From patchwork Tue Sep 15 15:18:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11778185 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 06568618 for ; Tue, 15 Sep 2020 22:53:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DA47B21D94 for ; Tue, 15 Sep 2020 22:53:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="ZfH9OPi1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727468AbgIOWxm (ORCPT ); Tue, 15 Sep 2020 18:53:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44996 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727139AbgIOPjo (ORCPT ); Tue, 15 Sep 2020 11:39:44 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E5092C06121F; Tue, 15 Sep 2020 08:38:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=G+PcVVvNdLxqrqHZKywZ8EiCzFgI5DVHnXDz6Ehqix4=; b=ZfH9OPi1RcPedfZh9NAwOTjcM/ z2bywMJy6L18CDMk7T2NqQg8hLqBWaZRVvxL4Bvmun4XgOm5NjPYkh8TkeNpvVg2wYuyMR1wL/sBL Z8ZXTHhS1OP1o9agt0BPLK10BAbwwJperBE9YBfJJ55CDLjSAJxm2KCaFei5PFj+gDcBw2KrMbQ+m PyS/t1JiMI0vxRn/JAfmdADJN9q4PEE73SHChS3AWHHSU79EwC1H7XsS0j+VBdhRi1WkDhgWo5cp1 EJ2enZ9wpRKRHlsYYYcrvhA782HboTJDKv8VAZpisCuR2swph4jt926/QveYBbRaW3jifJ+CPrg4C p+SGG2gw==; Received: from 089144214092.atnat0023.highway.a1.net ([89.144.214.92] helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1kID24-0002Cm-Ax; Tue, 15 Sep 2020 15:38:12 +0000 From: Christoph Hellwig To: Jens Axboe Cc: Song Liu , Hans de Goede , Richard Weinberger , Minchan Kim , Johannes Thumshirn , linux-mtd@lists.infradead.org, dm-devel@redhat.com, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, drbd-dev@lists.linbit.com, linux-raid@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, cgroups@vger.kernel.org, Johannes Thumshirn Subject: [PATCH 08/12] bdi: remove BDI_CAP_SYNCHRONOUS_IO Date: Tue, 15 Sep 2020 17:18:25 +0200 Message-Id: <20200915151829.1767176-9-hch@lst.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200915151829.1767176-1-hch@lst.de> References: <20200915151829.1767176-1-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 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org BDI_CAP_SYNCHRONOUS_IO is only checked in the swap code, and used to decided if ->rw_page can be used on a block device. Just check up for the method instead. The only complication is that zram needs a second set of block_device_operations as it can switch between modes that actually support ->rw_page and those who don't. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn --- drivers/block/brd.c | 1 - drivers/block/zram/zram_drv.c | 19 +++++++++++++------ drivers/nvdimm/btt.c | 2 -- drivers/nvdimm/pmem.c | 1 - include/linux/backing-dev.h | 9 --------- mm/swapfile.c | 2 +- 6 files changed, 14 insertions(+), 20 deletions(-) diff --git a/drivers/block/brd.c b/drivers/block/brd.c index 2723a70eb85593..cc49a921339f77 100644 --- a/drivers/block/brd.c +++ b/drivers/block/brd.c @@ -403,7 +403,6 @@ static struct brd_device *brd_alloc(int i) disk->flags = GENHD_FL_EXT_DEVT; sprintf(disk->disk_name, "ram%d", i); set_capacity(disk, rd_size * 2); - brd->brd_queue->backing_dev_info->capabilities |= BDI_CAP_SYNCHRONOUS_IO; /* Tell the block layer that this is not a rotational device */ blk_queue_flag_set(QUEUE_FLAG_NONROT, brd->brd_queue); diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index a356275605b104..1b51bb664f91f5 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -52,6 +52,9 @@ static unsigned int num_devices = 1; */ static size_t huge_class_size; +static const struct block_device_operations zram_devops; +static const struct block_device_operations zram_wb_devops; + static void zram_free_page(struct zram *zram, size_t index); static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec, u32 index, int offset, struct bio *bio); @@ -408,8 +411,7 @@ static void reset_bdev(struct zram *zram) zram->backing_dev = NULL; zram->old_block_size = 0; zram->bdev = NULL; - zram->disk->queue->backing_dev_info->capabilities |= - BDI_CAP_SYNCHRONOUS_IO; + zram->disk->fops = &zram_devops; kvfree(zram->bitmap); zram->bitmap = NULL; } @@ -528,8 +530,7 @@ static ssize_t backing_dev_store(struct device *dev, * freely but in fact, IO is going on so finally could cause * use-after-free when the IO is really done. */ - zram->disk->queue->backing_dev_info->capabilities &= - ~BDI_CAP_SYNCHRONOUS_IO; + zram->disk->fops = &zram_wb_devops; up_write(&zram->init_lock); pr_info("setup backing device %s\n", file_name); @@ -1819,6 +1820,13 @@ static const struct block_device_operations zram_devops = { .owner = THIS_MODULE }; +static const struct block_device_operations zram_wb_devops = { + .open = zram_open, + .submit_bio = zram_submit_bio, + .swap_slot_free_notify = zram_slot_free_notify, + .owner = THIS_MODULE +}; + static DEVICE_ATTR_WO(compact); static DEVICE_ATTR_RW(disksize); static DEVICE_ATTR_RO(initstate); @@ -1946,8 +1954,7 @@ static int zram_add(void) if (ZRAM_LOGICAL_BLOCK_SIZE == PAGE_SIZE) blk_queue_max_write_zeroes_sectors(zram->disk->queue, UINT_MAX); - zram->disk->queue->backing_dev_info->capabilities |= - (BDI_CAP_STABLE_WRITES | BDI_CAP_SYNCHRONOUS_IO); + zram->disk->queue->backing_dev_info->capabilities |= BDI_CAP_STABLE_WRITES; device_add_disk(NULL, zram->disk, zram_disk_attr_groups); strlcpy(zram->compressor, default_compressor, sizeof(zram->compressor)); diff --git a/drivers/nvdimm/btt.c b/drivers/nvdimm/btt.c index 0d710140bf93be..12ff6f8784ac11 100644 --- a/drivers/nvdimm/btt.c +++ b/drivers/nvdimm/btt.c @@ -1537,8 +1537,6 @@ static int btt_blk_init(struct btt *btt) btt->btt_disk->private_data = btt; btt->btt_disk->queue = btt->btt_queue; btt->btt_disk->flags = GENHD_FL_EXT_DEVT; - btt->btt_disk->queue->backing_dev_info->capabilities |= - BDI_CAP_SYNCHRONOUS_IO; blk_queue_logical_block_size(btt->btt_queue, btt->sector_size); blk_queue_max_hw_sectors(btt->btt_queue, UINT_MAX); diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c index 140cf3b9000c60..1711fdfd8d2816 100644 --- a/drivers/nvdimm/pmem.c +++ b/drivers/nvdimm/pmem.c @@ -475,7 +475,6 @@ static int pmem_attach_disk(struct device *dev, disk->queue = q; disk->flags = GENHD_FL_EXT_DEVT; disk->private_data = pmem; - disk->queue->backing_dev_info->capabilities |= BDI_CAP_SYNCHRONOUS_IO; nvdimm_namespace_disk_name(ndns, disk->disk_name); set_capacity(disk, (pmem->size - pmem->pfn_pad - pmem->data_offset) / 512); diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 52583b6f2ea05d..860ea33571bce5 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -122,9 +122,6 @@ int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ratio); * BDI_CAP_NO_WRITEBACK: Don't write pages back * BDI_CAP_NO_ACCT_WB: Don't automatically account writeback pages * BDI_CAP_STRICTLIMIT: Keep number of dirty pages below bdi threshold. - * - * BDI_CAP_SYNCHRONOUS_IO: Device is so fast that asynchronous IO would be - * inefficient. */ #define BDI_CAP_NO_ACCT_DIRTY 0x00000001 #define BDI_CAP_NO_WRITEBACK 0x00000002 @@ -132,7 +129,6 @@ int bdi_set_max_ratio(struct backing_dev_info *bdi, unsigned int max_ratio); #define BDI_CAP_STABLE_WRITES 0x00000008 #define BDI_CAP_STRICTLIMIT 0x00000010 #define BDI_CAP_CGROUP_WRITEBACK 0x00000020 -#define BDI_CAP_SYNCHRONOUS_IO 0x00000040 #define BDI_CAP_NO_ACCT_AND_WRITEBACK \ (BDI_CAP_NO_WRITEBACK | BDI_CAP_NO_ACCT_DIRTY | BDI_CAP_NO_ACCT_WB) @@ -174,11 +170,6 @@ static inline int wb_congested(struct bdi_writeback *wb, int cong_bits) long congestion_wait(int sync, long timeout); long wait_iff_congested(int sync, long timeout); -static inline bool bdi_cap_synchronous_io(struct backing_dev_info *bdi) -{ - return bdi->capabilities & BDI_CAP_SYNCHRONOUS_IO; -} - static inline bool bdi_cap_stable_pages_required(struct backing_dev_info *bdi) { return bdi->capabilities & BDI_CAP_STABLE_WRITES; diff --git a/mm/swapfile.c b/mm/swapfile.c index 12f59e641b5e29..986fe5aad30e18 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -3237,7 +3237,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) if (bdi_cap_stable_pages_required(inode_to_bdi(inode))) p->flags |= SWP_STABLE_WRITES; - if (bdi_cap_synchronous_io(inode_to_bdi(inode))) + if (p->bdev && p->bdev->bd_disk->fops->rw_page) p->flags |= SWP_SYNCHRONOUS_IO; if (p->bdev && blk_queue_nonrot(bdev_get_queue(p->bdev))) {