Module Name: src
Committed By: reinoud
Date: Sun Jul 7 19:31:26 UTC 2013
Modified Files:
src/sys/kern: vfs_dirhash.c
src/sys/sys: dirhash.h
Log Message:
Extend generic dirhash to include an empty directory checker based on
the knowledge the dirhash has. This is done by keeping a count of the current
hash entries.
To generate a diff of this commit:
cvs rdiff -u -r1.10 -r1.11 src/sys/kern/vfs_dirhash.c
cvs rdiff -u -r1.5 -r1.6 src/sys/sys/dirhash.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/kern/vfs_dirhash.c
diff -u src/sys/kern/vfs_dirhash.c:1.10 src/sys/kern/vfs_dirhash.c:1.11
--- src/sys/kern/vfs_dirhash.c:1.10 Fri Feb 6 23:56:26 2009
+++ src/sys/kern/vfs_dirhash.c Sun Jul 7 19:31:26 2013
@@ -1,4 +1,4 @@
-/* $NetBSD: vfs_dirhash.c,v 1.10 2009/02/06 23:56:26 enami Exp $ */
+/* $NetBSD: vfs_dirhash.c,v 1.11 2013/07/07 19:31:26 reinoud Exp $ */
/*
* Copyright (c) 2008 Reinoud Zandijk
@@ -28,7 +28,7 @@
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vfs_dirhash.c,v 1.10 2009/02/06 23:56:26 enami Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vfs_dirhash.c,v 1.11 2013/07/07 19:31:26 reinoud Exp $");
/* CLEAN UP! */
#include <sys/param.h>
@@ -165,6 +165,7 @@ dirhash_purge_entries(struct dirhash *di
dirh->flags &= ~DIRH_COMPLETE;
dirh->flags |= DIRH_PURGED;
+ dirh->num_files = 0;
dirhashsize -= dirh->size;
dirh->size = 0;
@@ -309,6 +310,7 @@ dirhash_enter(struct dirhash *dirh,
dirh_e->entry_size = entry_size;
dirh->size += sizeof(struct dirhash_entry);
+ dirh->num_files++;
dirhashsize += sizeof(struct dirhash_entry);
LIST_INSERT_HEAD(&dirh->entries[hashline], dirh_e, next);
}
@@ -378,6 +380,8 @@ dirhash_remove(struct dirhash *dirh, str
KASSERT(dirh_e->entry_size == entry_size);
LIST_REMOVE(dirh_e, next);
dirh->size -= sizeof(struct dirhash_entry);
+ KASSERT(dirh->num_files > 0);
+ dirh->num_files--;
dirhashsize -= sizeof(struct dirhash_entry);
dirhash_enter_freed(dirh, offset, entry_size);
@@ -469,3 +473,33 @@ dirhash_lookup_freed(struct dirhash *dir
*result = NULL;
return 0;
}
+
+
+bool
+dirhash_dir_isempty(struct dirhash *dirh)
+{
+#ifdef DEBUG
+ struct dirhash_entry *dirh_e;
+ int hashline, num;
+
+ num = 0;
+ for (hashline = 0; hashline < DIRHASH_HASHSIZE; hashline++) {
+ LIST_FOREACH(dirh_e, &dirh->entries[hashline], next) {
+ num++;
+ }
+ }
+
+ if (dirh->num_files != num) {
+ printf("dirhash_dir_isempy: dirhash_counter failed: "
+ "dirh->num_files = %d, counted %d\n",
+ dirh->num_files, num);
+ assert(dirh->num_files == num);
+ }
+#endif
+ /* assert the directory hash info is valid */
+ KASSERT(dirh->flags & DIRH_COMPLETE);
+
+ /* the directory is empty when only '..' lifes in it or is absent */
+ return (dirh->num_files <= 1);
+}
+
Index: src/sys/sys/dirhash.h
diff -u src/sys/sys/dirhash.h:1.5 src/sys/sys/dirhash.h:1.6
--- src/sys/sys/dirhash.h:1.5 Sun Sep 27 21:50:48 2009
+++ src/sys/sys/dirhash.h Sun Jul 7 19:31:26 2013
@@ -1,4 +1,4 @@
-/* $NetBSD: dirhash.h,v 1.5 2009/09/27 21:50:48 reinoud Exp $ */
+/* $NetBSD: dirhash.h,v 1.6 2013/07/07 19:31:26 reinoud Exp $ */
/*
* Copyright (c) 2008 Reinoud Zandijk
@@ -52,6 +52,7 @@ struct dirhash {
uint32_t flags;
uint32_t size; /* in bytes */
uint32_t refcnt;
+ uint32_t num_files;
LIST_HEAD(, dirhash_entry) entries[DIRHASH_HASHSIZE];
LIST_HEAD(, dirhash_entry) free_entries;
TAILQ_ENTRY(dirhash) next;
@@ -79,5 +80,6 @@ int dirhash_lookup(struct dirhash *, con
struct dirhash_entry **);
int dirhash_lookup_freed(struct dirhash *, uint32_t,
struct dirhash_entry **);
+bool dirhash_dir_isempty(struct dirhash *dirh);
#endif /* _SYS_DIRHASH_H_ */
