Initial import

1 files changed, 366 insertions, 0 deletions

diff --git a/arch/arm/kernel/module.c b/arch/arm/kernel/module.c
new file mode 100644
index 000000000..af791f4a6
--- /dev/null
+++ b/arch/arm/kernel/module.c
@@ -0,0 +1,366 @@
+/*
+ *  linux/arch/arm/kernel/module.c
+ *
+ *  Copyright (C) 2002 Russell King.
+ *  Modified for nommu by Hyok S. Choi
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Module allocation method suggested by Andi Kleen.
+ */
+#include <linux/module.h>
+#include <linux/moduleloader.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/elf.h>
+#include <linux/vmalloc.h>
+#include <linux/fs.h>
+#include <linux/string.h>
+#include <linux/gfp.h>
+
+#include <asm/pgtable.h>
+#include <asm/sections.h>
+#include <asm/smp_plat.h>
+#include <asm/unwind.h>
+#include <asm/opcodes.h>
+
+#ifdef CONFIG_XIP_KERNEL
+/*
+ * The XIP kernel text is mapped in the module area for modules and
+ * some other stuff to work without any indirect relocations.
+ * MODULES_VADDR is redefined here and not in asm/memory.h to avoid
+ * recompiling the whole kernel when CONFIG_XIP_KERNEL is turned on/off.
+ */
+#undef MODULES_VADDR
+#define MODULES_VADDR	(((unsigned long)_etext + ~PMD_MASK) & PMD_MASK)
+#endif
+
+#ifdef CONFIG_MMU
+void *module_alloc(unsigned long size)
+{
+	return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
+				GFP_KERNEL, PAGE_KERNEL_EXEC, 0, NUMA_NO_NODE,
+				__builtin_return_address(0));
+}
+#endif
+
+int
+apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex,
+	       unsigned int relindex, struct module *module)
+{
+	Elf32_Shdr *symsec = sechdrs + symindex;
+	Elf32_Shdr *relsec = sechdrs + relindex;
+	Elf32_Shdr *dstsec = sechdrs + relsec->sh_info;
+	Elf32_Rel *rel = (void *)relsec->sh_addr;
+	unsigned int i;
+
+	for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++, rel++) {
+		unsigned long loc;
+		Elf32_Sym *sym;
+		const char *symname;
+		s32 offset;
+		u32 tmp;
+#ifdef CONFIG_THUMB2_KERNEL
+		u32 upper, lower, sign, j1, j2;
+#endif
+
+		offset = ELF32_R_SYM(rel->r_info);
+		if (offset < 0 || offset > (symsec->sh_size / sizeof(Elf32_Sym))) {
+			pr_err("%s: section %u reloc %u: bad relocation sym offset\n",
+				module->name, relindex, i);
+			return -ENOEXEC;
+		}
+
+		sym = ((Elf32_Sym *)symsec->sh_addr) + offset;
+		symname = strtab + sym->st_name;
+
+		if (rel->r_offset < 0 || rel->r_offset > dstsec->sh_size - sizeof(u32)) {
+			pr_err("%s: section %u reloc %u sym '%s': out of bounds relocation, offset %d size %u\n",
+			       module->name, relindex, i, symname,
+			       rel->r_offset, dstsec->sh_size);
+			return -ENOEXEC;
+		}
+
+		loc = dstsec->sh_addr + rel->r_offset;
+
+		switch (ELF32_R_TYPE(rel->r_info)) {
+		case R_ARM_NONE:
+			/* ignore */
+			break;
+
+		case R_ARM_ABS32:
+		case R_ARM_TARGET1:
+			*(u32 *)loc += sym->st_value;
+			break;
+
+		case R_ARM_PC24:
+		case R_ARM_CALL:
+		case R_ARM_JUMP24:
+			if (sym->st_value & 3) {
+				pr_err("%s: section %u reloc %u sym '%s': unsupported interworking call (ARM -> Thumb)\n",
+				       module->name, relindex, i, symname);
+				return -ENOEXEC;
+			}
+
+			offset = __mem_to_opcode_arm(*(u32 *)loc);
+			offset = (offset & 0x00ffffff) << 2;
+			if (offset & 0x02000000)
+				offset -= 0x04000000;
+
+			offset += sym->st_value - loc;
+			if (offset <= (s32)0xfe000000 ||
+			    offset >= (s32)0x02000000) {
+				pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
+				       module->name, relindex, i, symname,
+				       ELF32_R_TYPE(rel->r_info), loc,
+				       sym->st_value);
+				return -ENOEXEC;
+			}
+
+			offset >>= 2;
+			offset &= 0x00ffffff;
+
+			*(u32 *)loc &= __opcode_to_mem_arm(0xff000000);
+			*(u32 *)loc |= __opcode_to_mem_arm(offset);
+			break;
+
+	       case R_ARM_V4BX:
+		       /* Preserve Rm and the condition code. Alter
+			* other bits to re-code instruction as
+			* MOV PC,Rm.
+			*/
+		       *(u32 *)loc &= __opcode_to_mem_arm(0xf000000f);
+		       *(u32 *)loc |= __opcode_to_mem_arm(0x01a0f000);
+		       break;
+
+		case R_ARM_PREL31:
+			offset = *(u32 *)loc + sym->st_value - loc;
+			*(u32 *)loc = offset & 0x7fffffff;
+			break;
+
+		case R_ARM_MOVW_ABS_NC:
+		case R_ARM_MOVT_ABS:
+			offset = tmp = __mem_to_opcode_arm(*(u32 *)loc);
+			offset = ((offset & 0xf0000) >> 4) | (offset & 0xfff);
+			offset = (offset ^ 0x8000) - 0x8000;
+
+			offset += sym->st_value;
+			if (ELF32_R_TYPE(rel->r_info) == R_ARM_MOVT_ABS)
+				offset >>= 16;
+
+			tmp &= 0xfff0f000;
+			tmp |= ((offset & 0xf000) << 4) |
+				(offset & 0x0fff);
+
+			*(u32 *)loc = __opcode_to_mem_arm(tmp);
+			break;
+
+#ifdef CONFIG_THUMB2_KERNEL
+		case R_ARM_THM_CALL:
+		case R_ARM_THM_JUMP24:
+			/*
+			 * For function symbols, only Thumb addresses are
+			 * allowed (no interworking).
+			 *
+			 * For non-function symbols, the destination
+			 * has no specific ARM/Thumb disposition, so
+			 * the branch is resolved under the assumption
+			 * that interworking is not required.
+			 */
+			if (ELF32_ST_TYPE(sym->st_info) == STT_FUNC &&
+			    !(sym->st_value & 1)) {
+				pr_err("%s: section %u reloc %u sym '%s': unsupported interworking call (Thumb -> ARM)\n",
+				       module->name, relindex, i, symname);
+				return -ENOEXEC;
+			}
+
+			upper = __mem_to_opcode_thumb16(*(u16 *)loc);
+			lower = __mem_to_opcode_thumb16(*(u16 *)(loc + 2));
+
+			/*
+			 * 25 bit signed address range (Thumb-2 BL and B.W
+			 * instructions):
+			 *   S:I1:I2:imm10:imm11:0
+			 * where:
+			 *   S     = upper[10]   = offset[24]
+			 *   I1    = ~(J1 ^ S)   = offset[23]
+			 *   I2    = ~(J2 ^ S)   = offset[22]
+			 *   imm10 = upper[9:0]  = offset[21:12]
+			 *   imm11 = lower[10:0] = offset[11:1]
+			 *   J1    = lower[13]
+			 *   J2    = lower[11]
+			 */
+			sign = (upper >> 10) & 1;
+			j1 = (lower >> 13) & 1;
+			j2 = (lower >> 11) & 1;
+			offset = (sign << 24) | ((~(j1 ^ sign) & 1) << 23) |
+				((~(j2 ^ sign) & 1) << 22) |
+				((upper & 0x03ff) << 12) |
+				((lower & 0x07ff) << 1);
+			if (offset & 0x01000000)
+				offset -= 0x02000000;
+			offset += sym->st_value - loc;
+
+			if (offset <= (s32)0xff000000 ||
+			    offset >= (s32)0x01000000) {
+				pr_err("%s: section %u reloc %u sym '%s': relocation %u out of range (%#lx -> %#x)\n",
+				       module->name, relindex, i, symname,
+				       ELF32_R_TYPE(rel->r_info), loc,
+				       sym->st_value);
+				return -ENOEXEC;
+			}
+
+			sign = (offset >> 24) & 1;
+			j1 = sign ^ (~(offset >> 23) & 1);
+			j2 = sign ^ (~(offset >> 22) & 1);
+			upper = (u16)((upper & 0xf800) | (sign << 10) |
+					    ((offset >> 12) & 0x03ff));
+			lower = (u16)((lower & 0xd000) |
+				      (j1 << 13) | (j2 << 11) |
+				      ((offset >> 1) & 0x07ff));
+
+			*(u16 *)loc = __opcode_to_mem_thumb16(upper);
+			*(u16 *)(loc + 2) = __opcode_to_mem_thumb16(lower);
+			break;
+
+		case R_ARM_THM_MOVW_ABS_NC:
+		case R_ARM_THM_MOVT_ABS:
+			upper = __mem_to_opcode_thumb16(*(u16 *)loc);
+			lower = __mem_to_opcode_thumb16(*(u16 *)(loc + 2));
+
+			/*
+			 * MOVT/MOVW instructions encoding in Thumb-2:
+			 *
+			 * i	= upper[10]
+			 * imm4	= upper[3:0]
+			 * imm3	= lower[14:12]
+			 * imm8	= lower[7:0]
+			 *
+			 * imm16 = imm4:i:imm3:imm8
+			 */
+			offset = ((upper & 0x000f) << 12) |
+				((upper & 0x0400) << 1) |
+				((lower & 0x7000) >> 4) | (lower & 0x00ff);
+			offset = (offset ^ 0x8000) - 0x8000;
+			offset += sym->st_value;
+
+			if (ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVT_ABS)
+				offset >>= 16;
+
+			upper = (u16)((upper & 0xfbf0) |
+				      ((offset & 0xf000) >> 12) |
+				      ((offset & 0x0800) >> 1));
+			lower = (u16)((lower & 0x8f00) |
+				      ((offset & 0x0700) << 4) |
+				      (offset & 0x00ff));
+			*(u16 *)loc = __opcode_to_mem_thumb16(upper);
+			*(u16 *)(loc + 2) = __opcode_to_mem_thumb16(lower);
+			break;
+#endif
+
+		default:
+			pr_err("%s: unknown relocation: %u\n",
+			       module->name, ELF32_R_TYPE(rel->r_info));
+			return -ENOEXEC;
+		}
+	}
+	return 0;
+}
+
+struct mod_unwind_map {
+	const Elf_Shdr *unw_sec;
+	const Elf_Shdr *txt_sec;
+};
+
+static const Elf_Shdr *find_mod_section(const Elf32_Ehdr *hdr,
+	const Elf_Shdr *sechdrs, const char *name)
+{
+	const Elf_Shdr *s, *se;
+	const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
+
+	for (s = sechdrs, se = sechdrs + hdr->e_shnum; s < se; s++)
+		if (strcmp(name, secstrs + s->sh_name) == 0)
+			return s;
+
+	return NULL;
+}
+
+extern void fixup_pv_table(const void *, unsigned long);
+extern void fixup_smp(const void *, unsigned long);
+
+int module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
+		    struct module *mod)
+{
+	const Elf_Shdr *s = NULL;
+#ifdef CONFIG_ARM_UNWIND
+	const char *secstrs = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
+	const Elf_Shdr *sechdrs_end = sechdrs + hdr->e_shnum;
+	struct mod_unwind_map maps[ARM_SEC_MAX];
+	int i;
+
+	memset(maps, 0, sizeof(maps));
+
+	for (s = sechdrs; s < sechdrs_end; s++) {
+		const char *secname = secstrs + s->sh_name;
+
+		if (!(s->sh_flags & SHF_ALLOC))
+			continue;
+
+		if (strcmp(".ARM.exidx.init.text", secname) == 0)
+			maps[ARM_SEC_INIT].unw_sec = s;
+		else if (strcmp(".ARM.exidx", secname) == 0)
+			maps[ARM_SEC_CORE].unw_sec = s;
+		else if (strcmp(".ARM.exidx.exit.text", secname) == 0)
+			maps[ARM_SEC_EXIT].unw_sec = s;
+		else if (strcmp(".ARM.exidx.text.unlikely", secname) == 0)
+			maps[ARM_SEC_UNLIKELY].unw_sec = s;
+		else if (strcmp(".ARM.exidx.text.hot", secname) == 0)
+			maps[ARM_SEC_HOT].unw_sec = s;
+		else if (strcmp(".init.text", secname) == 0)
+			maps[ARM_SEC_INIT].txt_sec = s;
+		else if (strcmp(".text", secname) == 0)
+			maps[ARM_SEC_CORE].txt_sec = s;
+		else if (strcmp(".exit.text", secname) == 0)
+			maps[ARM_SEC_EXIT].txt_sec = s;
+		else if (strcmp(".text.unlikely", secname) == 0)
+			maps[ARM_SEC_UNLIKELY].txt_sec = s;
+		else if (strcmp(".text.hot", secname) == 0)
+			maps[ARM_SEC_HOT].txt_sec = s;
+	}
+
+	for (i = 0; i < ARM_SEC_MAX; i++)
+		if (maps[i].unw_sec && maps[i].txt_sec)
+			mod->arch.unwind[i] =
+				unwind_table_add(maps[i].unw_sec->sh_addr,
+					         maps[i].unw_sec->sh_size,
+					         maps[i].txt_sec->sh_addr,
+					         maps[i].txt_sec->sh_size);
+#endif
+#ifdef CONFIG_ARM_PATCH_PHYS_VIRT
+	s = find_mod_section(hdr, sechdrs, ".pv_table");
+	if (s)
+		fixup_pv_table((void *)s->sh_addr, s->sh_size);
+#endif
+	s = find_mod_section(hdr, sechdrs, ".alt.smp.init");
+	if (s && !is_smp())
+#ifdef CONFIG_SMP_ON_UP
+		fixup_smp((void *)s->sh_addr, s->sh_size);
+#else
+		return -EINVAL;
+#endif
+	return 0;
+}
+
+void
+module_arch_cleanup(struct module *mod)
+{
+#ifdef CONFIG_ARM_UNWIND
+	int i;
+
+	for (i = 0; i < ARM_SEC_MAX; i++)
+		if (mod->arch.unwind[i])
+			unwind_table_del(mod->arch.unwind[i]);
+#endif
+}