Merge tag 'folio-5.19' of git://git.infradead.org/users/willy/pagecache

Pull page cache updates from Matthew Wilcox:

 - Appoint myself page cache maintainer

 - Fix how scsicam uses the page cache

 - Use the memalloc_nofs_save() API to replace AOP_FLAG_NOFS

 - Remove the AOP flags entirely

 - Remove pagecache_write_begin() and pagecache_write_end()

 - Documentation updates

 - Convert several address_space operations to use folios:
     - is_dirty_writeback
     - readpage becomes read_folio
     - releasepage becomes release_folio
     - freepage becomes free_folio

 - Change filler_t to require a struct file pointer be the first
   argument like ->read_folio

* tag 'folio-5.19' of git://git.infradead.org/users/willy/pagecache: (107 commits)
  nilfs2: Fix some kernel-doc comments
  Appoint myself page cache maintainer
  fs: Remove aops->freepage
  secretmem: Convert to free_folio
  nfs: Convert to free_folio
  orangefs: Convert to free_folio
  fs: Add free_folio address space operation
  fs: Convert drop_buffers() to use a folio
  fs: Change try_to_free_buffers() to take a folio
  jbd2: Convert release_buffer_page() to use a folio
  jbd2: Convert jbd2_journal_try_to_free_buffers to take a folio
  reiserfs: Convert release_buffer_page() to use a folio
  fs: Remove last vestiges of releasepage
  ubifs: Convert to release_folio
  reiserfs: Convert to release_folio
  orangefs: Convert to release_folio
  ocfs2: Convert to release_folio
  nilfs2: Remove comment about releasepage
  nfs: Convert to release_folio
  jfs: Convert to release_folio
  ...

3 files changed, 41 insertions, 46 deletions

diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c
index 72c9f31ce724..106e90a36583 100644
--- a/fs/gfs2/aops.c
+++ b/fs/gfs2/aops.c
@@ -464,22 +464,26 @@ static int stuffed_readpage(struct gfs2_inode *ip, struct page *page)
 	return 0;
 }
 
-
-static int __gfs2_readpage(void *file, struct page *page)
+/**
+ * gfs2_read_folio - read a folio from a file
+ * @file: The file to read
+ * @folio: The folio in the file
+ */
+static int gfs2_read_folio(struct file *file, struct folio *folio)
 {
-	struct inode *inode = page->mapping->host;
+	struct inode *inode = folio->mapping->host;
 	struct gfs2_inode *ip = GFS2_I(inode);
 	struct gfs2_sbd *sdp = GFS2_SB(inode);
 	int error;
 
 	if (!gfs2_is_jdata(ip) ||
-	    (i_blocksize(inode) == PAGE_SIZE && !page_has_buffers(page))) {
-		error = iomap_readpage(page, &gfs2_iomap_ops);
+	    (i_blocksize(inode) == PAGE_SIZE && !folio_buffers(folio))) {
+		error = iomap_read_folio(folio, &gfs2_iomap_ops);
 	} else if (gfs2_is_stuffed(ip)) {
-		error = stuffed_readpage(ip, page);
-		unlock_page(page);
+		error = stuffed_readpage(ip, &folio->page);
+		folio_unlock(folio);
 	} else {
-		error = mpage_readpage(page, gfs2_block_map);
+		error = mpage_read_folio(folio, gfs2_block_map);
 	}
 
 	if (unlikely(gfs2_withdrawn(sdp)))
@@ -489,17 +493,6 @@ static int __gfs2_readpage(void *file, struct page *page)
 }
 
 /**
- * gfs2_readpage - read a page of a file
- * @file: The file to read
- * @page: The page of the file
- */
-
-static int gfs2_readpage(struct file *file, struct page *page)
-{
-	return __gfs2_readpage(file, page);
-}
-
-/**
  * gfs2_internal_read - read an internal file
  * @ip: The gfs2 inode
  * @buf: The buffer to fill
@@ -523,7 +516,7 @@ int gfs2_internal_read(struct gfs2_inode *ip, char *buf, loff_t *pos,
 		amt = size - copied;
 		if (offset + size > PAGE_SIZE)
 			amt = PAGE_SIZE - offset;
-		page = read_cache_page(mapping, index, __gfs2_readpage, NULL);
+		page = read_cache_page(mapping, index, gfs2_read_folio, NULL);
 		if (IS_ERR(page))
 			return PTR_ERR(page);
 		p = kmap_atomic(page);
@@ -698,38 +691,40 @@ out:
 }
 
 /**
- * gfs2_releasepage - free the metadata associated with a page
- * @page: the page that's being released
+ * gfs2_release_folio - free the metadata associated with a folio
+ * @folio: the folio that's being released
  * @gfp_mask: passed from Linux VFS, ignored by us
  *
- * Calls try_to_free_buffers() to free the buffers and put the page if the
+ * Calls try_to_free_buffers() to free the buffers and put the folio if the
  * buffers can be released.
  *
- * Returns: 1 if the page was put or else 0
+ * Returns: true if the folio was put or else false
  */
 
-int gfs2_releasepage(struct page *page, gfp_t gfp_mask)
+bool gfs2_release_folio(struct folio *folio, gfp_t gfp_mask)
 {
-	struct address_space *mapping = page->mapping;
+	struct address_space *mapping = folio->mapping;
 	struct gfs2_sbd *sdp = gfs2_mapping2sbd(mapping);
 	struct buffer_head *bh, *head;
 	struct gfs2_bufdata *bd;
 
-	if (!page_has_buffers(page))
-		return 0;
+	head = folio_buffers(folio);
+	if (!head)
+		return false;
 
 	/*
-	 * From xfs_vm_releasepage: mm accommodates an old ext3 case where
-	 * clean pages might not have had the dirty bit cleared.  Thus, it can
-	 * send actual dirty pages to ->releasepage() via shrink_active_list().
+	 * mm accommodates an old ext3 case where clean folios might
+	 * not have had the dirty bit cleared.	Thus, it can send actual
+	 * dirty folios to ->release_folio() via shrink_active_list().
 	 *
-	 * As a workaround, we skip pages that contain dirty buffers below.
-	 * Once ->releasepage isn't called on dirty pages anymore, we can warn
-	 * on dirty buffers like we used to here again.
+	 * As a workaround, we skip folios that contain dirty buffers
+	 * below.  Once ->release_folio isn't called on dirty folios
+	 * anymore, we can warn on dirty buffers like we used to here
+	 * again.
 	 */
 
 	gfs2_log_lock(sdp);
-	head = bh = page_buffers(page);
+	bh = head;
 	do {
 		if (atomic_read(&bh->b_count))
 			goto cannot_release;
@@ -739,9 +734,9 @@ int gfs2_releasepage(struct page *page, gfp_t gfp_mask)
 		if (buffer_dirty(bh) || WARN_ON(buffer_pinned(bh)))
 			goto cannot_release;
 		bh = bh->b_this_page;
-	} while(bh != head);
+	} while (bh != head);
 
-	head = bh = page_buffers(page);
+	bh = head;
 	do {
 		bd = bh->b_private;
 		if (bd) {
@@ -762,20 +757,20 @@ int gfs2_releasepage(struct page *page, gfp_t gfp_mask)
 	} while (bh != head);
 	gfs2_log_unlock(sdp);
 
-	return try_to_free_buffers(page);
+	return try_to_free_buffers(folio);
 
 cannot_release:
 	gfs2_log_unlock(sdp);
-	return 0;
+	return false;
 }
 
 static const struct address_space_operations gfs2_aops = {
 	.writepage = gfs2_writepage,
 	.writepages = gfs2_writepages,
-	.readpage = gfs2_readpage,
+	.read_folio = gfs2_read_folio,
 	.readahead = gfs2_readahead,
 	.dirty_folio = filemap_dirty_folio,
-	.releasepage = iomap_releasepage,
+	.release_folio = iomap_release_folio,
 	.invalidate_folio = iomap_invalidate_folio,
 	.bmap = gfs2_bmap,
 	.direct_IO = noop_direct_IO,
@@ -787,12 +782,12 @@ static const struct address_space_operations gfs2_aops = {
 static const struct address_space_operations gfs2_jdata_aops = {
 	.writepage = gfs2_jdata_writepage,
 	.writepages = gfs2_jdata_writepages,
-	.readpage = gfs2_readpage,
+	.read_folio = gfs2_read_folio,
 	.readahead = gfs2_readahead,
 	.dirty_folio = jdata_dirty_folio,
 	.bmap = gfs2_bmap,
 	.invalidate_folio = gfs2_invalidate_folio,
-	.releasepage = gfs2_releasepage,
+	.release_folio = gfs2_release_folio,
 	.is_partially_uptodate = block_is_partially_uptodate,
 	.error_remove_page = generic_error_remove_page,
 };
diff --git a/fs/gfs2/inode.h b/fs/gfs2/inode.h
index 7b2c1f390db7..0264d514dda7 100644
--- a/fs/gfs2/inode.h
+++ b/fs/gfs2/inode.h
@@ -12,7 +12,7 @@
 #include <linux/mm.h>
 #include "util.h"
 
-extern int gfs2_releasepage(struct page *page, gfp_t gfp_mask);
+bool gfs2_release_folio(struct folio *folio, gfp_t gfp_mask);
 extern int gfs2_internal_read(struct gfs2_inode *ip,
 			      char *buf, loff_t *pos, unsigned size);
 extern void gfs2_set_aops(struct inode *inode);
diff --git a/fs/gfs2/meta_io.c b/fs/gfs2/meta_io.c
index d8bd1d48bd78..868dcc71b581 100644
--- a/fs/gfs2/meta_io.c
+++ b/fs/gfs2/meta_io.c
@@ -92,14 +92,14 @@ const struct address_space_operations gfs2_meta_aops = {
 	.dirty_folio	= block_dirty_folio,
 	.invalidate_folio = block_invalidate_folio,
 	.writepage = gfs2_aspace_writepage,
-	.releasepage = gfs2_releasepage,
+	.release_folio = gfs2_release_folio,
 };
 
 const struct address_space_operations gfs2_rgrp_aops = {
 	.dirty_folio	= block_dirty_folio,
 	.invalidate_folio = block_invalidate_folio,
 	.writepage = gfs2_aspace_writepage,
-	.releasepage = gfs2_releasepage,
+	.release_folio = gfs2_release_folio,
 };
 
 /**