Author: kib Date: Sun Aug 16 21:05:56 2020 New Revision: 364288 URL: https://svnweb.freebsd.org/changeset/base/364288
Log: VMIO reads: enable for nullfs upper vnode if the lower vnode supports it. Reviewed by: markj Tested by: pho Sponsored by: The FreeBSD Foundation Differential revision: https://reviews.freebsd.org/D25968 Modified: head/sys/fs/nullfs/null_subr.c head/sys/fs/nullfs/null_vnops.c Modified: head/sys/fs/nullfs/null_subr.c ============================================================================== --- head/sys/fs/nullfs/null_subr.c Sun Aug 16 21:02:45 2020 (r364287) +++ head/sys/fs/nullfs/null_subr.c Sun Aug 16 21:05:56 2020 (r364288) @@ -259,12 +259,33 @@ null_nodeget(mp, lowervp, vpp) vp->v_vflag |= VV_ROOT; /* + * We might miss the case where lower vnode sets VIRF_PGREAD + * some time after construction, which is typical case. + * null_open rechecks. + */ + if ((lowervp->v_irflag & VIRF_PGREAD) != 0) { + MPASS(lowervp->v_object != NULL); + if ((vp->v_irflag & VIRF_PGREAD) == 0) { + if (vp->v_object == NULL) + vp->v_object = lowervp->v_object; + else + MPASS(vp->v_object == lowervp->v_object); + VI_LOCK(vp); + vp->v_irflag |= VIRF_PGREAD; + VI_UNLOCK(vp); + } else { + MPASS(vp->v_object != NULL); + } + } + + /* * Atomically insert our new node into the hash or vget existing * if someone else has beaten us to it. */ *vpp = null_hashins(mp, xp); if (*vpp != NULL) { vrele(lowervp); + vp->v_object = NULL; /* in case VIRF_PGREAD set it */ null_destroy_proto(vp, xp); return (0); } Modified: head/sys/fs/nullfs/null_vnops.c ============================================================================== --- head/sys/fs/nullfs/null_vnops.c Sun Aug 16 21:02:45 2020 (r364287) +++ head/sys/fs/nullfs/null_vnops.c Sun Aug 16 21:05:56 2020 (r364288) @@ -439,8 +439,17 @@ null_open(struct vop_open_args *ap) vp = ap->a_vp; ldvp = NULLVPTOLOWERVP(vp); retval = null_bypass(&ap->a_gen); - if (retval == 0) + if (retval == 0) { vp->v_object = ldvp->v_object; + if ((ldvp->v_irflag & VIRF_PGREAD) != 0) { + MPASS(vp->v_object != NULL); + if ((vp->v_irflag & VIRF_PGREAD) == 0) { + VI_LOCK(vp); + vp->v_irflag |= VIRF_PGREAD; + VI_UNLOCK(vp); + } + } + } return (retval); } _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
