11 files changed, 252 insertions, 204 deletions

diff --git a/fs/ocfs2/buffer_head_io.c b/fs/ocfs2/buffer_head_io.c
index 1d098c3c00e0..4ebbd57cbf84 100644
--- a/fs/ocfs2/buffer_head_io.c
+++ b/fs/ocfs2/buffer_head_io.c
@@ -99,25 +99,34 @@ out:
 	return ret;
 }
 
+/* Caller must provide a bhs[] with all NULL or non-NULL entries, so it
+ * will be easier to handle read failure.
+ */
 int ocfs2_read_blocks_sync(struct ocfs2_super *osb, u64 block,
 			   unsigned int nr, struct buffer_head *bhs[])
 {
 	int status = 0;
 	unsigned int i;
 	struct buffer_head *bh;
+	int new_bh = 0;
 
 	trace_ocfs2_read_blocks_sync((unsigned long long)block, nr);
 
 	if (!nr)
 		goto bail;
 
+	/* Don't put buffer head and re-assign it to NULL if it is allocated
+	 * outside since the caller can't be aware of this alternation!
+	 */
+	new_bh = (bhs[0] == NULL);
+
 	for (i = 0 ; i < nr ; i++) {
 		if (bhs[i] == NULL) {
 			bhs[i] = sb_getblk(osb->sb, block++);
 			if (bhs[i] == NULL) {
 				status = -ENOMEM;
 				mlog_errno(status);
-				goto bail;
+				break;
 			}
 		}
 		bh = bhs[i];
@@ -158,9 +167,26 @@ int ocfs2_read_blocks_sync(struct ocfs2_super *osb, u64 block,
 		submit_bh(REQ_OP_READ, 0, bh);
 	}
 
+read_failure:
 	for (i = nr; i > 0; i--) {
 		bh = bhs[i - 1];
 
+		if (unlikely(status)) {
+			if (new_bh && bh) {
+				/* If middle bh fails, let previous bh
+				 * finish its read and then put it to
+				 * aovoid bh leak
+				 */
+				if (!buffer_jbd(bh))
+					wait_on_buffer(bh);
+				put_bh(bh);
+				bhs[i - 1] = NULL;
+			} else if (bh && buffer_uptodate(bh)) {
+				clear_buffer_uptodate(bh);
+			}
+			continue;
+		}
+
 		/* No need to wait on the buffer if it's managed by JBD. */
 		if (!buffer_jbd(bh))
 			wait_on_buffer(bh);
@@ -170,8 +196,7 @@ int ocfs2_read_blocks_sync(struct ocfs2_super *osb, u64 block,
 			 * so we can safely record this and loop back
 			 * to cleanup the other buffers. */
 			status = -EIO;
-			put_bh(bh);
-			bhs[i - 1] = NULL;
+			goto read_failure;
 		}
 	}
 
@@ -179,6 +204,9 @@ bail:
 	return status;
 }
 
+/* Caller must provide a bhs[] with all NULL or non-NULL entries, so it
+ * will be easier to handle read failure.
+ */
 int ocfs2_read_blocks(struct ocfs2_caching_info *ci, u64 block, int nr,
 		      struct buffer_head *bhs[], int flags,
 		      int (*validate)(struct super_block *sb,
@@ -188,6 +216,7 @@ int ocfs2_read_blocks(struct ocfs2_caching_info *ci, u64 block, int nr,
 	int i, ignore_cache = 0;
 	struct buffer_head *bh;
 	struct super_block *sb = ocfs2_metadata_cache_get_super(ci);
+	int new_bh = 0;
 
 	trace_ocfs2_read_blocks_begin(ci, (unsigned long long)block, nr, flags);
 
@@ -213,6 +242,11 @@ int ocfs2_read_blocks(struct ocfs2_caching_info *ci, u64 block, int nr,
 		goto bail;
 	}
 
+	/* Don't put buffer head and re-assign it to NULL if it is allocated
+	 * outside since the caller can't be aware of this alternation!
+	 */
+	new_bh = (bhs[0] == NULL);
+
 	ocfs2_metadata_cache_io_lock(ci);
 	for (i = 0 ; i < nr ; i++) {
 		if (bhs[i] == NULL) {
@@ -221,7 +255,8 @@ int ocfs2_read_blocks(struct ocfs2_caching_info *ci, u64 block, int nr,
 				ocfs2_metadata_cache_io_unlock(ci);
 				status = -ENOMEM;
 				mlog_errno(status);
-				goto bail;
+				/* Don't forget to put previous bh! */
+				break;
 			}
 		}
 		bh = bhs[i];
@@ -316,16 +351,27 @@ int ocfs2_read_blocks(struct ocfs2_caching_info *ci, u64 block, int nr,
 		}
 	}
 
-	status = 0;
-
+read_failure:
 	for (i = (nr - 1); i >= 0; i--) {
 		bh = bhs[i];
 
 		if (!(flags & OCFS2_BH_READAHEAD)) {
-			if (status) {
-				/* Clear the rest of the buffers on error */
-				put_bh(bh);
-				bhs[i] = NULL;
+			if (unlikely(status)) {
+				/* Clear the buffers on error including those
+				 * ever succeeded in reading
+				 */
+				if (new_bh && bh) {
+					/* If middle bh fails, let previous bh
+					 * finish its read and then put it to
+					 * aovoid bh leak
+					 */
+					if (!buffer_jbd(bh))
+						wait_on_buffer(bh);
+					put_bh(bh);
+					bhs[i] = NULL;
+				} else if (bh && buffer_uptodate(bh)) {
+					clear_buffer_uptodate(bh);
+				}
 				continue;
 			}
 			/* We know this can't have changed as we hold the
@@ -343,9 +389,7 @@ int ocfs2_read_blocks(struct ocfs2_caching_info *ci, u64 block, int nr,
 				 * uptodate. */
 				status = -EIO;
 				clear_buffer_needs_validate(bh);
-				put_bh(bh);
-				bhs[i] = NULL;
-				continue;
+				goto read_failure;
 			}
 
 			if (buffer_needs_validate(bh)) {
@@ -355,11 +399,8 @@ int ocfs2_read_blocks(struct ocfs2_caching_info *ci, u64 block, int nr,
 				BUG_ON(buffer_jbd(bh));
 				clear_buffer_needs_validate(bh);
 				status = validate(sb, bh);
-				if (status) {
-					put_bh(bh);
-					bhs[i] = NULL;
-					continue;
-				}
+				if (status)
+					goto read_failure;
 			}
 		}
 
diff --git a/fs/ocfs2/cluster/tcp.c b/fs/ocfs2/cluster/tcp.c
index 7d9eea7d4a87..e9f236af1927 100644
--- a/fs/ocfs2/cluster/tcp.c
+++ b/fs/ocfs2/cluster/tcp.c
@@ -916,7 +916,7 @@ static int o2net_recv_tcp_msg(struct socket *sock, void *data, size_t len)
 {
 	struct kvec vec = { .iov_len = len, .iov_base = data, };
 	struct msghdr msg = { .msg_flags = MSG_DONTWAIT, };
-	iov_iter_kvec(&msg.msg_iter, READ | ITER_KVEC, &vec, 1, len);
+	iov_iter_kvec(&msg.msg_iter, READ, &vec, 1, len);
 	return sock_recvmsg(sock, &msg, MSG_DONTWAIT);
 }
 
diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c
index b048d4fa3959..c121abbdfc7d 100644
--- a/fs/ocfs2/dir.c
+++ b/fs/ocfs2/dir.c
@@ -1897,8 +1897,7 @@ static int ocfs2_dir_foreach_blk_el(struct inode *inode,
 				/* On error, skip the f_pos to the
 				   next block. */
 				ctx->pos = (ctx->pos | (sb->s_blocksize - 1)) + 1;
-				brelse(bh);
-				continue;
+				break;
 			}
 			if (le64_to_cpu(de->inode)) {
 				unsigned char d_type = DT_UNKNOWN;
diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
index 933aac5da193..7c835824247e 100644
--- a/fs/ocfs2/dlmglue.c
+++ b/fs/ocfs2/dlmglue.c
@@ -2123,10 +2123,10 @@ static void ocfs2_downconvert_on_unlock(struct ocfs2_super *osb,
 
 /* LVB only has room for 64 bits of time here so we pack it for
  * now. */
-static u64 ocfs2_pack_timespec(struct timespec *spec)
+static u64 ocfs2_pack_timespec(struct timespec64 *spec)
 {
 	u64 res;
-	u64 sec = spec->tv_sec;
+	u64 sec = clamp_t(time64_t, spec->tv_sec, 0, 0x3ffffffffull);
 	u32 nsec = spec->tv_nsec;
 
 	res = (sec << OCFS2_SEC_SHIFT) | (nsec & OCFS2_NSEC_MASK);
@@ -2142,7 +2142,6 @@ static void __ocfs2_stuff_meta_lvb(struct inode *inode)
 	struct ocfs2_inode_info *oi = OCFS2_I(inode);
 	struct ocfs2_lock_res *lockres = &oi->ip_inode_lockres;
 	struct ocfs2_meta_lvb *lvb;
-	struct timespec ts;
 
 	lvb = ocfs2_dlm_lvb(&lockres->l_lksb);
 
@@ -2163,15 +2162,12 @@ static void __ocfs2_stuff_meta_lvb(struct inode *inode)
 	lvb->lvb_igid      = cpu_to_be32(i_gid_read(inode));
 	lvb->lvb_imode     = cpu_to_be16(inode->i_mode);
 	lvb->lvb_inlink    = cpu_to_be16(inode->i_nlink);
-	ts = timespec64_to_timespec(inode->i_atime);
 	lvb->lvb_iatime_packed  =
-		cpu_to_be64(ocfs2_pack_timespec(&ts));
-	ts = timespec64_to_timespec(inode->i_ctime);
+		cpu_to_be64(ocfs2_pack_timespec(&inode->i_atime));
 	lvb->lvb_ictime_packed =
-		cpu_to_be64(ocfs2_pack_timespec(&ts));
-	ts = timespec64_to_timespec(inode->i_mtime);
+		cpu_to_be64(ocfs2_pack_timespec(&inode->i_ctime));
 	lvb->lvb_imtime_packed =
-		cpu_to_be64(ocfs2_pack_timespec(&ts));
+		cpu_to_be64(ocfs2_pack_timespec(&inode->i_mtime));
 	lvb->lvb_iattr    = cpu_to_be32(oi->ip_attr);
 	lvb->lvb_idynfeatures = cpu_to_be16(oi->ip_dyn_features);
 	lvb->lvb_igeneration = cpu_to_be32(inode->i_generation);
@@ -2180,7 +2176,7 @@ out:
 	mlog_meta_lvb(0, lockres);
 }
 
-static void ocfs2_unpack_timespec(struct timespec *spec,
+static void ocfs2_unpack_timespec(struct timespec64 *spec,
 				  u64 packed_time)
 {
 	spec->tv_sec = packed_time >> OCFS2_SEC_SHIFT;
@@ -2189,7 +2185,6 @@ static void ocfs2_unpack_timespec(struct timespec *spec,
 
 static void ocfs2_refresh_inode_from_lvb(struct inode *inode)
 {
-	struct timespec ts;
 	struct ocfs2_inode_info *oi = OCFS2_I(inode);
 	struct ocfs2_lock_res *lockres = &oi->ip_inode_lockres;
 	struct ocfs2_meta_lvb *lvb;
@@ -2217,15 +2212,12 @@ static void ocfs2_refresh_inode_from_lvb(struct inode *inode)
 	i_gid_write(inode, be32_to_cpu(lvb->lvb_igid));
 	inode->i_mode    = be16_to_cpu(lvb->lvb_imode);
 	set_nlink(inode, be16_to_cpu(lvb->lvb_inlink));
-	ocfs2_unpack_timespec(&ts,
+	ocfs2_unpack_timespec(&inode->i_atime,
 			      be64_to_cpu(lvb->lvb_iatime_packed));
-	inode->i_atime = timespec_to_timespec64(ts);
-	ocfs2_unpack_timespec(&ts,
+	ocfs2_unpack_timespec(&inode->i_mtime,
 			      be64_to_cpu(lvb->lvb_imtime_packed));
-	inode->i_mtime = timespec_to_timespec64(ts);
-	ocfs2_unpack_timespec(&ts,
+	ocfs2_unpack_timespec(&inode->i_ctime,
 			      be64_to_cpu(lvb->lvb_ictime_packed));
-	inode->i_ctime = timespec_to_timespec64(ts);
 	spin_unlock(&oi->ip_lock);
 }
 
@@ -3603,7 +3595,7 @@ static int ocfs2_downconvert_lock(struct ocfs2_super *osb,
 	 * we can recover correctly from node failure. Otherwise, we may get
 	 * invalid LVB in LKB, but without DLM_SBF_VALNOTVALID being set.
 	 */
-	if (!ocfs2_is_o2cb_active() &&
+	if (ocfs2_userspace_stack(osb) &&
 	    lockres->l_ops->flags & LOCK_TYPE_USES_LVB)
 		lvb = 1;
 
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 9fa35cb6f6e0..d640c5f8a85d 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -2343,7 +2343,7 @@ static ssize_t ocfs2_file_write_iter(struct kiocb *iocb,
 
 	written = __generic_file_write_iter(iocb, from);
 	/* buffered aio wouldn't have proper lock coverage today */
-	BUG_ON(written == -EIOCBQUEUED && !(iocb->ki_flags & IOCB_DIRECT));
+	BUG_ON(written == -EIOCBQUEUED && !direct_io);
 
 	/*
 	 * deep in g_f_a_w_n()->ocfs2_direct_IO we pass in a ocfs2_dio_end_io
@@ -2463,7 +2463,7 @@ static ssize_t ocfs2_file_read_iter(struct kiocb *iocb,
 	trace_generic_file_read_iter_ret(ret);
 
 	/* buffered aio wouldn't have proper lock coverage today */
-	BUG_ON(ret == -EIOCBQUEUED && !(iocb->ki_flags & IOCB_DIRECT));
+	BUG_ON(ret == -EIOCBQUEUED && !direct_io);
 
 	/* see ocfs2_file_write_iter */
 	if (ret == -EIOCBQUEUED || !ocfs2_iocb_is_rw_locked(iocb)) {
@@ -2527,24 +2527,79 @@ out:
 	return offset;
 }
 
-static int ocfs2_file_clone_range(struct file *file_in,
-				  loff_t pos_in,
-				  struct file *file_out,
-				  loff_t pos_out,
-				  u64 len)
+static loff_t ocfs2_remap_file_range(struct file *file_in, loff_t pos_in,
+				     struct file *file_out, loff_t pos_out,
+				     loff_t len, unsigned int remap_flags)
 {
-	return ocfs2_reflink_remap_range(file_in, pos_in, file_out, pos_out,
-					 len, false);
-}
+	struct inode *inode_in = file_inode(file_in);
+	struct inode *inode_out = file_inode(file_out);
+	struct ocfs2_super *osb = OCFS2_SB(inode_in->i_sb);
+	struct buffer_head *in_bh = NULL, *out_bh = NULL;
+	bool same_inode = (inode_in == inode_out);
+	loff_t remapped = 0;
+	ssize_t ret;
 
-static int ocfs2_file_dedupe_range(struct file *file_in,
-				   loff_t pos_in,
-				   struct file *file_out,
-				   loff_t pos_out,
-				   u64 len)
-{
-	return ocfs2_reflink_remap_range(file_in, pos_in, file_out, pos_out,
-					  len, true);
+	if (remap_flags & ~(REMAP_FILE_DEDUP | REMAP_FILE_ADVISORY))
+		return -EINVAL;
+	if (!ocfs2_refcount_tree(osb))
+		return -EOPNOTSUPP;
+	if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
+		return -EROFS;
+
+	/* Lock both files against IO */
+	ret = ocfs2_reflink_inodes_lock(inode_in, &in_bh, inode_out, &out_bh);
+	if (ret)
+		return ret;
+
+	/* Check file eligibility and prepare for block sharing. */
+	ret = -EINVAL;
+	if ((OCFS2_I(inode_in)->ip_flags & OCFS2_INODE_SYSTEM_FILE) ||
+	    (OCFS2_I(inode_out)->ip_flags & OCFS2_INODE_SYSTEM_FILE))
+		goto out_unlock;
+
+	ret = generic_remap_file_range_prep(file_in, pos_in, file_out, pos_out,
+			&len, remap_flags);
+	if (ret < 0 || len == 0)
+		goto out_unlock;
+
+	/* Lock out changes to the allocation maps and remap. */
+	down_write(&OCFS2_I(inode_in)->ip_alloc_sem);
+	if (!same_inode)
+		down_write_nested(&OCFS2_I(inode_out)->ip_alloc_sem,
+				  SINGLE_DEPTH_NESTING);
+
+	/* Zap any page cache for the destination file's range. */
+	truncate_inode_pages_range(&inode_out->i_data,
+				   round_down(pos_out, PAGE_SIZE),
+				   round_up(pos_out + len, PAGE_SIZE) - 1);
+
+	remapped = ocfs2_reflink_remap_blocks(inode_in, in_bh, pos_in,
+			inode_out, out_bh, pos_out, len);
+	up_write(&OCFS2_I(inode_in)->ip_alloc_sem);
+	if (!same_inode)
+		up_write(&OCFS2_I(inode_out)->ip_alloc_sem);
+	if (remapped < 0) {
+		ret = remapped;
+		mlog_errno(ret);
+		goto out_unlock;
+	}
+
+	/*
+	 * Empty the extent map so that we may get the right extent
+	 * record from the disk.
+	 */
+	ocfs2_extent_map_trunc(inode_in, 0);
+	ocfs2_extent_map_trunc(inode_out, 0);
+
+	ret = ocfs2_reflink_update_dest(inode_out, out_bh, pos_out + len);
+	if (ret) {
+		mlog_errno(ret);
+		goto out_unlock;
+	}
+
+out_unlock:
+	ocfs2_reflink_inodes_unlock(inode_in, in_bh, inode_out, out_bh);
+	return remapped > 0 ? remapped : ret;
 }
 
 const struct inode_operations ocfs2_file_iops = {
@@ -2586,8 +2641,7 @@ const struct file_operations ocfs2_fops = {
 	.splice_read	= generic_file_splice_read,
 	.splice_write	= iter_file_splice_write,
 	.fallocate	= ocfs2_fallocate,
-	.clone_file_range = ocfs2_file_clone_range,
-	.dedupe_file_range = ocfs2_file_dedupe_range,
+	.remap_file_range = ocfs2_remap_file_range,
 };
 
 const struct file_operations ocfs2_dops = {
@@ -2633,8 +2687,7 @@ const struct file_operations ocfs2_fops_no_plocks = {
 	.splice_read	= generic_file_splice_read,
 	.splice_write	= iter_file_splice_write,
 	.fallocate	= ocfs2_fallocate,
-	.clone_file_range = ocfs2_file_clone_range,
-	.dedupe_file_range = ocfs2_file_dedupe_range,
+	.remap_file_range = ocfs2_remap_file_range,
 };
 
 const struct file_operations ocfs2_dops_no_plocks = {
diff --git a/fs/ocfs2/journal.c b/fs/ocfs2/journal.c
index bd3475694e83..b63c97f4318e 100644
--- a/fs/ocfs2/journal.c
+++ b/fs/ocfs2/journal.c
@@ -1378,15 +1378,23 @@ static int __ocfs2_recovery_thread(void *arg)
 	int rm_quota_used = 0, i;
 	struct ocfs2_quota_recovery *qrec;
 
+	/* Whether the quota supported. */
+	int quota_enabled = OCFS2_HAS_RO_COMPAT_FEATURE(osb->sb,
+			OCFS2_FEATURE_RO_COMPAT_USRQUOTA)
+		|| OCFS2_HAS_RO_COMPAT_FEATURE(osb->sb,
+			OCFS2_FEATURE_RO_COMPAT_GRPQUOTA);
+
 	status = ocfs2_wait_on_mount(osb);
 	if (status < 0) {
 		goto bail;
 	}
 
-	rm_quota = kcalloc(osb->max_slots, sizeof(int), GFP_NOFS);
-	if (!rm_quota) {
-		status = -ENOMEM;
-		goto bail;
+	if (quota_enabled) {
+		rm_quota = kcalloc(osb->max_slots, sizeof(int), GFP_NOFS);
+		if (!rm_quota) {
+			status = -ENOMEM;
+			goto bail;
+		}
 	}
 restart:
 	status = ocfs2_super_lock(osb, 1);
@@ -1422,9 +1430,14 @@ restart:
 		 * then quota usage would be out of sync until some node takes
 		 * the slot. So we remember which nodes need quota recovery
 		 * and when everything else is done, we recover quotas. */
-		for (i = 0; i < rm_quota_used && rm_quota[i] != slot_num; i++);
-		if (i == rm_quota_used)
-			rm_quota[rm_quota_used++] = slot_num;
+		if (quota_enabled) {
+			for (i = 0; i < rm_quota_used
+					&& rm_quota[i] != slot_num; i++)
+				;
+
+			if (i == rm_quota_used)
+				rm_quota[rm_quota_used++] = slot_num;
+		}
 
 		status = ocfs2_recover_node(osb, node_num, slot_num);
 skip_recovery:
@@ -1452,16 +1465,19 @@ skip_recovery:
 	/* Now it is right time to recover quotas... We have to do this under
 	 * superblock lock so that no one can start using the slot (and crash)
 	 * before we recover it */
-	for (i = 0; i < rm_quota_used; i++) {
-		qrec = ocfs2_begin_quota_recovery(osb, rm_quota[i]);
-		if (IS_ERR(qrec)) {
-			status = PTR_ERR(qrec);
-			mlog_errno(status);
-			continue;
+	if (quota_enabled) {
+		for (i = 0; i < rm_quota_used; i++) {
+			qrec = ocfs2_begin_quota_recovery(osb, rm_quota[i]);
+			if (IS_ERR(qrec)) {
+				status = PTR_ERR(qrec);
+				mlog_errno(status);
+				continue;
+			}
+			ocfs2_queue_recovery_completion(osb->journal,
+					rm_quota[i],
+					NULL, NULL, qrec,
+					ORPHAN_NEED_TRUNCATE);
 		}
-		ocfs2_queue_recovery_completion(osb->journal, rm_quota[i],
-						NULL, NULL, qrec,
-						ORPHAN_NEED_TRUNCATE);
 	}
 
 	ocfs2_super_unlock(osb, 1);
@@ -1483,7 +1499,8 @@ bail:
 
 	mutex_unlock(&osb->recovery_lock);
 
-	kfree(rm_quota);
+	if (quota_enabled)
+		kfree(rm_quota);
 
 	/* no one is callint kthread_stop() for us so the kthread() api
 	 * requires that we call do_exit().  And it isn't exported, but
diff --git a/fs/ocfs2/move_extents.c b/fs/ocfs2/move_extents.c
index 7eb3b0a6347e..3f1685d7d43b 100644
--- a/fs/ocfs2/move_extents.c
+++ b/fs/ocfs2/move_extents.c
@@ -25,6 +25,7 @@
 #include "ocfs2_ioctl.h"
 
 #include "alloc.h"
+#include "localalloc.h"
 #include "aops.h"
 #include "dlmglue.h"
 #include "extent_map.h"
@@ -233,6 +234,7 @@ static int ocfs2_defrag_extent(struct ocfs2_move_extents_context *context,
 	struct ocfs2_refcount_tree *ref_tree = NULL;
 	u32 new_phys_cpos, new_len;
 	u64 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
+	int need_free = 0;
 
 	if ((ext_flags & OCFS2_EXT_REFCOUNTED) && *len) {
 		BUG_ON(!ocfs2_is_refcount_inode(inode));
@@ -308,6 +310,7 @@ static int ocfs2_defrag_extent(struct ocfs2_move_extents_context *context,
 		if (!partial) {
 			context->range->me_flags &= ~OCFS2_MOVE_EXT_FL_COMPLETE;
 			ret = -ENOSPC;
+			need_free = 1;
 			goto out_commit;
 		}
 	}
@@ -332,6 +335,20 @@ static int ocfs2_defrag_extent(struct ocfs2_move_extents_context *context,
 		mlog_errno(ret);
 
 out_commit:
+	if (need_free && context->data_ac) {
+		struct ocfs2_alloc_context *data_ac = context->data_ac;
+
+		if (context->data_ac->ac_which == OCFS2_AC_USE_LOCAL)
+			ocfs2_free_local_alloc_bits(osb, handle, data_ac,
+					new_phys_cpos, new_len);
+		else
+			ocfs2_free_clusters(handle,
+					data_ac->ac_inode,
+					data_ac->ac_bh,
+					ocfs2_clusters_to_blocks(osb->sb, new_phys_cpos),
+					new_len);
+	}
+
 	ocfs2_commit_trans(osb, handle);
 
 out_unlock_mutex:
diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
index 1114ef02e780..a35259eebc56 100644
--- a/fs/ocfs2/refcounttree.c
+++ b/fs/ocfs2/refcounttree.c
@@ -4466,9 +4466,9 @@ out:
 }
 
 /* Update destination inode size, if necessary. */
-static int ocfs2_reflink_update_dest(struct inode *dest,
-				     struct buffer_head *d_bh,
-				     loff_t newlen)
+int ocfs2_reflink_update_dest(struct inode *dest,
+			      struct buffer_head *d_bh,
+			      loff_t newlen)
 {
 	handle_t *handle;
 	int ret;
@@ -4505,14 +4505,14 @@ out_commit:
 }
 
 /* Remap the range pos_in:len in s_inode to pos_out:len in t_inode. */
-static int ocfs2_reflink_remap_extent(struct inode *s_inode,
-				      struct buffer_head *s_bh,
-				      loff_t pos_in,
-				      struct inode *t_inode,
-				      struct buffer_head *t_bh,
-				      loff_t pos_out,
-				      loff_t len,
-				      struct ocfs2_cached_dealloc_ctxt *dealloc)
+static loff_t ocfs2_reflink_remap_extent(struct inode *s_inode,
+					 struct buffer_head *s_bh,
+					 loff_t pos_in,
+					 struct inode *t_inode,
+					 struct buffer_head *t_bh,
+					 loff_t pos_out,
+					 loff_t len,
+					 struct ocfs2_cached_dealloc_ctxt *dealloc)
 {
 	struct ocfs2_extent_tree s_et;
 	struct ocfs2_extent_tree t_et;
@@ -4520,8 +4520,9 @@ static int ocfs2_reflink_remap_extent(struct inode *s_inode,
 	struct buffer_head *ref_root_bh = NULL;
 	struct ocfs2_refcount_tree *ref_tree;
 	struct ocfs2_super *osb;
+	loff_t remapped_bytes = 0;
 	loff_t pstart, plen;
-	u32 p_cluster, num_clusters, slast, spos, tpos;
+	u32 p_cluster, num_clusters, slast, spos, tpos, remapped_clus = 0;
 	unsigned int ext_flags;
 	int ret = 0;
 
@@ -4603,30 +4604,34 @@ static int ocfs2_reflink_remap_extent(struct inode *s_inode,
 next_loop:
 		spos += num_clusters;
 		tpos += num_clusters;
+		remapped_clus += num_clusters;
 	}
 
-out:
-	return ret;
+	goto out;
 out_unlock_refcount:
 	ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
 	brelse(ref_root_bh);
-	return ret;
+out:
+	remapped_bytes = ocfs2_clusters_to_bytes(t_inode->i_sb, remapped_clus);
+	remapped_bytes = min_t(loff_t, len, remapped_bytes);
+
+	return remapped_bytes > 0 ? remapped_bytes : ret;
 }
 
 /* Set up refcount tree and remap s_inode to t_inode. */
-static int ocfs2_reflink_remap_blocks(struct inode *s_inode,
-				      struct buffer_head *s_bh,
-				      loff_t pos_in,
-				      struct inode *t_inode,
-				      struct buffer_head *t_bh,
-				      loff_t pos_out,
-				      loff_t len)
+loff_t ocfs2_reflink_remap_blocks(struct inode *s_inode,
+				  struct buffer_head *s_bh,
+				  loff_t pos_in,
+				  struct inode *t_inode,
+				  struct buffer_head *t_bh,
+				  loff_t pos_out,
+				  loff_t len)
 {
 	struct ocfs2_cached_dealloc_ctxt dealloc;
 	struct ocfs2_super *osb;
 	struct ocfs2_dinode *dis;
 	struct ocfs2_dinode *dit;
-	int ret;
+	loff_t ret;
 
 	osb = OCFS2_SB(s_inode->i_sb);
 	dis = (struct ocfs2_dinode *)s_bh->b_data;
@@ -4698,7 +4703,7 @@ static int ocfs2_reflink_remap_blocks(struct inode *s_inode,
 	/* Actually remap extents now. */
 	ret = ocfs2_reflink_remap_extent(s_inode, s_bh, pos_in, t_inode, t_bh,
 					 pos_out, len, &dealloc);
-	if (ret) {
+	if (ret < 0) {
 		mlog_errno(ret);
 		goto out;
 	}
@@ -4713,10 +4718,10 @@ out:
 }
 
 /* Lock an inode and grab a bh pointing to the inode. */
-static int ocfs2_reflink_inodes_lock(struct inode *s_inode,
-				     struct buffer_head **bh1,
-				     struct inode *t_inode,
-				     struct buffer_head **bh2)
+int ocfs2_reflink_inodes_lock(struct inode *s_inode,
+			      struct buffer_head **bh1,
+			      struct inode *t_inode,
+			      struct buffer_head **bh2)
 {
 	struct inode *inode1;
 	struct inode *inode2;
@@ -4801,10 +4806,10 @@ out_i1:
 }
 
 /* Unlock both inodes and release buffers. */
-static void ocfs2_reflink_inodes_unlock(struct inode *s_inode,
-					struct buffer_head *s_bh,
-					struct inode *t_inode,
-					struct buffer_head *t_bh)
+void ocfs2_reflink_inodes_unlock(struct inode *s_inode,
+				 struct buffer_head *s_bh,
+				 struct inode *t_inode,
+				 struct buffer_head *t_bh)
 {
 	ocfs2_inode_unlock(s_inode, 1);
 	ocfs2_rw_unlock(s_inode, 1);
@@ -4816,82 +4821,3 @@ static void ocfs2_reflink_inodes_unlock(struct inode *s_inode,
 	}
 	unlock_two_nondirectories(s_inode, t_inode);
 }
-
-/* Link a range of blocks from one file to another. */
-int ocfs2_reflink_remap_range(struct file *file_in,
-			      loff_t pos_in,
-			      struct file *file_out,
-			      loff_t pos_out,
-			      u64 len,
-			      bool is_dedupe)
-{
-	struct inode *inode_in = file_inode(file_in);
-	struct inode *inode_out = file_inode(file_out);
-	struct ocfs2_super *osb = OCFS2_SB(inode_in->i_sb);
-	struct buffer_head *in_bh = NULL, *out_bh = NULL;
-	bool same_inode = (inode_in == inode_out);
-	ssize_t ret;
-
-	if (!ocfs2_refcount_tree(osb))
-		return -EOPNOTSUPP;
-	if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
-		return -EROFS;
-
-	/* Lock both files against IO */
-	ret = ocfs2_reflink_inodes_lock(inode_in, &in_bh, inode_out, &out_bh);
-	if (ret)
-		return ret;
-
-	/* Check file eligibility and prepare for block sharing. */
-	ret = -EINVAL;
-	if ((OCFS2_I(inode_in)->ip_flags & OCFS2_INODE_SYSTEM_FILE) ||
-	    (OCFS2_I(inode_out)->ip_flags & OCFS2_INODE_SYSTEM_FILE))
-		goto out_unlock;
-
-	ret = vfs_clone_file_prep_inodes(inode_in, pos_in, inode_out, pos_out,
-			&len, is_dedupe);
-	if (ret <= 0)
-		goto out_unlock;
-
-	/* Lock out changes to the allocation maps and remap. */
-	down_write(&OCFS2_I(inode_in)->ip_alloc_sem);
-	if (!same_inode)
-		down_write_nested(&OCFS2_I(inode_out)->ip_alloc_sem,
-				  SINGLE_DEPTH_NESTING);
-
-	ret = ocfs2_reflink_remap_blocks(inode_in, in_bh, pos_in, inode_out,
-					 out_bh, pos_out, len);
-
-	/* Zap any page cache for the destination file's range. */
-	if (!ret)
-		truncate_inode_pages_range(&inode_out->i_data, pos_out,
-					   PAGE_ALIGN(pos_out + len) - 1);
-
-	up_write(&OCFS2_I(inode_in)->ip_alloc_sem);
-	if (!same_inode)
-		up_write(&OCFS2_I(inode_out)->ip_alloc_sem);
-	if (ret) {
-		mlog_errno(ret);
-		goto out_unlock;
-	}
-
-	/*
-	 * Empty the extent map so that we may get the right extent
-	 * record from the disk.
-	 */
-	ocfs2_extent_map_trunc(inode_in, 0);
-	ocfs2_extent_map_trunc(inode_out, 0);
-
-	ret = ocfs2_reflink_update_dest(inode_out, out_bh, pos_out + len);
-	if (ret) {
-		mlog_errno(ret);
-		goto out_unlock;
-	}
-
-	ocfs2_reflink_inodes_unlock(inode_in, in_bh, inode_out, out_bh);
-	return 0;
-
-out_unlock:
-	ocfs2_reflink_inodes_unlock(inode_in, in_bh, inode_out, out_bh);
-	return ret;
-}
diff --git a/fs/ocfs2/refcounttree.h b/fs/ocfs2/refcounttree.h
index 4af55bf4b35b..e9e862be4a1e 100644
--- a/fs/ocfs2/refcounttree.h
+++ b/fs/ocfs2/refcounttree.h
@@ -115,11 +115,23 @@ int ocfs2_reflink_ioctl(struct inode *inode,
 			const char __user *oldname,
 			const char __user *newname,
 			bool preserve);
-int ocfs2_reflink_remap_range(struct file *file_in,
-			      loff_t pos_in,
-			      struct file *file_out,
-			      loff_t pos_out,
-			      u64 len,
-			      bool is_dedupe);
+loff_t ocfs2_reflink_remap_blocks(struct inode *s_inode,
+				  struct buffer_head *s_bh,
+				  loff_t pos_in,
+				  struct inode *t_inode,
+				  struct buffer_head *t_bh,
+				  loff_t pos_out,
+				  loff_t len);
+int ocfs2_reflink_inodes_lock(struct inode *s_inode,
+			      struct buffer_head **bh1,
+			      struct inode *t_inode,
+			      struct buffer_head **bh2);
+void ocfs2_reflink_inodes_unlock(struct inode *s_inode,
+				 struct buffer_head *s_bh,
+				 struct inode *t_inode,
+				 struct buffer_head *t_bh);
+int ocfs2_reflink_update_dest(struct inode *dest,
+			      struct buffer_head *d_bh,
+			      loff_t newlen);
 
 #endif /* OCFS2_REFCOUNTTREE_H */
diff --git a/fs/ocfs2/stackglue.c b/fs/ocfs2/stackglue.c
index d6c350ba25b9..c4b029c43464 100644
--- a/fs/ocfs2/stackglue.c
+++ b/fs/ocfs2/stackglue.c
@@ -48,12 +48,6 @@ static char ocfs2_hb_ctl_path[OCFS2_MAX_HB_CTL_PATH] = "/sbin/ocfs2_hb_ctl";
  */
 static struct ocfs2_stack_plugin *active_stack;
 
-inline int ocfs2_is_o2cb_active(void)
-{
-	return !strcmp(active_stack->sp_name, OCFS2_STACK_PLUGIN_O2CB);
-}
-EXPORT_SYMBOL_GPL(ocfs2_is_o2cb_active);
-
 static struct ocfs2_stack_plugin *ocfs2_stack_lookup(const char *name)
 {
 	struct ocfs2_stack_plugin *p;
diff --git a/fs/ocfs2/stackglue.h b/fs/ocfs2/stackglue.h
index e3036e1790e8..f2dce10fae54 100644
--- a/fs/ocfs2/stackglue.h
+++ b/fs/ocfs2/stackglue.h
@@ -298,9 +298,6 @@ void ocfs2_stack_glue_set_max_proto_version(struct ocfs2_protocol_version *max_p
 int ocfs2_stack_glue_register(struct ocfs2_stack_plugin *plugin);
 void ocfs2_stack_glue_unregister(struct ocfs2_stack_plugin *plugin);
 
-/* In ocfs2_downconvert_lock(), we need to know which stack we are using */
-int ocfs2_is_o2cb_active(void);
-
 extern struct kset *ocfs2_kset;
 
 #endif  /* STACKGLUE_H */