From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ed1-f68.google.com ([209.85.208.68]:44988 "EHLO mail-ed1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388876AbfIETCT (ORCPT ); Thu, 5 Sep 2019 15:02:19 -0400 Subject: Re: [PATCH v2 00/10] Add definition for the number of standard PCI BARs References: <20190816092437.31846-1-efremov@linux.com> <20190816105128.GD14111@e119886-lin.cambridge.arm.com> From: Denis Efremov Message-ID: <5d8cdc6b-f8c9-c3f1-e11d-13b3a7eb5b26@linux.com> Date: Thu, 5 Sep 2019 22:02:13 +0300 MIME-Version: 1.0 In-Reply-To: <20190816105128.GD14111@e119886-lin.cambridge.arm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-s390-owner@vger.kernel.org List-ID: To: Andrew Murray Cc: Bjorn Helgaas , linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, Sebastian Ott , Gerald Schaefer , "H. Peter Anvin" , Giuseppe Cavallaro , Alexandre Torgue , Matt Porter , Alexandre Bounine , Peter Jones , Bartlomiej Zolnierkiewicz , Cornelia Huck , Alex Williamson , Jose Abreu , kvm@vger.kernel.org, linux-fbdev@vger.kernel.org, netdev@vger.kernel.org, x86@kernel.org, linux-s390@vger.kernel.org On 16.08.2019 13:51, Andrew Murray wrote: > On Fri, Aug 16, 2019 at 12:24:27PM +0300, Denis Efremov wrote: >> Code that iterates over all standard PCI BARs typically uses >> PCI_STD_RESOURCE_END, but this is error-prone because it requires >> "i <= PCI_STD_RESOURCE_END" rather than something like >> "i < PCI_STD_NUM_BARS". We could add such a definition and use it the same >> way PCI_SRIOV_NUM_BARS is used. There is already the definition >> PCI_BAR_COUNT for s390 only. Thus, this patchset introduces it globally. >> >> Changes in v2: >> - Reverse checks in pci_iomap_range,pci_iomap_wc_range. >> - Refactor loops in vfio_pci to keep PCI_STD_RESOURCES. >> - Add 2 new patches to replace the magic constant with new define. >> - Split net patch in v1 to separate stmmac and dwc-xlgmac patches. >> >> Denis Efremov (10): >> PCI: Add define for the number of standard PCI BARs >> s390/pci: Loop using PCI_STD_NUM_BARS >> x86/PCI: Loop using PCI_STD_NUM_BARS >> stmmac: pci: Loop using PCI_STD_NUM_BARS >> net: dwc-xlgmac: Loop using PCI_STD_NUM_BARS >> rapidio/tsi721: Loop using PCI_STD_NUM_BARS >> efifb: Loop using PCI_STD_NUM_BARS >> vfio_pci: Loop using PCI_STD_NUM_BARS >> PCI: hv: Use PCI_STD_NUM_BARS >> PCI: Use PCI_STD_NUM_BARS >> >> arch/s390/include/asm/pci.h | 5 +---- >> arch/s390/include/asm/pci_clp.h | 6 +++--- >> arch/s390/pci/pci.c | 16 ++++++++-------- >> arch/s390/pci/pci_clp.c | 6 +++--- >> arch/x86/pci/common.c | 2 +- >> drivers/net/ethernet/stmicro/stmmac/stmmac_pci.c | 4 ++-- >> drivers/net/ethernet/synopsys/dwc-xlgmac-pci.c | 2 +- >> drivers/pci/controller/pci-hyperv.c | 10 +++++----- >> drivers/pci/pci.c | 11 ++++++----- >> drivers/pci/quirks.c | 4 ++-- >> drivers/rapidio/devices/tsi721.c | 2 +- >> drivers/vfio/pci/vfio_pci.c | 11 +++++++---- >> drivers/vfio/pci/vfio_pci_config.c | 10 ++++++---- >> drivers/vfio/pci/vfio_pci_private.h | 4 ++-- >> drivers/video/fbdev/efifb.c | 2 +- >> include/linux/pci.h | 2 +- >> include/uapi/linux/pci_regs.h | 1 + >> 17 files changed, 51 insertions(+), 47 deletions(-) > > I've come across a few more places where this change can be made. There > may be multiple instances in the same file, but only the first is shown > below: > > drivers/misc/pci_endpoint_test.c: for (bar = BAR_0; bar <= BAR_5; bar++) { > drivers/net/ethernet/intel/e1000/e1000_main.c: for (i = BAR_1; i <= BAR_5; i++) { > drivers/net/ethernet/intel/ixgb/ixgb_main.c: for (i = BAR_1; i <= BAR_5; i++) { > drivers/pci/controller/dwc/pci-dra7xx.c: for (bar = BAR_0; bar <= BAR_5; bar++) > drivers/pci/controller/dwc/pci-layerscape-ep.c: for (bar = BAR_0; bar <= BAR_5; bar++) > drivers/pci/controller/dwc/pcie-artpec6.c: for (bar = BAR_0; bar <= BAR_5; bar++) > drivers/pci/controller/dwc/pcie-designware-plat.c: for (bar = BAR_0; bar <= BAR_5; bar++) > drivers/pci/endpoint/functions/pci-epf-test.c: for (bar = BAR_0; bar <= BAR_5; bar++) { > include/linux/pci-epc.h: u64 bar_fixed_size[BAR_5 + 1]; > drivers/scsi/pm8001/pm8001_hwi.c: for (bar = 0; bar < 6; bar++) { > drivers/scsi/pm8001/pm8001_init.c: for (bar = 0; bar < 6; bar++) { > drivers/ata/sata_nv.c: for (bar = 0; bar < 6; bar++) > drivers/video/fbdev/core/fbmem.c: for (idx = 0, bar = 0; bar < PCI_ROM_RESOURCE; bar++) { > drivers/staging/gasket/gasket_core.c: for (i = 0; i < GASKET_NUM_BARS; i++) { > drivers/tty/serial/8250/8250_pci.c: for (i = 0; i < PCI_NUM_BAR_RESOURCES; i++) { <----------- > > It looks like BARs are often iterated with PCI_NUM_BAR_RESOURCES, there > are a load of these too found with: > > git grep PCI_ROM_RESOURCE | grep "< " > > I'm happy to share patches if preferred. > I'm not sure about lib/devres.c 265:#define PCIM_IOMAP_MAX PCI_ROM_RESOURCE 268: void __iomem *table[PCIM_IOMAP_MAX]; 277: for (i = 0; i < PCIM_IOMAP_MAX; i++) 324: BUG_ON(bar >= PCIM_IOMAP_MAX); 352: for (i = 0; i < PCIM_IOMAP_MAX; i++) 455: for (i = 0; i < PCIM_IOMAP_MAX; i++) { Is it worth changing? #define PCIM_IOMAP_MAX PCI_STD_NUM_BARS Thanks, Denis