From a67462fc9de8b958d6a2c2c34d0195733a8c61a6 Mon Sep 17 00:00:00 2001 From: Krzysztof Wilczyński Date: Tue, 13 Jul 2021 10:24:36 +0000 Subject: PCI: Refactor pci_ioremap_bar() and pci_ioremap_wc_bar() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit pci_ioremap_bar() and pci_ioremap_wc_bar() shared similar implementations but differed in unimportant ways. Align them by adding a shared helper, __pci_ioremap_resource(). Upgrade warning message to error level, since it indicates a driver defect. Remove WARN_ON() from WC path in favor of the error message. [bhelgaas: commit log, use ioremap() since pci_iomap_range() doesn't add anything] Link: https://lore.kernel.org/r/20210713102436.304693-1-kw@linux.com Signed-off-by: Krzysztof Wilczyński Signed-off-by: Bjorn Helgaas --- drivers/pci/pci.c | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index aacf575c15cf..2f519074f0f8 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -206,32 +206,36 @@ int pci_status_get_and_clear_errors(struct pci_dev *pdev) EXPORT_SYMBOL_GPL(pci_status_get_and_clear_errors); #ifdef CONFIG_HAS_IOMEM -void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar) +static void __iomem *__pci_ioremap_resource(struct pci_dev *pdev, int bar, + bool write_combine) { struct resource *res = &pdev->resource[bar]; + resource_size_t start = res->start; + resource_size_t size = resource_size(res); /* * Make sure the BAR is actually a memory resource, not an IO resource */ if (res->flags & IORESOURCE_UNSET || !(res->flags & IORESOURCE_MEM)) { - pci_warn(pdev, "can't ioremap BAR %d: %pR\n", bar, res); + pci_err(pdev, "can't ioremap BAR %d: %pR\n", bar, res); return NULL; } - return ioremap(res->start, resource_size(res)); + + if (write_combine) + return ioremap_wc(start, size); + + return ioremap(start, size); +} + +void __iomem *pci_ioremap_bar(struct pci_dev *pdev, int bar) +{ + return __pci_ioremap_resource(pdev, bar, false); } EXPORT_SYMBOL_GPL(pci_ioremap_bar); void __iomem *pci_ioremap_wc_bar(struct pci_dev *pdev, int bar) { - /* - * Make sure the BAR is actually a memory resource, not an IO resource - */ - if (!(pci_resource_flags(pdev, bar) & IORESOURCE_MEM)) { - WARN_ON(1); - return NULL; - } - return ioremap_wc(pci_resource_start(pdev, bar), - pci_resource_len(pdev, bar)); + return __pci_ioremap_resource(pdev, bar, true); } EXPORT_SYMBOL_GPL(pci_ioremap_wc_bar); #endif -- cgit v1.2.3 From ca32b5310a1a3835f81f498367f1bb7450c8b67b Mon Sep 17 00:00:00 2001 From: Zhen Lei Date: Tue, 13 Jul 2021 15:22:36 +0800 Subject: PCI: Optimize pci_resource_len() to reduce kernel size pci_resource_end() can be 0 only when pci_resource_start() is 0. Otherwise, it is definitely an error. In this case, pci_resource_len() should be regarded as 0. Therefore, determining whether pci_resource_start() and pci_resource_end() are both 0 can be reduced to determining only whether pci_resource_end() is 0. Although only one condition judgment is reduced, the macro function pci_resource_len() is widely referenced in the kernel. I used defconfig to compile the latest kernel on X86, and its binary code size was reduced by about 3KB. Before: [ 2] .rela.text RELA 0000000000000000 093bfcb0 0000000001a67168 0000000000000018 I 68 1 8 After: [ 2] .rela.text RELA 0000000000000000 093bfcb0 0000000001a66598 0000000000000018 I 68 1 8 Link: https://lore.kernel.org/r/20210713072236.3043-1-thunder.leizhen@huawei.com Signed-off-by: Zhen Lei Signed-off-by: Bjorn Helgaas --- include/linux/pci.h | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/include/linux/pci.h b/include/linux/pci.h index 540b377ca8f6..23ef1a15eb5d 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1881,9 +1881,7 @@ int pci_iobar_pfn(struct pci_dev *pdev, int bar, struct vm_area_struct *vma); #define pci_resource_end(dev, bar) ((dev)->resource[(bar)].end) #define pci_resource_flags(dev, bar) ((dev)->resource[(bar)].flags) #define pci_resource_len(dev,bar) \ - ((pci_resource_start((dev), (bar)) == 0 && \ - pci_resource_end((dev), (bar)) == \ - pci_resource_start((dev), (bar))) ? 0 : \ + ((pci_resource_end((dev), (bar)) == 0) ? 0 : \ \ (pci_resource_end((dev), (bar)) - \ pci_resource_start((dev), (bar)) + 1)) -- cgit v1.2.3