In current implementation, we used ARM-specific flag, that is, VM_ARM_STATIC_MAPPING, for distinguishing ARM specific static mapped area. The purpose of static mapped area is to re-use static mapped area when entire physical address range of the ioremap request can be covered by this area. This implementation causes needless overhead for some cases. For example, assume that there is only one static mapped area and vmlist has 300 areas. Every time we call ioremap, we check 300 areas for deciding whether it is matched or not. Moreover, even if there is no static mapped area and vmlist has 300 areas, every time we call ioremap, we check 300 areas in now. If we construct a extra list for static mapped area, we can eliminate above mentioned overhead. With a extra list, if there is one static mapped area, we just check only one area and proceed next operation quickly. In fact, it is not a critical problem, because ioremap is not frequently used. But reducing overhead is better idea. Another reason for doing this work is for removing architecture dependency on vmalloc layer. I think that vmlist and vmlist_lock is internal data structure for vmalloc layer. Some codes for debugging and stat inevitably use vmlist and vmlist_lock. But it is preferable that they are used as least as possible in outside of vmalloc.c Changelog v1->v2: [2/3]: patch description is improved. Rebased on v3.7-rc7 Joonsoo Kim (3): ARM: vmregion: remove vmregion code entirely ARM: static_vm: introduce an infrastructure for static mapped area ARM: mm: use static_vm for managing static mapped areas arch/arm/include/asm/mach/static_vm.h | 51 ++++++++ arch/arm/mm/Makefile | 2 +- arch/arm/mm/ioremap.c | 69 ++++------- arch/arm/mm/mm.h | 10 -- arch/arm/mm/mmu.c | 55 +++++---- arch/arm/mm/static_vm.c | 97 ++++++++++++++++ arch/arm/mm/vmregion.c | 205 --------------------------------- arch/arm/mm/vmregion.h | 31 ----- 8 files changed, 208 insertions(+), 312 deletions(-) create mode 100644 arch/arm/include/asm/mach/static_vm.h create mode 100644 arch/arm/mm/static_vm.c delete mode 100644 arch/arm/mm/vmregion.c delete mode 100644 arch/arm/mm/vmregion.h -- 1.7.9.5 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>