Applied patch from Larry Doolittle to remove some strlen calls, and add one
[oweals/busybox.git] / insmod.c
index 7af135902a9e9e49a0af0534bee265355343b076..f1798ad0927f95052c4fce51c8ab110f6d8f1a6d 100644 (file)
--- a/insmod.c
+++ b/insmod.c
  *   I've only tested the code on mpc8xx platforms in big-endian mode.
  *   Did some cleanup and added BB_USE_xxx_ENTRIES...
  *
+ * Quinn Jensen <jensenq@lineo.com> added MIPS support 23-Feb-2001.
+ *   based on modutils-2.4.2
+ *   MIPS specific support for Elf loading and relocation.
+ *   Copyright 1996, 1997 Linux International.
+ *   Contributed by Ralf Baechle <ralf@gnu.ai.mit.edu>
+ *
  * Based almost entirely on the Linux modutils-2.3.11 implementation.
  *   Copyright 1996, 1997 Linux International.
  *   New implementation contributed by Richard Henderson <rth@tamu.edu>
 #include <string.h>
 #include <getopt.h>
 #include <sys/utsname.h>
-#include <sys/syscall.h>
-#include <linux/unistd.h>
 #include "busybox.h"
 
+#ifdef BB_FEATURE_NEW_MODULE_INTERFACE
+# define new_sys_init_module   init_module
+#else
+# define old_sys_init_module   init_module
+#endif
+
 #if defined(__powerpc__)
 #define BB_USE_PLT_ENTRIES
 #define BB_PLT_ENTRY_SIZE 16
 #define BB_GOT_ENTRY_SIZE 4
 #endif
 
+#if defined(__mips__)
+// neither used
+#endif
+
 //----------------------------------------------------------------------------
 //--------modutils module.h, lines 45-242
 //----------------------------------------------------------------------------
 #ifndef MODUTILS_MODULE_H
 static const int MODUTILS_MODULE_H = 1;
 
-#ident "$Id: insmod.c,v 1.49 2001/02/20 20:47:08 andersen Exp $"
+#ident "$Id: insmod.c,v 1.57 2001/04/05 07:33:10 andersen Exp $"
 
 /* This file contains the structures used by the 2.0 and 2.1 kernels.
    We do not use the kernel headers directly because we do not wish
@@ -315,7 +329,7 @@ int delete_module(const char *);
 #ifndef MODUTILS_OBJ_H
 static const int MODUTILS_OBJ_H = 1;
 
-#ident "$Id: insmod.c,v 1.49 2001/02/20 20:47:08 andersen Exp $"
+#ident "$Id: insmod.c,v 1.57 2001/04/05 07:33:10 andersen Exp $"
 
 /* The relocatable object is manipulated using elfin types.  */
 
@@ -361,6 +375,27 @@ static const int MODUTILS_OBJ_H = 1;
 #define Elf32_RelM     Elf32_Rela
 #define ELFDATAM        ELFDATA2MSB
 
+#elif defined(__mips__)
+
+/* Account for ELF spec changes.  */
+#ifndef EM_MIPS_RS3_LE
+#ifdef EM_MIPS_RS4_BE
+#define EM_MIPS_RS3_LE EM_MIPS_RS4_BE
+#else
+#define EM_MIPS_RS3_LE 10
+#endif
+#endif /* !EM_MIPS_RS3_LE */
+
+#define MATCH_MACHINE(x) (x == EM_MIPS || x == EM_MIPS_RS3_LE)
+#define SHT_RELM       SHT_REL
+#define Elf32_RelM     Elf32_Rel
+#ifdef __MIPSEB__
+#define ELFDATAM        ELFDATA2MSB
+#endif
+#ifdef __MIPSEL__
+#define ELFDATAM        ELFDATA2LSB
+#endif
+
 #elif defined(__i386__)
 
 /* presumably we can use these for anything but the SH and ARM*/
@@ -594,6 +629,15 @@ struct arch_got_entry {
 };
 #endif
 
+#if defined(__mips__)
+struct mips_hi16
+{
+  struct mips_hi16 *next;
+  Elf32_Addr *addr;
+  Elf32_Addr value;
+};
+#endif
+
 struct arch_file {
        struct obj_file root;
 #if defined(BB_USE_PLT_ENTRIES)
@@ -602,6 +646,9 @@ struct arch_file {
 #if defined(BB_USE_GOT_ENTRIES)
        struct obj_section *got;
 #endif
+#if defined(__mips__)
+       struct mips_hi16 *mips_hi16_list;
+#endif
 };
 
 struct arch_symbol {
@@ -631,20 +678,8 @@ int n_ext_modules;
 int n_ext_modules_used;
 
 
-
-/* Some firendly syscalls to cheer everyone's day...  */
-#define __NR_new_sys_init_module  __NR_init_module
-_syscall2(int, new_sys_init_module, const char *, name,
-                 const struct new_module *, info)
-#define __NR_old_sys_init_module  __NR_init_module
-_syscall5(int, old_sys_init_module, const char *, name, char *, code,
-                 unsigned, codesize, struct old_mod_routines *, routines,
-                 struct old_symbol_table *, symtab)
-#ifndef BB_RMMOD
-_syscall1(int, delete_module, const char *, name)
-#else
 extern int delete_module(const char *);
-#endif
+
 
 /* This is kind of troublesome. See, we don't actually support
    the m68k or the arm the same way we support i386 and (now)
@@ -657,31 +692,8 @@ extern int delete_module(const char *);
 
    -- Bryan Rittmeyer <bryan@ixiacom.com>                    */
 
-#ifdef BB_FEATURE_OLD_MODULE_INTERFACE
-_syscall1(int, get_kernel_syms, struct old_kernel_sym *, ks)
-#endif
-
-#if defined(__i386__) || defined(__m68k__) || defined(__arm__) \
- || defined(__powerpc__)
-/* Jump through hoops to fixup error return codes */
-#define __NR__create_module  __NR_create_module
-static inline _syscall2(long, _create_module, const char *, name, size_t,
-                                               size)
-unsigned long create_module(const char *name, size_t size)
-{
-       long ret = _create_module(name, size);
-
-       if (ret == -1 && errno > 125) {
-               ret = -errno;
-               errno = 0;
-       }
-       return ret;
-}
-#else
-_syscall2(unsigned long, create_module, const char *, name, size_t, size)
-#endif
-static char m_filename[BUFSIZ + 1] = "\0";
-static char m_fullName[BUFSIZ + 1] = "\0";
+static char m_filename[BUFSIZ + 1];
+static char m_fullName[BUFSIZ + 1];
 
 /*======================================================================*/
 
@@ -724,6 +736,9 @@ struct obj_file *arch_new_file(void)
 #if defined(BB_USE_GOT_ENTRIES)
        f->got = NULL;
 #endif
+#if defined(__mips__)
+       f->mips_hi16_list = NULL;
+#endif
 
        return &f->root;
 }
@@ -756,7 +771,9 @@ arch_apply_relocation(struct obj_file *f,
                                      ElfW(RelM) *rel, ElfW(Addr) v)
 {
        struct arch_file *ifile = (struct arch_file *) f;
+#if !(defined(__mips__))
        struct arch_symbol *isym = (struct arch_symbol *) sym;
+#endif
 
        ElfW(Addr) *loc = (ElfW(Addr) *) (targsec->contents + rel->r_offset);
        ElfW(Addr) dot = targsec->header.sh_addr + rel->r_offset;
@@ -783,6 +800,8 @@ arch_apply_relocation(struct obj_file *f,
        case R_386_NONE:
 #elif defined(__powerpc__)
        case R_PPC_NONE:
+#elif defined(__mips__)
+       case R_MIPS_NONE:
 #endif
                break;
 
@@ -794,6 +813,8 @@ arch_apply_relocation(struct obj_file *f,
        case R_386_32:  
 #elif defined(__powerpc__)
        case R_PPC_ADDR32:
+#elif defined(__mips__)
+       case R_MIPS_32:
 #endif
                *loc += v;
                break;
@@ -812,6 +833,86 @@ arch_apply_relocation(struct obj_file *f,
                break;
 #endif
 
+#if defined(__mips__)
+       case R_MIPS_26:
+               if (v % 4)
+                       ret = obj_reloc_dangerous;
+               if ((v & 0xf0000000) != ((dot + 4) & 0xf0000000))
+                       ret = obj_reloc_overflow;
+               *loc =
+                   (*loc & ~0x03ffffff) | ((*loc + (v >> 2)) &
+                                           0x03ffffff);
+               break;
+
+       case R_MIPS_HI16:
+               {
+                       struct mips_hi16 *n;
+
+                       /* We cannot relocate this one now because we don't know the value
+                          of the carry we need to add.  Save the information, and let LO16
+                          do the actual relocation.  */
+                       n = (struct mips_hi16 *) xmalloc(sizeof *n);
+                       n->addr = loc;
+                       n->value = v;
+                       n->next = ifile->mips_hi16_list;
+                       ifile->mips_hi16_list = n;
+                       break;
+               }
+
+       case R_MIPS_LO16:
+               {
+                       unsigned long insnlo = *loc;
+                       Elf32_Addr val, vallo;
+
+                       /* Sign extend the addend we extract from the lo insn.  */
+                       vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
+
+                       if (ifile->mips_hi16_list != NULL) {
+                               struct mips_hi16 *l;
+
+                               l = ifile->mips_hi16_list;
+                               while (l != NULL) {
+                                       struct mips_hi16 *next;
+                                       unsigned long insn;
+
+                                       /* The value for the HI16 had best be the same. */
+                                       assert(v == l->value);
+
+                                       /* Do the HI16 relocation.  Note that we actually don't
+                                          need to know anything about the LO16 itself, except where
+                                          to find the low 16 bits of the addend needed by the LO16.  */
+                                       insn = *l->addr;
+                                       val =
+                                           ((insn & 0xffff) << 16) +
+                                           vallo;
+                                       val += v;
+
+                                       /* Account for the sign extension that will happen in the
+                                          low bits.  */
+                                       val =
+                                           ((val >> 16) +
+                                            ((val & 0x8000) !=
+                                             0)) & 0xffff;
+
+                                       insn = (insn & ~0xffff) | val;
+                                       *l->addr = insn;
+
+                                       next = l->next;
+                                       free(l);
+                                       l = next;
+                               }
+
+                               ifile->mips_hi16_list = NULL;
+                       }
+
+                       /* Ok, we're done with the HI16 relocs.  Now deal with the LO16.  */
+                       val = v + vallo;
+                       insnlo = (insnlo & ~0xffff) | (val & 0xffff);
+                       *loc = insnlo;
+                       break;
+               }
+#endif
+
 #if defined(__arm__)
 #elif defined(__sh__)
         case R_SH_REL32:
@@ -977,6 +1078,7 @@ arch_apply_relocation(struct obj_file *f,
 
 int arch_create_got(struct obj_file *f)
 {
+#if defined(BB_USE_GOT_ENTRIES) || defined(BB_USE_PLT_ENTRIES)
        struct arch_file *ifile = (struct arch_file *) f;
        int i;
 #if defined(BB_USE_GOT_ENTRIES)
@@ -1077,18 +1179,18 @@ int arch_create_got(struct obj_file *f)
 
 #if defined(BB_USE_GOT_ENTRIES)
        if (got_offset) {
-               struct obj_section* relsec = obj_find_section(f, ".got");
+               struct obj_section* myrelsec = obj_find_section(f, ".got");
 
-               if (relsec) {
-                       obj_extend_section(relsec, got_offset);
+               if (myrelsec) {
+                       obj_extend_section(myrelsec, got_offset);
                } else {
-                       relsec = obj_create_alloced_section(f, ".got", 
+                       myrelsec = obj_create_alloced_section(f, ".got", 
                                                            BB_GOT_ENTRY_SIZE,
                                                            got_offset);
-                       assert(relsec);
+                       assert(myrelsec);
                }
 
-               ifile->got = relsec;
+               ifile->got = myrelsec;
        }
 #endif
 
@@ -1097,6 +1199,7 @@ int arch_create_got(struct obj_file *f)
                ifile->plt = obj_create_alloced_section(f, ".plt", 
                                                        BB_PLT_ENTRY_SIZE, 
                                                        plt_offset);
+#endif
 #endif
        return 1;
 }
@@ -1614,19 +1717,19 @@ old_process_module_arguments(struct obj_file *f, int argc, char **argv)
                        while (*q++ == ',');
                } else {
                        char *contents = f->sections[sym->secidx]->contents;
-                       char *loc = contents + sym->value;
+                       char *myloc = contents + sym->value;
                        char *r;                        /* To search for commas */
 
                        /* Break the string with comas */
                        while ((r = strchr(q, ',')) != (char *) NULL) {
                                *r++ = '\0';
-                               obj_string_patch(f, sym->secidx, loc - contents, q);
-                               loc += sizeof(char *);
+                               obj_string_patch(f, sym->secidx, myloc - contents, q);
+                               myloc += sizeof(char *);
                                q = r;
                        }
 
                        /* last part */
-                       obj_string_patch(f, sym->secidx, loc - contents, q);
+                       obj_string_patch(f, sym->secidx, myloc - contents, q);
                }
 
                argc--, argv++;
@@ -2183,48 +2286,50 @@ static int new_get_kernel_symbols(void)
        }
 
        n_ext_modules = nmod = ret;
-       ext_modules = modules = xmalloc(nmod * sizeof(*modules));
-       memset(modules, 0, nmod * sizeof(*modules));
 
        /* Collect the modules' symbols.  */
 
-       for (i = 0, mn = module_names, m = modules;
-                i < nmod; ++i, ++m, mn += strlen(mn) + 1) {
-               struct new_module_info info;
-
-               if (query_module(mn, QM_INFO, &info, sizeof(info), &ret)) {
-                       if (errno == ENOENT) {
-                               /* The module was removed out from underneath us.  */
-                               continue;
-                       }
-                       perror_msg("query_module: QM_INFO: %s", mn);
-                       return 0;
-               }
-
-               syms = xmalloc(bufsize = 1024);
-         retry_mod_sym_load:
-               if (query_module(mn, QM_SYMBOLS, syms, bufsize, &ret)) {
-                       switch (errno) {
-                       case ENOSPC:
-                               syms = xrealloc(syms, bufsize = ret);
-                               goto retry_mod_sym_load;
-                       case ENOENT:
-                               /* The module was removed out from underneath us.  */
-                               continue;
-                       default:
-                               perror_msg("query_module: QM_SYMBOLS: %s", mn);
+       if (nmod){
+               ext_modules = modules = xmalloc(nmod * sizeof(*modules));
+               memset(modules, 0, nmod * sizeof(*modules));
+               for (i = 0, mn = module_names, m = modules;
+                        i < nmod; ++i, ++m, mn += strlen(mn) + 1) {
+                       struct new_module_info info;
+       
+                       if (query_module(mn, QM_INFO, &info, sizeof(info), &ret)) {
+                               if (errno == ENOENT) {
+                                       /* The module was removed out from underneath us.  */
+                                       continue;
+                               }
+                               perror_msg("query_module: QM_INFO: %s", mn);
                                return 0;
                        }
-               }
-               nsyms = ret;
-
-               m->name = mn;
-               m->addr = info.addr;
-               m->nsyms = nsyms;
-               m->syms = syms;
-
-               for (j = 0, s = syms; j < nsyms; ++j, ++s) {
-                       s->name += (unsigned long) syms;
+       
+                       syms = xmalloc(bufsize = 1024);
+                 retry_mod_sym_load:
+                       if (query_module(mn, QM_SYMBOLS, syms, bufsize, &ret)) {
+                               switch (errno) {
+                               case ENOSPC:
+                                       syms = xrealloc(syms, bufsize = ret);
+                                       goto retry_mod_sym_load;
+                               case ENOENT:
+                                       /* The module was removed out from underneath us.  */
+                                       continue;
+                               default:
+                                       perror_msg("query_module: QM_SYMBOLS: %s", mn);
+                                       return 0;
+                               }
+                       }
+                       nsyms = ret;
+       
+                       m->name = mn;
+                       m->addr = info.addr;
+                       m->nsyms = nsyms;
+                       m->syms = syms;
+       
+                       for (j = 0, s = syms; j < nsyms; ++j, ++s) {
+                               s->name += (unsigned long) syms;
+                       }
                }
        }
 
@@ -2772,7 +2877,7 @@ int obj_create_image(struct obj_file *f, char *image)
        for (sec = f->load_order; sec; sec = sec->load_next) {
                char *secimg;
 
-               if (sec->header.sh_size == 0)
+               if (sec->contents == 0 || sec->header.sh_size == 0)
                        continue;
 
                secimg = image + (sec->header.sh_addr - base);
@@ -2857,7 +2962,7 @@ struct obj_file *obj_load(FILE * fp)
                sec->header = section_headers[i];
                sec->idx = i;
 
-               switch (sec->header.sh_type) {
+               if(sec->header.sh_size) switch (sec->header.sh_type) {
                case SHT_NULL:
                case SHT_NOTE:
                case SHT_NOBITS: