From patchwork Mon Sep 21 14:43:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Goldwyn Rodrigues X-Patchwork-Id: 11790237 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3E21859D for ; Mon, 21 Sep 2020 14:44:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2D3BD221EC for ; Mon, 21 Sep 2020 14:44:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727945AbgIUOoy (ORCPT ); Mon, 21 Sep 2020 10:44:54 -0400 Received: from mx2.suse.de ([195.135.220.15]:56440 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728323AbgIUOor (ORCPT ); Mon, 21 Sep 2020 10:44:47 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 1B37FB0D7; Mon, 21 Sep 2020 14:45:21 +0000 (UTC) From: Goldwyn Rodrigues To: linux-fsdevel@vger.kernel.org Cc: linux-btrfs@vger.kernel.org, david@fromorbit.com, hch@lst.de, johannes.thumshirn@wdc.com, dsterba@suse.com, darrick.wong@oracle.com, josef@toxicpanda.com, Goldwyn Rodrigues Subject: [PATCH 14/15] btrfs: Revert 09745ff88d93 ("btrfs: dio iomap DSYNC workaround") Date: Mon, 21 Sep 2020 09:43:52 -0500 Message-Id: <20200921144353.31319-15-rgoldwyn@suse.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200921144353.31319-1-rgoldwyn@suse.de> References: <20200921144353.31319-1-rgoldwyn@suse.de> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org From: Goldwyn Rodrigues iomap_dio_complete()->generic_write_sync() is not called under i_rwsem anymore, revert the workaround. Signed-off-by: Goldwyn Rodrigues Reviewed-by: Josef Bacik --- fs/btrfs/ctree.h | 1 - fs/btrfs/file.c | 38 ++------------------------------ fs/btrfs/inode.c | 50 ------------------------------------------ fs/btrfs/transaction.h | 1 - 4 files changed, 2 insertions(+), 88 deletions(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index ea15771bf3da..bc96c52021b2 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -3051,7 +3051,6 @@ void btrfs_writepage_endio_finish_ordered(struct page *page, u64 start, extern const struct dentry_operations btrfs_dentry_operations; extern const struct iomap_ops btrfs_dio_iomap_ops; extern const struct iomap_dio_ops btrfs_dio_ops; -extern const struct iomap_dio_ops btrfs_sync_dops; /* ilock flags definition */ #define BTRFS_ILOCK_SHARED (1 << 0) diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 9c7a2d4b4148..1d3363e7b09d 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -2094,44 +2094,10 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb, if (sync) atomic_inc(&BTRFS_I(inode)->sync_writers); - if (iocb->ki_flags & IOCB_DIRECT) { - /* - * 1. We must always clear IOCB_DSYNC in order to not deadlock - * in iomap, as it calls generic_write_sync() in this case. - * 2. If we are async, we can call iomap_dio_complete() either - * in - * - * 2.1. A worker thread from the last bio completed. In this - * case we need to mark the btrfs_dio_data that it is - * async in order to call generic_write_sync() properly. - * This is handled by setting BTRFS_DIO_SYNC_STUB in the - * current->journal_info. - * 2.2 The submitter context, because all IO completed - * before we exited iomap_dio_rw(). In this case we can - * just re-set the IOCB_DSYNC on the iocb and we'll do - * the sync below. If our ->end_io() gets called and - * current->journal_info is set, then we know we're in - * our current context and we will clear - * current->journal_info to indicate that we need to - * sync below. - */ - if (sync) { - ASSERT(current->journal_info == NULL); - iocb->ki_flags &= ~IOCB_DSYNC; - current->journal_info = BTRFS_DIO_SYNC_STUB; - } + if (iocb->ki_flags & IOCB_DIRECT) num_written = btrfs_direct_write(iocb, from); - - /* - * As stated above, we cleared journal_info, so we need to do - * the sync ourselves. - */ - if (sync && current->journal_info == NULL) - iocb->ki_flags |= IOCB_DSYNC; - current->journal_info = NULL; - } else { + else num_written = btrfs_buffered_write(iocb, from); - } /* * We also have to set last_sub_trans to the current log transid, diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 96ff8e4a3b45..41e32ef6b6ef 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -62,7 +62,6 @@ struct btrfs_dio_data { loff_t length; ssize_t submitted; struct extent_changeset *data_reserved; - bool sync; }; static const struct inode_operations btrfs_dir_inode_operations; @@ -7362,17 +7361,6 @@ static int btrfs_dio_iomap_begin(struct inode *inode, loff_t start, int ret = 0; u64 len = length; bool unlock_extents = false; - bool sync = (current->journal_info == BTRFS_DIO_SYNC_STUB); - - /* - * We used current->journal_info here to see if we were sync, but - * there's a lot of tests in the enospc machinery to not do flushing if - * we have a journal_info set, so we need to clear this out and re-set - * it in iomap_end. - */ - ASSERT(current->journal_info == NULL || - current->journal_info == BTRFS_DIO_SYNC_STUB); - current->journal_info = NULL; if (!write) len = min_t(u64, len, fs_info->sectorsize); @@ -7398,7 +7386,6 @@ static int btrfs_dio_iomap_begin(struct inode *inode, loff_t start, if (!dio_data) return -ENOMEM; - dio_data->sync = sync; dio_data->length = length; if (write) { dio_data->reserve = round_up(length, fs_info->sectorsize); @@ -7546,14 +7533,6 @@ static int btrfs_dio_iomap_end(struct inode *inode, loff_t pos, loff_t length, extent_changeset_free(dio_data->data_reserved); } out: - /* - * We're all done, we can re-set the current->journal_info now safely - * for our endio. - */ - if (dio_data->sync) { - ASSERT(current->journal_info == NULL); - current->journal_info = BTRFS_DIO_SYNC_STUB; - } kfree(dio_data); iomap->private = NULL; @@ -7929,30 +7908,6 @@ static blk_qc_t btrfs_submit_direct(struct inode *inode, struct iomap *iomap, return BLK_QC_T_NONE; } -static inline int btrfs_maybe_fsync_end_io(struct kiocb *iocb, ssize_t size, - int error, unsigned flags) -{ - /* - * Now if we're still in the context of our submitter we know we can't - * safely run generic_write_sync(), so clear our flag here so that the - * caller knows to follow up with a sync. - */ - if (current->journal_info == BTRFS_DIO_SYNC_STUB) { - current->journal_info = NULL; - return error; - } - - if (error) - return error; - - if (size) { - iocb->ki_flags |= IOCB_DSYNC; - return generic_write_sync(iocb, size); - } - - return 0; -} - const struct iomap_ops btrfs_dio_iomap_ops = { .iomap_begin = btrfs_dio_iomap_begin, .iomap_end = btrfs_dio_iomap_end, @@ -7962,11 +7917,6 @@ const struct iomap_dio_ops btrfs_dio_ops = { .submit_io = btrfs_submit_direct, }; -const struct iomap_dio_ops btrfs_sync_dops = { - .submit_io = btrfs_submit_direct, - .end_io = btrfs_maybe_fsync_end_io, -}; - static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, u64 start, u64 len) { diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h index 858d9153a1cd..8241c050ba71 100644 --- a/fs/btrfs/transaction.h +++ b/fs/btrfs/transaction.h @@ -112,7 +112,6 @@ struct btrfs_transaction { #define TRANS_EXTWRITERS (__TRANS_START | __TRANS_ATTACH) #define BTRFS_SEND_TRANS_STUB ((void *)1) -#define BTRFS_DIO_SYNC_STUB ((void *)2) struct btrfs_trans_handle { u64 transid;