Btrfs: Add O_DIRECT read and write (writes == buffered + cache flush)

[karo-tx-linux.git] / fs / btrfs / file.c

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 5fa450452f9b70a9383081e3656619eec6805226..5b9386452218614ad1ee669818fb5149f7390916 100644 (file)
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -796,8 +796,6 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
                     PAGE_CACHE_SIZE / (sizeof(struct page *)));
        pinned[0] = NULL;
        pinned[1] = NULL;
-       if (file->f_flags & O_DIRECT)
-               return -EINVAL;
 
        pos = *ppos;
        start_pos = pos;
@@ -909,6 +907,15 @@ out_nolock:
                                      start_pos, num_written);
                if (err < 0)
                        num_written = err;
+       } else if (num_written > 0 && (file->f_flags & O_DIRECT)) {
+               do_sync_mapping_range(inode->i_mapping, start_pos,
+                                     start_pos + num_written - 1,
+                                     SYNC_FILE_RANGE_WRITE |
+                                     SYNC_FILE_RANGE_WAIT_AFTER);
+
+               invalidate_mapping_pages(inode->i_mapping,
+                     start_pos >> PAGE_CACHE_SHIFT,
+                    (start_pos + num_written - 1) >> PAGE_CACHE_SHIFT);
        }
        current->backing_dev_info = NULL;
        return num_written ? num_written : err;