X-Git-Url: http://pileus.org/git/?a=blobdiff_plain;f=Documentation%2Ffilesystems%2Fporting;h=f9547a5c187bd16f849e6913fdb6287a411b1054;hb=1e2317350971c8b01e6adddc798a00e9bcc1a440;hp=a7e9746ee7ea44934c017b4c2a26ef6df9361db8;hpb=82062e7b50280bcf0feca70ac35a44f375602976;p=~andy%2Flinux

diff --git a/Documentation/filesystems/porting b/Documentation/filesystems/porting
index a7e9746ee7e..f9547a5c187 100644
--- a/Documentation/filesystems/porting
+++ b/Documentation/filesystems/porting
@@ -273,3 +273,21 @@ it's safe to remove it.  If you don't need it, remove it.
 deliberate; as soon as struct block_device * is propagated in a reasonable
 way by that code fixing will become trivial; until then nothing can be
 done.
+
+[mandatory]
+
+	block truncatation on error exit from ->write_begin, and ->direct_IO
+moved from generic methods (block_write_begin, cont_write_begin,
+nobh_write_begin, blockdev_direct_IO*) to callers.  Take a look at
+ext2_write_failed and callers for an example.
+
+[mandatory]
+
+	->truncate is going away.  The whole truncate sequence needs to be
+implemented in ->setattr, which is now mandatory for filesystems
+implementing on-disk size changes.  Start with a copy of the old inode_setattr
+and vmtruncate, and the reorder the vmtruncate + foofs_vmtruncate sequence to
+be in order of zeroing blocks using block_truncate_page or similar helpers,
+size update and on finally on-disk truncation which should not fail.
+inode_change_ok now includes the size checks for ATTR_SIZE and must be called
+in the beginning of ->setattr unconditionally.