open: yes
close: yes
fault: yes can return with page locked
-map_pages: yes
+map_pages: read
page_mkwrite: yes can return with page locked
pfn_mkwrite: yes
access: yes
->map_pages() is called when VM asks to map easy accessible pages.
Filesystem should find and map pages associated with offsets from "start_pgoff"
-till "end_pgoff". ->map_pages() is called with page table locked and must
+till "end_pgoff". ->map_pages() is called with the RCU lock held and must
not block. If it's not possible to reach a page without blocking,
filesystem should skip it. Filesystem should use do_set_pte() to setup
page table entry. Pointer to entry associated with the page is passed in
/* The page offset of vmf->address within the VMA. */
pgoff_t vma_off = vmf->pgoff - vmf->vma->vm_pgoff;
pgoff_t from_pte, to_pte;
+ vm_fault_t ret;
/* The PTE offset of the start address, clamped to the VMA. */
from_pte = max(ALIGN_DOWN(pte_off, nr_pages),
return VM_FAULT_OOM;
}
- return vmf->vma->vm_ops->map_pages(vmf,
- vmf->pgoff + from_pte - pte_off,
- vmf->pgoff + to_pte - pte_off);
+ rcu_read_lock();
+ ret = vmf->vma->vm_ops->map_pages(vmf,
+ vmf->pgoff + from_pte - pte_off,
+ vmf->pgoff + to_pte - pte_off);
+ rcu_read_unlock();
+
+ return ret;
}
/* Return true if we should do read fault-around, false otherwise */