Commit 29e83c75 authored by Horia Geantă's avatar Horia Geantă Committed by Herbert Xu
Browse files

crypto: caam/qi - simplify CGR allocation, freeing 

CGRs (Congestion Groups) have to be freed by the same CPU that
initialized them.
This is why currently the driver takes special measures; however, using
set_cpus_allowed_ptr() is incorrect - as reported by Sebastian.

Instead of the generic solution of replacing set_cpus_allowed_ptr() with
work_on_cpu_safe(), we use the qman_delete_cgr_safe() QBMan API instead
of qman_delete_cgr() - which internally takes care of proper CGR
deletion.

Link: https://lkml.kernel.org/r/20181005125443.dfhd2asqktm22ney@linutronix.de


Reported-by: default avatarSebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: default avatarHoria Geantă <horia.geanta@nxp.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 58c8a863

drivers/crypto/caam/qi.c

+4 −39
Original line number Diff line number Diff line
@@ -83,13 +83,6 @@ EXPORT_SYMBOL(caam_congested); 
static u64 times_congested;

#endif



/*

 * CPU from where the module initialised. This is required because QMan driver

 * requires CGRs to be removed from same CPU from where they were originally

 * allocated.

 */

static int mod_init_cpu;



/*

 * This is a a cache of buffers, from which the users of CAAM QI driver

 * can allocate short (CAAM_QI_MEMCACHE_SIZE) buffers. It's faster than
@@ -492,12 +485,11 @@ void caam_drv_ctx_rel(struct caam_drv_ctx *drv_ctx) 
}

EXPORT_SYMBOL(caam_drv_ctx_rel);



int caam_qi_shutdown(struct device *qidev)

void caam_qi_shutdown(struct device *qidev)

{

	int i, ret;

	int i;

	struct caam_qi_priv *priv = dev_get_drvdata(qidev);

	const cpumask_t *cpus = qman_affine_cpus();

	struct cpumask old_cpumask = current->cpus_allowed;



	for_each_cpu(i, cpus) {

		struct napi_struct *irqtask;
@@ -510,26 +502,12 @@ int caam_qi_shutdown(struct device *qidev) 
			dev_err(qidev, "Rsp FQ kill failed, cpu: %d\n", i);

	}



	/*

	 * QMan driver requires CGRs to be deleted from same CPU from where they

	 * were instantiated. Hence we get the module removal execute from the

	 * same CPU from where it was originally inserted.

	 */

	set_cpus_allowed_ptr(current, get_cpu_mask(mod_init_cpu));



	ret = qman_delete_cgr(&priv->cgr);

	if (ret)

		dev_err(qidev, "Deletion of CGR failed: %d\n", ret);

	else

	qman_delete_cgr_safe(&priv->cgr);

	qman_release_cgrid(priv->cgr.cgrid);



	kmem_cache_destroy(qi_cache);



	/* Now that we're done with the CGRs, restore the cpus allowed mask */

	set_cpus_allowed_ptr(current, &old_cpumask);



	platform_device_unregister(priv->qi_pdev);

	return ret;

}



static void cgr_cb(struct qman_portal *qm, struct qman_cgr *cgr, int congested)
@@ -718,22 +696,11 @@ int caam_qi_init(struct platform_device *caam_pdev) 
	struct device *ctrldev = &caam_pdev->dev, *qidev;

	struct caam_drv_private *ctrlpriv;

	const cpumask_t *cpus = qman_affine_cpus();

	struct cpumask old_cpumask = current->cpus_allowed;

	static struct platform_device_info qi_pdev_info = {

		.name = "caam_qi",

		.id = PLATFORM_DEVID_NONE

	};



	/*

	 * QMAN requires CGRs to be removed from same CPU+portal from where it

	 * was originally allocated. Hence we need to note down the

	 * initialisation CPU and use the same CPU for module exit.

	 * We select the first CPU to from the list of portal owning CPUs.

	 * Then we pin module init to this CPU.

	 */

	mod_init_cpu = cpumask_first(cpus);

	set_cpus_allowed_ptr(current, get_cpu_mask(mod_init_cpu));



	qi_pdev_info.parent = ctrldev;

	qi_pdev_info.dma_mask = dma_get_mask(ctrldev);

	qi_pdev = platform_device_register_full(&qi_pdev_info);
@@ -795,8 +762,6 @@ int caam_qi_init(struct platform_device *caam_pdev) 
		return -ENOMEM;

	}



	/* Done with the CGRs; restore the cpus allowed mask */

	set_cpus_allowed_ptr(current, &old_cpumask);

#ifdef CONFIG_DEBUG_FS

	debugfs_create_file("qi_congested", 0444, ctrlpriv->ctl,

			    &times_congested, &caam_fops_u64_ro);

drivers/crypto/caam/qi.h

+1 −1
Original line number Diff line number Diff line
@@ -173,7 +173,7 @@ int caam_drv_ctx_update(struct caam_drv_ctx *drv_ctx, u32 *sh_desc); 
void caam_drv_ctx_rel(struct caam_drv_ctx *drv_ctx);



int caam_qi_init(struct platform_device *pdev);

int caam_qi_shutdown(struct device *dev);

void caam_qi_shutdown(struct device *dev);



/**

 * qi_cache_alloc - Allocate buffers from CAAM-QI cache

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