This is preparatory patch to remove @bdev parameter from
submit_extent_page. It can't be removed completely, because the cgroups
need it for wbc when initializing the bio
wbc_init_bio
bio_associate_blkg_from_css
dereference bdev->bi_disk->queue
The bdev pointer is the same as latest_bdev, thus no functional change.
We can retrieve it from fs_devices that's reachable through several
dereferences. The local variable shadows the parameter, but that's only
temporary.
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
---
This is a prerequisite for patchset to avoid crash when cgroups are
enabled
https://lore.kernel.org/linux-btrfs/cover.1570474492.git.dsterba@xxxxxxxx/
fs/btrfs/extent_io.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index ceb3c028894e..9a2339a54a9d 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2987,13 +2987,16 @@ static int submit_extent_page(unsigned int opf, struct extent_io_tree *tree,
}
bio = btrfs_bio_alloc(offset);
- bio_set_dev(bio, bdev);
bio_add_page(bio, page, page_size, pg_offset);
bio->bi_end_io = end_io_func;
bio->bi_private = tree;
bio->bi_write_hint = page->mapping->host->i_write_hint;
bio->bi_opf = opf;
if (wbc) {
+ struct block_device *bdev;
+
+ bdev = BTRFS_I(page->mapping->host)->root->fs_info->fs_devices->latest_bdev;
+ bio_set_dev(bio, bdev);
wbc_init_bio(wbc, bio);
wbc_account_cgroup_owner(wbc, page, page_size);
}
--
2.24.0
