Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751378AbaLOVda (ORCPT ); Mon, 15 Dec 2014 16:33:30 -0500 Received: from mx1.redhat.com ([209.132.183.28]:50678 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750820AbaLOVd1 (ORCPT ); Mon, 15 Dec 2014 16:33:27 -0500 Date: Mon, 15 Dec 2014 23:33:13 +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 , Martin Schwidefsky , Heiko Carstens , linux390@de.ibm.com, Sebastian Ott , Gerald Schaefer , linux-s390@vger.kernel.org Subject: [PATCH RFC 2/5] s390: add pci_iomap_range Message-ID: <1418679168-1011-3-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 range they need, not necessarily all of it. To this end, support mapping ranges within BAR on s390. Since multiple ranges can now be mapped within a BAR, we keep track of the number of mappings created, and only clear out the mapping for a BAR when this number reaches 0. Signed-off-by: Michael S. Tsirkin --- arch/s390/include/asm/pci_io.h | 1 + arch/s390/pci/pci.c | 34 +++++++++++++++++++++++++++------- 2 files changed, 28 insertions(+), 7 deletions(-) diff --git a/arch/s390/include/asm/pci_io.h b/arch/s390/include/asm/pci_io.h index d194d54..25228b3 100644 --- a/arch/s390/include/asm/pci_io.h +++ b/arch/s390/include/asm/pci_io.h @@ -16,6 +16,7 @@ struct zpci_iomap_entry { u32 fh; u8 bar; + u16 count; }; extern struct zpci_iomap_entry *zpci_iomap_start; diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c index 2fa7b14..51cb653 100644 --- a/arch/s390/pci/pci.c +++ b/arch/s390/pci/pci.c @@ -259,7 +259,10 @@ void __iowrite64_copy(void __iomem *to, const void *from, size_t count) } /* Create a virtual mapping cookie for a PCI BAR */ -void __iomem *pci_iomap(struct pci_dev *pdev, int bar, unsigned long max) +void __iomem *pci_iomap_range(struct pci_dev *pdev, + int bar, + unsigned long offset, + unsigned long max) { struct zpci_dev *zdev = get_zdev(pdev); u64 addr; @@ -270,14 +273,27 @@ void __iomem *pci_iomap(struct pci_dev *pdev, int bar, unsigned long max) idx = zdev->bars[bar].map_idx; spin_lock(&zpci_iomap_lock); - zpci_iomap_start[idx].fh = zdev->fh; - zpci_iomap_start[idx].bar = bar; + if (zpci_iomap_start[idx].count++) { + BUG_ON(zpci_iomap_start[idx].fh != zdev->fh || + zpci_iomap_start[idx].bar != bar); + } else { + zpci_iomap_start[idx].fh = zdev->fh; + zpci_iomap_start[idx].bar = bar; + } + /* Detect overrun */ + BUG_ON(!zpci_iomap_start[idx].count); spin_unlock(&zpci_iomap_lock); addr = ZPCI_IOMAP_ADDR_BASE | ((u64) idx << 48); - return (void __iomem *) addr; + return (void __iomem *) addr + offset; } -EXPORT_SYMBOL_GPL(pci_iomap); +EXPORT_SYMBOL_GPL(pci_iomap_range); + +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); void pci_iounmap(struct pci_dev *pdev, void __iomem *addr) { @@ -285,8 +301,12 @@ void pci_iounmap(struct pci_dev *pdev, void __iomem *addr) idx = (((__force u64) addr) & ~ZPCI_IOMAP_ADDR_BASE) >> 48; spin_lock(&zpci_iomap_lock); - zpci_iomap_start[idx].fh = 0; - zpci_iomap_start[idx].bar = 0; + /* Detect underrun */ + BUG_ON(!zpci_iomap_start[idx].count); + if (!--zpci_iomap_start[idx].count) { + zpci_iomap_start[idx].fh = 0; + zpci_iomap_start[idx].bar = 0; + } spin_unlock(&zpci_iomap_lock); } EXPORT_SYMBOL_GPL(pci_iounmap); -- 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/