VM_MAP_RAM(9) Memory Management in Linux VM_MAP_RAM(9)NAME
vm_map_ram - map pages linearly into kernel virtual address (vmalloc space)
void * vm_map_ram(struct page ** pages, unsigned int count, int node, pgprot_t prot);
an array of pointers to the pages to be mapped
number of pages
prefer to allocate data structures on this node
memory protection to use. PAGE_KERNEL for regular RAM
a pointer to the address that has been mapped, or NULL on failure
COPYRIGHT Kernel Hackers Manual 3.10 June 2014 VM_MAP_RAM(9)
Check Out this Related Man Page
mvalid(2) System Calls Manual mvalid(2)NAME
mvalid() - check memory region for validity
addr The address of the region whose validity is to be checked.
len The length in bytes of the region specified by the addr parameter.
prot The desired access protection for the region.
The function checks the validity of a memory region. A region is considered to be valid if accesses of the requested type are allowed to
all addresses in the region.
The header file defines the following access options:
The mapped region can be read.
The mapped region can be written.
The mapped region can be executed.
The prot parameter can be any combination of and ORed together.
The function returns:
Accesses requiring the specified protection are allowed to all addresses within the specified range of addresses.
is set to indicate the error.
If the function fails, may be set to one of the following values:
The range specified by
(addr, addr+len) is invalid for the process's address space, or the range specifies one or more unmapped pages, or one or
more pages of the range disallows accesses of the specified protection.
The prot parameter is invalid, or the addr parameter is not a multiple of the page size as returned by
The range specified by
(addr, addr+len) is invalid for the process's address space, or the range specifies one or more unmapped pages.
was developed by HP.
SEE ALSO mmap(2), mprotect(2), sysconf(2).
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