From 013de2d6671d89de3397904749c86a69ac0686f7 Mon Sep 17 00:00:00 2001 From: Guo Ren Date: Wed, 5 Sep 2018 14:25:12 +0800 Subject: csky: MMU and page table management MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This patch adds files related to memory management and here is our memory-layout: Fixmap : 0xffc02000 – 0xfffff000 (4 MB - 12KB) Pkmap : 0xff800000 – 0xffc00000 (4 MB) Vmalloc : 0xf0200000 – 0xff000000 (238 MB) Lowmem : 0x80000000 – 0xc0000000 (1GB) abiv1 CPU (CK610) is VIPT cache and it doesn't support highmem. abiv2 CPUs are all PIPT cache and they could support highmem. Lowmem is directly mapped by msa0 & msa1 reg, and we needn't setup memory page table for it. Link:https://lore.kernel.org/lkml/20180518215548.GH17671@n2100.armlinux.org.uk/ Signed-off-by: Guo Ren Cc: Christoph Hellwig Reviewed-by: Arnd Bergmann --- arch/csky/abiv1/mmap.c | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 66 insertions(+) create mode 100644 arch/csky/abiv1/mmap.c (limited to 'arch/csky/abiv1/mmap.c') diff --git a/arch/csky/abiv1/mmap.c b/arch/csky/abiv1/mmap.c new file mode 100644 index 000000000000..b462fd50b23a --- /dev/null +++ b/arch/csky/abiv1/mmap.c @@ -0,0 +1,66 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. + +#include +#include +#include +#include +#include +#include +#include + +unsigned long shm_align_mask = (0x4000 >> 1) - 1; /* Sane caches */ + +#define COLOUR_ALIGN(addr, pgoff) \ + ((((addr) + shm_align_mask) & ~shm_align_mask) + \ + (((pgoff) << PAGE_SHIFT) & shm_align_mask)) + +unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, + unsigned long len, unsigned long pgoff, unsigned long flags) +{ + struct vm_area_struct *vmm; + int do_color_align; + + if (flags & MAP_FIXED) { + /* + * We do not accept a shared mapping if it would violate + * cache aliasing constraints. + */ + if ((flags & MAP_SHARED) && + ((addr - (pgoff << PAGE_SHIFT)) & shm_align_mask)) + return -EINVAL; + return addr; + } + + if (len > TASK_SIZE) + return -ENOMEM; + do_color_align = 0; + if (filp || (flags & MAP_SHARED)) + do_color_align = 1; + if (addr) { + if (do_color_align) + addr = COLOUR_ALIGN(addr, pgoff); + else + addr = PAGE_ALIGN(addr); + vmm = find_vma(current->mm, addr); + if (TASK_SIZE - len >= addr && + (!vmm || addr + len <= vmm->vm_start)) + return addr; + } + addr = TASK_UNMAPPED_BASE; + if (do_color_align) + addr = COLOUR_ALIGN(addr, pgoff); + else + addr = PAGE_ALIGN(addr); + + for (vmm = find_vma(current->mm, addr); ; vmm = vmm->vm_next) { + /* At this point: (!vmm || addr < vmm->vm_end). */ + if (TASK_SIZE - len < addr) + return -ENOMEM; + if (!vmm || addr + len <= vmm->vm_start) + return addr; + addr = vmm->vm_end; + if (do_color_align) + addr = COLOUR_ALIGN(addr, pgoff); + } +} -- cgit v1.2.3