With Alfred's permission, remove vm_mtx in favor of a fine-grained approach

(this commit is just the first stage).  Also add various GIANT_ macros to
formalize the removal of Giant, making it easy to test in a more piecemeal
fashion. These macros will allow us to test fine-grained locks to a degree
before removing Giant, and also after, and to remove Giant in a piecemeal
fashion via sysctl's on those subsystems which the authors believe can
operate without Giant.

1 files changed, 2 insertions, 8 deletions

diff --git a/sys/kern/link_elf_obj.c b/sys/kern/link_elf_obj.c
index da7462a..439b9de 100644
--- a/sys/kern/link_elf_obj.c
+++ b/sys/kern/link_elf_obj.c
@@ -531,6 +531,8 @@ link_elf_load_file(linker_class_t cls, const char* filename, linker_file_t* resu
     int symcnt;
     int strcnt;
 
+    GIANT_REQUIRED;
+
     shdr = NULL;
     lf = NULL;
 
@@ -657,10 +659,8 @@ link_elf_load_file(linker_class_t cls, const char* filename, linker_file_t* resu
 
     ef = (elf_file_t) lf;
 #ifdef SPARSE_MAPPING
-    mtx_lock(&vm_mtx);
     ef->object = vm_object_allocate(OBJT_DEFAULT, mapsize >> PAGE_SHIFT);
     if (ef->object == NULL) {
-    	mtx_unlock(&vm_mtx);
 	free(ef, M_LINKER);
 	error = ENOMEM;
 	goto out;
@@ -673,11 +673,9 @@ link_elf_load_file(linker_class_t cls, const char* filename, linker_file_t* resu
 			VM_PROT_ALL, VM_PROT_ALL, 0);
     if (error) {
 	vm_object_deallocate(ef->object);
-    	mtx_unlock(&vm_mtx);
 	ef->object = 0;
 	goto out;
     }
-    mtx_unlock(&vm_mtx);
 #else
     ef->address = malloc(mapsize, M_LINKER, M_WAITOK);
     if (!ef->address) {
@@ -705,12 +703,10 @@ link_elf_load_file(linker_class_t cls, const char* filename, linker_file_t* resu
 	/*
 	 * Wire down the pages
 	 */
-	mtx_lock(&vm_mtx);
 	vm_map_pageable(kernel_map,
 			(vm_offset_t) segbase,
 			(vm_offset_t) segbase + segs[i]->p_memsz,
 			FALSE);
-	mtx_unlock(&vm_mtx);
 #endif
     }
 
@@ -834,12 +830,10 @@ link_elf_unload_file(linker_file_t file)
     }
 #ifdef SPARSE_MAPPING
     if (ef->object) {
-	mtx_lock(&vm_mtx);	    
 	vm_map_remove(kernel_map, (vm_offset_t) ef->address,
 		      (vm_offset_t) ef->address
 		      + (ef->object->size << PAGE_SHIFT));
 	vm_object_deallocate(ef->object);
-	mtx_unlock(&vm_mtx);	    
     }
 #else
     if (ef->address)