/* $OpenBSD: vmm.c,v 1.44 2016/09/03 11:38:08 mlarkin Exp $ */ /* * Copyright (c) 2015 Mike Larkin * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #include /* nitems */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "vmd.h" #include "vmm.h" #include "loadfile.h" #include "pci.h" #include "virtio.h" #include "proc.h" #include "i8253.h" #include "i8259.h" #include "ns8250.h" #include "mc146818.h" io_fn_t ioports_map[MAX_PORTS]; void vmm_sighdlr(int, short, void *); int start_client_vmd(void); int opentap(void); int start_vm(struct imsg *, uint32_t *); int terminate_vm(struct vm_terminate_params *); int get_info_vm(struct privsep *, struct imsg *, int); int run_vm(int *, int *, struct vm_create_params *, struct vcpu_reg_state *); void *event_thread(void *); void *vcpu_run_loop(void *); int vcpu_exit(struct vm_run_params *); int vcpu_reset(uint32_t, uint32_t, struct vcpu_reg_state *); void create_memory_map(struct vm_create_params *); int alloc_guest_mem(struct vm_create_params *); int vmm_create_vm(struct vm_create_params *); void init_emulated_hw(struct vm_create_params *, int *, int *); void vcpu_exit_inout(struct vm_run_params *); uint8_t vcpu_exit_pci(struct vm_run_params *); int vmm_dispatch_parent(int, struct privsep_proc *, struct imsg *); void vmm_run(struct privsep *, struct privsep_proc *, void *); int vcpu_pic_intr(uint32_t, uint32_t, uint8_t); static struct vm_mem_range *find_gpa_range(struct vm_create_params *, paddr_t, size_t); int con_fd; struct vmd_vm *current_vm; extern struct vmd *env; extern char *__progname; pthread_mutex_t threadmutex; pthread_cond_t threadcond; pthread_cond_t vcpu_run_cond[VMM_MAX_VCPUS_PER_VM]; pthread_mutex_t vcpu_run_mtx[VMM_MAX_VCPUS_PER_VM]; uint8_t vcpu_hlt[VMM_MAX_VCPUS_PER_VM]; uint8_t vcpu_done[VMM_MAX_VCPUS_PER_VM]; static struct privsep_proc procs[] = { { "parent", PROC_PARENT, vmm_dispatch_parent }, }; /* * Represents a standard register set for an OS to be booted * as a flat 32 bit address space, before paging is enabled. * * NOT set here are: * RIP * RSP * GDTR BASE * * Specific bootloaders should clone this structure and override * those fields as needed. * * Note - CR3 and various bits in CR0 may be overridden by vmm(4) based on * features of the CPU in use. */ static const struct vcpu_reg_state vcpu_init_flat32 = { .vrs_gprs[VCPU_REGS_RFLAGS] = 0x2, .vrs_gprs[VCPU_REGS_RIP] = 0x0, .vrs_gprs[VCPU_REGS_RSP] = 0x0, .vrs_crs[VCPU_REGS_CR0] = CR0_CD | CR0_NW | CR0_ET | CR0_PE | CR0_PG, .vrs_crs[VCPU_REGS_CR3] = PML4_PAGE, .vrs_sregs[VCPU_REGS_CS] = { 0x8, 0xFFFFFFFF, 0xC09F, 0x0}, .vrs_sregs[VCPU_REGS_DS] = { 0x10, 0xFFFFFFFF, 0xC093, 0x0}, .vrs_sregs[VCPU_REGS_ES] = { 0x10, 0xFFFFFFFF, 0xC093, 0x0}, .vrs_sregs[VCPU_REGS_FS] = { 0x10, 0xFFFFFFFF, 0xC093, 0x0}, .vrs_sregs[VCPU_REGS_GS] = { 0x10, 0xFFFFFFFF, 0xC093, 0x0}, .vrs_sregs[VCPU_REGS_SS] = { 0x10, 0xFFFFFFFF, 0xC093, 0x0}, .vrs_gdtr = { 0x0, 0xFFFF, 0x0, 0x0}, .vrs_idtr = { 0x0, 0xFFFF, 0x0, 0x0}, .vrs_sregs[VCPU_REGS_LDTR] = { 0x0, 0xFFFF, 0x0082, 0x0}, .vrs_sregs[VCPU_REGS_TR] = { 0x0, 0xFFFF, 0x008B, 0x0}, }; pid_t vmm(struct privsep *ps, struct privsep_proc *p) { return (proc_run(ps, p, procs, nitems(procs), vmm_run, NULL)); } void vmm_run(struct privsep *ps, struct privsep_proc *p, void *arg) { if (config_init(ps->ps_env) == -1) fatal("failed to initialize configuration"); signal_del(&ps->ps_evsigchld); signal_set(&ps->ps_evsigchld, SIGCHLD, vmm_sighdlr, ps); signal_add(&ps->ps_evsigchld, NULL); #if 0 /* * pledge in the vmm process: * stdio - for malloc and basic I/O including events. * vmm - for the vmm ioctls and operations. * proc - for forking and maitaining vms. * recvfd - for disks, interfaces and other fds. */ /* XXX'ed pledge to hide it from grep as long as it's disabled */ if (XXX("stdio vmm recvfd proc", NULL) == -1) fatal("pledge"); #endif /* Get and terminate all running VMs */ get_info_vm(ps, NULL, 1); } int vmm_dispatch_parent(int fd, struct privsep_proc *p, struct imsg *imsg) { struct privsep *ps = p->p_ps; int res = 0, cmd = 0; struct vm_create_params vcp; struct vm_terminate_params vtp; struct vmop_result vmr; uint32_t id = 0; struct vmd_vm *vm; switch (imsg->hdr.type) { case IMSG_VMDOP_START_VM_REQUEST: IMSG_SIZE_CHECK(imsg, &vcp); memcpy(&vcp, imsg->data, sizeof(vcp)); res = config_getvm(ps, &vcp, imsg->fd, imsg->hdr.peerid); if (res == -1) { res = errno; cmd = IMSG_VMDOP_START_VM_RESPONSE; } break; case IMSG_VMDOP_START_VM_DISK: res = config_getdisk(ps, imsg); if (res == -1) { res = errno; cmd = IMSG_VMDOP_START_VM_RESPONSE; } break; case IMSG_VMDOP_START_VM_IF: res = config_getif(ps, imsg); if (res == -1) { res = errno; cmd = IMSG_VMDOP_START_VM_RESPONSE; } break; case IMSG_VMDOP_START_VM_END: res = start_vm(imsg, &id); cmd = IMSG_VMDOP_START_VM_RESPONSE; break; case IMSG_VMDOP_TERMINATE_VM_REQUEST: IMSG_SIZE_CHECK(imsg, &vtp); memcpy(&vtp, imsg->data, sizeof(vtp)); id = vtp.vtp_vm_id; res = terminate_vm(&vtp); cmd = IMSG_VMDOP_TERMINATE_VM_RESPONSE; if (res == 0) { /* Remove local reference */ vm = vm_getbyid(id); vm_remove(vm); } break; case IMSG_VMDOP_GET_INFO_VM_REQUEST: res = get_info_vm(ps, imsg, 0); cmd = IMSG_VMDOP_GET_INFO_VM_END_DATA; break; case IMSG_CTL_RESET: config_getreset(env, imsg); break; default: return (-1); } switch (cmd) { case 0: break; case IMSG_VMDOP_START_VM_RESPONSE: if (res != 0) { vm = vm_getbyvmid(imsg->hdr.peerid); vm_remove(vm); } case IMSG_VMDOP_TERMINATE_VM_RESPONSE: memset(&vmr, 0, sizeof(vmr)); vmr.vmr_result = res; vmr.vmr_id = id; if (proc_compose_imsg(ps, PROC_PARENT, -1, cmd, imsg->hdr.peerid, -1, &vmr, sizeof(vmr)) == -1) return (-1); break; default: if (proc_compose_imsg(ps, PROC_PARENT, -1, cmd, imsg->hdr.peerid, -1, &res, sizeof(res)) == -1) return (-1); break; } return (0); } void vmm_sighdlr(int sig, short event, void *arg) { struct privsep *ps = arg; int status; uint32_t vmid; pid_t pid; struct vmop_result vmr; struct vmd_vm *vm; struct vm_terminate_params vtp; switch (sig) { case SIGCHLD: do { pid = waitpid(-1, &status, WNOHANG); if (pid <= 0) continue; if (WIFEXITED(status) || WIFSIGNALED(status)) { vm = vm_getbypid(pid); if (vm == NULL) { /* * If the VM is gone already, it * got terminated via a * IMSG_VMDOP_TERMINATE_VM_REQUEST. */ continue; } vmid = vm->vm_params.vcp_id; vtp.vtp_vm_id = vmid; if (terminate_vm(&vtp) == 0) { memset(&vmr, 0, sizeof(vmr)); vmr.vmr_result = 0; vmr.vmr_id = vmid; vm_remove(vm); if (proc_compose_imsg(ps, PROC_PARENT, -1, IMSG_VMDOP_TERMINATE_VM_EVENT, 0, -1, &vmr, sizeof(vmr)) == -1) log_warnx("could not signal " "termination of VM %u to " "parent", vmid); } else log_warnx("could not terminate VM %u", vmid); } else fatalx("unexpected cause of SIGCHLD"); } while (pid > 0 || (pid == -1 && errno == EINTR)); break; default: fatalx("unexpected signal"); } } /* * vcpu_reset * * Requests vmm(4) to reset the VCPUs in the indicated VM to * the register state provided * * Parameters * vmid: VM ID to reset * vcpu_id: VCPU ID to reset * vrs: the register state to initialize * * Return values: * 0: success * !0 : ioctl to vmm(4) failed (eg, ENOENT if the supplied VM ID is not * valid) */ int vcpu_reset(uint32_t vmid, uint32_t vcpu_id, struct vcpu_reg_state *vrs) { struct vm_resetcpu_params vrp; memset(&vrp, 0, sizeof(vrp)); vrp.vrp_vm_id = vmid; vrp.vrp_vcpu_id = vcpu_id; memcpy(&vrp.vrp_init_state, vrs, sizeof(struct vcpu_reg_state)); log_debug("%s: resetting vcpu %d for vm %d", __func__, vcpu_id, vmid); if (ioctl(env->vmd_fd, VMM_IOC_RESETCPU, &vrp) < 0) return (errno); return (0); } /* * terminate_vm * * Requests vmm(4) to terminate the VM whose ID is provided in the * supplied vm_terminate_params structure (vtp->vtp_vm_id) * * Parameters * vtp: vm_create_params struct containing the ID of the VM to terminate * * Return values: * 0: success * !0 : ioctl to vmm(4) failed (eg, ENOENT if the supplied VM is not * valid) */ int terminate_vm(struct vm_terminate_params *vtp) { if (ioctl(env->vmd_fd, VMM_IOC_TERM, vtp) < 0) return (errno); return (0); } /* * opentap * * Opens the next available tap device, up to MAX_TAP. * * Returns a file descriptor to the tap node opened, or -1 if no tap * devices were available. */ int opentap(void) { int i, fd; char path[PATH_MAX]; for (i = 0; i < MAX_TAP; i++) { snprintf(path, PATH_MAX, "/dev/tap%d", i); fd = open(path, O_RDWR | O_NONBLOCK); if (fd != -1) return (fd); } return (-1); } /* * start_vm * * Starts a new VM with the creation parameters supplied (in the incoming * imsg->data field). This function performs a basic sanity check on the * incoming parameters and then performs the following steps to complete * the creation of the VM: * * 1. opens the VM disk image files specified in the VM creation parameters * 2. opens the specified VM kernel * 3. creates a VM console tty pair using openpty * 4. forks, passing the file descriptors opened in steps 1-3 to the child * vmd responsible for dropping privilege and running the VM's VCPU * loops. * * Parameters: * imsg: The incoming imsg body whose 'data' field is a vm_create_params * struct containing the VM creation parameters. * id: Returns the VM id as reported by the kernel. * * Return values: * 0: success * !0 : failure - typically an errno indicating the source of the failure */ int start_vm(struct imsg *imsg, uint32_t *id) { struct vm_create_params *vcp; struct vmd_vm *vm; size_t i; int ret = EINVAL; int fds[2]; struct vcpu_reg_state vrs; if ((vm = vm_getbyvmid(imsg->hdr.peerid)) == NULL) { log_warnx("%s: can't find vm", __func__); ret = ENOENT; goto err; } vcp = &vm->vm_params; if ((vm->vm_tty = imsg->fd) == -1) { log_warnx("%s: can't get tty", __func__); goto err; } if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, fds) == -1) fatal("socketpair"); /* Start child vmd for this VM (fork, chroot, drop privs) */ ret = start_client_vmd(); /* Start child failed? - cleanup and leave */ if (ret == -1) { log_warnx("%s: start child failed", __func__); ret = EIO; goto err; } if (ret > 0) { /* Parent */ vm->vm_pid = ret; for (i = 0 ; i < vcp->vcp_ndisks; i++) { close(vm->vm_disks[i]); vm->vm_disks[i] = -1; } for (i = 0 ; i < vcp->vcp_nnics; i++) { close(vm->vm_ifs[i]); vm->vm_ifs[i] = -1; } close(vm->vm_kernel); vm->vm_kernel = -1; close(vm->vm_tty); vm->vm_tty = -1; /* read back the kernel-generated vm id from the child */ close(fds[1]); if (read(fds[0], &vcp->vcp_id, sizeof(vcp->vcp_id)) != sizeof(vcp->vcp_id)) fatal("read vcp id"); close(fds[0]); if (vcp->vcp_id == 0) goto err; *id = vcp->vcp_id; return (0); } else { /* Child */ setproctitle("%s", vcp->vcp_name); log_procinit(vcp->vcp_name); create_memory_map(vcp); ret = alloc_guest_mem(vcp); if (ret) { errno = ret; fatal("could not allocate guest memory - exiting"); } ret = vmm_create_vm(vcp); current_vm = vm; /* send back the kernel-generated vm id (0 on error) */ close(fds[0]); if (write(fds[1], &vcp->vcp_id, sizeof(vcp->vcp_id)) != sizeof(vcp->vcp_id)) fatal("write vcp id"); close(fds[1]); if (ret) { errno = ret; fatal("create vmm ioctl failed - exiting"); } #if 0 /* * pledge in the vm processes: * stdio - for malloc and basic I/O including events. * vmm - for the vmm ioctls and operations. */ if (XXX("stdio vmm", NULL) == -1) fatal("pledge"); #endif /* * Set up default "flat 32 bit" register state - RIP, * RSP, and GDT info will be set in bootloader */ memcpy(&vrs, &vcpu_init_flat32, sizeof(struct vcpu_reg_state)); /* Load kernel image */ ret = loadelf_main(vm->vm_kernel, vcp, &vrs); if (ret) { errno = ret; fatal("failed to load kernel - exiting"); } close(vm->vm_kernel); con_fd = vm->vm_tty; if (fcntl(con_fd, F_SETFL, O_NONBLOCK) == -1) fatal("failed to set nonblocking mode on console"); /* Execute the vcpu run loop(s) for this VM */ ret = run_vm(vm->vm_disks, vm->vm_ifs, vcp, &vrs); _exit(ret != 0); } return (0); err: vm_remove(vm); return (ret); } /* * get_info_vm * * Returns a list of VMs known to vmm(4). * * Parameters: * ps: the privsep context. * imsg: the received imsg including the peer id. * terminate: terminate the listed vm. * * Return values: * 0: success * !0 : failure (eg, ENOMEM, EIO or another error code from vmm(4) ioctl) */ int get_info_vm(struct privsep *ps, struct imsg *imsg, int terminate) { int ret; size_t ct, i; struct vm_info_params vip; struct vm_info_result *info; struct vm_terminate_params vtp; struct vmop_info_result vir; /* * We issue the VMM_IOC_INFO ioctl twice, once with an input * buffer size of 0, which results in vmm(4) returning the * number of bytes required back to us in vip.vip_size, * and then we call it again after malloc'ing the required * number of bytes. * * It is possible that we could fail a second time (eg, if * another VM was created in the instant between the two * ioctls, but in that case the caller can just try again * as vmm(4) will return a zero-sized list in that case. */ vip.vip_size = 0; info = NULL; ret = 0; memset(&vir, 0, sizeof(vir)); /* First ioctl to see how many bytes needed (vip.vip_size) */ if (ioctl(env->vmd_fd, VMM_IOC_INFO, &vip) < 0) return (errno); if (vip.vip_info_ct != 0) return (EIO); info = malloc(vip.vip_size); if (info == NULL) return (ENOMEM); /* Second ioctl to get the actual list */ vip.vip_info = info; if (ioctl(env->vmd_fd, VMM_IOC_INFO, &vip) < 0) { ret = errno; free(info); return (ret); } /* Return info */ ct = vip.vip_size / sizeof(struct vm_info_result); for (i = 0; i < ct; i++) { if (terminate) { vtp.vtp_vm_id = info[i].vir_id; if ((ret = terminate_vm(&vtp)) != 0) return (ret); log_debug("%s: terminated VM %s (id %d)", __func__, info[i].vir_name, info[i].vir_id); continue; } memcpy(&vir.vir_info, &info[i], sizeof(vir.vir_info)); if (proc_compose_imsg(ps, PROC_PARENT, -1, IMSG_VMDOP_GET_INFO_VM_DATA, imsg->hdr.peerid, -1, &vir, sizeof(vir)) == -1) return (EIO); } free(info); return (0); } /* * start_client_vmd * * forks a copy of the parent vmd, chroots to VMD_USER's home, drops * privileges (changes to user VMD_USER), and returns. * Should the fork operation succeed, but later chroot/privsep * fail, the child exits. * * Return values (returns to both child and parent on success): * -1 : failure * 0: return to child vmd returns 0 * !0 : return to parent vmd returns the child's pid */ int start_client_vmd(void) { int child_pid; child_pid = fork(); if (child_pid < 0) return (-1); if (!child_pid) { /* child, already running without privileges */ return (0); } /* Parent */ return (child_pid); } /* * create_memory_map * * Sets up the guest physical memory ranges that the VM can access. * * Return values: * nothing */ void create_memory_map(struct vm_create_params *vcp) { size_t len, mem_bytes, mem_mb; mem_mb = vcp->vcp_memranges[0].vmr_size; vcp->vcp_nmemranges = 0; if (mem_mb < 1 || mem_mb > VMM_MAX_VM_MEM_SIZE) return; mem_bytes = mem_mb * 1024 * 1024; /* First memory region: 0 - LOWMEM_KB (DOS low mem) */ len = LOWMEM_KB * 1024; vcp->vcp_memranges[0].vmr_gpa = 0x0; vcp->vcp_memranges[0].vmr_size = len; mem_bytes -= len; /* * Second memory region: LOWMEM_KB - 1MB. * * N.B. - Normally ROMs or parts of video RAM are mapped here. * We have to add this region, because some systems * unconditionally write to 0xb8000 (VGA RAM), and * we need to make sure that vmm(4) permits accesses * to it. So allocate guest memory for it. */ len = 0x100000 - LOWMEM_KB * 1024; vcp->vcp_memranges[1].vmr_gpa = LOWMEM_KB * 1024; vcp->vcp_memranges[1].vmr_size = len; mem_bytes -= len; /* Make sure that we do not place physical memory into MMIO ranges. */ if (mem_bytes > VMM_PCI_MMIO_BAR_BASE - 0x100000) len = VMM_PCI_MMIO_BAR_BASE - 0x100000; else len = mem_bytes; /* Third memory region: 1MB - (1MB + len) */ vcp->vcp_memranges[2].vmr_gpa = 0x100000; vcp->vcp_memranges[2].vmr_size = len; mem_bytes -= len; if (mem_bytes > 0) { /* Fourth memory region for the remaining memory (if any) */ vcp->vcp_memranges[3].vmr_gpa = VMM_PCI_MMIO_BAR_END + 1; vcp->vcp_memranges[3].vmr_size = mem_bytes; vcp->vcp_nmemranges = 4; } else vcp->vcp_nmemranges = 3; } /* * alloc_guest_mem * * Allocates memory for the guest. * Instead of doing a single allocation with one mmap(), we allocate memory * separately for every range for the following reasons: * - ASLR for the individual ranges * - to reduce memory consumption in the UVM subsystem: if vmm(4) had to * map the single mmap'd userspace memory to the individual guest physical * memory ranges, the underlying amap of the single mmap'd range would have * to allocate per-page reference counters. The reason is that the * individual guest physical ranges would reference the single mmap'd region * only partially. However, if every guest physical range has its own * corresponding mmap'd userspace allocation, there are no partial * references: every guest physical range fully references an mmap'd * range => no per-page reference counters have to be allocated. * * Return values: * 0: success * !0: failure - errno indicating the source of the failure */ int alloc_guest_mem(struct vm_create_params *vcp) { void *p; int ret; size_t i, j; struct vm_mem_range *vmr; for (i = 0; i < vcp->vcp_nmemranges; i++) { vmr = &vcp->vcp_memranges[i]; p = mmap(NULL, vmr->vmr_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0); if (p == MAP_FAILED) { ret = errno; for (j = 0; j < i; j++) { vmr = &vcp->vcp_memranges[j]; munmap((void *)vmr->vmr_va, vmr->vmr_size); } return (ret); } vmr->vmr_va = (vaddr_t)p; } return (0); } /* * vmm_create_vm * * Requests vmm(4) to create a new VM using the supplied creation * parameters. This operation results in the creation of the in-kernel * structures for the VM, but does not start the VM's vcpu(s). * * Parameters: * vcp: vm_create_params struct containing the VM's desired creation * configuration * * Return values: * 0: success * !0 : ioctl to vmm(4) failed */ int vmm_create_vm(struct vm_create_params *vcp) { /* Sanity check arguments */ if (vcp->vcp_ncpus > VMM_MAX_VCPUS_PER_VM) return (EINVAL); if (vcp->vcp_nmemranges == 0 || vcp->vcp_nmemranges > VMM_MAX_MEM_RANGES) return (EINVAL); if (vcp->vcp_ndisks > VMM_MAX_DISKS_PER_VM) return (EINVAL); if (vcp->vcp_nnics > VMM_MAX_NICS_PER_VM) return (EINVAL); if (ioctl(env->vmd_fd, VMM_IOC_CREATE, vcp) < 0) return (errno); return (0); } /* * init_emulated_hw * * Initializes the userspace hardware emulation */ void init_emulated_hw(struct vm_create_params *vcp, int *child_disks, int *child_taps) { int i; /* Reset the IO port map */ memset(&ioports_map, 0, sizeof(io_fn_t) * MAX_PORTS); /* Init i8253 PIT */ i8253_init(vcp->vcp_id); ioports_map[TIMER_CTRL] = vcpu_exit_i8253; ioports_map[TIMER_BASE + TIMER_CNTR0] = vcpu_exit_i8253; ioports_map[TIMER_BASE + TIMER_CNTR1] = vcpu_exit_i8253; ioports_map[TIMER_BASE + TIMER_CNTR2] = vcpu_exit_i8253; /* Init mc146818 RTC */ mc146818_init(vcp->vcp_id); ioports_map[IO_RTC] = vcpu_exit_mc146818; ioports_map[IO_RTC + 1] = vcpu_exit_mc146818; /* Init master and slave PICs */ i8259_init(); ioports_map[IO_ICU1] = vcpu_exit_i8259; ioports_map[IO_ICU1 + 1] = vcpu_exit_i8259; ioports_map[IO_ICU2] = vcpu_exit_i8259; ioports_map[IO_ICU2 + 1] = vcpu_exit_i8259; /* Init ns8250 UART */ ns8250_init(con_fd, vcp->vcp_id); for (i = COM1_DATA; i <= COM1_SCR; i++) ioports_map[i] = vcpu_exit_com; /* Initialize PCI */ for (i = VMM_PCI_IO_BAR_BASE; i <= VMM_PCI_IO_BAR_END; i++) ioports_map[i] = vcpu_exit_pci; ioports_map[PCI_MODE1_ADDRESS_REG] = vcpu_exit_pci; ioports_map[PCI_MODE1_DATA_REG] = vcpu_exit_pci; pci_init(); /* Initialize virtio devices */ virtio_init(vcp, child_disks, child_taps); } /* * run_vm * * Runs the VM whose creation parameters are specified in vcp * * Parameters: * child_disks: previously-opened child VM disk file file descriptors * child_taps: previously-opened child tap file descriptors * vcp: vm_create_params struct containing the VM's desired creation * configuration * vrs: VCPU register state to initialize * * Return values: * 0: the VM exited normally * !0 : the VM exited abnormally or failed to start */ int run_vm(int *child_disks, int *child_taps, struct vm_create_params *vcp, struct vcpu_reg_state *vrs) { uint8_t evdone = 0; size_t i; int ret; pthread_t *tid, evtid; struct vm_run_params **vrp; void *exit_status; if (vcp == NULL) return (EINVAL); if (child_disks == NULL && vcp->vcp_ndisks != 0) return (EINVAL); if (child_taps == NULL && vcp->vcp_nnics != 0) return (EINVAL); if (vcp->vcp_ncpus > VMM_MAX_VCPUS_PER_VM) return (EINVAL); if (vcp->vcp_ndisks > VMM_MAX_DISKS_PER_VM) return (EINVAL); if (vcp->vcp_nnics > VMM_MAX_NICS_PER_VM) return (EINVAL); if (vcp->vcp_nmemranges == 0 || vcp->vcp_nmemranges > VMM_MAX_MEM_RANGES) return (EINVAL); event_init(); tid = calloc(vcp->vcp_ncpus, sizeof(pthread_t)); vrp = calloc(vcp->vcp_ncpus, sizeof(struct vm_run_params *)); if (tid == NULL || vrp == NULL) { log_warn("%s: memory allocation error - exiting.", __progname); return (ENOMEM); } log_debug("%s: initializing hardware for vm %s", __func__, vcp->vcp_name); init_emulated_hw(vcp, child_disks, child_taps); ret = pthread_mutex_init(&threadmutex, NULL); if (ret) { log_warn("%s: could not initialize thread state mutex", __func__); return (ret); } ret = pthread_cond_init(&threadcond, NULL); if (ret) { log_warn("%s: could not initialize thread state " "condition variable", __func__); return (ret); } mutex_lock(&threadmutex); log_debug("%s: starting vcpu threads for vm %s", __func__, vcp->vcp_name); /* * Create and launch one thread for each VCPU. These threads may * migrate between PCPUs over time; the need to reload CPU state * in such situations is detected and performed by vmm(4) in the * kernel. */ for (i = 0 ; i < vcp->vcp_ncpus; i++) { vrp[i] = malloc(sizeof(struct vm_run_params)); if (vrp[i] == NULL) { log_warn("%s: memory allocation error - " "exiting.", __progname); /* caller will exit, so skip free'ing */ return (ENOMEM); } vrp[i]->vrp_exit = malloc(sizeof(union vm_exit)); if (vrp[i]->vrp_exit == NULL) { log_warn("%s: memory allocation error - " "exiting.", __progname); /* caller will exit, so skip free'ing */ return (ENOMEM); } vrp[i]->vrp_vm_id = vcp->vcp_id; vrp[i]->vrp_vcpu_id = i; if (vcpu_reset(vcp->vcp_id, i, vrs)) { log_warnx("%s: cannot reset VCPU %zu - exiting.", __progname, i); return (EIO); } ret = pthread_cond_init(&vcpu_run_cond[i], NULL); if (ret) { log_warnx("%s: cannot initialize cond var (%d)", __progname, ret); return (ret); } ret = pthread_mutex_init(&vcpu_run_mtx[i], NULL); if (ret) { log_warnx("%s: cannot initialize mtx (%d)", __progname, ret); return (ret); } vcpu_hlt[i] = 0; /* Start each VCPU run thread at vcpu_run_loop */ ret = pthread_create(&tid[i], NULL, vcpu_run_loop, vrp[i]); if (ret) { /* caller will _exit after this return */ ret = errno; log_warn("%s: could not create vcpu thread %zu", __func__, i); return (ret); } } log_debug("%s: waiting on events for VM %s", __func__, vcp->vcp_name); ret = pthread_create(&evtid, NULL, event_thread, &evdone); if (ret) { errno = ret; log_warn("%s: could not create event thread", __func__); return (ret); } for (;;) { ret = pthread_cond_wait(&threadcond, &threadmutex); if (ret) { log_warn("%s: waiting on thread state condition " "variable failed", __func__); return (ret); } /* * Did a VCPU thread exit with an error? => return the first one */ for (i = 0; i < vcp->vcp_ncpus; i++) { if (vcpu_done[i] == 0) continue; if (pthread_join(tid[i], &exit_status)) { log_warn("%s: failed to join thread %zd - " "exiting", __progname, i); return (EIO); } if (exit_status != NULL) { log_warnx("%s: vm %d vcpu run thread %zd " "exited abnormally", __progname, vcp->vcp_id, i); return (EIO); } } /* Did the event thread exit? => return with an error */ if (evdone) { if (pthread_join(evtid, &exit_status)) { log_warn("%s: failed to join event thread - " "exiting", __progname); return (EIO); } log_warnx("%s: vm %d event thread exited " "unexpectedly", __progname, vcp->vcp_id); return (EIO); } /* Did all VCPU threads exit successfully? => return 0 */ for (i = 0; i < vcp->vcp_ncpus; i++) { if (vcpu_done[i] == 0) break; } if (i == vcp->vcp_ncpus) return (0); /* Some more threads to wait for, start over */ } return (0); } void * event_thread(void *arg) { uint8_t *donep = arg; intptr_t ret; ret = event_dispatch(); mutex_lock(&threadmutex); *donep = 1; pthread_cond_signal(&threadcond); mutex_unlock(&threadmutex); return (void *)ret; } /* * vcpu_run_loop * * Runs a single VCPU until vmm(4) requires help handling an exit, * or the VM terminates. * * Parameters: * arg: vcpu_run_params for the VCPU being run by this thread * * Return values: * NULL: the VCPU shutdown properly * !NULL: error processing VCPU run, or the VCPU shutdown abnormally */ void * vcpu_run_loop(void *arg) { struct vm_run_params *vrp = (struct vm_run_params *)arg; intptr_t ret = 0; int irq; uint32_t n; vrp->vrp_continue = 0; n = vrp->vrp_vcpu_id; for (;;) { ret = pthread_mutex_lock(&vcpu_run_mtx[n]); if (ret) { log_warnx("%s: can't lock vcpu run mtx (%d)", __func__, (int)ret); return ((void *)ret); } /* If we are halted, wait */ if (vcpu_hlt[n]) { ret = pthread_cond_wait(&vcpu_run_cond[n], &vcpu_run_mtx[n]); if (ret) { log_warnx("%s: can't wait on cond (%d)", __func__, (int)ret); (void)pthread_mutex_unlock(&vcpu_run_mtx[n]); break; } } ret = pthread_mutex_unlock(&vcpu_run_mtx[n]); if (ret) { log_warnx("%s: can't unlock mutex on cond (%d)", __func__, (int)ret); break; } if (vrp->vrp_irqready && i8259_is_pending()) { irq = i8259_ack(); vrp->vrp_irq = irq; } else vrp->vrp_irq = 0xFFFF; /* Still more pending? */ if (i8259_is_pending()) { /* XXX can probably avoid ioctls here by providing intr in vrp */ if (vcpu_pic_intr(vrp->vrp_vm_id, vrp->vrp_vcpu_id, 1)) { fatal("can't set INTR"); } } else { if (vcpu_pic_intr(vrp->vrp_vm_id, vrp->vrp_vcpu_id, 0)) { fatal("can't clear INTR"); } } if (ioctl(env->vmd_fd, VMM_IOC_RUN, vrp) < 0) { /* If run ioctl failed, exit */ ret = errno; log_warn("%s: vm %d / vcpu %d run ioctl failed", __func__, vrp->vrp_vm_id, n); break; } /* If the VM is terminating, exit normally */ if (vrp->vrp_exit_reason == VM_EXIT_TERMINATED) { ret = (intptr_t)NULL; break; } if (vrp->vrp_exit_reason != VM_EXIT_NONE) { /* * vmm(4) needs help handling an exit, handle in * vcpu_exit. */ if (vcpu_exit(vrp)) { ret = EIO; break; } } } mutex_lock(&threadmutex); vcpu_done[n] = 1; pthread_cond_signal(&threadcond); mutex_unlock(&threadmutex); return ((void *)ret); } int vcpu_pic_intr(uint32_t vm_id, uint32_t vcpu_id, uint8_t intr) { struct vm_intr_params vip; memset(&vip, 0, sizeof(vip)); vip.vip_vm_id = vm_id; vip.vip_vcpu_id = vcpu_id; /* XXX always 0? */ vip.vip_intr = intr; if (ioctl(env->vmd_fd, VMM_IOC_INTR, &vip) < 0) return (errno); return (0); } /* * vcpu_exit_pci * * Handle all I/O to the emulated PCI subsystem. * * Parameters: * vrp: vcpu run paramters containing guest state for this exit * * Return value: * Interrupt to inject to the guest VM, or 0xFF if no interrupt should * be injected. */ uint8_t vcpu_exit_pci(struct vm_run_params *vrp) { union vm_exit *vei = vrp->vrp_exit; uint8_t intr; intr = 0xFF; switch (vei->vei.vei_port) { case PCI_MODE1_ADDRESS_REG: pci_handle_address_reg(vrp); break; case PCI_MODE1_DATA_REG: pci_handle_data_reg(vrp); break; case VMM_PCI_IO_BAR_BASE ... VMM_PCI_IO_BAR_END: intr = pci_handle_io(vrp); break; default: log_warnx("%s: unknown PCI register 0x%llx", __progname, (uint64_t)vei->vei.vei_port); break; } return (intr); } /* * vcpu_exit_inout * * Handle all I/O exits that need to be emulated in vmd. This includes the * i8253 PIT, the com1 ns8250 UART, and the MC146818 RTC/NVRAM device. * * Parameters: * vrp: vcpu run parameters containing guest state for this exit */ void vcpu_exit_inout(struct vm_run_params *vrp) { union vm_exit *vei = vrp->vrp_exit; uint8_t intr = 0xFF; if (ioports_map[vei->vei.vei_port] != NULL) intr = ioports_map[vei->vei.vei_port](vrp); else if (vei->vei.vei_dir == VEI_DIR_IN) vei->vei.vei_data = 0xFFFFFFFF; if (intr != 0xFF) vcpu_assert_pic_irq(vrp->vrp_vm_id, vrp->vrp_vcpu_id, intr); } /* * vcpu_exit * * Handle a vcpu exit. This function is called when it is determined that * vmm(4) requires the assistance of vmd to support a particular guest * exit type (eg, accessing an I/O port or device). Guest state is contained * in 'vrp', and will be resent to vmm(4) on exit completion. * * Upon conclusion of handling the exit, the function determines if any * interrupts should be injected into the guest, and asserts the proper * IRQ line whose interrupt should be vectored. * * Parameters: * vrp: vcpu run parameters containing guest state for this exit * * Return values: * 0: the exit was handled successfully * 1: an error occurred (eg, unknown exit reason passed in 'vrp') */ int vcpu_exit(struct vm_run_params *vrp) { int ret; switch (vrp->vrp_exit_reason) { case VMX_EXIT_IO: vcpu_exit_inout(vrp); break; case VMX_EXIT_HLT: ret = pthread_mutex_lock(&vcpu_run_mtx[vrp->vrp_vcpu_id]); if (ret) { log_warnx("%s: can't lock vcpu mutex (%d)", __func__, ret); return (1); } vcpu_hlt[vrp->vrp_vcpu_id] = 1; ret = pthread_mutex_unlock(&vcpu_run_mtx[vrp->vrp_vcpu_id]); if (ret) { log_warnx("%s: can't unlock vcpu mutex (%d)", __func__, ret); return (1); } break; case VMX_EXIT_INT_WINDOW: break; case VMX_EXIT_TRIPLE_FAULT: log_warnx("%s: triple fault", __progname); return (1); default: log_debug("%s: unknown exit reason %d", __progname, vrp->vrp_exit_reason); } /* XXX this may not be irq 9 all the time */ if (vionet_process_rx()) vcpu_assert_pic_irq(vrp->vrp_vm_id, vrp->vrp_vcpu_id, 9); vrp->vrp_continue = 1; return (0); } /* * find_gpa_range * * Search for a contiguous guest physical mem range. * * Parameters: * vcp: VM create parameters that contain the memory map to search in * gpa: the starting guest physical address * len: the length of the memory range * * Return values: * NULL: on failure if there is no memory range as described by the parameters * Pointer to vm_mem_range that contains the start of the range otherwise. */ static struct vm_mem_range * find_gpa_range(struct vm_create_params *vcp, paddr_t gpa, size_t len) { size_t i, n; struct vm_mem_range *vmr; /* Find the first vm_mem_range that contains gpa */ for (i = 0; i < vcp->vcp_nmemranges; i++) { vmr = &vcp->vcp_memranges[i]; if (vmr->vmr_gpa + vmr->vmr_size >= gpa) break; } /* No range found. */ if (i == vcp->vcp_nmemranges) return (NULL); /* * vmr may cover the range [gpa, gpa + len) only partly. Make * sure that the following vm_mem_ranges are contiguous and * cover the rest. */ n = vmr->vmr_size - (gpa - vmr->vmr_gpa); if (len < n) len = 0; else len -= n; gpa = vmr->vmr_gpa + vmr->vmr_size; for (i = i + 1; len != 0 && i < vcp->vcp_nmemranges; i++) { vmr = &vcp->vcp_memranges[i]; if (gpa != vmr->vmr_gpa) return (NULL); if (len <= vmr->vmr_size) len = 0; else len -= vmr->vmr_size; gpa = vmr->vmr_gpa + vmr->vmr_size; } if (len != 0) return (NULL); return (vmr); } /* * write_mem * * Copies data from 'buf' into the guest VM's memory at paddr 'dst'. * * Parameters: * dst: the destination paddr_t in the guest VM * buf: data to copy * len: number of bytes to copy * * Return values: * 0: success * EINVAL: if the guest physical memory range [dst, dst + len) does not * exist in the guest. */ int write_mem(paddr_t dst, void *buf, size_t len) { char *from = buf, *to; size_t n, off; struct vm_mem_range *vmr; vmr = find_gpa_range(¤t_vm->vm_params, dst, len); if (vmr == NULL) { errno = EINVAL; log_warn("%s: failed - invalid memory range dst = 0x%lx, " "len = 0x%zx", __func__, dst, len); return (EINVAL); } off = dst - vmr->vmr_gpa; while (len != 0) { n = vmr->vmr_size - off; if (len < n) n = len; to = (char *)vmr->vmr_va + off; memcpy(to, from, n); from += n; len -= n; off = 0; vmr++; } return (0); } /* * read_mem * * Reads memory at guest paddr 'src' into 'buf'. * * Parameters: * src: the source paddr_t in the guest VM to read from. * buf: destination (local) buffer * len: number of bytes to read * * Return values: * 0: success * EINVAL: if the guest physical memory range [dst, dst + len) does not * exist in the guest. */ int read_mem(paddr_t src, void *buf, size_t len) { char *from, *to = buf; size_t n, off; struct vm_mem_range *vmr; vmr = find_gpa_range(¤t_vm->vm_params, src, len); if (vmr == NULL) { errno = EINVAL; log_warn("%s: failed - invalid memory range src = 0x%lx, " "len = 0x%zx", __func__, src, len); return (EINVAL); } off = src - vmr->vmr_gpa; while (len != 0) { n = vmr->vmr_size - off; if (len < n) n = len; from = (char *)vmr->vmr_va + off; memcpy(to, from, n); to += n; len -= n; off = 0; vmr++; } return (0); } /* * vcpu_assert_pic_irq * * Injects the specified IRQ on the supplied vcpu/vm * * Parameters: * vm_id: VM ID to inject to * vcpu_id: VCPU ID to inject to * irq: IRQ to inject */ void vcpu_assert_pic_irq(uint32_t vm_id, uint32_t vcpu_id, int irq) { int ret; i8259_assert_irq(irq); if (i8259_is_pending()) { if (vcpu_pic_intr(vm_id, vcpu_id, 1)) fatalx("%s: can't assert INTR", __func__); ret = pthread_mutex_lock(&vcpu_run_mtx[vcpu_id]); if (ret) fatalx("%s: can't lock vcpu mtx (%d)", __func__, ret); vcpu_hlt[vcpu_id] = 0; ret = pthread_cond_signal(&vcpu_run_cond[vcpu_id]); if (ret) fatalx("%s: can't signal (%d)", __func__, ret); ret = pthread_mutex_unlock(&vcpu_run_mtx[vcpu_id]); if (ret) fatalx("%s: can't unlock vcpu mtx (%d)", __func__, ret); } } /* * fd_hasdata * * Determines if data can be read from a file descriptor. * * Parameters: * fd: the fd to check * * Return values: * 1 if data can be read from an fd, or 0 otherwise. */ int fd_hasdata(int fd) { struct pollfd pfd[1]; int nready, hasdata = 0; pfd[0].fd = fd; pfd[0].events = POLLIN; nready = poll(pfd, 1, 0); if (nready == -1) log_warn("checking file descriptor for data failed"); else if (nready == 1 && pfd[0].revents & POLLIN) hasdata = 1; return (hasdata); } /* * mutex_lock * * Wrapper function for pthread_mutex_lock that does error checking and that * exits on failure */ void mutex_lock(pthread_mutex_t *m) { int ret; ret = pthread_mutex_lock(m); if (ret) { errno = ret; fatal("could not acquire mutex"); } } /* * mutex_unlock * * Wrapper function for pthread_mutex_unlock that does error checking and that * exits on failure */ void mutex_unlock(pthread_mutex_t *m) { int ret; ret = pthread_mutex_unlock(m); if (ret) { errno = ret; fatal("could not release mutex"); } }