Btrfs: Allow tails larger than one page

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 20 insertions, 12 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index d6b3a55ed8e0..84f496c838c9 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -87,7 +87,7 @@ static int run_delalloc_range(struct inode *inode, u64 start, u64 end)
         BUG_ON(!trans);
         num_bytes = (end - start + blocksize) & ~(blocksize - 1);
         ret = btrfs_drop_extents(trans, root, inode,
-                                 start, start + num_bytes, &alloc_hint);
+                                 start, start + num_bytes, start, &alloc_hint);
 
         ret = btrfs_alloc_extent(trans, root, inode->i_ino, num_bytes, 0,
                                  alloc_hint, (u64)-1, &ins, 1);
@@ -776,7 +776,8 @@ static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
                 trans = btrfs_start_transaction(root, 1);
                 btrfs_set_trans_block_group(trans, inode);
                 err = btrfs_drop_extents(trans, root, inode,
-                                         pos, pos + hole_size, &alloc_hint);
+                                         pos, pos + hole_size, pos,
+                                         &alloc_hint);
 
                 err = btrfs_insert_file_extent(trans, root, inode->i_ino,
                                                pos, 0, 0, hole_size);
@@ -1581,7 +1582,9 @@ again:
         } else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
                 unsigned long ptr;
                 char *map;
-                u32 size;
+                size_t size;
+                size_t extent_offset;
+                size_t copy_size;
 
                 size = btrfs_file_extent_inline_len(leaf, btrfs_item_nr(leaf,
                                                     path->slots[0]));
@@ -1600,26 +1603,31 @@ again:
                         goto not_found_em;
                 }
 
+                extent_offset = (page->index << PAGE_CACHE_SHIFT) -
+                        extent_start;
+                ptr = btrfs_file_extent_inline_start(item) + extent_offset;
+                map = kmap(page);
+                copy_size = min(PAGE_CACHE_SIZE - page_offset,
+                                size - extent_offset);
+
                 em->block_start = EXTENT_MAP_INLINE;
                 em->block_end = EXTENT_MAP_INLINE;
-                em->start = extent_start;
-                em->end = extent_end;
+                em->start = extent_start + extent_offset;
+                em->end = (em->start + copy_size -1) |
+                        ((u64)root->sectorsize -1);
 
                 if (!page) {
                         goto insert;
                 }
 
-                ptr = btrfs_file_extent_inline_start(item);
-                map = kmap(page);
-                read_extent_buffer(leaf, map + page_offset, ptr, size);
+                read_extent_buffer(leaf, map + page_offset, ptr, copy_size);
                 /*
-                memset(map + page_offset + size, 0,
-                       root->sectorsize - (page_offset + size));
+                memset(map + page_offset + copy_size, 0,
+                       PAGE_CACHE_SIZE - copy_size - page_offset);
                        */
                 flush_dcache_page(page);
                 kunmap(page);
-                set_extent_uptodate(em_tree, extent_start,
-                                    extent_end, GFP_NOFS);
+                set_extent_uptodate(em_tree, em->start, em->end, GFP_NOFS);
                 goto insert;
         } else {
                 printk("unkknown found_type %d\n", found_type);