Commit 1517f63c authored by Andrey Smirnov's avatar Andrey Smirnov Committed by Herbert Xu
Browse files

crypto: caam - drop global context pointer and init_done 



Leverage devres to get rid of code storing global context as well as
init_done flag.

Original code also has a circular deallocation dependency where
unregister_algs() -> caam_rng_exit() -> caam_jr_free() chain would
only happen if all of JRs were freed. Fix this by moving
caam_rng_exit() outside of unregister_algs() and doing it specifically
for JR that instantiated HWRNG.

Signed-off-by: default avatarAndrey Smirnov <andrew.smirnov@gmail.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Horia Geantă <horia.geanta@nxp.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Iuliana Prodan <iuliana.prodan@nxp.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-imx@nxp.com
Reviewed-by: default avatarHoria Geantă <horia.geanta@nxp.com>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent 8483c831

drivers/crypto/caam/caamrng.c

+33 −34
Original line number Diff line number Diff line
@@ -70,6 +70,7 @@ struct buf_data { 


/* rng per-device context */

struct caam_rng_ctx {

	struct hwrng rng;

	struct device *jrdev;

	dma_addr_t sh_desc_dma;

	u32 sh_desc[DESC_RNG_LEN];
@@ -78,13 +79,10 @@ struct caam_rng_ctx { 
	struct buf_data bufs[2];

};



static struct caam_rng_ctx *rng_ctx;



/*

 * Variable used to avoid double free of resources in case

 * algorithm registration was unsuccessful

 */

static bool init_done;

static struct caam_rng_ctx *to_caam_rng_ctx(struct hwrng *r)

{

	return (struct caam_rng_ctx *)r->priv;

}



static inline void rng_unmap_buf(struct device *jrdev, struct buf_data *bd)

{
@@ -143,7 +141,7 @@ static inline int submit_job(struct caam_rng_ctx *ctx, int to_current) 


static int caam_read(struct hwrng *rng, void *data, size_t max, bool wait)

{

	struct caam_rng_ctx *ctx = rng_ctx;

	struct caam_rng_ctx *ctx = to_caam_rng_ctx(rng);

	struct buf_data *bd = &ctx->bufs[ctx->current_buf];

	int next_buf_idx, copied_idx;

	int err;
@@ -246,17 +244,18 @@ static inline int rng_create_job_desc(struct caam_rng_ctx *ctx, int buf_id) 


static void caam_cleanup(struct hwrng *rng)

{

	struct caam_rng_ctx *ctx = to_caam_rng_ctx(rng);

	int i;

	struct buf_data *bd;



	for (i = 0; i < 2; i++) {

		bd = &rng_ctx->bufs[i];

		bd = &ctx->bufs[i];

		if (atomic_read(&bd->empty) == BUF_PENDING)

			wait_for_completion(&bd->filled);

	}



	rng_unmap_ctx(rng_ctx);

	caam_jr_free(rng_ctx->jrdev);

	rng_unmap_ctx(ctx);

	caam_jr_free(ctx->jrdev);

}



static int caam_init_buf(struct caam_rng_ctx *ctx, int buf_id)
@@ -277,7 +276,7 @@ static int caam_init_buf(struct caam_rng_ctx *ctx, int buf_id) 


static int caam_init(struct hwrng *rng)

{

	struct caam_rng_ctx *ctx = rng_ctx;

	struct caam_rng_ctx *ctx = to_caam_rng_ctx(rng);

	int err;



	ctx->jrdev = caam_jr_alloc();
@@ -309,28 +308,19 @@ free_jrdev: 
	return err;

}



static struct hwrng caam_rng = {

	.name		= "rng-caam",

	.init           = caam_init,

	.cleanup	= caam_cleanup,

	.read		= caam_read,

};

int caam_rng_init(struct device *ctrldev);



void caam_rng_exit(void)

void caam_rng_exit(struct device *ctrldev)

{

	if (!init_done)

		return;



	hwrng_unregister(&caam_rng);

	kfree(rng_ctx);

	devres_release_group(ctrldev, caam_rng_init);

}



int caam_rng_init(struct device *ctrldev)

{

	struct caam_rng_ctx *ctx;

	u32 rng_inst;

	struct caam_drv_private *priv = dev_get_drvdata(ctrldev);

	int err;

	init_done = false;

	int ret;



	/* Check for an instantiated RNG before registration */

	if (priv->era < 10)
@@ -342,18 +332,27 @@ int caam_rng_init(struct device *ctrldev) 
	if (!rng_inst)

		return 0;



	rng_ctx = kmalloc(sizeof(*rng_ctx), GFP_DMA | GFP_KERNEL);

	if (!rng_ctx)

	if (!devres_open_group(ctrldev, caam_rng_init, GFP_KERNEL))

		return -ENOMEM;



	ctx = devm_kzalloc(ctrldev, sizeof(*ctx), GFP_DMA | GFP_KERNEL);

	if (!ctx)

		return -ENOMEM;



	ctx->rng.name    = "rng-caam";

	ctx->rng.init    = caam_init;

	ctx->rng.cleanup = caam_cleanup;

	ctx->rng.read    = caam_read;

	ctx->rng.priv    = (unsigned long)ctx;



	dev_info(ctrldev, "registering rng-caam\n");



	err = hwrng_register(&caam_rng);

	if (!err) {

		init_done = true;

		return err;

	ret = devm_hwrng_register(ctrldev, &ctx->rng);

	if (ret) {

		caam_rng_exit(ctrldev);

		return ret;

	}



	kfree(rng_ctx);

	return err;

	devres_close_group(ctrldev, caam_rng_init);

	return 0;

}

drivers/crypto/caam/intern.h

+3 −4
Original line number Diff line number Diff line
@@ -47,6 +47,7 @@ struct caam_drv_private_jr { 
	struct caam_job_ring __iomem *rregs;	/* JobR's register space */

	struct tasklet_struct irqtask;

	int irq;			/* One per queue */

	bool hwrng;



	/* Number of scatterlist crypt transforms active on the JobR */

	atomic_t tfm_count ____cacheline_aligned;
@@ -163,7 +164,7 @@ static inline void caam_pkc_exit(void) 
#ifdef CONFIG_CRYPTO_DEV_FSL_CAAM_RNG_API



int caam_rng_init(struct device *dev);

void caam_rng_exit(void);

void caam_rng_exit(struct device *dev);



#else
@@ -172,9 +173,7 @@ static inline int caam_rng_init(struct device *dev) 
	return 0;

}



static inline void caam_rng_exit(void)

{

}

static inline void caam_rng_exit(struct device *dev) {}



#endif /* CONFIG_CRYPTO_DEV_FSL_CAAM_RNG_API */

drivers/crypto/caam/jr.c

+8 −5
Original line number Diff line number Diff line
@@ -27,7 +27,8 @@ static struct jr_driver_data driver_data; 
static DEFINE_MUTEX(algs_lock);

static unsigned int active_devs;



static void register_algs(struct device *dev)

static void register_algs(struct caam_drv_private_jr *jrpriv,

			  struct device *dev)

{

	mutex_lock(&algs_lock);
@@ -37,7 +38,7 @@ static void register_algs(struct device *dev) 
	caam_algapi_init(dev);

	caam_algapi_hash_init(dev);

	caam_pkc_init(dev);

	caam_rng_init(dev);

	jrpriv->hwrng = !caam_rng_init(dev);

	caam_qi_algapi_init(dev);



algs_unlock:
@@ -53,7 +54,6 @@ static void unregister_algs(void) 


	caam_qi_algapi_exit();



	caam_rng_exit();

	caam_pkc_exit();

	caam_algapi_hash_exit();

	caam_algapi_exit();
@@ -135,6 +135,9 @@ static int caam_jr_remove(struct platform_device *pdev) 
	jrdev = &pdev->dev;

	jrpriv = dev_get_drvdata(jrdev);



	if (jrpriv->hwrng)

		caam_rng_exit(jrdev->parent);



	/*

	 * Return EBUSY if job ring already allocated.

	 */
@@ -514,7 +517,7 @@ static int caam_jr_probe(struct platform_device *pdev) 
	int error;



	jrdev = &pdev->dev;

	jrpriv = devm_kmalloc(jrdev, sizeof(*jrpriv), GFP_KERNEL);

	jrpriv = devm_kzalloc(jrdev, sizeof(*jrpriv), GFP_KERNEL);

	if (!jrpriv)

		return -ENOMEM;
@@ -590,7 +593,7 @@ static int caam_jr_probe(struct platform_device *pdev) 


	atomic_set(&jrpriv->tfm_count, 0);



	register_algs(jrdev->parent);

	register_algs(jrpriv, jrdev->parent);



	return 0;

}

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