remap_pfn

函数名称：map_pfn_range - remap kernel memory to userspace*@vma: user vma to map to*@addr: target user address to start at*@pfn: physical address of kernel memory*@size: size of map area*@prot: page protection flags for this mapping

函数原型：int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn, unsigned long size, pgprot_t prot)

返回类型：int

参数：

类型	参数	名称
struct vm_area_struct *	vma
unsigned long	addr
unsigned long	pfn
unsigned long	size
pgprot_t	prot

1919

end等于addr加 align the pointer to the (next) page boundary (size)

1920

mm等于The address space we belong to.

1921

remap_pfn等于pfn

1942

如果is_cow_mapping(Flags, see mm.h. )则

1943

如果addr不等于Our start address within vm_mm. 或end不等于The first byte after our end addresswithin vm_mm. 则返回:负EINVAL

1945

Offset (within vm_file) in PAGE_SIZEunits 等于pfn

1948

err等于track_pfn_remap(vma, & prot, remap_pfn, addr, align the pointer to the (next) page boundary (size))

1949

如果err则返回:负EINVAL

1952

Flags, see mm.h. 或等于Memory mapped I/O or similar 按位或Page-ranges managed without "struct page", just pure PFN 按位或Cannot expand with mremap() 按位或Do not include in the core dump

1954

BUG_ON(addr >= end)

1955

pfn减等于addr右移PAGE_SHIFT determines the page size 位

1956

pgd等于a shortcut to get a pgd_t in a given mm(mm, addr)

1957

flush_cache_range(vma, addr, end)

1958

循环

1959

next等于When walking page tables, get the address of the next boundary,* or the end address of the range if that comes earlier. Although no* vma end wraps to 0, rounded up __boundary may wrap to 0 throughout.(addr, end)

1960

err等于remap_p4d_range(mm, pgd, addr, next, pfn + (addr >> PAGE_SHIFT determines the page size ), prot)

1962

如果err则退出

1964

当pgd自加, addr等于next, addr不等于end 循环

1966

如果err则untrack_pfn(vma, remap_pfn, align the pointer to the (next) page boundary (size))

1969

返回:err

**调用者**
名称	描述
dma_direct_mmap
__dma_mmap_from_coherent

源代码转换工具开放的插件接口	X
支持：c/c++/esqlc/java Oracle/Informix/Mysql 插件可实现：逻辑报告代码生成和批量转换代码

函数逻辑报告