From: Al Viro <v...@zeniv.linux.org.uk>
Signed-off-by: Al Viro <v...@zeniv.linux.org.uk>
---
Documentation/filesystems/porting | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/Documentation/filesystems/porting
b/Documentation/filesystems/porting
index c68ea9294b5f..77e2d623e115 100644
--- a/Documentation/filesystems/porting
+++ b/Documentation/filesystems/porting
@@ -610,3 +610,15 @@ in your dentry operations instead.
value for 'called finish_no_open(), open it yourself' case has become
0, not 1. Since finish_no_open() itself is returning 0 now, that part
does not need any changes in ->atomic_open() instances.
+--
+[mandatory]
+ alloc_file() has become static now; two wrappers are to be used instead.
+ alloc_file_pseudo(inode, vfsmount, name, mode, ops) is for the cases
+ when dentry needs to be created; that's the majority of old alloc_file()
+ users. Calling conventions: on success a reference to new struct file
+ is returned and callers reference to inode is subsumed by that. On
+ failure, ERR_PTR() is returned and no caller's references are affected,
+ so the caller needs to drop the inode reference it held.
+ alloc_file_clone(file, mode, ops) does not affect any caller's
references.
+ On success you get a new struct file sharing the mount/dentry with the
+ original, on failure - ERR_PTR().
--
2.11.0
