mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-25 04:01:10 +00:00
elf: Make dl-fptr and dl-symaddr hppa specific
With ia64 removal, the function descriptor supports is only used by HPPA and new architectures do not seem leaning towards this design. Reviewed-by: Florian Weimer <fweimer@redhat.com>
This commit is contained in:
Adhemerval Zanella
parent
294a892769
commit
745c3cc10f
322
elf/dl-fptr.c
322
elf/dl-fptr.c
@ -1,322 +0,0 @@
|
||||
/* Manage function descriptors. Generic version.
|
||||
Copyright (C) 1999-2024 Free Software Foundation, Inc.
|
||||
This file is part of the GNU C Library.
|
||||
|
||||
The GNU C Library is free software; you can redistribute it and/or
|
||||
modify it under the terms of the GNU Lesser General Public
|
||||
License as published by the Free Software Foundation; either
|
||||
version 2.1 of the License, or (at your option) any later version.
|
||||
|
||||
The GNU C Library 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
|
||||
Lesser General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU Lesser General Public
|
||||
License along with the GNU C Library; if not, see
|
||||
<https://www.gnu.org/licenses/>. */
|
||||
|
||||
#include <libintl.h>
|
||||
#include <unistd.h>
|
||||
#include <string.h>
|
||||
#include <sys/param.h>
|
||||
#include <sys/mman.h>
|
||||
#include <link.h>
|
||||
#include <ldsodefs.h>
|
||||
#include <elf/dynamic-link.h>
|
||||
#include <dl-fptr.h>
|
||||
#include <dl-unmap-segments.h>
|
||||
#include <atomic.h>
|
||||
|
||||
#ifndef ELF_MACHINE_BOOT_FPTR_TABLE_LEN
|
||||
/* ELF_MACHINE_BOOT_FPTR_TABLE_LEN should be greater than the number of
|
||||
dynamic symbols in ld.so. */
|
||||
# define ELF_MACHINE_BOOT_FPTR_TABLE_LEN 256
|
||||
#endif
|
||||
|
||||
#ifndef ELF_MACHINE_LOAD_ADDRESS
|
||||
# error "ELF_MACHINE_LOAD_ADDRESS is not defined."
|
||||
#endif
|
||||
|
||||
#ifndef COMPARE_AND_SWAP
|
||||
# define COMPARE_AND_SWAP(ptr, old, new) \
|
||||
(catomic_compare_and_exchange_bool_acq (ptr, new, old) == 0)
|
||||
#endif
|
||||
|
||||
ElfW(Addr) _dl_boot_fptr_table [ELF_MACHINE_BOOT_FPTR_TABLE_LEN];
|
||||
|
||||
static struct local
|
||||
{
|
||||
struct fdesc_table *root;
|
||||
struct fdesc *free_list;
|
||||
unsigned int npages; /* # of pages to allocate */
|
||||
/* the next to members MUST be consecutive! */
|
||||
struct fdesc_table boot_table;
|
||||
struct fdesc boot_fdescs[1024];
|
||||
}
|
||||
local =
|
||||
{
|
||||
.root = &local.boot_table,
|
||||
.npages = 2,
|
||||
.boot_table =
|
||||
{
|
||||
.len = sizeof (local.boot_fdescs) / sizeof (local.boot_fdescs[0]),
|
||||
.first_unused = 0
|
||||
}
|
||||
};
|
||||
|
||||
/* Create a new fdesc table and return a pointer to the first fdesc
|
||||
entry. The fdesc lock must have been acquired already. */
|
||||
|
||||
static struct fdesc_table *
|
||||
new_fdesc_table (struct local *l, size_t *size)
|
||||
{
|
||||
size_t old_npages = l->npages;
|
||||
size_t new_npages = old_npages + old_npages;
|
||||
struct fdesc_table *new_table;
|
||||
|
||||
/* If someone has just created a new table, we return NULL to tell
|
||||
the caller to use the new table. */
|
||||
if (! COMPARE_AND_SWAP (&l->npages, old_npages, new_npages))
|
||||
return (struct fdesc_table *) NULL;
|
||||
|
||||
*size = old_npages * GLRO(dl_pagesize);
|
||||
new_table = __mmap (NULL, *size,
|
||||
PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0);
|
||||
if (new_table == MAP_FAILED)
|
||||
_dl_signal_error (errno, NULL, NULL,
|
||||
N_("cannot map pages for fdesc table"));
|
||||
|
||||
new_table->len
|
||||
= (*size - sizeof (*new_table)) / sizeof (struct fdesc);
|
||||
new_table->first_unused = 1;
|
||||
return new_table;
|
||||
}
|
||||
|
||||
|
||||
static ElfW(Addr)
|
||||
make_fdesc (ElfW(Addr) ip, ElfW(Addr) gp)
|
||||
{
|
||||
struct fdesc *fdesc = NULL;
|
||||
struct fdesc_table *root;
|
||||
unsigned int old;
|
||||
struct local *l;
|
||||
|
||||
ELF_MACHINE_LOAD_ADDRESS (l, local);
|
||||
|
||||
retry:
|
||||
root = l->root;
|
||||
while (1)
|
||||
{
|
||||
old = root->first_unused;
|
||||
if (old >= root->len)
|
||||
break;
|
||||
else if (COMPARE_AND_SWAP (&root->first_unused, old, old + 1))
|
||||
{
|
||||
fdesc = &root->fdesc[old];
|
||||
goto install;
|
||||
}
|
||||
}
|
||||
|
||||
if (l->free_list)
|
||||
{
|
||||
/* Get it from free-list. */
|
||||
do
|
||||
{
|
||||
fdesc = l->free_list;
|
||||
if (fdesc == NULL)
|
||||
goto retry;
|
||||
}
|
||||
while (! COMPARE_AND_SWAP ((ElfW(Addr) *) &l->free_list,
|
||||
(ElfW(Addr)) fdesc, fdesc->ip));
|
||||
}
|
||||
else
|
||||
{
|
||||
/* Create a new fdesc table. */
|
||||
size_t size;
|
||||
struct fdesc_table *new_table = new_fdesc_table (l, &size);
|
||||
|
||||
if (new_table == NULL)
|
||||
goto retry;
|
||||
|
||||
new_table->next = root;
|
||||
if (! COMPARE_AND_SWAP ((ElfW(Addr) *) &l->root,
|
||||
(ElfW(Addr)) root,
|
||||
(ElfW(Addr)) new_table))
|
||||
{
|
||||
/* Someone has just installed a new table. Return NULL to
|
||||
tell the caller to use the new table. */
|
||||
__munmap (new_table, size);
|
||||
goto retry;
|
||||
}
|
||||
|
||||
/* Note that the first entry was reserved while allocating the
|
||||
memory for the new page. */
|
||||
fdesc = &new_table->fdesc[0];
|
||||
}
|
||||
|
||||
install:
|
||||
fdesc->ip = ip;
|
||||
fdesc->gp = gp;
|
||||
|
||||
return (ElfW(Addr)) fdesc;
|
||||
}
|
||||
|
||||
|
||||
static inline ElfW(Addr) * __attribute__ ((always_inline))
|
||||
make_fptr_table (struct link_map *map)
|
||||
{
|
||||
const ElfW(Sym) *symtab
|
||||
= (const void *) D_PTR (map, l_info[DT_SYMTAB]);
|
||||
const char *strtab = (const void *) D_PTR (map, l_info[DT_STRTAB]);
|
||||
ElfW(Addr) *fptr_table;
|
||||
size_t size;
|
||||
size_t len;
|
||||
|
||||
/* XXX Apparently the only way to find out the size of the dynamic
|
||||
symbol section is to assume that the string table follows right
|
||||
afterwards... */
|
||||
len = ((strtab - (char *) symtab)
|
||||
/ map->l_info[DT_SYMENT]->d_un.d_val);
|
||||
size = ((len * sizeof (fptr_table[0]) + GLRO(dl_pagesize) - 1)
|
||||
& -GLRO(dl_pagesize));
|
||||
/* XXX We don't support here in the moment systems without MAP_ANON.
|
||||
There probably are none for IA-64. In case this is proven wrong
|
||||
we will have to open /dev/null here and use the file descriptor
|
||||
instead of the hard-coded -1. */
|
||||
fptr_table = __mmap (NULL, size,
|
||||
PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE,
|
||||
-1, 0);
|
||||
if (fptr_table == MAP_FAILED)
|
||||
_dl_signal_error (errno, NULL, NULL,
|
||||
N_("cannot map pages for fptr table"));
|
||||
|
||||
if (COMPARE_AND_SWAP ((ElfW(Addr) *) &map->l_mach.fptr_table,
|
||||
(ElfW(Addr)) NULL, (ElfW(Addr)) fptr_table))
|
||||
map->l_mach.fptr_table_len = len;
|
||||
else
|
||||
__munmap (fptr_table, len * sizeof (fptr_table[0]));
|
||||
|
||||
return map->l_mach.fptr_table;
|
||||
}
|
||||
|
||||
|
||||
ElfW(Addr)
|
||||
_dl_make_fptr (struct link_map *map, const ElfW(Sym) *sym,
|
||||
ElfW(Addr) ip)
|
||||
{
|
||||
ElfW(Addr) *ftab = map->l_mach.fptr_table;
|
||||
const ElfW(Sym) *symtab;
|
||||
Elf_Symndx symidx;
|
||||
struct local *l;
|
||||
|
||||
if (__glibc_unlikely (ftab == NULL))
|
||||
ftab = make_fptr_table (map);
|
||||
|
||||
symtab = (const void *) D_PTR (map, l_info[DT_SYMTAB]);
|
||||
symidx = sym - symtab;
|
||||
|
||||
if (symidx >= map->l_mach.fptr_table_len)
|
||||
_dl_signal_error (0, NULL, NULL,
|
||||
N_("internal error: symidx out of range of fptr table"));
|
||||
|
||||
while (ftab[symidx] == 0)
|
||||
{
|
||||
/* GOT has already been relocated in elf_get_dynamic_info -
|
||||
don't try to relocate it again. */
|
||||
ElfW(Addr) fdesc
|
||||
= make_fdesc (ip, map->l_info[DT_PLTGOT]->d_un.d_ptr);
|
||||
|
||||
if (__builtin_expect (COMPARE_AND_SWAP (&ftab[symidx], (ElfW(Addr)) NULL,
|
||||
fdesc), 1))
|
||||
{
|
||||
/* No one has updated the entry and the new function
|
||||
descriptor has been installed. */
|
||||
#if 0
|
||||
const char *strtab
|
||||
= (const void *) D_PTR (map, l_info[DT_STRTAB]);
|
||||
|
||||
ELF_MACHINE_LOAD_ADDRESS (l, local);
|
||||
if (l->root != &l->boot_table
|
||||
|| l->boot_table.first_unused > 20)
|
||||
_dl_debug_printf ("created fdesc symbol `%s' at %lx\n",
|
||||
strtab + sym->st_name, ftab[symidx]);
|
||||
#endif
|
||||
break;
|
||||
}
|
||||
else
|
||||
{
|
||||
/* We created a duplicated function descriptor. We put it on
|
||||
free-list. */
|
||||
struct fdesc *f = (struct fdesc *) fdesc;
|
||||
|
||||
ELF_MACHINE_LOAD_ADDRESS (l, local);
|
||||
|
||||
do
|
||||
f->ip = (ElfW(Addr)) l->free_list;
|
||||
while (! COMPARE_AND_SWAP ((ElfW(Addr) *) &l->free_list,
|
||||
f->ip, fdesc));
|
||||
}
|
||||
}
|
||||
|
||||
return ftab[symidx];
|
||||
}
|
||||
|
||||
|
||||
void
|
||||
_dl_unmap (struct link_map *map)
|
||||
{
|
||||
ElfW(Addr) *ftab = map->l_mach.fptr_table;
|
||||
struct fdesc *head = NULL, *tail = NULL;
|
||||
size_t i;
|
||||
|
||||
_dl_unmap_segments (map);
|
||||
|
||||
if (ftab == NULL)
|
||||
return;
|
||||
|
||||
/* String together the fdesc structures that are being freed. */
|
||||
for (i = 0; i < map->l_mach.fptr_table_len; ++i)
|
||||
{
|
||||
if (ftab[i])
|
||||
{
|
||||
*(struct fdesc **) ftab[i] = head;
|
||||
head = (struct fdesc *) ftab[i];
|
||||
if (tail == NULL)
|
||||
tail = head;
|
||||
}
|
||||
}
|
||||
|
||||
/* Prepend the new list to the free_list: */
|
||||
if (tail)
|
||||
do
|
||||
tail->ip = (ElfW(Addr)) local.free_list;
|
||||
while (! COMPARE_AND_SWAP ((ElfW(Addr) *) &local.free_list,
|
||||
tail->ip, (ElfW(Addr)) head));
|
||||
|
||||
__munmap (ftab, (map->l_mach.fptr_table_len
|
||||
* sizeof (map->l_mach.fptr_table[0])));
|
||||
|
||||
map->l_mach.fptr_table = NULL;
|
||||
}
|
||||
|
||||
|
||||
ElfW(Addr)
|
||||
_dl_lookup_address (const void *address)
|
||||
{
|
||||
ElfW(Addr) addr = (ElfW(Addr)) address;
|
||||
struct fdesc_table *t;
|
||||
unsigned long int i;
|
||||
|
||||
for (t = local.root; t != NULL; t = t->next)
|
||||
{
|
||||
i = (struct fdesc *) addr - &t->fdesc[0];
|
||||
if (i < t->first_unused && addr == (ElfW(Addr)) &t->fdesc[i])
|
||||
{
|
||||
addr = t->fdesc[i].ip;
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
return addr;
|
||||
}
|
||||
@ -1,33 +0,0 @@
|
||||
/* Get the symbol address. Generic version.
|
||||
Copyright (C) 1999-2024 Free Software Foundation, Inc.
|
||||
This file is part of the GNU C Library.
|
||||
|
||||
The GNU C Library is free software; you can redistribute it and/or
|
||||
modify it under the terms of the GNU Lesser General Public
|
||||
License as published by the Free Software Foundation; either
|
||||
version 2.1 of the License, or (at your option) any later version.
|
||||
|
||||
The GNU C Library 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
|
||||
Lesser General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU Lesser General Public
|
||||
License along with the GNU C Library; if not, see
|
||||
<https://www.gnu.org/licenses/>. */
|
||||
|
||||
#include <ldsodefs.h>
|
||||
#include <dl-fptr.h>
|
||||
|
||||
void *
|
||||
_dl_symbol_address (struct link_map *map, const ElfW(Sym) *ref)
|
||||
{
|
||||
ElfW(Addr) value = SYMBOL_ADDRESS (map, ref, false);
|
||||
|
||||
/* Return the pointer to function descriptor. */
|
||||
if (ELFW(ST_TYPE) (ref->st_info) == STT_FUNC)
|
||||
return (void *) _dl_make_fptr (map, ref, value);
|
||||
else
|
||||
return (void *) value;
|
||||
}
|
||||
rtld_hidden_def (_dl_symbol_address)
|
||||
@ -1,45 +0,0 @@
|
||||
/* Function descriptors. Generic version.
|
||||
Copyright (C) 1995-2024 Free Software Foundation, Inc.
|
||||
This file is part of the GNU C Library.
|
||||
|
||||
The GNU C Library is free software; you can redistribute it and/or
|
||||
modify it under the terms of the GNU Lesser General Public
|
||||
License as published by the Free Software Foundation; either
|
||||
version 2.1 of the License, or (at your option) any later version.
|
||||
|
||||
The GNU C Library 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
|
||||
Lesser General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU Lesser General Public
|
||||
License along with the GNU C Library; if not, see
|
||||
<https://www.gnu.org/licenses/>. */
|
||||
|
||||
#ifndef dl_fptr_h
|
||||
#define dl_fptr_h 1
|
||||
|
||||
/* An FDESC is a function descriptor. */
|
||||
|
||||
struct fdesc
|
||||
{
|
||||
ElfW(Addr) ip; /* code entry point */
|
||||
ElfW(Addr) gp; /* global pointer */
|
||||
};
|
||||
|
||||
struct fdesc_table
|
||||
{
|
||||
struct fdesc_table *next;
|
||||
unsigned int len; /* # of entries in fdesc table */
|
||||
volatile unsigned int first_unused; /* index of first available entry */
|
||||
struct fdesc fdesc[0];
|
||||
};
|
||||
|
||||
struct link_map;
|
||||
|
||||
extern ElfW(Addr) _dl_boot_fptr_table [];
|
||||
|
||||
extern ElfW(Addr) _dl_make_fptr (struct link_map *, const ElfW(Sym) *,
|
||||
ElfW(Addr));
|
||||
|
||||
#endif /* !dl_fptr_h */
|
||||
@ -19,7 +19,28 @@
|
||||
#ifndef dl_hppa_fptr_h
|
||||
#define dl_hppa_fptr_h 1
|
||||
|
||||
#include <sysdeps/generic/dl-fptr.h>
|
||||
/* An FDESC is a function descriptor. */
|
||||
|
||||
struct fdesc
|
||||
{
|
||||
ElfW(Addr) ip; /* code entry point */
|
||||
ElfW(Addr) gp; /* global pointer */
|
||||
};
|
||||
|
||||
struct fdesc_table
|
||||
{
|
||||
struct fdesc_table *next;
|
||||
unsigned int len; /* # of entries in fdesc table */
|
||||
volatile unsigned int first_unused; /* index of first available entry */
|
||||
struct fdesc fdesc[0];
|
||||
};
|
||||
|
||||
struct link_map;
|
||||
|
||||
extern ElfW(Addr) _dl_boot_fptr_table [];
|
||||
|
||||
extern ElfW(Addr) _dl_make_fptr (struct link_map *, const ElfW(Sym) *,
|
||||
ElfW(Addr));
|
||||
|
||||
/* Initialize function pointer code. Call before relocation processing. */
|
||||
extern void _dl_fptr_init (void);
|
||||
|
||||
Loading…
Reference in New Issue
Block a user