git.ipfire.org Git - thirdparty/kernel/stable-queue.git/blob

   1 From 337382e09a38ac79003ca41d5d7c36aaf252ad7b Mon Sep 17 00:00:00 2001
   2 From: Sasha Levin <sashal@kernel.org>
   3 Date: Wed, 28 Oct 2020 15:24:34 +0800
   4 Subject: nbd: don't update block size after device is started
   5
   6 From: Ming Lei <ming.lei@redhat.com>
   7
   8 [ Upstream commit b40813ddcd6bf9f01d020804e4cb8febc480b9e4 ]
   9
  10 Mounted NBD device can be resized, one use case is rbd-nbd.
  11
  12 Fix the issue by setting up default block size, then not touch it
  13 in nbd_size_update() any more. This kind of usage is aligned with loop
  14 which has same use case too.
  15
  16 Cc: stable@vger.kernel.org
  17 Fixes: c8a83a6b54d0 ("nbd: Use set_blocksize() to set device blocksize")
  18 Reported-by: lining <lining2020x@163.com>
  19 Signed-off-by: Ming Lei <ming.lei@redhat.com>
  20 Cc: Josef Bacik <josef@toxicpanda.com>
  21 Cc: Jan Kara <jack@suse.cz>
  22 Tested-by: lining <lining2020x@163.com>
  23 Signed-off-by: Jens Axboe <axboe@kernel.dk>
  24 Signed-off-by: Sasha Levin <sashal@kernel.org>
  25 ---
  26  drivers/block/nbd.c | 9 +++++----
  27  1 file changed, 5 insertions(+), 4 deletions(-)
  28
  29 diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
  30 index 52e1e71e81241..706115ecd9bee 100644
  31 --- a/drivers/block/nbd.c
  32 +++ b/drivers/block/nbd.c
  33 @@ -276,7 +276,7 @@ static void nbd_size_clear(struct nbd_device *nbd)
  34         }
  35  }
  36
  37 -static void nbd_size_update(struct nbd_device *nbd)
  38 +static void nbd_size_update(struct nbd_device *nbd, bool start)
  39  {
  40         struct nbd_config *config = nbd->config;
  41         struct block_device *bdev = bdget_disk(nbd->disk, 0);
  42 @@ -292,7 +292,8 @@ static void nbd_size_update(struct nbd_device *nbd)
  43         if (bdev) {
  44                 if (bdev->bd_disk) {
  45                         bd_set_size(bdev, config->bytesize);
  46 -                       set_blocksize(bdev, config->blksize);
  47 +                       if (start)
  48 +                               set_blocksize(bdev, config->blksize);
  49                 } else
  50                         bdev->bd_invalidated = 1;
  51                 bdput(bdev);
  52 @@ -307,7 +308,7 @@ static void nbd_size_set(struct nbd_device *nbd, loff_t blocksize,
  53         config->blksize = blocksize;
  54         config->bytesize = blocksize * nr_blocks;
  55         if (nbd->task_recv != NULL)
  56 -               nbd_size_update(nbd);
  57 +               nbd_size_update(nbd, false);
  58  }
  59
  60  static void nbd_complete_rq(struct request *req)
  61 @@ -1244,7 +1245,7 @@ static int nbd_start_device(struct nbd_device *nbd)
  62                 args->index = i;
  63                 queue_work(nbd->recv_workq, &args->work);
  64         }
  65 -       nbd_size_update(nbd);
  66 +       nbd_size_update(nbd, true);
  67         return error;
  68  }
  69
  70 --
  71 2.27.0
  72