Index: vm/vm_pager.c
===================================================================
--- vm/vm_pager.c	(revision 255404)
+++ vm/vm_pager.c	(working copy)
@@ -75,6 +75,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/ucred.h>
 #include <sys/malloc.h>
 #include <sys/rwlock.h>
+#include <sys/vmem.h>
 
 #include <vm/vm.h>
 #include <vm/vm_param.h>
@@ -176,9 +177,8 @@ static const int npagers = sizeof(pagertab) / size
  * (MAXPHYS == 64k) if you want to get the most efficiency.
  */
 struct mtx_padalign pbuf_mtx;
-static TAILQ_HEAD(swqueue, buf) bswlist;
-static int bswneeded;
 vm_offset_t swapbkva;		/* swap buffers kva */
+static vmem_t	*pbuf_vmem;
 
 void
 vm_pager_init()
@@ -185,7 +185,6 @@ vm_pager_init()
 {
 	struct pagerops **pgops;
 
-	TAILQ_INIT(&bswlist);
 	/*
 	 * Initialize known pagers
 	 */
@@ -206,7 +205,6 @@ vm_pager_bufferinit()
 	 * Now set up swap and physical I/O buffer headers.
 	 */
 	for (i = 0; i < nswbuf; i++, bp++) {
-		TAILQ_INSERT_HEAD(&bswlist, bp, b_freelist);
 		BUF_LOCKINIT(bp);
 		LIST_INIT(&bp->b_dep);
 		bp->b_rcred = bp->b_wcred = NOCRED;
@@ -215,6 +213,8 @@ vm_pager_bufferinit()
 
 	cluster_pbuf_freecnt = nswbuf / 2;
 	vnode_pbuf_freecnt = nswbuf / 2 + 1;
+
+	pbuf_vmem = vmem_create("pbuf", 1, nswbuf, 1, 1, M_WAITOK | M_FIRSTFIT);
 }
 
 /*
@@ -327,31 +327,22 @@ struct buf *
 getpbuf(int *pfreecnt)
 {
 	struct buf *bp;
+	vmem_addr_t i;
 
-	mtx_lock(&pbuf_mtx);
-
-	for (;;) {
-		if (pfreecnt) {
-			while (*pfreecnt == 0) {
-				msleep(pfreecnt, &pbuf_mtx, PVM, "wswbuf0", 0);
-			}
+	if (pfreecnt) {
+		mtx_lock(&pbuf_mtx);
+		while (*pfreecnt == 0) {
+			msleep(pfreecnt, &pbuf_mtx, PVM, "wswbuf0", 0);
 		}
-
-		/* get a bp from the swap buffer header pool */
-		if ((bp = TAILQ_FIRST(&bswlist)) != NULL)
-			break;
-
-		bswneeded = 1;
-		msleep(&bswneeded, &pbuf_mtx, PVM, "wswbuf1", 0);
-		/* loop in case someone else grabbed one */
+		--*pfreecnt;
+		mtx_unlock(&pbuf_mtx);
 	}
-	TAILQ_REMOVE(&bswlist, bp, b_freelist);
-	if (pfreecnt)
-		--*pfreecnt;
-	mtx_unlock(&pbuf_mtx);
 
+	/* get a bp from the swap buffer header pool */
+	vmem_alloc(pbuf_vmem, 1, M_WAITOK | M_BESTFIT, &i);
+	bp = &swbuf[i - 1];
 	initpbuf(bp);
-	return bp;
+	return (bp);
 }
 
 /*
@@ -364,21 +355,22 @@ struct buf *
 trypbuf(int *pfreecnt)
 {
 	struct buf *bp;
+	vmem_addr_t i;
 
 	mtx_lock(&pbuf_mtx);
-	if (*pfreecnt == 0 || (bp = TAILQ_FIRST(&bswlist)) == NULL) {
+	if (*pfreecnt == 0) {
 		mtx_unlock(&pbuf_mtx);
+		return (NULL);
+	}
+	if (vmem_alloc(pbuf_vmem, 1, M_NOWAIT | M_BESTFIT, &i) != 0) {
+		mtx_unlock(&pbuf_mtx);
 		return NULL;
 	}
-	TAILQ_REMOVE(&bswlist, bp, b_freelist);
-
 	--*pfreecnt;
-
 	mtx_unlock(&pbuf_mtx);
-
+	bp = &swbuf[i - 1];
 	initpbuf(bp);
-
-	return bp;
+	return (bp);
 }
 
 /*
@@ -405,18 +397,13 @@ relpbuf(struct buf *bp, int *pfreecnt)
 
 	BUF_UNLOCK(bp);
 
-	mtx_lock(&pbuf_mtx);
-	TAILQ_INSERT_HEAD(&bswlist, bp, b_freelist);
-
-	if (bswneeded) {
-		bswneeded = 0;
-		wakeup(&bswneeded);
-	}
+	vmem_free(pbuf_vmem, bp - swbuf + 1, 1);
 	if (pfreecnt) {
+		mtx_lock(&pbuf_mtx);
 		if (++*pfreecnt == 1)
 			wakeup(pfreecnt);
+		mtx_unlock(&pbuf_mtx);
 	}
-	mtx_unlock(&pbuf_mtx);
 }
 
 /*