Add MAP_NOCORE to mmap(2), and MADV_NOCORE and MADV_CORE to madvise(2).

This
This feature allows you to specify if mmap'd data is included in
an application's corefile.

Change the type of eflags in struct vm_map_entry from u_char to
vm_eflags_t (an unsigned int).

Reviewed by:	dillon,jdp,alfred
Approved by:	jkh

3 files changed, 37 insertions, 20 deletions

diff --git a/sys/vm/vm_map.c b/sys/vm/vm_map.c
index 7acaa51..835ed15 100644
--- a/sys/vm/vm_map.c
+++ b/sys/vm/vm_map.c
@@ -427,7 +427,7 @@ vm_map_insert(vm_map_t map, vm_object_t object, vm_ooffset_t offset,
 	vm_map_entry_t new_entry;
 	vm_map_entry_t prev_entry;
 	vm_map_entry_t temp_entry;
-	u_char protoeflags;
+	vm_eflags_t protoeflags;
 
 	/*
 	 * Check that the start and end points are not bogus.
@@ -468,6 +468,8 @@ vm_map_insert(vm_map_t map, vm_object_t object, vm_ooffset_t offset,
 	}
 	if (cow & MAP_DISABLE_SYNCER)
 		protoeflags |= MAP_ENTRY_NOSYNC;
+	if (cow & MAP_DISABLE_COREDUMP)
+		protoeflags |= MAP_ENTRY_NOCOREDUMP;
 
 	if (object) {
 		/*
@@ -1039,6 +1041,8 @@ vm_map_madvise(map, start, end, behav)
 	case MADV_RANDOM:
 	case MADV_NOSYNC:
 	case MADV_AUTOSYNC:
+	case MADV_NOCORE:
+	case MADV_CORE:
 		modify_map = 1;
 		vm_map_lock(map);
 		break;
@@ -1096,6 +1100,12 @@ vm_map_madvise(map, start, end, behav)
 			case MADV_AUTOSYNC:
 				current->eflags &= ~MAP_ENTRY_NOSYNC;
 				break;
+			case MADV_NOCORE:
+				current->eflags |= MAP_ENTRY_NOCOREDUMP;
+				break;
+			case MADV_CORE:
+				current->eflags &= ~MAP_ENTRY_NOCOREDUMP;
+				break;
 			default:
 				break;
 			}
diff --git a/sys/vm/vm_map.h b/sys/vm/vm_map.h
index 43412cf..f290b2c 100644
--- a/sys/vm/vm_map.h
+++ b/sys/vm/vm_map.h
@@ -78,6 +78,8 @@
  *	vm_map_entry_t		an entry in an address map.
  */
 
+typedef u_int vm_eflags_t;
+
 /*
  *	Objects which live in maps may be either VM objects, or
  *	another map (called a "sharing map") which denotes read-write
@@ -103,7 +105,7 @@ struct vm_map_entry {
 	vm_offset_t avail_ssize;	/* amt can grow if this is a stack */
 	union vm_map_object object;	/* object I point to */
 	vm_ooffset_t offset;		/* offset into object */
-	u_char eflags;			/* map entry flags */
+	vm_eflags_t eflags;		/* map entry flags */
 	/* Only in task maps: */
 	vm_prot_t protection;		/* protection code */
 	vm_prot_t max_protection;	/* maximum protection */
@@ -112,19 +114,21 @@ struct vm_map_entry {
 	vm_pindex_t lastr;		/* last read */
 };
 
-#define MAP_ENTRY_NOSYNC		0x1
-#define MAP_ENTRY_IS_SUB_MAP		0x2
-#define MAP_ENTRY_COW			0x4
-#define MAP_ENTRY_NEEDS_COPY		0x8
-#define MAP_ENTRY_NOFAULT		0x10
-#define MAP_ENTRY_USER_WIRED		0x20
+#define MAP_ENTRY_NOSYNC		0x0001
+#define MAP_ENTRY_IS_SUB_MAP		0x0002
+#define MAP_ENTRY_COW			0x0004
+#define MAP_ENTRY_NEEDS_COPY		0x0008
+#define MAP_ENTRY_NOFAULT		0x0010
+#define MAP_ENTRY_USER_WIRED		0x0020
+
+#define MAP_ENTRY_BEHAV_NORMAL		0x0000	/* default behavior */
+#define MAP_ENTRY_BEHAV_SEQUENTIAL	0x0040	/* expect sequential access */
+#define MAP_ENTRY_BEHAV_RANDOM		0x0080	/* expect random access */
+#define MAP_ENTRY_BEHAV_RESERVED	0x00C0	/* future use */
 
-#define MAP_ENTRY_BEHAV_NORMAL		0x00	/* default behavior */
-#define MAP_ENTRY_BEHAV_SEQUENTIAL	0x40	/* expect sequential access */
-#define MAP_ENTRY_BEHAV_RANDOM		0x80	/* expect random access */
-#define MAP_ENTRY_BEHAV_RESERVED	0xC0	/* future use */
+#define MAP_ENTRY_BEHAV_MASK		0x00C0
 
-#define MAP_ENTRY_BEHAV_MASK		0xC0
+#define MAP_ENTRY_NOCOREDUMP		0x0400	/* don't include in a core */
 
 static __inline u_char   
 vm_map_entry_behavior(struct vm_map_entry *entry)
@@ -324,12 +328,13 @@ vmspace_resident_count(struct vmspace *vmspace)
 /*
  * Copy-on-write flags for vm_map operations
  */
-#define MAP_UNUSED_01		0x1
-#define MAP_COPY_ON_WRITE	0x2
-#define MAP_NOFAULT		0x4
-#define MAP_PREFAULT		0x8
-#define MAP_PREFAULT_PARTIAL	0x10
-#define MAP_DISABLE_SYNCER	0x20
+#define MAP_UNUSED_01		0x0001
+#define MAP_COPY_ON_WRITE	0x0002
+#define MAP_NOFAULT		0x0004
+#define MAP_PREFAULT		0x0008
+#define MAP_PREFAULT_PARTIAL	0x0010
+#define MAP_DISABLE_SYNCER	0x0020
+#define MAP_DISABLE_COREDUMP	0x0100
 
 /*
  * vm_fault option flags
diff --git a/sys/vm/vm_mmap.c b/sys/vm/vm_mmap.c
index b42239c..53462f4 100644
--- a/sys/vm/vm_mmap.c
+++ b/sys/vm/vm_mmap.c
@@ -664,7 +664,7 @@ madvise(p, uap)
 	/*
 	 * Check for illegal behavior
 	 */
-	if (uap->behav < 0 || uap->behav > MADV_AUTOSYNC)
+	if (uap->behav < 0 || uap->behav > MADV_CORE)
 		return (EINVAL);
 	/*
 	 * Check for illegal addresses.  Watch out for address wrap... Note
@@ -1095,6 +1095,8 @@ vm_mmap(vm_map_t map, vm_offset_t *addr, vm_size_t size, vm_prot_t prot,
 		docow |= MAP_COPY_ON_WRITE;
 	if (flags & MAP_NOSYNC)
 		docow |= MAP_DISABLE_SYNCER;
+	if (flags & MAP_NOCORE)
+		docow |= MAP_DISABLE_COREDUMP;
 
 #if defined(VM_PROT_READ_IS_EXEC)
 	if (prot & VM_PROT_READ)