From patchwork Fri Jul 15 15:36:17 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 12919402 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 552E6C43334 for ; Fri, 15 Jul 2022 15:36:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234928AbiGOPgr (ORCPT ); Fri, 15 Jul 2022 11:36:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40474 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235010AbiGOPgn (ORCPT ); Fri, 15 Jul 2022 11:36:43 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 96EEB5A2D1 for ; Fri, 15 Jul 2022 08:36:42 -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 17242B82D11 for ; Fri, 15 Jul 2022 15:36:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 52F0BC3411E; Fri, 15 Jul 2022 15:36:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1657899399; bh=2dlhaiT/PHyRwDrAtnA08dgWECmHLItKNahH8WkarKE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=h4trP2ob4A2ErmThvl4gd1T45jmNOHpJkkmZ1awCz0oVwyj3JrvX4aII3IAojU2cY KAL8JO4lD+5wrEwZermgbP2S6YQntn1mltQMgzIsNlxZCIOJXSSMZy41QDCWvhoDin WTJLS8uD2tqzjUjc81LhSAPt+6xIZ+FVx1QtG+itb+vj9LiJDiNlOnIMDp9YHYY+IP 8hYbSXLqvxjc4bjlzYzlS84ICY7j+AKCltICffaAqHt47At18N6HHVY1jMkg+siLay YtRjbWZ4ccJ+VXGhP3pkiFebBRkZtEvZi0UCdnOeOYBuKMZsws2SZSYVWV4auPNq4U ZkfDrh/37CVxg== From: Arnd Bergmann To: linux-pci@vger.kernel.org Cc: Bjorn Helgaas , Arnd Bergmann , David Woodhouse , "David S . Miller" , Stafford Horne Subject: [PATCH 2/2] [RFC] sparc: Use generic pci_mmap_resource_range() Date: Fri, 15 Jul 2022 17:36:17 +0200 Message-Id: <20220715153617.3393420-2-arnd@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20220715153617.3393420-1-arnd@kernel.org> References: <20220715153617.3393420-1-arnd@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: Arnd Bergmann The main feature of the sparc specific implementation of pci_mmap_resource_range() is that it allows mapping the entire PCI I/O space for a PCI host bridge using the /proc/bus/pci interface on a bridge device. The generic implementation cannot do this, but it also appears that this got broken for sparc by commit 9eff02e2042f ("PCI: check mmap range of /proc/bus/pci files too"), which enforces that each address is part of a BAR for kernels after 2.6.28. Remove it all, assuming that the corresponding user space code has already been changed to access /dev/ioport instead a long time ago. The pci_iobar_pfn() function needs to be added to make it possible to map I/O resources. This is adapted from the powerpc version. Link: https://lore.kernel.org/lkml/1519887203.622.3.camel@infradead.org/t/ Signed-off-by: Arnd Bergmann --- It's quite possible that I missed something important, but it appears that David Miller was thinking of the pre-2.6.28 behavior that was already broken when David Woodhouse sent his series. --- arch/sparc/include/asm/pci.h | 1 + arch/sparc/kernel/pci.c | 154 +---------------------------------- 2 files changed, 5 insertions(+), 150 deletions(-) diff --git a/arch/sparc/include/asm/pci.h b/arch/sparc/include/asm/pci.h index 4deddf430e5d..dff90dce6cb7 100644 --- a/arch/sparc/include/asm/pci.h +++ b/arch/sparc/include/asm/pci.h @@ -37,6 +37,7 @@ static inline int pci_proc_domain(struct pci_bus *bus) #define HAVE_PCI_MMAP #define arch_can_pci_mmap_io() 1 #define HAVE_ARCH_PCI_GET_UNMAPPED_AREA +#define ARCH_GENERIC_PCI_MMAP_RESOURCE #define get_pci_unmapped_area get_fb_unmapped_area #endif /* CONFIG_SPARC64 */ diff --git a/arch/sparc/kernel/pci.c b/arch/sparc/kernel/pci.c index f580db840bf7..cb1ef25116e9 100644 --- a/arch/sparc/kernel/pci.c +++ b/arch/sparc/kernel/pci.c @@ -751,161 +751,15 @@ int pcibios_enable_device(struct pci_dev *dev, int mask) } /* Platform support for /proc/bus/pci/X/Y mmap()s. */ - -/* If the user uses a host-bridge as the PCI device, he may use - * this to perform a raw mmap() of the I/O or MEM space behind - * that controller. - * - * This can be useful for execution of x86 PCI bios initialization code - * on a PCI card, like the xfree86 int10 stuff does. - */ -static int __pci_mmap_make_offset_bus(struct pci_dev *pdev, struct vm_area_struct *vma, - enum pci_mmap_state mmap_state) +int pci_iobar_pfn(struct pci_dev *pdev, int bar, struct vm_area_struct *vma) { struct pci_pbm_info *pbm = pdev->dev.archdata.host_controller; - unsigned long space_size, user_offset, user_size; - - if (mmap_state == pci_mmap_io) { - space_size = resource_size(&pbm->io_space); - } else { - space_size = resource_size(&pbm->mem_space); - } - - /* Make sure the request is in range. */ - user_offset = vma->vm_pgoff << PAGE_SHIFT; - user_size = vma->vm_end - vma->vm_start; + resource_size_t ioaddr = pci_resource_start(pdev, bar); - if (user_offset >= space_size || - (user_offset + user_size) > space_size) + if (!pbm) return -EINVAL; - if (mmap_state == pci_mmap_io) { - vma->vm_pgoff = (pbm->io_space.start + - user_offset) >> PAGE_SHIFT; - } else { - vma->vm_pgoff = (pbm->mem_space.start + - user_offset) >> PAGE_SHIFT; - } - - return 0; -} - -/* Adjust vm_pgoff of VMA such that it is the physical page offset - * corresponding to the 32-bit pci bus offset for DEV requested by the user. - * - * Basically, the user finds the base address for his device which he wishes - * to mmap. They read the 32-bit value from the config space base register, - * add whatever PAGE_SIZE multiple offset they wish, and feed this into the - * offset parameter of mmap on /proc/bus/pci/XXX for that device. - * - * Returns negative error code on failure, zero on success. - */ -static int __pci_mmap_make_offset(struct pci_dev *pdev, - struct vm_area_struct *vma, - enum pci_mmap_state mmap_state) -{ - unsigned long user_paddr, user_size; - int i, err; - - /* First compute the physical address in vma->vm_pgoff, - * making sure the user offset is within range in the - * appropriate PCI space. - */ - err = __pci_mmap_make_offset_bus(pdev, vma, mmap_state); - if (err) - return err; - - /* If this is a mapping on a host bridge, any address - * is OK. - */ - if ((pdev->class >> 8) == PCI_CLASS_BRIDGE_HOST) - return err; - - /* Otherwise make sure it's in the range for one of the - * device's resources. - */ - user_paddr = vma->vm_pgoff << PAGE_SHIFT; - user_size = vma->vm_end - vma->vm_start; - - for (i = 0; i <= PCI_ROM_RESOURCE; i++) { - struct resource *rp = &pdev->resource[i]; - resource_size_t aligned_end; - - /* Active? */ - if (!rp->flags) - continue; - - /* Same type? */ - if (i == PCI_ROM_RESOURCE) { - if (mmap_state != pci_mmap_mem) - continue; - } else { - if ((mmap_state == pci_mmap_io && - (rp->flags & IORESOURCE_IO) == 0) || - (mmap_state == pci_mmap_mem && - (rp->flags & IORESOURCE_MEM) == 0)) - continue; - } - - /* Align the resource end to the next page address. - * PAGE_SIZE intentionally added instead of (PAGE_SIZE - 1), - * because actually we need the address of the next byte - * after rp->end. - */ - aligned_end = (rp->end + PAGE_SIZE) & PAGE_MASK; - - if ((rp->start <= user_paddr) && - (user_paddr + user_size) <= aligned_end) - break; - } - - if (i > PCI_ROM_RESOURCE) - return -EINVAL; - - return 0; -} - -/* Set vm_page_prot of VMA, as appropriate for this architecture, for a pci - * device mapping. - */ -static void __pci_mmap_set_pgprot(struct pci_dev *dev, struct vm_area_struct *vma, - enum pci_mmap_state mmap_state) -{ - /* Our io_remap_pfn_range takes care of this, do nothing. */ -} - -/* Perform the actual remap of the pages for a PCI device mapping, as appropriate - * for this architecture. The region in the process to map is described by vm_start - * and vm_end members of VMA, the BAR relative address is found in vm_pgoff. - * The pci device structure is provided so that architectures may make mapping - * decisions on a per-device or per-bus basis. - * - * Returns a negative error code on failure, zero on success. - */ -int pci_mmap_resource_range(struct pci_dev *dev, int bar, - struct vm_area_struct *vma, - enum pci_mmap_state mmap_state, int write_combine) -{ - int ret; - resource_size_t start, end; - - /* convert per-BAR address to PCI bus address */ - pci_resource_to_user(dev, bar, &dev->resource[bar], &start, &end); - vma->vm_pgoff += start >> PAGE_SHIFT; - - ret = __pci_mmap_make_offset(dev, vma, mmap_state); - if (ret < 0) - return ret; - - __pci_mmap_set_pgprot(dev, vma, mmap_state); - - vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); - ret = io_remap_pfn_range(vma, vma->vm_start, - vma->vm_pgoff, - vma->vm_end - vma->vm_start, - vma->vm_page_prot); - if (ret) - return ret; + vma->vm_pgoff += (ioaddr + pbm->io_space.start) >> PAGE_SHIFT; return 0; }