UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

csky: Fixup dma_alloc_coherent with PAGE_SO attribute 

This bug is from commit: 2b070ccdf8 (fixup abiv2 mmap(... O_SYNC)
failed). In that patch we remove the _PAGE_SO for memory noncache
mapping and this will cause problem when drivers use dma descriptors
to control the transcations without dma_w/rmb().

After referencing other archs' implementation, pgprot_writecombine is
introduced for mmap(... O_SYNC).

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
This commit is contained in:
Guo Ren 2019-07-30 14:43:22 +08:00
parent 81b23ba645
commit 7f80fe207d
2 changed files with 12 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
arch/csky/include/asm/pgtable.h
View File

@ -258,6 +258,16 @@ static inline pgprot_t pgprot_noncached(pgprot_t _prot)
{
unsigned long prot = pgprot_val(_prot);
prot = (prot & ~_CACHE_MASK) | _CACHE_UNCACHED | _PAGE_SO;
return __pgprot(prot);
}
#define pgprot_writecombine pgprot_writecombine
static inline pgprot_t pgprot_writecombine(pgprot_t _prot)
{
unsigned long prot = pgprot_val(_prot);
prot = (prot & ~_CACHE_MASK) | _CACHE_UNCACHED;
return __pgprot(prot);

6
arch/csky/mm/ioremap.c
View File

@ -29,8 +29,7 @@ void __iomem *ioremap(phys_addr_t addr, size_t size)
vaddr = (unsigned long)area->addr;
prot = __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE |
_PAGE_GLOBAL | _CACHE_UNCACHED | _PAGE_SO);
prot = pgprot_noncached(PAGE_KERNEL);
if (ioremap_page_range(vaddr, vaddr + size, addr, prot)) {
free_vm_area(area);
@ -51,10 +50,9 @@ pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
unsigned long size, pgprot_t vma_prot)
{
if (!pfn_valid(pfn)) {
vma_prot.pgprot |= _PAGE_SO;
return pgprot_noncached(vma_prot);
} else if (file->f_flags & O_SYNC) {
return pgprot_noncached(vma_prot);
return pgprot_writecombine(vma_prot);
}
return vma_prot;