Ilya Dryomov 85f5a4d666 rbd: don't return 0 on unmap if RBD_DEV_FLAG_REMOVING is set ...

There is a window between when RBD_DEV_FLAG_REMOVING is set and when
the device is removed from rbd_dev_list.  During this window, we set
"already" and return 0.

Returning 0 from write(2) can confuse userspace tools because
0 indicates that nothing was written.  In particular, "rbd unmap"
will retry the write multiple times a second:

  10:28:05.463299 write(4, "0", 1)        = 0
  10:28:05.463509 write(4, "0", 1)        = 0
  10:28:05.463720 write(4, "0", 1)        = 0
  10:28:05.463942 write(4, "0", 1)        = 0
  10:28:05.464155 write(4, "0", 1)        = 0

Cc: stable@vger.kernel.org
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Tested-by: Dongsheng Yang <dongsheng.yang@easystack.cn>

2019-01-10 09:45:09 +01:00

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aoe

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drbd

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mtip32xx

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paride

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rsxx

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xen-blkback

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zram

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amiflop.c

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ataflop.c

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brd.c

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cryptoloop.c

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floppy.c

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Kconfig

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loop.c

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loop.h

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Makefile

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nbd.c

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null_blk_main.c

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null_blk_zoned.c

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null_blk.h

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pktcdvd.c

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ps3disk.c

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ps3vram.c

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rbd_types.h

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rbd.c

rbd: don't return 0 on unmap if RBD_DEV_FLAG_REMOVING is set

2019-01-10 09:45:09 +01:00

skd_main.c

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skd_s1120.h

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sunvdc.c

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swim3.c

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swim_asm.S

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swim.c

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sx8.c

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umem.c

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umem.h

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virtio_blk.c

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xen-blkfront.c

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xsysace.c

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z2ram.c

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