diff options
Diffstat (limited to 'usr/src/cmd/bhyve/inout.c')
-rw-r--r-- | usr/src/cmd/bhyve/inout.c | 299 |
1 files changed, 299 insertions, 0 deletions
diff --git a/usr/src/cmd/bhyve/inout.c b/usr/src/cmd/bhyve/inout.c new file mode 100644 index 0000000000..b460ee2988 --- /dev/null +++ b/usr/src/cmd/bhyve/inout.c @@ -0,0 +1,299 @@ +/*- + * SPDX-License-Identifier: BSD-2-Clause-FreeBSD + * + * Copyright (c) 2011 NetApp, Inc. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * $FreeBSD$ + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/param.h> +#include <sys/linker_set.h> +#include <sys/_iovec.h> +#include <sys/mman.h> + +#include <x86/psl.h> +#include <x86/segments.h> + +#include <machine/vmm.h> +#include <machine/vmm_instruction_emul.h> +#include <vmmapi.h> + +#include <stdio.h> +#include <string.h> +#include <assert.h> + +#include "bhyverun.h" +#include "inout.h" + +SET_DECLARE(inout_port_set, struct inout_port); + +#define MAX_IOPORTS (1 << 16) + +#define VERIFY_IOPORT(port, size) \ + assert((port) >= 0 && (size) > 0 && ((port) + (size)) <= MAX_IOPORTS) + +static struct { + const char *name; + int flags; + inout_func_t handler; + void *arg; +} inout_handlers[MAX_IOPORTS]; + +static int +default_inout(struct vmctx *ctx, int vcpu, int in, int port, int bytes, + uint32_t *eax, void *arg) +{ + if (in) { + switch (bytes) { + case 4: + *eax = 0xffffffff; + break; + case 2: + *eax = 0xffff; + break; + case 1: + *eax = 0xff; + break; + } + } + + return (0); +} + +static void +register_default_iohandler(int start, int size) +{ + struct inout_port iop; + + VERIFY_IOPORT(start, size); + + bzero(&iop, sizeof(iop)); + iop.name = "default"; + iop.port = start; + iop.size = size; + iop.flags = IOPORT_F_INOUT | IOPORT_F_DEFAULT; + iop.handler = default_inout; + + register_inout(&iop); +} + +int +emulate_inout(struct vmctx *ctx, int vcpu, struct vm_exit *vmexit, int strict) +{ + int addrsize, bytes, flags, in, port, prot, rep; + uint32_t eax, val; + inout_func_t handler; + void *arg; + int error, fault, retval; + enum vm_reg_name idxreg; + uint64_t gla, index, iterations, count; + struct vm_inout_str *vis; + struct iovec iov[2]; + + bytes = vmexit->u.inout.bytes; + in = vmexit->u.inout.in; + port = vmexit->u.inout.port; + + assert(port < MAX_IOPORTS); + assert(bytes == 1 || bytes == 2 || bytes == 4); + + handler = inout_handlers[port].handler; + + if (strict && handler == default_inout) + return (-1); + + flags = inout_handlers[port].flags; + arg = inout_handlers[port].arg; + + if (in) { + if (!(flags & IOPORT_F_IN)) + return (-1); + } else { + if (!(flags & IOPORT_F_OUT)) + return (-1); + } + + retval = 0; + if (vmexit->u.inout.string) { + vis = &vmexit->u.inout_str; + rep = vis->inout.rep; + addrsize = vis->addrsize; + prot = in ? PROT_WRITE : PROT_READ; + assert(addrsize == 2 || addrsize == 4 || addrsize == 8); + + /* Index register */ + idxreg = in ? VM_REG_GUEST_RDI : VM_REG_GUEST_RSI; + index = vis->index & vie_size2mask(addrsize); + + /* Count register */ + count = vis->count & vie_size2mask(addrsize); + + /* Limit number of back-to-back in/out emulations to 16 */ + iterations = MIN(count, 16); + while (iterations > 0) { + assert(retval == 0); + if (vie_calculate_gla(vis->paging.cpu_mode, + vis->seg_name, &vis->seg_desc, index, bytes, + addrsize, prot, &gla)) { + vm_inject_gp(ctx, vcpu); + break; + } + + error = vm_copy_setup(ctx, vcpu, &vis->paging, gla, + bytes, prot, iov, nitems(iov), &fault); + if (error) { + retval = -1; /* Unrecoverable error */ + break; + } else if (fault) { + retval = 0; /* Resume guest to handle fault */ + break; + } + + if (vie_alignment_check(vis->paging.cpl, bytes, + vis->cr0, vis->rflags, gla)) { + vm_inject_ac(ctx, vcpu, 0); + break; + } + + val = 0; + if (!in) + vm_copyin(ctx, vcpu, iov, &val, bytes); + + retval = handler(ctx, vcpu, in, port, bytes, &val, arg); + if (retval != 0) + break; + + if (in) + vm_copyout(ctx, vcpu, &val, iov, bytes); + + /* Update index */ + if (vis->rflags & PSL_D) + index -= bytes; + else + index += bytes; + + count--; + iterations--; + } + + /* Update index register */ + error = vie_update_register(ctx, vcpu, idxreg, index, addrsize); + assert(error == 0); + + /* + * Update count register only if the instruction had a repeat + * prefix. + */ + if (rep) { + error = vie_update_register(ctx, vcpu, VM_REG_GUEST_RCX, + count, addrsize); + assert(error == 0); + } + + /* Restart the instruction if more iterations remain */ + if (retval == 0 && count != 0) { + error = vm_restart_instruction(ctx, vcpu); + assert(error == 0); + } + } else { + eax = vmexit->u.inout.eax; + val = eax & vie_size2mask(bytes); + retval = handler(ctx, vcpu, in, port, bytes, &val, arg); + if (retval == 0 && in) { + eax &= ~vie_size2mask(bytes); + eax |= val & vie_size2mask(bytes); + error = vm_set_register(ctx, vcpu, VM_REG_GUEST_RAX, + eax); + assert(error == 0); + } + } + return (retval); +} + +void +init_inout(void) +{ + struct inout_port **iopp, *iop; + + /* + * Set up the default handler for all ports + */ + register_default_iohandler(0, MAX_IOPORTS); + + /* + * Overwrite with specified handlers + */ + SET_FOREACH(iopp, inout_port_set) { + iop = *iopp; + assert(iop->port < MAX_IOPORTS); + inout_handlers[iop->port].name = iop->name; + inout_handlers[iop->port].flags = iop->flags; + inout_handlers[iop->port].handler = iop->handler; + inout_handlers[iop->port].arg = NULL; + } +} + +int +register_inout(struct inout_port *iop) +{ + int i; + + VERIFY_IOPORT(iop->port, iop->size); + + /* + * Verify that the new registration is not overwriting an already + * allocated i/o range. + */ + if ((iop->flags & IOPORT_F_DEFAULT) == 0) { + for (i = iop->port; i < iop->port + iop->size; i++) { + if ((inout_handlers[i].flags & IOPORT_F_DEFAULT) == 0) + return (-1); + } + } + + for (i = iop->port; i < iop->port + iop->size; i++) { + inout_handlers[i].name = iop->name; + inout_handlers[i].flags = iop->flags; + inout_handlers[i].handler = iop->handler; + inout_handlers[i].arg = iop->arg; + } + + return (0); +} + +int +unregister_inout(struct inout_port *iop) +{ + + VERIFY_IOPORT(iop->port, iop->size); + assert(inout_handlers[iop->port].name == iop->name); + + register_default_iohandler(iop->port, iop->size); + + return (0); +} |