From 6602376e3e9e6d9f4f695475569322b61ccc2411 Mon Sep 17 00:00:00 2001 From: Jeff Darcy Date: Thu, 31 Mar 2016 17:15:37 -0400 Subject: dht: add "nuke" functionality for efficient server-side deletion This turns a special xattr into an rmdir with flags set. When that hits the posix translator on the server side, that causes the file/directory to be moved into the special "landfill" directory. From there, the posix janitor thread will take care of deleting it entirely on the server side - traversing it recursively if necessary. A couple of secondary issues were fixed to make this effective. * FUSE now ensures that setxattr values are NUL terminated. * The janitor thread now gets woken up immediately when something is placed in 'landfill' instead of only when file descriptors need to be closed. * The default landfill-emptying interval was reduced to 10s. To use the feature, issue a setxattr something like this: setfattr -n glusterfs.dht.nuke -v "" /mnt/glusterfs/vol/some_dir The value doesn't actually matter; the mere receipt of a request with this key is sufficient. Some day it might be useful to allow setting a required value as a sort of password, so that only those who know it can access the underlying special functionality. Change-Id: I8a343c2cdb40a76d5a06c707191fb67babb8514f Signed-off-by: Jeff Darcy Reviewed-on: http://review.gluster.org/13878 Smoke: Gluster Build System NetBSD-regression: NetBSD Build System CentOS-regression: Gluster Build System Reviewed-by: Raghavendra G --- xlators/mount/fuse/src/fuse-bridge.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'xlators/mount') diff --git a/xlators/mount/fuse/src/fuse-bridge.c b/xlators/mount/fuse/src/fuse-bridge.c index c6c38f3145b..aca1b3d14fd 100644 --- a/xlators/mount/fuse/src/fuse-bridge.c +++ b/xlators/mount/fuse/src/fuse-bridge.c @@ -3292,7 +3292,14 @@ fuse_setxattr (xlator_t *this, fuse_in_header_t *finh, void *msg) } if (fsi->size > 0) { - dict_value = memdup (value, fsi->size); + /* + * Many translators expect setxattr values to be strings, but + * neither dict_get_str nor data_to_str do any checking or + * fixups to make sure that's the case. To avoid nasty + * surprises, allocate an extra byte and add a NUL here. + */ + dict_value = memdup (value, fsi->size+1); + dict_value[fsi->size] = '\0'; } dict_set (state->xattr, newkey, data_from_dynptr ((void *)dict_value, fsi->size)); -- cgit