On Tue, Feb 17, 2015 at 12:47:48AM +0900, Namjae Jeon wrote:

quoted

From: Namjae Jeon <redacted>

FALLOC_FL_INSERT_RANGE command is the opposite command of
FALLOC_FL_COLLAPSE_RANGE that is needed for advertisers or someone who want to
add some data in the middle of file. FALLOC_FL_INSERT_RANGE will create space
for writing new data within a file after shifting extents to right as given
length. and this command also has same limitation as FALLOC_FL_COLLAPSE_RANGE,
that is block boundary and use ftruncate(2) for crosses EOF.

Signed-off-by: Namjae Jeon <redacted>
Signed-off-by: Ashish Sangwan <redacted>
Cc: Brian Foster<redacted>
---
 fs/open.c                   |    8 +++++++-
 include/uapi/linux/falloc.h |   17 +++++++++++++++++
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/fs/open.c b/fs/open.c
index 813be03..762fb45 100644
--- a/fs/open.c
+++ b/fs/open.c

@@ -232,7 +232,8 @@ int vfs_fallocate(struct file *file, int mode, loff_t offset, loff_t len)

 	/* Return error if mode is not supported */
 	if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE |
-		     FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE))
+		     FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE |
+		     FALLOC_FL_INSERT_RANGE))
 		return -EOPNOTSUPP;

Can we create a FALLOC_FL_SUPPORTED_MASK define in falloc.h
so that we only need to add new flags to the mask in rather than
change this code every time we add a new flag?

Sure, I will do it. and share the patch with the others you gave me review points soon.

Thanks for review!

Cheers,

Dave.
--
Dave Chinner
david@fromorbit.com