linux/arch/arm/kernel/module.c
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00

305 lines
8.2 KiB
C

/*
* 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/unwind.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 + ~PGDIR_MASK) & PGDIR_MASK)
#endif
#ifdef CONFIG_MMU
void *module_alloc(unsigned long size)
{
struct vm_struct *area;
size = PAGE_ALIGN(size);
if (!size)
return NULL;
area = __get_vm_area(size, VM_ALLOC, MODULES_VADDR, MODULES_END);
if (!area)
return NULL;
return __vmalloc_area(area, GFP_KERNEL, PAGE_KERNEL_EXEC);
}
#else /* CONFIG_MMU */
void *module_alloc(unsigned long size)
{
return size == 0 ? NULL : vmalloc(size);
}
#endif /* !CONFIG_MMU */
void module_free(struct module *module, void *region)
{
vfree(region);
}
int module_frob_arch_sections(Elf_Ehdr *hdr,
Elf_Shdr *sechdrs,
char *secstrings,
struct module *mod)
{
#ifdef CONFIG_ARM_UNWIND
Elf_Shdr *s, *sechdrs_end = sechdrs + hdr->e_shnum;
for (s = sechdrs; s < sechdrs_end; s++) {
if (strcmp(".ARM.exidx.init.text", secstrings + s->sh_name) == 0)
mod->arch.unw_sec_init = s;
else if (strcmp(".ARM.exidx.devinit.text", secstrings + s->sh_name) == 0)
mod->arch.unw_sec_devinit = s;
else if (strcmp(".ARM.exidx", secstrings + s->sh_name) == 0)
mod->arch.unw_sec_core = s;
else if (strcmp(".init.text", secstrings + s->sh_name) == 0)
mod->arch.sec_init_text = s;
else if (strcmp(".devinit.text", secstrings + s->sh_name) == 0)
mod->arch.sec_devinit_text = s;
else if (strcmp(".text", secstrings + s->sh_name) == 0)
mod->arch.sec_core_text = s;
}
#endif
return 0;
}
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;
s32 offset;
u32 upper, lower, sign, j1, j2;
offset = ELF32_R_SYM(rel->r_info);
if (offset < 0 || offset > (symsec->sh_size / sizeof(Elf32_Sym))) {
printk(KERN_ERR "%s: bad relocation, section %d reloc %d\n",
module->name, relindex, i);
return -ENOEXEC;
}
sym = ((Elf32_Sym *)symsec->sh_addr) + offset;
if (rel->r_offset < 0 || rel->r_offset > dstsec->sh_size - sizeof(u32)) {
printk(KERN_ERR "%s: out of bounds relocation, "
"section %d reloc %d offset %d size %d\n",
module->name, relindex, i, 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:
*(u32 *)loc += sym->st_value;
break;
case R_ARM_PC24:
case R_ARM_CALL:
case R_ARM_JUMP24:
offset = (*(u32 *)loc & 0x00ffffff) << 2;
if (offset & 0x02000000)
offset -= 0x04000000;
offset += sym->st_value - loc;
if (offset & 3 ||
offset <= (s32)0xfe000000 ||
offset >= (s32)0x02000000) {
printk(KERN_ERR
"%s: relocation out of range, section "
"%d reloc %d sym '%s'\n", module->name,
relindex, i, strtab + sym->st_name);
return -ENOEXEC;
}
offset >>= 2;
*(u32 *)loc &= 0xff000000;
*(u32 *)loc |= offset & 0x00ffffff;
break;
case R_ARM_V4BX:
/* Preserve Rm and the condition code. Alter
* other bits to re-code instruction as
* MOV PC,Rm.
*/
*(u32 *)loc &= 0xf000000f;
*(u32 *)loc |= 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 = *(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;
*(u32 *)loc &= 0xfff0f000;
*(u32 *)loc |= ((offset & 0xf000) << 4) |
(offset & 0x0fff);
break;
case R_ARM_THM_CALL:
case R_ARM_THM_JUMP24:
upper = *(u16 *)loc;
lower = *(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;
/* only Thumb addresses allowed (no interworking) */
if (!(offset & 1) ||
offset <= (s32)0xff000000 ||
offset >= (s32)0x01000000) {
printk(KERN_ERR
"%s: relocation out of range, section "
"%d reloc %d sym '%s'\n", module->name,
relindex, i, strtab + sym->st_name);
return -ENOEXEC;
}
sign = (offset >> 24) & 1;
j1 = sign ^ (~(offset >> 23) & 1);
j2 = sign ^ (~(offset >> 22) & 1);
*(u16 *)loc = (u16)((upper & 0xf800) | (sign << 10) |
((offset >> 12) & 0x03ff));
*(u16 *)(loc + 2) = (u16)((lower & 0xd000) |
(j1 << 13) | (j2 << 11) |
((offset >> 1) & 0x07ff));
upper = *(u16 *)loc;
lower = *(u16 *)(loc + 2);
break;
default:
printk(KERN_ERR "%s: unknown relocation: %u\n",
module->name, ELF32_R_TYPE(rel->r_info));
return -ENOEXEC;
}
}
return 0;
}
int
apply_relocate_add(Elf32_Shdr *sechdrs, const char *strtab,
unsigned int symindex, unsigned int relsec, struct module *module)
{
printk(KERN_ERR "module %s: ADD RELOCATION unsupported\n",
module->name);
return -ENOEXEC;
}
#ifdef CONFIG_ARM_UNWIND
static void register_unwind_tables(struct module *mod)
{
if (mod->arch.unw_sec_init && mod->arch.sec_init_text)
mod->arch.unwind_init =
unwind_table_add(mod->arch.unw_sec_init->sh_addr,
mod->arch.unw_sec_init->sh_size,
mod->arch.sec_init_text->sh_addr,
mod->arch.sec_init_text->sh_size);
if (mod->arch.unw_sec_devinit && mod->arch.sec_devinit_text)
mod->arch.unwind_devinit =
unwind_table_add(mod->arch.unw_sec_devinit->sh_addr,
mod->arch.unw_sec_devinit->sh_size,
mod->arch.sec_devinit_text->sh_addr,
mod->arch.sec_devinit_text->sh_size);
if (mod->arch.unw_sec_core && mod->arch.sec_core_text)
mod->arch.unwind_core =
unwind_table_add(mod->arch.unw_sec_core->sh_addr,
mod->arch.unw_sec_core->sh_size,
mod->arch.sec_core_text->sh_addr,
mod->arch.sec_core_text->sh_size);
}
static void unregister_unwind_tables(struct module *mod)
{
unwind_table_del(mod->arch.unwind_init);
unwind_table_del(mod->arch.unwind_devinit);
unwind_table_del(mod->arch.unwind_core);
}
#else
static inline void register_unwind_tables(struct module *mod) { }
static inline void unregister_unwind_tables(struct module *mod) { }
#endif
int
module_finalize(const Elf32_Ehdr *hdr, const Elf_Shdr *sechdrs,
struct module *module)
{
register_unwind_tables(module);
return 0;
}
void
module_arch_cleanup(struct module *mod)
{
unregister_unwind_tables(mod);
}