| Message ID | 20210320054104.1300774-2-willy@infradead.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Memory Folios | expand |
On Sat, Mar 20, 2021 at 05:40:38AM +0000, Matthew Wilcox (Oracle) wrote: > 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) <willy@infradead.org> Looks good, Reviewed-by: Christoph Hellwig <hch@lst.de>
Matthew Wilcox (Oracle) <willy@infradead.org> wrote: > 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) <willy@infradead.org> Acked-and-tested-by: David Howells <dhowells@redhat.com> I wonder if this could be pushed directly to Linus now since we're relying on two different structs being compatible.
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;
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) <willy@infradead.org> --- fs/cachefiles/rdwr.c | 7 +++---- include/linux/pagemap.h | 1 - 2 files changed, 3 insertions(+), 5 deletions(-)