pNFS: Force a retry of LAYOUTGET if the stateid doesn't match our cache

If the server sends us a completely new stateid, and the client thinks
it already holds a layout, then force a retry of the LAYOUTGET after
invalidating the existing layout in order to avoid corruption due to
races.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
This commit is contained in:
Trond Myklebust 2016-11-23 12:36:04 -05:00
parent ae5a459d5f
commit 9888d837f3

View File

@ -1844,7 +1844,10 @@ pnfs_layout_process(struct nfs4_layoutget *lgp)
goto out_forget;
}
if (nfs4_stateid_match_other(&lo->plh_stateid, &res->stateid)) {
if (!pnfs_layout_is_valid(lo)) {
/* We have a completely new layout */
pnfs_set_layout_stateid(lo, &res->stateid, true);
} else if (nfs4_stateid_match_other(&lo->plh_stateid, &res->stateid)) {
/* existing state ID, make sure the sequence number matches. */
if (pnfs_layout_stateid_blocked(lo, &res->stateid)) {
dprintk("%s forget reply due to sequence\n", __func__);
@ -1854,12 +1857,10 @@ pnfs_layout_process(struct nfs4_layoutget *lgp)
} else {
/*
* We got an entirely new state ID. Mark all segments for the
* inode invalid, and don't bother validating the stateid
* sequence number.
* inode invalid, and retry the layoutget
*/
pnfs_mark_layout_stateid_invalid(lo, &free_me);
pnfs_set_layout_stateid(lo, &res->stateid, true);
goto out_forget;
}
pnfs_get_lseg(lseg);