--- sys/dev/md/md.c	2006/12/14 11:36:47
+++ sys/dev/md/md.c	2007/02/03 00:33:55
@@ -609,15 +609,14 @@
 	for (i = bp->bio_offset / PAGE_SIZE; i <= lastp; i++) {
 		len = ((i == lastp) ? lastend : PAGE_SIZE) - offs;
 
-		m = vm_page_grab(sc->object, i,
-		    VM_ALLOC_NORMAL|VM_ALLOC_RETRY);
+		m = vm_page_grab(sc->object, i, VM_ALLOC_NORMAL|VM_ALLOC_RETRY);
 		VM_OBJECT_UNLOCK(sc->object);
 		sched_pin();
 		sf = sf_buf_alloc(m, SFB_CPUPRIVATE);
 		VM_OBJECT_LOCK(sc->object);
-		if (bp->bio_cmd == BIO_READ) {
-			if (m->valid != VM_PAGE_BITS_ALL)
-				rv = vm_pager_get_pages(sc->object, &m, 1, 0);
+		if ((bp->bio_cmd == BIO_READ || len != PAGE_SIZE) &&
+		    m->valid != VM_PAGE_BITS_ALL) {
+			rv = vm_pager_get_pages(sc->object, &m, 1, 0);
 			if (rv == VM_PAGER_ERROR) {
 				sf_buf_free(sf);
 				sched_unpin();
@@ -626,44 +625,47 @@
 				vm_page_unlock_queues();
 				break;
 			}
+		}
+		switch (bp->bio_cmd) {
+		case BIO_READ:
 			bcopy((void *)(sf_buf_kva(sf) + offs), p, len);
-		} else if (bp->bio_cmd == BIO_WRITE) {
-			if (len != PAGE_SIZE && m->valid != VM_PAGE_BITS_ALL)
-				rv = vm_pager_get_pages(sc->object, &m, 1, 0);
-			if (rv == VM_PAGER_ERROR) {
-				sf_buf_free(sf);
-				sched_unpin();
-				vm_page_lock_queues();
-				vm_page_wakeup(m);
-				vm_page_unlock_queues();
-				break;
-			}
+			break;
+		case BIO_WRITE:
 			bcopy(p, (void *)(sf_buf_kva(sf) + offs), len);
 			m->valid = VM_PAGE_BITS_ALL;
-#if 0
-		} else if (bp->bio_cmd == BIO_DELETE) {
-			if (len != PAGE_SIZE && m->valid != VM_PAGE_BITS_ALL)
-				rv = vm_pager_get_pages(sc->object, &m, 1, 0);
-			if (rv == VM_PAGER_ERROR) {
-				sf_buf_free(sf);
-				sched_unpin();
-				vm_page_lock_queues();
-				vm_page_wakeup(m);
-				vm_page_unlock_queues();
-				break;
-			}
+			break;
+		case BIO_DELETE:
 			bzero((void *)(sf_buf_kva(sf) + offs), len);
-			vm_page_dirty(m);
-			m->valid = VM_PAGE_BITS_ALL;
-#endif
+			break;
 		}
 		sf_buf_free(sf);
 		sched_unpin();
 		vm_page_lock_queues();
-		vm_page_wakeup(m);
-		vm_page_activate(m);
-		if (bp->bio_cmd == BIO_WRITE)
+		switch (bp->bio_cmd) {
+		case BIO_READ:
+			vm_page_wakeup(m);
+			vm_page_activate(m);
+			break;
+		case BIO_WRITE:
+			vm_page_wakeup(m);
+			vm_page_activate(m);
 			vm_page_dirty(m);
+			break;
+		case BIO_DELETE:
+#if 0
+			vm_page_set_invalid(m, offs, len);
+			if (m->valid != 0) {
+				vm_page_wakeup(m);
+				vm_page_activate(m);
+			} else {
+#endif
+				vm_pager_page_unswapped(m);
+				vm_page_free(m);
+#if 0
+			}
+#endif
+			break;
+		}
 		vm_page_unlock_queues();
 
 		/* Actions on further pages start at offset 0 */
--- sys/geom/geom.h	2006/10/31 21:16:32
+++ sys/geom/geom.h	2007/02/01 08:46:18
@@ -274,6 +274,7 @@
 struct bio *g_alloc_bio(void);
 void * g_read_data(struct g_consumer *cp, off_t offset, off_t length, int *error);
 int g_write_data(struct g_consumer *cp, off_t offset, void *ptr, off_t length);
+int g_delete_data(struct g_consumer *cp, off_t offset, off_t length);
 void g_print_bio(struct bio *bp);
 
 /* geom_kern.c / geom_kernsim.c */
@@ -286,6 +287,10 @@
 	off_t		offset;
 	off_t		length;
 };
+struct g_delete {
+	off_t		offset;
+	off_t		length;
+};
 
 MALLOC_DECLARE(M_GEOM);
 
--- sys/geom/geom_dev.c	2006/06/18 22:01:39
+++ sys/geom/geom_dev.c	2007/02/01 09:02:09
@@ -253,6 +253,7 @@
 	struct g_geom *gp;
 	struct g_consumer *cp;
 	struct g_kerneldump kd;
+	struct g_delete *del;
 	int i, error;
 	u_int u;
 
@@ -302,6 +303,19 @@
 		if (!error)
 			dev->si_flags |= SI_DUMPDEV;
 		break;
+	case DIOCGFLUSH:
+		error = g_io_flush(cp);
+		break;
+	case DIOCGDELETE:
+		del = (struct g_delete *)data;
+		if ((del->offset % cp->provider->sectorsize) != 0 ||
+		    (del->length % cp->provider->sectorsize) != 0 ||
+		     del->length <= 0 || del->length > MAXPHYS) {
+			error = EINVAL;
+			break;
+		}
+		error = g_delete_data(cp, del->offset, del->length);
+		break;
 
 	default:
 		if (cp->provider->geom->ioctl != NULL) {
--- sys/geom/geom_io.c	2007/01/28 23:41:05
+++ sys/geom/geom_io.c	2007/02/01 08:40:42
@@ -646,6 +646,28 @@
 	return (error);
 }
 
+int
+g_delete_data(struct g_consumer *cp, off_t offset, off_t length)
+{
+	struct bio *bp;
+	int error;
+
+	KASSERT(length > 0 && length >= cp->provider->sectorsize &&
+	    length <= MAXPHYS, ("g_delete_data(): invalid length %jd",
+	    (intmax_t)length));
+
+	bp = g_alloc_bio();
+	bp->bio_cmd = BIO_DELETE;
+	bp->bio_done = NULL;
+	bp->bio_offset = offset;
+	bp->bio_length = length;
+	bp->bio_data = NULL;
+	g_io_request(bp, cp);
+	error = biowait(bp, "gdelete");
+	g_destroy_bio(bp);
+	return (error);
+}
+
 void
 g_print_bio(struct bio *bp)
 {
--- sys/sys/disk.h	2006/03/11 10:35:20
+++ sys/sys/disk.h	2007/02/01 10:36:16
@@ -57,7 +57,7 @@
 	 * Enable/Disable (the argument is boolean) the device for kernel
 	 * core dumps.
 	 */
-	
+
 #define DIOCGFRONTSTUFF _IOR('d', 134, off_t)
 	/*-
 	 * Many disk formats have some amount of space reserved at the
@@ -66,4 +66,18 @@
 	 * which may apply to the device.
 	 */
 
+#define DIOCGFLUSH _IO('d', 135)		/* Flush write cache */
+	/*-
+	 * Flush write cache of the device.
+	 */
+
+struct g_offlen {
+	off_t	offset;
+	off_t	length;
+};
+#define DIOCGDELETE _IOW('d', 136, struct g_offlen) /* Delete data */
+	/*-
+	 * Mark data on the device as unused.
+	 */
+
 #endif /* _SYS_DISK_H_ */
--- sys/ufs/ffs/ffs_alloc.c	2007/01/20 12:02:48
+++ sys/ufs/ffs/ffs_alloc.c	2007/01/28 04:13:44
@@ -79,6 +79,8 @@
 #include <sys/sysctl.h>
 #include <sys/syslog.h>
 
+#include <geom/geom.h>
+
 #include <ufs/ufs/extattr.h>
 #include <ufs/ufs/quota.h>
 #include <ufs/ufs/inode.h>
@@ -1809,7 +1811,7 @@
 	struct buf *bp;
 	ufs1_daddr_t fragno, cgbno;
 	ufs2_daddr_t cgblkno;
-	int i, cg, blk, frags, bbase;
+	int i, cg, blk, frags, bbase, error;
 	u_int8_t *blksfree;
 	struct cdev *dev;
 
@@ -1920,6 +1922,9 @@
 	ACTIVECLEAR(fs, cg);
 	UFS_UNLOCK(ump);
 	bdwrite(bp);
+	error = g_delete_data(ump->um_cp, bno * fs->fs_fsize, size);
+	if (error != 0 && error != EOPNOTSUPP)
+		ffs_fserr(fs, inum, "cannot delete data");
 }
 
 #ifdef DIAGNOSTIC