+ nilfs2-return-the-mapped-address-from-nilfs_get_page.patch added to mm-nonmm-unstable branch

[Andrew Morton <akpm@linux-foundation.org>]

The patch titled
     Subject: nilfs2: return the mapped address from nilfs_get_page()
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     nilfs2-return-the-mapped-address-from-nilfs_get_page.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/nilfs2-return-the-mapped-address-from-nilfs_get_page.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Subject: nilfs2: return the mapped address from nilfs_get_page()
Date: Mon, 27 Nov 2023 23:30:25 +0900

In prepartion for switching from kmap() to kmap_local(), return the kmap
address from nilfs_get_page() instead of having the caller look up
page_address().

[konishi.ryusuke: fixed a missing blank line after declaration]
Link: https://lkml.kernel.org/r/20231127143036.2425-7-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/nilfs2/dir.c |   57 +++++++++++++++++++++-------------------------
 1 file changed, 27 insertions(+), 30 deletions(-)

--- a/fs/nilfs2/dir.c~nilfs2-return-the-mapped-address-from-nilfs_get_page
+++ a/fs/nilfs2/dir.c
@@ -180,19 +180,24 @@ fail:
 	return false;
 }
 
-static struct page *nilfs_get_page(struct inode *dir, unsigned long n)
+static void *nilfs_get_page(struct inode *dir, unsigned long n,
+		struct page **pagep)
 {
 	struct address_space *mapping = dir->i_mapping;
 	struct page *page = read_mapping_page(mapping, n, NULL);
+	void *kaddr;
 
-	if (!IS_ERR(page)) {
-		kmap(page);
-		if (unlikely(!PageChecked(page))) {
-			if (!nilfs_check_page(page))
-				goto fail;
-		}
+	if (IS_ERR(page))
+		return page;
+
+	kaddr = kmap(page);
+	if (unlikely(!PageChecked(page))) {
+		if (!nilfs_check_page(page))
+			goto fail;
 	}
-	return page;
+
+	*pagep = page;
+	return kaddr;
 
 fail:
 	nilfs_put_page(page);
@@ -269,14 +274,14 @@ static int nilfs_readdir(struct file *fi
 	for ( ; n < npages; n++, offset = 0) {
 		char *kaddr, *limit;
 		struct nilfs_dir_entry *de;
-		struct page *page = nilfs_get_page(inode, n);
+		struct page *page;
 
-		if (IS_ERR(page)) {
+		kaddr = nilfs_get_page(inode, n, &page);
+		if (IS_ERR(kaddr)) {
 			nilfs_error(sb, "bad page in #%lu", inode->i_ino);
 			ctx->pos += PAGE_SIZE - offset;
 			return -EIO;
 		}
-		kaddr = page_address(page);
 		de = (struct nilfs_dir_entry *)(kaddr + offset);
 		limit = kaddr + nilfs_last_byte(inode, n) -
 			NILFS_DIR_REC_LEN(1);
@@ -339,11 +344,9 @@ nilfs_find_entry(struct inode *dir, cons
 		start = 0;
 	n = start;
 	do {
-		char *kaddr;
+		char *kaddr = nilfs_get_page(dir, n, &page);
 
-		page = nilfs_get_page(dir, n);
-		if (!IS_ERR(page)) {
-			kaddr = page_address(page);
+		if (!IS_ERR(kaddr)) {
 			de = (struct nilfs_dir_entry *)kaddr;
 			kaddr += nilfs_last_byte(dir, n) - reclen;
 			while ((char *) de <= kaddr) {
@@ -381,15 +384,11 @@ found:
 
 struct nilfs_dir_entry *nilfs_dotdot(struct inode *dir, struct page **p)
 {
-	struct page *page = nilfs_get_page(dir, 0);
-	struct nilfs_dir_entry *de = NULL;
+	struct nilfs_dir_entry *de = nilfs_get_page(dir, 0, p);
 
-	if (!IS_ERR(page)) {
-		de = nilfs_next_entry(
-			(struct nilfs_dir_entry *)page_address(page));
-		*p = page;
-	}
-	return de;
+	if (IS_ERR(de))
+		return NULL;
+	return nilfs_next_entry(de);
 }
 
 ino_t nilfs_inode_by_name(struct inode *dir, const struct qstr *qstr)
@@ -451,12 +450,11 @@ int nilfs_add_link(struct dentry *dentry
 	for (n = 0; n <= npages; n++) {
 		char *dir_end;
 
-		page = nilfs_get_page(dir, n);
-		err = PTR_ERR(page);
-		if (IS_ERR(page))
+		kaddr = nilfs_get_page(dir, n, &page);
+		err = PTR_ERR(kaddr);
+		if (IS_ERR(kaddr))
 			goto out;
 		lock_page(page);
-		kaddr = page_address(page);
 		dir_end = kaddr + nilfs_last_byte(dir, n);
 		de = (struct nilfs_dir_entry *)kaddr;
 		kaddr += PAGE_SIZE - reclen;
@@ -618,11 +616,10 @@ int nilfs_empty_dir(struct inode *inode)
 		char *kaddr;
 		struct nilfs_dir_entry *de;
 
-		page = nilfs_get_page(inode, i);
-		if (IS_ERR(page))
+		kaddr = nilfs_get_page(inode, i, &page);
+		if (IS_ERR(kaddr))
 			continue;
 
-		kaddr = page_address(page);
 		de = (struct nilfs_dir_entry *)kaddr;
 		kaddr += nilfs_last_byte(inode, i) - NILFS_DIR_REC_LEN(1);
 
_

Patches currently in -mm which might be from willy@infradead.org are

mm-add-folio_zero_tail-and-use-it-in-ext4.patch
mm-add-folio_fill_tail-and-use-it-in-iomap.patch
gfs2-convert-stuffed_readpage-to-stuffed_read_folio.patch
mm-remove-test_set_page_writeback.patch
afs-do-not-test-the-return-value-of-folio_start_writeback.patch
smb-do-not-test-the-return-value-of-folio_start_writeback.patch
mm-return-void-from-folio_start_writeback-and-related-functions.patch
mm-make-mapping_evict_folio-the-preferred-way-to-evict-clean-folios.patch
mm-convert-__do_fault-to-use-a-folio.patch
mm-use-mapping_evict_folio-in-truncate_error_page.patch
mm-convert-soft_offline_in_use_page-to-use-a-folio.patch
mm-convert-isolate_page-to-mf_isolate_folio.patch
mm-remove-invalidate_inode_page.patch
buffer-return-bool-from-grow_dev_folio.patch
buffer-calculate-block-number-inside-folio_init_buffers.patch
buffer-fix-grow_buffers-for-block-size-page_size.patch
buffer-cast-block-to-loff_t-before-shifting-it.patch
buffer-fix-various-functions-for-block-size-page_size.patch
buffer-handle-large-folios-in-__block_write_begin_int.patch
buffer-fix-more-functions-for-block-size-page_size.patch
gfp-include-__gfp_nowarn-in-gfp_nowait.patch
memory-failure-use-a-folio-in-me_pagecache_clean.patch
memory-failure-use-a-folio-in-me_pagecache_dirty.patch
memory-failure-convert-delete_from_lru_cache-to-take-a-folio.patch
memory-failure-use-a-folio-in-me_huge_page.patch
memory-failure-convert-truncate_error_page-to-truncate_error_folio.patch
fs-convert-error_remove_page-to-error_remove_folio.patch
nilfs2-add-nilfs_end_folio_io.patch
nilfs2-convert-nilfs_abort_logs-to-use-folios.patch
nilfs2-convert-nilfs_segctor_complete_write-to-use-folios.patch
nilfs2-convert-nilfs_forget_buffer-to-use-a-folio.patch
nilfs2-convert-to-nilfs_folio_buffers_clean.patch
nilfs2-convert-nilfs_writepage-to-use-a-folio.patch
nilfs2-convert-nilfs_mdt_write_page-to-use-a-folio.patch
nilfs2-convert-to-nilfs_clear_folio_dirty.patch
nilfs2-convert-to-__nilfs_clear_folio_dirty.patch
nilfs2-convert-nilfs_segctor_prepare_write-to-use-folios.patch
nilfs2-convert-nilfs_page_mkwrite-to-use-a-folio.patch
nilfs2-convert-nilfs_mdt_create_block-to-use-a-folio.patch
nilfs2-convert-nilfs_mdt_submit_block-to-use-a-folio.patch
nilfs2-convert-nilfs_gccache_submit_read_data-to-use-a-folio.patch
nilfs2-convert-nilfs_btnode_create_block-to-use-a-folio.patch
nilfs2-convert-nilfs_btnode_submit_block-to-use-a-folio.patch
nilfs2-convert-nilfs_btnode_delete-to-use-a-folio.patch
nilfs2-convert-nilfs_btnode_prepare_change_key-to-use-a-folio.patch
nilfs2-convert-nilfs_btnode_commit_change_key-to-use-a-folio.patch
nilfs2-convert-nilfs_btnode_abort_change_key-to-use-a-folio.patch
nilfs2-remove-page_address-from-nilfs_set_link.patch
nilfs2-remove-page_address-from-nilfs_add_link.patch
nilfs2-remove-page_address-from-nilfs_delete_entry.patch
nilfs2-return-the-mapped-address-from-nilfs_get_page.patch
nilfs2-pass-the-mapped-address-to-nilfs_check_page.patch
nilfs2-switch-to-kmap_local-for-directory-handling.patch
nilfs2-add-nilfs_get_folio.patch
nilfs2-convert-nilfs_readdir-to-use-a-folio.patch
nilfs2-convert-nilfs_find_entry-to-use-a-folio.patch
nilfs2-convert-nilfs_rename-to-use-folios.patch
nilfs2-convert-nilfs_add_link-to-use-a-folio.patch
nilfs2-convert-nilfs_empty_dir-to-use-a-folio.patch
nilfs2-convert-nilfs_make_empty-to-use-a-folio.patch
nilfs2-convert-nilfs_prepare_chunk-and-nilfs_commit_chunk-to-folios.patch
nilfs2-convert-nilfs_page_bug-to-nilfs_folio_bug.patch