Release 4.14 arch/powerpc/kernel/module_64.c
/* Kernel module help for PPC64.
Copyright (C) 2001, 2003 Rusty Russell IBM Corporation.
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
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/elf.h>
#include <linux/moduleloader.h>
#include <linux/err.h>
#include <linux/vmalloc.h>
#include <linux/ftrace.h>
#include <linux/bug.h>
#include <linux/uaccess.h>
#include <asm/module.h>
#include <asm/firmware.h>
#include <asm/code-patching.h>
#include <linux/sort.h>
#include <asm/setup.h>
#include <asm/sections.h>
/* FIXME: We don't do .init separately. To do this, we'd need to have
a separate r2 value in the init and core section, and stub between
them, too.
Using a magic allocator which places modules within 32MB solves
this, and makes other things simpler. Anton?
--RR. */
#ifdef PPC64_ELF_ABI_v2
/* An address is simply the address of the function. */
typedef unsigned long func_desc_t;
static func_desc_t func_desc(unsigned long addr)
{
return addr;
}
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| Rusty Russell | 13 | 100.00% | 1 | 100.00% |
| Total | 13 | 100.00% | 1 | 100.00% |
static unsigned long func_addr(unsigned long addr)
{
return addr;
}
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static unsigned long stub_func_addr(func_desc_t func)
{
return func;
}
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| Total | 13 | 100.00% | 1 | 100.00% |
/* PowerPC64 specific values for the Elf64_Sym st_other field. */
#define STO_PPC64_LOCAL_BIT 5
#define STO_PPC64_LOCAL_MASK (7 << STO_PPC64_LOCAL_BIT)
#define PPC64_LOCAL_ENTRY_OFFSET(other) \
(((1 << (((other) & STO_PPC64_LOCAL_MASK) >> STO_PPC64_LOCAL_BIT)) >> 2) << 2)
static unsigned int local_entry_offset(const Elf64_Sym *sym)
{
/* sym->st_other indicates offset to local entry point
* (otherwise it will assume r12 is the address of the start
* of function and try to derive r2 from it). */
return PPC64_LOCAL_ENTRY_OFFSET(sym->st_other);
}
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| Rusty Russell | 21 | 100.00% | 1 | 100.00% |
| Total | 21 | 100.00% | 1 | 100.00% |
#else
/* An address is address of the OPD entry, which contains address of fn. */
typedef struct ppc64_opd_entry func_desc_t;
static func_desc_t func_desc(unsigned long addr)
{
return *(struct ppc64_opd_entry *)addr;
}
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| Rusty Russell | 19 | 100.00% | 1 | 100.00% |
| Total | 19 | 100.00% | 1 | 100.00% |
static unsigned long func_addr(unsigned long addr)
{
return func_desc(addr).funcaddr;
}
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| Rusty Russell | 19 | 100.00% | 1 | 100.00% |
| Total | 19 | 100.00% | 1 | 100.00% |
static unsigned long stub_func_addr(func_desc_t func)
{
return func.funcaddr;
}
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| Rusty Russell | 15 | 100.00% | 1 | 100.00% |
| Total | 15 | 100.00% | 1 | 100.00% |
static unsigned int local_entry_offset(const Elf64_Sym *sym)
{
return 0;
}
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| Total | 15 | 100.00% | 1 | 100.00% |
#endif
#define STUB_MAGIC 0x73747562
/* stub */
/* Like PPC32, we need little trampolines to do > 24-bit jumps (into
the kernel itself). But on PPC64, these need to be used for every
jump, actually, to reset r2 (TOC+0x8000). */
struct ppc64_stub_entry
{
/* 28 byte jump instruction sequence (7 instructions). We only
* need 6 instructions on ABIv2 but we always allocate 7 so
* so we don't have to modify the trampoline load instruction. */
u32 jump[7];
/* Used by ftrace to identify stubs */
u32 magic;
/* Data for the above code */
func_desc_t funcdata;
};
/*
* PPC64 uses 24 bit jumps, but we need to jump into other modules or
* the kernel which may be further. So we jump to a stub.
*
* For ELFv1 we need to use this to set up the new r2 value (aka TOC
* pointer). For ELFv2 it's the callee's responsibility to set up the
* new r2, but for both we need to save the old r2.
*
* We could simply patch the new r2 value and function pointer into
* the stub, but it's significantly shorter to put these values at the
* end of the stub code, and patch the stub address (32-bits relative
* to the TOC ptr, r2) into the stub.
*/
static u32 ppc64_stub_insns[] = {
0x3d620000, /* addis r11,r2, <high> */
0x396b0000, /* addi r11,r11, <low> */
/* Save current r2 value in magic place on the stack. */
0xf8410000|R2_STACK_OFFSET, /* std r2,R2_STACK_OFFSET(r1) */
0xe98b0020, /* ld r12,32(r11) */
#ifdef PPC64_ELF_ABI_v1
/* Set up new r2 from function descriptor */
0xe84b0028, /* ld r2,40(r11) */
#endif
0x7d8903a6, /* mtctr r12 */
0x4e800420 /* bctr */
};
#ifdef CONFIG_DYNAMIC_FTRACE
int module_trampoline_target(struct module *mod, unsigned long addr,
unsigned long *target)
{
struct ppc64_stub_entry *stub;
func_desc_t funcdata;
u32 magic;
if (!within_module_core(addr, mod)) {
pr_err("%s: stub %lx not in module %s\n", __func__, addr, mod->name);
return -EFAULT;
}
stub = (struct ppc64_stub_entry *)addr;
if (probe_kernel_read(&magic, &stub->magic, sizeof(magic))) {
pr_err("%s: fault reading magic for stub %lx for %s\n", __func__, addr, mod->name);
return -EFAULT;
}
if (magic != STUB_MAGIC) {
pr_err("%s: bad magic for stub %lx for %s\n", __func__, addr, mod->name);
return -EFAULT;
}
if (probe_kernel_read(&funcdata, &stub->funcdata, sizeof(funcdata))) {
pr_err("%s: fault reading funcdata for stub %lx for %s\n", __func__, addr, mod->name);
return -EFAULT;
}
*target = stub_func_addr(funcdata);
return 0;
}
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| Michael Ellerman | 94 | 52.81% | 1 | 33.33% |
| Anton Blanchard | 84 | 47.19% | 2 | 66.67% |
| Total | 178 | 100.00% | 3 | 100.00% |
#endif
/* Count how many different 24-bit relocations (different symbol,
different addend) */
static unsigned int count_relocs(const Elf64_Rela *rela, unsigned int num)
{
unsigned int i, r_info, r_addend, _count_relocs;
/* FIXME: Only count external ones --RR */
_count_relocs = 0;
r_info = 0;
r_addend = 0;
for (i = 0; i < num; i++)
/* Only count 24-bit relocs, others don't need stubs */
if (ELF64_R_TYPE(rela[i].r_info) == R_PPC_REL24 &&
(r_info != ELF64_R_SYM(rela[i].r_info) ||
r_addend != rela[i].r_addend)) {
_count_relocs++;
r_info = ELF64_R_SYM(rela[i].r_info);
r_addend = rela[i].r_addend;
}
return _count_relocs;
}
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| Person | Tokens | Prop | Commits | CommitProp |
| Anton Blanchard | 75 | 63.03% | 1 | 50.00% |
| Emil Medve | 44 | 36.97% | 1 | 50.00% |
| Total | 119 | 100.00% | 2 | 100.00% |
static int relacmp(const void *_x, const void *_y)
{
const Elf64_Rela *x, *y;
y = (Elf64_Rela *)_x;
x = (Elf64_Rela *)_y;
/* Compare the entire r_info (as opposed to ELF64_R_SYM(r_info) only) to
* make the comparison cheaper/faster. It won't affect the sorting or
* the counting algorithms' performance
*/
if (x->r_info < y->r_info)
return -1;
else if (x->r_info > y->r_info)
return 1;
else if (x->r_addend < y->r_addend)
return -1;
else if (x->r_addend > y->r_addend)
return 1;
else
return 0;
}
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| Person | Tokens | Prop | Commits | CommitProp |
| Emil Medve | 102 | 100.00% | 1 | 100.00% |
| Total | 102 | 100.00% | 1 | 100.00% |
static void relaswap(void *_x, void *_y, int size)
{
uint64_t *x, *y, tmp;
int i;
y = (uint64_t *)_x;
x = (uint64_t *)_y;
for (i = 0; i < sizeof(Elf64_Rela) / sizeof(uint64_t); i++) {
tmp = x[i];
x[i] = y[i];
y[i] = tmp;
}
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Emil Medve | 92 | 100.00% | 1 | 100.00% |
| Total | 92 | 100.00% | 1 | 100.00% |
/* Get size of potential trampolines required. */
static unsigned long get_stubs_size(const Elf64_Ehdr *hdr,
const Elf64_Shdr *sechdrs)
{
/* One extra reloc so it's always 0-funcaddr terminated */
unsigned long relocs = 1;
unsigned i;
/* Every relocated section... */
for (i = 1; i < hdr->e_shnum; i++) {
if (sechdrs[i].sh_type == SHT_RELA) {
pr_debug("Found relocations in section %u\n", i);
pr_debug("Ptr: %p. Number: %Lu\n",
(void *)sechdrs[i].sh_addr,
sechdrs[i].sh_size / sizeof(Elf64_Rela));
/* Sort the relocation information based on a symbol and
* addend key. This is a stable O(n*log n) complexity
* alogrithm but it will reduce the complexity of
* count_relocs() to linear complexity O(n)
*/
sort((void *)sechdrs[i].sh_addr,
sechdrs[i].sh_size / sizeof(Elf64_Rela),
sizeof(Elf64_Rela), relacmp, relaswap);
relocs += count_relocs((void *)sechdrs[i].sh_addr,
sechdrs[i].sh_size
/ sizeof(Elf64_Rela));
}
}
#ifdef CONFIG_DYNAMIC_FTRACE
/* make the trampoline to the ftrace_caller */
relocs++;
#endif
pr_debug("Looks like a total of %lu stubs, max\n", relocs);
return relocs * sizeof(struct ppc64_stub_entry);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Anton Blanchard | 137 | 75.27% | 2 | 50.00% |
| Emil Medve | 36 | 19.78% | 1 | 25.00% |
| Steven Rostedt | 9 | 4.95% | 1 | 25.00% |
| Total | 182 | 100.00% | 4 | 100.00% |
/* Still needed for ELFv2, for .TOC. */
static void dedotify_versions(struct modversion_info *vers,
unsigned long size)
{
struct modversion_info *end;
for (end = (void *)vers + size; vers < end; vers++)
if (vers->name[0] == '.') {
memmove(vers->name, vers->name+1, strlen(vers->name));
}
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Andrew Morton | 70 | 97.22% | 1 | 50.00% |
| Laurent Dufour | 2 | 2.78% | 1 | 50.00% |
| Total | 72 | 100.00% | 2 | 100.00% |
/*
* Undefined symbols which refer to .funcname, hack to funcname. Make .TOC.
* seem to be defined (value set later).
*/
static void dedotify(Elf64_Sym *syms, unsigned int numsyms, char *strtab)
{
unsigned int i;
for (i = 1; i < numsyms; i++) {
if (syms[i].st_shndx == SHN_UNDEF) {
char *name = strtab + syms[i].st_name;
if (name[0] == '.') {
if (strcmp(name+1, "TOC.") == 0)
syms[i].st_shndx = SHN_ABS;
syms[i].st_name++;
}
}
}
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Anton Blanchard | 73 | 70.19% | 1 | 33.33% |
| Alan Modra | 24 | 23.08% | 1 | 33.33% |
| Andreas Schwab | 7 | 6.73% | 1 | 33.33% |
| Total | 104 | 100.00% | 3 | 100.00% |
static Elf64_Sym *find_dot_toc(Elf64_Shdr *sechdrs,
const char *strtab,
unsigned int symindex)
{
unsigned int i, numsyms;
Elf64_Sym *syms;
syms = (Elf64_Sym *)sechdrs[symindex].sh_addr;
numsyms = sechdrs[symindex].sh_size / sizeof(Elf64_Sym);
for (i = 1; i < numsyms; i++) {
if (syms[i].st_shndx == SHN_ABS
&& strcmp(strtab + syms[i].st_name, "TOC.") == 0)
return &syms[i];
}
return NULL;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Rusty Russell | 108 | 99.08% | 2 | 66.67% |
| Alan Modra | 1 | 0.92% | 1 | 33.33% |
| Total | 109 | 100.00% | 3 | 100.00% |
int module_frob_arch_sections(Elf64_Ehdr *hdr,
Elf64_Shdr *sechdrs,
char *secstrings,
struct module *me)
{
unsigned int i;
/* Find .toc and .stubs sections, symtab and strtab */
for (i = 1; i < hdr->e_shnum; i++) {
char *p;
if (strcmp(secstrings + sechdrs[i].sh_name, ".stubs") == 0)
me->arch.stubs_section = i;
else if (strcmp(secstrings + sechdrs[i].sh_name, ".toc") == 0)
me->arch.toc_section = i;
else if (strcmp(secstrings+sechdrs[i].sh_name,"__versions")==0)
dedotify_versions((void *)hdr + sechdrs[i].sh_offset,
sechdrs[i].sh_size);
/* We don't handle .init for the moment: rename to _init */
while ((p = strstr(secstrings + sechdrs[i].sh_name, ".init")))
p[0] = '_';
if (sechdrs[i].sh_type == SHT_SYMTAB)
dedotify((void *)hdr + sechdrs[i].sh_offset,
sechdrs[i].sh_size / sizeof(Elf64_Sym),
(void *)hdr
+ sechdrs[sechdrs[i].sh_link].sh_offset);
}
if (!me->arch.stubs_section) {
pr_err("%s: doesn't contain .stubs.\n", me->name);
return -ENOEXEC;
}
/* If we don't have a .toc, just use .stubs. We need to set r2
to some reasonable value in case the module calls out to
other functions via a stub, or if a function pointer escapes
the module by some means. */
if (!me->arch.toc_section)
me->arch.toc_section = me->arch.stubs_section;
/* Override the stubs size */
sechdrs[me->arch.stubs_section].sh_size = get_stubs_size(hdr, sechdrs);
return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Anton Blanchard | 231 | 78.04% | 3 | 60.00% |
| Andrew Morton | 42 | 14.19% | 1 | 20.00% |
| Alan Modra | 23 | 7.77% | 1 | 20.00% |
| Total | 296 | 100.00% | 5 | 100.00% |
/* r2 is the TOC pointer: it actually points 0x8000 into the TOC (this
gives the value maximum span in an instruction which uses a signed
offset) */
static inline unsigned long my_r2(const Elf64_Shdr *sechdrs, struct module *me)
{
return sechdrs[me->arch.toc_section].sh_addr + 0x8000;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Anton Blanchard | 31 | 96.88% | 1 | 50.00% |
| Michael Ellerman | 1 | 3.12% | 1 | 50.00% |
| Total | 32 | 100.00% | 2 | 100.00% |
/* Both low and high 16 bits are added as SIGNED additions, so if low
16 bits has high bit set, high 16 bits must be adjusted. These
macros do that (stolen from binutils). */
#define PPC_LO(v) ((v) & 0xffff)
#define PPC_HI(v) (((v) >> 16) & 0xffff)
#define PPC_HA(v) PPC_HI ((v) + 0x8000)
/* Patch stub to reference function and correct r2 value. */
static inline int create_stub(const Elf64_Shdr *sechdrs,
struct ppc64_stub_entry *entry,
unsigned long addr,
struct module *me)
{
long reladdr;
memcpy(entry->jump, ppc64_stub_insns, sizeof(ppc64_stub_insns));
/* Stub uses address relative to r2. */
reladdr = (unsigned long)entry - my_r2(sechdrs, me);
if (reladdr > 0x7FFFFFFF || reladdr < -(0x80000000L)) {
pr_err("%s: Address %p of stub out of range of %p.\n",
me->name, (void *)reladdr, (void *)my_r2);
return 0;
}
pr_debug("Stub %p get data from reladdr %li\n", entry, reladdr);
entry->jump[0] |= PPC_HA(reladdr);
entry->jump[1] |= PPC_LO(reladdr);
entry->funcdata = func_desc(addr);
entry->magic = STUB_MAGIC;
return 1;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Anton Blanchard | 120 | 80.54% | 4 | 50.00% |
| Rusty Russell | 22 | 14.77% | 2 | 25.00% |
| Michael Ellerman | 7 | 4.70% | 2 | 25.00% |
| Total | 149 | 100.00% | 8 | 100.00% |
/* Create stub to jump to function described in this OPD/ptr: we need the
stub to set up the TOC ptr (r2) for the function. */
static unsigned long stub_for_addr(const Elf64_Shdr *sechdrs,
unsigned long addr,
struct module *me)
{
struct ppc64_stub_entry *stubs;
unsigned int i, num_stubs;
num_stubs = sechdrs[me->arch.stubs_section].sh_size / sizeof(*stubs);
/* Find this stub, or if that fails, the next avail. entry */
stubs = (void *)sechdrs[me->arch.stubs_section].sh_addr;
for (i = 0; stub_func_addr(stubs[i].funcdata); i++) {
BUG_ON(i >= num_stubs);
if (stub_func_addr(stubs[i].funcdata) == func_addr(addr))
return (unsigned long)&stubs[i];
}
if (!create_stub(sechdrs, &stubs[i], addr, me))
return 0;
return (unsigned long)&stubs[i];
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Anton Blanchard | 142 | 90.45% | 2 | 50.00% |
| Rusty Russell | 14 | 8.92% | 1 | 25.00% |
| Michael Ellerman | 1 | 0.64% | 1 | 25.00% |
| Total | 157 | 100.00% | 4 | 100.00% |
#ifdef CC_USING_MPROFILE_KERNEL
static bool is_early_mcount_callsite(u32 *instruction)
{
/*
* Check if this is one of the -mprofile-kernel sequences.
*/
if (instruction[-1] == PPC_INST_STD_LR &&
instruction[-2] == PPC_INST_MFLR)
return true;
if (instruction[-1] == PPC_INST_MFLR)
return true;
return false;
}
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| Person | Tokens | Prop | Commits | CommitProp |
| Torsten Duwe | 48 | 100.00% | 1 | 100.00% |
| Total | 48 | 100.00% | 1 | 100.00% |
/*
* In case of _mcount calls, do not save the current callee's TOC (in r2) into
* the original caller's stack frame. If we did we would clobber the saved TOC
* value of the original caller.
*/
static void squash_toc_save_inst(const char *name, unsigned long addr)
{
struct ppc64_stub_entry *stub = (struct ppc64_stub_entry *)addr;
/* Only for calls to _mcount */
if (strcmp("_mcount", name) != 0)
return;
stub->jump[2] = PPC_INST_NOP;
}
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| Torsten Duwe | 49 | 100.00% | 1 | 100.00% |
| Total | 49 | 100.00% | 1 | 100.00% |
#else
static void squash_toc_save_inst(const char *name, unsigned long addr) { }
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| Torsten Duwe | 14 | 100.00% | 1 | 100.00% |
| Total | 14 | 100.00% | 1 | 100.00% |
/* without -mprofile-kernel, mcount calls are never early */
static bool is_early_mcount_callsite(u32 *instruction)
{
return false;
}
Contributors
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| Torsten Duwe | 13 | 100.00% | 1 | 100.00% |
| Total | 13 | 100.00% | 1 | 100.00% |
#endif
/* We expect a noop next: if it is, replace it with instruction to
restore r2. */
static int restore_r2(u32 *instruction, struct module *me)
{
if (is_early_mcount_callsite(instruction - 1))
return 1;
if (*instruction != PPC_INST_NOP) {
pr_err("%s: Expect noop after relocate, got %08x\n",
me->name, *instruction);
return 0;
}
/* ld r2,R2_STACK_OFFSET(r1) */
*instruction = PPC_INST_LD_TOC;
return 1;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Anton Blanchard | 40 | 66.67% | 3 | 50.00% |
| Torsten Duwe | 11 | 18.33% | 1 | 16.67% |
| Michael Ellerman | 8 | 13.33% | 1 | 16.67% |
| Rusty Russell | 1 | 1.67% | 1 | 16.67% |
| Total | 60 | 100.00% | 6 | 100.00% |
int apply_relocate_add(Elf64_Shdr *sechdrs,
const char *strtab,
unsigned int symindex,
unsigned int relsec,
struct module *me)
{
unsigned int i;
Elf64_Rela *rela = (void *)sechdrs[relsec].sh_addr;
Elf64_Sym *sym;
unsigned long *location;
unsigned long value;
pr_debug("Applying ADD relocate section %u to %u\n", relsec,
sechdrs[relsec].sh_info);
/* First time we're called, we can fix up .TOC. */
if (!me->arch.toc_fixed) {
sym = find_dot_toc(sechdrs, strtab, symindex);
/* It's theoretically possible that a module doesn't want a
* .TOC. so don't fail it just for that. */
if (sym)
sym->st_value = my_r2(sechdrs, me);
me->arch.toc_fixed = true;
}
for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rela); i++) {
/* This is where to make the change */
location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
+ rela[i].r_offset;
/* This is the symbol it is referring to */
sym = (Elf64_Sym *)sechdrs[symindex].sh_addr
+ ELF64_R_SYM(rela[i].r_info);
pr_debug("RELOC at %p: %li-type as %s (0x%lx) + %li\n",
location, (long)ELF64_R_TYPE(rela[i].r_info),
strtab + sym->st_name, (unsigned long)sym->st_value,
(long)rela[i].r_addend);
/* `Everything is relative'. */
value = sym->st_value + rela[i].r_addend;
switch (ELF64_R_TYPE(rela[i].r_info)) {
case R_PPC64_ADDR32:
/* Simply set it */
*(u32 *)location = value;
break;
case R_PPC64_ADDR64:
/* Simply set it */
*(unsigned long *)location = value;
break;
case R_PPC64_TOC:
*(unsigned long *)location = my_r2(sechdrs, me);
break;
case R_PPC64_TOC16:
/* Subtract TOC pointer */
value -= my_r2(sechdrs, me);
if (value + 0x8000 > 0xffff) {
pr_err("%s: bad TOC16 relocation (0x%lx)\n",
me->name, value);
return -ENOEXEC;
}
*((uint16_t *) location)
= (*((uint16_t *) location) & ~0xffff)
| (value & 0xffff);
break;
case R_PPC64_TOC16_LO:
/* Subtract TOC pointer */
value -= my_r2(sechdrs, me);
*((uint16_t *) location)
= (*((uint16_t *) location) & ~0xffff)
| (value & 0xffff);
break;
case R_PPC64_TOC16_DS:
/* Subtract TOC pointer */
value -= my_r2(sechdrs, me);
if ((value & 3) != 0 || value + 0x8000 > 0xffff) {
pr_err("%s: bad TOC16_DS relocation (0x%lx)\n",
me->name, value);
return -ENOEXEC;
}
*((uint16_t *) location)
= (*((uint16_t *) location) & ~0xfffc)
| (value & 0xfffc);
break;
case R_PPC64_TOC16_LO_DS:
/* Subtract TOC pointer */
value -= my_r2(sechdrs, me);
if ((value & 3) != 0) {
pr_err("%s: bad TOC16_LO_DS relocation (0x%lx)\n",
me->name, value);
return -ENOEXEC;
}
*((uint16_t *) location)
= (*((uint16_t *) location) & ~0xfffc)
| (value & 0xfffc);
break;
case R_PPC64_TOC16_HA:
/* Subtract TOC pointer */
value -= my_r2(sechdrs, me);
value = ((value + 0x8000) >> 16);
*((uint16_t *) location)
= (*((uint16_t *) location) & ~0xffff)
| (value & 0xffff);
break;
case R_PPC_REL24:
/* FIXME: Handle weak symbols here --RR */
if (sym->st_shndx == SHN_UNDEF) {
/* External: go via stub */
value = stub_for_addr(sechdrs, value, me);
if (!value)
return -ENOENT;
if (!restore_r2((u32 *)location + 1, me))
return -ENOEXEC;
squash_toc_save_inst(strtab + sym->st_name, value);
} else
value += local_entry_offset(sym);
/* Convert value to relative */
value -= (unsigned long)location;
if (value + 0x2000000 > 0x3ffffff || (value & 3) != 0){
pr_err("%s: REL24 %li out of range!\n",
me->name, (long int)value);
return -ENOEXEC;
}
/* Only replace bits 2 through 26 */
*(uint32_t *)location
= (*(uint32_t *)location & ~0x03fffffc)
| (value & 0x03fffffc);
break;
case R_PPC64_REL64:
/* 64 bits relative (used by features fixups) */
*location = value - (unsigned long)location;
break;
case R_PPC64_REL32:
/* 32 bits relative (used by relative exception tables) */
*(u32 *)location = value - (unsigned long)location;
break;
case R_PPC64_TOCSAVE:
/*
* Marker reloc indicates we don't have to save r2.
* That would only save us one instruction, so ignore
* it.
*/
break;
case R_PPC64_ENTRY:
/*
* Optimize ELFv2 large code model entry point if
* the TOC is within 2GB range of current location.
*/
value = my_r2(sechdrs, me) - (unsigned long)location;
if (value + 0x80008000 > 0xffffffff)
break;
/*
* Check for the large code model prolog sequence:
* ld r2, ...(r12)
* add r2, r2, r12
*/
if ((((uint32_t *)location)[0] & ~0xfffc)
!= 0xe84c0000)
break;
if (((uint32_t *)location)[1] != 0x7c426214)
break;
/*
* If found, replace it with:
* addis r2, r12, (.TOC.-func)@ha
* addi r2, r12, (.TOC.-func)@l
*/
((uint32_t *)location)[0] = 0x3c4c0000 + PPC_HA(value);
((uint32_t *)location)[1] = 0x38420000 + PPC_LO(value);
break;
case R_PPC64_REL16_HA:
/* Subtract location pointer */
value -= (unsigned long)location;
value = ((value + 0x8000) >> 16);
*((uint16_t *) location)
= (*((uint16_t *) location) & ~0xffff)
| (value & 0xffff);
break;
case R_PPC64_REL16_LO:
/* Subtract location pointer */
value -= (unsigned long)location;
*((uint16_t *) location)
= (*((uint16_t *) location) & ~0xffff)
| (value & 0xffff);
break;
default:
pr_err("%s: Unknown ADD relocation: %lu\n",
me->name,
(unsigned long)ELF64_R_TYPE(rela[i].r_info));
return -ENOEXEC;
}
}
return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Anton Blanchard | 669 | 63.90% | 4 | 26.67% |
| Rusty Russell | 156 | 14.90% | 4 | 26.67% |
| Ulrich Weigand | 104 | 9.93% | 1 | 6.67% |
| Peter Bergner | 65 | 6.21% | 1 | 6.67% |
| Michael Ellerman | 24 | 2.29% | 2 | 13.33% |
| Benjamin Herrenschmidt | 16 | 1.53% | 1 | 6.67% |
| Torsten Duwe | 11 | 1.05% | 1 | 6.67% |
| Alan Modra | 2 | 0.19% | 1 | 6.67% |
| Total | 1047 | 100.00% | 15 | 100.00% |
#ifdef CONFIG_DYNAMIC_FTRACE
#ifdef CC_USING_MPROFILE_KERNEL
#define PACATOC offsetof(struct paca_struct, kernel_toc)
/*
* For mprofile-kernel we use a special stub for ftrace_caller() because we
* can't rely on r2 containing this module's TOC when we enter the stub.
*
* That can happen if the function calling us didn't need to use the toc. In
* that case it won't have setup r2, and the r2 value will be either the
* kernel's toc, or possibly another modules toc.
*
* To deal with that this stub uses the kernel toc, which is always accessible
* via the paca (in r13). The target (ftrace_caller()) is responsible for
* saving and restoring the toc before returning.
*/
static unsigned long create_ftrace_stub(const Elf64_Shdr *sechdrs, struct module *me)
{
struct ppc64_stub_entry *entry;
unsigned int i, num_stubs;
static u32 stub_insns[] = {
0xe98d0000 | PACATOC, /* ld r12,PACATOC(r13) */
0x3d8c0000, /* addis r12,r12,<high> */
0x398c0000, /* addi r12,r12,<low> */
0x7d8903a6, /* mtctr r12 */
0x4e800420, /* bctr */
};
long reladdr;
num_stubs = sechdrs[me->arch.stubs_section].sh_size / sizeof(*entry);
/* Find the next available stub entry */
entry = (void *)sechdrs[me->arch.stubs_section].sh_addr;
for (i = 0; i < num_stubs && stub_func_addr(entry->funcdata); i++, entry++);
if (i >= num_stubs) {
pr_err("%s: Unable to find a free slot for ftrace stub.\n", me->name);
return 0;
}
memcpy(entry->jump, stub_insns, sizeof(stub_insns));
/* Stub uses address relative to kernel toc (from the paca) */
reladdr = (unsigned long)ftrace_caller - kernel_toc_addr();
if (reladdr > 0x7FFFFFFF || reladdr < -(0x80000000L)) {
pr_err("%s: Address of ftrace_caller out of range of kernel_toc.\n", me->name);
return 0;
}
entry->jump[1] |= PPC_HA(reladdr);
entry->jump[2] |= PPC_LO(reladdr);
/* Eventhough we don't use funcdata in the stub, it's needed elsewhere. */
entry->funcdata = func_desc((unsigned long)ftrace_caller);
entry->magic = STUB_MAGIC;
return (unsigned long)entry;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Michael Ellerman | 233 | 96.68% | 1 | 50.00% |
| Steven Rostedt | 8 | 3.32% | 1 | 50.00% |
| Total | 241 | 100.00% | 2 | 100.00% |
#else
static unsigned long create_ftrace_stub(const Elf64_Shdr *sechdrs, struct module *me)
{
return stub_for_addr(sechdrs, (unsigned long)ftrace_caller, me);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Michael Ellerman | 19 | 61.29% | 1 | 50.00% |
| Steven Rostedt | 12 | 38.71% | 1 | 50.00% |
| Total | 31 | 100.00% | 2 | 100.00% |
#endif
int module_finalize_ftrace(struct module *mod, const Elf_Shdr *sechdrs)
{
mod->arch.toc = my_r2(sechdrs, mod);
mod->arch.tramp = create_ftrace_stub(sechdrs, mod);
if (!mod->arch.tramp)
return -ENOENT;
return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Michael Ellerman | 32 | 56.14% | 2 | 50.00% |
| Steven Rostedt | 21 | 36.84% | 1 | 25.00% |
| Anton Blanchard | 4 | 7.02% | 1 | 25.00% |
| Total | 57 | 100.00% | 4 | 100.00% |
#endif
Overall Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Anton Blanchard | 1700 | 48.67% | 8 | 21.05% |
| Rusty Russell | 489 | 14.00% | 10 | 26.32% |
| Michael Ellerman | 450 | 12.88% | 7 | 18.42% |
| Emil Medve | 277 | 7.93% | 1 | 2.63% |
| Torsten Duwe | 155 | 4.44% | 1 | 2.63% |
| Andrew Morton | 112 | 3.21% | 1 | 2.63% |
| Ulrich Weigand | 104 | 2.98% | 1 | 2.63% |
| Peter Bergner | 65 | 1.86% | 1 | 2.63% |
| Steven Rostedt | 58 | 1.66% | 1 | 2.63% |
| Alan Modra | 51 | 1.46% | 2 | 5.26% |
| Benjamin Herrenschmidt | 19 | 0.54% | 1 | 2.63% |
| Andreas Schwab | 7 | 0.20% | 1 | 2.63% |
| Jeremy Fitzhardinge | 3 | 0.09% | 1 | 2.63% |
| Laurent Dufour | 2 | 0.06% | 1 | 2.63% |
| Robert Jennings | 1 | 0.03% | 1 | 2.63% |
| Total | 3493 | 100.00% | 38 | 100.00% |
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