1 files changed, 31 insertions, 60 deletions

diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 3e248d1c3969..757bc4d3b5b5 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -38,10 +38,10 @@
 #include <linux/sched/rt.h>
 #include <linux/sched/signal.h>
 #include <linux/mm_inline.h>
+#include <linux/shmem_fs.h>
 #include <trace/events/writeback.h>
 
 #include "internal.h"
-#include "swap.h"
 
 /*
  * Sleep at most 200ms at a time in balance_dirty_pages().
@@ -2590,36 +2590,6 @@ done:
 }
 EXPORT_SYMBOL_GPL(writeback_iter);
 
-/**
- * write_cache_pages - walk the list of dirty pages of the given address space and write all of them.
- * @mapping: address space structure to write
- * @wbc: subtract the number of written pages from *@wbc->nr_to_write
- * @writepage: function called for each page
- * @data: data passed to writepage function
- *
- * Return: %0 on success, negative error code otherwise
- *
- * Note: please use writeback_iter() instead.
- */
-int write_cache_pages(struct address_space *mapping,
-		      struct writeback_control *wbc, writepage_t writepage,
-		      void *data)
-{
-	struct folio *folio = NULL;
-	int error;
-
-	while ((folio = writeback_iter(mapping, wbc, folio, &error))) {
-		error = writepage(folio, wbc, data);
-		if (error == AOP_WRITEPAGE_ACTIVATE) {
-			folio_unlock(folio);
-			error = 0;
-		}
-	}
-
-	return error;
-}
-EXPORT_SYMBOL(write_cache_pages);
-
 int do_writepages(struct address_space *mapping, struct writeback_control *wbc)
 {
 	int ret;
@@ -2735,12 +2705,18 @@ void __folio_mark_dirty(struct folio *folio, struct address_space *mapping,
 {
 	unsigned long flags;
 
+	/*
+	 * Shmem writeback relies on swap, and swap writeback is LRU based,
+	 * not using the dirty mark.
+	 */
+	VM_WARN_ON_ONCE(folio_test_swapcache(folio) || shmem_mapping(mapping));
+
 	xa_lock_irqsave(&mapping->i_pages, flags);
 	if (folio->mapping) {	/* Race with truncate? */
 		WARN_ON_ONCE(warn && !folio_test_uptodate(folio));
 		folio_account_dirtied(folio, mapping);
-		__xa_set_mark(&mapping->i_pages, folio_index(folio),
-				PAGECACHE_TAG_DIRTY);
+		__xa_set_mark(&mapping->i_pages, folio->index,
+			      PAGECACHE_TAG_DIRTY);
 	}
 	xa_unlock_irqrestore(&mapping->i_pages, flags);
 }
@@ -3014,26 +2990,23 @@ bool __folio_end_writeback(struct folio *folio)
 
 	if (mapping && mapping_use_writeback_tags(mapping)) {
 		struct inode *inode = mapping->host;
-		struct backing_dev_info *bdi = inode_to_bdi(inode);
+		struct bdi_writeback *wb;
 		unsigned long flags;
 
 		xa_lock_irqsave(&mapping->i_pages, flags);
 		ret = folio_xor_flags_has_waiters(folio, 1 << PG_writeback);
-		__xa_clear_mark(&mapping->i_pages, folio_index(folio),
+		__xa_clear_mark(&mapping->i_pages, folio->index,
 					PAGECACHE_TAG_WRITEBACK);
-		if (bdi->capabilities & BDI_CAP_WRITEBACK_ACCT) {
-			struct bdi_writeback *wb = inode_to_wb(inode);
 
-			wb_stat_mod(wb, WB_WRITEBACK, -nr);
-			__wb_writeout_add(wb, nr);
-			if (!mapping_tagged(mapping, PAGECACHE_TAG_WRITEBACK))
-				wb_inode_writeback_end(wb);
+		wb = inode_to_wb(inode);
+		wb_stat_mod(wb, WB_WRITEBACK, -nr);
+		__wb_writeout_add(wb, nr);
+		if (!mapping_tagged(mapping, PAGECACHE_TAG_WRITEBACK)) {
+			wb_inode_writeback_end(wb);
+			if (mapping->host)
+				sb_clear_inode_writeback(mapping->host);
 		}
 
-		if (mapping->host && !mapping_tagged(mapping,
-						     PAGECACHE_TAG_WRITEBACK))
-			sb_clear_inode_writeback(mapping->host);
-
 		xa_unlock_irqrestore(&mapping->i_pages, flags);
 	} else {
 		ret = folio_xor_flags_has_waiters(folio, 1 << PG_writeback);
@@ -3056,9 +3029,9 @@ void __folio_start_writeback(struct folio *folio, bool keep_write)
 	VM_BUG_ON_FOLIO(!folio_test_locked(folio), folio);
 
 	if (mapping && mapping_use_writeback_tags(mapping)) {
-		XA_STATE(xas, &mapping->i_pages, folio_index(folio));
+		XA_STATE(xas, &mapping->i_pages, folio->index);
 		struct inode *inode = mapping->host;
-		struct backing_dev_info *bdi = inode_to_bdi(inode);
+		struct bdi_writeback *wb;
 		unsigned long flags;
 		bool on_wblist;
 
@@ -3069,21 +3042,19 @@ void __folio_start_writeback(struct folio *folio, bool keep_write)
 		on_wblist = mapping_tagged(mapping, PAGECACHE_TAG_WRITEBACK);
 
 		xas_set_mark(&xas, PAGECACHE_TAG_WRITEBACK);
-		if (bdi->capabilities & BDI_CAP_WRITEBACK_ACCT) {
-			struct bdi_writeback *wb = inode_to_wb(inode);
-
-			wb_stat_mod(wb, WB_WRITEBACK, nr);
-			if (!on_wblist)
-				wb_inode_writeback_start(wb);
+		wb = inode_to_wb(inode);
+		wb_stat_mod(wb, WB_WRITEBACK, nr);
+		if (!on_wblist) {
+			wb_inode_writeback_start(wb);
+			/*
+			 * We can come through here when swapping anonymous
+			 * folios, so we don't necessarily have an inode to
+			 * track for sync.
+			 */
+			if (mapping->host)
+				sb_mark_inode_writeback(mapping->host);
 		}
 
-		/*
-		 * We can come through here when swapping anonymous
-		 * folios, so we don't necessarily have an inode to
-		 * track for sync.
-		 */
-		if (mapping->host && !on_wblist)
-			sb_mark_inode_writeback(mapping->host);
 		if (!folio_test_dirty(folio))
 			xas_clear_mark(&xas, PAGECACHE_TAG_DIRTY);
 		if (!keep_write)