The patch titled
Subject: mm, swap: disallow swapon() on zoned block devices
has been added to the -mm tree. Its filename is
mm-swap-disallow-swapon-on-zoned-block-devices.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/mm-swap-disallow-swapon-on-zoned-block-devices.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/mm-swap-disallow-swapon-on-zoned-block-devices.patch
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------------------------------------------------------
From: Naohiro Aota <naohiro.aota@xxxxxxx>
Subject: 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.
Link: http://lkml.kernel.org/r/20191015085814.637837-1-naohiro.aota@xxxxxxx
Signed-off-by: Naohiro Aota <naohiro.aota@xxxxxxx>
Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: "Theodore Y. Ts'o" <tytso@xxxxxxx>
Cc: Hannes Reinecke <hare@xxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/swapfile.c | 8 ++++++++
1 file changed, 8 insertions(+)
--- a/mm/swapfile.c~mm-swap-disallow-swapon-on-zoned-block-devices
+++ a/mm/swapfile.c
@@ -2887,6 +2887,14 @@ static int claim_swapfile(struct swap_in
error = set_blocksize(p->bdev, PAGE_SIZE);
if (error < 0)
return error;
+ /*
+ * Zoned block device contains zones that have
+ * sequential write only restriction. For the restriction,
+ * zoned block devices are not suitable for a swap device.
+ * 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;
_
Patches currently in -mm which might be from naohiro.aota@xxxxxxx are
mm-swap-disallow-swapon-on-zoned-block-devices.patch
