Re: [RFC PATCH 3/7] drm/ttm: TTM fault handler helpers

From: "Thomas Hellström (VMware)" <thomas_os@shipmail.org>
To: Hillf Danton <hdanton@sina.com>,
	Thomas Hellstrom <thellstrom@vmware.com>
Cc: linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org,
	linux-mm@kvack.org, pv-drivers@vmware.com,
	linux-graphics-maintainer@vmware.com,
	Andrew Morton <akpm@linux-foundation.org>,
	Matthew Wilcox <willy@infradead.org>,
	Will Deacon <will.deacon@arm.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Rik van Riel <riel@surriel.com>, Minchan Kim <minchan@kernel.org>,
	Michal Hocko <mhocko@suse.com>, Huang Ying <ying.huang@intel.com>,
	Souptick Joarder <jrdr.linux@gmail.com>,
	jglisse@redhat.com, christian.koenig@amd.com,
	Christoph Hellwig <hch@infradead.org>
Subject: Re: [RFC PATCH 3/7] drm/ttm: TTM fault handler helpers
Date: Fri, 13 Sep 2019 16:34:02 +0200	[thread overview]
Message-ID: <f26f6096-8d11-82e4-390c-d110af8fdc49@shipmail.org> (raw)
In-Reply-To: <20190913134039.3164-1-hdanton@sina.com>

On 9/13/19 3:40 PM, Hillf Danton wrote:
> On Fri, 13 Sep 2019 11:32:09 +0200
>>   	err = ttm_mem_io_lock(man, true);
>> -	if (unlikely(err != 0)) {
>> -		ret = VM_FAULT_NOPAGE;
>> -		goto out_unlock;
>> -	}
>> +	if (unlikely(err != 0))
>> +		return VM_FAULT_NOPAGE;
>>   	err = ttm_mem_io_reserve_vm(bo);
>> -	if (unlikely(err != 0)) {
>> -		ret = VM_FAULT_SIGBUS;
>> -		goto out_io_unlock;
>> -	}
>> +	if (unlikely(err != 0))
>> +		return VM_FAULT_SIGBUS;
>>
> Hehe, no hurry.

Could you be a bit more specific?

Thanks,

Thomas

>
>> @@ -295,8 +307,28 @@ static vm_fault_t ttm_bo_vm_fault(struct vm_fault *vmf)
>>   	ret = VM_FAULT_NOPAGE;
>>   out_io_unlock:
>>   	ttm_mem_io_unlock(man);
>> -out_unlock:
>> +	return ret;
>> +}
>> +EXPORT_SYMBOL(ttm_bo_vm_fault_reserved);