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- jessie 3.16.56-1+deb8u1
VM_INSERT_PAGE(9) | Memory Management in Linux | VM_INSERT_PAGE(9) |
NAME¶
vm_insert_page - insert single page into user vmaSYNOPSIS¶
int
vm_insert_page(struct vm_area_struct * vma,
unsigned long addr,
struct page * page);
ARGUMENTS¶
vmauser vma to map to
addr
target user address of this page
page
source kernel page
DESCRIPTION¶
This allows drivers to insert individual pages they've allocated into a user vma. The page has to be a nice clean _individual_ kernel allocation. If you allocate a compound page, you need to have marked it as such (__GFP_COMP), or manually just split the page up yourself (see split_page). NOTE! Traditionally this was done with " remap_pfn_range" which took an arbitrary page protection parameter. This doesn't allow that. Your vma protection will have to be set up correctly, which means that if you want a shared writable mapping, you'd better ask for a shared writable mapping! The page does not need to be reserved. Usually this function is called from f_op-> mmap handler under mm->mmap_sem write-lock, so it can change vma->vm_flags. Caller must set VM_MIXEDMAP on vma if it wants to call this function from other places, for example from page-fault handler.COPYRIGHT¶
May 2018 | Kernel Hackers Manual 3.16 |