For arches that do not select CONFIG_GENERIC_IOMAP, the current pci_iounmap() function does nothing causing obvious memory leaks for mapped regions that are backed by MMIO physical space. In order to detect if a mapped pointer is IO vs MMIO, a check must made available to the pci_iounmap() function so that it can actually detect whether the pointer has to be unmapped. In configurations where CONFIG_HAS_IOPORT_MAP && !CONFIG_GENERIC_IOMAP, a mapped port is detected using an ioport_map() stub defined in asm-generic/io.h. Use the same logic to implement a stub (ie __pci_ioport_unmap()) that detects if the passed in pointer in pci_iounmap() is IO vs MMIO to iounmap conditionally and call it in pci_iounmap() fixing the issue. Leave __pci_ioport_unmap() as a NOP for all other config options. Reported-by: George Cherian <george.cherian@xxxxxxxxxxx> Link: https://lore.kernel.org/lkml/20200905024811.74701-1-yangyingliang@xxxxxxxxxx Link: https://lore.kernel.org/lkml/20200824132046.3114383-1-george.cherian@xxxxxxxxxxx Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Cc: George Cherian <george.cherian@xxxxxxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Yang Yingliang <yangyingliang@xxxxxxxxxx> --- include/asm-generic/io.h | 39 +++++++++++++++++++++++++++------------ 1 file changed, 27 insertions(+), 12 deletions(-) diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h index dabf8cb7203b..9ea83d80eb6f 100644 --- a/include/asm-generic/io.h +++ b/include/asm-generic/io.h @@ -911,18 +911,6 @@ static inline void iowrite64_rep(volatile void __iomem *addr, #include <linux/vmalloc.h> #define __io_virt(x) ((void __force *)(x)) -#ifndef CONFIG_GENERIC_IOMAP -struct pci_dev; -extern void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long max); - -#ifndef pci_iounmap -#define pci_iounmap pci_iounmap -static inline void pci_iounmap(struct pci_dev *dev, void __iomem *p) -{ -} -#endif -#endif /* CONFIG_GENERIC_IOMAP */ - /* * Change virtual addresses to physical addresses and vv. * These are pretty trivial @@ -1016,6 +1004,16 @@ static inline void __iomem *ioport_map(unsigned long port, unsigned int nr) port &= IO_SPACE_LIMIT; return (port > MMIO_UPPER_LIMIT) ? NULL : PCI_IOBASE + port; } +#define __pci_ioport_unmap __pci_ioport_unmap +static inline void __pci_ioport_unmap(void __iomem *p) +{ + uintptr_t start = (uintptr_t) PCI_IOBASE; + uintptr_t addr = (uintptr_t) p; + + if (addr >= start && addr < start + IO_SPACE_LIMIT) + return; + iounmap(p); +} #endif #ifndef ioport_unmap @@ -1030,6 +1028,23 @@ extern void ioport_unmap(void __iomem *p); #endif /* CONFIG_GENERIC_IOMAP */ #endif /* CONFIG_HAS_IOPORT_MAP */ +#ifndef CONFIG_GENERIC_IOMAP +struct pci_dev; +extern void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long max); + +#ifndef __pci_ioport_unmap +static inline void __pci_ioport_unmap(void __iomem *p) {} +#endif + +#ifndef pci_iounmap +#define pci_iounmap pci_iounmap +static inline void pci_iounmap(struct pci_dev *dev, void __iomem *p) +{ + __pci_ioport_unmap(p); +} +#endif +#endif /* CONFIG_GENERIC_IOMAP */ + /* * Convert a virtual cached pointer to an uncached pointer */ -- 2.26.1
