This adds a directory lookup function nilfs_find_entry_by_ino(), which finds a directory entry by an inode number instead of a file name.
Signed-off-by: Ryusuke Konishi <[email protected]> --- fs/nilfs2/dir.c | 60 +++++++++++++++++++++++++++++++++++++++++++++++++++++ fs/nilfs2/nilfs.h | 2 + 2 files changed, 62 insertions(+), 0 deletions(-) diff --git a/fs/nilfs2/dir.c b/fs/nilfs2/dir.c index 3a19239..bc0512b 100644 --- a/fs/nilfs2/dir.c +++ b/fs/nilfs2/dir.c @@ -395,6 +395,66 @@ found: return de; } +struct nilfs_dir_entry * +nilfs_find_entry_by_ino(struct inode *dir, ino_t ino, struct page **res_page) +{ + unsigned reclen = NILFS_DIR_REC_LEN(1); + unsigned long start, n; + unsigned long npages = dir_pages(dir); + struct page *page = NULL; + struct nilfs_inode_info *ii = NILFS_I(dir); + struct nilfs_dir_entry *de; + void *kaddr; + + if (npages == 0) + goto out; + + /* OFFSET_CACHE */ + *res_page = NULL; + + start = ii->i_dir_start_lookup; + if (start >= npages) + start = 0; + n = start; + do { + page = nilfs_get_page(dir, n); + if (!IS_ERR(page)) { + kaddr = page_address(page); + de = kaddr; + kaddr += nilfs_last_byte(dir, n) - reclen; + while ((void *)de <= kaddr) { + if (de->rec_len == 0) { + nilfs_error(dir->i_sb, __func__, + "zero-length directory entry"); + nilfs_put_page(page); + goto out; + } + if (le64_to_cpu(de->inode) == ino) + goto found; + de = nilfs_next_entry(de); + } + nilfs_put_page(page); + } + if (++n >= npages) + n = 0; + /* next page is past the blocks we've got */ + if (unlikely(n > (dir->i_blocks >> (PAGE_CACHE_SHIFT - 9)))) { + nilfs_error(dir->i_sb, __func__, + "dir %lu size %lld exceeds block count %llu", + dir->i_ino, dir->i_size, + (unsigned long long)dir->i_blocks); + goto out; + } + } while (n != start); +out: + return NULL; + +found: + *res_page = page; + ii->i_dir_start_lookup = n; + return de; +} + struct nilfs_dir_entry *nilfs_dotdot(struct inode *dir, struct page **p) { struct page *page = nilfs_get_page(dir, 0); diff --git a/fs/nilfs2/nilfs.h b/fs/nilfs2/nilfs.h index 40bada2..1e47669 100644 --- a/fs/nilfs2/nilfs.h +++ b/fs/nilfs2/nilfs.h @@ -229,6 +229,8 @@ extern ino_t nilfs_inode_by_name(struct inode *, const struct qstr *); extern int nilfs_make_empty(struct inode *, struct inode *); extern struct nilfs_dir_entry * nilfs_find_entry(struct inode *, const struct qstr *, struct page **); +struct nilfs_dir_entry * +nilfs_find_entry_by_ino(struct inode *dir, ino_t ino, struct page **res_page); extern int nilfs_delete_entry(struct nilfs_dir_entry *, struct page *); extern int nilfs_empty_dir(struct inode *); extern struct nilfs_dir_entry *nilfs_dotdot(struct inode *, struct page **); -- 1.7.3.5 -- To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
