1 files changed, 85 insertions, 45 deletions

diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 04824958cba5..a5ba1a858094 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -165,7 +165,7 @@ static int dx_make_map(struct ext4_dir_entry_2 *de, unsigned blocksize,
                        struct dx_hash_info *hinfo, struct dx_map_entry map[]);
 static void dx_sort_map(struct dx_map_entry *map, unsigned count);
 static struct ext4_dir_entry_2 *dx_move_dirents(char *from, char *to,
-                struct dx_map_entry *offsets, int count);
+                struct dx_map_entry *offsets, int count, unsigned blocksize);
 static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize);
 static void dx_insert_block(struct dx_frame *frame,
                                         u32 hash, ext4_lblk_t block);
@@ -180,14 +180,38 @@ static struct buffer_head * ext4_dx_find_entry(struct inode *dir,
 static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
                              struct inode *inode);
 
+unsigned int ext4_rec_len_from_disk(__le16 dlen, unsigned blocksize)
+{
+        unsigned len = le16_to_cpu(dlen);
+
+        if (len == EXT4_MAX_REC_LEN || len == 0)
+                return blocksize;
+        return (len & 65532) | ((len & 3) << 16);
+}
+  
+__le16 ext4_rec_len_to_disk(unsigned len, unsigned blocksize)
+{
+        if ((len > blocksize) || (blocksize > (1 << 18)) || (len & 3))
+                BUG();
+        if (len < 65536)
+                return cpu_to_le16(len);
+        if (len == blocksize) {
+                if (blocksize == 65536)
+                        return cpu_to_le16(EXT4_MAX_REC_LEN);
+                else 
+                        return cpu_to_le16(0);
+        }
+        return cpu_to_le16((len & 65532) | ((len >> 16) & 3));
+}
+
 /*
  * p is at least 6 bytes before the end of page
  */
 static inline struct ext4_dir_entry_2 *
-ext4_next_entry(struct ext4_dir_entry_2 *p)
+ext4_next_entry(struct ext4_dir_entry_2 *p, unsigned long blocksize)
 {
         return (struct ext4_dir_entry_2 *)((char *)p +
-                ext4_rec_len_from_disk(p->rec_len));
+                ext4_rec_len_from_disk(p->rec_len, blocksize));
 }
 
 /*
@@ -294,7 +318,7 @@ static struct stats dx_show_leaf(struct dx_hash_info *hinfo, struct ext4_dir_ent
                         space += EXT4_DIR_REC_LEN(de->name_len);
                         names++;
                 }
-                de = ext4_next_entry(de);
+                de = ext4_next_entry(de, size);
         }
         printk("(%i)\n", names);
         return (struct stats) { names, space, 1 };
@@ -585,7 +609,7 @@ static int htree_dirblock_to_tree(struct file *dir_file,
         top = (struct ext4_dir_entry_2 *) ((char *) de +
                                            dir->i_sb->s_blocksize -
                                            EXT4_DIR_REC_LEN(0));
-        for (; de < top; de = ext4_next_entry(de)) {
+        for (; de < top; de = ext4_next_entry(de, dir->i_sb->s_blocksize)) {
                 if (!ext4_check_dir_entry("htree_dirblock_to_tree", dir, de, bh,
                                         (block<<EXT4_BLOCK_SIZE_BITS(dir->i_sb))
                                                 +((char *)de - bh->b_data))) {
@@ -663,7 +687,7 @@ int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
         }
         if (start_hash < 2 || (start_hash ==2 && start_minor_hash==0)) {
                 de = (struct ext4_dir_entry_2 *) frames[0].bh->b_data;
-                de = ext4_next_entry(de);
+                de = ext4_next_entry(de, dir->i_sb->s_blocksize);
                 if ((err = ext4_htree_store_dirent(dir_file, 2, 0, de)) != 0)
                         goto errout;
                 count++;
@@ -732,7 +756,7 @@ static int dx_make_map(struct ext4_dir_entry_2 *de, unsigned blocksize,
                         cond_resched();
                 }
                 /* XXX: do we need to check rec_len == 0 case? -Chris */
-                de = ext4_next_entry(de);
+                de = ext4_next_entry(de, blocksize);
         }
         return count;
 }
@@ -832,7 +856,8 @@ static inline int search_dirblock(struct buffer_head *bh,
                         return 1;
                 }
                 /* prevent looping on a bad block */
-                de_len = ext4_rec_len_from_disk(de->rec_len);
+                de_len = ext4_rec_len_from_disk(de->rec_len,
+                                                dir->i_sb->s_blocksize);
                 if (de_len <= 0)
                         return -1;
                 offset += de_len;
@@ -996,7 +1021,7 @@ static struct buffer_head * ext4_dx_find_entry(struct inode *dir, const struct q
                 de = (struct ext4_dir_entry_2 *) bh->b_data;
                 top = (struct ext4_dir_entry_2 *) ((char *) de + sb->s_blocksize -
                                        EXT4_DIR_REC_LEN(0));
-                for (; de < top; de = ext4_next_entry(de)) {
+                for (; de < top; de = ext4_next_entry(de, sb->s_blocksize)) {
                         int off = (block << EXT4_BLOCK_SIZE_BITS(sb))
                                   + ((char *) de - bh->b_data);
 
@@ -1109,7 +1134,8 @@ static inline void ext4_set_de_type(struct super_block *sb,
  * Returns pointer to last entry moved.
  */
 static struct ext4_dir_entry_2 *
-dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count)
+dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count,
+                unsigned blocksize)
 {
         unsigned rec_len = 0;
 
@@ -1118,7 +1144,7 @@ dx_move_dirents(char *from, char *to, struct dx_map_entry *map, int count)
                 rec_len = EXT4_DIR_REC_LEN(de->name_len);
                 memcpy (to, de, rec_len);
                 ((struct ext4_dir_entry_2 *) to)->rec_len =
-                                ext4_rec_len_to_disk(rec_len);
+                                ext4_rec_len_to_disk(rec_len, blocksize);
                 de->inode = 0;
                 map++;
                 to += rec_len;
@@ -1137,12 +1163,12 @@ static struct ext4_dir_entry_2* dx_pack_dirents(char *base, unsigned blocksize)
 
         prev = to = de;
         while ((char*)de < base + blocksize) {
-                next = ext4_next_entry(de);
+                next = ext4_next_entry(de, blocksize);
                 if (de->inode && de->name_len) {
                         rec_len = EXT4_DIR_REC_LEN(de->name_len);
                         if (de > to)
                                 memmove(to, de, rec_len);
-                        to->rec_len = ext4_rec_len_to_disk(rec_len);
+                        to->rec_len = ext4_rec_len_to_disk(rec_len, blocksize);
                         prev = to;
                         to = (struct ext4_dir_entry_2 *) (((char *) to) + rec_len);
                 }
@@ -1215,10 +1241,12 @@ static struct ext4_dir_entry_2 *do_split(handle_t *handle, struct inode *dir,
                                         hash2, split, count-split));
 
         /* Fancy dance to stay within two buffers */
-        de2 = dx_move_dirents(data1, data2, map + split, count - split);
+        de2 = dx_move_dirents(data1, data2, map + split, count - split, blocksize);
         de = dx_pack_dirents(data1, blocksize);
-        de->rec_len = ext4_rec_len_to_disk(data1 + blocksize - (char *) de);
-        de2->rec_len = ext4_rec_len_to_disk(data2 + blocksize - (char *) de2);
+        de->rec_len = ext4_rec_len_to_disk(data1 + blocksize - (char *) de,
+                                           blocksize);
+        de2->rec_len = ext4_rec_len_to_disk(data2 + blocksize - (char *) de2,
+                                            blocksize);
         dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data1, blocksize, 1));
         dxtrace(dx_show_leaf (hinfo, (struct ext4_dir_entry_2 *) data2, blocksize, 1));
 
@@ -1268,6 +1296,7 @@ static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
         const char      *name = dentry->d_name.name;
         int             namelen = dentry->d_name.len;
         unsigned int    offset = 0;
+        unsigned int    blocksize = dir->i_sb->s_blocksize;
         unsigned short  reclen;
         int             nlen, rlen, err;
         char            *top;
@@ -1275,7 +1304,7 @@ static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
         reclen = EXT4_DIR_REC_LEN(namelen);
         if (!de) {
                 de = (struct ext4_dir_entry_2 *)bh->b_data;
-                top = bh->b_data + dir->i_sb->s_blocksize - reclen;
+                top = bh->b_data + blocksize - reclen;
                 while ((char *) de <= top) {
                         if (!ext4_check_dir_entry("ext4_add_entry", dir, de,
                                                   bh, offset)) {
@@ -1287,7 +1316,7 @@ static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
                                 return -EEXIST;
                         }
                         nlen = EXT4_DIR_REC_LEN(de->name_len);
-                        rlen = ext4_rec_len_from_disk(de->rec_len);
+                        rlen = ext4_rec_len_from_disk(de->rec_len, blocksize);
                         if ((de->inode? rlen - nlen: rlen) >= reclen)
                                 break;
                         de = (struct ext4_dir_entry_2 *)((char *)de + rlen);
@@ -1306,11 +1335,11 @@ static int add_dirent_to_buf(handle_t *handle, struct dentry *dentry,
 
         /* By now the buffer is marked for journaling */
         nlen = EXT4_DIR_REC_LEN(de->name_len);
-        rlen = ext4_rec_len_from_disk(de->rec_len);
+        rlen = ext4_rec_len_from_disk(de->rec_len, blocksize);
         if (de->inode) {
                 struct ext4_dir_entry_2 *de1 = (struct ext4_dir_entry_2 *)((char *)de + nlen);
-                de1->rec_len = ext4_rec_len_to_disk(rlen - nlen);
-                de->rec_len = ext4_rec_len_to_disk(nlen);
+                de1->rec_len = ext4_rec_len_to_disk(rlen - nlen, blocksize);
+                de->rec_len = ext4_rec_len_to_disk(nlen, blocksize);
                 de = de1;
         }
         de->file_type = EXT4_FT_UNKNOWN;
@@ -1380,7 +1409,7 @@ static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
         /* The 0th block becomes the root, move the dirents out */
         fde = &root->dotdot;
         de = (struct ext4_dir_entry_2 *)((char *)fde +
-                ext4_rec_len_from_disk(fde->rec_len));
+                ext4_rec_len_from_disk(fde->rec_len, blocksize));
         if ((char *) de >= (((char *) root) + blocksize)) {
                 ext4_error(dir->i_sb, __func__,
                            "invalid rec_len for '..' in inode %lu",
@@ -1402,12 +1431,14 @@ static int make_indexed_dir(handle_t *handle, struct dentry *dentry,
         memcpy (data1, de, len);
         de = (struct ext4_dir_entry_2 *) data1;
         top = data1 + len;
-        while ((char *)(de2 = ext4_next_entry(de)) < top)
+        while ((char *)(de2 = ext4_next_entry(de, blocksize)) < top)
                 de = de2;
-        de->rec_len = ext4_rec_len_to_disk(data1 + blocksize - (char *) de);
+        de->rec_len = ext4_rec_len_to_disk(data1 + blocksize - (char *) de,
+                                           blocksize);
         /* Initialize the root; the dot dirents already exist */
         de = (struct ext4_dir_entry_2 *) (&root->dotdot);
-        de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2));
+        de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(2),
+                                           blocksize);
         memset (&root->info, 0, sizeof(root->info));
         root->info.info_length = sizeof(root->info);
         root->info.hash_version = EXT4_SB(dir->i_sb)->s_def_hash_version;
@@ -1488,7 +1519,7 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
                 return retval;
         de = (struct ext4_dir_entry_2 *) bh->b_data;
         de->inode = 0;
-        de->rec_len = ext4_rec_len_to_disk(blocksize);
+        de->rec_len = ext4_rec_len_to_disk(blocksize, blocksize);
         return add_dirent_to_buf(handle, dentry, inode, de, bh);
 }
 
@@ -1551,7 +1582,8 @@ static int ext4_dx_add_entry(handle_t *handle, struct dentry *dentry,
                         goto cleanup;
                 node2 = (struct dx_node *)(bh2->b_data);
                 entries2 = node2->entries;
-                node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize);
+                node2->fake.rec_len = ext4_rec_len_to_disk(sb->s_blocksize,
+                                                           sb->s_blocksize);
                 node2->fake.inode = 0;
                 BUFFER_TRACE(frame->bh, "get_write_access");
                 err = ext4_journal_get_write_access(handle, frame->bh);
@@ -1639,6 +1671,7 @@ static int ext4_delete_entry(handle_t *handle,
                              struct buffer_head *bh)
 {
         struct ext4_dir_entry_2 *de, *pde;
+        unsigned int blocksize = dir->i_sb->s_blocksize;
         int i;
 
         i = 0;
@@ -1652,8 +1685,11 @@ static int ext4_delete_entry(handle_t *handle,
                         ext4_journal_get_write_access(handle, bh);
                         if (pde)
                                 pde->rec_len = ext4_rec_len_to_disk(
-                                        ext4_rec_len_from_disk(pde->rec_len) +
-                                        ext4_rec_len_from_disk(de->rec_len));
+                                        ext4_rec_len_from_disk(pde->rec_len,
+                                                               blocksize) +
+                                        ext4_rec_len_from_disk(de->rec_len,
+                                                               blocksize),
+                                        blocksize);
                         else
                                 de->inode = 0;
                         dir->i_version++;
@@ -1661,9 +1697,9 @@ static int ext4_delete_entry(handle_t *handle,
                         ext4_handle_dirty_metadata(handle, dir, bh);
                         return 0;
                 }
-                i += ext4_rec_len_from_disk(de->rec_len);
+                i += ext4_rec_len_from_disk(de->rec_len, blocksize);
                 pde = de;
-                de = ext4_next_entry(de);
+                de = ext4_next_entry(de, blocksize);
         }
         return -ENOENT;
 }
@@ -1793,6 +1829,7 @@ static int ext4_mkdir(struct inode *dir, struct dentry *dentry, int mode)
         struct inode *inode;
         struct buffer_head *dir_block;
         struct ext4_dir_entry_2 *de;
+        unsigned int blocksize = dir->i_sb->s_blocksize;
         int err, retries = 0;
 
         if (EXT4_DIR_LINK_MAX(dir))
@@ -1824,13 +1861,14 @@ retry:
         de = (struct ext4_dir_entry_2 *) dir_block->b_data;
         de->inode = cpu_to_le32(inode->i_ino);
         de->name_len = 1;
-        de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len));
+        de->rec_len = ext4_rec_len_to_disk(EXT4_DIR_REC_LEN(de->name_len),
+                                           blocksize);
         strcpy(de->name, ".");
         ext4_set_de_type(dir->i_sb, de, S_IFDIR);
-        de = ext4_next_entry(de);
+        de = ext4_next_entry(de, blocksize);
         de->inode = cpu_to_le32(dir->i_ino);
-        de->rec_len = ext4_rec_len_to_disk(inode->i_sb->s_blocksize -
-                                                EXT4_DIR_REC_LEN(1));
+        de->rec_len = ext4_rec_len_to_disk(blocksize - EXT4_DIR_REC_LEN(1),
+                                           blocksize);
         de->name_len = 2;
         strcpy(de->name, "..");
         ext4_set_de_type(dir->i_sb, de, S_IFDIR);
@@ -1885,7 +1923,7 @@ static int empty_dir(struct inode *inode)
                 return 1;
         }
         de = (struct ext4_dir_entry_2 *) bh->b_data;
-        de1 = ext4_next_entry(de);
+        de1 = ext4_next_entry(de, sb->s_blocksize);
         if (le32_to_cpu(de->inode) != inode->i_ino ||
                         !le32_to_cpu(de1->inode) ||
                         strcmp(".", de->name) ||
@@ -1896,9 +1934,9 @@ static int empty_dir(struct inode *inode)
                 brelse(bh);
                 return 1;
         }
-        offset = ext4_rec_len_from_disk(de->rec_len) +
-                 ext4_rec_len_from_disk(de1->rec_len);
-        de = ext4_next_entry(de1);
+        offset = ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize) +
+                 ext4_rec_len_from_disk(de1->rec_len, sb->s_blocksize);
+        de = ext4_next_entry(de1, sb->s_blocksize);
         while (offset < inode->i_size) {
                 if (!bh ||
                         (void *) de >= (void *) (bh->b_data+sb->s_blocksize)) {
@@ -1927,8 +1965,8 @@ static int empty_dir(struct inode *inode)
                         brelse(bh);
                         return 0;
                 }
-                offset += ext4_rec_len_from_disk(de->rec_len);
-                de = ext4_next_entry(de);
+                offset += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize);
+                de = ext4_next_entry(de, sb->s_blocksize);
         }
         brelse(bh);
         return 1;
@@ -2297,8 +2335,8 @@ retry:
         return err;
 }
 
-#define PARENT_INO(buffer) \
-        (ext4_next_entry((struct ext4_dir_entry_2 *)(buffer))->inode)
+#define PARENT_INO(buffer, size) \
+        (ext4_next_entry((struct ext4_dir_entry_2 *)(buffer), size)->inode)
 
 /*
  * Anybody can rename anything with this: the permission checks are left to the
@@ -2358,7 +2396,8 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
                 dir_bh = ext4_bread(handle, old_inode, 0, 0, &retval);
                 if (!dir_bh)
                         goto end_rename;
-                if (le32_to_cpu(PARENT_INO(dir_bh->b_data)) != old_dir->i_ino)
+                if (le32_to_cpu(PARENT_INO(dir_bh->b_data,
+                                old_dir->i_sb->s_blocksize)) != old_dir->i_ino)
                         goto end_rename;
                 retval = -EMLINK;
                 if (!new_inode && new_dir != old_dir &&
@@ -2430,7 +2469,8 @@ static int ext4_rename(struct inode *old_dir, struct dentry *old_dentry,
         if (dir_bh) {
                 BUFFER_TRACE(dir_bh, "get_write_access");
                 ext4_journal_get_write_access(handle, dir_bh);
-                PARENT_INO(dir_bh->b_data) = cpu_to_le32(new_dir->i_ino);
+                PARENT_INO(dir_bh->b_data, new_dir->i_sb->s_blocksize) =
+                                                cpu_to_le32(new_dir->i_ino);
                 BUFFER_TRACE(dir_bh, "call ext4_handle_dirty_metadata");
                 ext4_handle_dirty_metadata(handle, old_dir, dir_bh);
                 ext4_dec_count(handle, old_dir);