From patchwork Tue Nov 3 09:27:49 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 11876939 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=-6.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 086BBC82617 for ; Tue, 3 Nov 2020 10:34:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A949822404 for ; Tue, 3 Nov 2020 10:34:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="CdqukbVB"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="pfa+TpRf" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728614AbgKCKeX (ORCPT ); Tue, 3 Nov 2020 05:34:23 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38622 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728607AbgKCKeT (ORCPT ); Tue, 3 Nov 2020 05:34:19 -0500 Received: from galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 90C1BC0613D1; Tue, 3 Nov 2020 02:34:18 -0800 (PST) Message-Id: <20201103095900.367260321@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1604399649; 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=XzZnXq40Xta6eAd8+Z4XomSn8j1A2hSECk29QnRRbws=; b=CdqukbVBWMYI/RONrhSGzX6/xMHlDVBTWtfJrQb8BGeECEJqjOAzrpgd/S5gcYhw2K5fbn Eaab3vE9c+BoonfV0tN18iO2mipbe36uJxmY7lt1Q+Y/DUZ/Lt4ranrEwz1e8nCX8rE7ib zUEarU65A2JKzY8kRhVSr0Mov+N333GuC6WgQoQRke1a5GsVBT4qs+q/yyCNm0M0BVOUKi wwWaobx9qhLoUV9tFHktWx+AG8+ArEEhZ4OLWEEinwZC+qMmqYYw2bnvpObjtaVxDm8Ir6 h+E3LFBQps2vHJjH1B0mTeQMdmzvDlwqg7xu3fUjiEVpzfRq4Nob09i6lYhuzA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1604399649; 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=XzZnXq40Xta6eAd8+Z4XomSn8j1A2hSECk29QnRRbws=; b=pfa+TpRfmsyoL3kfRqJUVU2S9UUvIXMBP/3UXjO0TEtWrbhDCiNU865DGow3SSMVJwemxu 95CKXmp2zPH8LuBg== Date: Tue, 03 Nov 2020 10:27:49 +0100 From: Thomas Gleixner To: LKML Cc: Linus Torvalds , Peter Zijlstra , Paul McKenney , Christoph Hellwig , Sebastian Andrzej Siewior , Andrew Morton , linux-mm@kvack.org, Alexander Viro , Benjamin LaHaise , linux-fsdevel@vger.kernel.org, linux-aio@kvack.org, Chris Mason , Josef Bacik , David Sterba , linux-btrfs@vger.kernel.org, x86@kernel.org, Vineet Gupta , linux-snps-arc@lists.infradead.org, Russell King , Arnd Bergmann , linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, Michal Simek , Thomas Bogendoerfer , linux-mips@vger.kernel.org, Nick Hu , Greentime Hu , Vincent Chen , Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , linuxppc-dev@lists.ozlabs.org, "David S. Miller" , sparclinux@vger.kernel.org, Chris Zankel , Max Filippov , linux-xtensa@linux-xtensa.org, Ingo Molnar , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Daniel Bristot de Oliveira , Christian Koenig , Huang Rui , David Airlie , Daniel Vetter , dri-devel@lists.freedesktop.org, VMware Graphics , Roland Scheidegger , Dave Airlie , Gerd Hoffmann , virtualization@lists.linux-foundation.org, spice-devel@lists.freedesktop.org, Ben Skeggs , nouveau@lists.freedesktop.org, Jani Nikula , Joonas Lahtinen , Rodrigo Vivi , intel-gfx@lists.freedesktop.org Subject: [patch V3 37/37] io-mapping: Remove io_mapping_map_atomic_wc() References: <20201103092712.714480842@linutronix.de> MIME-Version: 1.0 Content-transfer-encoding: 8-bit Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org No more users. Get rid of it and remove the traces in documentation. Signed-off-by: Thomas Gleixner --- V3: New patch --- Documentation/driver-api/io-mapping.rst | 22 +++++----------- include/linux/io-mapping.h | 42 +------------------------------- 2 files changed, 9 insertions(+), 55 deletions(-) --- a/Documentation/driver-api/io-mapping.rst +++ b/Documentation/driver-api/io-mapping.rst @@ -21,19 +21,15 @@ mappable, while 'size' indicates how lar enable. Both are in bytes. This _wc variant provides a mapping which may only be used with -io_mapping_map_atomic_wc(), io_mapping_map_local_wc() or -io_mapping_map_wc(). +io_mapping_map_local_wc() or io_mapping_map_wc(). With this mapping object, individual pages can be mapped either temporarily or long term, depending on the requirements. Of course, temporary maps are -more efficient. They come in two flavours:: +more efficient. void *io_mapping_map_local_wc(struct io_mapping *mapping, unsigned long offset) - void *io_mapping_map_atomic_wc(struct io_mapping *mapping, - unsigned long offset) - 'offset' is the offset within the defined mapping region. Accessing addresses beyond the region specified in the creation function yields undefined results. Using an offset which is not page aligned yields an @@ -50,9 +46,6 @@ io_mapping_map_local_wc() has a side eff migration to make the mapping code work. No caller can rely on this side effect. -io_mapping_map_atomic_wc() has the side effect of disabling preemption and -pagefaults. Don't use in new code. Use io_mapping_map_local_wc() instead. - Nested mappings need to be undone in reverse order because the mapping code uses a stack for keeping track of them:: @@ -65,11 +58,10 @@ Nested mappings need to be undone in rev The mappings are released with:: void io_mapping_unmap_local(void *vaddr) - void io_mapping_unmap_atomic(void *vaddr) -'vaddr' must be the value returned by the last io_mapping_map_local_wc() or -io_mapping_map_atomic_wc() call. This unmaps the specified mapping and -undoes the side effects of the mapping functions. +'vaddr' must be the value returned by the last io_mapping_map_local_wc() +call. This unmaps the specified mapping and undoes eventual side effects of +the mapping function. If you need to sleep while holding a mapping, you can use the regular variant, although this may be significantly slower:: @@ -77,8 +69,8 @@ If you need to sleep while holding a map void *io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset) -This works like io_mapping_map_atomic/local_wc() except it has no side -effects and the pointer is globaly visible. +This works like io_mapping_map_local_wc() except it has no side effects and +the pointer is globaly visible. The mappings are released with:: --- a/include/linux/io-mapping.h +++ b/include/linux/io-mapping.h @@ -60,28 +60,7 @@ io_mapping_fini(struct io_mapping *mappi iomap_free(mapping->base, mapping->size); } -/* Atomic map/unmap */ -static inline void __iomem * -io_mapping_map_atomic_wc(struct io_mapping *mapping, - unsigned long offset) -{ - resource_size_t phys_addr; - - BUG_ON(offset >= mapping->size); - phys_addr = mapping->base + offset; - preempt_disable(); - pagefault_disable(); - return __iomap_local_pfn_prot(PHYS_PFN(phys_addr), mapping->prot); -} - -static inline void -io_mapping_unmap_atomic(void __iomem *vaddr) -{ - kunmap_local_indexed((void __force *)vaddr); - pagefault_enable(); - preempt_enable(); -} - +/* Temporary mappings which are only valid in the current context */ static inline void __iomem * io_mapping_map_local_wc(struct io_mapping *mapping, unsigned long offset) { @@ -163,24 +142,7 @@ io_mapping_unmap(void __iomem *vaddr) { } -/* Atomic map/unmap */ -static inline void __iomem * -io_mapping_map_atomic_wc(struct io_mapping *mapping, - unsigned long offset) -{ - preempt_disable(); - pagefault_disable(); - return io_mapping_map_wc(mapping, offset, PAGE_SIZE); -} - -static inline void -io_mapping_unmap_atomic(void __iomem *vaddr) -{ - io_mapping_unmap(vaddr); - pagefault_enable(); - preempt_enable(); -} - +/* Temporary mappings which are only valid in the current context */ static inline void __iomem * io_mapping_map_local_wc(struct io_mapping *mapping, unsigned long offset) {