It is very useful to release I/O resources so that the same I/O resources can be allocated again (pci_remap_iospace), like in PCI hotplug removal scenario. Therefore this patch implements new pci_unmap_iospace call which unmaps I/O space as the symmetry to pci_remap_iospace.
Signed-off-by: Sinan Kaya okaya@codeaurora.org Signed-off-by: Tomasz Nowicki tn@semihalf.com --- drivers/pci/pci.c | 24 ++++++++++++++++++++++++ include/linux/pci.h | 1 + 2 files changed, 25 insertions(+)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index bc0c914..ff97a0b 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -25,6 +25,7 @@ #include <linux/device.h> #include <linux/pm_runtime.h> #include <linux/pci_hotplug.h> +#include <linux/vmalloc.h> #include <asm/setup.h> #include <linux/aer.h> #include "pci.h" @@ -3167,6 +3168,29 @@ int __weak pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr) #endif }
+/** + * pci_unmap_iospace - Unmap the memory mapped I/O space + * @res: resource to be unmapped + * + * Unmap the CPU virtual address @res from virtual address space. + * Only architectures that have memory mapped IO functions defined + * (and the PCI_IOBASE value defined) should call this function. + */ +void pci_unmap_iospace(struct resource *res) +{ +#if defined(PCI_IOBASE) && defined(CONFIG_MMU) + unsigned long vaddr = (unsigned long)PCI_IOBASE + res->start; + + unmap_kernel_range(vaddr, resource_size(res)); +#else + /* + * This architecture does not have memory mapped I/O space, + * so this function should never be called. + */ + WARN_ONCE(1, "This architecture does not support memory mapped I/O\n"); +#endif +} + static void __pci_set_master(struct pci_dev *dev, bool enable) { u16 old_cmd, cmd; diff --git a/include/linux/pci.h b/include/linux/pci.h index d2a57f3..d6ea6ce 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1169,6 +1169,7 @@ int pci_register_io_range(phys_addr_t addr, resource_size_t size); unsigned long pci_address_to_pio(phys_addr_t addr); phys_addr_t pci_pio_to_address(unsigned long pio); int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr); +void pci_unmap_iospace(struct resource *res);
static inline pci_bus_addr_t pci_bus_address(struct pci_dev *pdev, int bar) {