From: Neil Brown <neilb@nbeee.brown>
Date: Mon, 19 Jul 2010 04:57:20 +0000 (+1000)
Subject: Use anon super for prime_sb
X-Git-Url: http://git.neil.brown.name/?a=commitdiff_plain;h=effb90a90cac0661320686cd10887ce697571e60;p=LaFS.git

Use anon super for prime_sb

This is cleaner.

also clean up failure path for lafs_load

Signed-off-by: NeilBrown <neilb@suse.de>
---

diff --git a/super.c b/super.c
index 9b6119f..59a2c08 100644
--- a/super.c
+++ b/super.c
@@ -513,13 +513,9 @@ lafs_load(struct options *op, int newest)
 	err = lafs_segtrack_init(fs->segtrack);
 
 	fs->ss = kzalloc(sizeof(struct snapshot)*fs->maxsnapshot, GFP_KERNEL);
-	if (!fs->ss || !fs->scan.free_usages || err) {
-		kfree(fs->ss);
-		kfree(fs->scan.free_usages);
-		lafs_segtrack_free(fs->segtrack);
-		kfree(fs);
-		return NULL;
-	}
+	if (!fs->ss || !fs->scan.free_usages || err)
+		goto abort;
+
 	fs->checkpointcluster = le64_to_cpu(st->checkpointcluster);
 	for (i = 0; i < fs->maxsnapshot; i++) {
 		fs->ss[i].root_addr =
@@ -562,12 +558,18 @@ lafs_load(struct options *op, int newest)
 				   */
 
 	fs->devs = kzalloc(sizeof(struct fs_dev)*fs->devices, GFP_KERNEL);
-	if (!fs->devs) {
-		/* FIXME free more stuff */
-		kfree(fs->ss);
-		kfree(fs);
-		return NULL;
-	}
+	if (!fs->devs)
+		goto abort;
+
+	fs->prime_sb = sget(&lafs_fs_type, NULL, set_anon_super, NULL);
+	if (!fs->prime_sb)
+		goto abort;
+	fs->prime_sb->s_fs_info = fs;
+	fs->prime_sb->s_blocksize = 1 << op->blockbits;
+	fs->prime_sb->s_blocksize_bits = op->blockbits;
+	fs->prime_sb->s_op = &lafs_sops;
+	fs->prime_sb->s_export_op = &lafs_export_ops;
+	fs->prime_sb->s_root = NULL;
 
 	for (i = 0; i < fs->devices; i++) {
 		struct fs_dev *dv = &fs->devs[i];
@@ -578,10 +580,7 @@ lafs_load(struct options *op, int newest)
 		dv->sb->s_fs_info = fs;
 		dv->sb->s_blocksize = 1 << op->blockbits;
 		dv->sb->s_blocksize_bits = op->blockbits;
-		if (fs->prime_sb == NULL)
-			fs->prime_sb = dv->sb;
-		else
-			up_write(&dv->sb->s_umount);
+		up_write(&dv->sb->s_umount);
 
 		dv->devblk = de->devblock;
 		de->devblock = NULL;
@@ -629,6 +628,14 @@ lafs_load(struct options *op, int newest)
 		dv->sb->s_root = NULL;
 	}
 	return fs;
+
+abort:
+	kfree(fs->scan.free_usages);
+	lafs_segtrack_free(fs->segtrack);
+	kfree(fs->devs);
+	kfree(fs->ss);
+	kfree(fs);
+	return NULL;
 }
 
 static int show_orphans(struct fs *fs)
@@ -646,9 +653,9 @@ static int show_orphans(struct fs *fs)
 	return 1; /* meaningless, but makes it easy to add to wait_event below */
 }
 
-static void
-lafs_release(struct fs *fs)
+static void lafs_kill_sb(struct super_block *sb)
 {
+	struct fs *fs = sb->s_fs_info;
 	/* Release the 'struct fs' */
 	int i;
 
@@ -673,6 +680,8 @@ lafs_release(struct fs *fs)
 		   fs->scan.done == 1 &&
 		   fs->cleaner.active == 0);
 
+	kill_anon_super(fs->prime_sb);
+
 	for (i = 0; i < fs->devices; i++) {
 		struct fs_dev *dv = &fs->devs[i];
 		kfree(dv->devblk);
@@ -867,7 +876,11 @@ lafs_get_sb(struct file_system_type *fs_type,
 	if (err == 0)
 		err = lafs_start_cleaner(fs);
 	if (err)
-		lafs_release(fs);
+		deactivate_locked_super(fs->prime_sb);
+	else {
+		fs->prime_sb->s_flags |= MS_ACTIVE;
+		simple_set_mnt(mnt, fs->prime_sb);
+	}
 	/* And there you have it.  Filesystem all mounted, root dir found,
 	 * metadata files initialised, all pigs fed, and ready to fly!!!
 	 */
@@ -888,19 +901,7 @@ out:
 		}
 		kfree(op.devlist);
 	}
-	if (err)
-		return err;
-	else {
-		simple_set_mnt(mnt, fs->prime_sb);
-		return 0;
-	}
-}
-
-static void lafs_kill_sb(struct super_block *sb)
-{
-	struct fs *fs = sb->s_fs_info;
-
-	lafs_release(fs);
+	return err;
 }
 
 struct file_system_type lafs_fs_type = {