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Date:   Fri, 31 Dec 2021 09:40:12 -0500
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Subject: Re: [RFC PATCH rdma-next 05/10] RDMA/rxe: Allow registering
 persistent flag for pmem MR only
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To:     "lizhijian@fujitsu.com" <lizhijian@fujitsu.com>,
        "linux-rdma@vger.kernel.org" <linux-rdma@vger.kernel.org>,
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        "leon@kernel.org" <leon@kernel.org>
Cc:     "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "mbloch@nvidia.com" <mbloch@nvidia.com>,
        "liweihang@huawei.com" <liweihang@huawei.com>,
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        "yangx.jy@fujitsu.com" <yangx.jy@fujitsu.com>,
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References: <20211228080717.10666-1-lizhijian@cn.fujitsu.com>
 <20211228080717.10666-6-lizhijian@cn.fujitsu.com>
 <45bfd837-a784-5ea2-7ae0-46e7e557b030@talpey.com>
 <15ad4285-7a74-2b3f-1c1e-823b36cfcf82@fujitsu.com>
From:   Tom Talpey <tom@talpey.com>
In-Reply-To: <15ad4285-7a74-2b3f-1c1e-823b36cfcf82@fujitsu.com>
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On 12/30/2021 10:34 PM, lizhijian@fujitsu.com wrote:

>>>    +static bool ib_check_flush_access_flags(struct ib_mr *mr, u32 flags)
>>> +{
>>> +    return mr->is_pmem || !(flags & IB_ACCESS_FLUSH_PERSISTENT);
>>> +}

>> Its name is confusing and needs to be clarified.
> 
> Err,  let me see.... a more suitable name is very welcome.

Since the subroutine is rather simple, and with only a single
reference in a single file, it would be best to just pull
the test inline and delete it. This would also remove some
inefficient code.

  	if (flags & IB_ACCESS_FLUSH_PERSISTENT) {
		if (!iova_in_pmem(mr, iova, length) {
			pr_err("Cannot set IB_ACCESS_FLUSH_PERSISTENT for non-pmem memory\n");
			mr->state = RXE_MR_STATE_INVALID;
			mr->umem = NULL;
			err = -EINVAL;
			goto err_release_umem;
		}
		mr-> ibmr.is_pmem = true;
	}
...