On Wed, Nov 23, 2011 at 10:53 AM, Cong Wang <amwang@xxxxxxxxxx> wrote: > Systemd needs tmpfs to support fallocate [1], to be able > to safely use mmap(), regarding SIGBUS, on files on the > /dev/shm filesystem. The glibc fallback loop for -ENOSYS > on fallocate is just ugly. > > This patch adds fallocate support to tmpfs, and as we > already have shmem_truncate_range(), it is also easy to > add FALLOC_FL_PUNCH_HOLE support too. > > 1. http://lkml.org/lkml/2011/10/20/275 > > V2->V3: > a) Read i_size directly after holding i_mutex; > b) Call page_cache_release() too after shmem_getpage(); > c) Undo previous changes when -ENOSPC. > > Cc: Pekka Enberg <penberg@xxxxxxxxxx> > Cc: Christoph Hellwig <hch@xxxxxx> > Cc: Hugh Dickins <hughd@xxxxxxxxxx> > Cc: Dave Hansen <dave@xxxxxxxxxxxxxxxxxx> > Cc: Lennart Poettering <lennart@xxxxxxxxxxxxxx> > Cc: Kay Sievers <kay.sievers@xxxxxxxx> > Cc: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> > Signed-off-by: WANG Cong <amwang@xxxxxxxxxx> Looks reasonable to me. Acked-by: Pekka Enberg <penberg@xxxxxxxxxx> Did someone actually test this with systemd? -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>