dm zoned: target: use refcount_t for dm zoned reference counters
authorJohn Pittman <jpittman@redhat.com>
Thu, 23 Aug 2018 17:35:57 +0000 (13:35 -0400)
committerMike Snitzer <snitzer@redhat.com>
Tue, 16 Oct 2018 18:27:38 +0000 (14:27 -0400)
commit092b5648760a23656f6dcc83b74f4cf661094aca
tree6f3d1b43bf3cd0caa7a8ac3fa4b60f37221f519e
parent22d4c291f58752d14efb8a185b772a3fc3e947d2
dm zoned: target: use refcount_t for dm zoned reference counters

The API surrounding refcount_t should be used in place of atomic_t
when variables are being used as reference counters.  This API can
prevent issues such as counter overflows and use-after-free
conditions.  Within the dm zoned target stack, the atomic_t API is
used for bioctx->ref and cw->refcount.  Change these to use
refcount_t, avoiding the issues mentioned.

Signed-off-by: John Pittman <jpittman@redhat.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Tested-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
drivers/md/dm-zoned-target.c