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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /arch/loongarch/mm/mmap.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/loongarch/mm/mmap.c')
-rw-r--r-- | arch/loongarch/mm/mmap.c | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/arch/loongarch/mm/mmap.c b/arch/loongarch/mm/mmap.c new file mode 100644 index 0000000000..a9630a81b3 --- /dev/null +++ b/arch/loongarch/mm/mmap.c @@ -0,0 +1,146 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ +#include <linux/export.h> +#include <linux/io.h> +#include <linux/memblock.h> +#include <linux/mm.h> +#include <linux/mman.h> + +#define SHM_ALIGN_MASK (SHMLBA - 1) + +#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(PHYSADDR(kaddr))); +} +EXPORT_SYMBOL_GPL(__virt_addr_valid); + +/* + * You really shouldn't be using read() or write() on /dev/mem. This might go + * away in the future. + */ +int valid_phys_addr_range(phys_addr_t addr, size_t size) +{ + /* + * Check whether addr is covered by a memory region without the + * MEMBLOCK_NOMAP attribute, and whether that region covers the + * entire range. In theory, this could lead to false negatives + * if the range is covered by distinct but adjacent memory regions + * that only differ in other attributes. However, few of such + * attributes have been defined, and it is debatable whether it + * follows that /dev/mem read() calls should be able traverse + * such boundaries. + */ + return memblock_is_region_memory(addr, size) && memblock_is_map_memory(addr); +} + +/* + * Do not allow /dev/mem mappings beyond the supported physical range. + */ +int valid_mmap_phys_addr_range(unsigned long pfn, size_t size) +{ + return !(((pfn << PAGE_SHIFT) + size) & ~(GENMASK_ULL(cpu_pabits, 0))); +} |