diff options
| -rw-r--r-- | fs/ext2/dir.c | 44 | ||||
| -rw-r--r-- | include/linux/ext2_fs.h | 1 |
2 files changed, 33 insertions, 12 deletions
diff --git a/fs/ext2/dir.c b/fs/ext2/dir.c index 05d9342..d868e26 100644 --- a/fs/ext2/dir.c +++ b/fs/ext2/dir.c @@ -28,6 +28,24 @@ typedef struct ext2_dir_entry_2 ext2_dirent; +static inline unsigned ext2_rec_len_from_disk(__le16 dlen) +{ + unsigned len = le16_to_cpu(dlen); + + if (len == EXT2_MAX_REC_LEN) + return 1 << 16; + return len; +} + +static inline __le16 ext2_rec_len_to_disk(unsigned len) +{ + if (len == (1 << 16)) + return cpu_to_le16(EXT2_MAX_REC_LEN); + else if (len > (1 << 16)) + BUG(); + return cpu_to_le16(len); +} + /* * ext2 uses block-sized chunks. Arguably, sector-sized ones would be * more robust, but we have what we have @@ -106,7 +124,7 @@ static void ext2_check_page(struct page *page) } for (offs = 0; offs <= limit - EXT2_DIR_REC_LEN(1); offs += rec_len) { p = (ext2_dirent *)(kaddr + offs); - rec_len = le16_to_cpu(p->rec_len); + rec_len = ext2_rec_len_from_disk(p->rec_len); if (rec_len < EXT2_DIR_REC_LEN(1)) goto Eshort; @@ -204,7 +222,8 @@ static inline int ext2_match (int len, const char * const name, */ static inline ext2_dirent *ext2_next_entry(ext2_dirent *p) { - return (ext2_dirent *)((char*)p + le16_to_cpu(p->rec_len)); + return (ext2_dirent *)((char *)p + + ext2_rec_len_from_disk(p->rec_len)); } static inline unsigned @@ -316,7 +335,7 @@ ext2_readdir (struct file * filp, void * dirent, filldir_t filldir) return 0; } } - filp->f_pos += le16_to_cpu(de->rec_len); + filp->f_pos += ext2_rec_len_from_disk(de->rec_len); } ext2_put_page(page); } @@ -425,7 +444,7 @@ void ext2_set_link(struct inode *dir, struct ext2_dir_entry_2 *de, { loff_t pos = page_offset(page) + (char *) de - (char *) page_address(page); - unsigned len = le16_to_cpu(de->rec_len); + unsigned len = ext2_rec_len_from_disk(de->rec_len); int err; lock_page(page); @@ -482,7 +501,7 @@ int ext2_add_link (struct dentry *dentry, struct inode *inode) /* We hit i_size */ name_len = 0; rec_len = chunk_size; - de->rec_len = cpu_to_le16(chunk_size); + de->rec_len = ext2_rec_len_to_disk(chunk_size); de->inode = 0; goto got_it; } @@ -496,7 +515,7 @@ int ext2_add_link (struct dentry *dentry, struct inode *inode) if (ext2_match (namelen, name, de)) goto out_unlock; name_len = EXT2_DIR_REC_LEN(de->name_len); - rec_len = le16_to_cpu(de->rec_len); + rec_len = ext2_rec_len_from_disk(de->rec_len); if (!de->inode && rec_len >= reclen) goto got_it; if (rec_len >= name_len + reclen) @@ -518,8 +537,8 @@ got_it: goto out_unlock; if (de->inode) { ext2_dirent *de1 = (ext2_dirent *) ((char *) de + name_len); - de1->rec_len = cpu_to_le16(rec_len - name_len); - de->rec_len = cpu_to_le16(name_len); + de1->rec_len = ext2_rec_len_to_disk(rec_len - name_len); + de->rec_len = ext2_rec_len_to_disk(name_len); de = de1; } de->name_len = namelen; @@ -550,7 +569,8 @@ int ext2_delete_entry (struct ext2_dir_entry_2 * dir, struct page * page ) struct inode *inode = mapping->host; char *kaddr = page_address(page); unsigned from = ((char*)dir - kaddr) & ~(ext2_chunk_size(inode)-1); - unsigned to = ((char*)dir - kaddr) + le16_to_cpu(dir->rec_len); + unsigned to = ((char *)dir - kaddr) + + ext2_rec_len_from_disk(dir->rec_len); loff_t pos; ext2_dirent * pde = NULL; ext2_dirent * de = (ext2_dirent *) (kaddr + from); @@ -574,7 +594,7 @@ int ext2_delete_entry (struct ext2_dir_entry_2 * dir, struct page * page ) &page, NULL); BUG_ON(err); if (pde) - pde->rec_len = cpu_to_le16(to - from); + pde->rec_len = ext2_rec_len_to_disk(to - from); dir->inode = 0; err = ext2_commit_chunk(page, pos, to - from); inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC; @@ -610,14 +630,14 @@ int ext2_make_empty(struct inode *inode, struct inode *parent) memset(kaddr, 0, chunk_size); de = (struct ext2_dir_entry_2 *)kaddr; de->name_len = 1; - de->rec_len = cpu_to_le16(EXT2_DIR_REC_LEN(1)); + de->rec_len = ext2_rec_len_to_disk(EXT2_DIR_REC_LEN(1)); memcpy (de->name, ".\0\0", 4); de->inode = cpu_to_le32(inode->i_ino); ext2_set_de_type (de, inode); de = (struct ext2_dir_entry_2 *)(kaddr + EXT2_DIR_REC_LEN(1)); de->name_len = 2; - de->rec_len = cpu_to_le16(chunk_size - EXT2_DIR_REC_LEN(1)); + de->rec_len = ext2_rec_len_to_disk(chunk_size - EXT2_DIR_REC_LEN(1)); de->inode = cpu_to_le32(parent->i_ino); memcpy (de->name, "..\0", 4); ext2_set_de_type (de, inode); diff --git a/include/linux/ext2_fs.h b/include/linux/ext2_fs.h index c77c3bb..0f6c86c 100644 --- a/include/linux/ext2_fs.h +++ b/include/linux/ext2_fs.h @@ -561,6 +561,7 @@ enum { #define EXT2_DIR_ROUND (EXT2_DIR_PAD - 1) #define EXT2_DIR_REC_LEN(name_len) (((name_len) + 8 + EXT2_DIR_ROUND) & \ ~EXT2_DIR_ROUND) +#define EXT2_MAX_REC_LEN ((1<<16)-1) static inline ext2_fsblk_t ext2_group_first_block_no(struct super_block *sb, unsigned long group_no) |