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 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A7CB3C369B2 for ; Thu, 17 Apr 2025 10:16:02 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 19C7A10EA87; Thu, 17 Apr 2025 10:16:02 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=collabora.com header.i=@collabora.com header.b="AkMk+1Sq"; dkim-atps=neutral Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) by gabe.freedesktop.org (Postfix) with ESMTPS id 623AA10EA87 for ; Thu, 17 Apr 2025 10:16:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1744884958; bh=KaFbT2y75wQCpnjdD8pO/AdOtEhqFUmgseXs/CwLJDM=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=AkMk+1SqwJDhYf3wl1KhokOkifx9oxphFKkiLsL73Qauj2JyHevVEk0xI9vR0bzI3 BnPqMjcIrZ2dxfiXXdppQC7JnGZ0zPQhhpsDQVBN48ksToKnVVysv3RkYreuZvn3aH ffXgU5Lvn62WSwgAUXfJLpWQKUrT6O34Aav75xEC6X4WnooYK8LeJrVdzVtzCS3Jla 7JT4RmVvXRWztnUV/hbjfU+SSiTL/amkRsxBi6ysxacMGhGtmJWvezXmqsRoHdgwLG mn4P/liDCIlj1WHke4rUV70gf7n7GRMTmQ23EruU0bXbSnzk25t937NYyUw2WA97/9 yzvj6j+HilYfA== Received: from localhost (unknown [IPv6:2a01:e0a:2c:6930:5cf4:84a1:2763:fe0d]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: bbrezillon) by bali.collaboradmins.com (Postfix) with ESMTPSA id 9C36717E08E3; Thu, 17 Apr 2025 12:15:58 +0200 (CEST) Date: Thu, 17 Apr 2025 12:15:54 +0200 From: Boris Brezillon To: Matthew Auld Cc: Steven Price , Liviu Dudau , =?UTF-8?B?QWRyacOhbg==?= Larumbe , dri-devel@lists.freedesktop.org, kernel@collabora.com Subject: Re: [PATCH v2] drm/panthor: Don't create a file offset for NO_MMAP BOs Message-ID: <20250417121554.5a9ca8ff@collabora.com> In-Reply-To: <4b14aba4-b9e6-436e-9027-4a3f6a6c7daf@intel.com> References: <20250417093247.3455096-1-boris.brezillon@collabora.com> <4b14aba4-b9e6-436e-9027-4a3f6a6c7daf@intel.com> Organization: Collabora X-Mailer: Claws Mail 4.3.0 (GTK 3.24.43; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Thu, 17 Apr 2025 10:53:23 +0100 Matthew Auld wrote: > On 17/04/2025 10:32, Boris Brezillon wrote: > > Right now the DRM_PANTHOR_BO_NO_MMAP flag is ignored by > > panthor_ioctl_bo_mmap_offset(), meaning BOs with this flag set can > > have a file offset but can't be mapped anyway, because > > panthor_gem_mmap() will filter them out. > > > > If we error out at mmap_offset creation time, we can get rid of > > panthor_gem_mmap() and call drm_gem_shmem_object_mmap directly, and > > we get rid of this inconsistency of having an mmap offset for a > > BO that can never be mmap-ed. > > > > Changes in v2: > > - Get rid of panthor_gem_mmap() > > - Get rid of the Fixes tag and adjust the commit message accordingly > > - Return ENOPERM instead of EINVAL > > > > Signed-off-by: Boris Brezillon > > --- > > drivers/gpu/drm/panthor/panthor_drv.c | 5 +++++ > > drivers/gpu/drm/panthor/panthor_gem.c | 13 +------------ > > 2 files changed, 6 insertions(+), 12 deletions(-) > > > > diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/panthor/panthor_drv.c > > index 06fe46e32073..7cd131af340d 100644 > > --- a/drivers/gpu/drm/panthor/panthor_drv.c > > +++ b/drivers/gpu/drm/panthor/panthor_drv.c > > @@ -940,6 +940,7 @@ static int panthor_ioctl_bo_mmap_offset(struct drm_device *ddev, void *data, > > struct drm_file *file) > > { > > struct drm_panthor_bo_mmap_offset *args = data; > > + struct panthor_gem_object *bo; > > struct drm_gem_object *obj; > > int ret; > > > > @@ -950,6 +951,10 @@ static int panthor_ioctl_bo_mmap_offset(struct drm_device *ddev, void *data, > > if (!obj) > > return -ENOENT; > > > > + bo = to_panthor_bo(obj); > > + if (bo->flags & DRM_PANTHOR_BO_NO_MMAP) > > + return -EPERM; > > Just a drive-by-comment: are we not leaking the bo ref here? We certainly are, good catch! > > > + > > ret = drm_gem_create_mmap_offset(obj); > > if (ret) > > goto out; > > diff --git a/drivers/gpu/drm/panthor/panthor_gem.c b/drivers/gpu/drm/panthor/panthor_gem.c > > index fd014ccc3bfc..22d78cef9c66 100644 > > --- a/drivers/gpu/drm/panthor/panthor_gem.c > > +++ b/drivers/gpu/drm/panthor/panthor_gem.c > > @@ -129,17 +129,6 @@ panthor_kernel_bo_create(struct panthor_device *ptdev, struct panthor_vm *vm, > > return ERR_PTR(ret); > > } > > > > -static int panthor_gem_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma) > > -{ > > - struct panthor_gem_object *bo = to_panthor_bo(obj); > > - > > - /* Don't allow mmap on objects that have the NO_MMAP flag set. */ > > - if (bo->flags & DRM_PANTHOR_BO_NO_MMAP) > > - return -EINVAL; > > - > > - return drm_gem_shmem_object_mmap(obj, vma); > > -} > > - > > static struct dma_buf * > > panthor_gem_prime_export(struct drm_gem_object *obj, int flags) > > { > > @@ -169,7 +158,7 @@ static const struct drm_gem_object_funcs panthor_gem_funcs = { > > .get_sg_table = drm_gem_shmem_object_get_sg_table, > > .vmap = drm_gem_shmem_object_vmap, > > .vunmap = drm_gem_shmem_object_vunmap, > > - .mmap = panthor_gem_mmap, > > + .mmap = drm_gem_shmem_object_mmap, > > .status = panthor_gem_status, > > .export = panthor_gem_prime_export, > > .vm_ops = &drm_gem_shmem_vm_ops, >