_device(vdev); + + vu_dev->status = status; +} + +static void vu_reset(struct virtio_device *vdev) +{ + struct virtio_uml_device *vu_dev = to_virtio_uml_device(vdev); + + vu_dev->status = 0; +} + +static void vu_del_vq(struct virtqueue *vq) +{ + struct virtio_uml_vq_info *info = vq->priv; + + um_free_irq(VIRTIO_IRQ, vq); + + os_close_file(info->call_fd); + os_close_file(info->kick_fd); + + vring_del_virtqueue(vq); + kfree(info); +} + +static void vu_del_vqs(struct virtio_device *vdev) +{ + struct virtio_uml_device *vu_dev = to_virtio_uml_device(vdev); + struct virtqueue *vq, *n; + u64 features; + + /* Note: reverse order as a workaround to a decoding bug in snabb */ + list_for_each_entry_reverse(vq, &vdev->vqs, list) + WARN_ON(vhost_user_set_vring_enable(vu_dev, vq->index, false)); + + /* Ensure previous messages have been processed */ + WARN_ON(vhost_user_get_features(vu_dev, &features)); + + list_for_each_entry_safe(vq, n, &vdev->vqs, list) + vu_del_vq(vq); +} + +static int vu_setup_vq_call_fd(struct virtio_uml_device *vu_dev, + struct virtqueue *vq) +{ + struct virtio_uml_vq_info *info = vq->priv; + int call_fds[2]; + int rc; + + /* Use a pipe for call fd, since SIGIO is not supported for eventfd */ + rc = os_pipe(call_fds, true, true); + if (rc < 0) + return rc; + + info->call_fd = call_fds[0]; + rc = um_request_irq(VIRTIO_IRQ, info->call_fd, IRQ_READ, + vu_interrupt, IRQF_SHARED, info->name, vq); + if (rc) + goto close_both; + + rc = vhost_user_set_vring_call(vu_dev, vq->index, call_fds[1]); + if (rc) + goto release_irq; + + goto out; + +release_irq: + um_free_irq(VIRTIO_IRQ, vq); +close_both: + os_close_file(call_fds[0]); +out: + /* Close (unused) write end of call fds */ + os_close_file(call_fds[1]); + + return rc; +} + +static struct virtqueue *vu_setup_vq(struct virtio_device *vdev, + unsigned index, vq_callback_t *callback, + const char *name, bool ctx) +{ + struct virtio_uml_device *vu_dev = to_virtio_uml_device(vdev); + struct platform_device *pdev = vu_dev->pdev; + struct virtio_uml_vq_info *info; + struct virtqueue *vq; + int num = MAX_SUPPORTED_QUEUE_SIZE; + int rc; + + info = kzalloc(sizeof(*info), GFP_KERNEL); + if (!info) { + rc = -ENOMEM; + goto error_kzalloc; + } + snprintf(info->name, sizeof(info->name), "%s.%d-%s", pdev->name, + pdev->id, name); + + vq = vring_create_virtqueue(index, num, PAGE_SIZE, vdev, true, true, + ctx, vu_notify, callback, info->name); + if (!vq) { + rc = -ENOMEM; + goto error_create; + } + vq->priv = info; + num = virtqueue_get_vring_size(vq); + + rc = os_eventfd(0, 0); + if (rc < 0) + goto error_kick; + info->kick_fd = rc; + + rc = vu_setup_vq_call_fd(vu_dev, vq); + if (rc) + goto error_call; + + rc = vhost_user_set_vring_num(vu_dev, index, num); + if (rc) + goto error_setup; + + rc = vhost_user_set_vring_base(vu_dev, index, 0); + if (rc) + goto error_setup; + + rc = vhost_user_set_vring_addr(vu_dev, index, + virtqueue_get_desc_addr(vq), + virtqueue_get_used_addr(vq), + virtqueue_get_avail_addr(vq), + (u64) -1); + if (rc) + goto error_setup; + + return vq; + +error_setup: + um_free_irq(VIRTIO_IRQ, vq); + os_close_file(info->call_fd); +error_call: + os_close_file(info->kick_fd); +error_kick: + vring_del_virtqueue(vq); +error_create: + kfree(info); +error_kzalloc: + return ERR_PTR(rc); +} + +static int vu_find_vqs(struct virtio_device *vdev, unsigned nvqs, + struct virtqueue *vqs[], vq_callback_t *callbacks[], + const char * const names[], const bool *ctx, + struct irq_affinity *desc) +{ + struct virtio_uml_device *vu_dev = to_virtio_uml_device(vdev); + int i, queue_idx = 0, rc; + struct virtqueue *vq; + + rc = vhost_user_set_mem_table(vu_dev); + if (rc) + return rc; + + for (i = 0; i < nvqs; ++i) { + if (!names[i]) { + vqs[i] = NULL; + continue; + } + + vqs[i] = vu_setup_vq(vdev, queue_idx++, callbacks[i], names[i], + ctx ? ctx[i] : false); + if (IS_ERR(vqs[i])) { + rc = PTR_ERR(vqs[i]); + goto error_setup; + } + } + + list_for_each_entry(vq, &vdev->vqs, list) { + struct virtio_uml_vq_info *info = vq->priv; + + rc = vhost_user_set_vring_kick(vu_dev, vq->index, + info->kick_fd); + if (rc) + goto error_setup; + + rc = vhost_user_set_vring_enable(vu_dev, vq->index, true); + if (rc) + goto error_setup; + } + + return 0; + +error_setup: + vu_del_vqs(vdev); + return rc; +} + +static u64 vu_get_features(struct virtio_device *vdev) +{ + struct virtio_uml_device *vu_dev = to_virtio_uml_device(vdev); + + return vu_dev->features; +} + +static int vu_finalize_features(struct virtio_device *vdev) +{ + struct virtio_uml_device *vu_dev = to_virtio_uml_device(vdev); + u64 supported = vdev->features & VHOST_USER_SUPPORTED_F; + + vring_transport_features(vdev); + vu_dev->features = vdev->features | supported; + + return vhost_user_set_features(vu_dev, vu_dev->features); +} + +static const char *vu_bus_name(struct virtio_device *vdev) +{ + struct virtio_uml_device *vu_dev = to_virtio_uml_device(vdev); + + return vu_dev->pdev->name; +} + +static const struct virtio_config_ops virtio_uml_config_ops = { + .get = vu_get, + .set = vu_set, + .get_status = vu_get_status, + .set_status = vu_set_status, + .reset = vu_reset, + .find_vqs = vu_find_vqs, + .del_vqs = vu_del_vqs, + .get_features = vu_get_features, + .finalize_features = vu_finalize_features, + .bus_name = vu_bus_name, +}; + + +static void virtio_uml_release_dev(struct device *d) +{ + struct virtio_device *vdev = + container_of(d, struct virtio_device, dev); + struct virtio_uml_device *vu_dev = to_virtio_uml_device(vdev); + + os_close_file(vu_dev->sock); +} + +/* Platform device */ + +struct virtio_uml_platform_data { + u32 virtio_device_id; + const char *socket_path; +}; + +static int virtio_uml_probe(struct platform_device *pdev) +{ + struct virtio_uml_platform_data *pdata = pdev->dev.platform_data; + struct virtio_uml_device *vu_dev; + int rc; + + if (!pdata) + return -EINVAL; + + vu_dev = devm_kzalloc(&pdev->dev, sizeof(*vu_dev), GFP_KERNEL); + if (!vu_dev) + return -ENOMEM; + + vu_dev->vdev.dev.parent = &pdev->dev; + vu_dev->vdev.dev.release = virtio_uml_release_dev; + vu_dev->vdev.config = &virtio_uml_config_ops; + vu_dev->vdev.id.device = pdata->virtio_device_id; + vu_dev->vdev.id.vendor = VIRTIO_DEV_ANY_ID; + vu_dev->pdev = pdev; + + do { + rc = os_connect_socket(pdata->socket_path); + } while (rc == -EINTR); + if (rc < 0) + return rc; + vu_dev->sock = rc; + + rc = vhost_user_init(vu_dev); + if (rc) + goto error_init; + + platform_set_drvdata(pdev, vu_dev); + + rc = register_virtio_device(&vu_dev->vdev); + if (rc) + put_device(&vu_dev->vdev.dev); + return rc; + +error_init: + os_close_file(vu_dev->sock); + return rc; +} + +static int virtio_uml_remove(struct platform_device *pdev) +{ + struct virtio_uml_device *vu_dev = platform_get_drvdata(pdev); + + unregister_virtio_device(&vu_dev->vdev); + return 0; +} + +/* Command line device list */ + +static void vu_cmdline_release_dev(struct device *d) +{ +} + +static struct device vu_cmdline_parent = { + .init_name = "virtio-uml-cmdline", + .release = vu_cmdline_release_dev, +}; + +static bool vu_cmdline_parent_registered; +static int vu_cmdline_id; + +static int vu_cmdline_set(const char *device, const struct kernel_param *kp) +{ + const char *ids = strchr(device, ':'); + unsigned int virtio_device_id; + int processed, consumed, err; + char *socket_path; + struct virtio_uml_platform_data pdata; + struct platform_device *pdev; + + if (!ids || ids == device) + return -EINVAL; + + processed = sscanf(ids, ":%u%n:%d%n", + &virtio_device_id, &consumed, + &vu_cmdline_id, &consumed); + + if (processed < 1 || ids[consumed]) + return -EINVAL; + + if (!vu_cmdline_parent_registered) { + err = device_register(&vu_cmdline_parent); + if (err) { + pr_err("Failed to register parent device!\n"); + put_device(&vu_cmdline_parent); + return err; + } + vu_cmdline_parent_registered = true; + } + + socket_path = kmemdup_nul(device, ids - device, GFP_KERNEL); + if (!socket_path) + return -ENOMEM; + + pdata.virtio_device_id = (u32) virtio_device_id; + pdata.socket_path = socket_path; + + pr_info("Registering device virtio-uml.%d id=%d at %s\n", + vu_cmdline_id, virtio_device_id, socket_path); + + pdev = platform_device_register_data(&vu_cmdline_parent, "virtio-uml", + vu_cmdline_id++, &pdata, + sizeof(pdata)); + err = PTR_ERR_OR_ZERO(pdev); + if (err) + goto free; + return 0; + +free: + kfree(socket_path); + return err; +} + +static int vu_cmdline_get_device(struct device *dev, void *data) +{ + struct platform_device *pdev = to_platform_device(dev); + struct virtio_uml_platform_data *pdata = pdev->dev.platform_data; + char *buffer = data; + unsigned int len = strlen(buffer); + + snprintf(buffer + len, PAGE_SIZE - len, "%s:%d:%d\n", + pdata->socket_path, pdata->virtio_device_id, pdev->id); + return 0; +} + +static int vu_cmdline_get(char *buffer, const struct kernel_param *kp) +{ + buffer[0] = '\0'; + if (vu_cmdline_parent_registered) + device_for_each_child(&vu_cmdline_parent, buffer, + vu_cmdline_get_device); + return strlen(buffer) + 1; +} + +static const struct kernel_param_ops vu_cmdline_param_ops = { + .set = vu_cmdline_set, + .get = vu_cmdline_get, +}; + +device_param_cb(device, &vu_cmdline_param_ops, NULL, S_IRUSR); +__uml_help(vu_cmdline_param_ops, +"virtio_uml.device=<socket>:<virtio_id>[:<platform_id>]\n" +" Configure a virtio device over a vhost-user socket.\n" +" See virtio_ids.h for a list of possible virtio device id values.\n" +" Optionally use a specific platform_device id.\n\n" +); + + +static int vu_unregister_cmdline_device(struct device *dev, void *data) +{ + struct platform_device *pdev = to_platform_device(dev); + struct virtio_uml_platform_data *pdata = pdev->dev.platform_data; + + kfree(pdata->socket_path); + platform_device_unregister(pdev); + return 0; +} + +static void vu_unregister_cmdline_devices(void) +{ + if (vu_cmdline_parent_registered) { + device_for_each_child(&vu_cmdline_parent, NULL, + vu_unregister_cmdline_device); + device_unregister(&vu_cmdline_parent); + vu_cmdline_parent_registered = false; + } +} + +/* Platform driver */ + +static const struct of_device_id virtio_uml_match[] = { + { .compatible = "virtio,uml", }, + { } +}; +MODULE_DEVICE_TABLE(of, virtio_uml_match); + +static struct platform_driver virtio_uml_driver = { + .probe = virtio_uml_probe, + .remove = virtio_uml_remove, + .driver = { + .name = "virtio-uml", + .of_match_table = virtio_uml_match, + }, +}; + +static int __init virtio_uml_init(void) +{ + return platform_driver_register(&virtio_uml_driver); +} + +static void __exit virtio_uml_exit(void) +{ + platform_driver_unregister(&virtio_uml_driver); + vu_unregister_cmdline_devices(); +} + +module_init(virtio_uml_init); +module_exit(virtio_uml_exit); +__uml_exitcall(virtio_uml_exit); + +MODULE_DESCRIPTION("UML driver for vhost-user virtio devices"); +MODULE_LICENSE("GPL"); diff --git a/arch/um/include/asm/irq.h b/arch/um/include/asm/irq.h index ce7a78c3bcf2..42c6205e2dc4 100644 --- a/arch/um/include/asm/irq.h +++ b/arch/um/include/asm/irq.h @@ -17,17 +17,18 @@ #define TELNETD_IRQ 12 #define XTERM_IRQ 13 #define RANDOM_IRQ 14 +#define VIRTIO_IRQ 15 #ifdef CONFIG_UML_NET_VECTOR -#define VECTOR_BASE_IRQ 15 +#define VECTOR_BASE_IRQ (VIRTIO_IRQ + 1) #define VECTOR_IRQ_SPACE 8 #define LAST_IRQ (VECTOR_IRQ_SPACE + VECTOR_BASE_IRQ - 1) #else -#define LAST_IRQ RANDOM_IRQ +#define LAST_IRQ VIRTIO_IRQ #endif diff --git a/arch/um/include/shared/os.h b/arch/um/include/shared/os.h index fa1909365666..d542dadcf22e 100644 --- a/arch/um/include/shared/os.h +++ b/arch/um/include/shared/os.h @@ -36,6 +36,8 @@ #define OS_LIB_PATH "/usr/lib/" #endif +#define OS_SENDMSG_MAX_FDS 8 + /* * types taken from stat_file() in hostfs_user.c * (if they are wrong here, they are wrong there...). @@ -176,6 +178,9 @@ extern unsigned os_major(unsigned long long dev); extern unsigned os_minor(unsigned long long dev); extern unsigned long long os_makedev(unsigned major, unsigned minor); extern int os_falloc_punch(int fd, unsigned long long offset, int count); +extern int os_eventfd(unsigned int initval, int flags); +extern int os_sendmsg_fds(int fd, const void *buf, unsigned int len, + const int *fds, unsigned int fds_num); /* start_up.c */ extern void os_early_checks(void); diff --git a/arch/um/kernel/ksyms.c b/arch/um/kernel/ksyms.c index 232b22307fdd..bdb90583f186 100644 --- a/arch/um/kernel/ksyms.c +++ b/arch/um/kernel/ksyms.c @@ -38,6 +38,8 @@ EXPORT_SYMBOL(run_helper); EXPORT_SYMBOL(os_major); EXPORT_SYMBOL(os_minor); EXPORT_SYMBOL(os_makedev); +EXPORT_SYMBOL(os_eventfd); +EXPORT_SYMBOL(os_sendmsg_fds); EXPORT_SYMBOL(add_sigio_fd); EXPORT_SYMBOL(ignore_sigio_fd); diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c index de58e976b9bc..f256be1d77bd 100644 --- a/arch/um/kernel/mem.c +++ b/arch/um/kernel/mem.c @@ -31,6 +31,7 @@ pgd_t swapper_pg_dir[PTRS_PER_PGD]; /* Initialized at boot time, and readonly after that */ unsigned long long highmem; +EXPORT_SYMBOL(highmem); int kmalloc_ok = 0; /* Used during early boot */ diff --git a/arch/um/kernel/physmem.c b/arch/um/kernel/physmem.c index 5bf56af4d5b9..870c80c88a97 100644 --- a/arch/um/kernel/physmem.c +++ b/arch/um/kernel/physmem.c @@ -143,6 +143,7 @@ int phys_mapping(unsigned long phys, unsigned long long *offset_out) return fd; } +EXPORT_SYMBOL(phys_mapping); static int __init uml_mem_setup(char *line, int *add) { diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c index a818ccef30ca..9de212bf4320 100644 --- a/arch/um/kernel/um_arch.c +++ b/arch/um/kernel/um_arch.c @@ -113,6 +113,7 @@ static int have_root __initdata = 0; /* Set in uml_mem_setup and modified in linux_main */ long long physmem_size = 32 * 1024 * 1024; +EXPORT_SYMBOL(physmem_size); static const char *usage_string = "User Mode Linux v%s\n" diff --git a/arch/um/os-Linux/file.c b/arch/um/os-Linux/file.c index f25b110d4e70..91f23035be08 100644 --- a/arch/um/os-Linux/file.c +++ b/arch/um/os-Linux/file.c @@ -15,6 +15,7 @@ #include <sys/sysmacros.h> #include <sys/un.h> #include <sys/types.h> +#include <sys/eventfd.h> #include <os.h> static void copy_stat(struct uml_stat *dst, const struct stat64 *src) @@ -620,3 +621,46 @@ int os_falloc_punch(int fd, unsigned long long offset, int len) return n; } +int os_eventfd(unsigned int initval, int flags) +{ + int fd = eventfd(initval, flags); + + if (fd < 0) + return -errno; + return fd; +} + +int os_sendmsg_fds(int fd, const void *buf, unsigned int len, const int *fds, + unsigned int fds_num) +{ + struct iovec iov = { + .iov_base = (void *) buf, + .iov_len = len, + }; + union { + char control[CMSG_SPACE(sizeof(*fds) * OS_SENDMSG_MAX_FDS)]; + struct cmsghdr align; + } u; + unsigned int fds_size = sizeof(*fds) * fds_num; + struct msghdr msg = { + .msg_iov = &iov, + .msg_iovlen = 1, + .msg_control = u.control, + .msg_controllen = CMSG_SPACE(fds_size), + }; + struct cmsghdr *cmsg = CMSG_FIRSTHDR(&msg); + int err; + + if (fds_num > OS_SENDMSG_MAX_FDS) + return -EINVAL; + memset(u.control, 0, sizeof(u.control)); + cmsg->cmsg_level = SOL_SOCKET; + cmsg->cmsg_type = SCM_RIGHTS; + cmsg->cmsg_len = CMSG_LEN(fds_size); + memcpy(CMSG_DATA(cmsg), fds, fds_size); + err = sendmsg(fd, &msg, 0); + + if (err < 0) + return -errno; + return err; +} |