From: Eric Biggers <ebiggers@google.com>
Date: Thu, 2 Feb 2023 17:02:39 -0800
Subject: [PATCH] f2fs: fix cgroup writeback accounting with fs-layer
 encryption
References: bsc#1012628
Patch-mainline: 6.2.3
Git-commit: 844545c51a5b2a524b22a2fe9d0b353b827d24b4

commit 844545c51a5b2a524b22a2fe9d0b353b827d24b4 upstream.

When writing a page from an encrypted file that is using
filesystem-layer encryption (not inline encryption), f2fs encrypts the
pagecache page into a bounce page, then writes the bounce page.

It also passes the bounce page to wbc_account_cgroup_owner().  That's
incorrect, because the bounce page is a newly allocated temporary page
that doesn't have the memory cgroup of the original pagecache page.
This makes wbc_account_cgroup_owner() not account the I/O to the owner
of the pagecache page as it should.

Fix this by always passing the pagecache page to
wbc_account_cgroup_owner().

Fixes: 578c647879f7 ("f2fs: implement cgroup writeback support")
Cc: stable@vger.kernel.org
Reported-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 fs/f2fs/data.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 97e81659..ce4d539b 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -741,7 +741,7 @@ int f2fs_submit_page_bio(struct f2fs_io_info *fio)
 	}
 
 	if (fio->io_wbc && !is_read_io(fio->op))
-		wbc_account_cgroup_owner(fio->io_wbc, page, PAGE_SIZE);
+		wbc_account_cgroup_owner(fio->io_wbc, fio->page, PAGE_SIZE);
 
 	inc_page_count(fio->sbi, is_read_io(fio->op) ?
 			__read_io_type(page) : WB_DATA_TYPE(fio->page));
@@ -948,7 +948,7 @@ int f2fs_merge_page_bio(struct f2fs_io_info *fio)
 	}
 
 	if (fio->io_wbc)
-		wbc_account_cgroup_owner(fio->io_wbc, page, PAGE_SIZE);
+		wbc_account_cgroup_owner(fio->io_wbc, fio->page, PAGE_SIZE);
 
 	inc_page_count(fio->sbi, WB_DATA_TYPE(page));
 
@@ -1022,7 +1022,7 @@ void f2fs_submit_page_write(struct f2fs_io_info *fio)
 	}
 
 	if (fio->io_wbc)
-		wbc_account_cgroup_owner(fio->io_wbc, bio_page, PAGE_SIZE);
+		wbc_account_cgroup_owner(fio->io_wbc, fio->page, PAGE_SIZE);
 
 	io->last_block_in_bio = fio->new_blkaddr;
 
-- 
2.35.3