Add two hooks to signal module load and module unload to MD code.

The primary reason for this is to allow MD code to process machine
specific attributes, segments or sections in the ELF file and
update machine specific state accordingly. An immediate use of this
is in the ia64 port where unwind information is updated to allow
debugging and tracing in/across modules. Note that this commit
does not add the functionality to the ia64 port. See revision 1.9
of ia64/ia64/elf_machdep.c.

Validated on: alpha, i386, ia64

1 files changed, 9 insertions, 0 deletions

diff --git a/sys/kern/link_elf.c b/sys/kern/link_elf.c
index bbbaa2ca3275..75c95cda179c 100644
--- a/sys/kern/link_elf.c
+++ b/sys/kern/link_elf.c
@@ -222,6 +222,12 @@ link_elf_link_common_finish(linker_file_t lf)
     elf_file_t ef = (elf_file_t)lf;
     char *newfilename;
 #endif
+    int error;
+
+    /* Notify MD code that a module is being loaded. */
+    error = elf_cpu_load_file(lf);
+    if (error)
+	return (error);
 
 #ifdef DDB
     GDB_STATE(RT_ADD);
@@ -838,6 +844,9 @@ link_elf_unload_file(linker_file_t file)
     }
 #endif
 
+    /* Notify MD code that a module is being unloaded. */
+    elf_cpu_unload_file(file);
+
     if (ef->preloaded) {
 	link_elf_unload_preload(file);
 	return;