diff options
author | David Brown <davidb@codeaurora.org> | 2011-03-16 22:13:16 -0700 |
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committer | David Brown <davidb@codeaurora.org> | 2011-03-16 22:13:16 -0700 |
commit | 92c260f755c42337c550d8ac1f8ccd1b32bffb20 (patch) | |
tree | 6d04fefc1adeecabfb2b00c201e0db78fa2b5529 /arch/arm/include/asm/highmem.h | |
parent | 8e76a80960bf06c245160a484d5a363ca6b520bb (diff) | |
parent | 05e34754518b6a90d5c392790c032575fab12d66 (diff) |
Merge remote branch 'rmk/for-linus' into for-linus
* rmk/for-linus: (1557 commits)
ARM: 6806/1: irq: introduce entry and exit functions for chained handlers
ARM: 6781/1: Thumb-2: Work around buggy Thumb-2 short branch relocations in gas
ARM: 6747/1: P2V: Thumb2 support
ARM: 6798/1: aout-core: zero thread debug registers in a.out core dump
ARM: 6796/1: Footbridge: Fix I/O mappings for NOMMU mode
ARM: 6784/1: errata: no automatic Store Buffer drain on Cortex-A9
ARM: 6772/1: errata: possible fault MMU translations following an ASID switch
ARM: 6776/1: mach-ux500: activate fix for errata 753970
ARM: 6794/1: SPEAr: Append UL to device address macros.
ARM: 6793/1: SPEAr: Remove unused *_SIZE macros from spear*.h files
ARM: 6792/1: SPEAr: Replace SIZE macro's with SZ_4K macros
ARM: 6791/1: SPEAr3xx: Declare device structures after shirq code
ARM: 6790/1: SPEAr: Clock Framework: Rename usbd clock and align apb_clk entry
ARM: 6789/1: SPEAr3xx: Rename sdio to sdhci
ARM: 6788/1: SPEAr: Include mach/hardware.h instead of mach/spear.h
ARM: 6787/1: SPEAr: Reorder #includes in .h & .c files.
ARM: 6681/1: SPEAr: add debugfs support to clk API
ARM: 6703/1: SPEAr: update clk API support
ARM: 6679/1: SPEAr: make clk API functions more generic
ARM: 6737/1: SPEAr: formalized timer support
...
Conflicts:
arch/arm/mach-msm/board-msm7x27.c
arch/arm/mach-msm/board-msm7x30.c
arch/arm/mach-msm/board-qsd8x50.c
arch/arm/mach-msm/board-sapphire.c
arch/arm/mach-msm/include/mach/memory.h
Diffstat (limited to 'arch/arm/include/asm/highmem.h')
-rw-r--r-- | arch/arm/include/asm/highmem.h | 29 |
1 files changed, 27 insertions, 2 deletions
diff --git a/arch/arm/include/asm/highmem.h b/arch/arm/include/asm/highmem.h index 7080e2c8fa6..a4edd19dd3d 100644 --- a/arch/arm/include/asm/highmem.h +++ b/arch/arm/include/asm/highmem.h @@ -19,11 +19,36 @@ extern pte_t *pkmap_page_table; +extern void *kmap_high(struct page *page); +extern void kunmap_high(struct page *page); + +/* + * The reason for kmap_high_get() is to ensure that the currently kmap'd + * page usage count does not decrease to zero while we're using its + * existing virtual mapping in an atomic context. With a VIVT cache this + * is essential to do, but with a VIPT cache this is only an optimization + * so not to pay the price of establishing a second mapping if an existing + * one can be used. However, on platforms without hardware TLB maintenance + * broadcast, we simply cannot use ARCH_NEEDS_KMAP_HIGH_GET at all since + * the locking involved must also disable IRQs which is incompatible with + * the IPI mechanism used by global TLB operations. + */ #define ARCH_NEEDS_KMAP_HIGH_GET +#if defined(CONFIG_SMP) && defined(CONFIG_CPU_TLB_V6) +#undef ARCH_NEEDS_KMAP_HIGH_GET +#if defined(CONFIG_HIGHMEM) && defined(CONFIG_CPU_CACHE_VIVT) +#error "The sum of features in your kernel config cannot be supported together" +#endif +#endif -extern void *kmap_high(struct page *page); +#ifdef ARCH_NEEDS_KMAP_HIGH_GET extern void *kmap_high_get(struct page *page); -extern void kunmap_high(struct page *page); +#else +static inline void *kmap_high_get(struct page *page) +{ + return NULL; +} +#endif /* * The following functions are already defined by <linux/highmem.h> |