| 1 | /* |
| 2 | * Copyright (c) 2006 The DragonFly Project. All rights reserved. |
| 3 | * |
| 4 | * This code is derived from software contributed to The DragonFly Project |
| 5 | * by Matthew Dillon <dillon@backplane.com> |
| 6 | * |
| 7 | * Redistribution and use in source and binary forms, with or without |
| 8 | * modification, are permitted provided that the following conditions |
| 9 | * are met: |
| 10 | * |
| 11 | * 1. Redistributions of source code must retain the above copyright |
| 12 | * notice, this list of conditions and the following disclaimer. |
| 13 | * 2. Redistributions in binary form must reproduce the above copyright |
| 14 | * notice, this list of conditions and the following disclaimer in |
| 15 | * the documentation and/or other materials provided with the |
| 16 | * distribution. |
| 17 | * 3. Neither the name of The DragonFly Project nor the names of its |
| 18 | * contributors may be used to endorse or promote products derived |
| 19 | * from this software without specific, prior written permission. |
| 20 | * |
| 21 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 22 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 23 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| 24 | * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| 25 | * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 26 | * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, |
| 27 | * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| 28 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED |
| 29 | * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| 30 | * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| 31 | * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 32 | * SUCH DAMAGE. |
| 33 | */ |
| 34 | |
| 35 | #include <sys/types.h> |
| 36 | #include <sys/systm.h> |
| 37 | #include <cpu/lwbuf.h> |
| 38 | #include <vm/vm_page.h> |
| 39 | #include <vm/vm_extern.h> |
| 40 | #include <assert.h> |
| 41 | |
| 42 | #include <sys/stat.h> |
| 43 | #include <sys/mman.h> |
| 44 | |
| 45 | /* |
| 46 | * A bcopy that works dring low level boot, before FP is working |
| 47 | */ |
| 48 | void |
| 49 | ovbcopy(const void *src, void *dst, size_t len) |
| 50 | { |
| 51 | bcopy(src, dst, len); |
| 52 | } |
| 53 | |
| 54 | void |
| 55 | bcopyi(const void *src, void *dst, size_t len) |
| 56 | { |
| 57 | bcopy(src, dst, len); |
| 58 | } |
| 59 | |
| 60 | int |
| 61 | copystr(const void *kfaddr, void *kdaddr, size_t len, size_t *lencopied) |
| 62 | { |
| 63 | size_t i; |
| 64 | |
| 65 | for (i = 0; i < len; ++i) { |
| 66 | if ((((char *)kdaddr)[i] = ((const char *)kfaddr)[i]) == 0) { |
| 67 | if (lencopied) |
| 68 | *lencopied = i + 1; |
| 69 | return(0); |
| 70 | } |
| 71 | } |
| 72 | return (ENAMETOOLONG); |
| 73 | } |
| 74 | |
| 75 | /* |
| 76 | * Copies a NUL-terminated string from user space to kernel space. |
| 77 | * The number of bytes copied, including the terminator, is returned in |
| 78 | * (*res). |
| 79 | * |
| 80 | * Returns 0 on success, EFAULT or ENAMETOOLONG on failure. |
| 81 | */ |
| 82 | int |
| 83 | copyinstr(const void *udaddr, void *kaddr, size_t len, size_t *res) |
| 84 | { |
| 85 | int error; |
| 86 | size_t n; |
| 87 | const char *uptr = udaddr; |
| 88 | char *kptr = kaddr; |
| 89 | |
| 90 | if (res) |
| 91 | *res = 0; |
| 92 | while (len) { |
| 93 | n = PAGE_SIZE - ((vm_offset_t)uptr & PAGE_MASK); |
| 94 | if (n > 32) |
| 95 | n = 32; |
| 96 | if (n > len) |
| 97 | n = len; |
| 98 | if ((error = copyin(uptr, kptr, n)) != 0) |
| 99 | return(error); |
| 100 | while (n) { |
| 101 | if (res) |
| 102 | ++*res; |
| 103 | if (*kptr == 0) |
| 104 | return(0); |
| 105 | ++kptr; |
| 106 | ++uptr; |
| 107 | --n; |
| 108 | --len; |
| 109 | } |
| 110 | |
| 111 | } |
| 112 | return(ENAMETOOLONG); |
| 113 | } |
| 114 | |
| 115 | /* |
| 116 | * Copy a binary buffer from user space to kernel space. |
| 117 | * |
| 118 | * NOTE: on a real system copyin/copyout are MP safe, but the current |
| 119 | * implementation on a vkernel is not so we get the mp lock. |
| 120 | * |
| 121 | * Returns 0 on success, EFAULT on failure. |
| 122 | */ |
| 123 | int |
| 124 | copyin(const void *udaddr, void *kaddr, size_t len) |
| 125 | { |
| 126 | struct vmspace *vm = curproc->p_vmspace; |
| 127 | struct lwbuf *lwb; |
| 128 | struct lwbuf_cache lwb_cache; |
| 129 | vm_page_t m; |
| 130 | int error; |
| 131 | size_t n; |
| 132 | |
| 133 | error = 0; |
| 134 | while (len) { |
| 135 | m = vm_fault_page(&vm->vm_map, trunc_page((vm_offset_t)udaddr), |
| 136 | VM_PROT_READ, |
| 137 | VM_FAULT_NORMAL, &error); |
| 138 | if (error) |
| 139 | break; |
| 140 | n = PAGE_SIZE - ((vm_offset_t)udaddr & PAGE_MASK); |
| 141 | if (n > len) |
| 142 | n = len; |
| 143 | lwb = lwbuf_alloc(m, &lwb_cache); |
| 144 | bcopy((char *)lwbuf_kva(lwb)+((vm_offset_t)udaddr & PAGE_MASK), |
| 145 | kaddr, n); |
| 146 | len -= n; |
| 147 | udaddr = (const char *)udaddr + n; |
| 148 | kaddr = (char *)kaddr + n; |
| 149 | lwbuf_free(lwb); |
| 150 | vm_page_unhold(m); |
| 151 | } |
| 152 | return (error); |
| 153 | } |
| 154 | |
| 155 | /* |
| 156 | * Copy a binary buffer from kernel space to user space. |
| 157 | * |
| 158 | * Returns 0 on success, EFAULT on failure. |
| 159 | */ |
| 160 | int |
| 161 | copyout(const void *kaddr, void *udaddr, size_t len) |
| 162 | { |
| 163 | struct vmspace *vm = curproc->p_vmspace; |
| 164 | struct lwbuf *lwb; |
| 165 | struct lwbuf lwb_cache; |
| 166 | vm_page_t m; |
| 167 | int error; |
| 168 | size_t n; |
| 169 | |
| 170 | error = 0; |
| 171 | while (len) { |
| 172 | m = vm_fault_page(&vm->vm_map, trunc_page((vm_offset_t)udaddr), |
| 173 | VM_PROT_READ|VM_PROT_WRITE, |
| 174 | VM_FAULT_NORMAL, &error); |
| 175 | if (error) |
| 176 | break; |
| 177 | n = PAGE_SIZE - ((vm_offset_t)udaddr & PAGE_MASK); |
| 178 | if (n > len) |
| 179 | n = len; |
| 180 | lwb = lwbuf_alloc(m, &lwb_cache); |
| 181 | bcopy(kaddr, (char *)lwbuf_kva(lwb) + |
| 182 | ((vm_offset_t)udaddr & PAGE_MASK), n); |
| 183 | len -= n; |
| 184 | udaddr = (char *)udaddr + n; |
| 185 | kaddr = (const char *)kaddr + n; |
| 186 | vm_page_dirty(m); |
| 187 | lwbuf_free(lwb); |
| 188 | vm_page_unhold(m); |
| 189 | } |
| 190 | return (error); |
| 191 | } |
| 192 | |
| 193 | /* |
| 194 | * Fetch the byte at the specified user address. Returns -1 on failure. |
| 195 | */ |
| 196 | int |
| 197 | fubyte(const void *base) |
| 198 | { |
| 199 | unsigned char c; |
| 200 | |
| 201 | if (copyin(base, &c, 1) == 0) |
| 202 | return((int)c); |
| 203 | return(-1); |
| 204 | } |
| 205 | |
| 206 | /* |
| 207 | * Store a byte at the specified user address. Returns -1 on failure. |
| 208 | */ |
| 209 | int |
| 210 | subyte (void *base, int byte) |
| 211 | { |
| 212 | unsigned char c = byte; |
| 213 | |
| 214 | if (copyout(&c, base, 1) == 0) |
| 215 | return(0); |
| 216 | return(-1); |
| 217 | } |
| 218 | |
| 219 | /* |
| 220 | * Fetch a word (integer, 32 bits) from user space |
| 221 | */ |
| 222 | long |
| 223 | fuword(const void *base) |
| 224 | { |
| 225 | long v; |
| 226 | |
| 227 | if (copyin(base, &v, sizeof(v)) == 0) |
| 228 | return((long)v); |
| 229 | return(-1); |
| 230 | } |
| 231 | |
| 232 | /* |
| 233 | * Store a word (integer, 32 bits) to user space |
| 234 | */ |
| 235 | int |
| 236 | suword(void *base, long word) |
| 237 | { |
| 238 | if (copyout(&word, base, sizeof(word)) == 0) |
| 239 | return(0); |
| 240 | return(-1); |
| 241 | } |
| 242 | |
| 243 | /* |
| 244 | * Fetch an short word (16 bits) from user space |
| 245 | */ |
| 246 | int |
| 247 | fusword(void *base) |
| 248 | { |
| 249 | unsigned short sword; |
| 250 | |
| 251 | if (copyin(base, &sword, sizeof(sword)) == 0) |
| 252 | return((int)sword); |
| 253 | return(-1); |
| 254 | } |
| 255 | |
| 256 | /* |
| 257 | * Store a short word (16 bits) to user space |
| 258 | */ |
| 259 | int |
| 260 | susword (void *base, int word) |
| 261 | { |
| 262 | unsigned short sword = word; |
| 263 | |
| 264 | if (copyout(&sword, base, sizeof(sword)) == 0) |
| 265 | return(0); |
| 266 | return(-1); |
| 267 | } |