On Jul 24, 2014, at 7:50 PM, JP Abgrall [off-list ref] wrote:

On Thu, Jul 24, 2014 at 5:08 AM, Dave Chinner [off-list ref] wrote:

quoted

On Wed, Jul 23, 2014 at 04:47:18PM -0700, JP Abgrall wrote:

quoted

+#define FIDTRIM      _IOWR('X', 122, struct fstrim_range)    /* Deep discard trim */

The 'X' ioctl namespace is actually XFS's ioctl namespace. FIDTRIM
should be in the 'f' namespace

Ok.
How should the next sequence number be handled?
Go with ('f', 122,...) after FITRIM, or go with ('f', 12,...) after
FS_IOC_FIEMAP ('f' namepsace)?

Please leave the low 'f' values for ext2/3/4 (where FS_IOC_[GS]ETFLAGS,
FS_IOC_[GS]ETFLAGS, and FS_IOC_FIEMAPand came from, and use high 'f'
numbers, maybe starting at 128 (?) for generic ioctl values.

Cheers, Andreas