From af7bd4dc13093bf1477f370722bbab24cf457b91 Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Tue, 17 Jan 2017 06:34:52 +0200 Subject: vfs: create vfs helper vfs_tmpfile() Factor out some common vfs bits from do_tmpfile() to be used by overlayfs for concurrent copy up. Signed-off-by: Amir Goldstein Cc: Al Viro Signed-off-by: Miklos Szeredi --- fs/namei.c | 68 +++++++++++++++++++++++++++++++++++++++----------------------- 1 file changed, 43 insertions(+), 25 deletions(-) (limited to 'fs/namei.c') diff --git a/fs/namei.c b/fs/namei.c index ad74877e1442..7d87699c3e2e 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -3353,13 +3353,50 @@ out: return error; } +struct dentry *vfs_tmpfile(struct dentry *dentry, umode_t mode, int open_flag) +{ + static const struct qstr name = QSTR_INIT("/", 1); + struct dentry *child = NULL; + struct inode *dir = dentry->d_inode; + struct inode *inode; + int error; + + /* we want directory to be writable */ + error = inode_permission(dir, MAY_WRITE | MAY_EXEC); + if (error) + goto out_err; + error = -EOPNOTSUPP; + if (!dir->i_op->tmpfile) + goto out_err; + error = -ENOMEM; + child = d_alloc(dentry, &name); + if (unlikely(!child)) + goto out_err; + error = dir->i_op->tmpfile(dir, child, mode); + if (error) + goto out_err; + error = -ENOENT; + inode = child->d_inode; + if (unlikely(!inode)) + goto out_err; + if (!(open_flag & O_EXCL)) { + spin_lock(&inode->i_lock); + inode->i_state |= I_LINKABLE; + spin_unlock(&inode->i_lock); + } + return child; + +out_err: + dput(child); + return ERR_PTR(error); +} +EXPORT_SYMBOL(vfs_tmpfile); + static int do_tmpfile(struct nameidata *nd, unsigned flags, const struct open_flags *op, struct file *file, int *opened) { - static const struct qstr name = QSTR_INIT("/", 1); struct dentry *child; - struct inode *dir; struct path path; int error = path_lookupat(nd, flags | LOOKUP_DIRECTORY, &path); if (unlikely(error)) @@ -3367,25 +3404,12 @@ static int do_tmpfile(struct nameidata *nd, unsigned flags, error = mnt_want_write(path.mnt); if (unlikely(error)) goto out; - dir = path.dentry->d_inode; - /* we want directory to be writable */ - error = inode_permission(dir, MAY_WRITE | MAY_EXEC); - if (error) - goto out2; - if (!dir->i_op->tmpfile) { - error = -EOPNOTSUPP; - goto out2; - } - child = d_alloc(path.dentry, &name); - if (unlikely(!child)) { - error = -ENOMEM; + child = vfs_tmpfile(path.dentry, op->mode, op->open_flag); + error = PTR_ERR(child); + if (unlikely(IS_ERR(child))) goto out2; - } dput(path.dentry); path.dentry = child; - error = dir->i_op->tmpfile(dir, child, op->mode); - if (error) - goto out2; audit_inode(nd->name, child, 0); /* Don't check for other permissions, the inode was just created */ error = may_open(&path, 0, op->open_flag); @@ -3396,14 +3420,8 @@ static int do_tmpfile(struct nameidata *nd, unsigned flags, if (error) goto out2; error = open_check_o_direct(file); - if (error) { + if (error) fput(file); - } else if (!(op->open_flag & O_EXCL)) { - struct inode *inode = file_inode(file); - spin_lock(&inode->i_lock); - inode->i_state |= I_LINKABLE; - spin_unlock(&inode->i_lock); - } out2: mnt_drop_write(path.mnt); out: -- cgit v1.2.3-55-g7522