[PATCH 3/4] crypto: caam: Unembed net_dev structure from qi

Breno Leitao
2024-06-24T16:22:32Z

Embedding net_device into structures prohibits the usage of flexible
arrays in the net_device structure. For more details, see the discussion
at [1].

Un-embed the net_devices from struct caam_qi_pcpu_priv by converting them
into pointers, and allocating them dynamically. Use the leverage
alloc_netdev_dummy() to allocate the net_device object at
caam_qi_init().

The free of the device occurs at caam_qi_shutdown().

Link: https://lore.kernel.org/all/20240229225910.79e224cf@kernel.org/ [1]
Signed-off-by: Breno Leitao <leitao@debian.org>
---
PS: Unfortunately due to lack of hardware, this was not tested in real
hardware.

drivers/crypto/caam/qi.c | 43 ++++++++++++++++++++++++++++++++--------
1 file changed, 35 insertions(+), 8 deletions(-)

diff --git a/drivers/crypto/caam/qi.c b/drivers/crypto/caam/qi.c
index 46a083849a8e..0c13ffc81862 100644
--- a/drivers/crypto/caam/qi.c
+++ b/drivers/crypto/caam/qi.c
@@ -57,7 +57,7 @@ struct caam_napi {
*/
struct caam_qi_pcpu_priv {
struct caam_napi caam_napi;
- struct net_device net_dev;
+ struct net_device *net_dev;
struct qman_fq *rsp_fq;
} ____cacheline_aligned;

@@ -144,7 +144,7 @@ static void caam_fq_ern_cb(struct qman_portal *qm, struct qman_fq *fq,
{
const struct qm_fd *fd;
struct caam_drv_req *drv_req;
- struct device *qidev = &(raw_cpu_ptr(&pcpu_qipriv)->net_dev.dev);
+ struct device *qidev = &(raw_cpu_ptr(&pcpu_qipriv)->net_dev->dev);
struct caam_drv_private *priv = dev_get_drvdata(qidev);

fd = &msg->ern.fd;
@@ -530,6 +530,7 @@ static void caam_qi_shutdown(void *data)

if (kill_fq(qidev, per_cpu(pcpu_qipriv.rsp_fq, i)))
dev_err(qidev, "Rsp FQ kill failed, cpu: %d\n", i);
+ free_netdev(pcpu_qipriv.net_dev);
}

qman_delete_cgr_safe(&priv->cgr);
@@ -573,7 +574,7 @@ static enum qman_cb_dqrr_result caam_rsp_fq_dqrr_cb(struct qman_portal *p,
struct caam_napi *caam_napi = raw_cpu_ptr(&pcpu_qipriv.caam_napi);
struct caam_drv_req *drv_req;
const struct qm_fd *fd;
- struct device *qidev = &(raw_cpu_ptr(&pcpu_qipriv)->net_dev.dev);
+ struct device *qidev = &(raw_cpu_ptr(&pcpu_qipriv)->net_dev->dev);
struct caam_drv_private *priv = dev_get_drvdata(qidev);
u32 status;

@@ -718,12 +719,24 @@ static void free_rsp_fqs(void)
kfree(per_cpu(pcpu_qipriv.rsp_fq, i));
}

+static void free_caam_qi_pcpu_netdev(const cpumask_t *cpus)
+{
+ struct caam_qi_pcpu_priv *priv;
+ int i;
+
+ for_each_cpu(i, cpus) {
+ priv = per_cpu_ptr(&pcpu_qipriv, i);
+ free_netdev(priv->net_dev);
+ }
+}
+
int caam_qi_init(struct platform_device *caam_pdev)
{
int err, i;
struct device *ctrldev = &caam_pdev->dev, *qidev;
struct caam_drv_private *ctrlpriv;
const cpumask_t *cpus = qman_affine_cpus();
+ cpumask_t clean_mask;

ctrlpriv = dev_get_drvdata(ctrldev);
qidev = ctrldev;
@@ -743,6 +756,8 @@ int caam_qi_init(struct platform_device *caam_pdev)
return err;
}

+ cpumask_clear(&clean_mask);
+
/*
* Enable the NAPI contexts on each of the core which has an affine
* portal.
@@ -751,10 +766,16 @@ int caam_qi_init(struct platform_device *caam_pdev)
struct caam_qi_pcpu_priv *priv = per_cpu_ptr(&pcpu_qipriv, i);
struct caam_napi *caam_napi = &priv->caam_napi;
struct napi_struct *irqtask = &caam_napi->irqtask;
- struct net_device *net_dev = &priv->net_dev;
+ struct net_device *net_dev;

+ net_dev = alloc_netdev_dummy(0);
+ if (!net_dev) {
+ err = -ENOMEM;
+ goto fail;
+ }
+ cpumask_set_cpu(i, &clean_mask);
+ priv->net_dev = net_dev;
net_dev->dev = *qidev;
- INIT_LIST_HEAD(&net_dev->napi_list);

netif_napi_add_tx_weight(net_dev, irqtask, caam_qi_poll,
CAAM_NAPI_WEIGHT);
@@ -766,16 +787,22 @@ int caam_qi_init(struct platform_device *caam_pdev)
dma_get_cache_alignment(), 0, NULL);
if (!qi_cache) {
dev_err(qidev, "Can't allocate CAAM cache\n");
- free_rsp_fqs();
- return -ENOMEM;
+ err = -ENOMEM;
+ goto fail2;
}

caam_debugfs_qi_init(ctrlpriv);

err = devm_add_action_or_reset(qidev, caam_qi_shutdown, ctrlpriv);
if (err)
- return err;
+ goto fail2;

dev_info(qidev, "Linux CAAM Queue I/F driver initialised\n");
return 0;
+
+fail2:
+ free_rsp_fqs();
+fail:
+ free_caam_qi_pcpu_netdev(&clean_mask);
+ return err;
}
--
2.43.0