Add b_bufobj to struct buf which eventually will eliminate the need for b_vp.

Initialize b_bufobj for all buffers.

Make incore() and gbincore() take a bufobj instead of a vnode.

Make inmem() local to vfs_bio.c

Change a lot of VI_[UN]LOCK(bp->b_vp) to BO_[UN]LOCK(bp->b_bufobj)
also VI_MTX() to BO_MTX(),

Make buf_vlist_add() take a bufobj instead of a vnode.

Eliminate other uses of bp->b_vp where bp->b_bufobj will do.

Various minor polishing: remove "register", turn panic into KASSERT,
use new function declarations, TAILQ_FOREACH_SAFE() etc.

4 files changed, 10 insertions, 12 deletions

diff --git a/sys/nfsclient/nfs_bio.c b/sys/nfsclient/nfs_bio.c
index 5364af4..7148834 100644
--- a/sys/nfsclient/nfs_bio.c
+++ b/sys/nfsclient/nfs_bio.c
@@ -455,7 +455,7 @@ nfs_bioread(struct vnode *vp, struct uio *uio, int ioflag, struct ucred *cred)
 		    for (nra = 0; nra < nmp->nm_readahead && nra < seqcount &&
 			(off_t)(lbn + 1 + nra) * biosize < np->n_size; nra++) {
 			rabn = lbn + 1 + nra;
-			if (incore(vp, rabn) == NULL) {
+			if (incore(&vp->v_bufobj, rabn) == NULL) {
 			    rabp = nfs_getcacheblk(vp, rabn, biosize, td);
 			    if (!rabp) {
 				error = nfs_sigintr(nmp, NULL, td);
@@ -651,7 +651,7 @@ again:
 		    (bp->b_flags & B_INVAL) == 0 &&
 		    (np->n_direofoffset == 0 ||
 		    (lbn + 1) * NFS_DIRBLKSIZ < np->n_direofoffset) &&
-		    incore(vp, lbn + 1) == NULL) {
+		    incore(&vp->v_bufobj, lbn + 1) == NULL) {
 			rabp = nfs_getcacheblk(vp, lbn + 1, NFS_DIRBLKSIZ, td);
 			if (rabp) {
 			    if ((rabp->b_flags & (B_CACHE|B_DELWRI)) == 0) {
diff --git a/sys/nfsclient/nfs_subs.c b/sys/nfsclient/nfs_subs.c
index f9869c2..aa1887a 100644
--- a/sys/nfsclient/nfs_subs.c
+++ b/sys/nfsclient/nfs_subs.c
@@ -813,8 +813,7 @@ nfs_clearcommit(struct mount *mp)
 			continue;
 		}
 		MNT_IUNLOCK(mp);
-		for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) {
-			nbp = TAILQ_NEXT(bp, b_bobufs);
+		TAILQ_FOREACH_SAFE(bp, &vp->v_bufobj.bo_dirty.bv_hd, b_bobufs, nbp) {
 			if (BUF_REFCNT(bp) == 0 &&
 			    (bp->b_flags & (B_DELWRI | B_NEEDCOMMIT))
 				== (B_DELWRI | B_NEEDCOMMIT))
diff --git a/sys/nfsclient/nfs_vfsops.c b/sys/nfsclient/nfs_vfsops.c
index 8740749..6cbe859 100644
--- a/sys/nfsclient/nfs_vfsops.c
+++ b/sys/nfsclient/nfs_vfsops.c
@@ -954,7 +954,8 @@ loop:
 	MNT_VNODE_FOREACH(vp, mp, nvp) {
 		VI_LOCK(vp);
 		MNT_IUNLOCK(mp);
-		if (VOP_ISLOCKED(vp, NULL) || TAILQ_EMPTY(&vp->v_dirtyblkhd) ||
+		if (VOP_ISLOCKED(vp, NULL) ||
+		    vp->v_bufobj.bo_dirty.bv_cnt == 0 ||
 		    waitfor == MNT_LAZY) {
 			VI_UNLOCK(vp);
 			MNT_ILOCK(mp);
diff --git a/sys/nfsclient/nfs_vnops.c b/sys/nfsclient/nfs_vnops.c
index efc2e61..d664573 100644
--- a/sys/nfsclient/nfs_vnops.c
+++ b/sys/nfsclient/nfs_vnops.c
@@ -2618,8 +2618,7 @@ again:
 		 */
 		bveccount = 0;
 		VI_LOCK(vp);
-		for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) {
-			nbp = TAILQ_NEXT(bp, b_bobufs);
+		TAILQ_FOREACH_SAFE(bp, &vp->v_bufobj.bo_dirty.bv_hd, b_bobufs, nbp) {
 			if (BUF_REFCNT(bp) == 0 &&
 			    (bp->b_flags & (B_DELWRI | B_NEEDCOMMIT))
 				== (B_DELWRI | B_NEEDCOMMIT))
@@ -2650,7 +2649,7 @@ again:
 			bvec = bvec_on_stack;
 			bvecsize = NFS_COMMITBVECSIZ;
 		}
-		for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) {
+		TAILQ_FOREACH_SAFE(bp, &vp->v_bufobj.bo_dirty.bv_hd, b_bobufs, nbp) {
 			if (bvecpos >= bvecsize)
 				break;
 			if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT, NULL)) {
@@ -2778,8 +2777,7 @@ again:
 loop:
 	s = splbio();
 	VI_LOCK(vp);
-	for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) {
-		nbp = TAILQ_NEXT(bp, b_bobufs);
+	TAILQ_FOREACH_SAFE(bp, &vp->v_bufobj.bo_dirty.bv_hd, b_bobufs, nbp) {
 		if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT, NULL)) {
 			if (waitfor != MNT_WAIT || passone)
 				continue;
@@ -2838,7 +2836,7 @@ loop:
 			    VI_LOCK(vp);
 			}
 		}
-		if (!TAILQ_EMPTY(&vp->v_dirtyblkhd) && commit) {
+		if (vp->v_bufobj.bo_dirty.bv_cnt != 0 && commit) {
 			VI_UNLOCK(vp);
 			goto loop;
 		}
@@ -2920,7 +2918,7 @@ nfs_writebp(struct buf *bp, int force __unused, struct thread *td)
 	bp->b_ioflags &= ~BIO_ERROR;
 	bp->b_iocmd = BIO_WRITE;
 
-	bufobj_wref(&bp->b_vp->v_bufobj);
+	bufobj_wref(bp->b_bufobj);
 	curthread->td_proc->p_stats->p_ru.ru_oublock++;
 	splx(s);