From 534661b91c98492995274c364c8177c45efc63db Mon Sep 17 00:00:00 2001 From: Austin Foxley Date: Sat, 19 Sep 2009 10:04:05 -0700 Subject: ldso/: tls support for dynamic linker Signed-off-by: Austin Foxley --- ldso/include/ldsodefs.h | 147 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 147 insertions(+) create mode 100644 ldso/include/ldsodefs.h (limited to 'ldso/include/ldsodefs.h') diff --git a/ldso/include/ldsodefs.h b/ldso/include/ldsodefs.h new file mode 100644 index 000000000..432c7b848 --- /dev/null +++ b/ldso/include/ldsodefs.h @@ -0,0 +1,147 @@ +#ifndef _LDSODEFS_H +#define _LDSODEFS_H 1 + +#include + +#include +#include + +#ifdef __mips__ +/* The MIPS ABI specifies that the dynamic section has to be read-only. */ + +#define DL_RO_DYN_SECTION 1 + +/* TODO: Import in 64-bit relocations from glibc. */ +#endif + +#ifndef SHARED +# define EXTERN extern +#else +# ifdef IS_IN_rtld +# define EXTERN +# else +# define EXTERN extern +# endif +#endif + +/* Non-shared code has no support for multiple namespaces. */ +#ifdef SHARED +# define DL_NNS 16 +#else +# define DL_NNS 1 +#endif + +#define GL(x) _##x +#define GLRO(x) _##x + +/* Variable pointing to the end of the stack (or close to it). This value + must be constant over the runtime of the application. Some programs + might use the variable which results in copy relocations on some + platforms. But this does not matter, ld.so can always use the local + copy. */ +extern void *__libc_stack_end; + +/* Determine next available module ID. */ +extern size_t _dl_next_tls_modid (void) internal_function attribute_hidden; + +/* Calculate offset of the TLS blocks in the static TLS block. */ +extern void _dl_determine_tlsoffset (void) internal_function attribute_hidden; + +/* Set up the data structures for TLS, when they were not set up at startup. + Returns nonzero on malloc failure. + This is called from _dl_map_object_from_fd or by libpthread. */ +extern int _dl_tls_setup (void) internal_function; +rtld_hidden_proto (_dl_tls_setup) + +/* Allocate memory for static TLS block (unless MEM is nonzero) and dtv. */ +extern void *_dl_allocate_tls (void *mem) internal_function; + +/* Get size and alignment requirements of the static TLS block. */ +extern void _dl_get_tls_static_info (size_t *sizep, size_t *alignp) + internal_function; + +extern void _dl_allocate_static_tls (struct link_map *map) + internal_function attribute_hidden; + +/* Taken from glibc/elf/dl-reloc.c */ +#define CHECK_STATIC_TLS(sym_map) \ + do { \ + if (__builtin_expect ((sym_map)->l_tls_offset == NO_TLS_OFFSET, 0)) \ + _dl_allocate_static_tls (sym_map); \ + } while (0) + +/* These are internal entry points to the two halves of _dl_allocate_tls, + only used within rtld.c itself at startup time. */ +extern void *_dl_allocate_tls_storage (void) + internal_function attribute_hidden; +extern void *_dl_allocate_tls_init (void *) internal_function; + +/* Deallocate memory allocated with _dl_allocate_tls. */ +extern void _dl_deallocate_tls (void *tcb, bool dealloc_tcb) internal_function; + +extern void _dl_nothread_init_static_tls (struct link_map *) internal_function attribute_hidden; + +/* Highest dtv index currently needed. */ +EXTERN size_t _dl_tls_max_dtv_idx; +/* Flag signalling whether there are gaps in the module ID allocation. */ +EXTERN bool _dl_tls_dtv_gaps; +/* Information about the dtv slots. */ +EXTERN struct dtv_slotinfo_list +{ + size_t len; + struct dtv_slotinfo_list *next; + struct dtv_slotinfo + { + size_t gen; + bool is_static; + struct link_map *map; + } slotinfo[0]; +} *_dl_tls_dtv_slotinfo_list; +/* Number of modules in the static TLS block. */ +EXTERN size_t _dl_tls_static_nelem; +/* Size of the static TLS block. */ +EXTERN size_t _dl_tls_static_size; +/* Size actually allocated in the static TLS block. */ +EXTERN size_t _dl_tls_static_used; +/* Alignment requirement of the static TLS block. */ +EXTERN size_t _dl_tls_static_align; +/* Function pointer for catching TLS errors. */ +EXTERN void **(*_dl_error_catch_tsd) (void) __attribute__ ((const)); + +/* Number of additional entries in the slotinfo array of each slotinfo + list element. A large number makes it almost certain take we never + have to iterate beyond the first element in the slotinfo list. */ +# define TLS_SLOTINFO_SURPLUS (62) + +/* Number of additional slots in the dtv allocated. */ +# define DTV_SURPLUS (14) + + /* Initial dtv of the main thread, not allocated with normal malloc. */ + EXTERN void *_dl_initial_dtv; + /* Generation counter for the dtv. */ + EXTERN size_t _dl_tls_generation; + + EXTERN void (*_dl_init_static_tls) (struct link_map *); + +/* We have the auxiliary vector. */ +#define HAVE_AUX_VECTOR + +/* We can assume that the kernel always provides the AT_UID, AT_EUID, + AT_GID, and AT_EGID values in the auxiliary vector from 2.4.0 or so on. */ +#if __ASSUME_AT_XID +# define HAVE_AUX_XID +#endif + +/* We can assume that the kernel always provides the AT_SECURE value + in the auxiliary vector from 2.5.74 or so on. */ +#if __ASSUME_AT_SECURE +# define HAVE_AUX_SECURE +#endif + +/* Starting with one of the 2.4.0 pre-releases the Linux kernel passes + up the page size information. */ +#if __ASSUME_AT_PAGESIZE +# define HAVE_AUX_PAGESIZE +#endif + +#endif -- cgit v1.2.3