From 1aeb23cdfad85fbb0905ff47a30c712552253c46 Mon Sep 17 00:00:00 2001
From: Marcel Moolenaar <marcel@FreeBSD.org>
Date: Sat, 19 Oct 2002 19:16:03 +0000
Subject: [PATCH] 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
---
 sys/alpha/alpha/elf_machdep.c     | 14 ++++++++++++++
 sys/amd64/amd64/elf_machdep.c     | 14 ++++++++++++++
 sys/i386/i386/elf_machdep.c       | 14 ++++++++++++++
 sys/ia64/ia64/elf_machdep.c       | 15 +++++++++++++++
 sys/kern/link_elf.c               |  9 +++++++++
 sys/kern/link_elf_obj.c           |  9 +++++++++
 sys/powerpc/powerpc/elf_machdep.c | 14 ++++++++++++++
 sys/sparc64/sparc64/elf_machdep.c | 14 ++++++++++++++
 sys/sys/linker.h                  |  3 +++
 9 files changed, 106 insertions(+)

diff --git a/sys/alpha/alpha/elf_machdep.c b/sys/alpha/alpha/elf_machdep.c
index ddeae1ba561b..285a17441290 100644
--- a/sys/alpha/alpha/elf_machdep.c
+++ b/sys/alpha/alpha/elf_machdep.c
@@ -172,3 +172,17 @@ elf_reloc(linker_file_t lf, const void *data, int type)
 	}
 	return(0);
 }
+
+int
+elf_cpu_load_file(linker_file_t lf __unused)
+{
+
+	return (0);
+}
+
+int
+elf_cpu_unload_file(linker_file_t lf __unused)
+{
+
+	return (0);
+}
diff --git a/sys/amd64/amd64/elf_machdep.c b/sys/amd64/amd64/elf_machdep.c
index 619b0777ab9c..71520de1747a 100644
--- a/sys/amd64/amd64/elf_machdep.c
+++ b/sys/amd64/amd64/elf_machdep.c
@@ -169,3 +169,17 @@ elf_reloc(linker_file_t lf, const void *data, int type)
 	}
 	return(0);
 }
+
+int
+elf_cpu_load_file(linker_file_t lf __unused)
+{
+
+	return (0);
+}
+
+int
+elf_cpu_unload_file(linker_file_t lf __unused)
+{
+
+	return (0);
+}
diff --git a/sys/i386/i386/elf_machdep.c b/sys/i386/i386/elf_machdep.c
index 619b0777ab9c..71520de1747a 100644
--- a/sys/i386/i386/elf_machdep.c
+++ b/sys/i386/i386/elf_machdep.c
@@ -169,3 +169,17 @@ elf_reloc(linker_file_t lf, const void *data, int type)
 	}
 	return(0);
 }
+
+int
+elf_cpu_load_file(linker_file_t lf __unused)
+{
+
+	return (0);
+}
+
+int
+elf_cpu_unload_file(linker_file_t lf __unused)
+{
+
+	return (0);
+}
diff --git a/sys/ia64/ia64/elf_machdep.c b/sys/ia64/ia64/elf_machdep.c
index 5b2bc2eec3a1..ea8695fda0a7 100644
--- a/sys/ia64/ia64/elf_machdep.c
+++ b/sys/ia64/ia64/elf_machdep.c
@@ -46,6 +46,7 @@
 
 #include <machine/elf.h>
 #include <machine/md_var.h>
+#include <machine/unwind.h>
 
 struct sysentvec elf64_freebsd_sysvec = {
 	SYS_MAXSYSCALL,
@@ -215,3 +216,17 @@ elf_reloc(linker_file_t lf, const void *data, int type)
 
 	return (0);
 }
+
+int
+elf_cpu_load_file(linker_file_t lf __unused)
+{
+
+	return (0);
+}
+
+int
+elf_cpu_unload_file(linker_file_t lf __unused)
+{
+
+	return (0);
+}
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;
diff --git a/sys/kern/link_elf_obj.c b/sys/kern/link_elf_obj.c
index bbbaa2ca3275..75c95cda179c 100644
--- a/sys/kern/link_elf_obj.c
+++ b/sys/kern/link_elf_obj.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;
diff --git a/sys/powerpc/powerpc/elf_machdep.c b/sys/powerpc/powerpc/elf_machdep.c
index c1627b1b9f8a..e00c9d385363 100644
--- a/sys/powerpc/powerpc/elf_machdep.c
+++ b/sys/powerpc/powerpc/elf_machdep.c
@@ -163,3 +163,17 @@ elf_reloc(linker_file_t lf, const void *data, int type)
 	}
 	return(0);
 }
+
+int
+elf_cpu_load_file(linker_file_t lf __unused)
+{
+
+	return (0);
+}
+
+int
+elf_cpu_unload_file(linker_file_t lf __unused)
+{
+
+	return (0);
+}
diff --git a/sys/sparc64/sparc64/elf_machdep.c b/sys/sparc64/sparc64/elf_machdep.c
index 4889bc9ab881..e4860c857de1 100644
--- a/sys/sparc64/sparc64/elf_machdep.c
+++ b/sys/sparc64/sparc64/elf_machdep.c
@@ -312,3 +312,17 @@ elf_reloc(linker_file_t lf, const void *data, int type)
 
 	return (0);
 }
+
+int
+elf_cpu_load_file(linker_file_t lf __unused)
+{
+
+	return (0);
+}
+
+int
+elf_cpu_unload_file(linker_file_t lf __unused)
+{
+
+	return (0);
+}
diff --git a/sys/sys/linker.h b/sys/sys/linker.h
index d15a3872e53a..5e0a76050d34 100644
--- a/sys/sys/linker.h
+++ b/sys/sys/linker.h
@@ -233,6 +233,9 @@ Elf_Addr elf_lookup(linker_file_t, Elf_Word, int);
 const Elf_Sym *elf_get_sym(linker_file_t _lf, Elf_Word _symidx);
 const char *elf_get_symname(linker_file_t _lf, Elf_Word _symidx);
 
+int elf_cpu_load_file(linker_file_t);
+int elf_cpu_unload_file(linker_file_t);
+
 /* values for type */
 #define ELF_RELOC_REL	1
 #define ELF_RELOC_RELA	2