summaryrefslogtreecommitdiffstats
path: root/arch/s390/kernel/module.c
diff options
context:
space:
mode:
authorAnton Arapov <anton@redhat.com>2012-04-16 10:05:28 +0200
committerAnton Arapov <anton@redhat.com>2012-04-16 10:05:28 +0200
commitb4b6116a13633898cf868f2f103c96a90c4c20f8 (patch)
tree93d1b7e2cfcdf473d8d4ff3ad141fa864f8491f6 /arch/s390/kernel/module.c
parentedd4be777c953e5faafc80d091d3084b4343f5d3 (diff)
downloadkernel-uprobes-b4b6116a13633898cf868f2f103c96a90c4c20f8.tar.gz
kernel-uprobes-b4b6116a13633898cf868f2f103c96a90c4c20f8.tar.xz
kernel-uprobes-b4b6116a13633898cf868f2f103c96a90c4c20f8.zip
fedora kernel: d9aad82f3319f3cfd1aebc01234254ef0c37ad84v3.3.2-1
Signed-off-by: Anton Arapov <anton@redhat.com>
Diffstat (limited to 'arch/s390/kernel/module.c')
-rw-r--r--arch/s390/kernel/module.c395
1 files changed, 395 insertions, 0 deletions
diff --git a/arch/s390/kernel/module.c b/arch/s390/kernel/module.c
new file mode 100644
index 00000000000..dfcb3436bad
--- /dev/null
+++ b/arch/s390/kernel/module.c
@@ -0,0 +1,395 @@
+/*
+ * arch/s390/kernel/module.c - Kernel module help for s390.
+ *
+ * S390 version
+ * Copyright (C) 2002, 2003 IBM Deutschland Entwicklung GmbH,
+ * IBM Corporation
+ * Author(s): Arnd Bergmann (arndb@de.ibm.com)
+ * Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *
+ * based on i386 version
+ * Copyright (C) 2001 Rusty Russell.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+#include <linux/module.h>
+#include <linux/elf.h>
+#include <linux/vmalloc.h>
+#include <linux/fs.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/moduleloader.h>
+#include <linux/bug.h>
+
+#if 0
+#define DEBUGP printk
+#else
+#define DEBUGP(fmt , ...)
+#endif
+
+#ifndef CONFIG_64BIT
+#define PLT_ENTRY_SIZE 12
+#else /* CONFIG_64BIT */
+#define PLT_ENTRY_SIZE 20
+#endif /* CONFIG_64BIT */
+
+/* Free memory returned from module_alloc */
+void module_free(struct module *mod, void *module_region)
+{
+ if (mod) {
+ vfree(mod->arch.syminfo);
+ mod->arch.syminfo = NULL;
+ }
+ vfree(module_region);
+}
+
+static void
+check_rela(Elf_Rela *rela, struct module *me)
+{
+ struct mod_arch_syminfo *info;
+
+ info = me->arch.syminfo + ELF_R_SYM (rela->r_info);
+ switch (ELF_R_TYPE (rela->r_info)) {
+ case R_390_GOT12: /* 12 bit GOT offset. */
+ case R_390_GOT16: /* 16 bit GOT offset. */
+ case R_390_GOT20: /* 20 bit GOT offset. */
+ case R_390_GOT32: /* 32 bit GOT offset. */
+ case R_390_GOT64: /* 64 bit GOT offset. */
+ case R_390_GOTENT: /* 32 bit PC rel. to GOT entry shifted by 1. */
+ case R_390_GOTPLT12: /* 12 bit offset to jump slot. */
+ case R_390_GOTPLT16: /* 16 bit offset to jump slot. */
+ case R_390_GOTPLT20: /* 20 bit offset to jump slot. */
+ case R_390_GOTPLT32: /* 32 bit offset to jump slot. */
+ case R_390_GOTPLT64: /* 64 bit offset to jump slot. */
+ case R_390_GOTPLTENT: /* 32 bit rel. offset to jump slot >> 1. */
+ if (info->got_offset == -1UL) {
+ info->got_offset = me->arch.got_size;
+ me->arch.got_size += sizeof(void*);
+ }
+ break;
+ case R_390_PLT16DBL: /* 16 bit PC rel. PLT shifted by 1. */
+ case R_390_PLT32DBL: /* 32 bit PC rel. PLT shifted by 1. */
+ case R_390_PLT32: /* 32 bit PC relative PLT address. */
+ case R_390_PLT64: /* 64 bit PC relative PLT address. */
+ case R_390_PLTOFF16: /* 16 bit offset from GOT to PLT. */
+ case R_390_PLTOFF32: /* 32 bit offset from GOT to PLT. */
+ case R_390_PLTOFF64: /* 16 bit offset from GOT to PLT. */
+ if (info->plt_offset == -1UL) {
+ info->plt_offset = me->arch.plt_size;
+ me->arch.plt_size += PLT_ENTRY_SIZE;
+ }
+ break;
+ case R_390_COPY:
+ case R_390_GLOB_DAT:
+ case R_390_JMP_SLOT:
+ case R_390_RELATIVE:
+ /* Only needed if we want to support loading of
+ modules linked with -shared. */
+ break;
+ }
+}
+
+/*
+ * Account for GOT and PLT relocations. We can't add sections for
+ * got and plt but we can increase the core module size.
+ */
+int
+module_frob_arch_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
+ char *secstrings, struct module *me)
+{
+ Elf_Shdr *symtab;
+ Elf_Sym *symbols;
+ Elf_Rela *rela;
+ char *strings;
+ int nrela, i, j;
+
+ /* Find symbol table and string table. */
+ symtab = NULL;
+ for (i = 0; i < hdr->e_shnum; i++)
+ switch (sechdrs[i].sh_type) {
+ case SHT_SYMTAB:
+ symtab = sechdrs + i;
+ break;
+ }
+ if (!symtab) {
+ printk(KERN_ERR "module %s: no symbol table\n", me->name);
+ return -ENOEXEC;
+ }
+
+ /* Allocate one syminfo structure per symbol. */
+ me->arch.nsyms = symtab->sh_size / sizeof(Elf_Sym);
+ me->arch.syminfo = vmalloc(me->arch.nsyms *
+ sizeof(struct mod_arch_syminfo));
+ if (!me->arch.syminfo)
+ return -ENOMEM;
+ symbols = (void *) hdr + symtab->sh_offset;
+ strings = (void *) hdr + sechdrs[symtab->sh_link].sh_offset;
+ for (i = 0; i < me->arch.nsyms; i++) {
+ if (symbols[i].st_shndx == SHN_UNDEF &&
+ strcmp(strings + symbols[i].st_name,
+ "_GLOBAL_OFFSET_TABLE_") == 0)
+ /* "Define" it as absolute. */
+ symbols[i].st_shndx = SHN_ABS;
+ me->arch.syminfo[i].got_offset = -1UL;
+ me->arch.syminfo[i].plt_offset = -1UL;
+ me->arch.syminfo[i].got_initialized = 0;
+ me->arch.syminfo[i].plt_initialized = 0;
+ }
+
+ /* Search for got/plt relocations. */
+ me->arch.got_size = me->arch.plt_size = 0;
+ for (i = 0; i < hdr->e_shnum; i++) {
+ if (sechdrs[i].sh_type != SHT_RELA)
+ continue;
+ nrela = sechdrs[i].sh_size / sizeof(Elf_Rela);
+ rela = (void *) hdr + sechdrs[i].sh_offset;
+ for (j = 0; j < nrela; j++)
+ check_rela(rela + j, me);
+ }
+
+ /* Increase core size by size of got & plt and set start
+ offsets for got and plt. */
+ me->core_size = ALIGN(me->core_size, 4);
+ me->arch.got_offset = me->core_size;
+ me->core_size += me->arch.got_size;
+ me->arch.plt_offset = me->core_size;
+ me->core_size += me->arch.plt_size;
+ return 0;
+}
+
+static int
+apply_rela(Elf_Rela *rela, Elf_Addr base, Elf_Sym *symtab,
+ struct module *me)
+{
+ struct mod_arch_syminfo *info;
+ Elf_Addr loc, val;
+ int r_type, r_sym;
+
+ /* This is where to make the change */
+ loc = base + rela->r_offset;
+ /* This is the symbol it is referring to. Note that all
+ undefined symbols have been resolved. */
+ r_sym = ELF_R_SYM(rela->r_info);
+ r_type = ELF_R_TYPE(rela->r_info);
+ info = me->arch.syminfo + r_sym;
+ val = symtab[r_sym].st_value;
+
+ switch (r_type) {
+ case R_390_8: /* Direct 8 bit. */
+ case R_390_12: /* Direct 12 bit. */
+ case R_390_16: /* Direct 16 bit. */
+ case R_390_20: /* Direct 20 bit. */
+ case R_390_32: /* Direct 32 bit. */
+ case R_390_64: /* Direct 64 bit. */
+ val += rela->r_addend;
+ if (r_type == R_390_8)
+ *(unsigned char *) loc = val;
+ else if (r_type == R_390_12)
+ *(unsigned short *) loc = (val & 0xfff) |
+ (*(unsigned short *) loc & 0xf000);
+ else if (r_type == R_390_16)
+ *(unsigned short *) loc = val;
+ else if (r_type == R_390_20)
+ *(unsigned int *) loc =
+ (*(unsigned int *) loc & 0xf00000ff) |
+ (val & 0xfff) << 16 | (val & 0xff000) >> 4;
+ else if (r_type == R_390_32)
+ *(unsigned int *) loc = val;
+ else if (r_type == R_390_64)
+ *(unsigned long *) loc = val;
+ break;
+ case R_390_PC16: /* PC relative 16 bit. */
+ case R_390_PC16DBL: /* PC relative 16 bit shifted by 1. */
+ case R_390_PC32DBL: /* PC relative 32 bit shifted by 1. */
+ case R_390_PC32: /* PC relative 32 bit. */
+ case R_390_PC64: /* PC relative 64 bit. */
+ val += rela->r_addend - loc;
+ if (r_type == R_390_PC16)
+ *(unsigned short *) loc = val;
+ else if (r_type == R_390_PC16DBL)
+ *(unsigned short *) loc = val >> 1;
+ else if (r_type == R_390_PC32DBL)
+ *(unsigned int *) loc = val >> 1;
+ else if (r_type == R_390_PC32)
+ *(unsigned int *) loc = val;
+ else if (r_type == R_390_PC64)
+ *(unsigned long *) loc = val;
+ break;
+ case R_390_GOT12: /* 12 bit GOT offset. */
+ case R_390_GOT16: /* 16 bit GOT offset. */
+ case R_390_GOT20: /* 20 bit GOT offset. */
+ case R_390_GOT32: /* 32 bit GOT offset. */
+ case R_390_GOT64: /* 64 bit GOT offset. */
+ case R_390_GOTENT: /* 32 bit PC rel. to GOT entry shifted by 1. */
+ case R_390_GOTPLT12: /* 12 bit offset to jump slot. */
+ case R_390_GOTPLT20: /* 20 bit offset to jump slot. */
+ case R_390_GOTPLT16: /* 16 bit offset to jump slot. */
+ case R_390_GOTPLT32: /* 32 bit offset to jump slot. */
+ case R_390_GOTPLT64: /* 64 bit offset to jump slot. */
+ case R_390_GOTPLTENT: /* 32 bit rel. offset to jump slot >> 1. */
+ if (info->got_initialized == 0) {
+ Elf_Addr *gotent;
+
+ gotent = me->module_core + me->arch.got_offset +
+ info->got_offset;
+ *gotent = val;
+ info->got_initialized = 1;
+ }
+ val = info->got_offset + rela->r_addend;
+ if (r_type == R_390_GOT12 ||
+ r_type == R_390_GOTPLT12)
+ *(unsigned short *) loc = (val & 0xfff) |
+ (*(unsigned short *) loc & 0xf000);
+ else if (r_type == R_390_GOT16 ||
+ r_type == R_390_GOTPLT16)
+ *(unsigned short *) loc = val;
+ else if (r_type == R_390_GOT20 ||
+ r_type == R_390_GOTPLT20)
+ *(unsigned int *) loc =
+ (*(unsigned int *) loc & 0xf00000ff) |
+ (val & 0xfff) << 16 | (val & 0xff000) >> 4;
+ else if (r_type == R_390_GOT32 ||
+ r_type == R_390_GOTPLT32)
+ *(unsigned int *) loc = val;
+ else if (r_type == R_390_GOTENT ||
+ r_type == R_390_GOTPLTENT)
+ *(unsigned int *) loc =
+ (val + (Elf_Addr) me->module_core - loc) >> 1;
+ else if (r_type == R_390_GOT64 ||
+ r_type == R_390_GOTPLT64)
+ *(unsigned long *) loc = val;
+ break;
+ case R_390_PLT16DBL: /* 16 bit PC rel. PLT shifted by 1. */
+ case R_390_PLT32DBL: /* 32 bit PC rel. PLT shifted by 1. */
+ case R_390_PLT32: /* 32 bit PC relative PLT address. */
+ case R_390_PLT64: /* 64 bit PC relative PLT address. */
+ case R_390_PLTOFF16: /* 16 bit offset from GOT to PLT. */
+ case R_390_PLTOFF32: /* 32 bit offset from GOT to PLT. */
+ case R_390_PLTOFF64: /* 16 bit offset from GOT to PLT. */
+ if (info->plt_initialized == 0) {
+ unsigned int *ip;
+ ip = me->module_core + me->arch.plt_offset +
+ info->plt_offset;
+#ifndef CONFIG_64BIT
+ ip[0] = 0x0d105810; /* basr 1,0; l 1,6(1); br 1 */
+ ip[1] = 0x100607f1;
+ ip[2] = val;
+#else /* CONFIG_64BIT */
+ ip[0] = 0x0d10e310; /* basr 1,0; lg 1,10(1); br 1 */
+ ip[1] = 0x100a0004;
+ ip[2] = 0x07f10000;
+ ip[3] = (unsigned int) (val >> 32);
+ ip[4] = (unsigned int) val;
+#endif /* CONFIG_64BIT */
+ info->plt_initialized = 1;
+ }
+ if (r_type == R_390_PLTOFF16 ||
+ r_type == R_390_PLTOFF32 ||
+ r_type == R_390_PLTOFF64)
+ val = me->arch.plt_offset - me->arch.got_offset +
+ info->plt_offset + rela->r_addend;
+ else {
+ if (!((r_type == R_390_PLT16DBL &&
+ val - loc + 0xffffUL < 0x1ffffeUL) ||
+ (r_type == R_390_PLT32DBL &&
+ val - loc + 0xffffffffULL < 0x1fffffffeULL)))
+ val = (Elf_Addr) me->module_core +
+ me->arch.plt_offset +
+ info->plt_offset;
+ val += rela->r_addend - loc;
+ }
+ if (r_type == R_390_PLT16DBL)
+ *(unsigned short *) loc = val >> 1;
+ else if (r_type == R_390_PLTOFF16)
+ *(unsigned short *) loc = val;
+ else if (r_type == R_390_PLT32DBL)
+ *(unsigned int *) loc = val >> 1;
+ else if (r_type == R_390_PLT32 ||
+ r_type == R_390_PLTOFF32)
+ *(unsigned int *) loc = val;
+ else if (r_type == R_390_PLT64 ||
+ r_type == R_390_PLTOFF64)
+ *(unsigned long *) loc = val;
+ break;
+ case R_390_GOTOFF16: /* 16 bit offset to GOT. */
+ case R_390_GOTOFF32: /* 32 bit offset to GOT. */
+ case R_390_GOTOFF64: /* 64 bit offset to GOT. */
+ val = val + rela->r_addend -
+ ((Elf_Addr) me->module_core + me->arch.got_offset);
+ if (r_type == R_390_GOTOFF16)
+ *(unsigned short *) loc = val;
+ else if (r_type == R_390_GOTOFF32)
+ *(unsigned int *) loc = val;
+ else if (r_type == R_390_GOTOFF64)
+ *(unsigned long *) loc = val;
+ break;
+ case R_390_GOTPC: /* 32 bit PC relative offset to GOT. */
+ case R_390_GOTPCDBL: /* 32 bit PC rel. off. to GOT shifted by 1. */
+ val = (Elf_Addr) me->module_core + me->arch.got_offset +
+ rela->r_addend - loc;
+ if (r_type == R_390_GOTPC)
+ *(unsigned int *) loc = val;
+ else if (r_type == R_390_GOTPCDBL)
+ *(unsigned int *) loc = val >> 1;
+ break;
+ case R_390_COPY:
+ case R_390_GLOB_DAT: /* Create GOT entry. */
+ case R_390_JMP_SLOT: /* Create PLT entry. */
+ case R_390_RELATIVE: /* Adjust by program base. */
+ /* Only needed if we want to support loading of
+ modules linked with -shared. */
+ break;
+ default:
+ printk(KERN_ERR "module %s: Unknown relocation: %u\n",
+ me->name, r_type);
+ return -ENOEXEC;
+ }
+ return 0;
+}
+
+int
+apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
+ unsigned int symindex, unsigned int relsec,
+ struct module *me)
+{
+ Elf_Addr base;
+ Elf_Sym *symtab;
+ Elf_Rela *rela;
+ unsigned long i, n;
+ int rc;
+
+ DEBUGP("Applying relocate section %u to %u\n",
+ relsec, sechdrs[relsec].sh_info);
+ base = sechdrs[sechdrs[relsec].sh_info].sh_addr;
+ symtab = (Elf_Sym *) sechdrs[symindex].sh_addr;
+ rela = (Elf_Rela *) sechdrs[relsec].sh_addr;
+ n = sechdrs[relsec].sh_size / sizeof(Elf_Rela);
+
+ for (i = 0; i < n; i++, rela++) {
+ rc = apply_rela(rela, base, symtab, me);
+ if (rc)
+ return rc;
+ }
+ return 0;
+}
+
+int module_finalize(const Elf_Ehdr *hdr,
+ const Elf_Shdr *sechdrs,
+ struct module *me)
+{
+ vfree(me->arch.syminfo);
+ me->arch.syminfo = NULL;
+ return 0;
+}