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csky: Fixup arch_get_unmapped_area() implementation

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Current arch_get_unmapped_area() of abiv1 doesn't use standard kernel
api. After referring to the implementation of arch/arm, we implement
it with vm_unmapped_area() from linux/mm.h.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>
This commit is contained in:
Guo Ren 2019-08-20 15:31:29 +08:00
parent 5336c17928
commit be819aa6f1
2 changed files with 44 additions and 38 deletions
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5
arch/csky/abiv1/inc/abi/page.h
View File

@ -1,13 +1,14 @@
/* SPDX-License-Identifier: GPL-2.0 */
// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
extern unsigned long shm_align_mask;
#include <asm/shmparam.h>
extern void flush_dcache_page(struct page *page);
static inline unsigned long pages_do_alias(unsigned long addr1,
unsigned long addr2)
{
return (addr1 ^ addr2) & shm_align_mask;
return (addr1 ^ addr2) & (SHMLBA-1);
}
static inline void clear_user_page(void *addr, unsigned long vaddr,

77
arch/csky/abiv1/mmap.c
View File

@ -9,58 +9,63 @@
#include <linux/random.h>
#include <linux/io.h>
unsigned long shm_align_mask = (0x4000 >> 1) - 1; /* Sane caches */
#define COLOUR_ALIGN(addr,pgoff) \
((((addr)+SHMLBA-1)&~(SHMLBA-1)) + \
(((pgoff)<<PAGE_SHIFT) & (SHMLBA-1)))
#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,
/*
* We need to 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.
*
* We unconditionally provide this function for all cases.
*/
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;
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
int do_align = 0;
struct vm_unmapped_area_info info;
/*
* We only need to do colour alignment if either the I or D
* caches alias.
*/
do_align = filp || (flags & MAP_SHARED);
/*
* We enforce the MAP_FIXED case.
*/
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))
if (flags & MAP_SHARED &&
(addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1))
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)
if (do_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)
vma = find_vma(mm, addr);
if (TASK_SIZE - len >= addr &&
(!vma || addr + len <= vm_start_gap(vma)))
return addr;
addr = vmm->vm_end;
if (do_color_align)
addr = COLOUR_ALIGN(addr, pgoff);
}
info.flags = 0;
info.length = len;
info.low_limit = mm->mmap_base;
info.high_limit = TASK_SIZE;
info.align_mask = do_align ? (PAGE_MASK & (SHMLBA - 1)) : 0;
info.align_offset = pgoff << PAGE_SHIFT;
return vm_unmapped_area(&info);
}