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

From: Hillf Danton <hdanton@sina.com>
To: Thomas Hellstrom <thomas_os@shipmail.org>,
	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 21:40:39 +0800	[thread overview]
Message-ID: <20190913134039.3164-1-hdanton@sina.com> (raw)
In-Reply-To: <20190913093213.27254-1-thomas_os@shipmail.org>


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.

> @@ -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);