diff options
author | Huacai Chen <chenhuacai@loongson.cn> | 2022-05-31 18:04:11 +0800 |
---|---|---|
committer | Huacai Chen <chenhuacai@loongson.cn> | 2022-06-03 20:09:28 +0800 |
commit | 09cfefb7fa70c3af011b0db0a513fd80b2f18abc (patch) | |
tree | fc1a269ecba1f88cabb2e79ee92251612ed6605a /arch/loongarch/mm/mmap.c | |
parent | 803b0fc5c3f2baa6e54978cd576407896f789b08 (diff) | |
download | linux-stable-09cfefb7fa70c3af011b0db0a513fd80b2f18abc.tar.gz linux-stable-09cfefb7fa70c3af011b0db0a513fd80b2f18abc.tar.bz2 linux-stable-09cfefb7fa70c3af011b0db0a513fd80b2f18abc.zip |
LoongArch: Add memory management
Add memory management support for LoongArch, including: cache and tlb
management, page fault handling and ioremap/mmap support.
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Diffstat (limited to 'arch/loongarch/mm/mmap.c')
-rw-r--r-- | arch/loongarch/mm/mmap.c | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/arch/loongarch/mm/mmap.c b/arch/loongarch/mm/mmap.c new file mode 100644 index 000000000000..52e40f0ba732 --- /dev/null +++ b/arch/loongarch/mm/mmap.c @@ -0,0 +1,125 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ +#include <linux/compiler.h> +#include <linux/elf-randomize.h> +#include <linux/errno.h> +#include <linux/mm.h> +#include <linux/mman.h> +#include <linux/export.h> +#include <linux/personality.h> +#include <linux/random.h> +#include <linux/sched/signal.h> +#include <linux/sched/mm.h> + +unsigned long shm_align_mask = PAGE_SIZE - 1; /* Sane caches */ +EXPORT_SYMBOL(shm_align_mask); + +#define COLOUR_ALIGN(addr, pgoff) \ + ((((addr) + shm_align_mask) & ~shm_align_mask) + \ + (((pgoff) << PAGE_SHIFT) & shm_align_mask)) + +enum mmap_allocation_direction {UP, DOWN}; + +static unsigned long arch_get_unmapped_area_common(struct file *filp, + unsigned long addr0, unsigned long len, unsigned long pgoff, + unsigned long flags, enum mmap_allocation_direction dir) +{ + struct mm_struct *mm = current->mm; + struct vm_area_struct *vma; + unsigned long addr = addr0; + int do_color_align; + struct vm_unmapped_area_info info; + + if (unlikely(len > TASK_SIZE)) + return -ENOMEM; + + if (flags & MAP_FIXED) { + /* Even MAP_FIXED mappings must reside within TASK_SIZE */ + if (TASK_SIZE - len < addr) + return -EINVAL; + + /* + * 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; + } + + do_color_align = 0; + if (filp || (flags & MAP_SHARED)) + do_color_align = 1; + + /* requesting a specific address */ + if (addr) { + if (do_color_align) + addr = COLOUR_ALIGN(addr, pgoff); + else + addr = PAGE_ALIGN(addr); + + vma = find_vma(mm, addr); + if (TASK_SIZE - len >= addr && + (!vma || addr + len <= vm_start_gap(vma))) + return addr; + } + + info.length = len; + info.align_mask = do_color_align ? (PAGE_MASK & shm_align_mask) : 0; + info.align_offset = pgoff << PAGE_SHIFT; + + if (dir == DOWN) { + info.flags = VM_UNMAPPED_AREA_TOPDOWN; + info.low_limit = PAGE_SIZE; + info.high_limit = mm->mmap_base; + addr = vm_unmapped_area(&info); + + if (!(addr & ~PAGE_MASK)) + return addr; + + /* + * A failed mmap() very likely causes application failure, + * so fall back to the bottom-up function here. This scenario + * can happen with large stack limits and large mmap() + * allocations. + */ + } + + info.flags = 0; + info.low_limit = mm->mmap_base; + info.high_limit = TASK_SIZE; + return vm_unmapped_area(&info); +} + +unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr0, + unsigned long len, unsigned long pgoff, unsigned long flags) +{ + return arch_get_unmapped_area_common(filp, + addr0, len, pgoff, flags, UP); +} + +/* + * There is no need to export this but sched.h declares the function as + * extern so making it static here results in an error. + */ +unsigned long arch_get_unmapped_area_topdown(struct file *filp, + unsigned long addr0, unsigned long len, unsigned long pgoff, + unsigned long flags) +{ + return arch_get_unmapped_area_common(filp, + addr0, len, pgoff, flags, DOWN); +} + +int __virt_addr_valid(volatile void *kaddr) +{ + unsigned long vaddr = (unsigned long)kaddr; + + if ((vaddr < PAGE_OFFSET) || (vaddr >= vm_map_base)) + return 0; + + return pfn_valid(PFN_DOWN(virt_to_phys(kaddr))); +} +EXPORT_SYMBOL_GPL(__virt_addr_valid); |