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Diffstat (limited to 'usr.sbin/bhyve/mem.c')
| -rw-r--r-- | usr.sbin/bhyve/mem.c | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/usr.sbin/bhyve/mem.c b/usr.sbin/bhyve/mem.c new file mode 100644 index 0000000..27f4782 --- /dev/null +++ b/usr.sbin/bhyve/mem.c @@ -0,0 +1,218 @@ +/*- + * Copyright (c) 2012 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. + * + * $FreeBSD$ + */ + +/* + * Memory ranges are represented with an RB tree. On insertion, the range + * is checked for overlaps. On lookup, the key has the same base and limit + * so it can be searched within the range. + * + * It is assumed that all setup of ranges takes place in single-threaded + * mode before vCPUs have been started. As such, no locks are used on the + * RB tree. If this is no longer the case, then a r/w lock could be used, + * with readers on the lookup and a writer if the tree needs to be changed + * (and per vCPU caches flushed) + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/types.h> +#include <sys/tree.h> +#include <sys/errno.h> +#include <machine/vmm.h> + +#include <stdio.h> +#include <stdlib.h> +#include <assert.h> + +#include "mem.h" + +struct mmio_rb_range { + RB_ENTRY(mmio_rb_range) mr_link; /* RB tree links */ + struct mem_range mr_param; + uint64_t mr_base; + uint64_t mr_end; +}; + +struct mmio_rb_tree; +RB_PROTOTYPE(mmio_rb_tree, mmio_rb_range, mr_link, mmio_rb_range_compare); + +RB_HEAD(mmio_rb_tree, mmio_rb_range) mmio_rbroot; + +/* + * Per-vCPU cache. Since most accesses from a vCPU will be to + * consecutive addresses in a range, it makes sense to cache the + * result of a lookup. + */ +static struct mmio_rb_range *mmio_hint[VM_MAXCPU]; + +static int +mmio_rb_range_compare(struct mmio_rb_range *a, struct mmio_rb_range *b) +{ + if (a->mr_end < b->mr_base) + return (-1); + else if (a->mr_base > b->mr_end) + return (1); + return (0); +} + +static int +mmio_rb_lookup(uint64_t addr, struct mmio_rb_range **entry) +{ + struct mmio_rb_range find, *res; + + find.mr_base = find.mr_end = addr; + + res = RB_FIND(mmio_rb_tree, &mmio_rbroot, &find); + + if (res != NULL) { + *entry = res; + return (0); + } + + return (ENOENT); +} + +static int +mmio_rb_add(struct mmio_rb_range *new) +{ + struct mmio_rb_range *overlap; + + overlap = RB_INSERT(mmio_rb_tree, &mmio_rbroot, new); + + if (overlap != NULL) { +#ifdef RB_DEBUG + printf("overlap detected: new %lx:%lx, tree %lx:%lx\n", + new->mr_base, new->mr_end, + overlap->mr_base, overlap->mr_end); +#endif + + return (EEXIST); + } + + return (0); +} + +#if 0 +static void +mmio_rb_dump(void) +{ + struct mmio_rb_range *np; + + RB_FOREACH(np, mmio_rb_tree, &mmio_rbroot) { + printf(" %lx:%lx, %s\n", np->mr_base, np->mr_end, + np->mr_param.name); + } +} +#endif + +RB_GENERATE(mmio_rb_tree, mmio_rb_range, mr_link, mmio_rb_range_compare); + +static int +mem_read(void *ctx, int vcpu, uint64_t gpa, uint64_t *rval, int size, void *arg) +{ + int error; + struct mem_range *mr = arg; + + error = (*mr->handler)(ctx, vcpu, MEM_F_READ, gpa, size, + rval, mr->arg1, mr->arg2); + return (error); +} + +static int +mem_write(void *ctx, int vcpu, uint64_t gpa, uint64_t wval, int size, void *arg) +{ + int error; + struct mem_range *mr = arg; + + error = (*mr->handler)(ctx, vcpu, MEM_F_WRITE, gpa, size, + &wval, mr->arg1, mr->arg2); + return (error); +} + +int +emulate_mem(struct vmctx *ctx, int vcpu, uint64_t paddr, struct vie *vie) +{ + struct mmio_rb_range *entry; + int err; + + /* + * First check the per-vCPU cache + */ + if (mmio_hint[vcpu] && + paddr >= mmio_hint[vcpu]->mr_base && + paddr <= mmio_hint[vcpu]->mr_end) { + entry = mmio_hint[vcpu]; + } else + entry = NULL; + + if (entry == NULL) { + if (mmio_rb_lookup(paddr, &entry)) + return (ESRCH); + + /* Update the per-vCPU cache */ + mmio_hint[vcpu] = entry; + } + + assert(entry != NULL && entry == mmio_hint[vcpu]); + + err = vmm_emulate_instruction(ctx, vcpu, paddr, vie, + mem_read, mem_write, &entry->mr_param); + return (err); +} + +int +register_mem(struct mem_range *memp) +{ + struct mmio_rb_range *mrp; + int err; + + err = 0; + + mrp = malloc(sizeof(struct mmio_rb_range)); + + if (mrp != NULL) { + mrp->mr_param = *memp; + mrp->mr_base = memp->base; + mrp->mr_end = memp->base + memp->size - 1; + + err = mmio_rb_add(mrp); + if (err) + free(mrp); + } else + err = ENOMEM; + + return (err); +} + +void +init_mem(void) +{ + + RB_INIT(&mmio_rbroot); +} |
