diff options
| author | Eric Biggers <ebiggers@google.com> | 2023-02-03 03:55:03 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-03-22 15:26:13 +0300 |
| commit | 74f30fa7c92e61e51c5e9ee3df5e5717c5d483ec (patch) | |
| tree | 54e73264b971d3c363e9452f55f5f2a41b838cfc | |
| parent | 04363512e510c11598b6d27511285e6779820df5 (diff) | |
| download | linux-74f30fa7c92e61e51c5e9ee3df5e5717c5d483ec.tar.xz | |
ext4: fix cgroup writeback accounting with fs-layer encryption
commit ffec85d53d0f39ee4680a2cf0795255e000e1feb upstream.
When writing a page from an encrypted file that is using
filesystem-layer encryption (not inline encryption), ext4 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: 001e4a8775f6 ("ext4: 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>
Link: https://lore.kernel.org/r/20230203005503.141557-1-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/ext4/page-io.c | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c index 3de933354a08..bf910f266469 100644 --- a/fs/ext4/page-io.c +++ b/fs/ext4/page-io.c @@ -388,7 +388,8 @@ static int io_submit_init_bio(struct ext4_io_submit *io, static int io_submit_add_bh(struct ext4_io_submit *io, struct inode *inode, - struct page *page, + struct page *pagecache_page, + struct page *bounce_page, struct buffer_head *bh) { int ret; @@ -403,10 +404,11 @@ submit_and_retry: return ret; io->io_bio->bi_write_hint = inode->i_write_hint; } - ret = bio_add_page(io->io_bio, page, bh->b_size, bh_offset(bh)); + ret = bio_add_page(io->io_bio, bounce_page ?: pagecache_page, + bh->b_size, bh_offset(bh)); if (ret != bh->b_size) goto submit_and_retry; - wbc_account_io(io->io_wbc, page, bh->b_size); + wbc_account_io(io->io_wbc, pagecache_page, bh->b_size); io->io_next_block++; return 0; } @@ -514,8 +516,7 @@ int ext4_bio_write_page(struct ext4_io_submit *io, do { if (!buffer_async_write(bh)) continue; - ret = io_submit_add_bh(io, inode, - data_page ? data_page : page, bh); + ret = io_submit_add_bh(io, inode, page, data_page, bh); if (ret) { /* * We only get here on ENOMEM. Not much else |