From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A9494C433E7 for ; Fri, 9 Oct 2020 16:28:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5D42A22280 for ; Fri, 9 Oct 2020 16:28:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ffwll.ch header.i=@ffwll.ch header.b="bQX4adCP" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389797AbgJIQ2C (ORCPT ); Fri, 9 Oct 2020 12:28:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43754 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389144AbgJIQ2B (ORCPT ); Fri, 9 Oct 2020 12:28:01 -0400 Received: from mail-oo1-xc43.google.com (mail-oo1-xc43.google.com [IPv6:2607:f8b0:4864:20::c43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CC784C0613D2 for ; Fri, 9 Oct 2020 09:28:01 -0700 (PDT) Received: by mail-oo1-xc43.google.com with SMTP id w7so2500913oow.7 for ; Fri, 09 Oct 2020 09:28:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=FwD9qRck80aaS6hcwpVV+fGUUTa5tO1fSET+ZcHE9T8=; b=bQX4adCPHglu9tPk5eecC53IQeTGWv+EUOVCyYKo9uvRy4oEYH0nD+gAP2w+5nnP8B QlzdPV/9xf4H6eRw2kVrCXVQjh3aPSPtgDAAPdcSWJc1Spe5MOovBjYVYLXz0p3Oh4nT ofg2Zh9gTRaOVUMmYlegSOiljWKzfcI4G7PRY= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=FwD9qRck80aaS6hcwpVV+fGUUTa5tO1fSET+ZcHE9T8=; b=DMhhjbD/ZBcCK6r7jzD/xgziPDI21ivxoC4qecztsUpdM2L0Uyb7Z3M+2jFszlc9f3 ZEN5ZsmBHpX+feKS4/3H1GUc32l17wLKt589tAuO3QAIfHy1Tb6dzC6W5hoTe+Y289JB 6umVmup7YLTUsPKtx8VJvFkXmNCkBX7DUQe30b7526iGJ9JXTU2bpzoARVrzsWVMJ/sZ 6zLmtAt7z9gd/r/GqBGwHhiKK4SZh2ciSpdFAELbddnYDMeGcWS1LsHLnl19b6Z+R48B fYut6xHybhV4IkL5jhxOs9a5QiDKYljOfHnWqE5uPsDgkvNL+ZG56cU9mmyLftdbScD3 WRqA== X-Gm-Message-State: AOAM533H4CdZ4miijDPHd0bzTFnYyld10LPcXzTrdKmcHPeEgrofUXI8 nf9O98enmBO7cIlzUH0Fy5HF+uD+1koY66klPF66Tg== X-Google-Smtp-Source: ABdhPJzdQbwMUYb0ZFQJ3kLnpydd0XpR/r7Yz1OrUQs9NEMEBiryzok72FhSC53llTTytdAIzIrW3/i8SCIpf4/IZNY= X-Received: by 2002:a4a:c011:: with SMTP id v17mr9630277oop.89.1602260880414; Fri, 09 Oct 2020 09:28:00 -0700 (PDT) MIME-Version: 1.0 References: <20201009150342.1979-1-christian.koenig@amd.com> <20201009150342.1979-6-christian.koenig@amd.com> <20201009162444.GO438822@phenom.ffwll.local> In-Reply-To: <20201009162444.GO438822@phenom.ffwll.local> From: Daniel Vetter Date: Fri, 9 Oct 2020 18:27:49 +0200 Message-ID: Subject: Re: [PATCH 6/6] drm/prime: document that use the page array is deprecated v2 To: =?UTF-8?Q?Christian_K=C3=B6nig?= , Thomas Zimmermann Cc: Linux MM , Linux Kernel Mailing List , "moderated list:DMA BUFFER SHARING FRAMEWORK" , dri-devel , "open list:DMA BUFFER SHARING FRAMEWORK" , "Wilson, Chris" , Dave Airlie , Andrew Morton , Sumit Semwal , Matthew Wilcox , John Hubbard , Jason Gunthorpe Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org On Fri, Oct 9, 2020 at 6:24 PM Daniel Vetter wrote: > > On Fri, Oct 09, 2020 at 05:03:42PM +0200, Christian K=C3=B6nig wrote: > > We have reoccurring requests on this so better document that > > this approach doesn't work and dma_buf_mmap() needs to be used instead. > > > > v2: split it into two functions > > > > Signed-off-by: Christian K=C3=B6nig > > Patches 3-5: > > Acked-by: Daniel Vetter > > This one looks good, but you have it on a strange baseline. This doesn't > contain the sg walking fixes from Marek, so reintroduces the bugs. > Probably need to request a backmerge chain, first of -rc8 into drm-next, > and then that into drm-misc-next. Marek's patch is in drm-next, so just needs a backmerge into drm-misc-next. Thomas, can you pls do that? We need 0552daac2d18f I'll wait for the next round for patches 1&2 since Jason seems to have found a small issue with them. -Daniel > > Everything else in here lgtm. > -Daniel > > > > > --- > > drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 9 ++- > > drivers/gpu/drm/drm_prime.c | 67 +++++++++++++++------ > > drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c | 3 +- > > drivers/gpu/drm/msm/msm_gem.c | 2 +- > > drivers/gpu/drm/nouveau/nouveau_bo.c | 5 +- > > drivers/gpu/drm/radeon/radeon_ttm.c | 9 ++- > > drivers/gpu/drm/vgem/vgem_drv.c | 3 +- > > drivers/gpu/drm/vkms/vkms_gem.c | 2 +- > > drivers/gpu/drm/xen/xen_drm_front_gem.c | 4 +- > > include/drm/drm_prime.h | 7 ++- > > 10 files changed, 69 insertions(+), 42 deletions(-) > > > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/= amd/amdgpu/amdgpu_ttm.c > > index ac463e706b19..6a65490de391 100644 > > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c > > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c > > @@ -1011,8 +1011,8 @@ static int amdgpu_ttm_tt_pin_userptr(struct ttm_b= o_device *bdev, > > goto release_sg; > > > > /* convert SG to linear array of pages and dma addresses */ > > - drm_prime_sg_to_page_addr_arrays(ttm->sg, NULL, gtt->ttm.dma_addr= ess, > > - ttm->num_pages); > > + drm_prime_sg_to_dma_addr_array(ttm->sg, gtt->ttm.dma_address, > > + ttm->num_pages); > > > > return 0; > > > > @@ -1345,9 +1345,8 @@ static int amdgpu_ttm_tt_populate(struct ttm_bo_d= evice *bdev, > > ttm->sg =3D sgt; > > } > > > > - drm_prime_sg_to_page_addr_arrays(ttm->sg, NULL, > > - gtt->ttm.dma_address, > > - ttm->num_pages); > > + drm_prime_sg_to_dma_addr_array(ttm->sg, gtt->ttm.dma_addr= ess, > > + ttm->num_pages); > > ttm_tt_set_populated(ttm); > > return 0; > > } > > diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c > > index 4910c446db83..8b750c074494 100644 > > --- a/drivers/gpu/drm/drm_prime.c > > +++ b/drivers/gpu/drm/drm_prime.c > > @@ -954,27 +954,25 @@ struct drm_gem_object *drm_gem_prime_import(struc= t drm_device *dev, > > EXPORT_SYMBOL(drm_gem_prime_import); > > > > /** > > - * drm_prime_sg_to_page_addr_arrays - convert an sg table into a page = array > > + * drm_prime_sg_to_page_array - convert an sg table into a page array > > * @sgt: scatter-gather table to convert > > - * @pages: optional array of page pointers to store the page array in > > - * @addrs: optional array to store the dma bus address of each page > > - * @max_entries: size of both the passed-in arrays > > + * @pages: array of page pointers to store the pages in > > + * @max_entries: size of the passed-in array > > * > > - * Exports an sg table into an array of pages and addresses. This is c= urrently > > - * required by the TTM driver in order to do correct fault handling. > > + * Exports an sg table into an array of pages. > > * > > - * Drivers can use this in their &drm_driver.gem_prime_import_sg_table > > - * implementation. > > + * This function is deprecated and strongly discouraged to be used. > > + * The page array is only useful for page faults and those can corrupt= fields > > + * in the struct page if they are not handled by the exporting driver. > > */ > > -int drm_prime_sg_to_page_addr_arrays(struct sg_table *sgt, struct page= **pages, > > - dma_addr_t *addrs, int max_entries) > > +int __deprecated drm_prime_sg_to_page_array(struct sg_table *sgt, > > + struct page **pages, > > + int max_entries) > > { > > unsigned count; > > struct scatterlist *sg; > > struct page *page; > > u32 page_len, page_index; > > - dma_addr_t addr; > > - u32 dma_len, dma_index; > > > > /* > > * Scatterlist elements contains both pages and DMA addresses, bu= t > > @@ -984,14 +982,11 @@ int drm_prime_sg_to_page_addr_arrays(struct sg_ta= ble *sgt, struct page **pages, > > * described by the sg_dma_address(sg). > > */ > > page_index =3D 0; > > - dma_index =3D 0; > > for_each_sg(sgt->sgl, sg, sgt->nents, count) { > > page_len =3D sg->length; > > page =3D sg_page(sg); > > - dma_len =3D sg_dma_len(sg); > > - addr =3D sg_dma_address(sg); > > > > - while (pages && page_len > 0) { > > + while (page_len > 0) { > > if (WARN_ON(page_index >=3D max_entries)) > > return -1; > > pages[page_index] =3D page; > > @@ -999,7 +994,43 @@ int drm_prime_sg_to_page_addr_arrays(struct sg_tab= le *sgt, struct page **pages, > > page_len -=3D PAGE_SIZE; > > page_index++; > > } > > - while (addrs && dma_len > 0) { > > + } > > + return 0; > > +} > > +EXPORT_SYMBOL(drm_prime_sg_to_page_array); > > + > > +/** > > + * drm_prime_sg_to_dma_addr_array - convert an sg table into a dma add= r array > > + * @sgt: scatter-gather table to convert > > + * @addrs: array to store the dma bus address of each page > > + * @max_entries: size of both the passed-in arrays > > + * > > + * Exports an sg table into an array of addresses. > > + * > > + * Drivers should use this in their &drm_driver.gem_prime_import_sg_ta= ble > > s/should/can/ > > There's no requirement, if your driver just handles everything as an sgt > there's no conversion needed. > > > + * implementation. > > + */ > > +int drm_prime_sg_to_dma_addr_array(struct sg_table *sgt, dma_addr_t *a= ddrs, > > + int max_entries) > > +{ > > + struct scatterlist *sg; > > + u32 dma_len, dma_index; > > + dma_addr_t addr; > > + unsigned count; > > + > > + /* > > + * Scatterlist elements contains both pages and DMA addresses, bu= t > > + * one shoud not assume 1:1 relation between them. The sg->length= is > > + * the size of the physical memory chunk described by the sg->pag= e, > > + * while sg_dma_len(sg) is the size of the DMA (IO virtual) chunk > > + * described by the sg_dma_address(sg). > > + */ > > + dma_index =3D 0; > > + for_each_sg(sgt->sgl, sg, sgt->nents, count) { > > + dma_len =3D sg_dma_len(sg); > > + addr =3D sg_dma_address(sg); > > + > > + while (dma_len > 0) { > > if (WARN_ON(dma_index >=3D max_entries)) > > return -1; > > addrs[dma_index] =3D addr; > > @@ -1010,7 +1041,7 @@ int drm_prime_sg_to_page_addr_arrays(struct sg_ta= ble *sgt, struct page **pages, > > } > > return 0; > > } > > -EXPORT_SYMBOL(drm_prime_sg_to_page_addr_arrays); > > +EXPORT_SYMBOL(drm_prime_sg_to_dma_addr_array); > > > > /** > > * drm_prime_gem_destroy - helper to clean up a PRIME-imported GEM obj= ect > > diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c b/drivers/gpu/= drm/etnaviv/etnaviv_gem_prime.c > > index 135fbff6fecf..8c04b8e8054c 100644 > > --- a/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c > > +++ b/drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c > > @@ -133,8 +133,7 @@ struct drm_gem_object *etnaviv_gem_prime_import_sg_= table(struct drm_device *dev, > > goto fail; > > } > > > > - ret =3D drm_prime_sg_to_page_addr_arrays(sgt, etnaviv_obj->pages, > > - NULL, npages); > > + ret =3D drm_prime_sg_to_page_array(sgt, etnaviv_obj->pages, npage= s); > > if (ret) > > goto fail; > > > > diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_ge= m.c > > index a71f42870d5e..616b87641740 100644 > > --- a/drivers/gpu/drm/msm/msm_gem.c > > +++ b/drivers/gpu/drm/msm/msm_gem.c > > @@ -1174,7 +1174,7 @@ struct drm_gem_object *msm_gem_import(struct drm_= device *dev, > > goto fail; > > } > > > > - ret =3D drm_prime_sg_to_page_addr_arrays(sgt, msm_obj->pages, NUL= L, npages); > > + ret =3D drm_prime_sg_to_page_array(sgt, msm_obj->pages, npages); > > if (ret) { > > mutex_unlock(&msm_obj->lock); > > goto fail; > > diff --git a/drivers/gpu/drm/nouveau/nouveau_bo.c b/drivers/gpu/drm/nou= veau/nouveau_bo.c > > index e378bb491688..835edd74ef59 100644 > > --- a/drivers/gpu/drm/nouveau/nouveau_bo.c > > +++ b/drivers/gpu/drm/nouveau/nouveau_bo.c > > @@ -1299,9 +1299,8 @@ nouveau_ttm_tt_populate(struct ttm_bo_device *bde= v, > > return 0; > > > > if (slave && ttm->sg) { > > - drm_prime_sg_to_page_addr_arrays(ttm->sg, NULL, > > - ttm_dma->dma_address, > > - ttm->num_pages); > > + drm_prime_sg_to_dma_addr_array(ttm->sg, ttm_dma->dma_addr= ess, > > + ttm->num_pages); > > ttm_tt_set_populated(ttm); > > return 0; > > } > > diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/rade= on/radeon_ttm.c > > index 4b92cdbcd29b..7997e4564576 100644 > > --- a/drivers/gpu/drm/radeon/radeon_ttm.c > > +++ b/drivers/gpu/drm/radeon/radeon_ttm.c > > @@ -474,8 +474,8 @@ static int radeon_ttm_tt_pin_userptr(struct ttm_bo_= device *bdev, struct ttm_tt * > > if (r) > > goto release_sg; > > > > - drm_prime_sg_to_page_addr_arrays(ttm->sg, NULL, gtt->ttm.dma_addr= ess, > > - ttm->num_pages); > > + drm_prime_sg_to_dma_addr_array(ttm->sg, gtt->ttm.dma_address, > > + ttm->num_pages); > > > > return 0; > > > > @@ -642,9 +642,8 @@ static int radeon_ttm_tt_populate(struct ttm_bo_dev= ice *bdev, > > } > > > > if (slave && ttm->sg) { > > - drm_prime_sg_to_page_addr_arrays(ttm->sg, NULL, > > - gtt->ttm.dma_address, > > - ttm->num_pages); > > + drm_prime_sg_to_dma_addr_array(ttm->sg, gtt->ttm.dma_addr= ess, > > + ttm->num_pages); > > ttm_tt_set_populated(ttm); > > return 0; > > } > > diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vge= m_drv.c > > index ea0eecae5153..e505e5a291b3 100644 > > --- a/drivers/gpu/drm/vgem/vgem_drv.c > > +++ b/drivers/gpu/drm/vgem/vgem_drv.c > > @@ -356,8 +356,7 @@ static struct drm_gem_object *vgem_prime_import_sg_= table(struct drm_device *dev, > > } > > > > obj->pages_pin_count++; /* perma-pinned */ > > - drm_prime_sg_to_page_addr_arrays(obj->table, obj->pages, NULL, > > - npages); > > + drm_prime_sg_to_page_array(obj->table, obj->pages, npages); > > return &obj->base; > > } > > > > diff --git a/drivers/gpu/drm/vkms/vkms_gem.c b/drivers/gpu/drm/vkms/vkm= s_gem.c > > index 19a0e260a4df..a2ff21f47101 100644 > > --- a/drivers/gpu/drm/vkms/vkms_gem.c > > +++ b/drivers/gpu/drm/vkms/vkms_gem.c > > @@ -256,6 +256,6 @@ vkms_prime_import_sg_table(struct drm_device *dev, > > return ERR_PTR(-ENOMEM); > > } > > > > - drm_prime_sg_to_page_addr_arrays(sg, obj->pages, NULL, npages); > > + drm_prime_sg_to_page_array(sg, obj->pages, npages); > > return &obj->gem; > > } > > diff --git a/drivers/gpu/drm/xen/xen_drm_front_gem.c b/drivers/gpu/drm/= xen/xen_drm_front_gem.c > > index f3830a0d1808..f4150ddfc5e2 100644 > > --- a/drivers/gpu/drm/xen/xen_drm_front_gem.c > > +++ b/drivers/gpu/drm/xen/xen_drm_front_gem.c > > @@ -220,8 +220,8 @@ xen_drm_front_gem_import_sg_table(struct drm_device= *dev, > > > > xen_obj->sgt_imported =3D sgt; > > > > - ret =3D drm_prime_sg_to_page_addr_arrays(sgt, xen_obj->pages, > > - NULL, xen_obj->num_pages); > > + ret =3D drm_prime_sg_to_page_array(sgt, xen_obj->pages, > > + xen_obj->num_pages); > > if (ret < 0) > > return ERR_PTR(ret); > > > > diff --git a/include/drm/drm_prime.h b/include/drm/drm_prime.h > > index 093f760cc131..4bda9ab3a3bb 100644 > > --- a/include/drm/drm_prime.h > > +++ b/include/drm/drm_prime.h > > @@ -103,8 +103,9 @@ struct drm_gem_object *drm_gem_prime_import(struct = drm_device *dev, > > > > void drm_prime_gem_destroy(struct drm_gem_object *obj, struct sg_table= *sg); > > > > -int drm_prime_sg_to_page_addr_arrays(struct sg_table *sgt, struct page= **pages, > > - dma_addr_t *addrs, int max_pages); > > - > > +int drm_prime_sg_to_page_array(struct sg_table *sgt, struct page **pag= es, > > + int max_pages); > > +int drm_prime_sg_to_dma_addr_array(struct sg_table *sgt, dma_addr_t *a= ddrs, > > + int max_pages); > > > > #endif /* __DRM_PRIME_H__ */ > > -- > > 2.17.1 > > > > -- > Daniel Vetter > Software Engineer, Intel Corporation > http://blog.ffwll.ch --=20 Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch