qnx4: clean qnx4_fill_super() up

* pass on-disk superblock to qnx4_chkroot() explicitly
* don't leave stale (and unused) pointers in qnx4_super_block
* free stuff in ->kill_sb(); ->put_super() becomes empty and dies
* simplify failure exits

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

2 files changed, 22 insertions, 43 deletions

diff --git a/fs/qnx4/inode.c b/fs/qnx4/inode.c
index 2e8caa62da78..89558810381c 100644
--- a/fs/qnx4/inode.c
+++ b/fs/qnx4/inode.c
@@ -27,7 +27,6 @@
 
 static const struct super_operations qnx4_sops;
 
-static void qnx4_put_super(struct super_block *sb);
 static struct inode *qnx4_alloc_inode(struct super_block *sb);
 static void qnx4_destroy_inode(struct inode *inode);
 static int qnx4_remount(struct super_block *sb, int *flags, char *data);
@@ -37,7 +36,6 @@ static const struct super_operations qnx4_sops =
 {
         .alloc_inode    = qnx4_alloc_inode,
         .destroy_inode  = qnx4_destroy_inode,
-        .put_super      = qnx4_put_super,
         .statfs         = qnx4_statfs,
         .remount_fs     = qnx4_remount,
 };
@@ -148,18 +146,19 @@ static int qnx4_statfs(struct dentry *dentry, struct kstatfs *buf)
  * it really _is_ a qnx4 filesystem, and to check the size
  * of the directory entry.
  */
-static const char *qnx4_checkroot(struct super_block *sb)
+static const char *qnx4_checkroot(struct super_block *sb,
+                                  struct qnx4_super_block *s)
 {
         struct buffer_head *bh;
         struct qnx4_inode_entry *rootdir;
         int rd, rl;
         int i, j;
 
-        if (*(qnx4_sb(sb)->sb->RootDir.di_fname) != '/')
+        if (s->RootDir.di_fname[0] != '/' || s->RootDir.di_fname[1] != '\0')
                 return "no qnx4 filesystem (no root dir).";
         QNX4DEBUG((KERN_NOTICE "QNX4 filesystem found on dev %s.\n", sb->s_id));
-        rd = le32_to_cpu(qnx4_sb(sb)->sb->RootDir.di_first_xtnt.xtnt_blk) - 1;
-        rl = le32_to_cpu(qnx4_sb(sb)->sb->RootDir.di_first_xtnt.xtnt_size);
+        rd = le32_to_cpu(s->RootDir.di_first_xtnt.xtnt_blk) - 1;
+        rl = le32_to_cpu(s->RootDir.di_first_xtnt.xtnt_size);
         for (j = 0; j < rl; j++) {
                 bh = sb_bread(sb, rd + j);      /* root dir, first block */
                 if (bh == NULL)
@@ -189,7 +188,6 @@ static int qnx4_fill_super(struct super_block *s, void *data, int silent)
         struct inode *root;
         const char *errmsg;
         struct qnx4_sb_info *qs;
-        int ret = -EINVAL;
 
         qs = kzalloc(sizeof(struct qnx4_sb_info), GFP_KERNEL);
         if (!qs)
@@ -198,67 +196,50 @@ static int qnx4_fill_super(struct super_block *s, void *data, int silent)
 
         sb_set_blocksize(s, QNX4_BLOCK_SIZE);
 
+        s->s_op = &qnx4_sops;
+        s->s_magic = QNX4_SUPER_MAGIC;
+        s->s_flags |= MS_RDONLY;        /* Yup, read-only yet */
+
         /* Check the superblock signature. Since the qnx4 code is
            dangerous, we should leave as quickly as possible
            if we don't belong here... */
         bh = sb_bread(s, 1);
         if (!bh) {
                 printk(KERN_ERR "qnx4: unable to read the superblock\n");
-                goto outnobh;
+                return -EINVAL;
         }
-        if ( le32_to_cpup((__le32*) bh->b_data) != QNX4_SUPER_MAGIC ) {
-                if (!silent)
-                        printk(KERN_ERR "qnx4: wrong fsid in superblock.\n");
-                goto out;
-        }
-        s->s_op = &qnx4_sops;
-        s->s_magic = QNX4_SUPER_MAGIC;
-        s->s_flags |= MS_RDONLY;        /* Yup, read-only yet */
-        qnx4_sb(s)->sb_buf = bh;
-        qnx4_sb(s)->sb = (struct qnx4_super_block *) bh->b_data;
-
 
         /* check before allocating dentries, inodes, .. */
-        errmsg = qnx4_checkroot(s);
+        errmsg = qnx4_checkroot(s, (struct qnx4_super_block *) bh->b_data);
+        brelse(bh);
         if (errmsg != NULL) {
                 if (!silent)
                         printk(KERN_ERR "qnx4: %s\n", errmsg);
-                goto out;
+                return -EINVAL;
         }
 
         /* does root not have inode number QNX4_ROOT_INO ?? */
         root = qnx4_iget(s, QNX4_ROOT_INO * QNX4_INODES_PER_BLOCK);
         if (IS_ERR(root)) {
                 printk(KERN_ERR "qnx4: get inode failed\n");
-                ret = PTR_ERR(root);
-                goto outb;
+                return PTR_ERR(root);
         }
 
-        ret = -ENOMEM;
         s->s_root = d_make_root(root);
         if (s->s_root == NULL)
-                goto outb;
+                return -ENOMEM;
 
-        brelse(bh);
         return 0;
-
-      outb:
-        kfree(qs->BitMap);
-      out:
-        brelse(bh);
-      outnobh:
-        kfree(qs);
-        s->s_fs_info = NULL;
-        return ret;
 }
 
-static void qnx4_put_super(struct super_block *sb)
+static void qnx4_kill_sb(struct super_block *sb)
 {
         struct qnx4_sb_info *qs = qnx4_sb(sb);
-        kfree( qs->BitMap );
-        kfree( qs );
-        sb->s_fs_info = NULL;
-        return;
+        kill_block_super(sb);
+        if (qs) {
+                kfree(qs->BitMap);
+                kfree(qs);
+        }
 }
 
 static int qnx4_readpage(struct file *file, struct page *page)
@@ -409,7 +390,7 @@ static struct file_system_type qnx4_fs_type = {
         .owner          = THIS_MODULE,
         .name           = "qnx4",
         .mount          = qnx4_mount,
-        .kill_sb        = kill_block_super,
+        .kill_sb        = qnx4_kill_sb,
         .fs_flags       = FS_REQUIRES_DEV,
 };
 MODULE_ALIAS_FS("qnx4");
diff --git a/fs/qnx4/qnx4.h b/fs/qnx4/qnx4.h
index 34e2d329c97e..c9b1be2c164d 100644
--- a/fs/qnx4/qnx4.h
+++ b/fs/qnx4/qnx4.h
@@ -10,8 +10,6 @@
 #endif
 
 struct qnx4_sb_info {
-        struct buffer_head      *sb_buf;        /* superblock buffer */
-        struct qnx4_super_block *sb;            /* our superblock */
         unsigned int            Version;        /* may be useful */
         struct qnx4_inode_entry *BitMap;        /* useful */
 };