Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751428AbaLOVdd (ORCPT ); Mon, 15 Dec 2014 16:33:33 -0500 Received: from mx1.redhat.com ([209.132.183.28]:48708 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750809AbaLOVd1 (ORCPT ); Mon, 15 Dec 2014 16:33:27 -0500 Date: Mon, 15 Dec 2014 23:33:09 +0200 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: Rusty Russell , virtualization@lists.linux-foundation.org, linux-sh@vger.kernel.org, cornelia.huck@de.ibm.com, Michael S Tsirkin , Arnd Bergmann , linux-arch@vger.kernel.org Subject: [PATCH RFC 1/5] pci: add pci_iomap_range Message-ID: <1418679168-1011-2-git-send-email-mst@redhat.com> References: <1418679168-1011-1-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1418679168-1011-1-git-send-email-mst@redhat.com> X-Mutt-Fcc: =sent Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Michael S Tsirkin Virtio drivers should map the part of the BAR they need, not necessarily all of it. Signed-off-by: Michael S. Tsirkin Signed-off-by: Rusty Russell --- include/asm-generic/pci_iomap.h | 10 ++++++++++ lib/pci_iomap.c | 35 ++++++++++++++++++++++++++++++----- 2 files changed, 40 insertions(+), 5 deletions(-) diff --git a/include/asm-generic/pci_iomap.h b/include/asm-generic/pci_iomap.h index ce37349..7389c87 100644 --- a/include/asm-generic/pci_iomap.h +++ b/include/asm-generic/pci_iomap.h @@ -15,6 +15,9 @@ struct pci_dev; #ifdef CONFIG_PCI /* Create a virtual mapping cookie for a PCI BAR (memory or IO) */ extern void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long max); +extern void __iomem *pci_iomap_range(struct pci_dev *dev, int bar, + unsigned long offset, + unsigned long maxlen); /* Create a virtual mapping cookie for a port on a given PCI device. * Do not call this directly, it exists to make it easier for architectures * to override */ @@ -30,6 +33,13 @@ static inline void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned lon { return NULL; } + +static inline void __iomem *pci_iomap_range(struct pci_dev *dev, int bar, + unsigned long offset, + unsigned long maxlen) +{ + return NULL; +} #endif #endif /* __ASM_GENERIC_IO_H */ diff --git a/lib/pci_iomap.c b/lib/pci_iomap.c index 0d83ea8..bcce5f1 100644 --- a/lib/pci_iomap.c +++ b/lib/pci_iomap.c @@ -10,10 +10,11 @@ #ifdef CONFIG_PCI /** - * pci_iomap - create a virtual mapping cookie for a PCI BAR + * pci_iomap_range - create a virtual mapping cookie for a PCI BAR * @dev: PCI device that owns the BAR * @bar: BAR number - * @maxlen: length of the memory to map + * @offset: map memory at the given offset in BAR + * @maxlen: max length of the memory to map * * Using this function you will get a __iomem address to your device BAR. * You can access it using ioread*() and iowrite*(). These functions hide @@ -21,16 +22,21 @@ * you expect from them in the correct way. * * @maxlen specifies the maximum length to map. If you want to get access to - * the complete BAR without checking for its length first, pass %0 here. + * the complete BAR from offset to the end, pass %0 here. * */ -void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen) +void __iomem *pci_iomap_range(struct pci_dev *dev, + int bar, + unsigned long offset, + unsigned long maxlen) { resource_size_t start = pci_resource_start(dev, bar); resource_size_t len = pci_resource_len(dev, bar); unsigned long flags = pci_resource_flags(dev, bar); - if (!len || !start) + if (len <= offset || !start) return NULL; + len -= offset; + start += offset; if (maxlen && len > maxlen) len = maxlen; if (flags & IORESOURCE_IO) @@ -43,6 +49,25 @@ void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen) /* What? */ return NULL; } +EXPORT_SYMBOL(pci_iomap_range); +/** + * pci_iomap - create a virtual mapping cookie for a PCI BAR + * @dev: PCI device that owns the BAR + * @bar: BAR number + * @maxlen: length of the memory to map + * + * Using this function you will get a __iomem address to your device BAR. + * You can access it using ioread*() and iowrite*(). These functions hide + * the details if this is a MMIO or PIO address space and will just do what + * you expect from them in the correct way. + * + * @maxlen specifies the maximum length to map. If you want to get access to + * the complete BAR without checking for its length first, pass %0 here. + * */ +void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen) +{ + return pci_iomap_range(dev, bar, 0, maxlen); +} EXPORT_SYMBOL(pci_iomap); #endif /* CONFIG_PCI */ -- MST -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/