[PATCH v5 01/27] fs/cachefiles: Remove wait_bit_key layout dependency

[Matthew Wilcox (Oracle)]

Cachefiles was relying on wait_page_key and wait_bit_key being the
same layout, which is fragile.  Now that wait_page_key is exposed in
the pagemap.h header, we can remove that fragility

Signed-off-by: Matthew Wilcox (Oracle) <wi...@infradead.org>
---
 fs/cachefiles/rdwr.c    | 7 +++----
 include/linux/pagemap.h | 1 -
 2 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/fs/cachefiles/rdwr.c b/fs/cachefiles/rdwr.c
index e027c718ca01..8ffc40e84a59 100644
--- a/fs/cachefiles/rdwr.c
+++ b/fs/cachefiles/rdwr.c
@@ -24,17 +24,16 @@ static int cachefiles_read_waiter(wait_queue_entry_t *wait, 
unsigned mode,
                container_of(wait, struct cachefiles_one_read, monitor);
        struct cachefiles_object *object;
        struct fscache_retrieval *op = monitor->op;
-       struct wait_bit_key *key = _key;
+       struct wait_page_key *key = _key;
        struct page *page = wait->private;
 
        ASSERT(key);
 
        _enter("{%lu},%u,%d,{%p,%u}",
               monitor->netfs_page->index, mode, sync,
-              key->flags, key->bit_nr);
+              key->page, key->bit_nr);
 
-       if (key->flags != &page->flags ||
-           key->bit_nr != PG_locked)
+       if (key->page != page || key->bit_nr != PG_locked)
                return 0;
 
        _debug("--- monitor %p %lx ---", page, page->flags);
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index f68fe61c1dec..139678f382ff 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -574,7 +574,6 @@ static inline pgoff_t linear_page_index(struct 
vm_area_struct *vma,
        return pgoff;
 }
 
-/* This has the same layout as wait_bit_key - see fs/cachefiles/rdwr.c */
 struct wait_page_key {
        struct page *page;
        int bit_nr;
-- 
2.30.2