From patchwork Tue Jan 26 14:52:35 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 12046969 X-Patchwork-Delegate: snitzer@redhat.com Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 23C84C433E0 for ; Tue, 26 Jan 2021 15:04:04 +0000 (UTC) Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [63.128.21.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9705B23101 for ; Tue, 26 Jan 2021 15:04:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9705B23101 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=tempfail smtp.mailfrom=dm-devel-bounces@redhat.com Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-548-DCxOon2GPWyyJ_NFC-4NuQ-1; Tue, 26 Jan 2021 10:04:00 -0500 X-MC-Unique: DCxOon2GPWyyJ_NFC-4NuQ-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id CFE5C801AB5; Tue, 26 Jan 2021 15:03:55 +0000 (UTC) Received: from colo-mx.corp.redhat.com (colo-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id A7A1E10013C0; Tue, 26 Jan 2021 15:03:55 +0000 (UTC) Received: from lists01.pubmisc.prod.ext.phx2.redhat.com (lists01.pubmisc.prod.ext.phx2.redhat.com [10.5.19.33]) by colo-mx.corp.redhat.com (Postfix) with ESMTP id 554C05002E; Tue, 26 Jan 2021 15:03:55 +0000 (UTC) Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) by lists01.pubmisc.prod.ext.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id 10QF3r3J012682 for ; Tue, 26 Jan 2021 10:03:53 -0500 Received: by smtp.corp.redhat.com (Postfix) id AE409110F75E; Tue, 26 Jan 2021 15:03:53 +0000 (UTC) Received: from mimecast-mx02.redhat.com (mimecast05.extmail.prod.ext.rdu2.redhat.com [10.11.55.21]) by smtp.corp.redhat.com (Postfix) with ESMTPS id AA18F110F72C for ; Tue, 26 Jan 2021 15:03:51 +0000 (UTC) Received: from us-smtp-1.mimecast.com (us-smtp-2.mimecast.com [207.211.31.81]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 5C485805F4E for ; Tue, 26 Jan 2021 15:03:51 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-425-xOUlmIIpOymdIWvDpcF0uQ-1; Tue, 26 Jan 2021 10:03:48 -0500 X-MC-Unique: xOUlmIIpOymdIWvDpcF0uQ-1 Received: from [2001:4bb8:191:e347:5918:ac86:61cb:8801] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.94 #2 (Red Hat Linux)) id 1l4PqP-005mns-Ef; Tue, 26 Jan 2021 15:01:48 +0000 From: Christoph Hellwig To: Jens Axboe , Song Liu Date: Tue, 26 Jan 2021 15:52:35 +0100 Message-Id: <20210126145247.1964410-6-hch@lst.de> In-Reply-To: <20210126145247.1964410-1-hch@lst.de> References: <20210126145247.1964410-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html X-Mimecast-Impersonation-Protect: Policy=CLT - Impersonation Protection Definition; Similar Internal Domain=false; Similar Monitored External Domain=false; Custom External Domain=false; Mimecast External Domain=false; Newly Observed Domain=false; Internal User Name=false; Custom Display Name List=false; Reply-to Address Mismatch=false; Targeted Threat Dictionary=false; Mimecast Threat Dictionary=false; Custom Threat Dictionary=false X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3 X-loop: dm-devel@redhat.com Cc: Mike Snitzer , David Sterba , dm-devel@redhat.com, Naohiro Aota , linux-nilfs@vger.kernel.org, Josef Bacik , Chao Yu , linux-nfs@vger.kernel.org, Coly Li , linux-raid@vger.kernel.org, linux-bcache@vger.kernel.org, drbd-dev@tron.linbit.com, Jaegeuk Kim , Ryusuke Konishi , linux-block@vger.kernel.org, Damien Le Moal , Andrew Morton , linux-mm@kvack.org, Philipp Reisner , linux-f2fs-devel@lists.sourceforge.net, linux-fsdevel@vger.kernel.org, Lars Ellenberg , linux-btrfs@vger.kernel.org Subject: [dm-devel] [PATCH 05/17] block: use an on-stack bio in blkdev_issue_flush X-BeenThere: dm-devel@redhat.com X-Mailman-Version: 2.1.12 Precedence: junk List-Id: device-mapper development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dm-devel-bounces@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com There is no point in allocating memory for a synchronous flush. Signed-off-by: Christoph Hellwig Reviewed-by: Chaitanya Kulkarni --- block/blk-flush.c | 17 ++++++----------- drivers/md/dm-zoned-metadata.c | 6 +++--- drivers/md/raid5-ppl.c | 2 +- drivers/nvme/target/io-cmd-bdev.c | 2 +- fs/block_dev.c | 2 +- fs/exfat/file.c | 2 +- fs/ext4/fast_commit.c | 4 ++-- fs/ext4/fsync.c | 2 +- fs/ext4/ialloc.c | 2 +- fs/ext4/super.c | 2 +- fs/fat/file.c | 2 +- fs/hfsplus/inode.c | 2 +- fs/hfsplus/super.c | 2 +- fs/jbd2/checkpoint.c | 2 +- fs/jbd2/commit.c | 4 ++-- fs/jbd2/recovery.c | 2 +- fs/libfs.c | 2 +- fs/nilfs2/the_nilfs.h | 2 +- fs/ocfs2/file.c | 2 +- fs/reiserfs/file.c | 2 +- fs/xfs/xfs_super.c | 2 +- fs/zonefs/super.c | 2 +- include/linux/blkdev.h | 4 ++-- 23 files changed, 33 insertions(+), 38 deletions(-) diff --git a/block/blk-flush.c b/block/blk-flush.c index 76c1624cb06c05..7942ca6ed3211c 100644 --- a/block/blk-flush.c +++ b/block/blk-flush.c @@ -432,23 +432,18 @@ void blk_insert_flush(struct request *rq) /** * blkdev_issue_flush - queue a flush * @bdev: blockdev to issue flush for - * @gfp_mask: memory allocation flags (for bio_alloc) * * Description: * Issue a flush for the block device in question. */ -int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask) +int blkdev_issue_flush(struct block_device *bdev) { - struct bio *bio; - int ret = 0; + struct bio bio; - bio = bio_alloc(gfp_mask, 0); - bio_set_dev(bio, bdev); - bio->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH; - - ret = submit_bio_wait(bio); - bio_put(bio); - return ret; + bio_init(&bio, NULL, 0); + bio_set_dev(&bio, bdev); + bio.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH; + return submit_bio_wait(&bio); } EXPORT_SYMBOL(blkdev_issue_flush); diff --git a/drivers/md/dm-zoned-metadata.c b/drivers/md/dm-zoned-metadata.c index b298fefb022eb9..039d17b2893849 100644 --- a/drivers/md/dm-zoned-metadata.c +++ b/drivers/md/dm-zoned-metadata.c @@ -819,7 +819,7 @@ static int dmz_write_sb(struct dmz_metadata *zmd, unsigned int set) ret = dmz_rdwr_block(dev, REQ_OP_WRITE, zmd->sb[set].block, mblk->page); if (ret == 0) - ret = blkdev_issue_flush(dev->bdev, GFP_NOIO); + ret = blkdev_issue_flush(dev->bdev); return ret; } @@ -862,7 +862,7 @@ static int dmz_write_dirty_mblocks(struct dmz_metadata *zmd, /* Flush drive cache (this will also sync data) */ if (ret == 0) - ret = blkdev_issue_flush(dev->bdev, GFP_NOIO); + ret = blkdev_issue_flush(dev->bdev); return ret; } @@ -933,7 +933,7 @@ int dmz_flush_metadata(struct dmz_metadata *zmd) /* If there are no dirty metadata blocks, just flush the device cache */ if (list_empty(&write_list)) { - ret = blkdev_issue_flush(dev->bdev, GFP_NOIO); + ret = blkdev_issue_flush(dev->bdev); goto err; } diff --git a/drivers/md/raid5-ppl.c b/drivers/md/raid5-ppl.c index d0f540296fe91e..e8c118e05dfd46 100644 --- a/drivers/md/raid5-ppl.c +++ b/drivers/md/raid5-ppl.c @@ -1037,7 +1037,7 @@ static int ppl_recover(struct ppl_log *log, struct ppl_header *pplhdr, } /* flush the disk cache after recovery if necessary */ - ret = blkdev_issue_flush(rdev->bdev, GFP_KERNEL); + ret = blkdev_issue_flush(rdev->bdev); out: __free_page(page); return ret; diff --git a/drivers/nvme/target/io-cmd-bdev.c b/drivers/nvme/target/io-cmd-bdev.c index 125dde3f410ee7..bf6e0ac9ad2890 100644 --- a/drivers/nvme/target/io-cmd-bdev.c +++ b/drivers/nvme/target/io-cmd-bdev.c @@ -333,7 +333,7 @@ static void nvmet_bdev_execute_flush(struct nvmet_req *req) u16 nvmet_bdev_flush(struct nvmet_req *req) { - if (blkdev_issue_flush(req->ns->bdev, GFP_KERNEL)) + if (blkdev_issue_flush(req->ns->bdev)) return NVME_SC_INTERNAL | NVME_SC_DNR; return 0; } diff --git a/fs/block_dev.c b/fs/block_dev.c index 6f5bd9950baf45..bc957ef7cebaae 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -681,7 +681,7 @@ int blkdev_fsync(struct file *filp, loff_t start, loff_t end, int datasync) * i_mutex and doing so causes performance issues with concurrent * O_SYNC writers to a block device. */ - error = blkdev_issue_flush(bdev, GFP_KERNEL); + error = blkdev_issue_flush(bdev); if (error == -EOPNOTSUPP) error = 0; diff --git a/fs/exfat/file.c b/fs/exfat/file.c index a92478eabfa4e4..183ffdf4d43c5f 100644 --- a/fs/exfat/file.c +++ b/fs/exfat/file.c @@ -361,7 +361,7 @@ int exfat_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync) if (err) return err; - return blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL); + return blkdev_issue_flush(inode->i_sb->s_bdev); } const struct file_operations exfat_file_operations = { diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c index 0a14a7c87bf82e..6e8208acfc62ac 100644 --- a/fs/ext4/fast_commit.c +++ b/fs/ext4/fast_commit.c @@ -1076,7 +1076,7 @@ static int ext4_fc_perform_commit(journal_t *journal) * flush before we start writing fast commit blocks. */ if (journal->j_fs_dev != journal->j_dev) - blkdev_issue_flush(journal->j_fs_dev, GFP_NOFS); + blkdev_issue_flush(journal->j_fs_dev); blk_start_plug(&plug); if (sbi->s_fc_bytes == 0) { @@ -1535,7 +1535,7 @@ static int ext4_fc_replay_inode(struct super_block *sb, struct ext4_fc_tl *tl) out: iput(inode); if (!ret) - blkdev_issue_flush(sb->s_bdev, GFP_KERNEL); + blkdev_issue_flush(sb->s_bdev); return 0; } diff --git a/fs/ext4/fsync.c b/fs/ext4/fsync.c index 113bfb023a4a09..027a7d7037a07b 100644 --- a/fs/ext4/fsync.c +++ b/fs/ext4/fsync.c @@ -174,7 +174,7 @@ int ext4_sync_file(struct file *file, loff_t start, loff_t end, int datasync) ret = ext4_fsync_journal(inode, datasync, &needs_barrier); if (needs_barrier) { - err = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL); + err = blkdev_issue_flush(inode->i_sb->s_bdev); if (!ret) ret = err; } diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c index b215c564bc318a..20f2fcb799f55f 100644 --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -1583,7 +1583,7 @@ int ext4_init_inode_table(struct super_block *sb, ext4_group_t group, if (ret < 0) goto err_out; if (barrier) - blkdev_issue_flush(sb->s_bdev, GFP_NOFS); + blkdev_issue_flush(sb->s_bdev); skip_zeroout: ext4_lock_group(sb, group); diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 9a6f9875aa3499..fb5985102c1db7 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -5709,7 +5709,7 @@ static int ext4_sync_fs(struct super_block *sb, int wait) needs_barrier = true; if (needs_barrier) { int err; - err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL); + err = blkdev_issue_flush(sb->s_bdev); if (!ret) ret = err; } diff --git a/fs/fat/file.c b/fs/fat/file.c index f9ee27cf4d7c2f..5fee74f1ad611d 100644 --- a/fs/fat/file.c +++ b/fs/fat/file.c @@ -195,7 +195,7 @@ int fat_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync) if (err) return err; - return blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL); + return blkdev_issue_flush(inode->i_sb->s_bdev); } diff --git a/fs/hfsplus/inode.c b/fs/hfsplus/inode.c index e3da9e96b83578..ca464328b79cc5 100644 --- a/fs/hfsplus/inode.c +++ b/fs/hfsplus/inode.c @@ -340,7 +340,7 @@ int hfsplus_file_fsync(struct file *file, loff_t start, loff_t end, } if (!test_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags)) - blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL); + blkdev_issue_flush(inode->i_sb->s_bdev); inode_unlock(inode); diff --git a/fs/hfsplus/super.c b/fs/hfsplus/super.c index 807119ae5adf73..b9e3db3f855f96 100644 --- a/fs/hfsplus/super.c +++ b/fs/hfsplus/super.c @@ -239,7 +239,7 @@ static int hfsplus_sync_fs(struct super_block *sb, int wait) mutex_unlock(&sbi->vh_mutex); if (!test_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags)) - blkdev_issue_flush(sb->s_bdev, GFP_KERNEL); + blkdev_issue_flush(sb->s_bdev); return error; } diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c index 472932b9e6bca9..63b526d44886d0 100644 --- a/fs/jbd2/checkpoint.c +++ b/fs/jbd2/checkpoint.c @@ -416,7 +416,7 @@ int jbd2_cleanup_journal_tail(journal_t *journal) * jbd2_cleanup_journal_tail() doesn't get called all that often. */ if (journal->j_flags & JBD2_BARRIER) - blkdev_issue_flush(journal->j_fs_dev, GFP_NOFS); + blkdev_issue_flush(journal->j_fs_dev); return __jbd2_update_log_tail(journal, first_tid, blocknr); } diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index b121d7d434c675..3cc4ab2ba7f4f2 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -825,7 +825,7 @@ void jbd2_journal_commit_transaction(journal_t *journal) if (commit_transaction->t_need_data_flush && (journal->j_fs_dev != journal->j_dev) && (journal->j_flags & JBD2_BARRIER)) - blkdev_issue_flush(journal->j_fs_dev, GFP_NOFS); + blkdev_issue_flush(journal->j_fs_dev); /* Done it all: now write the commit record asynchronously. */ if (jbd2_has_feature_async_commit(journal)) { @@ -932,7 +932,7 @@ void jbd2_journal_commit_transaction(journal_t *journal) stats.run.rs_blocks_logged++; if (jbd2_has_feature_async_commit(journal) && journal->j_flags & JBD2_BARRIER) { - blkdev_issue_flush(journal->j_dev, GFP_NOFS); + blkdev_issue_flush(journal->j_dev); } if (err) diff --git a/fs/jbd2/recovery.c b/fs/jbd2/recovery.c index dc0694fcfcd123..69f18fe2092369 100644 --- a/fs/jbd2/recovery.c +++ b/fs/jbd2/recovery.c @@ -326,7 +326,7 @@ int jbd2_journal_recover(journal_t *journal) err = err2; /* Make sure all replayed data is on permanent storage */ if (journal->j_flags & JBD2_BARRIER) { - err2 = blkdev_issue_flush(journal->j_fs_dev, GFP_KERNEL); + err2 = blkdev_issue_flush(journal->j_fs_dev); if (!err) err = err2; } diff --git a/fs/libfs.c b/fs/libfs.c index d1c3bade9f30dd..8398a0efb401c6 100644 --- a/fs/libfs.c +++ b/fs/libfs.c @@ -1117,7 +1117,7 @@ int generic_file_fsync(struct file *file, loff_t start, loff_t end, err = __generic_file_fsync(file, start, end, datasync); if (err) return err; - return blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL); + return blkdev_issue_flush(inode->i_sb->s_bdev); } EXPORT_SYMBOL(generic_file_fsync); diff --git a/fs/nilfs2/the_nilfs.h b/fs/nilfs2/the_nilfs.h index b55cdeb4d16991..987c8ab02aeee6 100644 --- a/fs/nilfs2/the_nilfs.h +++ b/fs/nilfs2/the_nilfs.h @@ -375,7 +375,7 @@ static inline int nilfs_flush_device(struct the_nilfs *nilfs) */ smp_wmb(); - err = blkdev_issue_flush(nilfs->ns_bdev, GFP_KERNEL); + err = blkdev_issue_flush(nilfs->ns_bdev); if (err != -EIO) err = 0; return err; diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c index 85979e2214b39d..df6d709d2ae3b6 100644 --- a/fs/ocfs2/file.c +++ b/fs/ocfs2/file.c @@ -194,7 +194,7 @@ static int ocfs2_sync_file(struct file *file, loff_t start, loff_t end, needs_barrier = true; err = jbd2_complete_transaction(journal, commit_tid); if (needs_barrier) { - ret = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL); + ret = blkdev_issue_flush(inode->i_sb->s_bdev); if (!err) err = ret; } diff --git a/fs/reiserfs/file.c b/fs/reiserfs/file.c index 0b641ae694f123..1db0254bc38b26 100644 --- a/fs/reiserfs/file.c +++ b/fs/reiserfs/file.c @@ -159,7 +159,7 @@ static int reiserfs_sync_file(struct file *filp, loff_t start, loff_t end, barrier_done = reiserfs_commit_for_inode(inode); reiserfs_write_unlock(inode->i_sb); if (barrier_done != 1 && reiserfs_barrier_flush(inode->i_sb)) - blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL); + blkdev_issue_flush(inode->i_sb->s_bdev); inode_unlock(inode); if (barrier_done < 0) return barrier_done; diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index 813be879a5e51d..c3e32789829f90 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -342,7 +342,7 @@ void xfs_blkdev_issue_flush( xfs_buftarg_t *buftarg) { - blkdev_issue_flush(buftarg->bt_bdev, GFP_NOFS); + blkdev_issue_flush(buftarg->bt_bdev); } STATIC void diff --git a/fs/zonefs/super.c b/fs/zonefs/super.c index faea2ed34b4a37..ab68e27bb322e0 100644 --- a/fs/zonefs/super.c +++ b/fs/zonefs/super.c @@ -541,7 +541,7 @@ static int zonefs_file_fsync(struct file *file, loff_t start, loff_t end, if (ZONEFS_I(inode)->i_ztype == ZONEFS_ZTYPE_CNV) ret = file_write_and_wait_range(file, start, end); if (!ret) - ret = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL); + ret = blkdev_issue_flush(inode->i_sb->s_bdev); if (ret) zonefs_io_error(inode, true); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 20f3706b6b2e68..09f7ac5507d146 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1288,7 +1288,7 @@ static inline bool blk_needs_flush_plug(struct task_struct *tsk) !list_empty(&plug->cb_list)); } -int blkdev_issue_flush(struct block_device *, gfp_t); +int blkdev_issue_flush(struct block_device *bdev); long nr_blockdev_pages(void); #else /* CONFIG_BLOCK */ struct blk_plug { @@ -1316,7 +1316,7 @@ static inline bool blk_needs_flush_plug(struct task_struct *tsk) return false; } -static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask) +static inline int blkdev_issue_flush(struct block_device *bdev) { return 0; }