[RFC PATCH v3 7/8] ext4: remove bdev_try_to_free_page() callback
From: Zhang Yi <yi.zhang@huawei.com>
Date: 2021-05-27 13:47:29
Subsystem:
ext4 file system, filesystems (vfs and infrastructure), the rest · Maintainers:
"Theodore Ts'o", Alexander Viro, Christian Brauner, Linus Torvalds
After we introduce a jbd2 shrinker to release checkpointed buffer's journal head, we could free buffer without bdev_try_to_free_page() under memory pressure. So this patch remove the whole bdev_try_to_free_page() callback directly. It also remove many use-after-free issues relate to it together. Signed-off-by: Zhang Yi <yi.zhang@huawei.com> --- fs/ext4/super.c | 21 --------------------- 1 file changed, 21 deletions(-)
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index bf6d0085e1b7..b778236d06e6 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c@@ -1442,26 +1442,6 @@ static int ext4_nfs_commit_metadata(struct inode *inode) return ext4_write_inode(inode, &wbc); } -/* - * Try to release metadata pages (indirect blocks, directories) which are - * mapped via the block device. Since these pages could have journal heads - * which would prevent try_to_free_buffers() from freeing them, we must use - * jbd2 layer's try_to_free_buffers() function to release them. - */ -static int bdev_try_to_free_page(struct super_block *sb, struct page *page, - gfp_t wait) -{ - journal_t *journal = EXT4_SB(sb)->s_journal; - - WARN_ON(PageChecked(page)); - if (!page_has_buffers(page)) - return 0; - if (journal) - return jbd2_journal_try_to_free_buffers(journal, page); - - return try_to_free_buffers(page); -} - #ifdef CONFIG_FS_ENCRYPTION static int ext4_get_context(struct inode *inode, void *ctx, size_t len) {
@@ -1656,7 +1636,6 @@ static const struct super_operations ext4_sops = { .quota_write = ext4_quota_write, .get_dquots = ext4_get_dquots, #endif - .bdev_try_to_free_page = bdev_try_to_free_page, }; static const struct export_operations ext4_export_ops = {
--
2.25.4