Import work done under project/nand (@235533) into head.

The NAND Flash environment consists of several distinct components:
  - NAND framework (drivers harness for NAND controllers and NAND chips)
  - NAND simulator (NANDsim)
  - NAND file system (NAND FS)
  - Companion tools and utilities
  - Documentation (manual pages)

This work is still experimental. Please use with caution.

Obtained from: Semihalf
Supported by:  FreeBSD Foundation, Juniper Networks

1 files changed, 1120 insertions, 0 deletions

diff --git a/sys/fs/nandfs/nandfs_subr.c b/sys/fs/nandfs/nandfs_subr.c
new file mode 100644
index 0000000..b485422
--- /dev/null
+++ b/sys/fs/nandfs/nandfs_subr.c
@@ -0,0 +1,1120 @@
+/*-
+ * Copyright (c) 2010-2012 Semihalf
+ * Copyright (c) 2008, 2009 Reinoud Zandijk
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * From: NetBSD: nilfs_subr.c,v 1.4 2009/07/29 17:06:57 reinoud
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/namei.h>
+#include <sys/resourcevar.h>
+#include <sys/kernel.h>
+#include <sys/file.h>
+#include <sys/stat.h>
+#include <sys/buf.h>
+#include <sys/bio.h>
+#include <sys/proc.h>
+#include <sys/mount.h>
+#include <sys/vnode.h>
+#include <sys/signalvar.h>
+#include <sys/malloc.h>
+#include <sys/dirent.h>
+#include <sys/lockf.h>
+#include <sys/libkern.h>
+
+#include <geom/geom.h>
+#include <geom/geom_vfs.h>
+
+#include <vm/vm.h>
+#include <vm/vm_extern.h>
+
+#include <machine/_inttypes.h>
+#include "nandfs_mount.h"
+#include "nandfs.h"
+#include "nandfs_subr.h"
+
+MALLOC_DEFINE(M_NANDFSMNT, "nandfs_mount", "NANDFS mount");;
+MALLOC_DEFINE(M_NANDFSTEMP, "nandfs_tmt", "NANDFS tmp");
+
+uma_zone_t nandfs_node_zone;
+
+void nandfs_bdflush(struct bufobj *bo, struct buf *bp);
+int nandfs_bufsync(struct bufobj *bo, int waitfor);
+
+struct buf_ops buf_ops_nandfs = {
+	.bop_name	=	"buf_ops_nandfs",
+	.bop_write	=	bufwrite,
+	.bop_strategy	=	bufstrategy,
+	.bop_sync	=	nandfs_bufsync,
+	.bop_bdflush	=	nandfs_bdflush,
+};
+
+int
+nandfs_bufsync(struct bufobj *bo, int waitfor)
+{
+	struct vnode *vp;
+	int error = 0;
+
+	vp = bo->__bo_vnode;
+
+	ASSERT_VOP_LOCKED(vp, __func__);
+	error = nandfs_sync_file(vp);
+	if (error)
+		nandfs_warning("%s: cannot flush buffers err:%d\n",
+		    __func__, error);
+
+	return (error);
+}
+
+void
+nandfs_bdflush(bo, bp)
+	struct bufobj *bo;
+	struct buf *bp;
+{
+	struct vnode *vp;
+	int error;
+
+	if (bo->bo_dirty.bv_cnt <= ((dirtybufthresh * 8) / 10))
+		return;
+
+	vp = bp->b_vp;
+	if (NANDFS_SYS_NODE(VTON(vp)->nn_ino))
+		return;
+
+	if (NANDFS_IS_INDIRECT(bp))
+		return;
+
+	error = nandfs_sync_file(vp);
+	if (error)
+		nandfs_warning("%s: cannot flush buffers err:%d\n",
+		    __func__, error);
+}
+
+int
+nandfs_init(struct vfsconf *vfsp)
+{
+
+	nandfs_node_zone = uma_zcreate("nandfs node zone",
+	    sizeof(struct nandfs_node), NULL, NULL, NULL, NULL, 0, 0);
+
+	return (0);
+}
+
+int
+nandfs_uninit(struct vfsconf *vfsp)
+{
+
+	uma_zdestroy(nandfs_node_zone);
+	return (0);
+}
+
+/* Basic calculators */
+uint64_t
+nandfs_get_segnum_of_block(struct nandfs_device *nandfsdev,
+    nandfs_daddr_t blocknr)
+{
+	uint64_t segnum, blks_per_seg;
+
+	MPASS(blocknr >= nandfsdev->nd_fsdata.f_first_data_block);
+
+	blks_per_seg = nandfsdev->nd_fsdata.f_blocks_per_segment;
+
+	segnum = blocknr / blks_per_seg;
+	segnum -= nandfsdev->nd_fsdata.f_first_data_block / blks_per_seg;
+
+	DPRINTF(SYNC, ("%s: returning blocknr %jx -> segnum %jx\n", __func__,
+	    blocknr, segnum));
+
+	return (segnum);
+}
+
+void
+nandfs_get_segment_range(struct nandfs_device *nandfsdev, uint64_t segnum,
+    uint64_t *seg_start, uint64_t *seg_end)
+{
+	uint64_t blks_per_seg;
+
+	blks_per_seg = nandfsdev->nd_fsdata.f_blocks_per_segment;
+	*seg_start = nandfsdev->nd_fsdata.f_first_data_block +
+	    blks_per_seg * segnum;
+	if (seg_end != NULL)
+		*seg_end = *seg_start + blks_per_seg -1;
+}
+
+void nandfs_calc_mdt_consts(struct nandfs_device *nandfsdev,
+    struct nandfs_mdt *mdt, int entry_size)
+{
+	uint32_t blocksize = nandfsdev->nd_blocksize;
+
+	mdt->entries_per_group = blocksize * 8;
+	mdt->entries_per_block = blocksize / entry_size;
+
+	mdt->blocks_per_group =
+	    (mdt->entries_per_group -1) / mdt->entries_per_block + 1 + 1;
+	mdt->groups_per_desc_block =
+	    blocksize / sizeof(struct nandfs_block_group_desc);
+	mdt->blocks_per_desc_block =
+	    mdt->groups_per_desc_block * mdt->blocks_per_group + 1;
+}
+
+int
+nandfs_dev_bread(struct nandfs_device *nandfsdev, nandfs_lbn_t blocknr,
+    struct ucred *cred, int flags, struct buf **bpp)
+{
+	int blk2dev = nandfsdev->nd_blocksize / DEV_BSIZE;
+	int error;
+
+	DPRINTF(BLOCK, ("%s: read from block %jx vp %p\n", __func__,
+	    blocknr * blk2dev, nandfsdev->nd_devvp));
+	error = bread(nandfsdev->nd_devvp, blocknr * blk2dev,
+	    nandfsdev->nd_blocksize, NOCRED, bpp);
+	if (error)
+		nandfs_error("%s: cannot read from device - blk:%jx\n",
+		    __func__, blocknr);
+	return (error);
+}
+
+/* Read on a node */
+int
+nandfs_bread(struct nandfs_node *node, nandfs_lbn_t blocknr,
+    struct ucred *cred, int flags, struct buf **bpp)
+{
+	nandfs_daddr_t vblk;
+	int error;
+
+	DPRINTF(BLOCK, ("%s: vp:%p lbn:%#jx\n", __func__, NTOV(node),
+	    blocknr));
+
+	error = bread(NTOV(node), blocknr, node->nn_nandfsdev->nd_blocksize,
+	    cred, bpp);
+
+	KASSERT(error == 0, ("%s: vp:%p lbn:%#jx err:%d\n", __func__,
+	    NTOV(node), blocknr, error));
+
+	if (!nandfs_vblk_get(*bpp) &&
+	    ((*bpp)->b_flags & B_CACHE) && node->nn_ino != NANDFS_DAT_INO) {
+		nandfs_bmap_lookup(node, blocknr, &vblk);
+		nandfs_vblk_set(*bpp, vblk);
+	}
+	return (error);
+}
+
+int
+nandfs_bread_meta(struct nandfs_node *node, nandfs_lbn_t blocknr,
+    struct ucred *cred, int flags, struct buf **bpp)
+{
+	nandfs_daddr_t vblk;
+	int error;
+
+	DPRINTF(BLOCK, ("%s: vp:%p lbn:%#jx\n", __func__, NTOV(node),
+	    blocknr));
+
+	error = bread(NTOV(node), blocknr, node->nn_nandfsdev->nd_blocksize,
+	    cred, bpp);
+
+	KASSERT(error == 0, ("%s: vp:%p lbn:%#jx err:%d\n", __func__,
+	    NTOV(node), blocknr, error));
+
+	if (!nandfs_vblk_get(*bpp) &&
+	    ((*bpp)->b_flags & B_CACHE) && node->nn_ino != NANDFS_DAT_INO) {
+		nandfs_bmap_lookup(node, blocknr, &vblk);
+		nandfs_vblk_set(*bpp, vblk);
+	}
+
+	return (error);
+}
+
+int
+nandfs_bdestroy(struct nandfs_node *node, nandfs_daddr_t vblk)
+{
+	int error;
+
+	if (!NANDFS_SYS_NODE(node->nn_ino))
+		NANDFS_WRITEASSERT(node->nn_nandfsdev);
+
+	error = nandfs_vblock_end(node->nn_nandfsdev, vblk);
+	if (error) {
+		nandfs_error("%s: ending vblk: %jx failed\n",
+		    __func__, (uintmax_t)vblk);
+		return (error);
+	}
+	node->nn_inode.i_blocks--;
+
+	return (0);
+}
+
+int
+nandfs_bcreate(struct nandfs_node *node, nandfs_lbn_t blocknr,
+    struct ucred *cred, int flags, struct buf **bpp)
+{
+	int error;
+
+	ASSERT_VOP_LOCKED(NTOV(node), __func__);
+	if (!NANDFS_SYS_NODE(node->nn_ino))
+		NANDFS_WRITEASSERT(node->nn_nandfsdev);
+
+	DPRINTF(BLOCK, ("%s: vp:%p lbn:%#jx\n", __func__, NTOV(node),
+	    blocknr));
+
+	*bpp = getblk(NTOV(node), blocknr, node->nn_nandfsdev->nd_blocksize,
+	    0, 0, 0);
+
+	KASSERT((*bpp), ("%s: vp:%p lbn:%#jx\n", __func__,
+	    NTOV(node), blocknr));
+
+	if (*bpp) {
+		vfs_bio_clrbuf(*bpp);
+		(*bpp)->b_blkno = ~(0); /* To avoid VOP_BMAP in bdwrite */
+		error = nandfs_bmap_insert_block(node, blocknr, *bpp);
+		if (error) {
+			nandfs_warning("%s: failed bmap insert node:%p"
+			    " blk:%jx\n", __func__, node, blocknr);
+			brelse(*bpp);
+			return (error);
+		}
+		node->nn_inode.i_blocks++;
+
+		return (0);
+	}
+
+	return (-1);
+}
+
+int
+nandfs_bcreate_meta(struct nandfs_node *node, nandfs_lbn_t blocknr,
+    struct ucred *cred, int flags, struct buf **bpp)
+{
+	struct nandfs_device *fsdev;
+	nandfs_daddr_t vblk;
+	int error;
+
+	ASSERT_VOP_LOCKED(NTOV(node), __func__);
+	NANDFS_WRITEASSERT(node->nn_nandfsdev);
+
+	DPRINTF(BLOCK, ("%s: vp:%p lbn:%#jx\n", __func__, NTOV(node),
+	    blocknr));
+
+	fsdev = node->nn_nandfsdev;
+
+	*bpp = getblk(NTOV(node), blocknr, node->nn_nandfsdev->nd_blocksize,
+	    0, 0, 0);
+
+	KASSERT((*bpp), ("%s: vp:%p lbn:%#jx\n", __func__,
+	    NTOV(node), blocknr));
+
+	memset((*bpp)->b_data, 0, fsdev->nd_blocksize);
+
+	vfs_bio_clrbuf(*bpp);
+	(*bpp)->b_blkno = ~(0); /* To avoid VOP_BMAP in bdwrite */
+
+	nandfs_buf_set(*bpp, NANDFS_VBLK_ASSIGNED);
+
+	if (node->nn_ino != NANDFS_DAT_INO) {
+		error = nandfs_vblock_alloc(fsdev, &vblk);
+		if (error) {
+			nandfs_buf_clear(*bpp, NANDFS_VBLK_ASSIGNED);
+			brelse(*bpp);
+			return (error);
+		}
+	} else
+		vblk = fsdev->nd_fakevblk++;
+
+	nandfs_vblk_set(*bpp, vblk);
+
+	nandfs_bmap_insert_block(node, blocknr, *bpp);
+	return (0);
+}
+
+/* Translate index to a file block number and an entry */
+void
+nandfs_mdt_trans(struct nandfs_mdt *mdt, uint64_t index,
+    nandfs_lbn_t *blocknr, uint32_t *entry_in_block)
+{
+	uint64_t blknr;
+	uint64_t group, group_offset, blocknr_in_group;
+	uint64_t desc_block, desc_offset;
+
+	/* Calculate our offset in the file */
+	group = index / mdt->entries_per_group;
+	group_offset = index % mdt->entries_per_group;
+	desc_block = group / mdt->groups_per_desc_block;
+	desc_offset = group % mdt->groups_per_desc_block;
+	blocknr_in_group = group_offset / mdt->entries_per_block;
+
+	/* To descgroup offset */
+	blknr = 1 + desc_block * mdt->blocks_per_desc_block;
+
+	/* To group offset */
+	blknr += desc_offset * mdt->blocks_per_group;
+
+	/* To actual file block */
+	blknr += 1 + blocknr_in_group;
+
+	*blocknr = blknr;
+	*entry_in_block = group_offset % mdt->entries_per_block;
+}
+
+void
+nandfs_mdt_trans_blk(struct nandfs_mdt *mdt, uint64_t index,
+    uint64_t *desc, uint64_t *bitmap, nandfs_lbn_t *blocknr,
+    uint32_t *entry_in_block)
+{
+	uint64_t blknr;
+	uint64_t group, group_offset, blocknr_in_group;
+	uint64_t desc_block, desc_offset;
+
+	/* Calculate our offset in the file */
+	group = index / mdt->entries_per_group;
+	group_offset = index % mdt->entries_per_group;
+	desc_block = group / mdt->groups_per_desc_block;
+	desc_offset = group % mdt->groups_per_desc_block;
+	blocknr_in_group = group_offset / mdt->entries_per_block;
+
+	/* To descgroup offset */
+	*desc = desc_block * mdt->blocks_per_desc_block;
+	blknr = 1 + desc_block * mdt->blocks_per_desc_block;
+
+	/* To group offset */
+	blknr += desc_offset * mdt->blocks_per_group;
+	*bitmap = blknr;
+
+	/* To actual file block */
+	blknr += 1 + blocknr_in_group;
+
+	*blocknr = blknr;
+	*entry_in_block = group_offset % mdt->entries_per_block;
+
+	DPRINTF(ALLOC,
+	    ("%s: desc_buf: %jx bitmap_buf: %jx entry_buf: %jx entry: %x\n",
+	    __func__, (uintmax_t)*desc, (uintmax_t)*bitmap,
+	    (uintmax_t)*blocknr, *entry_in_block));
+}
+
+int
+nandfs_vtop(struct nandfs_node *node, nandfs_daddr_t vblocknr,
+    nandfs_daddr_t *pblocknr)
+{
+	struct nandfs_node *dat_node;
+	struct nandfs_dat_entry *entry;
+	struct buf *bp;
+	nandfs_lbn_t ldatblknr;
+	uint32_t entry_in_block;
+	int locked, error;
+
+	if (node->nn_ino == NANDFS_DAT_INO || node->nn_ino == NANDFS_GC_INO) {
+		*pblocknr = vblocknr;
+		return (0);
+	}
+
+	/* only translate valid vblocknrs */
+	if (vblocknr == 0)
+		return (0);
+
+	dat_node = node->nn_nandfsdev->nd_dat_node;
+	nandfs_mdt_trans(&node->nn_nandfsdev->nd_dat_mdt, vblocknr, &ldatblknr,
+	    &entry_in_block);
+
+	locked = NANDFS_VOP_ISLOCKED(NTOV(dat_node));
+	if (!locked)
+		VOP_LOCK(NTOV(dat_node), LK_SHARED);
+	error = nandfs_bread(dat_node, ldatblknr, NOCRED, 0, &bp);
+	if (error) {
+		DPRINTF(TRANSLATE, ("vtop: can't read in DAT block %#jx!\n",
+		    (uintmax_t)ldatblknr));
+		brelse(bp);
+		VOP_UNLOCK(NTOV(dat_node), 0);
+		return (error);
+	}
+
+	/* Get our translation */
+	entry = ((struct nandfs_dat_entry *) bp->b_data) + entry_in_block;
+	DPRINTF(TRANSLATE, ("\tentry %p data %p entry_in_block %x\n",
+	    entry, bp->b_data, entry_in_block))
+	DPRINTF(TRANSLATE, ("\tvblk %#jx -> %#jx for cp [%#jx-%#jx]\n",
+	    (uintmax_t)vblocknr, (uintmax_t)entry->de_blocknr,
+	    (uintmax_t)entry->de_start, (uintmax_t)entry->de_end));
+
+	*pblocknr = entry->de_blocknr;
+	brelse(bp);
+	if (!locked)
+		VOP_UNLOCK(NTOV(dat_node), 0);
+
+	MPASS(*pblocknr >= node->nn_nandfsdev->nd_fsdata.f_first_data_block ||
+	    *pblocknr == 0);
+
+	return (0);
+}
+
+int
+nandfs_segsum_valid(struct nandfs_segment_summary *segsum)
+{
+
+	return (segsum->ss_magic == NANDFS_SEGSUM_MAGIC);
+}
+
+int
+nandfs_load_segsum(struct nandfs_device *fsdev, nandfs_daddr_t blocknr,
+    struct nandfs_segment_summary *segsum)
+{
+	struct buf *bp;
+	int error;
+
+	DPRINTF(VOLUMES, ("nandfs: try segsum at block %jx\n",
+	    (uintmax_t)blocknr));
+
+	error = nandfs_dev_bread(fsdev, blocknr, NOCRED, 0, &bp);
+	if (error)
+		return (error);
+
+	memcpy(segsum, bp->b_data, sizeof(struct nandfs_segment_summary));
+	brelse(bp);
+
+	if (!nandfs_segsum_valid(segsum)) {
+		DPRINTF(VOLUMES, ("%s: bad magic pseg:%jx\n", __func__,
+		    blocknr));
+		return (EINVAL);
+	}
+
+	return (error);
+}
+
+static int
+nandfs_load_super_root(struct nandfs_device *nandfsdev,
+    struct nandfs_segment_summary *segsum, uint64_t pseg)
+{
+	struct nandfs_super_root super_root;
+	struct buf *bp;
+	uint64_t blocknr;
+	uint32_t super_root_crc, comp_crc;
+	int off, error;
+
+	/* Check if there is a superroot */
+	if ((segsum->ss_flags & NANDFS_SS_SR) == 0) {
+		DPRINTF(VOLUMES, ("%s: no super root in pseg:%jx\n", __func__,
+		    pseg));
+		return (ENOENT);
+	}
+
+	/* Get our super root, located at the end of the pseg */
+	blocknr = pseg + segsum->ss_nblocks - 1;
+	DPRINTF(VOLUMES, ("%s: try at %#jx\n", __func__, (uintmax_t)blocknr));
+
+	error = nandfs_dev_bread(nandfsdev, blocknr, NOCRED, 0, &bp);
+	if (error)
+		return (error);
+
+	memcpy(&super_root, bp->b_data, sizeof(struct nandfs_super_root));
+	brelse(bp);
+
+	/* Check super root CRC */
+	super_root_crc = super_root.sr_sum;
+	off = sizeof(super_root.sr_sum);
+	comp_crc = crc32((uint8_t *)&super_root + off,
+	    NANDFS_SR_BYTES - off);
+
+	if (super_root_crc != comp_crc) {
+		DPRINTF(VOLUMES, ("%s: invalid crc:%#x [expect:%#x]\n",
+		    __func__, super_root_crc, comp_crc));
+		return (EINVAL);
+	}
+
+	nandfsdev->nd_super_root = super_root;
+	DPRINTF(VOLUMES, ("%s: got valid superroot\n", __func__));
+
+	return (0);
+}
+
+/*
+ * Search for the last super root recorded.
+ */
+int
+nandfs_search_super_root(struct nandfs_device *nandfsdev)
+{
+	struct nandfs_super_block *super;
+	struct nandfs_segment_summary segsum;
+	uint64_t seg_start, seg_end, cno, seq, create, pseg;
+	uint64_t segnum;
+	int error, found;
+
+	error = found = 0;
+
+	/* Search for last super root */
+	pseg = nandfsdev->nd_super.s_last_pseg;
+	segnum = nandfs_get_segnum_of_block(nandfsdev, pseg);
+
+	cno = nandfsdev->nd_super.s_last_cno;
+	create = seq = 0;
+	DPRINTF(VOLUMES, ("%s: start in pseg %#jx\n", __func__,
+	    (uintmax_t)pseg));
+
+	for (;;) {
+		error = nandfs_load_segsum(nandfsdev, pseg, &segsum);
+		if (error)
+			break;
+
+		if (segsum.ss_seq < seq || segsum.ss_create < create)
+			break;
+
+		/* Try to load super root */
+		if (segsum.ss_flags & NANDFS_SS_SR) {
+			error = nandfs_load_super_root(nandfsdev, &segsum, pseg);
+			if (error)
+				break;	/* confused */
+			found = 1;
+
+			super = &nandfsdev->nd_super;
+			nandfsdev->nd_last_segsum = segsum;
+			super->s_last_pseg = pseg;
+			super->s_last_cno = cno++;
+			super->s_last_seq = segsum.ss_seq;
+			super->s_state = NANDFS_VALID_FS;
+			seq = segsum.ss_seq;
+			create = segsum.ss_create;
+		} else {
+			seq = segsum.ss_seq;
+			create = segsum.ss_create;
+		}
+
+		/* Calculate next partial segment location */
+		pseg += segsum.ss_nblocks;
+		DPRINTF(VOLUMES, ("%s: next partial seg is %jx\n", __func__,
+		    (uintmax_t)pseg));
+
+		/* Did we reach the end of the segment? if so, go to the next */
+		nandfs_get_segment_range(nandfsdev, segnum, &seg_start,
+		    &seg_end);
+		if (pseg >= seg_end) {
+			pseg = segsum.ss_next;
+			DPRINTF(VOLUMES,
+			    (" partial seg oor next is %jx[%jx - %jx]\n",
+			    (uintmax_t)pseg, (uintmax_t)seg_start,
+			    (uintmax_t)seg_end));
+		}
+		segnum = nandfs_get_segnum_of_block(nandfsdev, pseg);
+	}
+
+	if (error && !found)
+		return (error);
+
+	return (0);
+}
+
+int
+nandfs_get_node_raw(struct nandfs_device *nandfsdev, struct nandfsmount *nmp,
+    uint64_t ino, struct nandfs_inode *inode, struct nandfs_node **nodep)
+{
+	struct nandfs_node *node;
+	struct vnode *nvp;
+	struct mount *mp;
+	int error;
+
+	*nodep = NULL;
+
+	/* Associate with mountpoint if present */
+	if (nmp) {
+		mp = nmp->nm_vfs_mountp;
+		error = getnewvnode("nandfs", mp, &nandfs_vnodeops, &nvp);
+		if (error) {
+			return (error);
+		}
+	} else {
+		mp = NULL;
+		error = getnewvnode("snandfs", mp, &nandfs_system_vnodeops,
+		    &nvp);
+		if (error) {
+			return (error);
+		}
+	}
+
+	if (mp)
+		NANDFS_WRITELOCK(nandfsdev);
+
+	DPRINTF(IFILE, ("%s: ino: %#jx -> vp: %p\n",
+	    __func__, (uintmax_t)ino, nvp));
+	/* Lock node */
+	lockmgr(nvp->v_vnlock, LK_EXCLUSIVE, NULL);
+
+	if (mp) {
+		error = insmntque(nvp, mp);
+		if (error != 0) {
+			*nodep = NULL;
+			return (error);
+		}
+	}
+
+	node = uma_zalloc(nandfs_node_zone, M_WAITOK | M_ZERO);
+
+	/* Crosslink */
+	node->nn_vnode = nvp;
+	nvp->v_bufobj.bo_ops = &buf_ops_nandfs;
+	node->nn_nmp = nmp;
+	node->nn_nandfsdev = nandfsdev;
+	nvp->v_data = node;
+
+	/* Initiase NANDFS node */
+	node->nn_ino = ino;
+	if (inode != NULL)
+		node->nn_inode = *inode;
+
+	nandfs_vinit(nvp, ino);
+
+	/* Return node */
+	*nodep = node;
+	DPRINTF(IFILE, ("%s: ino:%#jx vp:%p node:%p\n",
+	    __func__, (uintmax_t)ino, nvp, *nodep));
+
+	return (0);
+}
+
+int
+nandfs_get_node(struct nandfsmount *nmp, uint64_t ino,
+    struct nandfs_node **nodep)
+{
+	struct nandfs_device *nandfsdev;
+	struct nandfs_inode inode, *entry;
+	struct vnode *nvp, *vpp;
+	struct thread *td;
+	struct buf *bp;
+	uint64_t ivblocknr;
+	uint32_t entry_in_block;
+	int error;
+
+	/* Look up node in hash table */
+	td = curthread;
+	*nodep = NULL;
+
+	if ((ino < NANDFS_ATIME_INO) && (ino != NANDFS_ROOT_INO)) {
+		printf("nandfs_get_node: system ino %"PRIu64" not in mount "
+		    "point!\n", ino);
+		return (ENOENT);
+	}
+
+	error = vfs_hash_get(nmp->nm_vfs_mountp, ino, LK_EXCLUSIVE, td, &nvp,
+	    NULL, NULL);
+	if (error)
+		return (error);
+
+	if (nvp != NULL) {
+		*nodep = (struct nandfs_node *)nvp->v_data;
+		return (0);
+	}
+
+	/* Look up inode structure in mountpoints ifile */
+	nandfsdev = nmp->nm_nandfsdev;
+	nandfs_mdt_trans(&nandfsdev->nd_ifile_mdt, ino, &ivblocknr,
+	    &entry_in_block);
+
+	VOP_LOCK(NTOV(nmp->nm_ifile_node), LK_SHARED);
+	error = nandfs_bread(nmp->nm_ifile_node, ivblocknr, NOCRED, 0, &bp);
+	if (error) {
+		brelse(bp);
+		VOP_UNLOCK(NTOV(nmp->nm_ifile_node), 0);
+		return (ENOENT);
+	}
+
+	/* Get inode entry */
+	entry = (struct nandfs_inode *) bp->b_data + entry_in_block;
+	memcpy(&inode, entry, sizeof(struct nandfs_inode));
+	brelse(bp);
+	VOP_UNLOCK(NTOV(nmp->nm_ifile_node), 0);
+
+	/* Get node */
+	error = nandfs_get_node_raw(nmp->nm_nandfsdev, nmp, ino, &inode, nodep);
+	if (error) {
+		*nodep = NULL;
+		return (error);
+	}
+
+	nvp = (*nodep)->nn_vnode;
+	error = vfs_hash_insert(nvp, ino, 0, td, &vpp, NULL, NULL);
+	if (error) {
+		*nodep = NULL;
+		return (error);
+	}
+
+	return (error);
+}
+
+void
+nandfs_dispose_node(struct nandfs_node **nodep)
+{
+	struct nandfs_node *node;
+	struct vnode *vp;
+
+	/* Protect against rogue values */
+	node = *nodep;
+	if (!node) {
+		return;
+	}
+	DPRINTF(NODE, ("nandfs_dispose_node: %p\n", *nodep));
+
+	vp = NTOV(node);
+	vp->v_data = NULL;
+
+	/* Free our associated memory */
+	uma_zfree(nandfs_node_zone, node);
+
+	*nodep = NULL;
+}
+
+int
+nandfs_lookup_name_in_dir(struct vnode *dvp, const char *name, int namelen,
+    uint64_t *ino, int *found, uint64_t *off)
+{
+	struct nandfs_node *dir_node = VTON(dvp);
+	struct nandfs_dir_entry	*ndirent;
+	struct buf *bp;
+	uint64_t file_size, diroffset, blkoff;
+	uint64_t blocknr;
+	uint32_t blocksize = dir_node->nn_nandfsdev->nd_blocksize;
+	uint8_t *pos, name_len;
+	int error;
+
+	*found = 0;
+
+	DPRINTF(VNCALL, ("%s: %s file\n", __func__, name));
+	if (dvp->v_type != VDIR) {
+		return (ENOTDIR);
+	}
+
+	/* Get directory filesize */
+	file_size = dir_node->nn_inode.i_size;
+
+	/* Walk the directory */
+	diroffset = 0;
+	blocknr = 0;
+	blkoff = 0;
+	error = nandfs_bread(dir_node, blocknr, NOCRED, 0, &bp);
+	if (error) {
+		brelse(bp);
+		return (EIO);
+	}
+
+	while (diroffset < file_size) {
+		if (blkoff >= blocksize) {
+			blkoff = 0; blocknr++;
+			brelse(bp);
+			error = nandfs_bread(dir_node, blocknr, NOCRED, 0,
+			    &bp);
+			if (error) {
+				brelse(bp);
+				return (EIO);
+			}
+		}
+
+		/* Read in one dirent */
+		pos = (uint8_t *) bp->b_data + blkoff;
+		ndirent = (struct nandfs_dir_entry *) pos;
+		name_len = ndirent->name_len;
+
+		if ((name_len == namelen) &&
+		    (strncmp(name, ndirent->name, name_len) == 0) &&
+		    (ndirent->inode != 0)) {
+			*ino = ndirent->inode;
+			*off = diroffset;
+			DPRINTF(LOOKUP, ("found `%.*s` with ino %"PRIx64"\n",
+			    name_len, ndirent->name, *ino));
+			*found = 1;
+			break;
+		}
+
+		/* Advance */
+		diroffset += ndirent->rec_len;
+		blkoff += ndirent->rec_len;
+	}
+	brelse(bp);
+
+	return (error);
+}
+
+int
+nandfs_get_fsinfo(struct nandfsmount *nmp, struct nandfs_fsinfo *fsinfo)
+{
+	struct nandfs_device *fsdev;
+
+	fsdev = nmp->nm_nandfsdev;
+
+	memcpy(&fsinfo->fs_fsdata, &fsdev->nd_fsdata, sizeof(fsdev->nd_fsdata));
+	memcpy(&fsinfo->fs_super, &fsdev->nd_super, sizeof(fsdev->nd_super));
+	snprintf(fsinfo->fs_dev, sizeof(fsinfo->fs_dev),
+	    "%s", nmp->nm_vfs_mountp->mnt_stat.f_mntfromname);
+
+	return (0);
+}
+
+void
+nandfs_inode_init(struct nandfs_inode *inode, uint16_t mode)
+{
+	struct timespec ts;
+
+	vfs_timestamp(&ts);
+
+	inode->i_blocks = 0;
+	inode->i_size = 0;
+	inode->i_ctime = ts.tv_sec;
+	inode->i_ctime_nsec = ts.tv_nsec;
+	inode->i_mtime = ts.tv_sec;
+	inode->i_mtime_nsec = ts.tv_nsec;
+	inode->i_mode = mode;
+	inode->i_links_count = 1;
+	if (S_ISDIR(mode))
+		inode->i_links_count = 2;
+	inode->i_flags = 0;
+
+	inode->i_special = 0;
+	memset(inode->i_db, 0, sizeof(inode->i_db));
+	memset(inode->i_ib, 0, sizeof(inode->i_ib));
+}
+
+void
+nandfs_inode_destroy(struct nandfs_inode *inode)
+{
+
+	MPASS(inode->i_blocks == 0);
+	bzero(inode, sizeof(*inode));
+}
+
+int
+nandfs_fs_full(struct nandfs_device *nffsdev)
+{
+	uint64_t space, bps;
+
+	bps = nffsdev->nd_fsdata.f_blocks_per_segment;
+	space = (nffsdev->nd_clean_segs - 1) * bps;
+
+	DPRINTF(BUF, ("%s: bufs:%jx space:%jx\n", __func__,
+	    (uintmax_t)nffsdev->nd_dirty_bufs, (uintmax_t)space));
+
+	if (nffsdev->nd_dirty_bufs + (10 * bps) >= space)
+		return (1);
+
+	return (0);
+}
+
+static int
+_nandfs_dirty_buf(struct buf *bp, int dirty_meta, int force)
+{
+	struct nandfs_device *nffsdev;
+	struct nandfs_node *node;
+	uint64_t ino, bps;
+
+	if (NANDFS_ISGATHERED(bp)) {
+		bqrelse(bp);
+		return (0);
+	}
+	if ((bp->b_flags & (B_MANAGED | B_DELWRI)) == (B_MANAGED | B_DELWRI)) {
+		bqrelse(bp);
+		return (0);
+	}
+
+	node = VTON(bp->b_vp);
+	nffsdev = node->nn_nandfsdev;
+	DPRINTF(BUF, ("%s: buf:%p\n", __func__, bp));
+	ino = node->nn_ino;
+
+	if (nandfs_fs_full(nffsdev) && !NANDFS_SYS_NODE(ino) && !force) {
+		brelse(bp);
+		return (ENOSPC);
+	}
+
+	bp->b_flags |= B_MANAGED;
+	bdwrite(bp);
+
+	nandfs_dirty_bufs_increment(nffsdev);
+
+	KASSERT((bp->b_vp), ("vp missing for bp"));
+	KASSERT((nandfs_vblk_get(bp) || ino == NANDFS_DAT_INO),
+	    ("bp vblk is 0"));
+
+	/*
+	 * To maintain consistency of FS we need to force making
+	 * meta buffers dirty, even if free space is low.
+	 */
+	if (dirty_meta && ino != NANDFS_GC_INO)
+		nandfs_bmap_dirty_blocks(VTON(bp->b_vp), bp, 1);
+
+	bps = nffsdev->nd_fsdata.f_blocks_per_segment;
+
+	if (nffsdev->nd_dirty_bufs >= (bps * nandfs_max_dirty_segs)) {
+		mtx_lock(&nffsdev->nd_sync_mtx);
+		if (nffsdev->nd_syncing == 0) {
+			DPRINTF(SYNC, ("%s: wakeup gc\n", __func__));
+			nffsdev->nd_syncing = 1;
+			wakeup(&nffsdev->nd_syncing);
+		}
+		mtx_unlock(&nffsdev->nd_sync_mtx);
+	}
+
+	return (0);
+}
+
+int
+nandfs_dirty_buf(struct buf *bp, int force)
+{
+
+	return (_nandfs_dirty_buf(bp, 1, force));
+}
+
+int
+nandfs_dirty_buf_meta(struct buf *bp, int force)
+{
+
+	return (_nandfs_dirty_buf(bp, 0, force));
+}
+
+void
+nandfs_undirty_buf_fsdev(struct nandfs_device *nffsdev, struct buf *bp)
+{
+
+	BUF_ASSERT_HELD(bp);
+
+	if (bp->b_flags & B_DELWRI) {
+		bp->b_flags &= ~(B_DELWRI|B_MANAGED);
+		nandfs_dirty_bufs_decrement(nffsdev);
+	}
+	/*
+	 * Since it is now being written, we can clear its deferred write flag.
+	 */
+	bp->b_flags &= ~B_DEFERRED;
+
+	brelse(bp);
+}
+
+void
+nandfs_undirty_buf(struct buf *bp)
+{
+	struct nandfs_node *node;
+
+	node = VTON(bp->b_vp);
+
+	nandfs_undirty_buf_fsdev(node->nn_nandfsdev, bp);
+}
+
+void
+nandfs_vblk_set(struct buf *bp, nandfs_daddr_t blocknr)
+{
+
+	nandfs_daddr_t *vblk = (nandfs_daddr_t *)(&bp->b_fsprivate1);
+	*vblk = blocknr;
+}
+
+nandfs_daddr_t
+nandfs_vblk_get(struct buf *bp)
+{
+
+	nandfs_daddr_t *vblk = (nandfs_daddr_t *)(&bp->b_fsprivate1);
+	return (*vblk);
+}
+
+void
+nandfs_buf_set(struct buf *bp, uint32_t bits)
+{
+	uintptr_t flags;
+
+	flags = (uintptr_t)bp->b_fsprivate3;
+	flags |= (uintptr_t)bits;
+	bp->b_fsprivate3 = (void *)flags;
+}
+
+void
+nandfs_buf_clear(struct buf *bp, uint32_t bits)
+{
+	uintptr_t flags;
+
+	flags = (uintptr_t)bp->b_fsprivate3;
+	flags &= ~(uintptr_t)bits;
+	bp->b_fsprivate3 = (void *)flags;
+}
+
+int
+nandfs_buf_check(struct buf *bp, uint32_t bits)
+{
+	uintptr_t flags;
+
+	flags = (uintptr_t)bp->b_fsprivate3;
+	if (flags & bits)
+		return (1);
+	return (0);
+}
+
+int
+nandfs_erase(struct nandfs_device *fsdev, off_t offset, size_t size)
+{
+	struct buf *bp;
+	int read_size, error, i;
+
+	DPRINTF(BLOCK, ("%s: performing erase at offset %jx size %zx\n",
+	    __func__, offset, size));
+
+	MPASS(size % fsdev->nd_erasesize == 0);
+
+	if (fsdev->nd_is_nand) {
+		error = g_delete_data(fsdev->nd_gconsumer, offset, size);
+		return (error);
+	}
+
+	if (size > MAXBSIZE)
+		read_size = MAXBSIZE;
+	else
+		read_size = size;
+
+	error = 0;
+	for (i = 0; i < size / MAXBSIZE; i++) {
+		error = bread(fsdev->nd_devvp, btodb(offset + i * read_size),
+		    read_size, NOCRED, &bp);
+		if (error) {
+			brelse(bp);
+			return (error);
+		}
+		memset(bp->b_data, 0xff, read_size);
+		error = bwrite(bp);
+		if (error) {
+			nandfs_error("%s: err:%d from bwrite\n",
+			    __func__, error);
+			return (error);
+		}
+	}
+
+	return (error);
+}
+
+int
+nandfs_vop_islocked(struct vnode *vp)
+{
+	int islocked;
+
+	islocked = VOP_ISLOCKED(vp);
+	return (islocked == LK_EXCLUSIVE || islocked == LK_SHARED);
+}
+
+nandfs_daddr_t
+nandfs_block_to_dblock(struct nandfs_device *fsdev, nandfs_lbn_t block)
+{
+
+	return (btodb(block * fsdev->nd_blocksize));
+}