ceph: convert ceph_writepages_start() to use filemap_get_folios_tag()

Convert function to use a folio_batch instead of pagevec.  This is in
preparation for the removal of find_get_pages_range_tag().

Also some minor renaming for consistency.

Link: https://lkml.kernel.org/r/20230104211448.4804-9-vishal.moola@gmail.comSigned-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

fs/ceph/addr.c

@@ -792,7 +792,7 @@ static int ceph_writepages_start(struct address_space *mapping,
 	struct ceph_vino vino = ceph_vino(inode);
 	pgoff_t index, start_index, end = -1;
 	struct ceph_snap_context *snapc = NULL, *last_snapc = NULL, *pgsnapc;
-	struct pagevec pvec;
+	struct folio_batch fbatch;
 	int rc = 0;
 	unsigned int wsize = i_blocksize(inode);
 	struct ceph_osd_request *req = NULL;
@@ -821,7 +821,7 @@ static int ceph_writepages_start(struct address_space *mapping,
 	if (fsc->mount_options->wsize < wsize)
 		wsize = fsc->mount_options->wsize;
 
-	pagevec_init(&pvec);
+	folio_batch_init(&fbatch);
 
 	start_index = wbc->range_cyclic ? mapping->writeback_index : 0;
 	index = start_index;
@@ -869,7 +869,7 @@ static int ceph_writepages_start(struct address_space *mapping,
 
 	while (!done && index <= end) {
 		int num_ops = 0, op_idx;
-		unsigned i, pvec_pages, max_pages, locked_pages = 0;
+		unsigned i, nr_folios, max_pages, locked_pages = 0;
 		struct page **pages = NULL, **data_pages;
 		struct page *page;
 		pgoff_t strip_unit_end = 0;
@@ -879,13 +879,13 @@ static int ceph_writepages_start(struct address_space *mapping,
 		max_pages = wsize >> PAGE_SHIFT;
 
 get_more_pages:
-		pvec_pages = pagevec_lookup_range_tag(&pvec, mapping, &index,
-						end, PAGECACHE_TAG_DIRTY);
-		dout("pagevec_lookup_range_tag got %d\n", pvec_pages);
-		if (!pvec_pages && !locked_pages)
+		nr_folios = filemap_get_folios_tag(mapping, &index,
+				end, PAGECACHE_TAG_DIRTY, &fbatch);
+		dout("pagevec_lookup_range_tag got %d\n", nr_folios);
+		if (!nr_folios && !locked_pages)
 			break;
-		for (i = 0; i < pvec_pages && locked_pages < max_pages; i++) {
-			page = pvec.pages[i];
+		for (i = 0; i < nr_folios && locked_pages < max_pages; i++) {
+			page = &fbatch.folios[i]->page;
 			dout("? %p idx %lu\n", page, page->index);
 			if (locked_pages == 0)
 				lock_page(page);  /* first page */
@@ -995,7 +995,7 @@ static int ceph_writepages_start(struct address_space *mapping,
 				len = 0;
 			}
 
-			/* note position of first page in pvec */
+			/* note position of first page in fbatch */
 			dout("%p will write page %p idx %lu\n",
 			     inode, page, page->index);
 
@@ -1005,30 +1005,30 @@ static int ceph_writepages_start(struct address_space *mapping,
 				fsc->write_congested = true;
 
 			pages[locked_pages++] = page;
-			pvec.pages[i] = NULL;
+			fbatch.folios[i] = NULL;
 
 			len += thp_size(page);
 		}
 
 		/* did we get anything? */
 		if (!locked_pages)
-			goto release_pvec_pages;
+			goto release_folios;
 		if (i) {
 			unsigned j, n = 0;
-			/* shift unused page to beginning of pvec */
-			for (j = 0; j < pvec_pages; j++) {
-				if (!pvec.pages[j])
+			/* shift unused page to beginning of fbatch */
+			for (j = 0; j < nr_folios; j++) {
+				if (!fbatch.folios[j])
 					continue;
 				if (n < j)
-					pvec.pages[n] = pvec.pages[j];
+					fbatch.folios[n] = fbatch.folios[j];
 				n++;
 			}
-			pvec.nr = n;
+			fbatch.nr = n;
 
-			if (pvec_pages && i == pvec_pages &&
+			if (nr_folios && i == nr_folios &&
 			    locked_pages < max_pages) {
-				dout("reached end pvec, trying for more\n");
-				pagevec_release(&pvec);
+				dout("reached end fbatch, trying for more\n");
+				folio_batch_release(&fbatch);
 				goto get_more_pages;
 			}
 		}
@@ -1164,10 +1164,10 @@ static int ceph_writepages_start(struct address_space *mapping,
 		if (wbc->nr_to_write <= 0 && wbc->sync_mode == WB_SYNC_NONE)
 			done = true;
 
-release_pvec_pages:
-		dout("pagevec_release on %d pages (%p)\n", (int)pvec.nr,
-		     pvec.nr ? pvec.pages[0] : NULL);
-		pagevec_release(&pvec);
+release_folios:
+		dout("folio_batch release on %d folios (%p)\n", (int)fbatch.nr,
+		     fbatch.nr ? fbatch.folios[0] : NULL);
+		folio_batch_release(&fbatch);
 	}
 
 	if (should_loop && !done) {
@@ -1184,15 +1184,17 @@ static int ceph_writepages_start(struct address_space *mapping,
 			unsigned i, nr;
 			index = 0;
 			while ((index <= end) &&
-			       (nr = pagevec_lookup_tag(&pvec, mapping, &index,
-						PAGECACHE_TAG_WRITEBACK))) {
+			       (nr = filemap_get_folios_tag(mapping, &index,
+						(pgoff_t)-1,
+						PAGECACHE_TAG_WRITEBACK,
+						&fbatch))) {
 				for (i = 0; i < nr; i++) {
-					page = pvec.pages[i];
+					page = &fbatch.folios[i]->page;
 					if (page_snap_context(page) != snapc)
 						continue;
 					wait_on_page_writeback(page);
 				}
-				pagevec_release(&pvec);
+				folio_batch_release(&fbatch);
 				cond_resched();
 			}
 		}