1 files changed, 26 insertions, 8 deletions

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 6225433..3351b1b 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -859,8 +859,8 @@ again:
 	/* step one, lock all the pages */
 	for (i = 0; i < num_pages; i++) {
 		struct page *page;
-		page = grab_cache_page(inode->i_mapping,
-					    start_index + i);
+		page = find_or_create_page(inode->i_mapping,
+					    start_index + i, GFP_NOFS);
 		if (!page)
 			break;
 
@@ -930,7 +930,9 @@ again:
 			  GFP_NOFS);
 
 	if (i_done != num_pages) {
-		atomic_inc(&BTRFS_I(inode)->outstanding_extents);
+		spin_lock(&BTRFS_I(inode)->lock);
+		BTRFS_I(inode)->outstanding_extents++;
+		spin_unlock(&BTRFS_I(inode)->lock);
 		btrfs_delalloc_release_space(inode,
 				     (num_pages - i_done) << PAGE_CACHE_SHIFT);
 	}
@@ -1747,11 +1749,10 @@ static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
 		key.objectid = key.offset;
 		key.offset = (u64)-1;
 		dirid = key.objectid;
-
 	}
 	if (ptr < name)
 		goto out;
-	memcpy(name, ptr, total_len);
+	memmove(name, ptr, total_len);
 	name[total_len]='\0';
 	ret = 0;
 out:
@@ -2219,6 +2220,12 @@ static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
 	    !IS_ALIGNED(destoff, bs))
 		goto out_unlock;
 
+	if (destoff > inode->i_size) {
+		ret = btrfs_cont_expand(inode, inode->i_size, destoff);
+		if (ret)
+			goto out_unlock;
+	}
+
 	/* do any pending delalloc/csum calc on src, one way or
 	   another, and lock file content */
 	while (1) {
@@ -2235,6 +2242,10 @@ static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
 		btrfs_wait_ordered_range(src, off, len);
 	}
 
+	/* truncate page cache pages from target inode range */
+	truncate_inode_pages_range(&inode->i_data, off,
+				   ALIGN(off + len, PAGE_CACHE_SIZE) - 1);
+
 	/* clone data */
 	key.objectid = btrfs_ino(src);
 	key.type = BTRFS_EXTENT_DATA_KEY;
@@ -2320,14 +2331,21 @@ static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
 
 			if (type == BTRFS_FILE_EXTENT_REG ||
 			    type == BTRFS_FILE_EXTENT_PREALLOC) {
+				/*
+				 *    a  | --- range to clone ---|  b
+				 * | ------------- extent ------------- |
+				 */
+
+				/* substract range b */
+				if (key.offset + datal > off + len)
+					datal = off + len - key.offset;
+
+				/* substract range a */
 				if (off > key.offset) {
 					datao += off - key.offset;
 					datal -= off - key.offset;
 				}
 
-				if (key.offset + datal > off + len)
-					datal = off + len - key.offset;
-
 				ret = btrfs_drop_extents(trans, inode,
 							 new_key.offset,
 							 new_key.offset + datal,