The following generated no response on lkml so I gather it is a flawed concept, but I developed it in awareness of the prior attempts to hardwire _policy_ for COWfiles into the kernel, and I thought it would be a useful bridge until something better came along. Can someone please comment? It would help me be a more useful contributor. Thanks. Giving the O_COW flag to open() will return a special error, if IS_COW(inode) and write permissions are expressed or implied. COW-aware applications may set this flag and deal with this error according to some user defined policy. This will not change the semantics of any existing application or affect any kernel user of open_namei(); nor does it affect future applications unless they use O_COW. Filesystem level code is unimplemented except for an ext2 example. Signed-off-by: Carl Spalletta <cspalletta@xxxxxxxxx> --- fs/namei.c | 17 +++++++++++++++++ include/linux/fs.h | 3 +++ include/asm-generic/errno.h | 2 ++ include/linux/ext2_fs.h | 1 + fs/ext2/inode.c | 2 ++ 5 files changed, 25 insertions(+) ... [full patch on LKML] ... -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
