stable inclusion
from stable-5.10.4
commit c5c1af1107d60955a265eae3437ee18b33138039
bugzilla: 46903

--------------------------------

[ Upstream commit fc332570 ]

reg_pages should always contain mr->npage since when the mr is finally
de-reg'd it is always subtracted out.

If there were any error exits then mlx5_ib_rereg_user_mr() would leave the
reg_pages adjusted and this will cause it to be double subtracted
eventually.

The manipulation of reg_pages is inherently connected to the umem, so lift
it out of set_mr_fields() and only adjust it around creating/destroying a
umem.

reg_pages is only used for diagnostics in sysfs.

Fixes: 7d0cc6ed ("IB/mlx5: Add MR cache for large UMR regions")
Link: https://lore.kernel.org/r/20201026131936.1335664-3-leon@kernel.orgSigned-off-by: NLeon Romanovsky <leonro@nvidia.com>
Signed-off-by: NJason Gunthorpe <jgg@nvidia.com>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Acked-by: NXie XiuQi <xiexiuqi@huawei.com>