Re: [PATCH v1 3/7] vfio/ccw: move private initialization to callback

From: Matthew Rosato
Date: Fri Oct 28 2022 - 14:53:08 EST


On 10/19/22 12:21 PM, Eric Farman wrote:
> There's already a device initialization callback that is
> used to initialize the release completion workaround.

As discussed off-list, maybe clarify what callback you're talking about here and/or reference the commit that added it.

>
> Move the other elements of the vfio_ccw_private struct that
> require distinct initialization over to that routine.
>
> Signed-off-by: Eric Farman <farman@xxxxxxxxxxxxx>
> ---
> drivers/s390/cio/vfio_ccw_drv.c | 57 +++--------------------------
> drivers/s390/cio/vfio_ccw_ops.c | 43 ++++++++++++++++++++++
> drivers/s390/cio/vfio_ccw_private.h | 7 +++-
> 3 files changed, 55 insertions(+), 52 deletions(-)
>
> diff --git a/drivers/s390/cio/vfio_ccw_drv.c b/drivers/s390/cio/vfio_ccw_drv.c
> index 4ee953c8ae39..cc9ed2fd970f 100644
> --- a/drivers/s390/cio/vfio_ccw_drv.c
> +++ b/drivers/s390/cio/vfio_ccw_drv.c
> @@ -24,10 +24,10 @@
> #include "vfio_ccw_private.h"
>
> struct workqueue_struct *vfio_ccw_work_q;
> -static struct kmem_cache *vfio_ccw_io_region;
> -static struct kmem_cache *vfio_ccw_cmd_region;
> -static struct kmem_cache *vfio_ccw_schib_region;
> -static struct kmem_cache *vfio_ccw_crw_region;
> +struct kmem_cache *vfio_ccw_io_region;
> +struct kmem_cache *vfio_ccw_cmd_region;
> +struct kmem_cache *vfio_ccw_schib_region;
> +struct kmem_cache *vfio_ccw_crw_region;
>
> debug_info_t *vfio_ccw_debug_msg_id;
> debug_info_t *vfio_ccw_debug_trace_id;
> @@ -74,7 +74,7 @@ int vfio_ccw_sch_quiesce(struct subchannel *sch)
> return ret;
> }
>
> -static void vfio_ccw_sch_io_todo(struct work_struct *work)
> +void vfio_ccw_sch_io_todo(struct work_struct *work)
> {
> struct vfio_ccw_private *private;
> struct irb *irb;
> @@ -110,7 +110,7 @@ static void vfio_ccw_sch_io_todo(struct work_struct *work)
> eventfd_signal(private->io_trigger, 1);
> }
>
> -static void vfio_ccw_crw_todo(struct work_struct *work)
> +void vfio_ccw_crw_todo(struct work_struct *work)
> {
> struct vfio_ccw_private *private;
>
> @@ -154,52 +154,7 @@ static struct vfio_ccw_private *vfio_ccw_alloc_private(struct subchannel *sch)
> if (!private)
> return ERR_PTR(-ENOMEM);

Not sure we really still need vfio_ccw_alloc_private() now or whether you can just kzalloc() inline right in vfio_ccw_sch_probe()

Either way:

Reviewed-by: Matthew Rosato <mjrosato@xxxxxxxxxxxxx>


>
> - mutex_init(&private->io_mutex);
> - private->state = VFIO_CCW_STATE_STANDBY;
> - INIT_LIST_HEAD(&private->crw);
> - INIT_WORK(&private->io_work, vfio_ccw_sch_io_todo);
> - INIT_WORK(&private->crw_work, vfio_ccw_crw_todo);
> -
> - private->cp.guest_cp = kcalloc(CCWCHAIN_LEN_MAX, sizeof(struct ccw1),
> - GFP_KERNEL);
> - if (!private->cp.guest_cp)
> - goto out_free_private;
> -
> - private->io_region = kmem_cache_zalloc(vfio_ccw_io_region,
> - GFP_KERNEL | GFP_DMA);
> - if (!private->io_region)
> - goto out_free_cp;
> -
> - private->cmd_region = kmem_cache_zalloc(vfio_ccw_cmd_region,
> - GFP_KERNEL | GFP_DMA);
> - if (!private->cmd_region)
> - goto out_free_io;
> -
> - private->schib_region = kmem_cache_zalloc(vfio_ccw_schib_region,
> - GFP_KERNEL | GFP_DMA);
> -
> - if (!private->schib_region)
> - goto out_free_cmd;
> -
> - private->crw_region = kmem_cache_zalloc(vfio_ccw_crw_region,
> - GFP_KERNEL | GFP_DMA);
> -
> - if (!private->crw_region)
> - goto out_free_schib;
> return private;
> -
> -out_free_schib:
> - kmem_cache_free(vfio_ccw_schib_region, private->schib_region);
> -out_free_cmd:
> - kmem_cache_free(vfio_ccw_cmd_region, private->cmd_region);
> -out_free_io:
> - kmem_cache_free(vfio_ccw_io_region, private->io_region);
> -out_free_cp:
> - kfree(private->cp.guest_cp);
> -out_free_private:
> - mutex_destroy(&private->io_mutex);
> - kfree(private);
> - return ERR_PTR(-ENOMEM);
> }
>
> static void vfio_ccw_free_private(struct vfio_ccw_private *private)
> diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c
> index cf383c729d53..626b8eb3507b 100644
> --- a/drivers/s390/cio/vfio_ccw_ops.c
> +++ b/drivers/s390/cio/vfio_ccw_ops.c
> @@ -50,8 +50,51 @@ static int vfio_ccw_mdev_init_dev(struct vfio_device *vdev)
> struct vfio_ccw_private *private =
> container_of(vdev, struct vfio_ccw_private, vdev);
>
> + mutex_init(&private->io_mutex);
> + private->state = VFIO_CCW_STATE_STANDBY;
> + INIT_LIST_HEAD(&private->crw);
> + INIT_WORK(&private->io_work, vfio_ccw_sch_io_todo);
> + INIT_WORK(&private->crw_work, vfio_ccw_crw_todo);
> init_completion(&private->release_comp);
> +
> + private->cp.guest_cp = kcalloc(CCWCHAIN_LEN_MAX, sizeof(struct ccw1),
> + GFP_KERNEL);
> + if (!private->cp.guest_cp)
> + goto out_free_private;
> +
> + private->io_region = kmem_cache_zalloc(vfio_ccw_io_region,
> + GFP_KERNEL | GFP_DMA);
> + if (!private->io_region)
> + goto out_free_cp;
> +
> + private->cmd_region = kmem_cache_zalloc(vfio_ccw_cmd_region,
> + GFP_KERNEL | GFP_DMA);
> + if (!private->cmd_region)
> + goto out_free_io;
> +
> + private->schib_region = kmem_cache_zalloc(vfio_ccw_schib_region,
> + GFP_KERNEL | GFP_DMA);
> + if (!private->schib_region)
> + goto out_free_cmd;
> +
> + private->crw_region = kmem_cache_zalloc(vfio_ccw_crw_region,
> + GFP_KERNEL | GFP_DMA);
> + if (!private->crw_region)
> + goto out_free_schib;
> +
> return 0;
> +
> +out_free_schib:
> + kmem_cache_free(vfio_ccw_schib_region, private->schib_region);
> +out_free_cmd:
> + kmem_cache_free(vfio_ccw_cmd_region, private->cmd_region);
> +out_free_io:
> + kmem_cache_free(vfio_ccw_io_region, private->io_region);
> +out_free_cp:
> + kfree(private->cp.guest_cp);
> +out_free_private:
> + mutex_destroy(&private->io_mutex);
> + return -ENOMEM;
> }
>
> static int vfio_ccw_mdev_probe(struct mdev_device *mdev)
> diff --git a/drivers/s390/cio/vfio_ccw_private.h b/drivers/s390/cio/vfio_ccw_private.h
> index 0fdff1435230..b35940057073 100644
> --- a/drivers/s390/cio/vfio_ccw_private.h
> +++ b/drivers/s390/cio/vfio_ccw_private.h
> @@ -116,6 +116,8 @@ struct vfio_ccw_private {
> } __aligned(8);
>
> int vfio_ccw_sch_quiesce(struct subchannel *sch);
> +void vfio_ccw_sch_io_todo(struct work_struct *work);
> +void vfio_ccw_crw_todo(struct work_struct *work);
>
> extern struct mdev_driver vfio_ccw_mdev_driver;
>
> @@ -163,7 +165,10 @@ static inline void vfio_ccw_fsm_event(struct vfio_ccw_private *private,
> }
>
> extern struct workqueue_struct *vfio_ccw_work_q;
> -
> +extern struct kmem_cache *vfio_ccw_io_region;
> +extern struct kmem_cache *vfio_ccw_cmd_region;
> +extern struct kmem_cache *vfio_ccw_schib_region;
> +extern struct kmem_cache *vfio_ccw_crw_region;
>
> /* s390 debug feature, similar to base cio */
> extern debug_info_t *vfio_ccw_debug_msg_id;