NFS: Add comment banners to some NFS functions

Add comment banners to some NFS functions so that they can be modified by the
NFS fscache patches for further information.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Daire Byrne <Daire.Byrne@framestore.com>
This commit is contained in:
David Howells 2009-04-03 16:42:41 +01:00
parent 9b3f26c911
commit 6b9b3514aa

View file

@ -409,6 +409,13 @@ static int nfs_write_end(struct file *file, struct address_space *mapping,
return copied;
}
/*
* Partially or wholly invalidate a page
* - Release the private state associated with a page if undergoing complete
* page invalidation
* - Called if either PG_private or PG_private_2 is set on the page
* - Caller holds page lock
*/
static void nfs_invalidate_page(struct page *page, unsigned long offset)
{
dfprintk(PAGECACHE, "NFS: invalidate_page(%p, %lu)\n", page, offset);
@ -419,6 +426,12 @@ static void nfs_invalidate_page(struct page *page, unsigned long offset)
nfs_wb_page_cancel(page->mapping->host, page);
}
/*
* Attempt to release the private state associated with a page
* - Called if either PG_private or PG_private_2 is set on the page
* - Caller holds page lock
* - Return true (may release page) or false (may not)
*/
static int nfs_release_page(struct page *page, gfp_t gfp)
{
dfprintk(PAGECACHE, "NFS: release_page(%p)\n", page);
@ -427,6 +440,14 @@ static int nfs_release_page(struct page *page, gfp_t gfp)
return 0;
}
/*
* Attempt to clear the private state associated with a page when an error
* occurs that requires the cached contents of an inode to be written back or
* destroyed
* - Called if either PG_private or PG_private_2 is set on the page
* - Caller holds page lock
* - Return 0 if successful, -error otherwise
*/
static int nfs_launder_page(struct page *page)
{
struct inode *inode = page->mapping->host;
@ -451,6 +472,11 @@ const struct address_space_operations nfs_file_aops = {
.launder_page = nfs_launder_page,
};
/*
* Notification that a PTE pointing to an NFS page is about to be made
* writable, implying that someone is about to modify the page through a
* shared-writable mapping
*/
static int nfs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
{
struct page *page = vmf->page;