mm: Remove the PG_fscache alias for PG_private_2

Remove the PG_fscache alias for PG_private_2 and use the latter directly.
Use of this flag for marking pages undergoing writing to the cache should
be considered deprecated and the folios should be marked dirty instead and
the write done in ->writepages().

Note that PG_private_2 itself should be considered deprecated and up for
future removal by the MM folks too.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
cc: Matthew Wilcox (Oracle) <willy@infradead.org>
cc: Ilya Dryomov <idryomov@gmail.com>
cc: Xiubo Li <xiubli@redhat.com>
cc: Steve French <sfrench@samba.org>
cc: Paulo Alcantara <pc@manguebit.com>
cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
cc: Shyam Prasad N <sprasad@microsoft.com>
cc: Tom Talpey <tom@talpey.com>
cc: Bharath SM <bharathsm@microsoft.com>
cc: Trond Myklebust <trond.myklebust@hammerspace.com>
cc: Anna Schumaker <anna@kernel.org>
cc: netfs@lists.linux.dev
cc: ceph-devel@vger.kernel.org
cc: linux-cifs@vger.kernel.org
cc: linux-nfs@vger.kernel.org
cc: linux-fsdevel@vger.kernel.org
cc: linux-mm@kvack.org

1 files changed, 4 insertions, 76 deletions

diff --git a/include/linux/netfs.h b/include/linux/netfs.h
index f5e9c5f84a0c..f36a6d8163d1 100644
--- a/include/linux/netfs.h
+++ b/include/linux/netfs.h
@@ -21,94 +21,22 @@
 
 enum netfs_sreq_ref_trace;
 
-/*
- * Overload PG_private_2 to give us PG_fscache - this is used to indicate that
- * a page is currently backed by a local disk cache
- */
-#define folio_test_fscache(folio)	folio_test_private_2(folio)
-#define PageFsCache(page)		PagePrivate2((page))
-#define SetPageFsCache(page)		SetPagePrivate2((page))
-#define ClearPageFsCache(page)		ClearPagePrivate2((page))
-#define TestSetPageFsCache(page)	TestSetPagePrivate2((page))
-#define TestClearPageFsCache(page)	TestClearPagePrivate2((page))
-
 /**
- * folio_start_fscache - Start an fscache write on a folio.
+ * folio_start_private_2 - Start an fscache write on a folio.  [DEPRECATED]
  * @folio: The folio.
  *
  * Call this function before writing a folio to a local cache.  Starting a
  * second write before the first one finishes is not allowed.
+ *
+ * Note that this should no longer be used.
  */
-static inline void folio_start_fscache(struct folio *folio)
+static inline void folio_start_private_2(struct folio *folio)
 {
 	VM_BUG_ON_FOLIO(folio_test_private_2(folio), folio);
 	folio_get(folio);
 	folio_set_private_2(folio);
 }
 
-/**
- * folio_end_fscache - End an fscache write on a folio.
- * @folio: The folio.
- *
- * Call this function after the folio has been written to the local cache.
- * This will wake any sleepers waiting on this folio.
- */
-static inline void folio_end_fscache(struct folio *folio)
-{
-	folio_end_private_2(folio);
-}
-
-/**
- * folio_wait_fscache - Wait for an fscache write on this folio to end.
- * @folio: The folio.
- *
- * If this folio is currently being written to a local cache, wait for
- * the write to finish.  Another write may start after this one finishes,
- * unless the caller holds the folio lock.
- */
-static inline void folio_wait_fscache(struct folio *folio)
-{
-	folio_wait_private_2(folio);
-}
-
-/**
- * folio_wait_fscache_killable - Wait for an fscache write on this folio to end.
- * @folio: The folio.
- *
- * If this folio is currently being written to a local cache, wait
- * for the write to finish or for a fatal signal to be received.
- * Another write may start after this one finishes, unless the caller
- * holds the folio lock.
- *
- * Return:
- * - 0 if successful.
- * - -EINTR if a fatal signal was encountered.
- */
-static inline int folio_wait_fscache_killable(struct folio *folio)
-{
-	return folio_wait_private_2_killable(folio);
-}
-
-static inline void set_page_fscache(struct page *page)
-{
-	folio_start_fscache(page_folio(page));
-}
-
-static inline void end_page_fscache(struct page *page)
-{
-	folio_end_private_2(page_folio(page));
-}
-
-static inline void wait_on_page_fscache(struct page *page)
-{
-	folio_wait_private_2(page_folio(page));
-}
-
-static inline int wait_on_page_fscache_killable(struct page *page)
-{
-	return folio_wait_private_2_killable(page_folio(page));
-}
-
 /* Marks used on xarray-based buffers */
 #define NETFS_BUF_PUT_MARK	XA_MARK_0	/* - Page needs putting  */
 #define NETFS_BUF_PAGECACHE_MARK XA_MARK_1	/* - Page needs wb/dirty flag wrangling */