Jan Kara <jack@xxxxxxx> writes: > When we do delayed allocation of some buffer, we want to signal to VFS that > the buffer is new (set buffer_new) so that it properly zeros out everything. > But we don't have the buffer mapped yet so we cannot really unmap underlying > metadata in this state. Make VFS avoid doing unmapping of metadata when the > buffer is not yet mapped. I may be missing something. However, isn't the delalloc buffer == (buffer_mapped() | buffer_delay())? Well, anyway, if buffer is not buffer_mapped(), e.g. truncate() works properly? Thanks. > diff --git a/fs/buffer.c b/fs/buffer.c > index 80e2630..7eb1710 100644 > --- a/fs/buffer.c > +++ b/fs/buffer.c > @@ -1683,8 +1683,9 @@ static int __block_write_full_page(struct inode *inode, struct page *page, > if (buffer_new(bh)) { > /* blockdev mappings never come here */ > clear_buffer_new(bh); > - unmap_underlying_metadata(bh->b_bdev, > - bh->b_blocknr); > + if (buffer_mapped(bh)) > + unmap_underlying_metadata(bh->b_bdev, > + bh->b_blocknr); Is this needed for writepage? > } > } > bh = bh->b_this_page; -- OGAWA Hirofumi <hirofumi@xxxxxxxxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html