diff options
Diffstat (limited to 'arch/arc/mm/mmap.c')
| -rw-r--r-- | arch/arc/mm/mmap.c | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/arch/arc/mm/mmap.c b/arch/arc/mm/mmap.c new file mode 100644 index 000000000..2185afe8d --- /dev/null +++ b/arch/arc/mm/mmap.c @@ -0,0 +1,80 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * ARC700 mmap + * + * (started from arm version - for VIPT alias handling) + * + * Copyright (C) 2013 Synopsys, Inc. (www.synopsys.com) + */ + +#include <linux/fs.h> +#include <linux/mm.h> +#include <linux/mman.h> +#include <linux/sched/mm.h> + +#include <asm/cacheflush.h> + +/* + * Ensure that shared mappings are correctly aligned to + * avoid aliasing issues with VIPT caches. + * We need to ensure that + * a specific page of an object is always mapped at a multiple of + * SHMLBA bytes. + */ +unsigned long +arch_get_unmapped_area(struct file *filp, unsigned long addr, + unsigned long len, unsigned long pgoff, + unsigned long flags, vm_flags_t vm_flags) +{ + struct mm_struct *mm = current->mm; + struct vm_area_struct *vma; + struct vm_unmapped_area_info info = {}; + + /* + * We enforce the MAP_FIXED case. + */ + if (flags & MAP_FIXED) { + if (flags & MAP_SHARED && + (addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)) + return -EINVAL; + return addr; + } + + if (len > TASK_SIZE) + return -ENOMEM; + + if (addr) { + 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.low_limit = mm->mmap_base; + info.high_limit = TASK_SIZE; + info.align_offset = pgoff << PAGE_SHIFT; + return vm_unmapped_area(&info); +} + +static const pgprot_t protection_map[16] = { + [VM_NONE] = PAGE_U_NONE, + [VM_READ] = PAGE_U_R, + [VM_WRITE] = PAGE_U_R, + [VM_WRITE | VM_READ] = PAGE_U_R, + [VM_EXEC] = PAGE_U_X_R, + [VM_EXEC | VM_READ] = PAGE_U_X_R, + [VM_EXEC | VM_WRITE] = PAGE_U_X_R, + [VM_EXEC | VM_WRITE | VM_READ] = PAGE_U_X_R, + [VM_SHARED] = PAGE_U_NONE, + [VM_SHARED | VM_READ] = PAGE_U_R, + [VM_SHARED | VM_WRITE] = PAGE_U_W_R, + [VM_SHARED | VM_WRITE | VM_READ] = PAGE_U_W_R, + [VM_SHARED | VM_EXEC] = PAGE_U_X_R, + [VM_SHARED | VM_EXEC | VM_READ] = PAGE_U_X_R, + [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_U_X_W_R, + [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_U_X_W_R +}; +DECLARE_VM_GET_PAGE_PROT |
