ext4: convert dx_probe() to use the ERR_PTR convention

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index af13c90..e6d5165 100644 (file)
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -253,8 +253,7 @@ static unsigned dx_node_limit(struct inode *dir);
 static struct dx_frame *dx_probe(const struct qstr *d_name,
                                 struct inode *dir,
                                 struct dx_hash_info *hinfo,
-                                struct dx_frame *frame,
-                                int *err);
+                                struct dx_frame *frame);
 static void dx_release(struct dx_frame *frames);
 static int dx_make_map(struct ext4_dir_entry_2 *de, unsigned blocksize,
                       struct dx_hash_info *hinfo, struct dx_map_entry map[]);
@@ -670,29 +669,25 @@ struct stats dx_show_entries(struct dx_hash_info *hinfo, struct inode *dir,
  */
 static struct dx_frame *
 dx_probe(const struct qstr *d_name, struct inode *dir,
-        struct dx_hash_info *hinfo, struct dx_frame *frame_in, int *err)
+        struct dx_hash_info *hinfo, struct dx_frame *frame_in)
 {
        unsigned count, indirect;
        struct dx_entry *at, *entries, *p, *q, *m;
        struct dx_root *root;
-       struct buffer_head *bh;
        struct dx_frame *frame = frame_in;
+       struct dx_frame *ret_err = ERR_PTR(ERR_BAD_DX_DIR);
        u32 hash;
 
-       frame->bh = NULL;
-       bh = ext4_read_dirblock(dir, 0, INDEX);
-       if (IS_ERR(bh)) {
-               *err = PTR_ERR(bh);
-               goto fail;
-       }
-       root = (struct dx_root *) bh->b_data;
+       frame->bh = ext4_read_dirblock(dir, 0, INDEX);
+       if (IS_ERR(frame->bh))
+               return (struct dx_frame *) frame->bh;
+
+       root = (struct dx_root *) frame->bh->b_data;
        if (root->info.hash_version != DX_HASH_TEA &&
            root->info.hash_version != DX_HASH_HALF_MD4 &&
            root->info.hash_version != DX_HASH_LEGACY) {
                ext4_warning(dir->i_sb, "Unrecognised inode hash code %d",
                             root->info.hash_version);
-               brelse(bh);
-               *err = ERR_BAD_DX_DIR;
                goto fail;
        }
        hinfo->hash_version = root->info.hash_version;
@@ -706,16 +701,12 @@ dx_probe(const struct qstr *d_name, struct inode *dir,
        if (root->info.unused_flags & 1) {
                ext4_warning(dir->i_sb, "Unimplemented inode hash flags: %#06x",
                             root->info.unused_flags);
-               brelse(bh);
-               *err = ERR_BAD_DX_DIR;
                goto fail;
        }
 
        if ((indirect = root->info.indirect_levels) > 1) {
                ext4_warning(dir->i_sb, "Unimplemented inode hash depth: %#06x",
                             root->info.indirect_levels);
-               brelse(bh);
-               *err = ERR_BAD_DX_DIR;
                goto fail;
        }
 
@@ -725,27 +716,21 @@ dx_probe(const struct qstr *d_name, struct inode *dir,
        if (dx_get_limit(entries) != dx_root_limit(dir,
                                                   root->info.info_length)) {
                ext4_warning(dir->i_sb, "dx entry: limit != root limit");
-               brelse(bh);
-               *err = ERR_BAD_DX_DIR;
                goto fail;
        }
 
        dxtrace(printk("Look up %x", hash));
-       while (1)
-       {
+       while (1) {
                count = dx_get_count(entries);
                if (!count || count > dx_get_limit(entries)) {
                        ext4_warning(dir->i_sb,
                                     "dx entry: no count or count > limit");
-                       brelse(bh);
-                       *err = ERR_BAD_DX_DIR;
-                       goto fail2;
+                       goto fail;
                }
 
                p = entries + 1;
                q = entries + count - 1;
-               while (p <= q)
-               {
+               while (p <= q) {
                        m = p + (q - p)/2;
                        dxtrace(printk("."));
                        if (dx_get_hash(m) > hash)
@@ -754,8 +739,7 @@ dx_probe(const struct qstr *d_name, struct inode *dir,
                                p = m + 1;
                }
 
-               if (0) // linear search cross check
-               {
+               if (0) { // linear search cross check
                        unsigned n = count - 1;
                        at = entries;
                        while (n--)
@@ -772,38 +756,35 @@ dx_probe(const struct qstr *d_name, struct inode *dir,
 
                at = p - 1;
                dxtrace(printk(" %x->%u\n", at == entries? 0: dx_get_hash(at), dx_get_block(at)));
-               frame->bh = bh;
                frame->entries = entries;
                frame->at = at;
-               if (!indirect--) return frame;
-               bh = ext4_read_dirblock(dir, dx_get_block(at), INDEX);
-               if (IS_ERR(bh)) {
-                       *err = PTR_ERR(bh);
-                       goto fail2;
+               if (!indirect--)
+                       return frame;
+               frame++;
+               frame->bh = ext4_read_dirblock(dir, dx_get_block(at), INDEX);
+               if (IS_ERR(frame->bh)) {
+                       ret_err = (struct dx_frame *) frame->bh;
+                       frame->bh = NULL;
+                       goto fail;
                }
-               entries = ((struct dx_node *) bh->b_data)->entries;
+               entries = ((struct dx_node *) frame->bh->b_data)->entries;
 
                if (dx_get_limit(entries) != dx_node_limit (dir)) {
                        ext4_warning(dir->i_sb,
                                     "dx entry: limit != node limit");
-                       brelse(bh);
-                       *err = ERR_BAD_DX_DIR;
-                       goto fail2;
+                       goto fail;
                }
-               frame++;
-               frame->bh = NULL;
        }
-fail2:
+fail:
        while (frame >= frame_in) {
                brelse(frame->bh);
                frame--;
        }
-fail:
-       if (*err == ERR_BAD_DX_DIR)
+       if (ret_err == ERR_PTR(ERR_BAD_DX_DIR))
                ext4_warning(dir->i_sb,
                             "Corrupt dir inode %lu, running e2fsck is "
                             "recommended.", dir->i_ino);
-       return NULL;
+       return ret_err;
 }
 
 static void dx_release (struct dx_frame *frames)
@@ -989,9 +970,9 @@ int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
        }
        hinfo.hash = start_hash;
        hinfo.minor_hash = 0;
-       frame = dx_probe(NULL, dir, &hinfo, frames, &err);
-       if (!frame)
-               return err;
+       frame = dx_probe(NULL, dir, &hinfo, frames);
+       if (IS_ERR(frame))
+               return PTR_ERR(frame);
 
        /* Add '.' and '..' from the htree header */
        if (!start_hash && !start_minor_hash) {
@@ -1369,11 +1350,11 @@ static struct buffer_head * ext4_dx_find_entry(struct inode *dir, const struct q
        struct dx_frame frames[2], *frame;
        struct buffer_head *bh;
        ext4_lblk_t block;
-       int err = 0, retval;
+       int retval;
 
-       frame = dx_probe(d_name, dir, &hinfo, frames, &err);
-       if (err)
-               return ERR_PTR(err);
+       frame = dx_probe(d_name, dir, &hinfo, frames);
+       if (IS_ERR(frame))
+               return (struct buffer_head *) frame;
        do {
                block = dx_get_block(frame->at);
                bh = ext4_read_dirblock(dir, block, DIRENT);
@@ -1977,9 +1958,9 @@ static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
        struct ext4_dir_entry_2 *de;
        int err;
 
-       frame = dx_probe(&dentry->d_name, dir, &hinfo, frames, &err);
-       if (!frame)
-               return err;
+       frame = dx_probe(&dentry->d_name, dir, &hinfo, frames);
+       if (IS_ERR(frame))
+               return PTR_ERR(frame);
        entries = frame->entries;
        at = frame->at;
        bh = ext4_read_dirblock(dir, dx_get_block(frame->at), DIRENT);