Hello Jan, On 18 October 2014 at 17:22, Jan Chaloupka <jchaloup@xxxxxxxxxx> wrote: > As from upstream commit: > > commit 3f31d07571eeea18a7d34db9af21d2285b807a17 > Author: Hugh Dickins <hughd@xxxxxxxxxx> > Date: Tue May 29 15:06:40 2012 -0700 > > mm/fs: route MADV_REMOVE to FALLOC_FL_PUNCH_HOLE > > Now tmpfs supports hole-punching via fallocate(), switch madvise_remove() > to use do_fallocate() instead of vmtruncate_range(): which extends > madvise(,,MADV_REMOVE) support from tmpfs to ext4, ocfs2 and xfs. > > madvise(,,MADV_REMOVE) support was extended by ext4, ocfs2 and xfs. > > bug report: https://bugzilla.redhat.com/show_bug.cgi?id=1120294 > > Justification from Rafael Aquini: > Well, that code is committed in kernel since v3.5 (2012) and it surely is > the expected behaviour since. It seems to me that madvise(2) man page text > for MADV_REMOVE just got out-of-date in that regard. > > This patch mentions this support in madvise.2 man page. > > Reworded and corrected by Michael Kerrisk and Hugh Dickins. Thank you. Sorry for the delay. I've applied this patch (and tweaked it a little, but not in essential details). Not yet pushed to kernel.,org yet. Cheers, Michael > Signed-off-by: Jan Chaloupka <jchaloup@xxxxxxxxxx> > --- > man2/madvise.2 | 17 ++++++++++++----- > 1 file changed, 12 insertions(+), 5 deletions(-) > > diff --git a/man2/madvise.2 b/man2/madvise.2 > index 032ead7..b955864 100644 > --- a/man2/madvise.2 > +++ b/man2/madvise.2 > @@ -101,11 +101,18 @@ without an underlying file. > .BR MADV_REMOVE " (since Linux 2.6.16)" > Free up a given range of pages > and its associated backing store. > -Currently, > -.\" 2.6.18-rc5 > -only shmfs/tmpfs supports this; other filesystems return with the > -error > -.BR ENOSYS . > +Originally, only shmfs/tmpfs supported this; but since Linux 3.5, > +any filesystem which supports the > +.BR fallocate(2) > +mode > +.BR FALLOC_FL_PUNCH_HOLE > +also supports the > +.BR madvise(2) > +advice > +.BR MADV_REMOVE . > +Other filesystems return with the > +.BR EOPNOTSUPP > +error. > .\" Databases want to use this feature to drop a section of their > .\" bufferpool (shared memory segments) - without writing back to > .\" disk/swap space. This feature is also useful for supporting > -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/ -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
