| Message ID | 20241002150036.1339475-2-willy@infradead.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | nilfs2: Finish folio conversion | expand |
On Thu, Oct 3, 2024 at 12:00 AM Matthew Wilcox (Oracle) wrote: > > Since nilfs2 has a ->writepages operation already, ->writepage is only > called by the migration code. If we add a ->migrate_folio operation, > it won't even be used for that and so it can be deleted. > > Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> > --- > fs/nilfs2/inode.c | 33 +-------------------------------- > 1 file changed, 1 insertion(+), 32 deletions(-) > > diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c > index be6acf6e2bfc..f1b47b655672 100644 > --- a/fs/nilfs2/inode.c > +++ b/fs/nilfs2/inode.c > @@ -170,37 +170,6 @@ static int nilfs_writepages(struct address_space *mapping, > return err; > } > > -static int nilfs_writepage(struct page *page, struct writeback_control *wbc) > -{ > - struct folio *folio = page_folio(page); > - struct inode *inode = folio->mapping->host; > - int err; > - > - if (sb_rdonly(inode->i_sb)) { > - /* > - * It means that filesystem was remounted in read-only > - * mode because of error or metadata corruption. But we > - * have dirty pages that try to be flushed in background. > - * So, here we simply discard this dirty page. > - */ > - nilfs_clear_folio_dirty(folio); > - folio_unlock(folio); > - return -EROFS; > - } > - > - folio_redirty_for_writepage(wbc, folio); > - folio_unlock(folio); > - > - if (wbc->sync_mode == WB_SYNC_ALL) { > - err = nilfs_construct_segment(inode->i_sb); > - if (unlikely(err)) > - return err; > - } else if (wbc->for_reclaim) > - nilfs_flush_segment(inode->i_sb, inode->i_ino); > - > - return 0; > -} > - > static bool nilfs_dirty_folio(struct address_space *mapping, > struct folio *folio) > { > @@ -295,7 +264,6 @@ nilfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter) > } > > const struct address_space_operations nilfs_aops = { > - .writepage = nilfs_writepage, > .read_folio = nilfs_read_folio, > .writepages = nilfs_writepages, > .dirty_folio = nilfs_dirty_folio, > @@ -304,6 +272,7 @@ const struct address_space_operations nilfs_aops = { > .write_end = nilfs_write_end, > .invalidate_folio = block_invalidate_folio, > .direct_IO = nilfs_direct_IO, > + .migrate_folio = buffer_migrate_folio, > .is_partially_uptodate = block_is_partially_uptodate, > }; > After applying this patch, fsstress started causing kernel panics. Looking at the patch, I realized that migrate_folio needs to use buffer_migrate_folio_norefs, which checks for buffer head references. I was able to eliminate the kernel panic by setting migrate_folio as follows: + .migrate_folio = buffer_migrate_folio_norefs, I would like to continue load testing to avoid side effects of reclaim by completely eliminating nilfs_writepage (calling nilfs_flush_segment). So far, no problems have occurred even in tests with different block sizes or architectures, as long as I make the above changes. Thanks, Ryusuke Konishi
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c index be6acf6e2bfc..f1b47b655672 100644 --- a/fs/nilfs2/inode.c +++ b/fs/nilfs2/inode.c @@ -170,37 +170,6 @@ static int nilfs_writepages(struct address_space *mapping, return err; } -static int nilfs_writepage(struct page *page, struct writeback_control *wbc) -{ - struct folio *folio = page_folio(page); - struct inode *inode = folio->mapping->host; - int err; - - if (sb_rdonly(inode->i_sb)) { - /* - * It means that filesystem was remounted in read-only - * mode because of error or metadata corruption. But we - * have dirty pages that try to be flushed in background. - * So, here we simply discard this dirty page. - */ - nilfs_clear_folio_dirty(folio); - folio_unlock(folio); - return -EROFS; - } - - folio_redirty_for_writepage(wbc, folio); - folio_unlock(folio); - - if (wbc->sync_mode == WB_SYNC_ALL) { - err = nilfs_construct_segment(inode->i_sb); - if (unlikely(err)) - return err; - } else if (wbc->for_reclaim) - nilfs_flush_segment(inode->i_sb, inode->i_ino); - - return 0; -} - static bool nilfs_dirty_folio(struct address_space *mapping, struct folio *folio) { @@ -295,7 +264,6 @@ nilfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter) } const struct address_space_operations nilfs_aops = { - .writepage = nilfs_writepage, .read_folio = nilfs_read_folio, .writepages = nilfs_writepages, .dirty_folio = nilfs_dirty_folio, @@ -304,6 +272,7 @@ const struct address_space_operations nilfs_aops = { .write_end = nilfs_write_end, .invalidate_folio = block_invalidate_folio, .direct_IO = nilfs_direct_IO, + .migrate_folio = buffer_migrate_folio, .is_partially_uptodate = block_is_partially_uptodate, };
Since nilfs2 has a ->writepages operation already, ->writepage is only called by the migration code. If we add a ->migrate_folio operation, it won't even be used for that and so it can be deleted. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> --- fs/nilfs2/inode.c | 33 +-------------------------------- 1 file changed, 1 insertion(+), 32 deletions(-)