ext4: clear journal restart indication after inserting extent

[PATCH] ext4: clear journal restart indication after inserting extent

Posted by Yichong Chen 2 weeks, 2 days ago

ext4_datasem_ensure_credits() returns 1 when it successfully restarts
the transaction. finish_range() leaves that value in retval when the
subsequent ext4_ext_insert_extent() succeeds. Its callers interpret any
nonzero return as a migration failure, so they stop building the extent
tree and take the cleanup path instead of completing the migration.

Before ext4_ext_insert_extent() was changed to return a path, its integer
return value overwrote the restart indication. Restore that behavior with
PTR_ERR_OR_ZERO(), preserving insertion errors and returning zero on
success.

Fixes: f7d1331f16a8 ("ext4: get rid of ppath in ext4_ext_insert_extent()")
Signed-off-by: Yichong Chen <chenyichong@uniontech.com>
---
 fs/ext4/migrate.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/fs/ext4/migrate.c b/fs/ext4/migrate.c
index 5d60ef10fe11..d467b5a13c62 100644
--- a/fs/ext4/migrate.c
+++ b/fs/ext4/migrate.c
@@ -53,8 +53,7 @@ static int finish_range(handle_t *handle, struct inode *inode,
 	if (retval < 0)
 		goto err_out;
 	path = ext4_ext_insert_extent(handle, inode, path, &newext, 0);
-	if (IS_ERR(path))
-		retval = PTR_ERR(path);
+	retval = PTR_ERR_OR_ZERO(path);
 err_out:
 	up_write((&EXT4_I(inode)->i_data_sem));
 	ext4_free_ext_path(path);
-- 
2.51.0

Re: [PATCH] ext4: clear journal restart indication after inserting extent

Posted by Jan Kara 2 weeks, 2 days ago

On Wed 09-09-26 11:35:42, Yichong Chen wrote:
> ext4_datasem_ensure_credits() returns 1 when it successfully restarts
> the transaction. finish_range() leaves that value in retval when the
> subsequent ext4_ext_insert_extent() succeeds. Its callers interpret any
> nonzero return as a migration failure, so they stop building the extent
> tree and take the cleanup path instead of completing the migration.
> 
> Before ext4_ext_insert_extent() was changed to return a path, its integer
> return value overwrote the restart indication. Restore that behavior with
> PTR_ERR_OR_ZERO(), preserving insertion errors and returning zero on
> success.
> 
> Fixes: f7d1331f16a8 ("ext4: get rid of ppath in ext4_ext_insert_extent()")
> Signed-off-by: Yichong Chen <chenyichong@uniontech.com>

Looks good. Feel free to add:

Reviewed-by: Jan Kara <jack@suse.cz>

								Honza

> ---
>  fs/ext4/migrate.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/fs/ext4/migrate.c b/fs/ext4/migrate.c
> index 5d60ef10fe11..d467b5a13c62 100644
> --- a/fs/ext4/migrate.c
> +++ b/fs/ext4/migrate.c
> @@ -53,8 +53,7 @@ static int finish_range(handle_t *handle, struct inode *inode,
>  	if (retval < 0)
>  		goto err_out;
>  	path = ext4_ext_insert_extent(handle, inode, path, &newext, 0);
> -	if (IS_ERR(path))
> -		retval = PTR_ERR(path);
> +	retval = PTR_ERR_OR_ZERO(path);
>  err_out:
>  	up_write((&EXT4_I(inode)->i_data_sem));
>  	ext4_free_ext_path(path);
> -- 
> 2.51.0
> 
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR