[PATCH 41/43] btrfs: make the init of static elements in fs_info separate

Josef Bacik
2020-01-17T21:27:19Z

In adding things like eb leak checking and root leak checking there were
a lot of weird corner cases that come from the fact that

1) We do not init the fs_info until we get to open_ctree time in the
normal case and

2) The test infrastructure half-init's the fs_info for things that it
needs.

This makes it really annoying to make changes because you have to add
init in two different places, have special cases for testing fs_info's
that may not have certain things init'ed, and cases for fs_info's that
didn't make it to open_ctree and thus are not fully init'ed.

Fix this by extracting out the non-allocating init of the fs info into
it's own public function and use that to make sure we're all getting
consistent views of an allocated fs_info.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
fs/btrfs/disk-io.c | 19 +++++++++++--------
fs/btrfs/disk-io.h | 1 +
fs/btrfs/super.c | 1 +
fs/btrfs/tests/btrfs-tests.c | 28 ++++------------------------
4 files changed, 17 insertions(+), 32 deletions(-)

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index b7e4313bdc6f..87bad959b1a5 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -2649,10 +2649,8 @@ static int __cold init_tree_roots(struct btrfs_fs_info *fs_info)
return ret;
}

-static int init_fs_info(struct btrfs_fs_info *fs_info, struct super_block *sb)
+void btrfs_init_fs_info(struct btrfs_fs_info *fs_info)
{
- int ret;
-
INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
INIT_RADIX_TREE(&fs_info->buffer_radix, GFP_ATOMIC);
INIT_LIST_HEAD(&fs_info->trans_list);
@@ -2696,7 +2694,6 @@ static int init_fs_info(struct btrfs_fs_info *fs_info, struct super_block *sb)
atomic_set(&fs_info->reada_works_cnt, 0);
atomic_set(&fs_info->nr_delayed_iputs, 0);
atomic64_set(&fs_info->tree_mod_seq, 0);
- fs_info->sb = sb;
fs_info->max_inline = BTRFS_DEFAULT_MAX_INLINE;
fs_info->metadata_ratio = 0;
fs_info->defrag_inodes = RB_ROOT;
@@ -2722,9 +2719,6 @@ static int init_fs_info(struct btrfs_fs_info *fs_info, struct super_block *sb)
btrfs_init_balance(fs_info);
btrfs_init_async_reclaim_work(&fs_info->async_reclaim_work);

- sb->s_blocksize = BTRFS_BDEV_BLOCKSIZE;
- sb->s_blocksize_bits = blksize_bits(BTRFS_BDEV_BLOCKSIZE);
-
spin_lock_init(&fs_info->block_group_cache_lock);
fs_info->block_group_cache_tree = RB_ROOT;
fs_info->first_logical_byte = (u64)-1;
@@ -2769,6 +2763,15 @@ static int init_fs_info(struct btrfs_fs_info *fs_info, struct super_block *sb)
fs_info->swapfile_pins = RB_ROOT;

fs_info->send_in_progress = 0;
+}
+
+static int init_mount_fs_info(struct btrfs_fs_info *fs_info, struct super_block *sb)
+{
+ int ret;
+
+ fs_info->sb = sb;
+ sb->s_blocksize = BTRFS_BDEV_BLOCKSIZE;
+ sb->s_blocksize_bits = blksize_bits(BTRFS_BDEV_BLOCKSIZE);

ret = init_srcu_struct(&fs_info->subvol_srcu);
if (ret)
@@ -2833,7 +2836,7 @@ int __cold open_ctree(struct super_block *sb,
int clear_free_space_tree = 0;
int level;

- ret = init_fs_info(fs_info, sb);
+ ret = init_mount_fs_info(fs_info, sb);
if (ret) {
err = ret;
goto fail;
diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index 97e7ac474a52..2414d572bc9a 100644
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -39,6 +39,7 @@ static inline u64 btrfs_sb_offset(int mirror)
struct btrfs_device;
struct btrfs_fs_devices;

+void btrfs_init_fs_info(struct btrfs_fs_info *fs_info);
int btrfs_verify_level_key(struct extent_buffer *eb, int level,
struct btrfs_key *first_key, u64 parent_transid);
struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 8ce292a47634..8d5bb8dfed0d 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -1531,6 +1531,7 @@ static struct dentry *btrfs_mount_root(struct file_system_type *fs_type,
error = -ENOMEM;
goto error_sec_opts;
}
+ btrfs_init_fs_info(fs_info);

fs_info->super_copy = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL);
fs_info->super_for_commit = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL);
diff --git a/fs/btrfs/tests/btrfs-tests.c b/fs/btrfs/tests/btrfs-tests.c
index 27f5b662d2cb..683381a692bc 100644
--- a/fs/btrfs/tests/btrfs-tests.c
+++ b/fs/btrfs/tests/btrfs-tests.c
@@ -120,6 +120,8 @@ struct btrfs_fs_info *btrfs_alloc_dummy_fs_info(u32 nodesize, u32 sectorsize)
kfree(fs_info);
return NULL;
}
+ INIT_LIST_HEAD(&fs_info->fs_devices->devices);
+
fs_info->super_copy = kzalloc(sizeof(struct btrfs_super_block),
GFP_KERNEL);
if (!fs_info->super_copy) {
@@ -128,6 +130,8 @@ struct btrfs_fs_info *btrfs_alloc_dummy_fs_info(u32 nodesize, u32 sectorsize)
return NULL;
}

+ btrfs_init_fs_info(fs_info);
+
fs_info->nodesize = nodesize;
fs_info->sectorsize = sectorsize;

@@ -138,30 +142,6 @@ struct btrfs_fs_info *btrfs_alloc_dummy_fs_info(u32 nodesize, u32 sectorsize)
return NULL;
}

- spin_lock_init(&fs_info->buffer_lock);
- spin_lock_init(&fs_info->qgroup_lock);
- spin_lock_init(&fs_info->super_lock);
- spin_lock_init(&fs_info->fs_roots_radix_lock);
- spin_lock_init(&fs_info->tree_mod_seq_lock);
- mutex_init(&fs_info->qgroup_ioctl_lock);
- mutex_init(&fs_info->qgroup_rescan_lock);
- rwlock_init(&fs_info->tree_mod_log_lock);
- fs_info->running_transaction = NULL;
- fs_info->qgroup_tree = RB_ROOT;
- fs_info->qgroup_ulist = NULL;
- atomic64_set(&fs_info->tree_mod_seq, 0);
- INIT_LIST_HEAD(&fs_info->dirty_qgroups);
- INIT_LIST_HEAD(&fs_info->dead_roots);
- INIT_LIST_HEAD(&fs_info->tree_mod_seq_list);
- INIT_LIST_HEAD(&fs_info->fs_devices->devices);
- INIT_RADIX_TREE(&fs_info->buffer_radix, GFP_ATOMIC);
- INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC);
- extent_io_tree_init(fs_info, &fs_info->freed_extents[0],
- IO_TREE_FS_INFO_FREED_EXTENTS0, NULL);
- extent_io_tree_init(fs_info, &fs_info->freed_extents[1],
- IO_TREE_FS_INFO_FREED_EXTENTS1, NULL);
- extent_map_tree_init(&fs_info->mapping_tree);
- fs_info->pinned_extents = &fs_info->freed_extents[0];
set_bit(BTRFS_FS_STATE_DUMMY_FS_INFO, &fs_info->fs_state);

test_mnt->mnt_sb->s_fs_info = fs_info;
--
2.24.1