From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Layton Subject: [PATCH v2 0/9] mm/fs: get PG_error out of the writeback reporting business Date: Wed, 8 Mar 2017 11:29:25 -0500 Message-ID: <20170308162934.21989-1-jlayton@redhat.com> Return-path: Sender: owner-linux-mm@kvack.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: viro@zeniv.linux.org.uk, akpm@linux-foundation.org Cc: konishi.ryusuke@lab.ntt.co.jp, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-nilfs@vger.kernel.org, ross.zwisler@linux.intel.com, jack@suse.cz, neilb@suse.com, openosd@gmail.com, adilger@dilger.ca, James.Bottomley@HansenPartnership.com v2: - still ClearPageError during __filemap_fdatawait_range - clear AS_* errors when reporting errors during write initiation - set mapping errors when launder_page fails - set mapping errors when writeback fails during migration - set mapping errors when DAX writeback fails - Documentation patch to give guidance about writeback errors Here is v2 of this set. The main difference is some new patches to ensure that mapping errors get set in a few rather obscure places when writeback fails, and a patch (based on Jan's suggestion) to clear out the address space errors when initiating writeback fails with -EIO. I also left the code clearing PG_error in __filemap_fdatawait_range. We may want to remove that eventually, but we need to ensure that it gets cleared in some way when writeback fails. I've done a bit of testing with this (mostly xfstests on xfs), and it seems to work ok AFAICT. Original cover letter follows: ------------------------------8<----------------------------- I recently did some work to wire up -ENOSPC handling in ceph, and found I could get back -EIO errors in some cases when I should have instead gotten -ENOSPC. The problem was that the ceph writeback code would set PG_error on a writeback error, and that error would clobber the mapping error. While I fixed that problem by simply not setting that bit on errors, that led me down a rabbit hole of looking at how PG_error is being handled in the kernel. This patch series is a few fixes for things that I 100% noticed by inspection. I don't have a great way to test these since they involve error handling. I can certainly doctor up a kernel to inject errors in this code and test by hand however if these look plausible up front. Jeff Layton (9): mm: fix mapping_set_error call in me_pagecache_dirty mm: drop "wait" parameter from write_one_page mm: clear any AS_* errors when returning error on any fsync or close nilfs2: set the mapping error when calling SetPageError on writeback dax: set error in mapping when writeback fails mm: set mapping error when launder_pages fails mm: ensure that we set mapping error if writeout() fails mm: don't TestClearPageError in __filemap_fdatawait_range Documentation: document what to do on a writeback error Documentation/filesystems/vfs.txt | 7 +++++++ fs/dax.c | 4 +++- fs/exofs/dir.c | 2 +- fs/ext2/dir.c | 2 +- fs/jfs/jfs_metapage.c | 4 ++-- fs/minix/dir.c | 2 +- fs/nilfs2/segment.c | 1 + fs/sysv/dir.c | 2 +- fs/ufs/dir.c | 2 +- include/linux/mm.h | 2 +- mm/filemap.c | 40 ++++++++++++++++++++++----------------- mm/memory-failure.c | 2 +- mm/migrate.c | 6 +++++- mm/page-writeback.c | 14 +++++++------- mm/truncate.c | 6 +++++- 15 files changed, 60 insertions(+), 36 deletions(-) -- 2.9.3 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org