Commit 12d2966d authored Nov 30, 2019 by Naohiro Aota Committed by Linus Torvalds Dec 01, 2019

mm, swap: disallow swapon() on zoned block devices

A zoned block device consists of a number of zones.  Zones are either
conventional and accepting random writes or sequential and requiring
that writes be issued in LBA order from each zone write pointer
position.  For the write restriction, zoned block devices are not
suitable for a swap device.  Disallow swapon on them.

[akpm@linux-foundation.org: reflow and reword comment, per Christoph]
Link: http://lkml.kernel.org/r/20191015085814.637837-1-naohiro.aota@wdc.com


Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: "Theodore Y. Ts'o" <tytso@mit.edu>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent d2dfbe47

mm/swapfile.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -2887,6 +2887,13 @@ static int claim_swapfile(struct swap_info_struct p, struct inode inode)
		error = set_blocksize(p->bdev, PAGE_SIZE);
		if (error < 0)
		return error;
		/*
		* Zoned block devices contain zones that have a sequential
		* write only restriction. Hence zoned block devices are not
		* suitable for swapping. Disallow them here.
		*/
		if (blk_queue_is_zoned(p->bdev->bd_queue))
		return -EINVAL;
		p->flags \|= SWP_BLKDEV;
		} else if (S_ISREG(inode->i_mode)) {
		p->bdev = inode->i_sb->s_bdev;

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