sys/platform/vkernel64/platform/copyio.c

   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 uint64_t
  46 casu64(volatile uint64_t *p, uint64_t oldval, uint64_t newval)
  47 {
  48         struct vmspace *vm = curproc->p_vmspace;
  49         vm_offset_t kva;
  50         vm_page_t m;
  51         volatile uint64_t *dest;
  52         uint64_t res;
  53         int error;
  54         int busy;
  55
  56         /* XXX No idea how to handle this case in a simple way, just abort */
  57         if (PAGE_SIZE - ((vm_offset_t)p & PAGE_MASK) < sizeof(uint64_t))
  58                 return -1;
  59
  60         m = vm_fault_page(&vm->vm_map, trunc_page((vm_offset_t)p),
  61                           VM_PROT_READ|VM_PROT_WRITE,
  62                           VM_FAULT_NORMAL,
  63                           &error, &busy);
  64         if (error)
  65                 return -1;
  66         KKASSERT(m->busy == 0);
  67
  68         kva = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m));
  69         dest = (uint64_t *)(kva + ((vm_offset_t)p & PAGE_MASK));
  70         res = oldval;
  71         __asm __volatile(MPLOCKED "cmpxchgq %2,%1; " \
  72                          : "+a" (res), "=m" (*dest) \
  73                          : "r" (newval), "m" (*dest) \
  74                          : "memory");
  75
  76         if (busy)
  77                 vm_page_wakeup(m);
  78         else
  79                 vm_page_unhold(m);
  80
  81         return res;
  82 }
  83
  84 u_int
  85 casu32(volatile u_int *p, u_int oldval, u_int newval)
  86 {
  87         struct vmspace *vm = curproc->p_vmspace;
  88         vm_offset_t kva;
  89         vm_page_t m;
  90         volatile u_int *dest;
  91         u_int res;
  92         int error;
  93         int busy;
  94
  95         /* XXX No idea how to handle this case in a simple way, just abort */
  96         if (PAGE_SIZE - ((vm_offset_t)p & PAGE_MASK) < sizeof(u_int))
  97                 return -1;
  98
  99         m = vm_fault_page(&vm->vm_map, trunc_page((vm_offset_t)p),
 100                           VM_PROT_READ|VM_PROT_WRITE,
 101                           VM_FAULT_NORMAL,
 102                           &error, &busy);
 103         if (error)
 104                 return -1;
 105         KKASSERT(m->busy == 0);
 106
 107         kva = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m));
 108         dest = (u_int *)(kva + ((vm_offset_t)p & PAGE_MASK));
 109         res = oldval;
 110         __asm __volatile(MPLOCKED "cmpxchgl %2,%1; " \
 111                          : "+a" (res), "=m" (*dest) \
 112                          : "r" (newval), "m" (*dest) \
 113                          : "memory");
 114
 115         if (busy)
 116                 vm_page_wakeup(m);
 117         else
 118                 vm_page_unhold(m);
 119
 120         return res;
 121 }
 122
 123 uint64_t
 124 swapu64(volatile uint64_t *p, uint64_t val)
 125 {
 126         struct vmspace *vm = curproc->p_vmspace;
 127         vm_offset_t kva;
 128         vm_page_t m;
 129         uint64_t res;
 130         int error;
 131         int busy;
 132
 133         /* XXX No idea how to handle this case in a simple way, just abort */
 134         if (PAGE_SIZE - ((vm_offset_t)p & PAGE_MASK) < sizeof(uint64_t))
 135                 return -1;
 136
 137         m = vm_fault_page(&vm->vm_map, trunc_page((vm_offset_t)p),
 138                           VM_PROT_READ|VM_PROT_WRITE,
 139                           VM_FAULT_NORMAL,
 140                           &error, &busy);
 141         if (error)
 142                 return -1;
 143         KKASSERT(m->busy == 0);
 144
 145         kva = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m));
 146         res = atomic_swap_long((uint64_t *)(kva + ((vm_offset_t)p & PAGE_MASK)),
 147                                val);
 148         if (busy)
 149                 vm_page_wakeup(m);
 150         else
 151                 vm_page_unhold(m);
 152
 153         return res;
 154 }
 155
 156 uint32_t
 157 swapu32(volatile uint32_t *p, uint32_t val)
 158 {
 159         struct vmspace *vm = curproc->p_vmspace;
 160         vm_offset_t kva;
 161         vm_page_t m;
 162         u_int res;
 163         int error;
 164         int busy;
 165
 166         /* XXX No idea how to handle this case in a simple way, just abort */
 167         if (PAGE_SIZE - ((vm_offset_t)p & PAGE_MASK) < sizeof(uint64_t))
 168                 return -1;
 169
 170         m = vm_fault_page(&vm->vm_map, trunc_page((vm_offset_t)p),
 171                           VM_PROT_READ|VM_PROT_WRITE,
 172                           VM_FAULT_NORMAL,
 173                           &error, &busy);
 174         if (error)
 175                 return -1;
 176         KKASSERT(m->busy == 0);
 177
 178         kva = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m));
 179         res = atomic_swap_int((u_int *)(kva + ((vm_offset_t)p & PAGE_MASK)),
 180                                val);
 181         if (busy)
 182                 vm_page_wakeup(m);
 183         else
 184                 vm_page_unhold(m);
 185
 186         return res;
 187 }
 188
 189 int
 190 copystr(const void *kfaddr, void *kdaddr, size_t len, size_t *lencopied)
 191 {
 192         size_t i;
 193
 194         for (i = 0; i < len; ++i) {
 195                 if ((((char *)kdaddr)[i] = ((const char *)kfaddr)[i]) == 0) {
 196                         if (lencopied)
 197                                 *lencopied = i + 1;
 198                         return(0);
 199                 }
 200         }
 201         return (ENAMETOOLONG);
 202 }
 203
 204 /*
 205  * Copies a NUL-terminated string from user space to kernel space.
 206  * The number of bytes copied, including the terminator, is returned in
 207  * (*res).
 208  *
 209  * Returns 0 on success, EFAULT or ENAMETOOLONG on failure.
 210  */
 211 int
 212 copyinstr(const void *udaddr, void *kaddr, size_t len, size_t *res)
 213 {
 214         int error;
 215         size_t n;
 216         const char *uptr = udaddr;
 217         char *kptr = kaddr;
 218
 219         if (res)
 220                 *res = 0;
 221         while (len) {
 222                 n = PAGE_SIZE - ((vm_offset_t)uptr & PAGE_MASK);
 223                 if (n > 32)
 224                         n = 32;
 225                 if (n > len)
 226                         n = len;
 227                 if ((error = copyin(uptr, kptr, n)) != 0)
 228                         return(error);
 229                 while (n) {
 230                         if (res)
 231                                 ++*res;
 232                         if (*kptr == 0)
 233                                 return(0);
 234                         ++kptr;
 235                         ++uptr;
 236                         --n;
 237                         --len;
 238                 }
 239
 240         }
 241         return(ENAMETOOLONG);
 242 }
 243
 244 /*
 245  * Copy a binary buffer from user space to kernel space.
 246  *
 247  * Returns 0 on success, EFAULT on failure.
 248  */
 249 int
 250 copyin(const void *udaddr, void *kaddr, size_t len)
 251 {
 252         struct vmspace *vm = curproc->p_vmspace;
 253         struct lwbuf *lwb;
 254         struct lwbuf lwb_cache;
 255         vm_page_t m;
 256         int error;
 257         size_t n;
 258
 259         error = 0;
 260         while (len) {
 261                 m = vm_fault_page(&vm->vm_map, trunc_page((vm_offset_t)udaddr),
 262                                   VM_PROT_READ,
 263                                   VM_FAULT_NORMAL,
 264                                   &error, NULL);
 265                 if (error)
 266                         break;
 267                 n = PAGE_SIZE - ((vm_offset_t)udaddr & PAGE_MASK);
 268                 if (n > len)
 269                         n = len;
 270                 lwb = lwbuf_alloc(m, &lwb_cache);
 271                 bcopy((char *)lwbuf_kva(lwb)+((vm_offset_t)udaddr & PAGE_MASK),
 272                       kaddr, n);
 273                 len -= n;
 274                 udaddr = (const char *)udaddr + n;
 275                 kaddr = (char *)kaddr + n;
 276                 lwbuf_free(lwb);
 277                 vm_page_unhold(m);
 278         }
 279         if (error)
 280                 error = EFAULT;
 281         return (error);
 282 }
 283
 284 /*
 285  * Copy a binary buffer from kernel space to user space.
 286  *
 287  * Returns 0 on success, EFAULT on failure.
 288  */
 289 int
 290 copyout(const void *kaddr, void *udaddr, size_t len)
 291 {
 292         struct vmspace *vm = curproc->p_vmspace;
 293         struct lwbuf *lwb;
 294         struct lwbuf lwb_cache;
 295         vm_page_t m;
 296         int error;
 297         int busy;
 298         size_t n;
 299
 300         error = 0;
 301         while (len) {
 302                 m = vm_fault_page(&vm->vm_map, trunc_page((vm_offset_t)udaddr),
 303                                   VM_PROT_READ|VM_PROT_WRITE,
 304                                   VM_FAULT_NORMAL,
 305                                   &error, &busy);
 306                 if (error)
 307                         break;
 308                 KKASSERT(m->busy == 0);
 309                 n = PAGE_SIZE - ((vm_offset_t)udaddr & PAGE_MASK);
 310                 if (n > len)
 311                         n = len;
 312                 lwb = lwbuf_alloc(m, &lwb_cache);
 313                 bcopy(kaddr, (char *)lwbuf_kva(lwb) +
 314                              ((vm_offset_t)udaddr & PAGE_MASK), n);
 315                 len -= n;
 316                 udaddr = (char *)udaddr + n;
 317                 kaddr = (const char *)kaddr + n;
 318                 lwbuf_free(lwb);
 319                 if (busy)
 320                         vm_page_wakeup(m);
 321                 else
 322                         vm_page_unhold(m);
 323         }
 324         if (error)
 325                 error = EFAULT;
 326         return (error);
 327 }
 328
 329 /*
 330  * Fetch the byte at the specified user address.  Returns -1 on failure.
 331  */
 332 int
 333 fubyte(const uint8_t *base)
 334 {
 335         uint8_t c;
 336
 337         if (copyin(base, &c, 1) == 0)
 338                 return((int)c);
 339         return(-1);
 340 }
 341
 342 /*
 343  * Store a byte at the specified user address.  Returns -1 on failure.
 344  */
 345 int
 346 subyte(uint8_t *base, uint8_t byte)
 347 {
 348         uint8_t c = byte;
 349
 350         if (copyout(&c, base, 1) == 0)
 351                 return(0);
 352         return(-1);
 353 }
 354
 355 /*
 356  * Fetch a word (integer, 32 bits) from user space
 357  */
 358 int32_t
 359 fuword32(const uint32_t *base)
 360 {
 361         uint32_t v;
 362
 363         if (copyin(base, &v, sizeof(v)) == 0)
 364                 return(v);
 365         return(-1);
 366 }
 367
 368 /*
 369  * Fetch a word (integer, 32 bits) from user space
 370  */
 371 int64_t
 372 fuword64(const uint64_t *base)
 373 {
 374         uint64_t v;
 375
 376         if (copyin(base, &v, sizeof(v)) == 0)
 377                 return(v);
 378         return(-1);
 379 }
 380
 381 /*
 382  * Store a word (integer, 32 bits) to user space
 383  */
 384 int
 385 suword64(uint64_t *base, uint64_t word)
 386 {
 387         if (copyout(&word, base, sizeof(word)) == 0)
 388                 return(0);
 389         return(-1);
 390 }
 391
 392 int
 393 suword32(uint32_t *base, int word)
 394 {
 395         if (copyout(&word, base, sizeof(word)) == 0)
 396                 return(0);
 397         return(-1);
 398 }