Re: [PATCH v7 07/19] xfs: Factor out xfs_attr_leaf_addname helper

Chandan Rajendra
2020-02-28T13:12:17Z

On Sunday, February 23, 2020 7:35 AM Allison Collins wrote:
> Factor out new helper function xfs_attr_leaf_try_add. Because new delayed attribute
> routines cannot roll transactions, we carve off the parts of xfs_attr_leaf_addname
> that we can use, and move the commit into the calling function.
>

I don't see any logical errors.

Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>

> Signed-off-by: Allison Collins <allison.henderson@oracle.com>
> Reviewed-by: Brian Foster <bfoster@redhat.com>
> ---
> fs/xfs/libxfs/xfs_attr.c | 88 +++++++++++++++++++++++++++++++-----------------
> 1 file changed, 57 insertions(+), 31 deletions(-)
>
> diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
> index cf0cba7..b2f0780 100644
> --- a/fs/xfs/libxfs/xfs_attr.c
> +++ b/fs/xfs/libxfs/xfs_attr.c
> @@ -305,10 +305,30 @@ xfs_attr_set_args(
> }
> }
>
> - if (xfs_bmap_one_block(dp, XFS_ATTR_FORK))
> + if (xfs_bmap_one_block(dp, XFS_ATTR_FORK)) {
> error = xfs_attr_leaf_addname(args);
> - else
> - error = xfs_attr_node_addname(args);
> + if (error != -ENOSPC)
> + return error;
> +
> + /*
> + * Commit that transaction so that the node_addname()
> + * call can manage its own transactions.
> + */
> + error = xfs_defer_finish(&args->trans);
> + if (error)
> + return error;
> +
> + /*
> + * Commit the current trans (including the inode) and
> + * start a new one.
> + */
> + error = xfs_trans_roll_inode(&args->trans, dp);
> + if (error)
> + return error;
> +
> + }
> +
> + error = xfs_attr_node_addname(args);
> return error;
> }
>
> @@ -620,20 +640,21 @@ xfs_attr_shortform_addname(xfs_da_args_t *args)
> *========================================================================*/
>
> /*
> - * Add a name to the leaf attribute list structure
> + * Tries to add an attribute to an inode in leaf form
> *
> - * This leaf block cannot have a "remote" value, we only call this routine
> - * if bmap_one_block() says there is only one block (ie: no remote blks).
> + * This function is meant to execute as part of a delayed operation and leaves
> + * the transaction handling to the caller. On success the attribute is added
> + * and the inode and transaction are left dirty. If there is not enough space,
> + * the attr data is converted to node format and -ENOSPC is returned. Caller is
> + * responsible for handling the dirty inode and transaction or adding the attr
> + * in node format.
> */
> STATIC int
> -xfs_attr_leaf_addname(
> - struct xfs_da_args *args)
> +xfs_attr_leaf_try_add(
> + struct xfs_da_args *args,
> + struct xfs_buf *bp)
> {
> - struct xfs_buf *bp;
> - int retval, error, forkoff;
> - struct xfs_inode *dp = args->dp;
> -
> - trace_xfs_attr_leaf_addname(args);
> + int retval, error;
>
> /*
> * Look up the given attribute in the leaf block. Figure out if
> @@ -679,31 +700,36 @@ xfs_attr_leaf_addname(
> retval = xfs_attr3_leaf_add(bp, args);
> if (retval == -ENOSPC) {
> /*
> - * Promote the attribute list to the Btree format, then
> - * Commit that transaction so that the node_addname() call
> - * can manage its own transactions.
> + * Promote the attribute list to the Btree format.
> + * Unless an error occurs, retain the -ENOSPC retval
> */
> error = xfs_attr3_leaf_to_node(args);
> if (error)
> return error;
> - error = xfs_defer_finish(&args->trans);
> - if (error)
> - return error;
> + }
> + return retval;
> +}
>
> - /*
> - * Commit the current trans (including the inode) and start
> - * a new one.
> - */
> - error = xfs_trans_roll_inode(&args->trans, dp);
> - if (error)
> - return error;
>
> - /*
> - * Fob the whole rest of the problem off on the Btree code.
> - */
> - error = xfs_attr_node_addname(args);
> +/*
> + * Add a name to the leaf attribute list structure
> + *
> + * This leaf block cannot have a "remote" value, we only call this routine
> + * if bmap_one_block() says there is only one block (ie: no remote blks).
> + */
> +STATIC int
> +xfs_attr_leaf_addname(
> + struct xfs_da_args *args)
> +{
> + int error, forkoff;
> + struct xfs_buf *bp = NULL;
> + struct xfs_inode *dp = args->dp;
> +
> + trace_xfs_attr_leaf_addname(args);
> +
> + error = xfs_attr_leaf_try_add(args, bp);
> + if (error)
> return error;
> - }
>
> /*
> * Commit the transaction that added the attr name so that
>

--
chandan