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remap_pfn_range(9) [centos man page]

REMAP_PFN_RANGE(9)					    Memory Management in Linux						REMAP_PFN_RANGE(9)

NAME
remap_pfn_range - remap kernel memory to userspace SYNOPSIS
int remap_pfn_range(struct vm_area_struct * vma, unsigned long addr, unsigned long pfn, unsigned long size, pgprot_t prot); ARGUMENTS
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 NOTE
this is only safe if the mm semaphore is held when called. COPYRIGHT
Kernel Hackers Manual 3.10 June 2014 REMAP_PFN_RANGE(9)

Check Out this Related Man Page

mprotect(2)							System Calls Manual						       mprotect(2)

NAME
mprotect() - set or check protection of memory mapping SYNOPSIS
DESCRIPTION
The function changes the access protections on the mappings specified by the range [addr, addr+len], rounding len up to the next multiple of the page size as returned by to be that specified by prot. Legitimate values for prot are the same as those permitted for and are defined in Page can be read. Page can be written. Page can be executed. Page cannot be accessed. Check page effective permissions If flag is specified, checks the access protections on the mappings specified with the rest of prot value to see if the requested permis- sions are set. If the address range being modified corresponds to a mapped file that was mapped with grants write access permission only if the file descriptor used to map the file was opened for writing. If the address range corresponds to a mapped file that was mapped with the or the flag, grants all requested access permissions. When fails for reasons other than the protections on some of the pages in the range [addr, addr+len] may have been changed. For example, if an error occurs on some page at an addr2, then may have modified the protections of all whole pages in the range [addr,addr2]. RETURN VALUE
Upon successful completion, returns Otherwise, it returns and sets to indicate the error. ERRORS
The function will fail if: The prot argument specifies a protection that violates, or is different than (in the case where flag is present), the access permission the process has to the underlying memory object. prot is invalid, or addr is not a multiple of the page size as returned by The range specified by [addr, addr+len] (from, and including, addr to, but not including, addr+len) is invalid for the address space of a process, or the range specifies one or more unmapped pages. Addresses in the range [addr, addr+len] are invalid for the address space of a process, or specify one or more pages which are not mapped. The prot argument specifies over a mapping and there are insufficient memory resources to reserve for locking the private page. AUTHOR
was developed by HP, AT&T, and OSF. SEE ALSO
mmap(2), sysconf(2), <sys/mman.h>. STANDARDS CONFORMANCE
mprotect(2)

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