1 /*- 2 * Copyright (c) 2012 NetApp, Inc. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD$ 27 */ 28 29 /* 30 * Memory ranges are represented with an RB tree. On insertion, the range 31 * is checked for overlaps. On lookup, the key has the same base and limit 32 * so it can be searched within the range. 33 * 34 * It is assumed that all setup of ranges takes place in single-threaded 35 * mode before vCPUs have been started. As such, no locks are used on the 36 * RB tree. If this is no longer the case, then a r/w lock could be used, 37 * with readers on the lookup and a writer if the tree needs to be changed 38 * (and per vCPU caches flushed) 39 */ 40 41 #include <sys/cdefs.h> 42 __FBSDID("$FreeBSD$"); 43 44 #include <sys/types.h> 45 #include <sys/tree.h> 46 #include <sys/errno.h> 47 #include <machine/vmm.h> 48 49 #include <stdio.h> 50 #include <stdlib.h> 51 #include <assert.h> 52 53 #include "mem.h" 54 55 struct mmio_rb_range { 56 RB_ENTRY(mmio_rb_range) mr_link; /* RB tree links */ 57 struct mem_range mr_param; 58 uint64_t mr_base; 59 uint64_t mr_end; 60 }; 61 62 struct mmio_rb_tree; 63 RB_PROTOTYPE(mmio_rb_tree, mmio_rb_range, mr_link, mmio_rb_range_compare); 64 65 RB_HEAD(mmio_rb_tree, mmio_rb_range) mmio_rbroot; 66 67 /* 68 * Per-vCPU cache. Since most accesses from a vCPU will be to 69 * consecutive addresses in a range, it makes sense to cache the 70 * result of a lookup. 71 */ 72 static struct mmio_rb_range *mmio_hint[VM_MAXCPU]; 73 74 static int 75 mmio_rb_range_compare(struct mmio_rb_range *a, struct mmio_rb_range *b) 76 { 77 if (a->mr_end < b->mr_base) 78 return (-1); 79 else if (a->mr_base > b->mr_end) 80 return (1); 81 return (0); 82 } 83 84 static int 85 mmio_rb_lookup(uint64_t addr, struct mmio_rb_range **entry) 86 { 87 struct mmio_rb_range find, *res; 88 89 find.mr_base = find.mr_end = addr; 90 91 res = RB_FIND(mmio_rb_tree, &mmio_rbroot, &find); 92 93 if (res != NULL) { 94 *entry = res; 95 return (0); 96 } 97 98 return (ENOENT); 99 } 100 101 static int 102 mmio_rb_add(struct mmio_rb_range *new) 103 { 104 struct mmio_rb_range *overlap; 105 106 overlap = RB_INSERT(mmio_rb_tree, &mmio_rbroot, new); 107 108 if (overlap != NULL) { 109 #ifdef RB_DEBUG 110 printf("overlap detected: new %lx:%lx, tree %lx:%lx\n", 111 new->mr_base, new->mr_end, 112 overlap->mr_base, overlap->mr_end); 113 #endif 114 115 return (EEXIST); 116 } 117 118 return (0); 119 } 120 121 #if 0 122 static void 123 mmio_rb_dump(void) 124 { 125 struct mmio_rb_range *np; 126 127 RB_FOREACH(np, mmio_rb_tree, &mmio_rbroot) { 128 printf(" %lx:%lx, %s\n", np->mr_base, np->mr_end, 129 np->mr_param.name); 130 } 131 } 132 #endif 133 134 RB_GENERATE(mmio_rb_tree, mmio_rb_range, mr_link, mmio_rb_range_compare); 135 136 static int 137 mem_read(void *ctx, int vcpu, uint64_t gpa, uint64_t *rval, int size, void *arg) 138 { 139 int error; 140 struct mem_range *mr = arg; 141 142 error = (*mr->handler)(ctx, vcpu, MEM_F_READ, gpa, size, 143 rval, mr->arg1, mr->arg2); 144 return (error); 145 } 146 147 static int 148 mem_write(void *ctx, int vcpu, uint64_t gpa, uint64_t wval, int size, void *arg) 149 { 150 int error; 151 struct mem_range *mr = arg; 152 153 error = (*mr->handler)(ctx, vcpu, MEM_F_WRITE, gpa, size, 154 &wval, mr->arg1, mr->arg2); 155 return (error); 156 } 157 158 int 159 emulate_mem(struct vmctx *ctx, int vcpu, uint64_t paddr, struct vie *vie) 160 { 161 struct mmio_rb_range *entry; 162 int err; 163 164 /* 165 * First check the per-vCPU cache 166 */ 167 if (mmio_hint[vcpu] && 168 paddr >= mmio_hint[vcpu]->mr_base && 169 paddr <= mmio_hint[vcpu]->mr_end) { 170 entry = mmio_hint[vcpu]; 171 } else 172 entry = NULL; 173 174 if (entry == NULL) { 175 if (mmio_rb_lookup(paddr, &entry)) 176 return (ESRCH); 177 178 /* Update the per-vCPU cache */ 179 mmio_hint[vcpu] = entry; 180 } 181 182 assert(entry != NULL && entry == mmio_hint[vcpu]); 183 184 err = vmm_emulate_instruction(ctx, vcpu, paddr, vie, 185 mem_read, mem_write, &entry->mr_param); 186 return (err); 187 } 188 189 int 190 register_mem(struct mem_range *memp) 191 { 192 struct mmio_rb_range *mrp; 193 int err; 194 195 err = 0; 196 197 mrp = malloc(sizeof(struct mmio_rb_range)); 198 199 if (mrp != NULL) { 200 mrp->mr_param = *memp; 201 mrp->mr_base = memp->base; 202 mrp->mr_end = memp->base + memp->size - 1; 203 204 err = mmio_rb_add(mrp); 205 if (err) 206 free(mrp); 207 } else 208 err = ENOMEM; 209 210 return (err); 211 } 212 213 void 214 init_mem(void) 215 { 216 217 RB_INIT(&mmio_rbroot); 218 } 219