filemap_fault (9) - Linux Manuals

filemap_fault: read in file data for page fault handling

Command to display filemap_fault manual in Linux: $ man 9 filemap_fault

NAME

filemap_fault - read in file data for page fault handling

SYNOPSIS

int filemap_fault(struct vm_area_struct * vma, struct vm_fault * vmf);

ARGUMENTS

vma

: vma in which the fault was taken

vmf

: struct vm_fault containing details of the fault

DESCRIPTION

filemap_fault is invoked via the vma operations vector for a mapped memory region to read in file data during a page fault.

The goto's are kind of ugly, but this streamlines the normal case of having it in the page cache, and handles the special cases reasonably without having a lot of duplicated code.

vma->vm_mm->mmap_sem must be held on entry.

If our return value has VM_FAULT_RETRY set, it's because lock_page_or_retry returned 0. The mmap_sem has usually been released in this case. See __lock_page_or_retry for the exception.

If our return value does not have VM_FAULT_RETRY set, the mmap_sem has not been released.

We never return with VM_FAULT_RETRY and a bit from VM_FAULT_ERROR set.