From patchwork Tue Nov 3 09:27:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 11879839 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=-6.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 AC41CC388F7 for ; Wed, 4 Nov 2020 08:22:52 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 4B42B20781 for ; Wed, 4 Nov 2020 08:22:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="cAh//GKs"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="FQTjFZ+Z" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4B42B20781 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linutronix.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E12B4895B5; Wed, 4 Nov 2020 08:22:15 +0000 (UTC) Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) by gabe.freedesktop.org (Postfix) with ESMTPS id 3AD2A6EC5E; Tue, 3 Nov 2020 10:34:11 +0000 (UTC) Message-Id: <20201103095859.836711767@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1604399643; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: references:references; bh=yUxHC0cakBFRwhud8xMOIDvuAaJvgwuFtrBz27XdsEs=; b=cAh//GKsz39P8xqXnJcqDaA3W/edzWVdAqwjKoXA5Js/x368VRmdM0h2fj6bQZPAll8hmr yl8q8CcCNvb+2SfFaIo7cnx8vW2iPoTlWRNGNB06KJ1ERTQlqVwbp+qakHsf3DKm3O66rB +8+R2pAlCb2SMbZCBSyvPjBwiK1AVT7Wn6TtWs6GsMiR2cmkq8EcpYI90/EI8cGq7Q0K6k PWjm7m4uZQ4xtBGqzKEndSPHHSWqIlOOUtSiYkKMXa6yxfM8jl2K7omhkCJJofz/LjfJ5M Q/MfbNPI/NbAKfCFzA8vjy9XJtarFWdneKuOU4n/OP2w4gxAPRJI0FNbRKwq8Q== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1604399643; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: references:references; bh=yUxHC0cakBFRwhud8xMOIDvuAaJvgwuFtrBz27XdsEs=; b=FQTjFZ+ZYdRELu4iTMN0YYBNgOsOxBJVlxyxuynko9bscI/OxppLps2A/EThS2XSvqYRg0 nAwEXgV5JRubDDDA== Date: Tue, 03 Nov 2020 10:27:44 +0100 From: Thomas Gleixner To: LKML Subject: [patch V3 32/37] drm/vmgfx: Replace kmap_atomic() References: <20201103092712.714480842@linutronix.de> MIME-Version: 1.0 X-Mailman-Approved-At: Wed, 04 Nov 2020 08:22:13 +0000 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: , Cc: Juri Lelli , linux-aio@kvack.org, Peter Zijlstra , Sebastian Andrzej Siewior , dri-devel@lists.freedesktop.org, virtualization@lists.linux-foundation.org, Ben Segall , linux-mm@kvack.org, Huang Rui , Paul Mackerras , Gerd Hoffmann , Daniel Bristot de Oliveira , sparclinux@vger.kernel.org, Vincent Chen , Christoph Hellwig , Vincent Guittot , Arnd Bergmann , Max Filippov , Michael Ellerman , x86@kernel.org, Russell King , linux-csky@vger.kernel.org, Ingo Molnar , David Airlie , VMware Graphics , Mel Gorman , nouveau@lists.freedesktop.org, Dave Airlie , linux-snps-arc@lists.infradead.org, Ben Skeggs , linux-xtensa@linux-xtensa.org, Paul McKenney , intel-gfx@lists.freedesktop.org, Roland Scheidegger , Josef Bacik , Steven Rostedt , Linus Torvalds , Alexander Viro , spice-devel@lists.freedesktop.org, David Sterba , Rodrigo Vivi , Dietmar Eggemann , linux-arm-kernel@lists.infradead.org, Chris Zankel , Michal Simek , Thomas Bogendoerfer , Nick Hu , Chris Mason , Vineet Gupta , linux-mips@vger.kernel.org, Christian Koenig , Benjamin LaHaise , linux-fsdevel@vger.kernel.org, Andrew Morton , linuxppc-dev@lists.ozlabs.org, "David S. Miller" , linux-btrfs@vger.kernel.org, Greentime Hu Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" There is no reason to disable pagefaults and preemption as a side effect of kmap_atomic_prot(). Use kmap_local_page_prot() instead and document the reasoning for the mapping usage with the given pgprot. Remove the NULL pointer check for the map. These functions return a valid address for valid pages and the return was bogus anyway as it would have left preemption and pagefaults disabled. Signed-off-by: Thomas Gleixner Cc: VMware Graphics Cc: Roland Scheidegger Cc: David Airlie Cc: Daniel Vetter Cc: dri-devel@lists.freedesktop.org --- V3: New patch --- drivers/gpu/drm/vmwgfx/vmwgfx_blit.c | 30 ++++++++++++------------------ 1 file changed, 12 insertions(+), 18 deletions(-) --- a/drivers/gpu/drm/vmwgfx/vmwgfx_blit.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_blit.c @@ -375,12 +375,12 @@ static int vmw_bo_cpu_blit_line(struct v copy_size = min_t(u32, copy_size, PAGE_SIZE - src_page_offset); if (unmap_src) { - kunmap_atomic(d->src_addr); + kunmap_local(d->src_addr); d->src_addr = NULL; } if (unmap_dst) { - kunmap_atomic(d->dst_addr); + kunmap_local(d->dst_addr); d->dst_addr = NULL; } @@ -388,12 +388,8 @@ static int vmw_bo_cpu_blit_line(struct v if (WARN_ON_ONCE(dst_page >= d->dst_num_pages)) return -EINVAL; - d->dst_addr = - kmap_atomic_prot(d->dst_pages[dst_page], - d->dst_prot); - if (!d->dst_addr) - return -ENOMEM; - + d->dst_addr = kmap_local_page_prot(d->dst_pages[dst_page], + d->dst_prot); d->mapped_dst = dst_page; } @@ -401,12 +397,8 @@ static int vmw_bo_cpu_blit_line(struct v if (WARN_ON_ONCE(src_page >= d->src_num_pages)) return -EINVAL; - d->src_addr = - kmap_atomic_prot(d->src_pages[src_page], - d->src_prot); - if (!d->src_addr) - return -ENOMEM; - + d->src_addr = kmap_local_page_prot(d->src_pages[src_page], + d->src_prot); d->mapped_src = src_page; } diff->do_cpy(diff, d->dst_addr + dst_page_offset, @@ -436,8 +428,10 @@ static int vmw_bo_cpu_blit_line(struct v * * Performs a CPU blit from one buffer object to another avoiding a full * bo vmap which may exhaust- or fragment vmalloc space. - * On supported architectures (x86), we're using kmap_atomic which avoids - * cross-processor TLB- and cache flushes and may, on non-HIGHMEM systems + * + * On supported architectures (x86), we're using kmap_local_prot() which + * avoids cross-processor TLB- and cache flushes. kmap_local_prot() will + * either map a highmem page with the proper pgprot on HIGHMEM=y systems or * reference already set-up mappings. * * Neither of the buffer objects may be placed in PCI memory @@ -500,9 +494,9 @@ int vmw_bo_cpu_blit(struct ttm_buffer_ob } out: if (d.src_addr) - kunmap_atomic(d.src_addr); + kunmap_local(d.src_addr); if (d.dst_addr) - kunmap_atomic(d.dst_addr); + kunmap_local(d.dst_addr); return ret; }