Re: [PATCH 1/8] bnxt_en: Add auxiliary driver support

From: Jakub Kicinski
Date: Tue Jan 10 2023 - 17:54:23 EST

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On Sat, 7 Jan 2023 19:02:01 -0800 Ajit Khaparde wrote:
> diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.c
> index 2e54bf4fc7a7..6c697172f042 100644
> --- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.c
> +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.c
> @@ -25,32 +25,37 @@
> #include "bnxt_hwrm.h"
> #include "bnxt_ulp.h"
>
> +static DEFINE_IDA(bnxt_aux_dev_ids);
> +
> static int bnxt_register_dev(struct bnxt_en_dev *edev, unsigned int ulp_id,
> struct bnxt_ulp_ops *ulp_ops, void *handle)
> {
> struct net_device *dev = edev->net;
> struct bnxt *bp = netdev_priv(dev);
> struct bnxt_ulp *ulp;
> + int rc = 0;
>
> - ASSERT_RTNL();
> if (ulp_id >= BNXT_MAX_ULP)
> return -EINVAL;
>
> ulp = &edev->ulp_tbl[ulp_id];
> if (rcu_access_pointer(ulp->ulp_ops)) {
> netdev_err(bp->dev, "ulp id %d already registered\n", ulp_id);
> - return -EBUSY;
> + rc = -EBUSY;
> + goto exit;

The change to jump to the return statement rater than return directly
seems unrelated to the rest of the patch, and wrong.

> }
> if (ulp_id == BNXT_ROCE_ULP) {
> unsigned int max_stat_ctxs;
>
> max_stat_ctxs = bnxt_get_max_func_stat_ctxs(bp);
> if (max_stat_ctxs <= BNXT_MIN_ROCE_STAT_CTXS ||
> - bp->cp_nr_rings == max_stat_ctxs)
> - return -ENOMEM;
> + bp->cp_nr_rings == max_stat_ctxs) {
> + rc = -ENOMEM;
> + goto exit;
> + }
> }
>
> - atomic_set(&ulp->ref_count, 0);
> + atomic_set(&ulp->ref_count, 1);
> ulp->handle = handle;
> rcu_assign_pointer(ulp->ulp_ops, ulp_ops);
>
> @@ -59,7 +64,8 @@ static int bnxt_register_dev(struct bnxt_en_dev *edev, unsigned int ulp_id,
> bnxt_hwrm_vnic_cfg(bp, 0);
> }
>
> - return 0;
> +exit:
> + return rc;
> }
>
> static int bnxt_unregister_dev(struct bnxt_en_dev *edev, unsigned int ulp_id)
> @@ -69,10 +75,11 @@ static int bnxt_unregister_dev(struct bnxt_en_dev *edev, unsigned int ulp_id)
> struct bnxt_ulp *ulp;
> int i = 0;
>
> - ASSERT_RTNL();
> if (ulp_id >= BNXT_MAX_ULP)
> return -EINVAL;
>
> + edev->flags |= BNXT_EN_FLAG_ULP_STOPPED;
> +
> ulp = &edev->ulp_tbl[ulp_id];
> if (!rcu_access_pointer(ulp->ulp_ops)) {
> netdev_err(bp->dev, "ulp id %d not registered\n", ulp_id);
> @@ -126,7 +133,6 @@ static int bnxt_req_msix_vecs(struct bnxt_en_dev *edev, unsigned int ulp_id,
> int total_vecs;
> int rc = 0;
>
> - ASSERT_RTNL();
> if (ulp_id != BNXT_ROCE_ULP)
> return -EINVAL;
>
> @@ -149,6 +155,7 @@ static int bnxt_req_msix_vecs(struct bnxt_en_dev *edev, unsigned int ulp_id,
> max_idx = min_t(int, bp->total_irqs, max_cp_rings);
> idx = max_idx - avail_msix;
> }
> +
> edev->ulp_tbl[ulp_id].msix_base = idx;
> edev->ulp_tbl[ulp_id].msix_requested = avail_msix;
> hw_resc = &bp->hw_resc;
> @@ -156,8 +163,10 @@ static int bnxt_req_msix_vecs(struct bnxt_en_dev *edev, unsigned int ulp_id,
> if (bp->total_irqs < total_vecs ||
> (BNXT_NEW_RM(bp) && hw_resc->resv_irqs < total_vecs)) {
> if (netif_running(dev)) {
> + rtnl_lock();

What prevents the device from going down after you check running
but before you take the lock?

> bnxt_close_nic(bp, true, false);
> rc = bnxt_open_nic(bp, true, false);
> + rtnl_unlock();
> } else {
> rc = bnxt_reserve_rings(bp, true);
> }

> @@ -475,6 +467,143 @@ static const struct bnxt_en_ops bnxt_en_ops_tbl = {
> .bnxt_register_fw_async_events = bnxt_register_async_events,
> };
>
> +void bnxt_aux_dev_free(struct bnxt *bp)
> +{
> + kfree(bp->aux_dev);
> + bp->aux_dev = NULL;
> +}
> +
> +static struct bnxt_aux_dev *bnxt_aux_dev_alloc(struct bnxt *bp)
> +{
> + struct bnxt_aux_dev *bnxt_adev;
> +
> + bnxt_adev = kzalloc(sizeof(*bnxt_adev), GFP_KERNEL);

double space

> + if (!bnxt_adev)
> + return NULL;
> +
> + return bnxt_adev;

This entire function is rather pointless.

If you really want it - it can be simply written as:

static struct bnxt_aux_dev *bnxt_aux_dev_alloc(struct bnxt *bp)
{
return kzalloc(sizeof(struct bnxt_aux_dev), GFP_KERNEL);
}

> +}
> +
> +void bnxt_rdma_aux_device_uninit(struct bnxt *bp)
> +{
> + struct bnxt_aux_dev *bnxt_adev;
> + struct auxiliary_device *adev;
> +
> + /* Skip if no auxiliary device init was done. */
> + if (!(bp->flags & BNXT_FLAG_ROCE_CAP))
> + return;
> +
> + bnxt_adev = bp->aux_dev;
> + adev = &bnxt_adev->aux_dev;
> + auxiliary_device_delete(adev);

auxiliary_device_delete() waits for all the references to disappear?
The lifetime rules between adev and "edev" seem a little odd to me,
maybe I'm not familiar enough with auxdev.

> + auxiliary_device_uninit(adev);
> + if (bnxt_adev->id >= 0)
> + ida_free(&bnxt_aux_dev_ids, bnxt_adev->id);
> +}
> +
> +void bnxt_rdma_aux_device_init(struct bnxt *bp)
> +{
> + int rc;
> +
> + if (bp->flags & BNXT_FLAG_ROCE_CAP) {

flip the condition and return early, don't indent an entire function.

> + bp->aux_dev = bnxt_aux_dev_alloc(bp);
> + if (!bp->aux_dev)
> + goto skip_ida_init;
> +
> + bp->aux_dev->id = ida_alloc(&bnxt_aux_dev_ids, GFP_KERNEL);
> + if (bp->aux_dev->id < 0) {
> + netdev_warn(bp->dev,
> + "ida alloc failed for ROCE auxiliary device\n");
> + goto skip_aux_init;
> + }
> +
> + /* If aux bus init fails, continue with netdev init. */
> + rc = bnxt_rdma_aux_device_add(bp);
> + if (rc) {
> + netdev_warn(bp->dev,
> + "Failed to add auxiliary device for ROCE\n");
> + goto aux_add_failed;
> + }
> + }
> + return;
> +
> +aux_add_failed:
> + ida_free(&bnxt_aux_dev_ids, bp->aux_dev->id);
> + bp->aux_dev->id = -1;
> +skip_aux_init:
> + bnxt_aux_dev_free(bp);
> +skip_ida_init:
> + bp->flags &= ~BNXT_FLAG_ROCE_CAP;
> +}

> +static inline void bnxt_set_edev_info(struct bnxt_en_dev *edev, struct bnxt *bp)

Please don't use inline for no good reason.

> +{
> + edev->en_ops = &bnxt_en_ops_tbl;
> + edev->net = bp->dev;
> + edev->pdev = bp->pdev;
> + edev->l2_db_size = bp->db_size;
> + edev->l2_db_size_nc = bp->db_size;
> +
> + if (bp->flags & BNXT_FLAG_ROCEV1_CAP)
> + edev->flags |= BNXT_EN_FLAG_ROCEV1_CAP;
> + if (bp->flags & BNXT_FLAG_ROCEV2_CAP)
> + edev->flags |= BNXT_EN_FLAG_ROCEV2_CAP;
> +}
> +
> +int bnxt_rdma_aux_device_add(struct bnxt *bp)
> +{
> + struct bnxt_aux_dev *bnxt_adev = bp->aux_dev;
> + struct bnxt_en_dev *edev = bnxt_adev->edev;
> + struct auxiliary_device *aux_dev;
> + int ret;
> +
> + edev = kzalloc(sizeof(*edev), GFP_KERNEL);
> + if (!edev) {
> + ret = -ENOMEM;
> + goto cleanup_edev_failure;
> + }
> +
> + aux_dev = &bnxt_adev->aux_dev;
> + aux_dev->id = bnxt_adev->id;
> + aux_dev->name = "rdma";
> + aux_dev->dev.parent = &bp->pdev->dev;
> + aux_dev->dev.release = bnxt_aux_dev_release;
> +
> + bnxt_adev->edev = edev;
> + bp->edev = edev;
> + bnxt_set_edev_info(edev, bp);
> +
> + ret = auxiliary_device_init(aux_dev);
> + if (ret)
> + goto cleanup_init_failure;
> +
> + ret = auxiliary_device_add(aux_dev);
> + if (ret)
> + goto cleanup_add_failure;
> +
> + return 0;
> +
> +cleanup_add_failure:

Name your labels after what you clean up, not what failed.

> + auxiliary_device_uninit(aux_dev);
> +cleanup_init_failure:
> + kfree(edev);
> + bp->edev = NULL;
> +cleanup_edev_failure:

Don't jump to the return statement, just return.

> + return ret;
> +}
> +
> struct bnxt_en_dev *bnxt_ulp_probe(struct net_device *dev)
> {
> struct bnxt *bp = netdev_priv(dev);
> diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.h b/drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.h
> index 42b50abc3e91..647147a68554 100644
> --- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.h
> +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.h
> @@ -17,6 +17,7 @@
> #define BNXT_MIN_ROCE_STAT_CTXS 1
>
> struct hwrm_async_event_cmpl;
> +struct bnxt_aux_dev;

This forward declaration is not needed, at least in this patch.

> struct bnxt;
>
> struct bnxt_msix_entry {
> @@ -102,10 +103,14 @@ int bnxt_get_ulp_stat_ctxs(struct bnxt *bp);
> void bnxt_ulp_stop(struct bnxt *bp);
> void bnxt_ulp_start(struct bnxt *bp, int err);
> void bnxt_ulp_sriov_cfg(struct bnxt *bp, int num_vfs);
> -void bnxt_ulp_shutdown(struct bnxt *bp);
> void bnxt_ulp_irq_stop(struct bnxt *bp);
> void bnxt_ulp_irq_restart(struct bnxt *bp, int err);
> void bnxt_ulp_async_events(struct bnxt *bp, struct hwrm_async_event_cmpl *cmpl);
> +void bnxt_aux_dev_release(struct device *dev);
> +int bnxt_rdma_aux_device_add(struct bnxt *bp);

This is only used in bnxt_ulp.c, please remove the declaration and make
it static. Please check other functions for the same problem.

> +void bnxt_rdma_aux_device_uninit(struct bnxt *bp);
> +void bnxt_rdma_aux_device_init(struct bnxt *bp);
> +void bnxt_aux_dev_free(struct bnxt *bp);

Next message: Mark Brown: "Re: [PATCH v2 00/44] VMA tree type safety and remove __vma_adjust()"
Previous message: Vishal Annapurve: "Re: [PATCH v10 3/9] KVM: Extend the memslot to support fd-based private memory"
Next in thread: Ajit Khaparde: "Re: [PATCH 1/8] bnxt_en: Add auxiliary driver support"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]