1 files changed, 35 insertions, 24 deletions

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 03bb62a9ee24..d8b54715c2de 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -861,6 +861,7 @@ static int cluster_pages_for_defrag(struct inode *inode,
         int i_done;
         struct btrfs_ordered_extent *ordered;
         struct extent_state *cached_state = NULL;
+        struct extent_io_tree *tree;
         gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
 
         if (isize == 0)
@@ -871,18 +872,34 @@ static int cluster_pages_for_defrag(struct inode *inode,
                                            num_pages << PAGE_CACHE_SHIFT);
         if (ret)
                 return ret;
-again:
-        ret = 0;
         i_done = 0;
+        tree = &BTRFS_I(inode)->io_tree;
 
         /* step one, lock all the pages */
         for (i = 0; i < num_pages; i++) {
                 struct page *page;
+again:
                 page = find_or_create_page(inode->i_mapping,
-                                            start_index + i, mask);
+                                           start_index + i, mask);
                 if (!page)
                         break;
 
+                page_start = page_offset(page);
+                page_end = page_start + PAGE_CACHE_SIZE - 1;
+                while (1) {
+                        lock_extent(tree, page_start, page_end, GFP_NOFS);
+                        ordered = btrfs_lookup_ordered_extent(inode,
+                                                              page_start);
+                        unlock_extent(tree, page_start, page_end, GFP_NOFS);
+                        if (!ordered)
+                                break;
+
+                        unlock_page(page);
+                        btrfs_start_ordered_extent(inode, ordered, 1);
+                        btrfs_put_ordered_extent(ordered);
+                        lock_page(page);
+                }
+
                 if (!PageUptodate(page)) {
                         btrfs_readpage(NULL, page);
                         lock_page(page);
@@ -893,15 +910,22 @@ again:
                                 break;
                         }
                 }
+
                 isize = i_size_read(inode);
                 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
-                if (!isize || page->index > file_end ||
-                    page->mapping != inode->i_mapping) {
+                if (!isize || page->index > file_end) {
                         /* whoops, we blew past eof, skip this page */
                         unlock_page(page);
                         page_cache_release(page);
                         break;
                 }
+
+                if (page->mapping != inode->i_mapping) {
+                        unlock_page(page);
+                        page_cache_release(page);
+                        goto again;
+                }
+
                 pages[i] = page;
                 i_done++;
         }
@@ -924,25 +948,6 @@ again:
         lock_extent_bits(&BTRFS_I(inode)->io_tree,
                          page_start, page_end - 1, 0, &cached_state,
                          GFP_NOFS);
-        ordered = btrfs_lookup_first_ordered_extent(inode, page_end - 1);
-        if (ordered &&
-            ordered->file_offset + ordered->len > page_start &&
-            ordered->file_offset < page_end) {
-                btrfs_put_ordered_extent(ordered);
-                unlock_extent_cached(&BTRFS_I(inode)->io_tree,
-                                     page_start, page_end - 1,
-                                     &cached_state, GFP_NOFS);
-                for (i = 0; i < i_done; i++) {
-                        unlock_page(pages[i]);
-                        page_cache_release(pages[i]);
-                }
-                btrfs_wait_ordered_range(inode, page_start,
-                                         page_end - page_start);
-                goto again;
-        }
-        if (ordered)
-                btrfs_put_ordered_extent(ordered);
-
         clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
                           page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
                           EXTENT_DO_ACCOUNTING, 0, 0, &cached_state,
@@ -1327,6 +1332,12 @@ static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
                 goto out;
         }
 
+        if (name[0] == '.' &&
+           (namelen == 1 || (name[1] == '.' && namelen == 2))) {
+                ret = -EEXIST;
+                goto out;
+        }
+
         if (subvol) {
                 ret = btrfs_mksubvol(&file->f_path, name, namelen,
                                      NULL, transid, readonly);