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-rw-r--r--arch/metag/kernel/module.c284
1 files changed, 0 insertions, 284 deletions
diff --git a/arch/metag/kernel/module.c b/arch/metag/kernel/module.c
deleted file mode 100644
index bb8dfba9a763..000000000000
--- a/arch/metag/kernel/module.c
+++ /dev/null
@@ -1,284 +0,0 @@
-/* Kernel module help for Meta.
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-*/
-#include <linux/moduleloader.h>
-#include <linux/elf.h>
-#include <linux/vmalloc.h>
-#include <linux/fs.h>
-#include <linux/string.h>
-#include <linux/kernel.h>
-#include <linux/sort.h>
-
-#include <asm/unaligned.h>
-
-/* Count how many different relocations (different symbol, different
- addend) */
-static unsigned int count_relocs(const Elf32_Rela *rela, unsigned int num)
-{
- unsigned int i, r_info, r_addend, _count_relocs;
-
- _count_relocs = 0;
- r_info = 0;
- r_addend = 0;
- for (i = 0; i < num; i++)
- /* Only count relbranch relocs, others don't need stubs */
- if (ELF32_R_TYPE(rela[i].r_info) == R_METAG_RELBRANCH &&
- (r_info != ELF32_R_SYM(rela[i].r_info) ||
- r_addend != rela[i].r_addend)) {
- _count_relocs++;
- r_info = ELF32_R_SYM(rela[i].r_info);
- r_addend = rela[i].r_addend;
- }
-
- return _count_relocs;
-}
-
-static int relacmp(const void *_x, const void *_y)
-{
- const Elf32_Rela *x, *y;
-
- y = (Elf32_Rela *)_x;
- x = (Elf32_Rela *)_y;
-
- /* Compare the entire r_info (as opposed to ELF32_R_SYM(r_info) only) to
- * make the comparison cheaper/faster. It won't affect the sorting or
- * the counting algorithms' performance
- */
- if (x->r_info < y->r_info)
- return -1;
- else if (x->r_info > y->r_info)
- return 1;
- else if (x->r_addend < y->r_addend)
- return -1;
- else if (x->r_addend > y->r_addend)
- return 1;
- else
- return 0;
-}
-
-static void relaswap(void *_x, void *_y, int size)
-{
- uint32_t *x, *y, tmp;
- int i;
-
- y = (uint32_t *)_x;
- x = (uint32_t *)_y;
-
- for (i = 0; i < sizeof(Elf32_Rela) / sizeof(uint32_t); i++) {
- tmp = x[i];
- x[i] = y[i];
- y[i] = tmp;
- }
-}
-
-/* Get the potential trampolines size required of the init and
- non-init sections */
-static unsigned long get_plt_size(const Elf32_Ehdr *hdr,
- const Elf32_Shdr *sechdrs,
- const char *secstrings,
- int is_init)
-{
- unsigned long ret = 0;
- unsigned i;
-
- /* Everything marked ALLOC (this includes the exported
- symbols) */
- for (i = 1; i < hdr->e_shnum; i++) {
- /* If it's called *.init*, and we're not init, we're
- not interested */
- if ((strstr(secstrings + sechdrs[i].sh_name, ".init") != NULL)
- != is_init)
- continue;
-
- /* We don't want to look at debug sections. */
- if (strstr(secstrings + sechdrs[i].sh_name, ".debug") != NULL)
- continue;
-
- if (sechdrs[i].sh_type == SHT_RELA) {
- pr_debug("Found relocations in section %u\n", i);
- pr_debug("Ptr: %p. Number: %u\n",
- (void *)hdr + sechdrs[i].sh_offset,
- sechdrs[i].sh_size / sizeof(Elf32_Rela));
-
- /* Sort the relocation information based on a symbol and
- * addend key. This is a stable O(n*log n) complexity
- * alogrithm but it will reduce the complexity of
- * count_relocs() to linear complexity O(n)
- */
- sort((void *)hdr + sechdrs[i].sh_offset,
- sechdrs[i].sh_size / sizeof(Elf32_Rela),
- sizeof(Elf32_Rela), relacmp, relaswap);
-
- ret += count_relocs((void *)hdr
- + sechdrs[i].sh_offset,
- sechdrs[i].sh_size
- / sizeof(Elf32_Rela))
- * sizeof(struct metag_plt_entry);
- }
- }
-
- return ret;
-}
-
-int module_frob_arch_sections(Elf32_Ehdr *hdr,
- Elf32_Shdr *sechdrs,
- char *secstrings,
- struct module *me)
-{
- unsigned int i;
-
- /* Find .plt and .init.plt sections */
- for (i = 0; i < hdr->e_shnum; i++) {
- if (strcmp(secstrings + sechdrs[i].sh_name, ".init.plt") == 0)
- me->arch.init_plt_section = i;
- else if (strcmp(secstrings + sechdrs[i].sh_name, ".plt") == 0)
- me->arch.core_plt_section = i;
- }
- if (!me->arch.core_plt_section || !me->arch.init_plt_section) {
- pr_err("Module doesn't contain .plt or .init.plt sections.\n");
- return -ENOEXEC;
- }
-
- /* Override their sizes */
- sechdrs[me->arch.core_plt_section].sh_size
- = get_plt_size(hdr, sechdrs, secstrings, 0);
- sechdrs[me->arch.core_plt_section].sh_type = SHT_NOBITS;
- sechdrs[me->arch.init_plt_section].sh_size
- = get_plt_size(hdr, sechdrs, secstrings, 1);
- sechdrs[me->arch.init_plt_section].sh_type = SHT_NOBITS;
- return 0;
-}
-
-/* Set up a trampoline in the PLT to bounce us to the distant function */
-static uint32_t do_plt_call(void *location, Elf32_Addr val,
- Elf32_Shdr *sechdrs, struct module *mod)
-{
- struct metag_plt_entry *entry;
- /* Instructions used to do the indirect jump. */
- uint32_t tramp[2];
-
- /* We have to trash a register, so we assume that any control
- transfer more than 21-bits away must be a function call
- (so we can use a call-clobbered register). */
-
- /* MOVT D0Re0,#HI(v) */
- tramp[0] = 0x02000005 | (((val & 0xffff0000) >> 16) << 3);
- /* JUMP D0Re0,#LO(v) */
- tramp[1] = 0xac000001 | ((val & 0x0000ffff) << 3);
-
- /* Init, or core PLT? */
- if (location >= mod->core_layout.base
- && location < mod->core_layout.base + mod->core_layout.size)
- entry = (void *)sechdrs[mod->arch.core_plt_section].sh_addr;
- else
- entry = (void *)sechdrs[mod->arch.init_plt_section].sh_addr;
-
- /* Find this entry, or if that fails, the next avail. entry */
- while (entry->tramp[0])
- if (entry->tramp[0] == tramp[0] && entry->tramp[1] == tramp[1])
- return (uint32_t)entry;
- else
- entry++;
-
- entry->tramp[0] = tramp[0];
- entry->tramp[1] = tramp[1];
-
- return (uint32_t)entry;
-}
-
-int apply_relocate_add(Elf32_Shdr *sechdrs,
- const char *strtab,
- unsigned int symindex,
- unsigned int relsec,
- struct module *me)
-{
- unsigned int i;
- Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
- Elf32_Sym *sym;
- Elf32_Addr relocation;
- uint32_t *location;
- int32_t value;
-
- pr_debug("Applying relocate section %u to %u\n", relsec,
- sechdrs[relsec].sh_info);
- for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
- /* This is where to make the change */
- location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
- + rel[i].r_offset;
- /* This is the symbol it is referring to. Note that all
- undefined symbols have been resolved. */
- sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
- + ELF32_R_SYM(rel[i].r_info);
- relocation = sym->st_value + rel[i].r_addend;
-
- switch (ELF32_R_TYPE(rel[i].r_info)) {
- case R_METAG_NONE:
- break;
- case R_METAG_HIADDR16:
- relocation >>= 16;
- case R_METAG_LOADDR16:
- *location = (*location & 0xfff80007) |
- ((relocation & 0xffff) << 3);
- break;
- case R_METAG_ADDR32:
- /*
- * Packed data structures may cause a misaligned
- * R_METAG_ADDR32 to be emitted.
- */
- put_unaligned(relocation, location);
- break;
- case R_METAG_GETSETOFF:
- *location += ((relocation & 0xfff) << 7);
- break;
- case R_METAG_RELBRANCH:
- if (*location & (0x7ffff << 5)) {
- pr_err("bad relbranch relocation\n");
- break;
- }
-
- /* This jump is too big for the offset slot. Build
- * a PLT to jump through to get to where we want to go.
- * NB: 21bit check - not scaled to 19bit yet
- */
- if (((int32_t)(relocation -
- (uint32_t)location) > 0xfffff) ||
- ((int32_t)(relocation -
- (uint32_t)location) < -0xfffff)) {
- relocation = do_plt_call(location, relocation,
- sechdrs, me);
- }
-
- value = relocation - (uint32_t)location;
-
- /* branch instruction aligned */
- value /= 4;
-
- if ((value > 0x7ffff) || (value < -0x7ffff)) {
- /*
- * this should have been caught by the code
- * above!
- */
- pr_err("overflow of relbranch reloc\n");
- }
-
- *location = (*location & (~(0x7ffff << 5))) |
- ((value & 0x7ffff) << 5);
- break;
-
- default:
- pr_err("module %s: Unknown relocation: %u\n",
- me->name, ELF32_R_TYPE(rel[i].r_info));
- return -ENOEXEC;
- }
- }
- return 0;
-}
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