ext4: convert dx_probe() to use the ERR_PTR convention

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

1 files changed, 35 insertions, 54 deletions

diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index af13c908f617..e6d51655ffcd 100644
--- 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);