mm: Make default vm_ops provide ->page_mkwrite handler
Make default vm_ops provide ->page_mkwrite handler. Currently it only updates
file's modification times and gets locked page but later it will also handle
filesystem freezing.
BugLink: https://bugs.launchpad.net/bugs/897421
Tested-by: Kamal Mostafa <kamal@canonical.com>
Tested-by: Peter M. Petrakis <peter.petrakis@canonical.com>
Tested-by: Dann Frazier <dann.frazier@canonical.com>
Tested-by: Massimo Morana <massimo.morana@canonical.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/mm/filemap.c b/mm/filemap.c
index a4a5260..51efee6 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1712,8 +1712,27 @@
}
EXPORT_SYMBOL(filemap_fault);
+int filemap_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+ struct page *page = vmf->page;
+ struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
+ int ret = VM_FAULT_LOCKED;
+
+ file_update_time(vma->vm_file);
+ lock_page(page);
+ if (page->mapping != inode->i_mapping) {
+ unlock_page(page);
+ ret = VM_FAULT_NOPAGE;
+ goto out;
+ }
+out:
+ return ret;
+}
+EXPORT_SYMBOL(filemap_page_mkwrite);
+
const struct vm_operations_struct generic_file_vm_ops = {
.fault = filemap_fault,
+ .page_mkwrite = filemap_page_mkwrite,
};
/* This is used for a general mmap of a disk file */
