Re: [PATCH v18 10/11] xfs: Add delay ready attr remove routines

[Chandan Babu R <chandanrlinux@gmail.com>]

On 28 Apr 2021 at 13:39, Allison Henderson wrote:
> This patch modifies the attr remove routines to be delay ready. This
> means they no longer roll or commit transactions, but instead return
> -EAGAIN to have the calling routine roll and refresh the transaction. In
> this series, xfs_attr_remove_args is merged with
> xfs_attr_node_removename become a new function, xfs_attr_remove_iter.
> This new version uses a sort of state machine like switch to keep track
> of where it was when EAGAIN was returned. A new version of
> xfs_attr_remove_args consists of a simple loop to refresh the
> transaction until the operation is completed. A new XFS_DAC_DEFER_FINISH
> flag is used to finish the transaction where ever the existing code used
> to.
>
> Calls to xfs_attr_rmtval_remove are replaced with the delay ready
> version __xfs_attr_rmtval_remove. We will rename
> __xfs_attr_rmtval_remove back to xfs_attr_rmtval_remove when we are
> done.
>
> xfs_attr_rmtval_remove itself is still in use by the set routines (used
> during a rename).  For reasons of preserving existing function, we
> modify xfs_attr_rmtval_remove to call xfs_defer_finish when the flag is
> set.  Similar to how xfs_attr_remove_args does here.  Once we transition
> the set routines to be delay ready, xfs_attr_rmtval_remove is no longer
> used and will be removed.
>
> This patch also adds a new struct xfs_delattr_context, which we will use
> to keep track of the current state of an attribute operation. The new
> xfs_delattr_state enum is used to track various operations that are in
> progress so that we know not to repeat them, and resume where we left
> off before EAGAIN was returned to cycle out the transaction. Other
> members take the place of local variables that need to retain their
> values across multiple function recalls.  See xfs_attr.h for a more
> detailed diagram of the states.
>

Sorry, My previous response to this patch was incorrectly formatted. Fixing it
now.

The error handling issues pointed out in the previous version of the this
patch have been fixed.

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

--
chandan