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Subject: RE: [PATCH v8 1/8] mm/memfd: Introduce userspace inaccessible memfd
Thread-Topic: [PATCH v8 1/8] mm/memfd: Introduce userspace inaccessible memfd
Thread-Index: AQHYyRA+DGITW09wp06ZhgFK30MXVK3mRmjw
Date:   Thu, 22 Sep 2022 13:26:47 +0000
Message-ID: <DS0PR11MB63734D4DF4C4F368805EC97DDC4E9@DS0PR11MB6373.namprd11.prod.outlook.com>
References: <20220915142913.2213336-1-chao.p.peng@linux.intel.com>
 <20220915142913.2213336-2-chao.p.peng@linux.intel.com>
In-Reply-To: <20220915142913.2213336-2-chao.p.peng@linux.intel.com>
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On Thursday, September 15, 2022 10:29 PM, Chao Peng wrote:
> +int inaccessible_get_pfn(struct file *file, pgoff_t offset, pfn_t *pfn,
> +			 int *order)

Better to remove "order" from this interface?
Some callers only need to get pfn, and no need to bother with
defining and inputting something unused. For callers who need the "order",
can easily get it via thp_order(pfn_to_page(pfn)) on their own.