Commit dfe2cbd1 authored by Rusty Russell's avatar Rusty Russell Committed by Linus Torvalds

[PATCH] Modules 1/3: remove common section handling

As RTH pointed out, we use -fno-common for the kernel (otherwise we'd
have to sort out the small symbols anyway).

So the common section allocation in the module code is pointless.
parent d434727a
......@@ -840,37 +840,10 @@ static int handle_section(const char *name,
return ret;
}
/* Figure out total size desired for the common vars */
static unsigned long read_commons(void *start, Elf_Shdr *sechdr)
{
unsigned long size, i, max_align;
Elf_Sym *sym;
size = max_align = 0;
for (sym = start + sechdr->sh_offset, i = 0;
i < sechdr->sh_size / sizeof(Elf_Sym);
i++) {
if (sym[i].st_shndx == SHN_COMMON) {
/* Value encodes alignment. */
if (sym[i].st_value > max_align)
max_align = sym[i].st_value;
/* Pad to required alignment */
size = ALIGN(size, sym[i].st_value) + sym[i].st_size;
}
}
/* Now, add in max alignment requirement (with align
attribute, this could be large), so we know we have space
whatever the start alignment is */
return size + max_align;
}
/* Change all symbols so that sh_value encodes the pointer directly. */
static void simplify_symbols(Elf_Shdr *sechdrs,
static int simplify_symbols(Elf_Shdr *sechdrs,
unsigned int symindex,
unsigned int strindex,
void *common,
struct module *mod)
{
unsigned int i;
......@@ -884,13 +857,10 @@ static void simplify_symbols(Elf_Shdr *sechdrs,
i++) {
switch (sym[i].st_shndx) {
case SHN_COMMON:
/* Value encodes alignment. */
common = (void *)ALIGN((unsigned long)common,
sym[i].st_value);
/* Change it to encode pointer */
sym[i].st_value = (unsigned long)common;
common += sym[i].st_size;
break;
/* We compiled with -fno-common. These are not
supposed to happen. */
DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
return -ENOEXEC;
case SHN_ABS:
/* Don't need to do anything */
......@@ -928,15 +898,16 @@ static void simplify_symbols(Elf_Shdr *sechdrs,
&ksg);
}
}
return 0;
}
/* Get the total allocation size of the init and non-init sections */
static struct sizes get_sizes(const Elf_Ehdr *hdr,
const Elf_Shdr *sechdrs,
const char *secstrings,
unsigned long common_length)
const char *secstrings)
{
struct sizes ret = { 0, common_length };
struct sizes ret = { 0, 0 };
unsigned i;
/* Everything marked ALLOC (this includes the exported
......@@ -971,7 +942,6 @@ static struct module *load_module(void *umod,
unsigned int i, symindex, exportindex, strindex, setupindex, exindex,
modindex, obsparmindex;
long arglen;
unsigned long common_length;
struct sizes sizes, used;
struct module *mod;
long err = 0;
......@@ -1089,9 +1059,8 @@ static struct module *load_module(void *umod,
mod->state = MODULE_STATE_COMING;
/* How much space will we need? (Common area in first) */
common_length = read_commons(hdr, &sechdrs[symindex]);
sizes = get_sizes(hdr, sechdrs, secstrings, common_length);
/* How much space will we need? */
sizes = get_sizes(hdr, sechdrs, secstrings);
/* Set these up, and allow archs to manipulate them. */
mod->core_size = sizes.core_size;
......@@ -1127,7 +1096,7 @@ static struct module *load_module(void *umod,
/* Transfer each section which requires ALLOC, and set sh_offset
fields to absolute addresses. */
used.core_size = common_length;
used.core_size = 0;
used.init_size = 0;
for (i = 1; i < hdr->e_shnum; i++) {
if (sechdrs[i].sh_flags & SHF_ALLOC) {
......@@ -1151,7 +1120,9 @@ static struct module *load_module(void *umod,
module_unload_init(mod);
/* Fix up syms, so that st_value is a pointer to location. */
simplify_symbols(sechdrs, symindex, strindex, mod->module_core, mod);
err = simplify_symbols(sechdrs, symindex, strindex, mod);
if (err < 0)
goto cleanup;
/* Set up EXPORTed symbols */
if (exportindex) {
......
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