On Thu, Feb 4, 2021 at 10:23 AM Naohiro Aota <naohiro.aota@xxxxxxx> wrote:
>
> This is the 3/3 patch to enable tree-log on zoned filesystems.
>
> The allocation order of nodes of "fs_info->log_root_tree" and nodes of
> "root->log_root" is not the same as the writing order of them. So, the
> writing causes unaligned write errors.
>
> Reorder the allocation of them by delaying allocation of the root node of
> "fs_info->log_root_tree," so that the node buffers can go out sequentially
> to devices.
>
> Cc: Filipe Manana <fdmanana@xxxxxxxxx>
> Reviewed-by: Josef Bacik <josef@xxxxxxxxxxxxxx>
> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
> Signed-off-by: Naohiro Aota <naohiro.aota@xxxxxxx>
> ---
> fs/btrfs/disk-io.c | 12 +++++++-----
> fs/btrfs/tree-log.c | 27 +++++++++++++++++++++------
> 2 files changed, 28 insertions(+), 11 deletions(-)
>
> diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
> index 84c6650d5ef7..c2576c5fe62e 100644
> --- a/fs/btrfs/disk-io.c
> +++ b/fs/btrfs/disk-io.c
> @@ -1298,16 +1298,18 @@ int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
> struct btrfs_fs_info *fs_info)
> {
> struct btrfs_root *log_root;
> - int ret;
>
> log_root = alloc_log_tree(trans, fs_info);
> if (IS_ERR(log_root))
> return PTR_ERR(log_root);
>
> - ret = btrfs_alloc_log_tree_node(trans, log_root);
> - if (ret) {
> - btrfs_put_root(log_root);
> - return ret;
> + if (!btrfs_is_zoned(fs_info)) {
> + int ret = btrfs_alloc_log_tree_node(trans, log_root);
> +
> + if (ret) {
> + btrfs_put_root(log_root);
> + return ret;
> + }
> }
>
> WARN_ON(fs_info->log_root_tree);
> diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
> index 8be3164d4c5d..7ba044bfa9b1 100644
> --- a/fs/btrfs/tree-log.c
> +++ b/fs/btrfs/tree-log.c
> @@ -3159,6 +3159,19 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
> list_add_tail(&root_log_ctx.list, &log_root_tree->log_ctxs[index2]);
> root_log_ctx.log_transid = log_root_tree->log_transid;
>
> + if (btrfs_is_zoned(fs_info)) {
> + mutex_lock(&fs_info->tree_log_mutex);
> + if (!log_root_tree->node) {
As commented in v14, the log root tree is not protected by
fs_info->tree_log_mutex anymore.
It is fs_info->tree_root->log_mutex as of 5.10.
Everything else was addressed and looks good.
Thanks.
> + ret = btrfs_alloc_log_tree_node(trans, log_root_tree);
> + if (ret) {
> + mutex_unlock(&fs_info->tree_log_mutex);
> + mutex_unlock(&log_root_tree->log_mutex);
> + goto out;
> + }
> + }
> + mutex_unlock(&fs_info->tree_log_mutex);
> + }
> +
> /*
> * Now we are safe to update the log_root_tree because we're under the
> * log_mutex, and we're a current writer so we're holding the commit
> @@ -3317,12 +3330,14 @@ static void free_log_tree(struct btrfs_trans_handle *trans,
> .process_func = process_one_buffer
> };
>
> - ret = walk_log_tree(trans, log, &wc);
> - if (ret) {
> - if (trans)
> - btrfs_abort_transaction(trans, ret);
> - else
> - btrfs_handle_fs_error(log->fs_info, ret, NULL);
> + if (log->node) {
> + ret = walk_log_tree(trans, log, &wc);
> + if (ret) {
> + if (trans)
> + btrfs_abort_transaction(trans, ret);
> + else
> + btrfs_handle_fs_error(log->fs_info, ret, NULL);
> + }
> }
>
> clear_extent_bits(&log->dirty_log_pages, 0, (u64)-1,
> --
> 2.30.0
>
--
Filipe David Manana,
“Whether you think you can, or you think you can't — you're right.”
