DM-Devel Archive on lore.kernel.org
 help / color / Atom feed
From: Tejun Heo <tj@kernel.org>
To: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@kernel.dk>, Jan Kara <jack@suse.cz>,
	Mike Snitzer <snitzer@redhat.com>,
	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Jan Kara <jack@suse.com>, Josef Bacik <josef@toxicpanda.com>,
	Coly Li <colyli@suse.de>,
	linux-block@vger.kernel.org, Richard Weinberger <richard@nod.at>,
	dm-devel@redhat.com, linux-mtd@lists.infradead.org,
	Johannes Thumshirn <johannes.thumshirn@wdc.com>,
	linux-fsdevel@vger.kernel.org, xen-devel@lists.xenproject.org,
	linux-bcache@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [dm-devel] [PATCH 23/45] block: remove i_bdev
Date: Tue, 24 Nov 2020 14:37:05 -0500
Message-ID: <X71g4Tm+3RiRg4Gf@mtj.duckdns.org> (raw)
In-Reply-To: <20201124132751.3747337-24-hch@lst.de>

On Tue, Nov 24, 2020 at 02:27:29PM +0100, Christoph Hellwig wrote:
> Switch the block device lookup interfaces to directly work with a dev_t
> so that struct block_device references are only acquired by the
> blkdev_get variants (and the blk-cgroup special case).  This means that
> we not don't need an extra reference in the inode and can generally
     ^
     now
> simplify handling of struct block_device to keep the lookups contained
> in the core block layer code.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
...
> @@ -1689,14 +1599,12 @@ static int blkdev_open(struct inode * inode, struct file * filp)
>  	if ((filp->f_flags & O_ACCMODE) == 3)
>  		filp->f_mode |= FMODE_WRITE_IOCTL;
>  
> -	bdev = bd_acquire(inode);
> -	if (bdev == NULL)
> -		return -ENOMEM;
> -
> +	bdev = blkdev_get_by_dev(inode->i_rdev, filp->f_mode, filp);
> +	if (IS_ERR(bdev))
> +		return PTR_ERR(bdev);
>  	filp->f_mapping = bdev->bd_inode->i_mapping;
>  	filp->f_wb_err = filemap_sample_wb_err(filp->f_mapping);
> -
> -	return blkdev_get(bdev, filp->f_mode, filp);
> +	return 0;
>  }

I was wondering whether losing the stale bdev flushing in bd_acquire() would
cause user-visible behavior changes but can't see how it would given that
userland has no way of holding onto a specific instance of block inode.
Maybe it's something worth mentioning in the commit message?

Other than that, for the block part:

Acked-by: Tejun Heo <tj@kernel.org>

Thanks.

-- 
tejun

--
dm-devel mailing list
dm-devel@redhat.com
https://www.redhat.com/mailman/listinfo/dm-devel


  parent reply index

Thread overview: 90+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-24 13:27 [dm-devel] merge struct block_device and struct hd_struct v2 Christoph Hellwig
2020-11-24 13:27 ` [dm-devel] [PATCH 01/45] blk-cgroup: fix a hd_struct leak in blkcg_fill_root_iostats Christoph Hellwig
2020-11-25  6:41   ` Hannes Reinecke
2020-11-24 13:27 ` [dm-devel] [PATCH 02/45] filemap: consistently use ->f_mapping over ->i_mapping Christoph Hellwig
2020-11-24 13:53   ` Matthew Wilcox
2020-11-25  6:41   ` Hannes Reinecke
2020-11-25 12:16   ` Jan Kara
2020-11-24 13:27 ` [dm-devel] [PATCH 03/45] fs: remove get_super_thawed and get_super_exclusive_thawed Christoph Hellwig
2020-11-25  6:42   ` Hannes Reinecke
2020-11-25 12:19   ` Jan Kara
2020-11-24 13:27 ` [dm-devel] [PATCH 04/45] fs: simplify freeze_bdev/thaw_bdev Christoph Hellwig
2020-11-25  6:07   ` Chao Yu
2020-11-25 12:29   ` Jan Kara
2020-11-25 16:22     ` Christoph Hellwig
2020-11-24 13:27 ` [dm-devel] [PATCH 05/45] mtip32xx: remove the call to fsync_bdev on removal Christoph Hellwig
2020-11-25 12:31   ` Jan Kara
2020-11-24 13:27 ` [dm-devel] [PATCH 06/45] zram: remove the claim mechanism Christoph Hellwig
2020-11-25 12:37   ` Jan Kara
2020-11-24 13:27 ` [dm-devel] [PATCH 07/45] zram: do not call set_blocksize Christoph Hellwig
2020-11-24 13:27 ` [dm-devel] [PATCH 08/45] loop: " Christoph Hellwig
2020-11-25 13:37   ` Jan Kara
2020-11-24 13:27 ` [dm-devel] [PATCH 09/45] dm: simplify flush_bio initialization in __send_empty_flush Christoph Hellwig
2020-11-24 13:27 ` [dm-devel] [PATCH 10/45] dm: remove the block_device reference in struct mapped_device Christoph Hellwig
2020-11-24 13:27 ` [dm-devel] [PATCH 11/45] block: remove a duplicate __disk_get_part prototype Christoph Hellwig
2020-11-24 17:36   ` Tejun Heo
2020-11-24 13:27 ` [dm-devel] [PATCH 12/45] block: remove a superflous check in blkpg_do_ioctl Christoph Hellwig
2020-11-24 17:37   ` Tejun Heo
2020-11-25 13:39   ` Jan Kara
2020-11-24 13:27 ` [dm-devel] [PATCH 13/45] block: add a bdev_kobj helper Christoph Hellwig
2020-11-24 13:41   ` Coly Li
2020-11-24 17:37   ` Tejun Heo
2020-11-24 13:27 ` [dm-devel] [PATCH 14/45] block: use disk_part_iter_exit in disk_part_iter_next Christoph Hellwig
2020-11-24 17:37   ` Tejun Heo
2020-11-24 13:27 ` [dm-devel] [PATCH 15/45] block: use put_device in put_disk Christoph Hellwig
2020-11-24 17:37   ` Tejun Heo
2020-11-24 13:27 ` [dm-devel] [PATCH 16/45] block: change the hash used for looking up block devices Christoph Hellwig
2020-11-24 17:38   ` Tejun Heo
2020-11-24 13:27 ` [dm-devel] [PATCH 17/45] init: refactor name_to_dev_t Christoph Hellwig
2020-11-24 17:38   ` Tejun Heo
2020-11-24 13:27 ` [dm-devel] [PATCH 18/45] init: refactor devt_from_partuuid Christoph Hellwig
2020-11-24 17:38   ` Tejun Heo
2020-11-24 13:27 ` [dm-devel] [PATCH 19/45] init: cleanup match_dev_by_uuid and match_dev_by_label Christoph Hellwig
2020-11-24 17:39   ` Tejun Heo
2020-11-24 13:27 ` [dm-devel] [PATCH 20/45] block: refactor __blkdev_put Christoph Hellwig
2020-11-24 17:41   ` Tejun Heo
2020-11-24 13:27 ` [dm-devel] [PATCH 21/45] block: refactor blkdev_get Christoph Hellwig
2020-11-24 18:03   ` Tejun Heo
2020-11-24 13:27 ` [dm-devel] [PATCH 22/45] block: opencode devcgroup_inode_permission Christoph Hellwig
2020-11-24 18:05   ` Tejun Heo
2020-11-24 13:27 ` [dm-devel] [PATCH 23/45] block: remove i_bdev Christoph Hellwig
2020-11-24 13:38   ` Coly Li
2020-11-24 19:37   ` Tejun Heo [this message]
2020-11-25 16:29     ` Christoph Hellwig
2020-11-25 20:19       ` Tejun Heo
2020-11-24 13:27 ` [dm-devel] [PATCH 24/45] blk-cgroup: stop abusing get_gendisk Christoph Hellwig
2020-11-24 19:46   ` Tejun Heo
2020-11-24 13:27 ` [dm-devel] [PATCH 25/45] block: reference struct block_device from struct hd_struct Christoph Hellwig
2020-11-24 21:18   ` Tejun Heo
2020-11-25 16:45     ` Christoph Hellwig
2020-11-25 20:20       ` Tejun Heo
2020-11-26  8:16         ` Christoph Hellwig
2020-11-24 13:27 ` [dm-devel] [PATCH 26/45] block: remove ->bd_contains Christoph Hellwig
2020-11-24 21:19   ` Tejun Heo
2020-11-24 13:27 ` [dm-devel] [PATCH 27/45] block: simplify the block device claiming interface Christoph Hellwig
2020-11-24 21:19   ` Tejun Heo
2020-11-24 13:27 ` [dm-devel] [PATCH 28/45] block: simplify part_to_disk Christoph Hellwig
2020-11-24 21:20   ` Tejun Heo
2020-11-24 13:27 ` [dm-devel] [PATCH 29/45] block: initialize struct block_device in bdev_alloc Christoph Hellwig
2020-11-24 21:20   ` Tejun Heo
2020-11-24 13:27 ` [dm-devel] [PATCH 30/45] block: remove the nr_sects field in struct hd_struct Christoph Hellwig
2020-11-24 13:34   ` Coly Li
2020-11-25  6:10   ` Chao Yu
2020-11-24 13:27 ` [dm-devel] [PATCH 31/45] block: move disk stat accounting to struct block_device Christoph Hellwig
2020-11-24 13:27 ` [dm-devel] [PATCH 32/45] block: move the start_sect field " Christoph Hellwig
2020-11-24 13:27 ` [dm-devel] [PATCH 33/45] block: move the partition_meta_info " Christoph Hellwig
2020-11-24 13:27 ` [dm-devel] [PATCH 34/45] block: move holder_dir " Christoph Hellwig
2020-11-24 13:27 ` [dm-devel] [PATCH 35/45] block: move make_it_fail " Christoph Hellwig
2020-11-24 13:27 ` [dm-devel] [PATCH 36/45] block: move the policy field " Christoph Hellwig
2020-11-24 13:27 ` [dm-devel] [PATCH 37/45] block: allocate struct hd_struct as part of struct bdev_inode Christoph Hellwig
2020-11-24 13:27 ` [dm-devel] [PATCH 38/45] block: switch partition lookup to use struct block_device Christoph Hellwig
2020-11-24 13:32   ` Coly Li
2020-11-25  6:11   ` Chao Yu
2020-11-24 13:27 ` [dm-devel] [PATCH 39/45] block: remove the partno field from struct hd_struct Christoph Hellwig
2020-11-24 13:27 ` [dm-devel] [PATCH 40/45] block: pass a block_device to blk_alloc_devt Christoph Hellwig
2020-11-24 13:27 ` [dm-devel] [PATCH 41/45] block: pass a block_device to invalidate_partition Christoph Hellwig
2020-11-24 13:27 ` [dm-devel] [PATCH 42/45] block: switch disk_part_iter_* to use a struct block_device Christoph Hellwig
2020-11-24 13:27 ` [dm-devel] [PATCH 43/45] f2fs: remove a few bd_part checks Christoph Hellwig
2020-11-25  6:12   ` Chao Yu
2020-11-24 13:27 ` [dm-devel] [PATCH 44/45] block: merge struct block_device and struct hd_struct Christoph Hellwig
2020-11-24 13:27 ` [dm-devel] [PATCH 45/45] block: stop using bdget_disk for partition 0 Christoph Hellwig

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=X71g4Tm+3RiRg4Gf@mtj.duckdns.org \
    --to=tj@kernel.org \
    --cc=axboe@kernel.dk \
    --cc=colyli@suse.de \
    --cc=dm-devel@redhat.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=hch@lst.de \
    --cc=jack@suse.com \
    --cc=jack@suse.cz \
    --cc=johannes.thumshirn@wdc.com \
    --cc=josef@toxicpanda.com \
    --cc=konrad.wilk@oracle.com \
    --cc=linux-bcache@vger.kernel.org \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-mtd@lists.infradead.org \
    --cc=richard@nod.at \
    --cc=snitzer@redhat.com \
    --cc=xen-devel@lists.xenproject.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

DM-Devel Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/dm-devel/0 dm-devel/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 dm-devel dm-devel/ https://lore.kernel.org/dm-devel \
		dm-devel@redhat.com
	public-inbox-index dm-devel

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/com.redhat.dm-devel


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git