arch/um/kernel/tlb.c

   1 /*
   2  * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include "linux/mm.h"
   7 #include "asm/page.h"
   8 #include "asm/pgalloc.h"
   9 #include "asm/pgtable.h"
  10 #include "asm/tlbflush.h"
  11 #include "choose-mode.h"
  12 #include "mode_kern.h"
  13 #include "as-layout.h"
  14 #include "tlb.h"
  15 #include "mem.h"
  16 #include "mem_user.h"
  17 #include "os.h"
  18
  19 static int add_mmap(unsigned long virt, unsigned long phys, unsigned long len,
  20                     unsigned int prot, struct host_vm_op *ops, int *index,
  21                     int last_filled, union mm_context *mmu, void **flush,
  22                     int (*do_ops)(union mm_context *, struct host_vm_op *,
  23                                   int, int, void **))
  24 {
  25         __u64 offset;
  26         struct host_vm_op *last;
  27         int fd, ret = 0;
  28
  29         fd = phys_mapping(phys, &offset);
  30         if(*index != -1){
  31                 last = &ops[*index];
  32                 if((last->type == MMAP) &&
  33                    (last->u.mmap.addr + last->u.mmap.len == virt) &&
  34                    (last->u.mmap.prot == prot) && (last->u.mmap.fd == fd) &&
  35                    (last->u.mmap.offset + last->u.mmap.len == offset)){
  36                         last->u.mmap.len += len;
  37                         return 0;
  38                 }
  39         }
  40
  41         if(*index == last_filled){
  42                 ret = (*do_ops)(mmu, ops, last_filled, 0, flush);
  43                 *index = -1;
  44         }
  45
  46         ops[++*index] = ((struct host_vm_op) { .type    = MMAP,
  47                                                 .u = { .mmap = {
  48                                                        .addr    = virt,
  49                                                        .len     = len,
  50                                                        .prot    = prot,
  51                                                        .fd      = fd,
  52                                                        .offset  = offset }
  53                            } });
  54         return ret;
  55 }
  56
  57 static int add_munmap(unsigned long addr, unsigned long len,
  58                       struct host_vm_op *ops, int *index, int last_filled,
  59                       union mm_context *mmu, void **flush,
  60                       int (*do_ops)(union mm_context *, struct host_vm_op *,
  61                                     int, int, void **))
  62 {
  63         struct host_vm_op *last;
  64         int ret = 0;
  65
  66         if(*index != -1){
  67                 last = &ops[*index];
  68                 if((last->type == MUNMAP) &&
  69                    (last->u.munmap.addr + last->u.mmap.len == addr)){
  70                         last->u.munmap.len += len;
  71                         return 0;
  72                 }
  73         }
  74
  75         if(*index == last_filled){
  76                 ret = (*do_ops)(mmu, ops, last_filled, 0, flush);
  77                 *index = -1;
  78         }
  79
  80         ops[++*index] = ((struct host_vm_op) { .type    = MUNMAP,
  81                                                .u = { .munmap = {
  82                                                         .addr   = addr,
  83                                                         .len    = len } } });
  84         return ret;
  85 }
  86
  87 static int add_mprotect(unsigned long addr, unsigned long len,
  88                         unsigned int prot, struct host_vm_op *ops, int *index,
  89                         int last_filled, union mm_context *mmu, void **flush,
  90                         int (*do_ops)(union mm_context *, struct host_vm_op *,
  91                                       int, int, void **))
  92 {
  93         struct host_vm_op *last;
  94         int ret = 0;
  95
  96         if(*index != -1){
  97                 last = &ops[*index];
  98                 if((last->type == MPROTECT) &&
  99                    (last->u.mprotect.addr + last->u.mprotect.len == addr) &&
 100                    (last->u.mprotect.prot == prot)){
 101                         last->u.mprotect.len += len;
 102                         return 0;
 103                 }
 104         }
 105
 106         if(*index == last_filled){
 107                 ret = (*do_ops)(mmu, ops, last_filled, 0, flush);
 108                 *index = -1;
 109         }
 110
 111         ops[++*index] = ((struct host_vm_op) { .type    = MPROTECT,
 112                                                .u = { .mprotect = {
 113                                                        .addr    = addr,
 114                                                        .len     = len,
 115                                                        .prot    = prot } } });
 116         return ret;
 117 }
 118
 119 #define ADD_ROUND(n, inc) (((n) + (inc)) & ~((inc) - 1))
 120
 121 static inline int update_pte_range(pmd_t *pmd, unsigned long addr,
 122                                    unsigned long end, struct host_vm_op *ops,
 123                                    int last_op, int *op_index, int force,
 124                                    union mm_context *mmu, void **flush,
 125                                    int (*do_ops)(union mm_context *,
 126                                                  struct host_vm_op *, int, int,
 127                                                  void **))
 128 {
 129         pte_t *pte;
 130         int r, w, x, prot, ret = 0;
 131
 132         pte = pte_offset_kernel(pmd, addr);
 133         do {
 134                 r = pte_read(*pte);
 135                 w = pte_write(*pte);
 136                 x = pte_exec(*pte);
 137                 if (!pte_young(*pte)) {
 138                         r = 0;
 139                         w = 0;
 140                 } else if (!pte_dirty(*pte)) {
 141                         w = 0;
 142                 }
 143                 prot = ((r ? UM_PROT_READ : 0) | (w ? UM_PROT_WRITE : 0) |
 144                         (x ? UM_PROT_EXEC : 0));
 145                 if(force || pte_newpage(*pte)){
 146                         if(pte_present(*pte))
 147                                 ret = add_mmap(addr, pte_val(*pte) & PAGE_MASK,
 148                                                PAGE_SIZE, prot, ops, op_index,
 149                                                last_op, mmu, flush, do_ops);
 150                         else ret = add_munmap(addr, PAGE_SIZE, ops, op_index,
 151                                               last_op, mmu, flush, do_ops);
 152                 }
 153                 else if(pte_newprot(*pte))
 154                         ret = add_mprotect(addr, PAGE_SIZE, prot, ops, op_index,
 155                                            last_op, mmu, flush, do_ops);
 156                 *pte = pte_mkuptodate(*pte);
 157         } while (pte++, addr += PAGE_SIZE, ((addr != end) && !ret));
 158         return ret;
 159 }
 160
 161 static inline int update_pmd_range(pud_t *pud, unsigned long addr,
 162                                    unsigned long end, struct host_vm_op *ops,
 163                                    int last_op, int *op_index, int force,
 164                                    union mm_context *mmu, void **flush,
 165                                    int (*do_ops)(union mm_context *,
 166                                                  struct host_vm_op *, int, int,
 167                                                  void **))
 168 {
 169         pmd_t *pmd;
 170         unsigned long next;
 171         int ret = 0;
 172
 173         pmd = pmd_offset(pud, addr);
 174         do {
 175                 next = pmd_addr_end(addr, end);
 176                 if(!pmd_present(*pmd)){
 177                         if(force || pmd_newpage(*pmd)){
 178                                 ret = add_munmap(addr, next - addr, ops,
 179                                                  op_index, last_op, mmu,
 180                                                  flush, do_ops);
 181                                 pmd_mkuptodate(*pmd);
 182                         }
 183                 }
 184                 else ret = update_pte_range(pmd, addr, next, ops, last_op,
 185                                             op_index, force, mmu, flush,
 186                                             do_ops);
 187         } while (pmd++, addr = next, ((addr != end) && !ret));
 188         return ret;
 189 }
 190
 191 static inline int update_pud_range(pgd_t *pgd, unsigned long addr,
 192                                    unsigned long end, struct host_vm_op *ops,
 193                                    int last_op, int *op_index, int force,
 194                                    union mm_context *mmu, void **flush,
 195                                    int (*do_ops)(union mm_context *,
 196                                                  struct host_vm_op *, int, int,
 197                                                  void **))
 198 {
 199         pud_t *pud;
 200         unsigned long next;
 201         int ret = 0;
 202
 203         pud = pud_offset(pgd, addr);
 204         do {
 205                 next = pud_addr_end(addr, end);
 206                 if(!pud_present(*pud)){
 207                         if(force || pud_newpage(*pud)){
 208                                 ret = add_munmap(addr, next - addr, ops,
 209                                                  op_index, last_op, mmu,
 210                                                  flush, do_ops);
 211                                 pud_mkuptodate(*pud);
 212                         }
 213                 }
 214                 else ret = update_pmd_range(pud, addr, next, ops, last_op,
 215                                             op_index, force, mmu, flush,
 216                                             do_ops);
 217         } while (pud++, addr = next, ((addr != end) && !ret));
 218         return ret;
 219 }
 220
 221 void fix_range_common(struct mm_struct *mm, unsigned long start_addr,
 222                       unsigned long end_addr, int force,
 223                       int (*do_ops)(union mm_context *, struct host_vm_op *,
 224                                     int, int, void **))
 225 {
 226         pgd_t *pgd;
 227         union mm_context *mmu = &mm->context;
 228         struct host_vm_op ops[1];
 229         unsigned long addr = start_addr, next;
 230         int ret = 0, last_op = ARRAY_SIZE(ops) - 1, op_index = -1;
 231         void *flush = NULL;
 232
 233         ops[0].type = NONE;
 234         pgd = pgd_offset(mm, addr);
 235         do {
 236                 next = pgd_addr_end(addr, end_addr);
 237                 if(!pgd_present(*pgd)){
 238                         if (force || pgd_newpage(*pgd)){
 239                                 ret = add_munmap(addr, next - addr, ops,
 240                                                  &op_index, last_op, mmu,
 241                                                  &flush, do_ops);
 242                                 pgd_mkuptodate(*pgd);
 243                         }
 244                 }
 245                 else ret = update_pud_range(pgd, addr, next, ops, last_op,
 246                                             &op_index, force, mmu, &flush,
 247                                             do_ops);
 248         } while (pgd++, addr = next, ((addr != end_addr) && !ret));
 249
 250         if(!ret)
 251                 ret = (*do_ops)(mmu, ops, op_index, 1, &flush);
 252
 253         /* This is not an else because ret is modified above */
 254         if(ret) {
 255                 printk("fix_range_common: failed, killing current process\n");
 256                 force_sig(SIGKILL, current);
 257         }
 258 }
 259
 260 int flush_tlb_kernel_range_common(unsigned long start, unsigned long end)
 261 {
 262         struct mm_struct *mm;
 263         pgd_t *pgd;
 264         pud_t *pud;
 265         pmd_t *pmd;
 266         pte_t *pte;
 267         unsigned long addr, last;
 268         int updated = 0, err;
 269
 270         mm = &init_mm;
 271         for(addr = start; addr < end;){
 272                 pgd = pgd_offset(mm, addr);
 273                 if(!pgd_present(*pgd)){
 274                         last = ADD_ROUND(addr, PGDIR_SIZE);
 275                         if(last > end)
 276                                 last = end;
 277                         if(pgd_newpage(*pgd)){
 278                                 updated = 1;
 279                                 err = os_unmap_memory((void *) addr,
 280                                                       last - addr);
 281                                 if(err < 0)
 282                                         panic("munmap failed, errno = %d\n",
 283                                               -err);
 284                         }
 285                         addr = last;
 286                         continue;
 287                 }
 288
 289                 pud = pud_offset(pgd, addr);
 290                 if(!pud_present(*pud)){
 291                         last = ADD_ROUND(addr, PUD_SIZE);
 292                         if(last > end)
 293                                 last = end;
 294                         if(pud_newpage(*pud)){
 295                                 updated = 1;
 296                                 err = os_unmap_memory((void *) addr,
 297                                                       last - addr);
 298                                 if(err < 0)
 299                                         panic("munmap failed, errno = %d\n",
 300                                               -err);
 301                         }
 302                         addr = last;
 303                         continue;
 304                 }
 305
 306                 pmd = pmd_offset(pud, addr);
 307                 if(!pmd_present(*pmd)){
 308                         last = ADD_ROUND(addr, PMD_SIZE);
 309                         if(last > end)
 310                                 last = end;
 311                         if(pmd_newpage(*pmd)){
 312                                 updated = 1;
 313                                 err = os_unmap_memory((void *) addr,
 314                                                       last - addr);
 315                                 if(err < 0)
 316                                         panic("munmap failed, errno = %d\n",
 317                                               -err);
 318                         }
 319                         addr = last;
 320                         continue;
 321                 }
 322
 323                 pte = pte_offset_kernel(pmd, addr);
 324                 if(!pte_present(*pte) || pte_newpage(*pte)){
 325                         updated = 1;
 326                         err = os_unmap_memory((void *) addr,
 327                                               PAGE_SIZE);
 328                         if(err < 0)
 329                                 panic("munmap failed, errno = %d\n",
 330                                       -err);
 331                         if(pte_present(*pte))
 332                                 map_memory(addr,
 333                                            pte_val(*pte) & PAGE_MASK,
 334                                            PAGE_SIZE, 1, 1, 1);
 335                 }
 336                 else if(pte_newprot(*pte)){
 337                         updated = 1;
 338                         os_protect_memory((void *) addr, PAGE_SIZE, 1, 1, 1);
 339                 }
 340                 addr += PAGE_SIZE;
 341         }
 342         return(updated);
 343 }
 344
 345 pgd_t *pgd_offset_proc(struct mm_struct *mm, unsigned long address)
 346 {
 347         return(pgd_offset(mm, address));
 348 }
 349
 350 pud_t *pud_offset_proc(pgd_t *pgd, unsigned long address)
 351 {
 352         return(pud_offset(pgd, address));
 353 }
 354
 355 pmd_t *pmd_offset_proc(pud_t *pud, unsigned long address)
 356 {
 357         return(pmd_offset(pud, address));
 358 }
 359
 360 pte_t *pte_offset_proc(pmd_t *pmd, unsigned long address)
 361 {
 362         return(pte_offset_kernel(pmd, address));
 363 }
 364
 365 pte_t *addr_pte(struct task_struct *task, unsigned long addr)
 366 {
 367         pgd_t *pgd = pgd_offset(task->mm, addr);
 368         pud_t *pud = pud_offset(pgd, addr);
 369         pmd_t *pmd = pmd_offset(pud, addr);
 370
 371         return(pte_offset_map(pmd, addr));
 372 }
 373
 374 void flush_tlb_all(void)
 375 {
 376         flush_tlb_mm(current->mm);
 377 }
 378
 379 void flush_tlb_kernel_range(unsigned long start, unsigned long end)
 380 {
 381         CHOOSE_MODE_PROC(flush_tlb_kernel_range_tt,
 382                          flush_tlb_kernel_range_common, start, end);
 383 }
 384
 385 void flush_tlb_kernel_vm(void)
 386 {
 387         CHOOSE_MODE(flush_tlb_kernel_vm_tt(),
 388                     flush_tlb_kernel_range_common(start_vm, end_vm));
 389 }
 390
 391 void __flush_tlb_one(unsigned long addr)
 392 {
 393         CHOOSE_MODE_PROC(__flush_tlb_one_tt, __flush_tlb_one_skas, addr);
 394 }
 395
 396 void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
 397                      unsigned long end)
 398 {
 399         CHOOSE_MODE_PROC(flush_tlb_range_tt, flush_tlb_range_skas, vma, start,
 400                          end);
 401 }
 402
 403 void flush_tlb_mm(struct mm_struct *mm)
 404 {
 405         CHOOSE_MODE_PROC(flush_tlb_mm_tt, flush_tlb_mm_skas, mm);
 406 }
 407
 408 void force_flush_all(void)
 409 {
 410         CHOOSE_MODE(force_flush_all_tt(), force_flush_all_skas());
 411 }
 412