13 files changed, 368 insertions, 364 deletions

diff --git a/fs/nilfs2/bmap.c b/fs/nilfs2/bmap.c
index 24638e059bf..064279e33bb 100644
--- a/fs/nilfs2/bmap.c
+++ b/fs/nilfs2/bmap.c
@@ -688,6 +688,8 @@ static const struct nilfs_bmap_ptr_operations nilfs_bmap_ptr_ops_gc = {
 	.bpop_translate		=	NULL,
 };
 
+static struct lock_class_key nilfs_bmap_dat_lock_key;
+
 /**
  * nilfs_bmap_read - read a bmap from an inode
  * @bmap: bmap
@@ -715,6 +717,7 @@ int nilfs_bmap_read(struct nilfs_bmap *bmap, struct nilfs_inode *raw_inode)
 		bmap->b_pops = &nilfs_bmap_ptr_ops_p;
 		bmap->b_last_allocated_key = 0;	/* XXX: use macro */
 		bmap->b_last_allocated_ptr = NILFS_BMAP_NEW_PTR_INIT;
+		lockdep_set_class(&bmap->b_sem, &nilfs_bmap_dat_lock_key);
 		break;
 	case NILFS_CPFILE_INO:
 	case NILFS_SUFILE_INO:
@@ -772,6 +775,7 @@ void nilfs_bmap_init_gcdat(struct nilfs_bmap *gcbmap, struct nilfs_bmap *bmap)
 {
 	memcpy(gcbmap, bmap, sizeof(union nilfs_bmap_union));
 	init_rwsem(&gcbmap->b_sem);
+	lockdep_set_class(&bmap->b_sem, &nilfs_bmap_dat_lock_key);
 	gcbmap->b_inode = &NILFS_BMAP_I(gcbmap)->vfs_inode;
 }
 
@@ -779,5 +783,6 @@ void nilfs_bmap_commit_gcdat(struct nilfs_bmap *gcbmap, struct nilfs_bmap *bmap)
 {
 	memcpy(bmap, gcbmap, sizeof(union nilfs_bmap_union));
 	init_rwsem(&bmap->b_sem);
+	lockdep_set_class(&bmap->b_sem, &nilfs_bmap_dat_lock_key);
 	bmap->b_inode = &NILFS_BMAP_I(bmap)->vfs_inode;
 }
diff --git a/fs/nilfs2/cpfile.c b/fs/nilfs2/cpfile.c
index e90b60dfced..300f1cdfa86 100644
--- a/fs/nilfs2/cpfile.c
+++ b/fs/nilfs2/cpfile.c
@@ -311,7 +311,7 @@ int nilfs_cpfile_delete_checkpoints(struct inode *cpfile,
 		ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &cp_bh);
 		if (ret < 0) {
 			if (ret != -ENOENT)
-				goto out_sem;
+				goto out_header;
 			/* skip hole */
 			ret = 0;
 			continue;
@@ -344,7 +344,7 @@ int nilfs_cpfile_delete_checkpoints(struct inode *cpfile,
 					continue;
 				printk(KERN_ERR "%s: cannot delete block\n",
 				       __func__);
-				goto out_sem;
+				goto out_header;
 			}
 		}
 
@@ -361,6 +361,8 @@ int nilfs_cpfile_delete_checkpoints(struct inode *cpfile,
 		nilfs_mdt_mark_dirty(cpfile);
 		kunmap_atomic(kaddr, KM_USER0);
 	}
+
+ out_header:
 	brelse(header_bh);
 
  out_sem:
diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c
index 108d281ebca..d6759b92006 100644
--- a/fs/nilfs2/ioctl.c
+++ b/fs/nilfs2/ioctl.c
@@ -25,6 +25,7 @@
 #include <linux/smp_lock.h>	/* lock_kernel(), unlock_kernel() */
 #include <linux/capability.h>	/* capable() */
 #include <linux/uaccess.h>	/* copy_from_user(), copy_to_user() */
+#include <linux/vmalloc.h>
 #include <linux/nilfs2_fs.h>
 #include "nilfs.h"
 #include "segment.h"
@@ -147,29 +148,12 @@ static ssize_t
 nilfs_ioctl_do_get_cpinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
 			  void *buf, size_t size, size_t nmembs)
 {
-	return nilfs_cpfile_get_cpinfo(nilfs->ns_cpfile, posp, flags, buf,
-				       nmembs);
-}
-
-static int nilfs_ioctl_get_cpinfo(struct inode *inode, struct file *filp,
-				  unsigned int cmd, void __user *argp)
-{
-	struct the_nilfs *nilfs = NILFS_SB(inode->i_sb)->s_nilfs;
-	struct nilfs_argv argv;
 	int ret;
 
-	if (copy_from_user(&argv, argp, sizeof(argv)))
-		return -EFAULT;
-
 	down_read(&nilfs->ns_segctor_sem);
-	ret = nilfs_ioctl_wrap_copy(nilfs, &argv, _IOC_DIR(cmd),
-				    nilfs_ioctl_do_get_cpinfo);
+	ret = nilfs_cpfile_get_cpinfo(nilfs->ns_cpfile, posp, flags, buf,
+				      nmembs);
 	up_read(&nilfs->ns_segctor_sem);
-	if (ret < 0)
-		return ret;
-
-	if (copy_to_user(argp, &argv, sizeof(argv)))
-		ret = -EFAULT;
 	return ret;
 }
 
@@ -195,28 +179,11 @@ static ssize_t
 nilfs_ioctl_do_get_suinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
 			  void *buf, size_t size, size_t nmembs)
 {
-	return nilfs_sufile_get_suinfo(nilfs->ns_sufile, *posp, buf, nmembs);
-}
-
-static int nilfs_ioctl_get_suinfo(struct inode *inode, struct file *filp,
-				  unsigned int cmd, void __user *argp)
-{
-	struct the_nilfs *nilfs = NILFS_SB(inode->i_sb)->s_nilfs;
-	struct nilfs_argv argv;
 	int ret;
 
-	if (copy_from_user(&argv, argp, sizeof(argv)))
-		return -EFAULT;
-
 	down_read(&nilfs->ns_segctor_sem);
-	ret = nilfs_ioctl_wrap_copy(nilfs, &argv, _IOC_DIR(cmd),
-				    nilfs_ioctl_do_get_suinfo);
+	ret = nilfs_sufile_get_suinfo(nilfs->ns_sufile, *posp, buf, nmembs);
 	up_read(&nilfs->ns_segctor_sem);
-	if (ret < 0)
-		return ret;
-
-	if (copy_to_user(argp, &argv, sizeof(argv)))
-		ret = -EFAULT;
 	return ret;
 }
 
@@ -242,28 +209,11 @@ static ssize_t
 nilfs_ioctl_do_get_vinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
 			 void *buf, size_t size, size_t nmembs)
 {
-	return nilfs_dat_get_vinfo(nilfs_dat_inode(nilfs), buf, nmembs);
-}
-
-static int nilfs_ioctl_get_vinfo(struct inode *inode, struct file *filp,
-				 unsigned int cmd, void __user *argp)
-{
-	struct the_nilfs *nilfs = NILFS_SB(inode->i_sb)->s_nilfs;
-	struct nilfs_argv argv;
 	int ret;
 
-	if (copy_from_user(&argv, argp, sizeof(argv)))
-		return -EFAULT;
-
 	down_read(&nilfs->ns_segctor_sem);
-	ret = nilfs_ioctl_wrap_copy(nilfs, &argv, _IOC_DIR(cmd),
-				    nilfs_ioctl_do_get_vinfo);
+	ret = nilfs_dat_get_vinfo(nilfs_dat_inode(nilfs), buf, nmembs);
 	up_read(&nilfs->ns_segctor_sem);
-	if (ret < 0)
-		return ret;
-
-	if (copy_to_user(argp, &argv, sizeof(argv)))
-		ret = -EFAULT;
 	return ret;
 }
 
@@ -276,17 +226,21 @@ nilfs_ioctl_do_get_bdescs(struct the_nilfs *nilfs, __u64 *posp, int flags,
 	struct nilfs_bdesc *bdescs = buf;
 	int ret, i;
 
+	down_read(&nilfs->ns_segctor_sem);
 	for (i = 0; i < nmembs; i++) {
 		ret = nilfs_bmap_lookup_at_level(bmap,
 						 bdescs[i].bd_offset,
 						 bdescs[i].bd_level + 1,
 						 &bdescs[i].bd_blocknr);
 		if (ret < 0) {
-			if (ret != -ENOENT)
+			if (ret != -ENOENT) {
+				up_read(&nilfs->ns_segctor_sem);
 				return ret;
+			}
 			bdescs[i].bd_blocknr = 0;
 		}
 	}
+	up_read(&nilfs->ns_segctor_sem);
 	return nmembs;
 }
 
@@ -300,10 +254,11 @@ static int nilfs_ioctl_get_bdescs(struct inode *inode, struct file *filp,
 	if (copy_from_user(&argv, argp, sizeof(argv)))
 		return -EFAULT;
 
-	down_read(&nilfs->ns_segctor_sem);
+	if (argv.v_size != sizeof(struct nilfs_bdesc))
+		return -EINVAL;
+
 	ret = nilfs_ioctl_wrap_copy(nilfs, &argv, _IOC_DIR(cmd),
 				    nilfs_ioctl_do_get_bdescs);
-	up_read(&nilfs->ns_segctor_sem);
 	if (ret < 0)
 		return ret;
 
@@ -346,10 +301,10 @@ static int nilfs_ioctl_move_inode_block(struct inode *inode,
 	return 0;
 }
 
-static ssize_t
-nilfs_ioctl_do_move_blocks(struct the_nilfs *nilfs, __u64 *posp, int flags,
-			   void *buf, size_t size, size_t nmembs)
+static int nilfs_ioctl_move_blocks(struct the_nilfs *nilfs,
+				   struct nilfs_argv *argv, void *buf)
 {
+	size_t nmembs = argv->v_nmembs;
 	struct inode *inode;
 	struct nilfs_vdesc *vdesc;
 	struct buffer_head *bh, *n;
@@ -410,19 +365,10 @@ nilfs_ioctl_do_move_blocks(struct the_nilfs *nilfs, __u64 *posp, int flags,
 	return ret;
 }
 
-static inline int nilfs_ioctl_move_blocks(struct the_nilfs *nilfs,
-					  struct nilfs_argv *argv,
-					  int dir)
-{
-	return nilfs_ioctl_wrap_copy(nilfs, argv, dir,
-				     nilfs_ioctl_do_move_blocks);
-}
-
-static ssize_t
-nilfs_ioctl_do_delete_checkpoints(struct the_nilfs *nilfs, __u64 *posp,
-				  int flags, void *buf, size_t size,
-				  size_t nmembs)
+static int nilfs_ioctl_delete_checkpoints(struct the_nilfs *nilfs,
+					  struct nilfs_argv *argv, void *buf)
 {
+	size_t nmembs = argv->v_nmembs;
 	struct inode *cpfile = nilfs->ns_cpfile;
 	struct nilfs_period *periods = buf;
 	int ret, i;
@@ -436,36 +382,21 @@ nilfs_ioctl_do_delete_checkpoints(struct the_nilfs *nilfs, __u64 *posp,
 	return nmembs;
 }
 
-static inline int nilfs_ioctl_delete_checkpoints(struct the_nilfs *nilfs,
-						 struct nilfs_argv *argv,
-						 int dir)
+static int nilfs_ioctl_free_vblocknrs(struct the_nilfs *nilfs,
+				      struct nilfs_argv *argv, void *buf)
 {
-	return nilfs_ioctl_wrap_copy(nilfs, argv, dir,
-				     nilfs_ioctl_do_delete_checkpoints);
-}
+	size_t nmembs = argv->v_nmembs;
+	int ret;
 
-static ssize_t
-nilfs_ioctl_do_free_vblocknrs(struct the_nilfs *nilfs, __u64 *posp, int flags,
-			      void *buf, size_t size, size_t nmembs)
-{
-	int ret = nilfs_dat_freev(nilfs_dat_inode(nilfs), buf, nmembs);
+	ret = nilfs_dat_freev(nilfs_dat_inode(nilfs), buf, nmembs);
 
 	return (ret < 0) ? ret : nmembs;
 }
 
-static inline int nilfs_ioctl_free_vblocknrs(struct the_nilfs *nilfs,
-					     struct nilfs_argv *argv,
-					     int dir)
-{
-	return nilfs_ioctl_wrap_copy(nilfs, argv, dir,
-				     nilfs_ioctl_do_free_vblocknrs);
-}
-
-static ssize_t
-nilfs_ioctl_do_mark_blocks_dirty(struct the_nilfs *nilfs, __u64 *posp,
-				 int flags, void *buf, size_t size,
-				 size_t nmembs)
+static int nilfs_ioctl_mark_blocks_dirty(struct the_nilfs *nilfs,
+					 struct nilfs_argv *argv, void *buf)
 {
+	size_t nmembs = argv->v_nmembs;
 	struct inode *dat = nilfs_dat_inode(nilfs);
 	struct nilfs_bmap *bmap = NILFS_I(dat)->i_bmap;
 	struct nilfs_bdesc *bdescs = buf;
@@ -504,55 +435,37 @@ nilfs_ioctl_do_mark_blocks_dirty(struct the_nilfs *nilfs, __u64 *posp,
 	return nmembs;
 }
 
-static inline int nilfs_ioctl_mark_blocks_dirty(struct the_nilfs *nilfs,
-						struct nilfs_argv *argv,
-						int dir)
+static int nilfs_ioctl_free_segments(struct the_nilfs *nilfs,
+				     struct nilfs_argv *argv, void *buf)
 {
-	return nilfs_ioctl_wrap_copy(nilfs, argv, dir,
-				     nilfs_ioctl_do_mark_blocks_dirty);
-}
-
-static ssize_t
-nilfs_ioctl_do_free_segments(struct the_nilfs *nilfs, __u64 *posp, int flags,
-			     void *buf, size_t size, size_t nmembs)
-{
-	struct nilfs_sb_info *sbi = nilfs_get_writer(nilfs);
+	size_t nmembs = argv->v_nmembs;
+	struct nilfs_sb_info *sbi = nilfs->ns_writer;
 	int ret;
 
-	if (unlikely(!sbi))
+	if (unlikely(!sbi)) {
+		/* never happens because called for a writable mount */
+		WARN_ON(1);
 		return -EROFS;
+	}
 	ret = nilfs_segctor_add_segments_to_be_freed(
 		NILFS_SC(sbi), buf, nmembs);
-	nilfs_put_writer(nilfs);
 
 	return (ret < 0) ? ret : nmembs;
 }
 
-static inline int nilfs_ioctl_free_segments(struct the_nilfs *nilfs,
-					     struct nilfs_argv *argv,
-					     int dir)
-{
-	return nilfs_ioctl_wrap_copy(nilfs, argv, dir,
-				     nilfs_ioctl_do_free_segments);
-}
-
 int nilfs_ioctl_prepare_clean_segments(struct the_nilfs *nilfs,
-				       void __user *argp)
+				       struct nilfs_argv *argv, void **kbufs)
 {
-	struct nilfs_argv argv[5];
 	const char *msg;
-	int dir, ret;
-
-	if (copy_from_user(argv, argp, sizeof(argv)))
-		return -EFAULT;
+	int ret;
 
-	dir = _IOC_WRITE;
-	ret = nilfs_ioctl_move_blocks(nilfs, &argv[0], dir);
+	ret = nilfs_ioctl_move_blocks(nilfs, &argv[0], kbufs[0]);
 	if (ret < 0) {
 		msg = "cannot read source blocks";
 		goto failed;
 	}
-	ret = nilfs_ioctl_delete_checkpoints(nilfs, &argv[1], dir);
+
+	ret = nilfs_ioctl_delete_checkpoints(nilfs, &argv[1], kbufs[1]);
 	if (ret < 0) {
 		/*
 		 * can safely abort because checkpoints can be removed
@@ -561,7 +474,7 @@ int nilfs_ioctl_prepare_clean_segments(struct the_nilfs *nilfs,
 		msg = "cannot delete checkpoints";
 		goto failed;
 	}
-	ret = nilfs_ioctl_free_vblocknrs(nilfs, &argv[2], dir);
+	ret = nilfs_ioctl_free_vblocknrs(nilfs, &argv[2], kbufs[2]);
 	if (ret < 0) {
 		/*
 		 * can safely abort because DAT file is updated atomically
@@ -570,7 +483,7 @@ int nilfs_ioctl_prepare_clean_segments(struct the_nilfs *nilfs,
 		msg = "cannot delete virtual blocks from DAT file";
 		goto failed;
 	}
-	ret = nilfs_ioctl_mark_blocks_dirty(nilfs, &argv[3], dir);
+	ret = nilfs_ioctl_mark_blocks_dirty(nilfs, &argv[3], kbufs[3]);
 	if (ret < 0) {
 		/*
 		 * can safely abort because the operation is nondestructive.
@@ -578,7 +491,7 @@ int nilfs_ioctl_prepare_clean_segments(struct the_nilfs *nilfs,
 		msg = "cannot mark copying blocks dirty";
 		goto failed;
 	}
-	ret = nilfs_ioctl_free_segments(nilfs, &argv[4], dir);
+	ret = nilfs_ioctl_free_segments(nilfs, &argv[4], kbufs[4]);
 	if (ret < 0) {
 		/*
 		 * can safely abort because this operation is atomic.
@@ -598,9 +511,75 @@ int nilfs_ioctl_prepare_clean_segments(struct the_nilfs *nilfs,
 static int nilfs_ioctl_clean_segments(struct inode *inode, struct file *filp,
 				      unsigned int cmd, void __user *argp)
 {
+	struct nilfs_argv argv[5];
+	const static size_t argsz[5] = {
+		sizeof(struct nilfs_vdesc),
+		sizeof(struct nilfs_period),
+		sizeof(__u64),
+		sizeof(struct nilfs_bdesc),
+		sizeof(__u64),
+	};
+	void __user *base;
+	void *kbufs[5];
+	struct the_nilfs *nilfs;
+	size_t len, nsegs;
+	int n, ret;
+
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
-	return nilfs_clean_segments(inode->i_sb, argp);
+
+	if (copy_from_user(argv, argp, sizeof(argv)))
+		return -EFAULT;
+
+	nsegs = argv[4].v_nmembs;
+	if (argv[4].v_size != argsz[4])
+		return -EINVAL;
+	/*
+	 * argv[4] points to segment numbers this ioctl cleans.  We
+	 * use kmalloc() for its buffer because memory used for the
+	 * segment numbers is enough small.
+	 */
+	kbufs[4] = memdup_user((void __user *)(unsigned long)argv[4].v_base,
+			       nsegs * sizeof(__u64));
+	if (IS_ERR(kbufs[4]))
+		return PTR_ERR(kbufs[4]);
+
+	nilfs = NILFS_SB(inode->i_sb)->s_nilfs;
+
+	for (n = 0; n < 4; n++) {
+		ret = -EINVAL;
+		if (argv[n].v_size != argsz[n])
+			goto out_free;
+
+		if (argv[n].v_nmembs > nsegs * nilfs->ns_blocks_per_segment)
+			goto out_free;
+
+		len = argv[n].v_size * argv[n].v_nmembs;
+		base = (void __user *)(unsigned long)argv[n].v_base;
+		if (len == 0) {
+			kbufs[n] = NULL;
+			continue;
+		}
+
+		kbufs[n] = vmalloc(len);
+		if (!kbufs[n]) {
+			ret = -ENOMEM;
+			goto out_free;
+		}
+		if (copy_from_user(kbufs[n], base, len)) {
+			ret = -EFAULT;
+			vfree(kbufs[n]);
+			goto out_free;
+		}
+	}
+
+	ret = nilfs_clean_segments(inode->i_sb, argv, kbufs);
+
+ out_free:
+	while (--n >= 0)
+		vfree(kbufs[n]);
+	kfree(kbufs[4]);
+	return ret;
 }
 
 static int nilfs_ioctl_sync(struct inode *inode, struct file *filp,
@@ -621,6 +600,33 @@ static int nilfs_ioctl_sync(struct inode *inode, struct file *filp,
 	return 0;
 }
 
+static int nilfs_ioctl_get_info(struct inode *inode, struct file *filp,
+				unsigned int cmd, void __user *argp,
+				size_t membsz,
+				ssize_t (*dofunc)(struct the_nilfs *,
+						  __u64 *, int,
+						  void *, size_t, size_t))
+
+{
+	struct the_nilfs *nilfs = NILFS_SB(inode->i_sb)->s_nilfs;
+	struct nilfs_argv argv;
+	int ret;
+
+	if (copy_from_user(&argv, argp, sizeof(argv)))
+		return -EFAULT;
+
+	if (argv.v_size != membsz)
+		return -EINVAL;
+
+	ret = nilfs_ioctl_wrap_copy(nilfs, &argv, _IOC_DIR(cmd), dofunc);
+	if (ret < 0)
+		return ret;
+
+	if (copy_to_user(argp, &argv, sizeof(argv)))
+		ret = -EFAULT;
+	return ret;
+}
+
 long nilfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 {
 	struct inode *inode = filp->f_dentry->d_inode;
@@ -632,16 +638,21 @@ long nilfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 	case NILFS_IOCTL_DELETE_CHECKPOINT:
 		return nilfs_ioctl_delete_checkpoint(inode, filp, cmd, argp);
 	case NILFS_IOCTL_GET_CPINFO:
-		return nilfs_ioctl_get_cpinfo(inode, filp, cmd, argp);
+		return nilfs_ioctl_get_info(inode, filp, cmd, argp,
+					    sizeof(struct nilfs_cpinfo),
+					    nilfs_ioctl_do_get_cpinfo);
 	case NILFS_IOCTL_GET_CPSTAT:
 		return nilfs_ioctl_get_cpstat(inode, filp, cmd, argp);
 	case NILFS_IOCTL_GET_SUINFO:
-		return nilfs_ioctl_get_suinfo(inode, filp, cmd, argp);
+		return nilfs_ioctl_get_info(inode, filp, cmd, argp,
+					    sizeof(struct nilfs_suinfo),
+					    nilfs_ioctl_do_get_suinfo);
 	case NILFS_IOCTL_GET_SUSTAT:
 		return nilfs_ioctl_get_sustat(inode, filp, cmd, argp);
 	case NILFS_IOCTL_GET_VINFO:
-		/* XXX: rename to ??? */
-		return nilfs_ioctl_get_vinfo(inode, filp, cmd, argp);
+		return nilfs_ioctl_get_info(inode, filp, cmd, argp,
+					    sizeof(struct nilfs_vinfo),
+					    nilfs_ioctl_do_get_vinfo);
 	case NILFS_IOCTL_GET_BDESCS:
 		return nilfs_ioctl_get_bdescs(inode, filp, cmd, argp);
 	case NILFS_IOCTL_CLEAN_SEGMENTS:
diff --git a/fs/nilfs2/mdt.c b/fs/nilfs2/mdt.c
index 47dd815433f..bb78745a0e3 100644
--- a/fs/nilfs2/mdt.c
+++ b/fs/nilfs2/mdt.c
@@ -77,19 +77,22 @@ static int nilfs_mdt_create_block(struct inode *inode, unsigned long block,
 						     void *))
 {
 	struct the_nilfs *nilfs = NILFS_MDT(inode)->mi_nilfs;
-	struct nilfs_sb_info *writer = NULL;
 	struct super_block *sb = inode->i_sb;
 	struct nilfs_transaction_info ti;
 	struct buffer_head *bh;
 	int err;
 
 	if (!sb) {
-		writer = nilfs_get_writer(nilfs);
-		if (!writer) {
+		/*
+		 * Make sure this function is not called from any
+		 * read-only context.
+		 */
+		if (!nilfs->ns_writer) {
+			WARN_ON(1);
 			err = -EROFS;
 			goto out;
 		}
-		sb = writer->s_super;
+		sb = nilfs->ns_writer->s_super;
 	}
 
 	nilfs_transaction_begin(sb, &ti, 0);
@@ -127,8 +130,6 @@ static int nilfs_mdt_create_block(struct inode *inode, unsigned long block,
 		err = nilfs_transaction_commit(sb);
 	else
 		nilfs_transaction_abort(sb);
-	if (writer)
-		nilfs_put_writer(nilfs);
  out:
 	return err;
 }
@@ -299,7 +300,7 @@ int nilfs_mdt_delete_block(struct inode *inode, unsigned long block)
 	int err;
 
 	err = nilfs_bmap_delete(ii->i_bmap, block);
-	if (likely(!err)) {
+	if (!err || err == -ENOENT) {
 		nilfs_mdt_mark_dirty(inode);
 		nilfs_mdt_forget_block(inode, block);
 	}
diff --git a/fs/nilfs2/nilfs.h b/fs/nilfs2/nilfs.h
index 7558c977db0..da6fc0bba2e 100644
--- a/fs/nilfs2/nilfs.h
+++ b/fs/nilfs2/nilfs.h
@@ -35,11 +35,6 @@
 #include "bmap_union.h"
 
 /*
- * NILFS filesystem version
- */
-#define NILFS_VERSION		"2.0.5"
-
-/*
  * nilfs inode data in memory
  */
 struct nilfs_inode_info {
@@ -241,7 +236,8 @@ extern int nilfs_sync_file(struct file *, struct dentry *, int);
 
 /* ioctl.c */
 long nilfs_ioctl(struct file *, unsigned int, unsigned long);
-int nilfs_ioctl_prepare_clean_segments(struct the_nilfs *, void __user *);
+int nilfs_ioctl_prepare_clean_segments(struct the_nilfs *, struct nilfs_argv *,
+				       void **);
 
 /* inode.c */
 extern struct inode *nilfs_new_inode(struct inode *, int);
diff --git a/fs/nilfs2/page.c b/fs/nilfs2/page.c
index 1bfbba9c0e9..a2692bbc7b5 100644
--- a/fs/nilfs2/page.c
+++ b/fs/nilfs2/page.c
@@ -128,7 +128,8 @@ void nilfs_forget_buffer(struct buffer_head *bh)
 
 	lock_buffer(bh);
 	clear_buffer_nilfs_volatile(bh);
-	if (test_clear_buffer_dirty(bh) && nilfs_page_buffers_clean(page))
+	clear_buffer_dirty(bh);
+	if (nilfs_page_buffers_clean(page))
 		__nilfs_clear_page_dirty(page);
 
 	clear_buffer_uptodate(bh);
diff --git a/fs/nilfs2/recovery.c b/fs/nilfs2/recovery.c
index 6ade0963fc1..57afa9d2406 100644
--- a/fs/nilfs2/recovery.c
+++ b/fs/nilfs2/recovery.c
@@ -407,13 +407,13 @@ void nilfs_dispose_segment_list(struct list_head *head)
 }
 
 static int nilfs_prepare_segment_for_recovery(struct the_nilfs *nilfs,
+					      struct nilfs_sb_info *sbi,
 					      struct nilfs_recovery_info *ri)
 {
 	struct list_head *head = &ri->ri_used_segments;
 	struct nilfs_segment_entry *ent, *n;
 	struct inode *sufile = nilfs->ns_sufile;
 	__u64 segnum[4];
-	time_t mtime;
 	int err;
 	int i;
 
@@ -422,6 +422,7 @@ static int nilfs_prepare_segment_for_recovery(struct the_nilfs *nilfs,
 	segnum[2] = ri->ri_segnum;
 	segnum[3] = ri->ri_nextnum;
 
+	nilfs_attach_writer(nilfs, sbi);
 	/*
 	 * Releasing the next segment of the latest super root.
 	 * The next segment is invalidated by this recovery.
@@ -442,24 +443,13 @@ static int nilfs_prepare_segment_for_recovery(struct the_nilfs *nilfs,
 	 * Collecting segments written after the latest super root.
 	 * These are marked dirty to avoid being reallocated in the next write.
 	 */
-	mtime = get_seconds();
 	list_for_each_entry_safe(ent, n, head, list) {
-		if (ent->segnum == segnum[0]) {
-			list_del(&ent->list);
-			nilfs_free_segment_entry(ent);
-			continue;
-		}
-		err = nilfs_open_segment_entry(ent, sufile);
-		if (unlikely(err))
-			goto failed;
-		if (!nilfs_segment_usage_dirty(ent->raw_su)) {
-			/* make the segment garbage */
-			ent->raw_su->su_nblocks = cpu_to_le32(0);
-			ent->raw_su->su_lastmod = cpu_to_le32(mtime);
-			nilfs_segment_usage_set_dirty(ent->raw_su);
+		if (ent->segnum != segnum[0]) {
+			err = nilfs_sufile_scrap(sufile, ent->segnum);
+			if (unlikely(err))
+				goto failed;
 		}
 		list_del(&ent->list);
-		nilfs_close_segment_entry(ent, sufile);
 		nilfs_free_segment_entry(ent);
 	}
 
@@ -471,10 +461,10 @@ static int nilfs_prepare_segment_for_recovery(struct the_nilfs *nilfs,
 	nilfs->ns_pseg_offset = 0;
 	nilfs->ns_seg_seq = ri->ri_seq + 2;
 	nilfs->ns_nextnum = nilfs->ns_segnum = segnum[0];
-	return 0;
 
  failed:
 	/* No need to recover sufile because it will be destroyed on error */
+	nilfs_detach_writer(nilfs, sbi);
 	return err;
 }
 
@@ -740,7 +730,7 @@ int nilfs_recover_logical_segments(struct the_nilfs *nilfs,
 		goto failed;
 
 	if (ri->ri_need_recovery == NILFS_RECOVERY_ROLLFORWARD_DONE) {
-		err = nilfs_prepare_segment_for_recovery(nilfs, ri);
+		err = nilfs_prepare_segment_for_recovery(nilfs, sbi, ri);
 		if (unlikely(err)) {
 			printk(KERN_ERR "NILFS: Error preparing segments for "
 			       "recovery.\n");
diff --git a/fs/nilfs2/segment.c b/fs/nilfs2/segment.c
index fb70ec3be20..22c7f65c240 100644
--- a/fs/nilfs2/segment.c
+++ b/fs/nilfs2/segment.c
@@ -2589,7 +2589,8 @@ nilfs_remove_written_gcinodes(struct the_nilfs *nilfs, struct list_head *head)
 	}
 }
 
-int nilfs_clean_segments(struct super_block *sb, void __user *argp)
+int nilfs_clean_segments(struct super_block *sb, struct nilfs_argv *argv,
+			 void **kbufs)
 {
 	struct nilfs_sb_info *sbi = NILFS_SB(sb);
 	struct nilfs_sc_info *sci = NILFS_SC(sbi);
@@ -2606,7 +2607,7 @@ int nilfs_clean_segments(struct super_block *sb, void __user *argp)
 	err = nilfs_init_gcdat_inode(nilfs);
 	if (unlikely(err))
 		goto out_unlock;
-	err = nilfs_ioctl_prepare_clean_segments(nilfs, argp);
+	err = nilfs_ioctl_prepare_clean_segments(nilfs, argv, kbufs);
 	if (unlikely(err))
 		goto out_unlock;
 
diff --git a/fs/nilfs2/segment.h b/fs/nilfs2/segment.h
index a98fc1ed0bb..476bdd5df5b 100644
--- a/fs/nilfs2/segment.h
+++ b/fs/nilfs2/segment.h
@@ -222,7 +222,8 @@ extern int nilfs_construct_segment(struct super_block *);
 extern int nilfs_construct_dsync_segment(struct super_block *, struct inode *,
 					 loff_t, loff_t);
 extern void nilfs_flush_segment(struct super_block *, ino_t);
-extern int nilfs_clean_segments(struct super_block *, void __user *);
+extern int nilfs_clean_segments(struct super_block *, struct nilfs_argv *,
+				void **);
 
 extern int nilfs_segctor_add_segments_to_be_freed(struct nilfs_sc_info *,
 						  __u64 *, size_t);
diff --git a/fs/nilfs2/sufile.c b/fs/nilfs2/sufile.c
index c774cf397e2..98e68677f04 100644
--- a/fs/nilfs2/sufile.c
+++ b/fs/nilfs2/sufile.c
@@ -93,6 +93,52 @@ nilfs_sufile_get_segment_usage_block(struct inode *sufile, __u64 segnum,
 				   create, NULL, bhp);
 }
 
+static void nilfs_sufile_mod_counter(struct buffer_head *header_bh,
+				     u64 ncleanadd, u64 ndirtyadd)
+{
+	struct nilfs_sufile_header *header;
+	void *kaddr;
+
+	kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
+	header = kaddr + bh_offset(header_bh);
+	le64_add_cpu(&header->sh_ncleansegs, ncleanadd);
+	le64_add_cpu(&header->sh_ndirtysegs, ndirtyadd);
+	kunmap_atomic(kaddr, KM_USER0);
+
+	nilfs_mdt_mark_buffer_dirty(header_bh);
+}
+
+int nilfs_sufile_update(struct inode *sufile, __u64 segnum, int create,
+			void (*dofunc)(struct inode *, __u64,
+				       struct buffer_head *,
+				       struct buffer_head *))
+{
+	struct buffer_head *header_bh, *bh;
+	int ret;
+
+	if (unlikely(segnum >= nilfs_sufile_get_nsegments(sufile))) {
+		printk(KERN_WARNING "%s: invalid segment number: %llu\n",
+		       __func__, (unsigned long long)segnum);
+		return -EINVAL;
+	}
+	down_write(&NILFS_MDT(sufile)->mi_sem);
+
+	ret = nilfs_sufile_get_header_block(sufile, &header_bh);
+	if (ret < 0)
+		goto out_sem;
+
+	ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, create, &bh);
+	if (!ret) {
+		dofunc(sufile, segnum, header_bh, bh);
+		brelse(bh);
+	}
+	brelse(header_bh);
+
+ out_sem:
+	up_write(&NILFS_MDT(sufile)->mi_sem);
+	return ret;
+}
+
 /**
  * nilfs_sufile_alloc - allocate a segment
  * @sufile: inode of segment usage file
@@ -113,7 +159,6 @@ nilfs_sufile_get_segment_usage_block(struct inode *sufile, __u64 segnum,
 int nilfs_sufile_alloc(struct inode *sufile, __u64 *segnump)
 {
 	struct buffer_head *header_bh, *su_bh;
-	struct the_nilfs *nilfs;
 	struct nilfs_sufile_header *header;
 	struct nilfs_segment_usage *su;
 	size_t susz = NILFS_MDT(sufile)->mi_entry_size;
@@ -124,8 +169,6 @@ int nilfs_sufile_alloc(struct inode *sufile, __u64 *segnump)
 
 	down_write(&NILFS_MDT(sufile)->mi_sem);
 
-	nilfs = NILFS_MDT(sufile)->mi_nilfs;
-
 	ret = nilfs_sufile_get_header_block(sufile, &header_bh);
 	if (ret < 0)
 		goto out_sem;
@@ -192,165 +235,84 @@ int nilfs_sufile_alloc(struct inode *sufile, __u64 *segnump)
 	return ret;
 }
 
-/**
- * nilfs_sufile_cancel_free -
- * @sufile: inode of segment usage file
- * @segnum: segment number
- *
- * Description:
- *
- * Return Value: On success, 0 is returned. On error, one of the following
- * negative error codes is returned.
- *
- * %-EIO - I/O error.
- *
- * %-ENOMEM - Insufficient amount of memory available.
- */
-int nilfs_sufile_cancel_free(struct inode *sufile, __u64 segnum)
+void nilfs_sufile_do_cancel_free(struct inode *sufile, __u64 segnum,
+				 struct buffer_head *header_bh,
+				 struct buffer_head *su_bh)
 {
-	struct buffer_head *header_bh, *su_bh;
-	struct the_nilfs *nilfs;
-	struct nilfs_sufile_header *header;
 	struct nilfs_segment_usage *su;
 	void *kaddr;
-	int ret;
-
-	down_write(&NILFS_MDT(sufile)->mi_sem);
-
-	nilfs = NILFS_MDT(sufile)->mi_nilfs;
-
-	ret = nilfs_sufile_get_header_block(sufile, &header_bh);
-	if (ret < 0)
-		goto out_sem;
-
-	ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &su_bh);
-	if (ret < 0)
-		goto out_header;
 
 	kaddr = kmap_atomic(su_bh->b_page, KM_USER0);
-	su = nilfs_sufile_block_get_segment_usage(
-		sufile, segnum, su_bh, kaddr);
+	su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
 	if (unlikely(!nilfs_segment_usage_clean(su))) {
 		printk(KERN_WARNING "%s: segment %llu must be clean\n",
 		       __func__, (unsigned long long)segnum);
 		kunmap_atomic(kaddr, KM_USER0);
-		goto out_su_bh;
+		return;
 	}
 	nilfs_segment_usage_set_dirty(su);
 	kunmap_atomic(kaddr, KM_USER0);
 
-	kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
-	header = nilfs_sufile_block_get_header(sufile, header_bh, kaddr);
-	le64_add_cpu(&header->sh_ncleansegs, -1);
-	le64_add_cpu(&header->sh_ndirtysegs, 1);
-	kunmap_atomic(kaddr, KM_USER0);
-
-	nilfs_mdt_mark_buffer_dirty(header_bh);
+	nilfs_sufile_mod_counter(header_bh, -1, 1);
 	nilfs_mdt_mark_buffer_dirty(su_bh);
 	nilfs_mdt_mark_dirty(sufile);
-
- out_su_bh:
-	brelse(su_bh);
- out_header:
-	brelse(header_bh);
- out_sem:
-	up_write(&NILFS_MDT(sufile)->mi_sem);
-	return ret;
 }
 
-/**
- * nilfs_sufile_freev - free segments
- * @sufile: inode of segment usage file
- * @segnum: array of segment numbers
- * @nsegs: number of segments
- *
- * Description: nilfs_sufile_freev() frees segments specified by @segnum and
- * @nsegs, which must have been returned by a previous call to
- * nilfs_sufile_alloc().
- *
- * Return Value: On success, 0 is returned. On error, one of the following
- * negative error codes is returned.
- *
- * %-EIO - I/O error.
- *
- * %-ENOMEM - Insufficient amount of memory available.
- */
-#define NILFS_SUFILE_FREEV_PREALLOC	16
-int nilfs_sufile_freev(struct inode *sufile, __u64 *segnum, size_t nsegs)
+void nilfs_sufile_do_scrap(struct inode *sufile, __u64 segnum,
+			   struct buffer_head *header_bh,
+			   struct buffer_head *su_bh)
 {
-	struct buffer_head *header_bh, **su_bh,
-		*su_bh_prealloc[NILFS_SUFILE_FREEV_PREALLOC];
-	struct the_nilfs *nilfs;
-	struct nilfs_sufile_header *header;
 	struct nilfs_segment_usage *su;
 	void *kaddr;
-	int ret, i;
+	int clean, dirty;
 
-	down_write(&NILFS_MDT(sufile)->mi_sem);
-
-	nilfs = NILFS_MDT(sufile)->mi_nilfs;
-
-	/* prepare resources */
-	if (nsegs <= NILFS_SUFILE_FREEV_PREALLOC)
-		su_bh = su_bh_prealloc;
-	else {
-		su_bh = kmalloc(sizeof(*su_bh) * nsegs, GFP_NOFS);
-		if (su_bh == NULL) {
-			ret = -ENOMEM;
-			goto out_sem;
-		}
-	}
-
-	ret = nilfs_sufile_get_header_block(sufile, &header_bh);
-	if (ret < 0)
-		goto out_su_bh;
-	for (i = 0; i < nsegs; i++) {
-		ret = nilfs_sufile_get_segment_usage_block(sufile, segnum[i],
-							   0, &su_bh[i]);
-		if (ret < 0)
-			goto out_bh;
-	}
-
-	/* free segments */
-	for (i = 0; i < nsegs; i++) {
-		kaddr = kmap_atomic(su_bh[i]->b_page, KM_USER0);
-		su = nilfs_sufile_block_get_segment_usage(
-			sufile, segnum[i], su_bh[i], kaddr);
-		WARN_ON(nilfs_segment_usage_error(su));
-		nilfs_segment_usage_set_clean(su);
+	kaddr = kmap_atomic(su_bh->b_page, KM_USER0);
+	su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
+	if (su->su_flags == cpu_to_le32(1UL << NILFS_SEGMENT_USAGE_DIRTY) &&
+	    su->su_nblocks == cpu_to_le32(0)) {
 		kunmap_atomic(kaddr, KM_USER0);
-		nilfs_mdt_mark_buffer_dirty(su_bh[i]);
+		return;
 	}
-	kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
-	header = nilfs_sufile_block_get_header(sufile, header_bh, kaddr);
-	le64_add_cpu(&header->sh_ncleansegs, nsegs);
-	le64_add_cpu(&header->sh_ndirtysegs, -(u64)nsegs);
+	clean = nilfs_segment_usage_clean(su);
+	dirty = nilfs_segment_usage_dirty(su);
+
+	/* make the segment garbage */
+	su->su_lastmod = cpu_to_le64(0);
+	su->su_nblocks = cpu_to_le32(0);
+	su->su_flags = cpu_to_le32(1UL << NILFS_SEGMENT_USAGE_DIRTY);
 	kunmap_atomic(kaddr, KM_USER0);
-	nilfs_mdt_mark_buffer_dirty(header_bh);
+
+	nilfs_sufile_mod_counter(header_bh, clean ? (u64)-1 : 0, dirty ? 0 : 1);
+	nilfs_mdt_mark_buffer_dirty(su_bh);
 	nilfs_mdt_mark_dirty(sufile);
+}
 
- out_bh:
-	for (i--; i >= 0; i--)
-		brelse(su_bh[i]);
-	brelse(header_bh);
+void nilfs_sufile_do_free(struct inode *sufile, __u64 segnum,
+			  struct buffer_head *header_bh,
+			  struct buffer_head *su_bh)
+{
+	struct nilfs_segment_usage *su;
+	void *kaddr;
+	int sudirty;
 
- out_su_bh:
-	if (su_bh != su_bh_prealloc)
-		kfree(su_bh);
+	kaddr = kmap_atomic(su_bh->b_page, KM_USER0);
+	su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
+	if (nilfs_segment_usage_clean(su)) {
+		printk(KERN_WARNING "%s: segment %llu is already clean\n",
+		       __func__, (unsigned long long)segnum);
+		kunmap_atomic(kaddr, KM_USER0);
+		return;
+	}
+	WARN_ON(nilfs_segment_usage_error(su));
+	WARN_ON(!nilfs_segment_usage_dirty(su));
 
- out_sem:
-	up_write(&NILFS_MDT(sufile)->mi_sem);
-	return ret;
-}
+	sudirty = nilfs_segment_usage_dirty(su);
+	nilfs_segment_usage_set_clean(su);
+	kunmap_atomic(kaddr, KM_USER0);
+	nilfs_mdt_mark_buffer_dirty(su_bh);
 
-/**
- * nilfs_sufile_free -
- * @sufile:
- * @segnum:
- */
-int nilfs_sufile_free(struct inode *sufile, __u64 segnum)
-{
-	return nilfs_sufile_freev(sufile, &segnum, 1);
+	nilfs_sufile_mod_counter(header_bh, 1, sudirty ? (u64)-1 : 0);
+	nilfs_mdt_mark_dirty(sufile);
 }
 
 /**
@@ -500,72 +462,28 @@ int nilfs_sufile_get_ncleansegs(struct inode *sufile, unsigned long *nsegsp)
 	return ret;
 }
 
-/**
- * nilfs_sufile_set_error - mark a segment as erroneous
- * @sufile: inode of segment usage file
- * @segnum: segment number
- *
- * Description: nilfs_sufile_set_error() marks the segment specified by
- * @segnum as erroneous. The error segment will never be used again.
- *
- * Return Value: On success, 0 is returned. On error, one of the following
- * negative error codes is returned.
- *
- * %-EIO - I/O error.
- *
- * %-ENOMEM - Insufficient amount of memory available.
- *
- * %-EINVAL - Invalid segment usage number.
- */
-int nilfs_sufile_set_error(struct inode *sufile, __u64 segnum)
+void nilfs_sufile_do_set_error(struct inode *sufile, __u64 segnum,
+			       struct buffer_head *header_bh,
+			       struct buffer_head *su_bh)
 {
-	struct buffer_head *header_bh, *su_bh;
 	struct nilfs_segment_usage *su;
-	struct nilfs_sufile_header *header;
 	void *kaddr;
-	int ret;
-
-	if (unlikely(segnum >= nilfs_sufile_get_nsegments(sufile))) {
-		printk(KERN_WARNING "%s: invalid segment number: %llu\n",
-		       __func__, (unsigned long long)segnum);
-		return -EINVAL;
-	}
-	down_write(&NILFS_MDT(sufile)->mi_sem);
-
-	ret = nilfs_sufile_get_header_block(sufile, &header_bh);
-	if (ret < 0)
-		goto out_sem;
-	ret = nilfs_sufile_get_segment_usage_block(sufile, segnum, 0, &su_bh);
-	if (ret < 0)
-		goto out_header;
+	int suclean;
 
 	kaddr = kmap_atomic(su_bh->b_page, KM_USER0);
 	su = nilfs_sufile_block_get_segment_usage(sufile, segnum, su_bh, kaddr);
 	if (nilfs_segment_usage_error(su)) {
 		kunmap_atomic(kaddr, KM_USER0);
-		brelse(su_bh);
-		goto out_header;
+		return;
 	}
-
+	suclean = nilfs_segment_usage_clean(su);
 	nilfs_segment_usage_set_error(su);
 	kunmap_atomic(kaddr, KM_USER0);
-	brelse(su_bh);
 
-	kaddr = kmap_atomic(header_bh->b_page, KM_USER0);
-	header = nilfs_sufile_block_get_header(sufile, header_bh, kaddr);
-	le64_add_cpu(&header->sh_ndirtysegs, -1);
-	kunmap_atomic(kaddr, KM_USER0);
-	nilfs_mdt_mark_buffer_dirty(header_bh);
+	if (suclean)
+		nilfs_sufile_mod_counter(header_bh, -1, 0);
 	nilfs_mdt_mark_buffer_dirty(su_bh);
 	nilfs_mdt_mark_dirty(sufile);
-	brelse(su_bh);
-
- out_header:
-	brelse(header_bh);
-
- out_sem:
-	up_write(&NILFS_MDT(sufile)->mi_sem);
-	return ret;
 }
 
 /**
@@ -625,7 +543,7 @@ ssize_t nilfs_sufile_get_suinfo(struct inode *sufile, __u64 segnum,
 			si[i + j].sui_nblocks = le32_to_cpu(su->su_nblocks);
 			si[i + j].sui_flags = le32_to_cpu(su->su_flags) &
 				~(1UL << NILFS_SEGMENT_USAGE_ACTIVE);
-			if (nilfs_segment_is_active(nilfs, segnum + i + j))
+			if (nilfs_segment_is_active(nilfs, segnum + j))
 				si[i + j].sui_flags |=
 					(1UL << NILFS_SEGMENT_USAGE_ACTIVE);
 		}
diff --git a/fs/nilfs2/sufile.h b/fs/nilfs2/sufile.h
index d595f33a768..a2e2efd4ade 100644
--- a/fs/nilfs2/sufile.h
+++ b/fs/nilfs2/sufile.h
@@ -36,9 +36,6 @@ static inline unsigned long nilfs_sufile_get_nsegments(struct inode *sufile)
 }
 
 int nilfs_sufile_alloc(struct inode *, __u64 *);
-int nilfs_sufile_cancel_free(struct inode *, __u64);
-int nilfs_sufile_freev(struct inode *, __u64 *, size_t);
-int nilfs_sufile_free(struct inode *, __u64);
 int nilfs_sufile_get_segment_usage(struct inode *, __u64,
 				   struct nilfs_segment_usage **,
 				   struct buffer_head **);
@@ -46,9 +43,83 @@ void nilfs_sufile_put_segment_usage(struct inode *, __u64,
 				    struct buffer_head *);
 int nilfs_sufile_get_stat(struct inode *, struct nilfs_sustat *);
 int nilfs_sufile_get_ncleansegs(struct inode *, unsigned long *);
-int nilfs_sufile_set_error(struct inode *, __u64);
 ssize_t nilfs_sufile_get_suinfo(struct inode *, __u64, struct nilfs_suinfo *,
 				size_t);
 
+int nilfs_sufile_update(struct inode *, __u64, int,
+			void (*dofunc)(struct inode *, __u64,
+				       struct buffer_head *,
+				       struct buffer_head *));
+void nilfs_sufile_do_cancel_free(struct inode *, __u64, struct buffer_head *,
+				 struct buffer_head *);
+void nilfs_sufile_do_scrap(struct inode *, __u64, struct buffer_head *,
+			   struct buffer_head *);
+void nilfs_sufile_do_free(struct inode *, __u64, struct buffer_head *,
+			  struct buffer_head *);
+void nilfs_sufile_do_set_error(struct inode *, __u64, struct buffer_head *,
+			       struct buffer_head *);
+
+/**
+ * nilfs_sufile_cancel_free -
+ * @sufile: inode of segment usage file
+ * @segnum: segment number
+ *
+ * Description:
+ *
+ * Return Value: On success, 0 is returned. On error, one of the following
+ * negative error codes is returned.
+ *
+ * %-EIO - I/O error.
+ *
+ * %-ENOMEM - Insufficient amount of memory available.
+ */
+static inline int nilfs_sufile_cancel_free(struct inode *sufile, __u64 segnum)
+{
+	return nilfs_sufile_update(sufile, segnum, 0,
+				   nilfs_sufile_do_cancel_free);
+}
+
+/**
+ * nilfs_sufile_scrap - make a segment garbage
+ * @sufile: inode of segment usage file
+ * @segnum: segment number to be freed
+ */
+static inline int nilfs_sufile_scrap(struct inode *sufile, __u64 segnum)
+{
+	return nilfs_sufile_update(sufile, segnum, 1, nilfs_sufile_do_scrap);
+}
+
+/**
+ * nilfs_sufile_free - free segment
+ * @sufile: inode of segment usage file
+ * @segnum: segment number to be freed
+ */
+static inline int nilfs_sufile_free(struct inode *sufile, __u64 segnum)
+{
+	return nilfs_sufile_update(sufile, segnum, 0, nilfs_sufile_do_free);
+}
+
+/**
+ * nilfs_sufile_set_error - mark a segment as erroneous
+ * @sufile: inode of segment usage file
+ * @segnum: segment number
+ *
+ * Description: nilfs_sufile_set_error() marks the segment specified by
+ * @segnum as erroneous. The error segment will never be used again.
+ *
+ * Return Value: On success, 0 is returned. On error, one of the following
+ * negative error codes is returned.
+ *
+ * %-EIO - I/O error.
+ *
+ * %-ENOMEM - Insufficient amount of memory available.
+ *
+ * %-EINVAL - Invalid segment usage number.
+ */
+static inline int nilfs_sufile_set_error(struct inode *sufile, __u64 segnum)
+{
+	return nilfs_sufile_update(sufile, segnum, 0,
+				   nilfs_sufile_do_set_error);
+}
 
 #endif	/* _NILFS_SUFILE_H */
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index e117e1ea9bf..6989b03e97a 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -63,7 +63,6 @@
 MODULE_AUTHOR("NTT Corp.");
 MODULE_DESCRIPTION("A New Implementation of the Log-structured Filesystem "
 		   "(NILFS)");
-MODULE_VERSION(NILFS_VERSION);
 MODULE_LICENSE("GPL");
 
 static int nilfs_remount(struct super_block *sb, int *flags, char *data);
@@ -476,11 +475,12 @@ static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 {
 	struct super_block *sb = dentry->d_sb;
 	struct nilfs_sb_info *sbi = NILFS_SB(sb);
+	struct the_nilfs *nilfs = sbi->s_nilfs;
+	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
 	unsigned long long blocks;
 	unsigned long overhead;
 	unsigned long nrsvblocks;
 	sector_t nfreeblocks;
-	struct the_nilfs *nilfs = sbi->s_nilfs;
 	int err;
 
 	/*
@@ -514,6 +514,9 @@ static int nilfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 	buf->f_files = atomic_read(&sbi->s_inodes_count);
 	buf->f_ffree = 0; /* nilfs_count_free_inodes(sb); */
 	buf->f_namelen = NILFS_NAME_LEN;
+	buf->f_fsid.val[0] = (u32)id;
+	buf->f_fsid.val[1] = (u32)(id >> 32);
+
 	return 0;
 }
 
diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c
index 33400cf0bbe..7f65b3be4aa 100644
--- a/fs/nilfs2/the_nilfs.c
+++ b/fs/nilfs2/the_nilfs.c
@@ -115,6 +115,7 @@ void put_nilfs(struct the_nilfs *nilfs)
 static int nilfs_load_super_root(struct the_nilfs *nilfs,
 				 struct nilfs_sb_info *sbi, sector_t sr_block)
 {
+	static struct lock_class_key dat_lock_key;
 	struct buffer_head *bh_sr;
 	struct nilfs_super_root *raw_sr;
 	struct nilfs_super_block **sbp = nilfs->ns_sbp;
@@ -163,6 +164,9 @@ static int nilfs_load_super_root(struct the_nilfs *nilfs,
 	if (unlikely(err))
 		goto failed_sufile;
 
+	lockdep_set_class(&NILFS_MDT(nilfs->ns_dat)->mi_sem, &dat_lock_key);
+	lockdep_set_class(&NILFS_MDT(nilfs->ns_gc_dat)->mi_sem, &dat_lock_key);
+
 	nilfs_mdt_set_shadow(nilfs->ns_dat, nilfs->ns_gc_dat);
 	nilfs_mdt_set_entry_size(nilfs->ns_cpfile, checkpoint_size,
 				 sizeof(struct nilfs_cpfile_header));