Merge tag 'pull-tmpfile' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs tmpfile updates from Al Viro:
 "Miklos' ->tmpfile() signature change; pass an unopened struct file to
  it, let it open the damn thing. Allows to add tmpfile support to FUSE"

* tag 'pull-tmpfile' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fuse: implement ->tmpfile()
  vfs: open inside ->tmpfile()
  vfs: move open right after ->tmpfile()
  vfs: make vfs_tmpfile() static
  ovl: use vfs_tmpfile_open() helper
  cachefiles: use vfs_tmpfile_open() helper
  cachefiles: only pass inode to *mark_inode_inuse() helpers
  cachefiles: tmpfile error handling cleanup
  hugetlbfs: cleanup mknod and tmpfile
  vfs: add vfs_tmpfile_open() helper

3 files changed, 70 insertions, 60 deletions

diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index 3ffea291c410..f436d8847f08 100644
--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -193,11 +193,11 @@ static int ovl_copy_fileattr(struct inode *inode, const struct path *old,
 	return ovl_real_fileattr_set(new, &newfa);
 }
 
-static int ovl_copy_up_data(struct ovl_fs *ofs, const struct path *old,
-			    const struct path *new, loff_t len)
+static int ovl_copy_up_file(struct ovl_fs *ofs, struct dentry *dentry,
+			    struct file *new_file, loff_t len)
 {
+	struct path datapath;
 	struct file *old_file;
-	struct file *new_file;
 	loff_t old_pos = 0;
 	loff_t new_pos = 0;
 	loff_t cloned;
@@ -206,23 +206,18 @@ static int ovl_copy_up_data(struct ovl_fs *ofs, const struct path *old,
 	bool skip_hole = false;
 	int error = 0;
 
-	if (len == 0)
-		return 0;
+	ovl_path_lowerdata(dentry, &datapath);
+	if (WARN_ON(datapath.dentry == NULL))
+		return -EIO;
 
-	old_file = ovl_path_open(old, O_LARGEFILE | O_RDONLY);
+	old_file = ovl_path_open(&datapath, O_LARGEFILE | O_RDONLY);
 	if (IS_ERR(old_file))
 		return PTR_ERR(old_file);
 
-	new_file = ovl_path_open(new, O_LARGEFILE | O_WRONLY);
-	if (IS_ERR(new_file)) {
-		error = PTR_ERR(new_file);
-		goto out_fput;
-	}
-
 	/* Try to use clone_file_range to clone up within the same fs */
 	cloned = do_clone_file_range(old_file, 0, new_file, 0, len, 0);
 	if (cloned == len)
-		goto out;
+		goto out_fput;
 	/* Couldn't clone, so now we try to copy the data */
 
 	/* Check if lower fs supports seek operation */
@@ -282,10 +277,8 @@ static int ovl_copy_up_data(struct ovl_fs *ofs, const struct path *old,
 
 		len -= bytes;
 	}
-out:
 	if (!error && ovl_should_sync(ofs))
 		error = vfs_fsync(new_file, 0);
-	fput(new_file);
 out_fput:
 	fput(old_file);
 	return error;
@@ -556,30 +549,31 @@ static int ovl_link_up(struct ovl_copy_up_ctx *c)
 	return err;
 }
 
-static int ovl_copy_up_inode(struct ovl_copy_up_ctx *c, struct dentry *temp)
+static int ovl_copy_up_data(struct ovl_copy_up_ctx *c, const struct path *temp)
 {
 	struct ovl_fs *ofs = OVL_FS(c->dentry->d_sb);
-	struct inode *inode = d_inode(c->dentry);
-	struct path upperpath, datapath;
+	struct file *new_file;
 	int err;
 
-	ovl_path_upper(c->dentry, &upperpath);
-	if (WARN_ON(upperpath.dentry != NULL))
-		return -EIO;
+	if (!S_ISREG(c->stat.mode) || c->metacopy || !c->stat.size)
+		return 0;
 
-	upperpath.dentry = temp;
+	new_file = ovl_path_open(temp, O_LARGEFILE | O_WRONLY);
+	if (IS_ERR(new_file))
+		return PTR_ERR(new_file);
 
-	/*
-	 * Copy up data first and then xattrs. Writing data after
-	 * xattrs will remove security.capability xattr automatically.
-	 */
-	if (S_ISREG(c->stat.mode) && !c->metacopy) {
-		ovl_path_lowerdata(c->dentry, &datapath);
-		err = ovl_copy_up_data(ofs, &datapath, &upperpath,
-				       c->stat.size);
-		if (err)
-			return err;
-	}
+	err = ovl_copy_up_file(ofs, c->dentry, new_file, c->stat.size);
+	fput(new_file);
+
+	return err;
+}
+
+static int ovl_copy_up_metadata(struct ovl_copy_up_ctx *c, struct dentry *temp)
+{
+	struct ovl_fs *ofs = OVL_FS(c->dentry->d_sb);
+	struct inode *inode = d_inode(c->dentry);
+	struct path upperpath = { .mnt = ovl_upper_mnt(ofs), .dentry = temp };
+	int err;
 
 	err = ovl_copy_xattr(c->dentry->d_sb, &c->lowerpath, temp);
 	if (err)
@@ -662,6 +656,7 @@ static int ovl_copy_up_workdir(struct ovl_copy_up_ctx *c)
 	struct ovl_fs *ofs = OVL_FS(c->dentry->d_sb);
 	struct inode *inode;
 	struct inode *udir = d_inode(c->destdir), *wdir = d_inode(c->workdir);
+	struct path path = { .mnt = ovl_upper_mnt(ofs) };
 	struct dentry *temp, *upper;
 	struct ovl_cu_creds cc;
 	int err;
@@ -688,7 +683,16 @@ static int ovl_copy_up_workdir(struct ovl_copy_up_ctx *c)
 	if (IS_ERR(temp))
 		goto unlock;
 
-	err = ovl_copy_up_inode(c, temp);
+	/*
+	 * Copy up data first and then xattrs. Writing data after
+	 * xattrs will remove security.capability xattr automatically.
+	 */
+	path.dentry = temp;
+	err = ovl_copy_up_data(c, &path);
+	if (err)
+		goto cleanup;
+
+	err = ovl_copy_up_metadata(c, temp);
 	if (err)
 		goto cleanup;
 
@@ -732,6 +736,7 @@ static int ovl_copy_up_tmpfile(struct ovl_copy_up_ctx *c)
 	struct ovl_fs *ofs = OVL_FS(c->dentry->d_sb);
 	struct inode *udir = d_inode(c->destdir);
 	struct dentry *temp, *upper;
+	struct file *tmpfile;
 	struct ovl_cu_creds cc;
 	int err;
 
@@ -739,15 +744,22 @@ static int ovl_copy_up_tmpfile(struct ovl_copy_up_ctx *c)
 	if (err)
 		return err;
 
-	temp = ovl_do_tmpfile(ofs, c->workdir, c->stat.mode);
+	tmpfile = ovl_do_tmpfile(ofs, c->workdir, c->stat.mode);
 	ovl_revert_cu_creds(&cc);
 
-	if (IS_ERR(temp))
-		return PTR_ERR(temp);
+	if (IS_ERR(tmpfile))
+		return PTR_ERR(tmpfile);
 
-	err = ovl_copy_up_inode(c, temp);
+	temp = tmpfile->f_path.dentry;
+	if (!c->metacopy && c->stat.size) {
+		err = ovl_copy_up_file(ofs, c->dentry, tmpfile, c->stat.size);
+		if (err)
+			return err;
+	}
+
+	err = ovl_copy_up_metadata(c, temp);
 	if (err)
-		goto out_dput;
+		goto out_fput;
 
 	inode_lock_nested(udir, I_MUTEX_PARENT);
 
@@ -761,16 +773,14 @@ static int ovl_copy_up_tmpfile(struct ovl_copy_up_ctx *c)
 	inode_unlock(udir);
 
 	if (err)
-		goto out_dput;
+		goto out_fput;
 
 	if (!c->metacopy)
 		ovl_set_upperdata(d_inode(c->dentry));
-	ovl_inode_update(d_inode(c->dentry), temp);
+	ovl_inode_update(d_inode(c->dentry), dget(temp));
 
-	return 0;
-
-out_dput:
-	dput(temp);
+out_fput:
+	fput(tmpfile);
 	return err;
 }
 
@@ -899,7 +909,7 @@ static ssize_t ovl_getxattr_value(const struct path *path, char *name, char **va
 static int ovl_copy_up_meta_inode_data(struct ovl_copy_up_ctx *c)
 {
 	struct ovl_fs *ofs = OVL_FS(c->dentry->d_sb);
-	struct path upperpath, datapath;
+	struct path upperpath;
 	int err;
 	char *capability = NULL;
 	ssize_t cap_size;
@@ -908,10 +918,6 @@ static int ovl_copy_up_meta_inode_data(struct ovl_copy_up_ctx *c)
 	if (WARN_ON(upperpath.dentry == NULL))
 		return -EIO;
 
-	ovl_path_lowerdata(c->dentry, &datapath);
-	if (WARN_ON(datapath.dentry == NULL))
-		return -EIO;
-
 	if (c->stat.size) {
 		err = cap_size = ovl_getxattr_value(&upperpath, XATTR_NAME_CAPS,
 						    &capability);
@@ -919,7 +925,7 @@ static int ovl_copy_up_meta_inode_data(struct ovl_copy_up_ctx *c)
 			goto out;
 	}
 
-	err = ovl_copy_up_data(ofs, &datapath, &upperpath, c->stat.size);
+	err = ovl_copy_up_data(c, &upperpath);
 	if (err)
 		goto out_free;
 
diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h
index 59624521eeb2..eee8f08d32b6 100644
--- a/fs/overlayfs/overlayfs.h
+++ b/fs/overlayfs/overlayfs.h
@@ -310,14 +310,16 @@ static inline int ovl_do_whiteout(struct ovl_fs *ofs,
 	return err;
 }
 
-static inline struct dentry *ovl_do_tmpfile(struct ovl_fs *ofs,
-					    struct dentry *dentry, umode_t mode)
+static inline struct file *ovl_do_tmpfile(struct ovl_fs *ofs,
+					  struct dentry *dentry, umode_t mode)
 {
-	struct dentry *ret = vfs_tmpfile(ovl_upper_mnt_userns(ofs), dentry, mode, 0);
-	int err = PTR_ERR_OR_ZERO(ret);
+	struct path path = { .mnt = ovl_upper_mnt(ofs), .dentry = dentry };
+	struct file *file = vfs_tmpfile_open(ovl_upper_mnt_userns(ofs), &path, mode,
+					O_LARGEFILE | O_WRONLY, current_cred());
+	int err = PTR_ERR_OR_ZERO(file);
 
 	pr_debug("tmpfile(%pd2, 0%o) = %i\n", dentry, mode, err);
-	return ret;
+	return file;
 }
 
 static inline struct dentry *ovl_lookup_upper(struct ovl_fs *ofs,
diff --git a/fs/overlayfs/super.c b/fs/overlayfs/super.c
index 9ca98bea8e18..a29a8afe9b26 100644
--- a/fs/overlayfs/super.c
+++ b/fs/overlayfs/super.c
@@ -15,6 +15,7 @@
 #include <linux/seq_file.h>
 #include <linux/posix_acl_xattr.h>
 #include <linux/exportfs.h>
+#include <linux/file.h>
 #include "overlayfs.h"
 
 MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
@@ -1369,7 +1370,8 @@ static int ovl_make_workdir(struct super_block *sb, struct ovl_fs *ofs,
 			    const struct path *workpath)
 {
 	struct vfsmount *mnt = ovl_upper_mnt(ofs);
-	struct dentry *temp, *workdir;
+	struct dentry *workdir;
+	struct file *tmpfile;
 	bool rename_whiteout;
 	bool d_type;
 	int fh_type;
@@ -1405,10 +1407,10 @@ static int ovl_make_workdir(struct super_block *sb, struct ovl_fs *ofs,
 		pr_warn("upper fs needs to support d_type.\n");
 
 	/* Check if upper/work fs supports O_TMPFILE */
-	temp = ovl_do_tmpfile(ofs, ofs->workdir, S_IFREG | 0);
-	ofs->tmpfile = !IS_ERR(temp);
+	tmpfile = ovl_do_tmpfile(ofs, ofs->workdir, S_IFREG | 0);
+	ofs->tmpfile = !IS_ERR(tmpfile);
 	if (ofs->tmpfile)
-		dput(temp);
+		fput(tmpfile);
 	else
 		pr_warn("upper fs does not support tmpfile.\n");