arch/sparc64/kernel/module.c

   1 /* Kernel module help for sparc64.
   2  *
   3  * Copyright (C) 2001 Rusty Russell.
   4  * Copyright (C) 2002 David S. Miller.
   5  */
   6
   7 #include <linux/moduleloader.h>
   8 #include <linux/kernel.h>
   9 #include <linux/elf.h>
  10 #include <linux/vmalloc.h>
  11 #include <linux/fs.h>
  12 #include <linux/string.h>
  13 #include <linux/slab.h>
  14 #include <linux/vmalloc.h>
  15 #include <linux/mm.h>
  16
  17 static struct vm_struct * modvmlist = NULL;
  18
  19 static void module_unmap(void * addr)
  20 {
  21         struct vm_struct **p, *tmp;
  22         int i;
  23
  24         if (!addr)
  25                 return;
  26         if ((PAGE_SIZE-1) & (unsigned long) addr) {
  27                 printk("Trying to unmap module with bad address (%p)\n", addr);
  28                 return;
  29         }
  30
  31         for (p = &modvmlist ; (tmp = *p) ; p = &tmp->next) {
  32                 if (tmp->addr == addr) {
  33                         *p = tmp->next;
  34                         goto found;
  35                 }
  36         }
  37         printk("Trying to unmap nonexistent module vm area (%p)\n", addr);
  38         return;
  39
  40 found:
  41         unmap_vm_area(tmp);
  42
  43         for (i = 0; i < tmp->nr_pages; i++) {
  44                 if (unlikely(!tmp->pages[i]))
  45                         BUG();
  46                 __free_page(tmp->pages[i]);
  47         }
  48
  49         kfree(tmp->pages);
  50         kfree(tmp);
  51 }
  52
  53
  54 static void *module_map(unsigned long size)
  55 {
  56         struct vm_struct **p, *tmp, *area;
  57         struct page **pages;
  58         void * addr;
  59         unsigned int nr_pages, array_size, i;
  60
  61         size = PAGE_ALIGN(size);
  62         if (!size || size > MODULES_LEN)
  63                 return NULL;
  64
  65         addr = (void *) MODULES_VADDR;
  66         for (p = &modvmlist; (tmp = *p) ; p = &tmp->next) {
  67                 if (size + (unsigned long) addr < (unsigned long) tmp->addr)
  68                         break;
  69                 addr = (void *) (tmp->size + (unsigned long) tmp->addr);
  70         }
  71         if ((unsigned long) addr + size >= MODULES_END)
  72                 return NULL;
  73
  74         area = (struct vm_struct *) kmalloc(sizeof(*area), GFP_KERNEL);
  75         if (!area)
  76                 return NULL;
  77         area->size = size + PAGE_SIZE;
  78         area->addr = addr;
  79         area->next = *p;
  80         area->pages = NULL;
  81         area->nr_pages = 0;
  82         area->phys_addr = 0;
  83         *p = area;
  84
  85         nr_pages = size >> PAGE_SHIFT;
  86         array_size = (nr_pages * sizeof(struct page *));
  87
  88         area->nr_pages = nr_pages;
  89         area->pages = pages = kmalloc(array_size, GFP_KERNEL);
  90         if (!area->pages)
  91                 goto fail;
  92
  93         memset(area->pages, 0, array_size);
  94
  95         for (i = 0; i < area->nr_pages; i++) {
  96                 area->pages[i] = alloc_page(GFP_KERNEL);
  97                 if (unlikely(!area->pages[i]))
  98                         goto fail;
  99         }
 100
 101         if (map_vm_area(area, PAGE_KERNEL, &pages)) {
 102                 unmap_vm_area(area);
 103                 goto fail;
 104         }
 105
 106         return area->addr;
 107
 108 fail:
 109         if (area->pages) {
 110                 for (i = 0; i < area->nr_pages; i++) {
 111                         if (area->pages[i])
 112                                 __free_page(area->pages[i]);
 113                 }
 114                 kfree(area->pages);
 115         }
 116         kfree(area);
 117
 118         return NULL;
 119 }
 120
 121 void *module_alloc(unsigned long size)
 122 {
 123         void *ret;
 124
 125         /* We handle the zero case fine, unlike vmalloc */
 126         if (size == 0)
 127                 return NULL;
 128
 129         ret = module_map(size);
 130         if (!ret)
 131                 ret = ERR_PTR(-ENOMEM);
 132         else
 133                 memset(ret, 0, size);
 134
 135         return ret;
 136 }
 137
 138 /* Free memory returned from module_core_alloc/module_init_alloc */
 139 void module_free(struct module *mod, void *module_region)
 140 {
 141         module_unmap(module_region);
 142         /* FIXME: If module_region == mod->init_region, trim exception
 143            table entries. */
 144 }
 145
 146 /* Make generic code ignore STT_REGISTER dummy undefined symbols.  */
 147 int module_frob_arch_sections(Elf_Ehdr *hdr,
 148                               Elf_Shdr *sechdrs,
 149                               char *secstrings,
 150                               struct module *mod)
 151 {
 152         unsigned int symidx;
 153         Elf64_Sym *sym;
 154         const char *strtab;
 155         int i;
 156
 157         for (symidx = 0; sechdrs[symidx].sh_type != SHT_SYMTAB; symidx++) {
 158                 if (symidx == hdr->e_shnum-1) {
 159                         printk("%s: no symtab found.\n", mod->name);
 160                         return -ENOEXEC;
 161                 }
 162         }
 163         sym = (Elf64_Sym *)sechdrs[symidx].sh_addr;
 164         strtab = (char *)sechdrs[sechdrs[symidx].sh_link].sh_addr;
 165
 166         for (i = 1; i < sechdrs[symidx].sh_size / sizeof(Elf_Sym); i++) {
 167                 if (sym[i].st_shndx == SHN_UNDEF &&
 168                     ELF64_ST_TYPE(sym[i].st_info) == STT_REGISTER)
 169                         sym[i].st_shndx = SHN_ABS;
 170         }
 171         return 0;
 172 }
 173
 174 int apply_relocate(Elf64_Shdr *sechdrs,
 175                    const char *strtab,
 176                    unsigned int symindex,
 177                    unsigned int relsec,
 178                    struct module *me)
 179 {
 180         printk(KERN_ERR "module %s: non-ADD RELOCATION unsupported\n",
 181                me->name);
 182         return -ENOEXEC;
 183 }
 184
 185 int apply_relocate_add(Elf64_Shdr *sechdrs,
 186                        const char *strtab,
 187                        unsigned int symindex,
 188                        unsigned int relsec,
 189                        struct module *me)
 190 {
 191         unsigned int i;
 192         Elf64_Rela *rel = (void *)sechdrs[relsec].sh_addr;
 193         Elf64_Sym *sym;
 194         u8 *location;
 195         u32 *loc32;
 196
 197         for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
 198                 Elf64_Addr v;
 199
 200                 /* This is where to make the change */
 201                 location = (u8 *)sechdrs[sechdrs[relsec].sh_info].sh_addr
 202                         + rel[i].r_offset;
 203                 loc32 = (u32 *) location;
 204
 205                 BUG_ON(((u64)location >> (u64)32) != (u64)0);
 206
 207                 /* This is the symbol it is referring to.  Note that all
 208                    undefined symbols have been resolved.  */
 209                 sym = (Elf64_Sym *)sechdrs[symindex].sh_addr
 210                         + ELF64_R_SYM(rel[i].r_info);
 211                 v = sym->st_value + rel[i].r_addend;
 212
 213                 switch (ELF64_R_TYPE(rel[i].r_info) & 0xff) {
 214                 case R_SPARC_64:
 215                         location[0] = v >> 56;
 216                         location[1] = v >> 48;
 217                         location[2] = v >> 40;
 218                         location[3] = v >> 32;
 219                         location[4] = v >> 24;
 220                         location[5] = v >> 16;
 221                         location[6] = v >>  8;
 222                         location[7] = v >>  0;
 223                         break;
 224
 225                 case R_SPARC_32:
 226                         location[0] = v >> 24;
 227                         location[1] = v >> 16;
 228                         location[2] = v >>  8;
 229                         location[3] = v >>  0;
 230                         break;
 231
 232                 case R_SPARC_WDISP30:
 233                         v -= (Elf64_Addr) location;
 234                         *loc32 = (*loc32 & ~0x3fffffff) |
 235                                 ((v >> 2) & 0x3fffffff);
 236                         break;
 237
 238                 case R_SPARC_WDISP22:
 239                         v -= (Elf64_Addr) location;
 240                         *loc32 = (*loc32 & ~0x3fffff) |
 241                                 ((v >> 2) & 0x3fffff);
 242                         break;
 243
 244                 case R_SPARC_LO10:
 245                         *loc32 = (*loc32 & ~0x3ff) | (v & 0x3ff);
 246                         break;
 247
 248                 case R_SPARC_HI22:
 249                         *loc32 = (*loc32 & ~0x3fffff) |
 250                                 ((v >> 10) & 0x3fffff);
 251                         break;
 252
 253                 case R_SPARC_OLO10:
 254                         *loc32 = (*loc32 & ~0x1fff) |
 255                                 (((v & 0x3ff) +
 256                                   (ELF64_R_TYPE(rel[i].r_info) >> 8))
 257                                  & 0x1fff);
 258                         break;
 259
 260                 default:
 261                         printk(KERN_ERR "module %s: Unknown relocation: %x\n",
 262                                me->name,
 263                                (int) (ELF64_R_TYPE(rel[i].r_info) & 0xff));
 264                         return -ENOEXEC;
 265                 };
 266         }
 267         return 0;
 268 }
 269
 270 int module_finalize(const Elf_Ehdr *hdr,
 271                     const Elf_Shdr *sechdrs,
 272                     struct module *me)
 273 {
 274         return 0;
 275 }