make ->atomic_open() return int

Change of calling conventions:
old		new
NULL		1
file		0
ERR_PTR(-ve)	-ve

Caller *knows* that struct file *; no need to return it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

10 files changed, 90 insertions, 98 deletions

diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index de626b3b342..62ce8daefa9 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -856,7 +856,7 @@ error:
 	return ERR_PTR(result);
 }
 
-static struct file *
+static int
 v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,
 		     struct opendata *od, unsigned flags, umode_t mode,
 		     int *opened)
@@ -872,7 +872,7 @@ v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,
 	if (d_unhashed(dentry)) {
 		res = v9fs_vfs_lookup(dir, dentry, NULL);
 		if (IS_ERR(res))
-			return ERR_CAST(res);
+			return PTR_ERR(res);
 
 		if (res)
 			dentry = res;
@@ -881,7 +881,7 @@ v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,
 	/* Only creates */
 	if (!(flags & O_CREAT) || dentry->d_inode) {
 		finish_no_open(od, res);
-		return NULL;
+		return 1;
 	}
 
 	err = 0;
@@ -933,13 +933,11 @@ v9fs_vfs_atomic_open(struct inode *dir, struct dentry *dentry,
 	*opened |= FILE_CREATED;
 out:
 	dput(res);
-	return filp;
+	return err;
 
 error:
 	if (fid)
 		p9_client_clunk(fid);
-
-	filp = ERR_PTR(err);
 	goto out;
 }
 
diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index 3db55471bc9..69f05109f75 100644
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -240,7 +240,7 @@ v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, umode_t omode,
 	return v9fs_vfs_mknod_dotl(dir, dentry, omode, 0);
 }
 
-static struct file *
+static int
 v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
 			  struct opendata *od, unsigned flags, umode_t omode,
 			  int *opened)
@@ -262,7 +262,7 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
 	if (d_unhashed(dentry)) {
 		res = v9fs_vfs_lookup(dir, dentry, NULL);
 		if (IS_ERR(res))
-			return ERR_CAST(res);
+			return PTR_ERR(res);
 
 		if (res)
 			dentry = res;
@@ -271,7 +271,7 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
 	/* Only creates */
 	if (!(flags & O_CREAT) || dentry->d_inode) {
 		finish_no_open(od, res);
-		return NULL;
+		return 1;
 	}
 
 	v9ses = v9fs_inode2v9ses(dir);
@@ -284,7 +284,7 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
 	if (IS_ERR(dfid)) {
 		err = PTR_ERR(dfid);
 		p9_debug(P9_DEBUG_VFS, "fid lookup failed %d\n", err);
-		goto err_return;
+		goto out;
 	}
 
 	/* clone a fid to use for creation */
@@ -292,7 +292,7 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
 	if (IS_ERR(ofid)) {
 		err = PTR_ERR(ofid);
 		p9_debug(P9_DEBUG_VFS, "p9_client_walk failed %d\n", err);
-		goto err_return;
+		goto out;
 	}
 
 	gid = v9fs_get_fsgid_for_create(dir);
@@ -370,7 +370,7 @@ v9fs_vfs_atomic_open_dotl(struct inode *dir, struct dentry *dentry,
 	*opened |= FILE_CREATED;
 out:
 	dput(res);
-	return filp;
+	return err;
 
 error:
 	if (fid)
@@ -379,8 +379,6 @@ err_clunk_old_fid:
 	if (ofid)
 		p9_client_clunk(ofid);
 	v9fs_set_create_acl(NULL, &dacl, &pacl);
-err_return:
-	filp = ERR_PTR(err);
 	goto out;
 }
 
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 81e5e908df9..d8bfabeeaa2 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -634,21 +634,20 @@ static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
 	return dentry;
 }
 
-struct file *ceph_atomic_open(struct inode *dir, struct dentry *dentry,
-			      struct opendata *od, unsigned flags, umode_t mode,
-			      int *opened)
+int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
+		     struct opendata *od, unsigned flags, umode_t mode,
+		     int *opened)
 {
 	int err;
 	struct dentry *res = NULL;
-	struct file *filp;
 
 	if (!(flags & O_CREAT)) {
 		if (dentry->d_name.len > NAME_MAX)
-			return ERR_PTR(-ENAMETOOLONG);
+			return -ENAMETOOLONG;
 
 		err = ceph_init_dentry(dentry);
 		if (err < 0)
-			return ERR_PTR(err);
+			return err;
 
 		return ceph_lookup_open(dir, dentry, od, flags, mode, opened);
 	}
@@ -656,7 +655,7 @@ struct file *ceph_atomic_open(struct inode *dir, struct dentry *dentry,
 	if (d_unhashed(dentry)) {
 		res = ceph_lookup(dir, dentry, NULL);
 		if (IS_ERR(res))
-			return ERR_CAST(res);
+			return PTR_ERR(res);
 
 		if (res)
 			dentry = res;
@@ -665,14 +664,14 @@ struct file *ceph_atomic_open(struct inode *dir, struct dentry *dentry,
 	/* We don't deal with positive dentries here */
 	if (dentry->d_inode) {
 		finish_no_open(od, res);
-		return NULL;
+		return 1;
 	}
 
 	*opened |= FILE_CREATED;
-	filp = ceph_lookup_open(dir, dentry, od, flags, mode, opened);
+	err = ceph_lookup_open(dir, dentry, od, flags, mode, opened);
 	dput(res);
 
-	return filp;
+	return err;
 }
 
 /*
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 4c304a90d04..b8cc3ee5401 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -213,9 +213,9 @@ out:
  * may_open() fails, the struct *file gets cleaned up (i.e.
  * ceph_release gets called).  So fear not!
  */
-struct file *ceph_lookup_open(struct inode *dir, struct dentry *dentry,
-			      struct opendata *od, unsigned flags, umode_t mode,
-			      int *opened)
+int ceph_lookup_open(struct inode *dir, struct dentry *dentry,
+		     struct opendata *od, unsigned flags, umode_t mode,
+		     int *opened)
 {
 	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 	struct ceph_mds_client *mdsc = fsc->mdsc;
@@ -230,7 +230,7 @@ struct file *ceph_lookup_open(struct inode *dir, struct dentry *dentry,
 	/* do the open */
 	req = prepare_open_request(dir->i_sb, flags, mode);
 	if (IS_ERR(req))
-		return ERR_CAST(req);
+		return PTR_ERR(req);
 	req->r_dentry = dget(dentry);
 	req->r_num_caps = 2;
 	if (flags & O_CREAT) {
@@ -257,10 +257,10 @@ out:
 	dout("ceph_lookup_open result=%p\n", ret);
 
 	if (IS_ERR(ret))
-		return ERR_CAST(ret);
+		return PTR_ERR(ret);
 
 	dput(ret);
-	return err ? ERR_PTR(err) : file;
+	return err;
 }
 
 int ceph_release(struct inode *inode, struct file *file)
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index f9a325108b4..f7e8e82ec47 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -806,9 +806,9 @@ extern int ceph_copy_from_page_vector(struct page **pages,
 				    loff_t off, size_t len);
 extern struct page **ceph_alloc_page_vector(int num_pages, gfp_t flags);
 extern int ceph_open(struct inode *inode, struct file *file);
-extern struct file *ceph_lookup_open(struct inode *dir, struct dentry *dentry,
-				     struct opendata *od, unsigned flags,
-				     umode_t mode, int *opened);
+extern int ceph_lookup_open(struct inode *dir, struct dentry *dentry,
+			     struct opendata *od, unsigned flags,
+			     umode_t mode, int *opened);
 extern int ceph_release(struct inode *inode, struct file *filp);
 
 /* dir.c */
diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h
index 92a7c3d8a03..58d9aca46a4 100644
--- a/fs/cifs/cifsfs.h
+++ b/fs/cifs/cifsfs.h
@@ -46,9 +46,9 @@ extern const struct inode_operations cifs_dir_inode_ops;
 extern struct inode *cifs_root_iget(struct super_block *);
 extern int cifs_create(struct inode *, struct dentry *, umode_t,
 		       struct nameidata *);
-extern struct file *cifs_atomic_open(struct inode *, struct dentry *,
-				     struct opendata *, unsigned, umode_t,
-				     int *);
+extern int cifs_atomic_open(struct inode *, struct dentry *,
+			    struct opendata *, unsigned, umode_t,
+			    int *);
 extern struct dentry *cifs_lookup(struct inode *, struct dentry *,
 				  struct nameidata *);
 extern int cifs_unlink(struct inode *dir, struct dentry *dentry);
diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c
index 6cdf23fd70e..8ca70b102b9 100644
--- a/fs/cifs/dir.c
+++ b/fs/cifs/dir.c
@@ -376,7 +376,7 @@ out:
 	return rc;
 }
 
-struct file *
+int
 cifs_atomic_open(struct inode *inode, struct dentry *direntry,
 		 struct opendata *od, unsigned oflags, umode_t mode,
 		 int *opened)
@@ -403,15 +403,15 @@ cifs_atomic_open(struct inode *inode, struct dentry *direntry,
 	if (!(oflags & O_CREAT)) {
 		struct dentry *res = cifs_lookup(inode, direntry, NULL);
 		if (IS_ERR(res))
-			return ERR_CAST(res);
+			return PTR_ERR(res);
 
 		finish_no_open(od, res);
-		return NULL;
+		return 1;
 	}
 
 	rc = check_name(direntry);
 	if (rc)
-		return ERR_PTR(rc);
+		return rc;
 
 	xid = GetXid();
 
@@ -428,13 +428,12 @@ cifs_atomic_open(struct inode *inode, struct dentry *direntry,
 	rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
 			    &oplock, &fileHandle, opened);
 
-	if (rc) {
-		filp = ERR_PTR(rc);
+	if (rc)
 		goto out;
-	}
 
 	filp = finish_open(od, direntry, generic_file_open, opened);
 	if (IS_ERR(filp)) {
+		rc = PTR_ERR(filp);
 		CIFSSMBClose(xid, tcon, fileHandle);
 		goto out;
 	}
@@ -443,14 +442,14 @@ cifs_atomic_open(struct inode *inode, struct dentry *direntry,
 	if (pfile_info == NULL) {
 		CIFSSMBClose(xid, tcon, fileHandle);
 		fput(filp);
-		filp = ERR_PTR(-ENOMEM);
+		rc = -ENOMEM;
 	}
 
 out:
 	cifs_put_tlink(tlink);
 free_xid:
 	FreeXid(xid);
-	return filp;
+	return rc;
 }
 
 int cifs_create(struct inode *inode, struct dentry *direntry, umode_t mode,
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index 345f78ee5c9..8a9ca09e87d 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -369,9 +369,9 @@ static struct dentry *fuse_lookup(struct inode *dir, struct dentry *entry,
  * If the filesystem doesn't support this, then fall back to separate
  * 'mknod' + 'open' requests.
  */
-static struct file *fuse_create_open(struct inode *dir, struct dentry *entry,
-				     struct opendata *od, unsigned flags,
-				     umode_t mode, int *opened)
+static int fuse_create_open(struct inode *dir, struct dentry *entry,
+			    struct opendata *od, unsigned flags,
+			    umode_t mode, int *opened)
 {
 	int err;
 	struct inode *inode;
@@ -452,12 +452,14 @@ static struct file *fuse_create_open(struct inode *dir, struct dentry *entry,
 	fuse_invalidate_attr(dir);
 	file = finish_open(od, entry, generic_file_open, opened);
 	if (IS_ERR(file)) {
+		err = PTR_ERR(file);
 		fuse_sync_release(ff, flags);
 	} else {
 		file->private_data = fuse_file_get(ff);
 		fuse_finish_open(inode, file);
+		err = 0;
 	}
-	return file;
+	return err;
 
 out_free_ff:
 	fuse_file_free(ff);
@@ -466,23 +468,22 @@ out_put_request:
 out_put_forget_req:
 	kfree(forget);
 out_err:
-	return ERR_PTR(err);
+	return err;
 }
 
 static int fuse_mknod(struct inode *, struct dentry *, umode_t, dev_t);
-static struct file *fuse_atomic_open(struct inode *dir, struct dentry *entry,
-				     struct opendata *od, unsigned flags,
-				     umode_t mode, int *opened)
+static int fuse_atomic_open(struct inode *dir, struct dentry *entry,
+			    struct opendata *od, unsigned flags,
+			    umode_t mode, int *opened)
 {
 	int err;
 	struct fuse_conn *fc = get_fuse_conn(dir);
-	struct file *file;
 	struct dentry *res = NULL;
 
 	if (d_unhashed(entry)) {
 		res = fuse_lookup(dir, entry, NULL);
 		if (IS_ERR(res))
-			return ERR_CAST(res);
+			return PTR_ERR(res);
 
 		if (res)
 			entry = res;
@@ -497,24 +498,22 @@ static struct file *fuse_atomic_open(struct inode *dir, struct dentry *entry,
 	if (fc->no_create)
 		goto mknod;
 
-	file = fuse_create_open(dir, entry, od, flags, mode, opened);
-	if (PTR_ERR(file) == -ENOSYS) {
+	err = fuse_create_open(dir, entry, od, flags, mode, opened);
+	if (err == -ENOSYS) {
 		fc->no_create = 1;
 		goto mknod;
 	}
 out_dput:
 	dput(res);
-	return file;
+	return err;
 
 mknod:
 	err = fuse_mknod(dir, entry, mode, 0);
-	if (err) {
-		file = ERR_PTR(err);
+	if (err)
 		goto out_dput;
-	}
 no_open:
 	finish_no_open(od, res);
-	return NULL;
+	return 1;
 }
 
 /*
diff --git a/fs/namei.c b/fs/namei.c
index 18b9326d951..f0dae0057ec 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2204,7 +2204,7 @@ static struct file *atomic_open(struct nameidata *nd, struct dentry *dentry,
 	umode_t mode;
 	int error;
 	int acc_mode;
-	struct file *filp;
+	struct file *filp = NULL;
 	int create_error = 0;
 	struct dentry *const DENTRY_NOT_SET = (void *) -1UL;
 
@@ -2271,14 +2271,15 @@ static struct file *atomic_open(struct nameidata *nd, struct dentry *dentry,
 
 	od->dentry = DENTRY_NOT_SET;
 	od->mnt = nd->path.mnt;
-	filp = dir->i_op->atomic_open(dir, dentry, od, open_flag, mode,
+	error = dir->i_op->atomic_open(dir, dentry, od, open_flag, mode,
 				      opened);
-	if (IS_ERR(filp)) {
+	if (error < 0) {
 		if (WARN_ON(od->dentry != DENTRY_NOT_SET))
 			dput(od->dentry);
 
-		if (create_error && PTR_ERR(filp) == -ENOENT)
-			filp = ERR_PTR(create_error);
+		if (create_error && error == -ENOENT)
+			error = create_error;
+		filp = ERR_PTR(error);
 		goto out;
 	}
 
@@ -2288,7 +2289,7 @@ static struct file *atomic_open(struct nameidata *nd, struct dentry *dentry,
 		acc_mode = MAY_OPEN;
 	}
 
-	if (!filp) {
+	if (error) {	/* returned 1, that is */
 		if (WARN_ON(od->dentry == DENTRY_NOT_SET)) {
 			filp = ERR_PTR(-EIO);
 			goto out;
@@ -2304,6 +2305,7 @@ static struct file *atomic_open(struct nameidata *nd, struct dentry *dentry,
 	 * We didn't have the inode before the open, so check open permission
 	 * here.
 	 */
+	filp = od->filp;
 	error = may_open(&filp->f_path, acc_mode, open_flag);
 	if (error) {
 		fput(filp);
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 6deb2549ead..b56f4b36ed4 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -111,9 +111,9 @@ const struct inode_operations nfs3_dir_inode_operations = {
 
 #ifdef CONFIG_NFS_V4
 
-static struct file *nfs_atomic_open(struct inode *, struct dentry *,
-				    struct opendata *, unsigned, umode_t,
-				    int *);
+static int nfs_atomic_open(struct inode *, struct dentry *,
+			   struct opendata *, unsigned, umode_t,
+			   int *);
 const struct inode_operations nfs4_dir_inode_operations = {
 	.create		= nfs_create,
 	.lookup		= nfs_lookup,
@@ -1387,10 +1387,10 @@ static int do_open(struct inode *inode, struct file *filp)
 	return 0;
 }
 
-static struct file *nfs_finish_open(struct nfs_open_context *ctx,
-				    struct dentry *dentry,
-				    struct opendata *od, unsigned open_flags,
-				    int *opened)
+static int nfs_finish_open(struct nfs_open_context *ctx,
+			   struct dentry *dentry,
+			   struct opendata *od, unsigned open_flags,
+			   int *opened)
 {
 	struct file *filp;
 	int err;
@@ -1403,30 +1403,31 @@ static struct file *nfs_finish_open(struct nfs_open_context *ctx,
 	/* If the open_intent is for execute, we have an extra check to make */
 	if (ctx->mode & FMODE_EXEC) {
 		err = nfs_may_open(dentry->d_inode, ctx->cred, open_flags);
-		if (err < 0) {
-			filp = ERR_PTR(err);
+		if (err < 0)
 			goto out;
-		}
 	}
 
 	filp = finish_open(od, dentry, do_open, opened);
-	if (!IS_ERR(filp))
-		nfs_file_set_open_context(filp, ctx);
+	if (IS_ERR(filp)) {
+		err = PTR_ERR(filp);
+		goto out;
+	}
+	nfs_file_set_open_context(filp, ctx);
+	err = 0;
 
 out:
 	put_nfs_open_context(ctx);
-	return filp;
+	return err;
 }
 
-static struct file *nfs_atomic_open(struct inode *dir, struct dentry *dentry,
-				    struct opendata *od, unsigned open_flags,
-				    umode_t mode, int *opened)
+static int nfs_atomic_open(struct inode *dir, struct dentry *dentry,
+			    struct opendata *od, unsigned open_flags,
+			    umode_t mode, int *opened)
 {
 	struct nfs_open_context *ctx;
 	struct dentry *res;
 	struct iattr attr = { .ia_valid = ATTR_OPEN };
 	struct inode *inode;
-	struct file *filp;
 	int err;
 
 	/* Expect a negative dentry */
@@ -1437,21 +1438,19 @@ static struct file *nfs_atomic_open(struct inode *dir, struct dentry *dentry,
 
 	/* NFS only supports OPEN on regular files */
 	if ((open_flags & O_DIRECTORY)) {
-		err = -ENOENT;
 		if (!d_unhashed(dentry)) {
 			/*
 			 * Hashed negative dentry with O_DIRECTORY: dentry was
 			 * revalidated and is fine, no need to perform lookup
 			 * again
 			 */
-			goto out_err;
+			return -ENOENT;
 		}
 		goto no_open;
 	}
 
-	err = -ENAMETOOLONG;
 	if (dentry->d_name.len > NFS_SERVER(dir)->namelen)
-		goto out_err;
+		return -ENAMETOOLONG;
 
 	if (open_flags & O_CREAT) {
 		attr.ia_valid |= ATTR_MODE;
@@ -1465,7 +1464,7 @@ static struct file *nfs_atomic_open(struct inode *dir, struct dentry *dentry,
 	ctx = create_nfs_open_context(dentry, open_flags);
 	err = PTR_ERR(ctx);
 	if (IS_ERR(ctx))
-		goto out_err;
+		goto out;
 
 	nfs_block_sillyrename(dentry->d_parent);
 	inode = NFS_PROTO(dir)->open_context(dir, ctx, open_flags, &attr);
@@ -1489,7 +1488,7 @@ static struct file *nfs_atomic_open(struct inode *dir, struct dentry *dentry,
 		default:
 			break;
 		}
-		goto out_err;
+		goto out;
 	}
 	res = d_add_unique(dentry, inode);
 	if (res != NULL)
@@ -1498,22 +1497,20 @@ static struct file *nfs_atomic_open(struct inode *dir, struct dentry *dentry,
 	nfs_unblock_sillyrename(dentry->d_parent);
 	nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
 
-	filp = nfs_finish_open(ctx, dentry, od, open_flags, opened);
+	err = nfs_finish_open(ctx, dentry, od, open_flags, opened);
 
 	dput(res);
-	return filp;
-
-out_err:
-	return ERR_PTR(err);
+out:
+	return err;
 
 no_open:
 	res = nfs_lookup(dir, dentry, NULL);
 	err = PTR_ERR(res);
 	if (IS_ERR(res))
-		goto out_err;
+		goto out;
 
 	finish_no_open(od, res);
-	return NULL;
+	return 1;
 }
 
 static int nfs4_lookup_revalidate(struct dentry *dentry, struct nameidata *nd)