From: Kent Overstreet Date: Tue, 15 Aug 2023 02:29:41 +0000 (-0400) Subject: bcachefs: Fix swallowing of data in buffered write path X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=62898dd12ba017c56c39a74ef891845118b0c190;p=linux.git bcachefs: Fix swallowing of data in buffered write path In __bch2_buffered_write, if we fail to write to an entire !uptodate folio, we have to back out the write, bail out and retry. But we were missing an iov_iter_revert() call, so the data written to the folio was lost and the rest of the write shifted to the wrong offset. Signed-off-by: Kent Overstreet --- diff --git a/fs/bcachefs/fs-io-buffered.c b/fs/bcachefs/fs-io-buffered.c index 102c70887f76b..dc22182d532fe 100644 --- a/fs/bcachefs/fs-io-buffered.c +++ b/fs/bcachefs/fs-io-buffered.c @@ -909,6 +909,7 @@ static int __bch2_buffered_write(struct bch_inode_info *inode, if (!folio_test_uptodate(f) && f_copied != folio_size(f) && pos + copied + f_copied < inode->v.i_size) { + iov_iter_revert(iter, f_copied); folio_zero_range(f, 0, folio_size(f)); folios_trunc(&folios, fi); break;