From patchwork Tue Mar 18 15:54:21 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Tvrtko Ursulin X-Patchwork-Id: 14021193 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 494FAC28B2F for ; Tue, 18 Mar 2025 15:54:39 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 7591810E21D; Tue, 18 Mar 2025 15:54:34 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=igalia.com header.i=@igalia.com header.b="gEq6rmNE"; dkim-atps=neutral Received: from fanzine2.igalia.com (fanzine.igalia.com [178.60.130.6]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8472610E4AB for ; Tue, 18 Mar 2025 15:54:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=igalia.com; s=20170329; h=Content-Transfer-Encoding:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=22c/VkFM9nfTdGKjjNkX+AayMdwXYVCgSlW96ygKRx8=; b=gEq6rmNElMRltUj8jOZantX09C gbiHx7Svzw9dqIQJyFeW61QsttqrhDpMp4sm0gemtvZ+lZeXAgryHmDjL7Xoxmq4YFJyC2JVAgBDr A3tFEMgsADi+T5M/g8p9FCpiFM5IDKaIdyyzqr57xTF3xPS4j8vNkLv9Gn3VKgRKOeN6OJLTTHcQl CfwIhuVhqHTZEjZEYKrq1jWFZafZmcu1hA9sNOgwt1DJ7Cz2X9eB8UXsuUJ8UUu8BPPNj7S/1kFb/ DjTjRquZ3TEZXpzv18z5rpCOneUI8WqtQVFYdjnZ/IPZtL/kTdQiosj73dJ8CmGVMjittqLP82XGT HaE2qmUA==; Received: from [90.241.98.187] (helo=localhost) by fanzine2.igalia.com with esmtpsa (Cipher TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim) id 1tuZGv-002ngq-Qb; Tue, 18 Mar 2025 16:54:29 +0100 From: Tvrtko Ursulin To: dri-devel@lists.freedesktop.org Cc: kernel-dev@igalia.com, Tvrtko Ursulin Subject: [PATCH 5/7] drm/syncobj: Avoid temporary allocation in drm_syncobj_timeline_signal_ioctl Date: Tue, 18 Mar 2025 15:54:21 +0000 Message-ID: <20250318155424.78552-6-tvrtko.ursulin@igalia.com> X-Mailer: git-send-email 2.48.0 In-Reply-To: <20250318155424.78552-1-tvrtko.ursulin@igalia.com> References: <20250318155424.78552-1-tvrtko.ursulin@igalia.com> MIME-Version: 1.0 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" We can avoid one of the two temporary allocations if we read the userspace supplied timeline points as we go along. The only new complication is to unwind unused fence chains on the error path, but even that code was already present in the function. Signed-off-by: Tvrtko Ursulin Reviewed-by: Maíra Canal --- drivers/gpu/drm/drm_syncobj.c | 46 +++++++++++++++-------------------- 1 file changed, 20 insertions(+), 26 deletions(-) diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c index 74d1dc0d1f8b..b4563c696056 100644 --- a/drivers/gpu/drm/drm_syncobj.c +++ b/drivers/gpu/drm/drm_syncobj.c @@ -1557,10 +1557,10 @@ drm_syncobj_timeline_signal_ioctl(struct drm_device *dev, void *data, struct drm_file *file_private) { struct drm_syncobj_timeline_array *args = data; + uint64_t __user *points = u64_to_user_ptr(args->points); + uint32_t i, j, count = args->count_handles; struct drm_syncobj **syncobjs; struct dma_fence_chain **chains; - uint64_t *points; - uint32_t i, j; int ret; if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE)) @@ -1572,33 +1572,22 @@ drm_syncobj_timeline_signal_ioctl(struct drm_device *dev, void *data, if (args->count_handles == 0) return -EINVAL; + if (!access_ok(points, count * sizeof(*points))) + return -EFAULT; + ret = drm_syncobj_array_find(file_private, u64_to_user_ptr(args->handles), - args->count_handles, + count, &syncobjs); if (ret < 0) return ret; - points = kmalloc_array(args->count_handles, sizeof(*points), - GFP_KERNEL); - if (!points) { - ret = -ENOMEM; - goto out; - } - if (!u64_to_user_ptr(args->points)) { - memset(points, 0, args->count_handles * sizeof(uint64_t)); - } else if (copy_from_user(points, u64_to_user_ptr(args->points), - sizeof(uint64_t) * args->count_handles)) { - ret = -EFAULT; - goto err_points; - } - - chains = kmalloc_array(args->count_handles, sizeof(void *), GFP_KERNEL); + chains = kmalloc_array(count, sizeof(void *), GFP_KERNEL); if (!chains) { ret = -ENOMEM; - goto err_points; + goto out; } - for (i = 0; i < args->count_handles; i++) { + for (i = 0; i < count; i++) { chains[i] = dma_fence_chain_alloc(); if (!chains[i]) { for (j = 0; j < i; j++) @@ -1608,19 +1597,24 @@ drm_syncobj_timeline_signal_ioctl(struct drm_device *dev, void *data, } } - for (i = 0; i < args->count_handles; i++) { + for (i = 0; i < count; i++) { struct dma_fence *fence = dma_fence_get_stub(); + u64 point = 0; - drm_syncobj_add_point(syncobjs[i], chains[i], - fence, points[i]); + if (points && __get_user(point, points++)) { + ret = -EFAULT; + for (j = i; j < count; j++) + dma_fence_chain_free(chains[j]); + goto err_chains; + } + + drm_syncobj_add_point(syncobjs[i], chains[i], fence, point); dma_fence_put(fence); } err_chains: kfree(chains); -err_points: - kfree(points); out: - drm_syncobj_array_free(syncobjs, args->count_handles); + drm_syncobj_array_free(syncobjs, count); return ret; }