2014-07-12 11:14:48

by Chao Yu

[permalink] [raw]
Subject: [f2fs-dev][PATCH] f2fs: support ->rename2()

Now new interface ->rename2() is added to VFS, here are related description:
https://lkml.org/lkml/2014/2/7/873
https://lkml.org/lkml/2014/2/7/758

This patch adds function f2fs_rename2() to support ->rename2() including
handling both RENAME_EXCHANGE and RENAME_NOREPLACE flag.

Signed-off-by: Chao Yu <[email protected]>
---
fs/f2fs/namei.c | 164 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 164 insertions(+)

diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index 1b3cae0..27b0377 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -485,6 +485,169 @@ out:
return err;
}

+static int f2fs_cross_rename(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry)
+{
+ struct super_block *sb = old_dir->i_sb;
+ struct f2fs_sb_info *sbi = F2FS_SB(sb);
+ struct inode *old_inode = old_dentry->d_inode;
+ struct inode *new_inode = new_dentry->d_inode;
+ struct page *old_dir_page, *new_dir_page;
+ struct page *old_page, *new_page;
+ struct f2fs_dir_entry *old_dir_entry = NULL, *new_dir_entry = NULL;
+ struct f2fs_dir_entry *old_entry, *new_entry;
+ int old_nlink = 0, new_nlink = 0;
+ int err = -ENOENT;
+
+ f2fs_balance_fs(sbi);
+
+ old_entry = f2fs_find_entry(old_dir, &old_dentry->d_name, &old_page);
+ if (!old_entry)
+ goto out;
+
+ new_entry = f2fs_find_entry(new_dir, &new_dentry->d_name, &new_page);
+ if (!new_entry)
+ goto out_old;
+
+ /* prepare for updating ".." directory entry info later */
+ if (old_dir != new_dir) {
+ if (S_ISDIR(old_inode->i_mode)) {
+ err = -EIO;
+ old_dir_entry = f2fs_parent_dir(old_inode,
+ &old_dir_page);
+ if (!old_dir_entry)
+ goto out_new;
+ }
+
+ if (S_ISDIR(new_inode->i_mode)) {
+ err = -EIO;
+ new_dir_entry = f2fs_parent_dir(new_inode,
+ &new_dir_page);
+ if (!new_dir_entry)
+ goto out_old_dir;
+ }
+ }
+
+ /*
+ * If cross rename between file and directory those are not
+ * in the same directory, we will inc nlink of file's parent
+ * later, so we should check upper boundary of its nlink.
+ */
+ if ((!old_dir_entry || !new_dir_entry) &&
+ old_dir_entry != new_dir_entry) {
+ old_nlink = old_dir_entry ? -1 : 1;
+ new_nlink = -old_nlink;
+ err = -EMLINK;
+ if ((old_nlink > 0 && old_inode->i_nlink >= F2FS_LINK_MAX) ||
+ (new_nlink > 0 && new_inode->i_nlink >= F2FS_LINK_MAX))
+ goto out_new_dir;
+ }
+
+ f2fs_lock_op(sbi);
+
+ err = update_dent_inode(old_inode, &new_dentry->d_name);
+ if (err)
+ goto out_unlock;
+
+ err = update_dent_inode(new_inode, &old_dentry->d_name);
+ if (err)
+ goto out_undo;
+
+ /* update ".." directory entry info of old dentry */
+ if (old_dir_entry)
+ f2fs_set_link(old_inode, old_dir_entry, old_dir_page, new_dir);
+
+ /* update ".." directory entry info of new dentry */
+ if (new_dir_entry)
+ f2fs_set_link(new_inode, new_dir_entry, new_dir_page, old_dir);
+
+ /* update directory entry info of old dir inode */
+ f2fs_set_link(old_dir, old_entry, old_page, new_inode);
+
+ down_write(&F2FS_I(old_inode)->i_sem);
+ file_lost_pino(old_inode);
+ up_write(&F2FS_I(old_inode)->i_sem);
+
+ update_inode_page(old_inode);
+
+ old_dir->i_ctime = CURRENT_TIME;
+ if (old_nlink) {
+ down_write(&F2FS_I(old_dir)->i_sem);
+ if (old_nlink < 0)
+ drop_nlink(old_dir);
+ else
+ inc_nlink(old_dir);
+ up_write(&F2FS_I(old_dir)->i_sem);
+ }
+ mark_inode_dirty(old_dir);
+ update_inode_page(old_dir);
+
+ /* update directory entry info of new dir inode */
+ f2fs_set_link(new_dir, new_entry, new_page, old_inode);
+
+ down_write(&F2FS_I(new_inode)->i_sem);
+ file_lost_pino(new_inode);
+ up_write(&F2FS_I(new_inode)->i_sem);
+
+ update_inode_page(new_inode);
+
+ new_dir->i_ctime = CURRENT_TIME;
+ if (new_nlink) {
+ down_write(&F2FS_I(new_dir)->i_sem);
+ if (new_nlink < 0)
+ drop_nlink(new_dir);
+ else
+ inc_nlink(new_dir);
+ up_write(&F2FS_I(new_dir)->i_sem);
+ }
+ mark_inode_dirty(new_dir);
+ update_inode_page(new_dir);
+
+ f2fs_unlock_op(sbi);
+ return 0;
+out_undo:
+ /* Still we may fail to recover name info of f2fs_inode here */
+ update_dent_inode(old_inode, &old_dentry->d_name);
+out_unlock:
+ f2fs_unlock_op(sbi);
+out_new_dir:
+ if (new_dir_entry) {
+ kunmap(new_dir_page);
+ f2fs_put_page(new_dir_page, 0);
+ }
+out_old_dir:
+ if (old_dir_entry) {
+ kunmap(old_dir_page);
+ f2fs_put_page(old_dir_page, 0);
+ }
+out_new:
+ kunmap(new_page);
+ f2fs_put_page(new_page, 0);
+out_old:
+ kunmap(old_page);
+ f2fs_put_page(old_page, 0);
+out:
+ return err;
+}
+
+static int f2fs_rename2(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry,
+ unsigned int flags)
+{
+ if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE))
+ return -EINVAL;
+
+ if (flags & RENAME_EXCHANGE) {
+ return f2fs_cross_rename(old_dir, old_dentry,
+ new_dir, new_dentry);
+ }
+ /*
+ * VFS has already handled the new dentry existence case,
+ * here, we just deal with "RENAME_NOREPLACE" as regular rename.
+ */
+ return f2fs_rename(old_dir, old_dentry, new_dir, new_dentry);
+}
+
static int f2fs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode)
{
struct f2fs_sb_info *sbi = F2FS_SB(dir->i_sb);
@@ -542,6 +705,7 @@ const struct inode_operations f2fs_dir_inode_operations = {
.rmdir = f2fs_rmdir,
.mknod = f2fs_mknod,
.rename = f2fs_rename,
+ .rename2 = f2fs_rename2,
.tmpfile = f2fs_tmpfile,
.getattr = f2fs_getattr,
.setattr = f2fs_setattr,
--
2.0.1.474.g72c7794