mirror of
https://sourceware.org/git/glibc.git
synced 2025-10-31 22:10:34 +03:00
126 lines
3.5 KiB
C
126 lines
3.5 KiB
C
/* Hash table for TLS descriptors.
|
|
Copyright (C) 2005-2025 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 TLSDESCHTAB_H
|
|
# define TLSDESCHTAB_H 1
|
|
|
|
#include <atomic.h>
|
|
|
|
# ifdef SHARED
|
|
|
|
# include <inline-hashtab.h>
|
|
|
|
inline static int
|
|
hash_tlsdesc (void *p)
|
|
{
|
|
struct tlsdesc_dynamic_arg *td = p;
|
|
|
|
/* We know all entries are for the same module, so ti_offset is the
|
|
only distinguishing entry. */
|
|
return td->tlsinfo.ti_offset;
|
|
}
|
|
|
|
inline static int
|
|
eq_tlsdesc (void *p, void *q)
|
|
{
|
|
struct tlsdesc_dynamic_arg *tdp = p, *tdq = q;
|
|
|
|
return tdp->tlsinfo.ti_offset == tdq->tlsinfo.ti_offset;
|
|
}
|
|
|
|
inline static size_t
|
|
map_generation (struct link_map *map)
|
|
{
|
|
size_t idx = map->l_tls_modid;
|
|
struct dtv_slotinfo_list *listp = GL(dl_tls_dtv_slotinfo_list);
|
|
|
|
/* Find the place in the dtv slotinfo list. */
|
|
do
|
|
{
|
|
/* Does it fit in the array of this list element? */
|
|
if (idx < listp->len)
|
|
{
|
|
/* We should never get here for a module in static TLS, so
|
|
we can assume that, if the generation count is zero, we
|
|
still haven't determined the generation count for this
|
|
module. */
|
|
if (listp->slotinfo[idx].map == map && listp->slotinfo[idx].gen)
|
|
return listp->slotinfo[idx].gen;
|
|
else
|
|
break;
|
|
}
|
|
idx -= listp->len;
|
|
listp = listp->next;
|
|
}
|
|
while (listp != NULL);
|
|
|
|
/* If we get to this point, the module still hasn't been assigned an
|
|
entry in the dtv slotinfo data structures, and it will when we're
|
|
done with relocations. At that point, the module will get a
|
|
generation number that is one past the current generation, so
|
|
return exactly that. */
|
|
return GL(dl_tls_generation) + 1;
|
|
}
|
|
|
|
/* Returns the data pointer for a given map and tls offset that is used
|
|
to fill in one of the GOT entries referenced by a TLSDESC relocation
|
|
when using dynamic TLS. This requires allocation, returns NULL on
|
|
allocation failure. */
|
|
void *
|
|
_dl_make_tlsdesc_dynamic (struct link_map *map, size_t ti_offset)
|
|
{
|
|
struct hashtab *ht;
|
|
void **entry;
|
|
struct tlsdesc_dynamic_arg *td, test;
|
|
|
|
ht = map->l_mach.tlsdesc_table;
|
|
if (! ht)
|
|
{
|
|
ht = htab_create ();
|
|
if (! ht)
|
|
return NULL;
|
|
map->l_mach.tlsdesc_table = ht;
|
|
}
|
|
|
|
test.tlsinfo.ti_module = map->l_tls_modid;
|
|
test.tlsinfo.ti_offset = ti_offset;
|
|
entry = htab_find_slot (ht, &test, 1, hash_tlsdesc, eq_tlsdesc);
|
|
if (! entry)
|
|
return NULL;
|
|
|
|
if (*entry)
|
|
{
|
|
td = *entry;
|
|
return td;
|
|
}
|
|
|
|
*entry = td = malloc (sizeof (struct tlsdesc_dynamic_arg));
|
|
if (! td)
|
|
return NULL;
|
|
/* This may be higher than the map's generation, but it doesn't
|
|
matter much. Worst case, we'll have one extra DTV update per
|
|
thread. */
|
|
td->gen_count = map_generation (map);
|
|
td->tlsinfo = test.tlsinfo;
|
|
return td;
|
|
}
|
|
|
|
# endif /* SHARED */
|
|
|
|
#endif
|