ldso/: tls support for dynamic linker

Signed-off-by: Austin Foxley <austinf@cetoncorp.com>

1 files changed, 147 insertions, 0 deletions

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 <bits/kernel-features.h>
+
+#include <features.h>
+#include <tls.h>
+
+#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