From patchwork Fri Jun 17 12:57:48 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 582948 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 52022C43334 for ; Fri, 17 Jun 2022 12:58:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1382405AbiFQM6S (ORCPT ); Fri, 17 Jun 2022 08:58:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46334 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1382226AbiFQM6L (ORCPT ); Fri, 17 Jun 2022 08:58:11 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1E5262B1AF; Fri, 17 Jun 2022 05:58:10 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id AD2F6B82682; Fri, 17 Jun 2022 12:58:08 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 593ABC3411F; Fri, 17 Jun 2022 12:58:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1655470687; bh=PHa+k1YPCB+2jgYk545vxPTI79A930ycNAnnkPIO8Q0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nLNheZIMb11YnK30s1ue4ClOfmXib4scSxsRBkan3jiCrsYF14v8dRzqdsbD07xD/ 7CVlJX/9vypOil3A0ym7H4qwTjHxFVs2953dx4vTr/1tKVrlExjRwnVrNjB56/54b8 mI5c0Afql8VfQwtkoOtgPCBjeHOOsjVos0BnP7RKevmdbYMVMVehSfmRtWEVM7Zo+0 32Oor1aZzOjFgybMMdE7DBEwLj2FGEfKPYV0Lcgg2w1dTdhpLzSWnnUROwn+W6xw1r brAoIaL/gkUAawWzU4UY6DLRjidv0/55hJJFNX7mCSRMsy9E0xCQG8rGi327Q83BHu JVJbuHA/NBGRA== From: Arnd Bergmann To: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Arnd Bergmann , Jakub Kicinski , Christoph Hellwig , Marek Szyprowski , Robin Murphy , iommu@lists.linux-foundation.org, Khalid Aziz , "Maciej W . Rozycki" , Matt Wang , Miquel van Smoorenburg , Mark Salyzyn , linuxppc-dev@lists.ozlabs.org, linux-arch@vger.kernel.org, linux-alpha@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-parisc@vger.kernel.org, Denis Efremov Subject: [PATCH v2 1/3] scsi: dpt_i2o: drop stale VIRT_TO_BUS dependency Date: Fri, 17 Jun 2022 14:57:48 +0200 Message-Id: <20220617125750.728590-2-arnd@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20220617125750.728590-1-arnd@kernel.org> References: <20220617125750.728590-1-arnd@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org From: Arnd Bergmann The dpt_i2o driver was fixed to stop using virt_to_bus() in 2008, but it still has a stale reference in an error handling code path that could never work. Fix it up to build without VIRT_TO_BUS and remove the Kconfig dependency. The alternative to this would be to just remove the driver, as it is clearly obsolete. The i2o driver layer was removed in 2015 with commit 4a72a7af462d ("staging: remove i2o subsystem"), but the even older dpt_i2o scsi driver stayed around. The last non-cleanup patches I could find were from Miquel van Smoorenburg and Mark Salyzyn back in 2008, they might know if there is any chance of the hardware still being used anywhere. Fixes: 67af2b060e02 ("[SCSI] dpt_i2o: move from virt_to_bus/bus_to_virt to dma_alloc_coherent") Cc: Miquel van Smoorenburg Cc: Mark Salyzyn Signed-off-by: Arnd Bergmann Reviewed-by: Hannes Reinecke --- drivers/scsi/Kconfig | 2 +- drivers/scsi/dpt_i2o.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig index a9fe5152addd..cf75588a2587 100644 --- a/drivers/scsi/Kconfig +++ b/drivers/scsi/Kconfig @@ -460,7 +460,7 @@ config SCSI_MVUMI config SCSI_DPT_I2O tristate "Adaptec I2O RAID support " - depends on SCSI && PCI && VIRT_TO_BUS + depends on SCSI && PCI help This driver supports all of Adaptec's I2O based RAID controllers as well as the DPT SmartRaid V cards. This is an Adaptec maintained diff --git a/drivers/scsi/dpt_i2o.c b/drivers/scsi/dpt_i2o.c index 2e9155ba7408..55dfe7011912 100644 --- a/drivers/scsi/dpt_i2o.c +++ b/drivers/scsi/dpt_i2o.c @@ -52,11 +52,11 @@ MODULE_DESCRIPTION("Adaptec I2O RAID Driver"); #include #include +#include #include #include #include /* for boot_cpu_data */ -#include /* for virt_to_bus, etc. */ #include #include @@ -2112,7 +2112,7 @@ static irqreturn_t adpt_isr(int irq, void *dev_id) } else { /* Ick, we should *never* be here */ printk(KERN_ERR "dpti: reply frame not from pool\n"); - reply = (u8 *)bus_to_virt(m); + goto out; } if (readl(reply) & MSG_FAIL) { From patchwork Fri Jun 17 12:57:49 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 582711 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 786FAC433EF for ; Fri, 17 Jun 2022 12:58:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1382478AbiFQM6p (ORCPT ); Fri, 17 Jun 2022 08:58:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46580 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1382325AbiFQM6R (ORCPT ); Fri, 17 Jun 2022 08:58:17 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 965CD4B872; Fri, 17 Jun 2022 05:58:12 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 3C6E961FCC; Fri, 17 Jun 2022 12:58:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B7C10C341C0; Fri, 17 Jun 2022 12:58:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1655470691; bh=rNm86lHtdCfu2hQjLvtPm7z28Z3EUdsosPvVob2uK6c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ygkdf/zmdk71Eb66/cIYABaIOydmHLb3jlIiJJptXcoAXufQUr7tMhsRsDheMPdqH e5ISxCjZXTcX2qiIvNdBEqXlzWuz8zHsn9AWHWWu8jPURpKbbjdmESq0vjmndUGCcy DQBV4ioVojLmkogSB/lPkKgwp8LeVczpRMkUlBmkhxN8O9sUoXeOf40ucejA3cNd35 900omwI5Kek+tndhSBesQTJZErc3Y3T5GS60URdgKDhTpbd5D1XhrVgrJDmhzSFxeN K9FpTujgf4rZlaLsXk5SKGKqVVgFUGo3uAZjKQsfVpjYpXBp+WF8b477RootiIo8D4 B7PEYAt29rg5g== From: Arnd Bergmann To: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Arnd Bergmann , Jakub Kicinski , Christoph Hellwig , Marek Szyprowski , Robin Murphy , iommu@lists.linux-foundation.org, Khalid Aziz , "Maciej W . Rozycki" , Matt Wang , Miquel van Smoorenburg , Mark Salyzyn , linuxppc-dev@lists.ozlabs.org, linux-arch@vger.kernel.org, linux-alpha@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-parisc@vger.kernel.org, Denis Efremov Subject: [PATCH v2 2/3] scsi: BusLogic remove bus_to_virt Date: Fri, 17 Jun 2022 14:57:49 +0200 Message-Id: <20220617125750.728590-3-arnd@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20220617125750.728590-1-arnd@kernel.org> References: <20220617125750.728590-1-arnd@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org From: Arnd Bergmann The BusLogic driver is the last remaining driver that relies on the deprecated bus_to_virt() function, which in turn only works on a few architectures, and is incompatible with both swiotlb and iommu support. Before commit 391e2f25601e ("[SCSI] BusLogic: Port driver to 64-bit."), the driver had a dependency on x86-32, presumably because of this problem. However, the change introduced another bug that made it still impossible to use the driver on any 64-bit machine. This was in turn fixed in commit 56f396146af2 ("scsi: BusLogic: Fix 64-bit system enumeration error for Buslogic"), 8 years later, which shows that there are not a lot of users. Maciej is still using the driver on 32-bit hardware, and Khalid mentioned that the driver works with the device emulation used in VirtualBox and VMware. Both of those only emulate it for Windows 2000 and older operating systems that did not ship with the better LSI logic driver. Do a minimum fix that searches through the list of descriptors to find one that matches the bus address. This is clearly as inefficient as was indicated in the code comment about the lack of a bus_to_virt() replacement. A better fix would likely involve changing out the entire descriptor allocation for a simpler one, but that would be much more invasive. Cc: Maciej W. Rozycki Cc: Matt Wang Cc: Khalid Aziz Signed-off-by: Arnd Bergmann Reviewed-by: Robin Murphy Reviewed-by: Hannes Reinecke --- drivers/scsi/BusLogic.c | 27 ++++++++++++++++----------- drivers/scsi/Kconfig | 2 +- 2 files changed, 17 insertions(+), 12 deletions(-) diff --git a/drivers/scsi/BusLogic.c b/drivers/scsi/BusLogic.c index a897c8f914cf..d057abfcdd5c 100644 --- a/drivers/scsi/BusLogic.c +++ b/drivers/scsi/BusLogic.c @@ -2515,12 +2515,26 @@ static int blogic_resultcode(struct blogic_adapter *adapter, return (hoststatus << 16) | tgt_status; } +/* + * turn the dma address from an inbox into a ccb pointer + * This is rather inefficient. + */ +static struct blogic_ccb * +blogic_inbox_to_ccb(struct blogic_adapter *adapter, struct blogic_inbox *inbox) +{ + struct blogic_ccb *ccb; + + for (ccb = adapter->all_ccbs; ccb; ccb = ccb->next_all) + if (inbox->ccb == ccb->dma_handle) + break; + + return ccb; +} /* blogic_scan_inbox scans the Incoming Mailboxes saving any Incoming Mailbox entries for completion processing. */ - static void blogic_scan_inbox(struct blogic_adapter *adapter) { /* @@ -2540,16 +2554,7 @@ static void blogic_scan_inbox(struct blogic_adapter *adapter) enum blogic_cmplt_code comp_code; while ((comp_code = next_inbox->comp_code) != BLOGIC_INBOX_FREE) { - /* - We are only allowed to do this because we limit our - architectures we run on to machines where bus_to_virt( - actually works. There *needs* to be a dma_addr_to_virt() - in the new PCI DMA mapping interface to replace - bus_to_virt() or else this code is going to become very - innefficient. - */ - struct blogic_ccb *ccb = - (struct blogic_ccb *) bus_to_virt(next_inbox->ccb); + struct blogic_ccb *ccb = blogic_inbox_to_ccb(adapter, adapter->next_inbox); if (comp_code != BLOGIC_CMD_NOTFOUND) { if (ccb->status == BLOGIC_CCB_ACTIVE || ccb->status == BLOGIC_CCB_RESET) { diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig index cf75588a2587..56bdc08d0b77 100644 --- a/drivers/scsi/Kconfig +++ b/drivers/scsi/Kconfig @@ -513,7 +513,7 @@ config SCSI_HPTIOP config SCSI_BUSLOGIC tristate "BusLogic SCSI support" - depends on PCI && SCSI && VIRT_TO_BUS + depends on PCI && SCSI help This is support for BusLogic MultiMaster and FlashPoint SCSI Host Adapters. Consult the SCSI-HOWTO, available from From patchwork Fri Jun 17 12:57:50 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 582947 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BA965C43334 for ; Fri, 17 Jun 2022 12:59:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1382483AbiFQM6q (ORCPT ); Fri, 17 Jun 2022 08:58:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46830 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1382418AbiFQM6Z (ORCPT ); Fri, 17 Jun 2022 08:58:25 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7EE5C2E084; Fri, 17 Jun 2022 05:58:17 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 35EE461FCC; Fri, 17 Jun 2022 12:58:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 23E9BC3411B; Fri, 17 Jun 2022 12:58:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1655470696; bh=q6ahBsNODq++hnrTnzK6LlJOq33Neo0r38bziwQcZbw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UPmZ5BYtt0vbAbAXt6ya5plQRjChvgSM1c7v32PlkHWDhZDq1REQ6q5N+fc1iEzSu vqseKn5X4boZHVHwVZPF8SFi4I85YGy1ywm9jj8zNmAkSblvYtEIuHTcMr+W4oHjHi 4oAUOWbX6H5L37llZ5+sPpn8XfUm2j2ZzqiT0zdLRSqX9Vl7/i4sbxwwxzYW0fAdT+ t63UHa0fU+I+6IOnIev9JF/FtHIoVLwrmKIB5T5LqPL6E7dY/Nt6FVphG5fTcZ6nXi hu3jIDlj+yjToY1Jwafa7pqWAvBPkLWoibcjRh9fRBsqP9f4d+MTrxXnfJo/B/Sefj 2f6lkwETcLXlA== From: Arnd Bergmann To: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Arnd Bergmann , Jakub Kicinski , Christoph Hellwig , Marek Szyprowski , Robin Murphy , iommu@lists.linux-foundation.org, Khalid Aziz , "Maciej W . Rozycki" , Matt Wang , Miquel van Smoorenburg , Mark Salyzyn , linuxppc-dev@lists.ozlabs.org, linux-arch@vger.kernel.org, linux-alpha@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-parisc@vger.kernel.org, Denis Efremov , Geert Uytterhoeven , Michael Ellerman Subject: [PATCH v2 3/3] arch/*/: remove CONFIG_VIRT_TO_BUS Date: Fri, 17 Jun 2022 14:57:50 +0200 Message-Id: <20220617125750.728590-4-arnd@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20220617125750.728590-1-arnd@kernel.org> References: <20220617125750.728590-1-arnd@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org From: Arnd Bergmann All architecture-independent users of virt_to_bus() and bus_to_virt() have been fixed to use the dma mapping interfaces or have been removed now. This means the definitions on most architectures, and the CONFIG_VIRT_TO_BUS symbol are now obsolete and can be removed. The only exceptions to this are a few network and scsi drivers for m68k Amiga and VME machines and ppc32 Macintosh. These drivers work correctly with the old interfaces and are probably not worth changing. On alpha and parisc, virt_to_bus() were still used in asm/floppy.h. alpha can use isa_virt_to_bus() like x86 does, and parisc can just open-code the virt_to_phys() here, as this is architecture specific code. I tried updating the bus-virt-phys-mapping.rst documentation, which started as an email from Linus to explain some details of the Linux-2.0 driver interfaces. The bits about virt_to_bus() were declared obsolete backin 2000, and the rest is not all that relevant any more, so in the end I just decided to remove the file completely. Reviewed-by: Geert Uytterhoeven Acked-by: Geert Uytterhoeven Acked-by: Michael Ellerman (powerpc) Signed-off-by: Arnd Bergmann --- .../core-api/bus-virt-phys-mapping.rst | 220 ------------------ Documentation/core-api/dma-api-howto.rst | 14 -- Documentation/core-api/index.rst | 1 - .../translations/zh_CN/core-api/index.rst | 1 - arch/alpha/Kconfig | 1 - arch/alpha/include/asm/floppy.h | 2 +- arch/alpha/include/asm/io.h | 8 +- arch/ia64/Kconfig | 1 - arch/ia64/include/asm/io.h | 8 - arch/m68k/Kconfig | 1 - arch/m68k/include/asm/virtconvert.h | 4 +- arch/microblaze/Kconfig | 1 - arch/microblaze/include/asm/io.h | 2 - arch/mips/Kconfig | 1 - arch/mips/include/asm/io.h | 9 - arch/parisc/Kconfig | 1 - arch/parisc/include/asm/floppy.h | 4 +- arch/parisc/include/asm/io.h | 2 - arch/powerpc/Kconfig | 1 - arch/powerpc/include/asm/io.h | 2 - arch/riscv/include/asm/page.h | 1 - arch/x86/Kconfig | 1 - arch/x86/include/asm/io.h | 9 - arch/xtensa/Kconfig | 1 - arch/xtensa/include/asm/io.h | 3 - include/asm-generic/io.h | 14 -- mm/Kconfig | 8 - 27 files changed, 10 insertions(+), 311 deletions(-) delete mode 100644 Documentation/core-api/bus-virt-phys-mapping.rst diff --git a/Documentation/core-api/bus-virt-phys-mapping.rst b/Documentation/core-api/bus-virt-phys-mapping.rst deleted file mode 100644 index c72b24a7d52c..000000000000 --- a/Documentation/core-api/bus-virt-phys-mapping.rst +++ /dev/null @@ -1,220 +0,0 @@ -========================================================== -How to access I/O mapped memory from within device drivers -========================================================== - -:Author: Linus - -.. warning:: - - The virt_to_bus() and bus_to_virt() functions have been - superseded by the functionality provided by the PCI DMA interface - (see Documentation/core-api/dma-api-howto.rst). They continue - to be documented below for historical purposes, but new code - must not use them. --davidm 00/12/12 - -:: - - [ This is a mail message in response to a query on IO mapping, thus the - strange format for a "document" ] - -The AHA-1542 is a bus-master device, and your patch makes the driver give the -controller the physical address of the buffers, which is correct on x86 -(because all bus master devices see the physical memory mappings directly). - -However, on many setups, there are actually **three** different ways of looking -at memory addresses, and in this case we actually want the third, the -so-called "bus address". - -Essentially, the three ways of addressing memory are (this is "real memory", -that is, normal RAM--see later about other details): - - - CPU untranslated. This is the "physical" address. Physical address - 0 is what the CPU sees when it drives zeroes on the memory bus. - - - CPU translated address. This is the "virtual" address, and is - completely internal to the CPU itself with the CPU doing the appropriate - translations into "CPU untranslated". - - - bus address. This is the address of memory as seen by OTHER devices, - not the CPU. Now, in theory there could be many different bus - addresses, with each device seeing memory in some device-specific way, but - happily most hardware designers aren't actually actively trying to make - things any more complex than necessary, so you can assume that all - external hardware sees the memory the same way. - -Now, on normal PCs the bus address is exactly the same as the physical -address, and things are very simple indeed. However, they are that simple -because the memory and the devices share the same address space, and that is -not generally necessarily true on other PCI/ISA setups. - -Now, just as an example, on the PReP (PowerPC Reference Platform), the -CPU sees a memory map something like this (this is from memory):: - - 0-2 GB "real memory" - 2 GB-3 GB "system IO" (inb/out and similar accesses on x86) - 3 GB-4 GB "IO memory" (shared memory over the IO bus) - -Now, that looks simple enough. However, when you look at the same thing from -the viewpoint of the devices, you have the reverse, and the physical memory -address 0 actually shows up as address 2 GB for any IO master. - -So when the CPU wants any bus master to write to physical memory 0, it -has to give the master address 0x80000000 as the memory address. - -So, for example, depending on how the kernel is actually mapped on the -PPC, you can end up with a setup like this:: - - physical address: 0 - virtual address: 0xC0000000 - bus address: 0x80000000 - -where all the addresses actually point to the same thing. It's just seen -through different translations.. - -Similarly, on the Alpha, the normal translation is:: - - physical address: 0 - virtual address: 0xfffffc0000000000 - bus address: 0x40000000 - -(but there are also Alphas where the physical address and the bus address -are the same). - -Anyway, the way to look up all these translations, you do:: - - #include - - phys_addr = virt_to_phys(virt_addr); - virt_addr = phys_to_virt(phys_addr); - bus_addr = virt_to_bus(virt_addr); - virt_addr = bus_to_virt(bus_addr); - -Now, when do you need these? - -You want the **virtual** address when you are actually going to access that -pointer from the kernel. So you can have something like this:: - - /* - * this is the hardware "mailbox" we use to communicate with - * the controller. The controller sees this directly. - */ - struct mailbox { - __u32 status; - __u32 bufstart; - __u32 buflen; - .. - } mbox; - - unsigned char * retbuffer; - - /* get the address from the controller */ - retbuffer = bus_to_virt(mbox.bufstart); - switch (retbuffer[0]) { - case STATUS_OK: - ... - -on the other hand, you want the bus address when you have a buffer that -you want to give to the controller:: - - /* ask the controller to read the sense status into "sense_buffer" */ - mbox.bufstart = virt_to_bus(&sense_buffer); - mbox.buflen = sizeof(sense_buffer); - mbox.status = 0; - notify_controller(&mbox); - -And you generally **never** want to use the physical address, because you can't -use that from the CPU (the CPU only uses translated virtual addresses), and -you can't use it from the bus master. - -So why do we care about the physical address at all? We do need the physical -address in some cases, it's just not very often in normal code. The physical -address is needed if you use memory mappings, for example, because the -"remap_pfn_range()" mm function wants the physical address of the memory to -be remapped as measured in units of pages, a.k.a. the pfn (the memory -management layer doesn't know about devices outside the CPU, so it -shouldn't need to know about "bus addresses" etc). - -.. note:: - - The above is only one part of the whole equation. The above - only talks about "real memory", that is, CPU memory (RAM). - -There is a completely different type of memory too, and that's the "shared -memory" on the PCI or ISA bus. That's generally not RAM (although in the case -of a video graphics card it can be normal DRAM that is just used for a frame -buffer), but can be things like a packet buffer in a network card etc. - -This memory is called "PCI memory" or "shared memory" or "IO memory" or -whatever, and there is only one way to access it: the readb/writeb and -related functions. You should never take the address of such memory, because -there is really nothing you can do with such an address: it's not -conceptually in the same memory space as "real memory" at all, so you cannot -just dereference a pointer. (Sadly, on x86 it **is** in the same memory space, -so on x86 it actually works to just deference a pointer, but it's not -portable). - -For such memory, you can do things like: - - - reading:: - - /* - * read first 32 bits from ISA memory at 0xC0000, aka - * C000:0000 in DOS terms - */ - unsigned int signature = isa_readl(0xC0000); - - - remapping and writing:: - - /* - * remap framebuffer PCI memory area at 0xFC000000, - * size 1MB, so that we can access it: We can directly - * access only the 640k-1MB area, so anything else - * has to be remapped. - */ - void __iomem *baseptr = ioremap(0xFC000000, 1024*1024); - - /* write a 'A' to the offset 10 of the area */ - writeb('A',baseptr+10); - - /* unmap when we unload the driver */ - iounmap(baseptr); - - - copying and clearing:: - - /* get the 6-byte Ethernet address at ISA address E000:0040 */ - memcpy_fromio(kernel_buffer, 0xE0040, 6); - /* write a packet to the driver */ - memcpy_toio(0xE1000, skb->data, skb->len); - /* clear the frame buffer */ - memset_io(0xA0000, 0, 0x10000); - -OK, that just about covers the basics of accessing IO portably. Questions? -Comments? You may think that all the above is overly complex, but one day you -might find yourself with a 500 MHz Alpha in front of you, and then you'll be -happy that your driver works ;) - -Note that kernel versions 2.0.x (and earlier) mistakenly called the -ioremap() function "vremap()". ioremap() is the proper name, but I -didn't think straight when I wrote it originally. People who have to -support both can do something like:: - - /* support old naming silliness */ - #if LINUX_VERSION_CODE < 0x020100 - #define ioremap vremap - #define iounmap vfree - #endif - -at the top of their source files, and then they can use the right names -even on 2.0.x systems. - -And the above sounds worse than it really is. Most real drivers really -don't do all that complex things (or rather: the complexity is not so -much in the actual IO accesses as in error handling and timeouts etc). -It's generally not hard to fix drivers, and in many cases the code -actually looks better afterwards:: - - unsigned long signature = *(unsigned int *) 0xC0000; - vs - unsigned long signature = readl(0xC0000); - -I think the second version actually is more readable, no? diff --git a/Documentation/core-api/dma-api-howto.rst b/Documentation/core-api/dma-api-howto.rst index 358d495456d1..828846804e25 100644 --- a/Documentation/core-api/dma-api-howto.rst +++ b/Documentation/core-api/dma-api-howto.rst @@ -707,20 +707,6 @@ to use the dma_sync_*() interfaces:: } } -Drivers converted fully to this interface should not use virt_to_bus() any -longer, nor should they use bus_to_virt(). Some drivers have to be changed a -little bit, because there is no longer an equivalent to bus_to_virt() in the -dynamic DMA mapping scheme - you have to always store the DMA addresses -returned by the dma_alloc_coherent(), dma_pool_alloc(), and dma_map_single() -calls (dma_map_sg() stores them in the scatterlist itself if the platform -supports dynamic DMA mapping in hardware) in your driver structures and/or -in the card registers. - -All drivers should be using these interfaces with no exceptions. It -is planned to completely remove virt_to_bus() and bus_to_virt() as -they are entirely deprecated. Some ports already do not provide these -as it is impossible to correctly support them. - Handling Errors =============== diff --git a/Documentation/core-api/index.rst b/Documentation/core-api/index.rst index 9ef37e985a40..0550282cfd6f 100644 --- a/Documentation/core-api/index.rst +++ b/Documentation/core-api/index.rst @@ -42,7 +42,6 @@ Library functionality that is used throughout the kernel. rbtree generic-radix-tree packing - bus-virt-phys-mapping this_cpu_ops timekeeping errseq diff --git a/Documentation/translations/zh_CN/core-api/index.rst b/Documentation/translations/zh_CN/core-api/index.rst index 26d9913fc8b6..c52175fc1b61 100644 --- a/Documentation/translations/zh_CN/core-api/index.rst +++ b/Documentation/translations/zh_CN/core-api/index.rst @@ -52,7 +52,6 @@ Todolist: circular-buffers generic-radix-tree packing - bus-virt-phys-mapping this_cpu_ops timekeeping errseq diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig index 7d0d26b5b3f5..97fce7386b00 100644 --- a/arch/alpha/Kconfig +++ b/arch/alpha/Kconfig @@ -17,7 +17,6 @@ config ALPHA select HAVE_PERF_EVENTS select NEED_DMA_MAP_STATE select NEED_SG_DMA_LENGTH - select VIRT_TO_BUS select GENERIC_IRQ_PROBE select GENERIC_PCI_IOMAP select AUTO_IRQ_AFFINITY if SMP diff --git a/arch/alpha/include/asm/floppy.h b/arch/alpha/include/asm/floppy.h index 588758685439..64b42d9591fc 100644 --- a/arch/alpha/include/asm/floppy.h +++ b/arch/alpha/include/asm/floppy.h @@ -20,7 +20,7 @@ #define fd_free_dma() free_dma(FLOPPY_DMA) #define fd_clear_dma_ff() clear_dma_ff(FLOPPY_DMA) #define fd_set_dma_mode(mode) set_dma_mode(FLOPPY_DMA,mode) -#define fd_set_dma_addr(addr) set_dma_addr(FLOPPY_DMA,virt_to_bus(addr)) +#define fd_set_dma_addr(addr) set_dma_addr(FLOPPY_DMA,isa_virt_to_bus(addr)) #define fd_set_dma_count(count) set_dma_count(FLOPPY_DMA,count) #define fd_enable_irq() enable_irq(FLOPPY_IRQ) #define fd_disable_irq() disable_irq(FLOPPY_IRQ) diff --git a/arch/alpha/include/asm/io.h b/arch/alpha/include/asm/io.h index c9cb554fbe54..d277189b2677 100644 --- a/arch/alpha/include/asm/io.h +++ b/arch/alpha/include/asm/io.h @@ -106,15 +106,15 @@ static inline void * phys_to_virt(unsigned long address) extern unsigned long __direct_map_base; extern unsigned long __direct_map_size; -static inline unsigned long __deprecated virt_to_bus(volatile void *address) +static inline unsigned long __deprecated isa_virt_to_bus(volatile void *address) { unsigned long phys = virt_to_phys(address); unsigned long bus = phys + __direct_map_base; return phys <= __direct_map_size ? bus : 0; } -#define isa_virt_to_bus virt_to_bus +#define isa_virt_to_bus isa_virt_to_bus -static inline void * __deprecated bus_to_virt(unsigned long address) +static inline void * __deprecated isa_bus_to_virt(unsigned long address) { void *virt; @@ -125,7 +125,7 @@ static inline void * __deprecated bus_to_virt(unsigned long address) virt = phys_to_virt(address); return (long)address <= 0 ? NULL : virt; } -#define isa_bus_to_virt bus_to_virt +#define isa_bus_to_virt isa_bus_to_virt /* * There are different chipsets to interface the Alpha CPUs to the world. diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig index cb93769a9f2a..26ac8ea15a9e 100644 --- a/arch/ia64/Kconfig +++ b/arch/ia64/Kconfig @@ -39,7 +39,6 @@ config IA64 select HAVE_FUNCTION_DESCRIPTORS select HAVE_VIRT_CPU_ACCOUNTING select HUGETLB_PAGE_SIZE_VARIABLE if HUGETLB_PAGE - select VIRT_TO_BUS select GENERIC_IRQ_PROBE select GENERIC_PENDING_IRQ if SMP select GENERIC_IRQ_SHOW diff --git a/arch/ia64/include/asm/io.h b/arch/ia64/include/asm/io.h index 6d93b923b379..ce66dfc0e719 100644 --- a/arch/ia64/include/asm/io.h +++ b/arch/ia64/include/asm/io.h @@ -96,14 +96,6 @@ extern u64 kern_mem_attribute (unsigned long phys_addr, unsigned long size); extern int valid_phys_addr_range (phys_addr_t addr, size_t count); /* efi.c */ extern int valid_mmap_phys_addr_range (unsigned long pfn, size_t count); -/* - * The following two macros are deprecated and scheduled for removal. - * Please use the PCI-DMA interface defined in instead. - */ -#define bus_to_virt phys_to_virt -#define virt_to_bus virt_to_phys -#define page_to_bus page_to_phys - # endif /* KERNEL */ /* diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig index 936cce42ae9a..b06faf6c0b27 100644 --- a/arch/m68k/Kconfig +++ b/arch/m68k/Kconfig @@ -30,7 +30,6 @@ config M68K select OLD_SIGACTION select OLD_SIGSUSPEND3 select UACCESS_MEMCPY if !MMU - select VIRT_TO_BUS select ZONE_DMA config CPU_BIG_ENDIAN diff --git a/arch/m68k/include/asm/virtconvert.h b/arch/m68k/include/asm/virtconvert.h index ca91b32dc6ef..0a27905b0036 100644 --- a/arch/m68k/include/asm/virtconvert.h +++ b/arch/m68k/include/asm/virtconvert.h @@ -33,9 +33,11 @@ static inline void *phys_to_virt(unsigned long address) /* * IO bus memory addresses are 1:1 with the physical address, + * deprecated globally but still used on two machines. */ +#if defined(CONFIG_AMIGA) || defined(CONFIG_VME) #define virt_to_bus virt_to_phys -#define bus_to_virt phys_to_virt +#endif #endif #endif diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig index 8cf429ad1c84..415182eeb082 100644 --- a/arch/microblaze/Kconfig +++ b/arch/microblaze/Kconfig @@ -38,7 +38,6 @@ config MICROBLAZE select OF_EARLY_FLATTREE select PCI_DOMAINS_GENERIC if PCI select PCI_SYSCALL if PCI - select VIRT_TO_BUS select CPU_NO_EFFICIENT_FFS select MMU_GATHER_NO_RANGE select SPARSE_IRQ diff --git a/arch/microblaze/include/asm/io.h b/arch/microblaze/include/asm/io.h index b6a57f8468f0..c1d78b8977a6 100644 --- a/arch/microblaze/include/asm/io.h +++ b/arch/microblaze/include/asm/io.h @@ -30,8 +30,6 @@ extern resource_size_t isa_mem_base; #define PCI_IOBASE ((void __iomem *)_IO_BASE) #define IO_SPACE_LIMIT (0xFFFFFFFF) -#define page_to_bus(page) (page_to_phys(page)) - extern void iounmap(volatile void __iomem *addr); extern void __iomem *ioremap(phys_addr_t address, unsigned long size); diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 9457894db237..69f3b9b4677b 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -100,7 +100,6 @@ config MIPS select RTC_LIB select SYSCTL_EXCEPTION_TRACE select TRACE_IRQFLAGS_SUPPORT - select VIRT_TO_BUS select ARCH_HAS_ELFCORE_COMPAT select HAVE_ARCH_KCSAN if 64BIT diff --git a/arch/mips/include/asm/io.h b/arch/mips/include/asm/io.h index 6f5c86d2bab4..cd9168f34fb7 100644 --- a/arch/mips/include/asm/io.h +++ b/arch/mips/include/asm/io.h @@ -147,15 +147,6 @@ static inline void *isa_bus_to_virt(unsigned long address) return phys_to_virt(address); } -/* - * However PCI ones are not necessarily 1:1 and therefore these interfaces - * are forbidden in portable PCI drivers. - * - * Allow them for x86 for legacy drivers, though. - */ -#define virt_to_bus virt_to_phys -#define bus_to_virt phys_to_virt - /* * Change "struct page" to physical address. */ diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig index 5f2448dc5a2b..b0d68e9e2df0 100644 --- a/arch/parisc/Kconfig +++ b/arch/parisc/Kconfig @@ -43,7 +43,6 @@ config PARISC select SYSCTL_ARCH_UNALIGN_ALLOW select SYSCTL_EXCEPTION_TRACE select HAVE_MOD_ARCH_SPECIFIC - select VIRT_TO_BUS select MODULES_USE_ELF_RELA select CLONE_BACKWARDS select TTY # Needed for pdc_cons.c diff --git a/arch/parisc/include/asm/floppy.h b/arch/parisc/include/asm/floppy.h index 762cfe7778c0..b318a7df52f6 100644 --- a/arch/parisc/include/asm/floppy.h +++ b/arch/parisc/include/asm/floppy.h @@ -179,7 +179,7 @@ static void _fd_chose_dma_mode(char *addr, unsigned long size) { if(can_use_virtual_dma == 2) { if((unsigned int) addr >= (unsigned int) high_memory || - virt_to_bus(addr) >= 0x1000000 || + virt_to_phys(addr) >= 0x1000000 || _CROSS_64KB(addr, size, 0)) use_virtual_dma = 1; else @@ -215,7 +215,7 @@ static int hard_dma_setup(char *addr, unsigned long size, int mode, int io) doing_pdma = 0; clear_dma_ff(FLOPPY_DMA); set_dma_mode(FLOPPY_DMA,mode); - set_dma_addr(FLOPPY_DMA,virt_to_bus(addr)); + set_dma_addr(FLOPPY_DMA,virt_to_phys(addr)); set_dma_count(FLOPPY_DMA,size); enable_dma(FLOPPY_DMA); return 0; diff --git a/arch/parisc/include/asm/io.h b/arch/parisc/include/asm/io.h index 837ddddbac6a..42ffb60a6ea9 100644 --- a/arch/parisc/include/asm/io.h +++ b/arch/parisc/include/asm/io.h @@ -7,8 +7,6 @@ #define virt_to_phys(a) ((unsigned long)__pa(a)) #define phys_to_virt(a) __va(a) -#define virt_to_bus virt_to_phys -#define bus_to_virt phys_to_virt static inline unsigned long isa_bus_to_virt(unsigned long addr) { BUG(); diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 8f76499919fe..66418dfeb771 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -277,7 +277,6 @@ config PPC select SYSCTL_EXCEPTION_TRACE select THREAD_INFO_IN_TASK select TRACE_IRQFLAGS_SUPPORT - select VIRT_TO_BUS if !PPC64 # # Please keep this list sorted alphabetically. # diff --git a/arch/powerpc/include/asm/io.h b/arch/powerpc/include/asm/io.h index c5a5f7c9b231..73fcd5cdb662 100644 --- a/arch/powerpc/include/asm/io.h +++ b/arch/powerpc/include/asm/io.h @@ -985,8 +985,6 @@ static inline void * bus_to_virt(unsigned long address) } #define bus_to_virt bus_to_virt -#define page_to_bus(page) (page_to_phys(page) + PCI_DRAM_OFFSET) - #endif /* CONFIG_PPC32 */ /* access ports */ diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h index 1526e410e802..ac70b0fd9a9a 100644 --- a/arch/riscv/include/asm/page.h +++ b/arch/riscv/include/asm/page.h @@ -167,7 +167,6 @@ extern phys_addr_t __phys_addr_symbol(unsigned long x); #define page_to_virt(page) (pfn_to_virt(page_to_pfn(page))) #define page_to_phys(page) (pfn_to_phys(page_to_pfn(page))) -#define page_to_bus(page) (page_to_phys(page)) #define phys_to_page(paddr) (pfn_to_page(phys_to_pfn(paddr))) #define sym_to_pfn(x) __phys_to_pfn(__pa_symbol(x)) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index abe751626a35..9c50d53fa6e7 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -279,7 +279,6 @@ config X86 select THREAD_INFO_IN_TASK select TRACE_IRQFLAGS_SUPPORT select USER_STACKTRACE_SUPPORT - select VIRT_TO_BUS select HAVE_ARCH_KCSAN if X86_64 select X86_FEATURE_NAMES if PROC_FS select PROC_PID_ARCH_STATUS if PROC_FS diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h index 1870b99c3356..e9025640f634 100644 --- a/arch/x86/include/asm/io.h +++ b/arch/x86/include/asm/io.h @@ -169,15 +169,6 @@ static inline unsigned int isa_virt_to_bus(volatile void *address) } #define isa_bus_to_virt phys_to_virt -/* - * However PCI ones are not necessarily 1:1 and therefore these interfaces - * are forbidden in portable PCI drivers. - * - * Allow them on x86 for legacy drivers, though. - */ -#define virt_to_bus virt_to_phys -#define bus_to_virt phys_to_virt - /* * The default ioremap() behavior is non-cached; if you need something * else, you probably want one of the following. diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig index 0b0f0172cced..92a24ed738a5 100644 --- a/arch/xtensa/Kconfig +++ b/arch/xtensa/Kconfig @@ -50,7 +50,6 @@ config XTENSA select MODULES_USE_ELF_RELA select PERF_USE_VMALLOC select TRACE_IRQFLAGS_SUPPORT - select VIRT_TO_BUS help Xtensa processors are 32-bit RISC machines designed by Tensilica primarily for embedded systems. These processors are both diff --git a/arch/xtensa/include/asm/io.h b/arch/xtensa/include/asm/io.h index 54188e69b988..a5b707e1c0f4 100644 --- a/arch/xtensa/include/asm/io.h +++ b/arch/xtensa/include/asm/io.h @@ -63,9 +63,6 @@ static inline void iounmap(volatile void __iomem *addr) xtensa_iounmap(addr); } -#define virt_to_bus virt_to_phys -#define bus_to_virt phys_to_virt - #endif /* CONFIG_MMU */ #include diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h index 7ce93aaf69f8..f57015eaed73 100644 --- a/include/asm-generic/io.h +++ b/include/asm-generic/io.h @@ -1059,20 +1059,6 @@ static inline void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr) } #endif -#ifdef CONFIG_VIRT_TO_BUS -#ifndef virt_to_bus -static inline unsigned long virt_to_bus(void *address) -{ - return (unsigned long)address; -} - -static inline void *bus_to_virt(unsigned long address) -{ - return (void *)address; -} -#endif -#endif - #ifndef memset_io #define memset_io memset_io /** diff --git a/mm/Kconfig b/mm/Kconfig index 169e64192e48..b7a44b17c79f 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -639,14 +639,6 @@ config BOUNCE memory available to the CPU. Enabled by default when HIGHMEM is selected, but you may say n to override this. -config VIRT_TO_BUS - bool - help - An architecture should select this if it implements the - deprecated interface virt_to_bus(). All new architectures - should probably not select this. - - config MMU_NOTIFIER bool select SRCU