Initial import

1 files changed, 192 insertions, 0 deletions

diff --git a/arch/xtensa/kernel/module.c b/arch/xtensa/kernel/module.c
new file mode 100644
index 000000000..b715237ba
--- /dev/null
+++ b/arch/xtensa/kernel/module.c
@@ -0,0 +1,192 @@
+/*
+ * arch/xtensa/kernel/module.c
+ *
+ * Module support.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2001 - 2006 Tensilica Inc.
+ *
+ * Chris Zankel <chris@zankel.net>
+ *
+ */
+
+#include <linux/module.h>
+#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/cache.h>
+
+#undef DEBUG_RELOCATE
+
+static int
+decode_calln_opcode (unsigned char *location)
+{
+#ifdef __XTENSA_EB__
+	return (location[0] & 0xf0) == 0x50;
+#endif
+#ifdef __XTENSA_EL__
+	return (location[0] & 0xf) == 0x5;
+#endif
+}
+
+static int
+decode_l32r_opcode (unsigned char *location)
+{
+#ifdef __XTENSA_EB__
+	return (location[0] & 0xf0) == 0x10;
+#endif
+#ifdef __XTENSA_EL__
+	return (location[0] & 0xf) == 0x1;
+#endif
+}
+
+int apply_relocate_add(Elf32_Shdr *sechdrs,
+		       const char *strtab,
+		       unsigned int symindex,
+		       unsigned int relsec,
+		       struct module *mod)
+{
+	unsigned int i;
+	Elf32_Rela *rela = (void *)sechdrs[relsec].sh_addr;
+	Elf32_Sym *sym;
+	unsigned char *location;
+	uint32_t value;
+
+#ifdef DEBUG_RELOCATE
+	printk("Applying relocate section %u to %u\n", relsec,
+	       sechdrs[relsec].sh_info);
+#endif
+	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rela); i++) {
+		location = (char *)sechdrs[sechdrs[relsec].sh_info].sh_addr
+			+ rela[i].r_offset;
+		sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
+			+ ELF32_R_SYM(rela[i].r_info);
+		value = sym->st_value + rela[i].r_addend;
+
+		switch (ELF32_R_TYPE(rela[i].r_info)) {
+		case R_XTENSA_NONE:
+		case R_XTENSA_DIFF8:
+		case R_XTENSA_DIFF16:
+		case R_XTENSA_DIFF32:
+		case R_XTENSA_ASM_EXPAND:
+			break;
+
+		case R_XTENSA_32:
+		case R_XTENSA_PLT:
+			*(uint32_t *)location += value;
+			break;
+
+		case R_XTENSA_SLOT0_OP:
+			if (decode_calln_opcode(location)) {
+				value -= ((unsigned long)location & -4) + 4;
+				if ((value & 3) != 0 ||
+				    ((value + (1 << 19)) >> 20) != 0) {
+					printk("%s: relocation out of range, "
+					       "section %d reloc %d "
+					       "sym '%s'\n",
+					       mod->name, relsec, i,
+					       strtab + sym->st_name);
+					return -ENOEXEC;
+				}
+				value = (signed int)value >> 2;
+#ifdef __XTENSA_EB__
+				location[0] = ((location[0] & ~0x3) |
+					    ((value >> 16) & 0x3));
+				location[1] = (value >> 8) & 0xff;
+				location[2] = value & 0xff;
+#endif
+#ifdef __XTENSA_EL__
+				location[0] = ((location[0] & ~0xc0) |
+					    ((value << 6) & 0xc0));
+				location[1] = (value >> 2) & 0xff;
+				location[2] = (value >> 10) & 0xff;
+#endif
+			} else if (decode_l32r_opcode(location)) {
+				value -= (((unsigned long)location + 3) & -4);
+				if ((value & 3) != 0 ||
+				    (signed int)value >> 18 != -1) {
+					printk("%s: relocation out of range, "
+					       "section %d reloc %d "
+					       "sym '%s'\n",
+					       mod->name, relsec, i,
+					       strtab + sym->st_name);
+					return -ENOEXEC;
+				}
+				value = (signed int)value >> 2;
+
+#ifdef __XTENSA_EB__
+				location[1] = (value >> 8) & 0xff;
+				location[2] = value & 0xff;
+#endif
+#ifdef __XTENSA_EL__
+				location[1] = value & 0xff;
+				location[2] = (value >> 8) & 0xff;
+#endif
+			}
+			/* FIXME: Ignore any other opcodes.  The Xtensa
+			   assembler currently assumes that the linker will
+			   always do relaxation and so all PC-relative
+			   operands need relocations.  (The assembler also
+			   writes out the tentative PC-relative values,
+			   assuming no link-time relaxation, so it is usually
+			   safe to ignore the relocations.)  If the
+			   assembler's "--no-link-relax" flag can be made to
+			   work, and if all kernel modules can be assembled
+			   with that flag, then unexpected relocations could
+			   be detected here.  */
+			break;
+
+		case R_XTENSA_SLOT1_OP:
+		case R_XTENSA_SLOT2_OP:
+		case R_XTENSA_SLOT3_OP:
+		case R_XTENSA_SLOT4_OP:
+		case R_XTENSA_SLOT5_OP:
+		case R_XTENSA_SLOT6_OP:
+		case R_XTENSA_SLOT7_OP:
+		case R_XTENSA_SLOT8_OP:
+		case R_XTENSA_SLOT9_OP:
+		case R_XTENSA_SLOT10_OP:
+		case R_XTENSA_SLOT11_OP:
+		case R_XTENSA_SLOT12_OP:
+		case R_XTENSA_SLOT13_OP:
+		case R_XTENSA_SLOT14_OP:
+			printk("%s: unexpected FLIX relocation: %u\n",
+			       mod->name,
+			       ELF32_R_TYPE(rela[i].r_info));
+			return -ENOEXEC;
+
+		case R_XTENSA_SLOT0_ALT:
+		case R_XTENSA_SLOT1_ALT:
+		case R_XTENSA_SLOT2_ALT:
+		case R_XTENSA_SLOT3_ALT:
+		case R_XTENSA_SLOT4_ALT:
+		case R_XTENSA_SLOT5_ALT:
+		case R_XTENSA_SLOT6_ALT:
+		case R_XTENSA_SLOT7_ALT:
+		case R_XTENSA_SLOT8_ALT:
+		case R_XTENSA_SLOT9_ALT:
+		case R_XTENSA_SLOT10_ALT:
+		case R_XTENSA_SLOT11_ALT:
+		case R_XTENSA_SLOT12_ALT:
+		case R_XTENSA_SLOT13_ALT:
+		case R_XTENSA_SLOT14_ALT:
+			printk("%s: unexpected ALT relocation: %u\n",
+			       mod->name,
+			       ELF32_R_TYPE(rela[i].r_info));
+			return -ENOEXEC;
+
+		default:
+			printk("%s: unexpected relocation: %u\n",
+			       mod->name,
+			       ELF32_R_TYPE(rela[i].r_info));
+			return -ENOEXEC;
+		}
+	}
+	return 0;
+}