[dpdk-dev] [PATCH] cryptodev: fix invalid dev_id after a pmd close

[Julien Meunier <julien.meunier@nokia.com>]

Each cryptodev are indexed with its dev_id in the global
rte_crypto_devices variable. nb_devs is incremented / decremented each
time a cryptodev is created / deleted. The goal of nb_devs is to prevent
the user to get an invalid dev_id.

Let's imagine DPDK has configured N cryptodevs. If the cryptodev=1 is
removed at runtime, the latest cryptodev N cannot be accessible, because
nb_devs=N-1.

In order to prevent this kind of behavior, let's remove the check with
nb_devs and iterate in all the rte_crypto_devices elements: if data is
not NULL, that means a valid cryptodev is available.

Fixes: d11b0f30df88 ("cryptodev: introduce API and framework for crypto devices")
Cc: stable@dpdk.org

Signed-off-by: Julien Meunier <julien.meunier@nokia.com>
---
 lib/librte_cryptodev/rte_cryptodev.c | 42 ++++++++++++++++++++++++------------
 1 file changed, 28 insertions(+), 14 deletions(-)

diff --git a/lib/librte_cryptodev/rte_cryptodev.c b/lib/librte_cryptodev/rte_cryptodev.c
index 43bc335..c8c7ffd 100644
--- a/lib/librte_cryptodev/rte_cryptodev.c
+++ b/lib/librte_cryptodev/rte_cryptodev.c
@@ -49,9 +49,7 @@ struct rte_cryptodev *rte_cryptodevs = rte_crypto_devices;
 
 static struct rte_cryptodev_global cryptodev_globals = {
 		.devs			= rte_crypto_devices,
-		.data			= { NULL },
-		.nb_devs		= 0,
-		.max_devs		= RTE_CRYPTO_MAX_DEVS
+		.data			= { NULL }
 };
 
 /* spinlock for crypto device callbacks */
@@ -512,7 +510,7 @@ rte_cryptodev_pmd_get_named_dev(const char *name)
 	if (name == NULL)
 		return NULL;
 
-	for (i = 0; i < cryptodev_globals.max_devs; i++) {
+	for (i = 0; i < RTE_CRYPTO_MAX_DEVS; i++) {
 		dev = &cryptodev_globals.devs[i];
 
 		if ((dev->attached == RTE_CRYPTODEV_ATTACHED) &&
@@ -523,12 +521,21 @@ rte_cryptodev_pmd_get_named_dev(const char *name)
 	return NULL;
 }
 
+static uint8_t
+rte_cryptodev_is_valid_device_data(uint8_t dev_id)
+{
+	if (rte_crypto_devices[dev_id].data == NULL)
+		return 0;
+
+	return 1;
+}
+
 unsigned int
 rte_cryptodev_pmd_is_valid_dev(uint8_t dev_id)
 {
 	struct rte_cryptodev *dev = NULL;
 
-	if (dev_id >= cryptodev_globals.nb_devs)
+	if (!rte_cryptodev_is_valid_device_data(dev_id))
 		return 0;
 
 	dev = rte_cryptodev_pmd_get_dev(dev_id);
@@ -547,12 +554,15 @@ rte_cryptodev_get_dev_id(const char *name)
 	if (name == NULL)
 		return -1;
 
-	for (i = 0; i < cryptodev_globals.nb_devs; i++)
+	for (i = 0; i < RTE_CRYPTO_MAX_DEVS; i++) {
+		if (!rte_cryptodev_is_valid_device_data(i))
+			continue;
 		if ((strcmp(cryptodev_globals.devs[i].data->name, name)
 				== 0) &&
 				(cryptodev_globals.devs[i].attached ==
 						RTE_CRYPTODEV_ATTACHED))
 			return i;
+	}
 
 	return -1;
 }
@@ -560,7 +570,13 @@ rte_cryptodev_get_dev_id(const char *name)
 uint8_t
 rte_cryptodev_count(void)
 {
-	return cryptodev_globals.nb_devs;
+	uint8_t i, dev_count = 0;
+
+	for (i = 0; i < RTE_CRYPTO_MAX_DEVS; i++)
+		if (cryptodev_globals.devs[i].data != NULL)
+			dev_count++;
+
+	return dev_count;
 }
 
 uint8_t
@@ -568,7 +584,7 @@ rte_cryptodev_device_count_by_driver(uint8_t driver_id)
 {
 	uint8_t i, dev_count = 0;
 
-	for (i = 0; i < cryptodev_globals.max_devs; i++)
+	for (i = 0; i < RTE_CRYPTO_MAX_DEVS; i++)
 		if (cryptodev_globals.devs[i].driver_id == driver_id &&
 			cryptodev_globals.devs[i].attached ==
 					RTE_CRYPTODEV_ATTACHED)
@@ -583,9 +599,10 @@ rte_cryptodev_devices_get(const char *driver_name, uint8_t *devices,
 {
 	uint8_t i, count = 0;
 	struct rte_cryptodev *devs = cryptodev_globals.devs;
-	uint8_t max_devs = cryptodev_globals.max_devs;
 
-	for (i = 0; i < max_devs && count < nb_devices;	i++) {
+	for (i = 0; i < RTE_CRYPTO_MAX_DEVS && count < nb_devices; i++) {
+		if (!rte_cryptodev_is_valid_device_data(i))
+			continue;
 
 		if (devs[i].attached == RTE_CRYPTODEV_ATTACHED) {
 			int cmp;
@@ -736,8 +753,6 @@ rte_cryptodev_pmd_allocate(const char *name, int socket_id)
 		TAILQ_INIT(&(cryptodev->link_intr_cbs));
 
 		cryptodev->attached = RTE_CRYPTODEV_ATTACHED;
-
-		cryptodev_globals.nb_devs++;
 	}
 
 	return cryptodev;
@@ -766,7 +781,6 @@ rte_cryptodev_pmd_release_device(struct rte_cryptodev *cryptodev)
 		return ret;
 
 	cryptodev->attached = RTE_CRYPTODEV_DETACHED;
-	cryptodev_globals.nb_devs--;
 	return 0;
 }
 
@@ -1099,7 +1113,7 @@ rte_cryptodev_info_get(uint8_t dev_id, struct rte_cryptodev_info *dev_info)
 {
 	struct rte_cryptodev *dev;
 
-	if (dev_id >= cryptodev_globals.nb_devs) {
+	if (!rte_cryptodev_pmd_is_valid_dev(dev_id)) {
 		CDEV_LOG_ERR("Invalid dev_id=%d", dev_id);
 		return;
 	}
-- 
2.10.2