arm: Use the generic devmem_is_allowed()

This is exactly the same as the arm64 version, which I recently copied
into lib/ for use by the RISC-V port.

Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index e00d94b..16095d3 100644 (file)
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -5,7 +5,6 @@ config ARM
        select ARCH_32BIT_OFF_T
        select ARCH_HAS_BINFMT_FLAT
        select ARCH_HAS_DEBUG_VIRTUAL if MMU
-       select ARCH_HAS_DEVMEM_IS_ALLOWED
        select ARCH_HAS_DMA_WRITE_COMBINE if !ARM_DMA_MEM_BUFFERABLE
        select ARCH_HAS_ELF_RANDOMIZE
        select ARCH_HAS_FORTIFY_SOURCE
@@ -55,6 +54,7 @@ config ARM
        select GENERIC_IRQ_PROBE
        select GENERIC_IRQ_SHOW
        select GENERIC_IRQ_SHOW_LEVEL
+       select GENERIC_LIB_DEVMEM_IS_ALLOWED
        select GENERIC_PCI_IOMAP
        select GENERIC_SCHED_CLOCK
        select GENERIC_SMP_IDLE_THREAD

diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h
index ab2b654..fc74812 100644 (file)
--- a/arch/arm/include/asm/io.h
+++ b/arch/arm/include/asm/io.h
@@ -441,7 +441,6 @@ extern void pci_iounmap(struct pci_dev *dev, void __iomem *addr);
 #define ARCH_HAS_VALID_PHYS_ADDR_RANGE
 extern int valid_phys_addr_range(phys_addr_t addr, size_t size);
 extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
-extern int devmem_is_allowed(unsigned long pfn);
 #endif
 
 /*

diff --git a/arch/arm/mm/mmap.c b/arch/arm/mm/mmap.c
index b8d912a..a0f8a0c 100644 (file)
--- a/arch/arm/mm/mmap.c
+++ b/arch/arm/mm/mmap.c
@@ -165,25 +165,3 @@ int valid_mmap_phys_addr_range(unsigned long pfn, size_t size)
 {
        return (pfn + (size >> PAGE_SHIFT)) <= (1 + (PHYS_MASK >> PAGE_SHIFT));
 }
-
-#ifdef CONFIG_STRICT_DEVMEM
-
-#include <linux/ioport.h>
-
-/*
- * devmem_is_allowed() checks to see if /dev/mem access to a certain
- * address is valid. The argument is a physical page number.
- * We mimic x86 here by disallowing access to system RAM as well as
- * device-exclusive MMIO regions. This effectively disable read()/write()
- * on /dev/mem.
- */
-int devmem_is_allowed(unsigned long pfn)
-{
-       if (iomem_is_exclusive(pfn << PAGE_SHIFT))
-               return 0;
-       if (!page_is_ram(pfn))
-               return 1;
-       return 0;
-}
-
-#endif