Blackfin FD-PIC patch 1/6.

Add a new function _dl_free.  In _dl_malloc, ensure we always get back a full
page from mmap.
Reset _dl_malloc_function and _dl_free_function when libdl is initialized.

3 files changed, 43 insertions, 5 deletions

diff --git a/ldso/include/ldso.h b/ldso/include/ldso.h
index 97f54b72c..88c1116e7 100644
--- a/ldso/include/ldso.h
+++ b/ldso/include/ldso.h
@@ -99,7 +99,8 @@ extern int   _dl_debug_file;
 #define NULL ((void *) 0)
 #endif
 
-extern void *_dl_malloc(int size);
+extern void *_dl_malloc(size_t size);
+extern void _dl_free(void *);
 extern char *_dl_getenv(const char *symbol, char **envp);
 extern void _dl_unsetenv(const char *symbol, char **envp);
 extern char *_dl_strdup(const char *string);
diff --git a/ldso/ldso/ldso.c b/ldso/ldso/ldso.c
index 3a5fc14f5..89d9bbd56 100644
--- a/ldso/ldso/ldso.c
+++ b/ldso/ldso/ldso.c
@@ -50,6 +50,7 @@ int _dl_errno                  = 0;	/* We can't use the real errno in ldso */
 size_t _dl_pagesize            = 0;	/* Store the page size for use later */
 struct r_debug *_dl_debug_addr = NULL;	/* Used to communicate with the gdb debugger */
 void *(*_dl_malloc_function) (size_t size) = NULL;
+void (*_dl_free_function) (void *p) = NULL;
 
 #ifdef __SUPPORT_LD_DEBUG__
 char *_dl_debug           = 0;
@@ -884,7 +885,7 @@ static int _dl_suid_ok(void)
 	return 0;
 }
 
-void *_dl_malloc(int size)
+void *_dl_malloc(size_t size)
 {
 	void *retval;
 
@@ -895,9 +896,26 @@ void *_dl_malloc(int size)
 	if (_dl_malloc_function)
 		return (*_dl_malloc_function) (size);
 
-	if (_dl_malloc_addr - _dl_mmap_zero + (unsigned)size > _dl_pagesize) {
+	if (_dl_malloc_addr - _dl_mmap_zero + size > _dl_pagesize) {
+		size_t rounded_size;
+
+		/* Since the above assumes we get a full page even if
+		   we request less than that, make sure we request a
+		   full page, since uClinux may give us less than than
+		   a full page.  We might round even
+		   larger-than-a-page sizes, but we end up never
+		   reusing _dl_mmap_zero/_dl_malloc_addr in that case,
+		   so we don't do it.
+
+		   The actual page size doesn't really matter; as long
+		   as we're self-consistent here, we're safe.  */
+		if (size < _dl_pagesize)
+			rounded_size = (size + _dl_pagesize - 1) & _dl_pagesize;
+		else
+			rounded_size = size;
+
 		_dl_debug_early("mmapping more memory\n");
-		_dl_mmap_zero = _dl_malloc_addr = _dl_mmap((void *) 0, size,
+		_dl_mmap_zero = _dl_malloc_addr = _dl_mmap((void *) 0, rounded_size,
 				PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
 		if (_dl_mmap_check_error(_dl_mmap_zero)) {
 			_dl_dprintf(2, "%s: mmap of a spare page failed!\n", _dl_progname);
@@ -916,5 +934,11 @@ void *_dl_malloc(int size)
 	return retval;
 }
 
+void _dl_free (void *p)
+{
+	if (_dl_free_function)
+		(*_dl_free_function) (p);
+}
+
 #include "dl-hash.c"
 #include "dl-elf.c"
diff --git a/ldso/libdl/libdl.c b/ldso/libdl/libdl.c
index f018c0a0d..f2303c52e 100644
--- a/ldso/libdl/libdl.c
+++ b/ldso/libdl/libdl.c
@@ -32,6 +32,7 @@
 
 #include <ldso.h>
 #include <stdio.h>
+#include <string.h>
 
 
 #ifdef SHARED
@@ -51,6 +52,7 @@ extern struct elf_resolve *_dl_loaded_modules;
 extern struct r_debug *_dl_debug_addr;
 extern unsigned long _dl_error_number;
 extern void *(*_dl_malloc_function)(size_t);
+extern void (*_dl_free_function) (void *p);
 extern void _dl_run_init_array(struct elf_resolve *);
 extern void _dl_run_fini_array(struct elf_resolve *);
 #ifdef __LDSO_CACHE_SUPPORT__
@@ -67,6 +69,9 @@ extern char *_dl_debug;
 
 #else /* SHARED */
 
+#define _dl_malloc malloc
+#define _dl_free free
+
 /* When libdl is linked as a static library, we need to replace all
  * the symbols that otherwise would have been loaded in from ldso... */
 
@@ -83,13 +88,15 @@ char *_dl_debug_bindings  = 0;
 int   _dl_debug_file      = 2;
 #endif
 const char *_dl_progname       = "";        /* Program name */
+void *(*_dl_malloc_function)(size_t);
+void (*_dl_free_function) (void *p);
 char *_dl_library_path         = 0;         /* Where we look for libraries */
 char *_dl_ldsopath             = 0;         /* Location of the shared lib loader */
 int _dl_errno                  = 0;         /* We can't use the real errno in ldso */
 size_t _dl_pagesize            = PAGE_SIZE; /* Store the page size for use later */
 /* This global variable is also to communicate with debuggers such as gdb. */
 struct r_debug *_dl_debug_addr = NULL;
-#define _dl_malloc malloc
+
 #include "../ldso/dl-array.c"
 #include "../ldso/dl-debug.c"
 #include LDSO_ELFINTERP
@@ -157,6 +164,7 @@ void *dlopen(const char *libname, int flag)
 	struct init_fini_list *tmp, *runp, *runp2, *dep_list;
 	unsigned int nlist, i;
 	struct elf_resolve **init_fini_list;
+	static int _dl_init = 0;
 
 	/* A bit of sanity checking... */
 	if (!(flag & (RTLD_LAZY|RTLD_NOW))) {
@@ -166,6 +174,11 @@ void *dlopen(const char *libname, int flag)
 
 	from = (ElfW(Addr)) __builtin_return_address(0);
 
+	if (!_dl_init) {
+		_dl_init++;
+		_dl_malloc_function = malloc;
+		_dl_free_function = free;
+	}
 	/* Cover the trivial case first */
 	if (!libname)
 		return _dl_symbol_tables;