From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Rapoport Subject: Re: [PATCH 1/9] mm: Introduce new vm_insert_range API Date: Fri, 23 Nov 2018 09:19:25 +0200 Message-ID: <20181123071924.GF5704@rapoport-lnx> References: <20181115154530.GA27872@jordon-HP-15-Notebook-PC> <20181116182836.GB17088@rapoport-lnx> <20181117143742.GB7861@bombadil.infradead.org> <20181119162623.GA13200@rapoport-lnx> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Souptick Joarder Cc: Michal Hocko , Heiko Stuebner , Peter Zijlstra , dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Linux-MM , linux1394-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, Stephen Rothwell , oleksandr_andrushchenko-uRwfk40T5oI@public.gmane.org, Russell King - ARM Linux , Matthew Wilcox , airlied-cv59FeDIM0c@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, treding-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org, linux-media-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Kees Cook , pawel-FA/gS7QP4orQT0dZR+AlfA@public.gmane.org, Rik van Riel , iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, rppt-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org, Boris Ostrovsky , mchehab-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, iamjoonsoo.kim-Hm3cg6mZ9cc@public.gmane.org, vbabka-AlSwsSmVLrQ@public.gmane.org, Juergen Gross , hjc-TNX95d0MmH7DzftRWevZcw@public.gmane.org, xen-devel-GuqFBffKawuEi8DpZVb4nw@public.gmane.org, Kyungmin List-Id: linux-rockchip.vger.kernel.org On Mon, Nov 19, 2018 at 11:15:15PM +0530, Souptick Joarder wrote: > On Mon, Nov 19, 2018 at 9:56 PM Mike Rapoport wrote: > > > > On Mon, Nov 19, 2018 at 08:43:09PM +0530, Souptick Joarder wrote: > > > Hi Mike, > > > > > > On Sat, Nov 17, 2018 at 8:07 PM Matthew Wilcox wrote: > > > > > > > > On Sat, Nov 17, 2018 at 12:26:38PM +0530, Souptick Joarder wrote: > > > > > On Fri, Nov 16, 2018 at 11:59 PM Mike Rapoport wrote: > > > > > > > + * vm_insert_range - insert range of kernel pages into user vma > > > > > > > + * @vma: user vma to map to > > > > > > > + * @addr: target user address of this page > > > > > > > + * @pages: pointer to array of source kernel pages > > > > > > > + * @page_count: no. of pages need to insert into user vma > > > > > > > + * > > > > > > > + * This allows drivers to insert range of kernel pages they've allocated > > > > > > > + * into a user vma. This is a generic function which drivers can use > > > > > > > + * rather than using their own way of mapping range of kernel pages into > > > > > > > + * user vma. > > > > > > > > > > > > Please add the return value and context descriptions. > > > > > > > > > > > > > > > > Sure I will wait for some time to get additional review comments and > > > > > add all of those requested changes in v2. > > > > > > > > You could send your proposed wording now which might remove the need > > > > for a v3 if we end up arguing about the wording. > > > > > > Does this description looks good ? > > > > > > /** > > > * vm_insert_range - insert range of kernel pages into user vma > > > * @vma: user vma to map to > > > * @addr: target user address of this page > > > * @pages: pointer to array of source kernel pages > > > * @page_count: number of pages need to insert into user vma > > > * > > > * This allows drivers to insert range of kernel pages they've allocated > > > * into a user vma. This is a generic function which drivers can use > > > * rather than using their own way of mapping range of kernel pages into > > > * user vma. > > > * > > > * Context - Process context. Called by mmap handlers. > > > > Context: > > > > > * Return - int error value > > > > Return: > > > > > * 0 - OK > > > * -EINVAL - Invalid argument > > > * -ENOMEM - No memory > > > * -EFAULT - Bad address > > > * -EBUSY - Device or resource busy > > > > I don't think that elaborate description of error values is needed, just "0 > > on success and error code otherwise" would be sufficient. > > /** > * vm_insert_range - insert range of kernel pages into user vma > * @vma: user vma to map to > * @addr: target user address of this page > * @pages: pointer to array of source kernel pages > * @page_count: number of pages need to insert into user vma > * > * This allows drivers to insert range of kernel pages they've allocated > * into a user vma. This is a generic function which drivers can use > * rather than using their own way of mapping range of kernel pages into > * user vma. > * > * Context: Process context. Called by mmap handlers. > * Return: 0 on success and error code otherwise > */ Looks good to me. -- Sincerely yours, Mike.