Re: [dpdk-dev] [PATCH v3] cryptodev: version cryptodev info get function

[Ray Kinsella <mdr@ashroe.eu>]

On 20/04/2020 15:22, Akhil Goyal wrote:
> 
> 
>>
>> This patch adds versioned function rte_cryptodev_info_get()
>> to prevent some issues with ABI policy.
>> Node v21 works in same way as before, returning driver capabilities
>> directly to the API caller. These capabilities may include new elements
>> not part of the v20 ABI.
>> Node v20 function maintains compatibility with v20 ABI releases
>> by stripping out elements not supported in v20 ABI. Because
>> rte_cryptodev_info_get is called by other API functions,
>> rte_cryptodev_sym_capability_get function is versioned the same way.
>>
>> Signed-off-by: Arek Kusztal <arkadiuszx.kusztal@intel.com>
>> ---
>> v2:
>> - changed version numbers of symbols to 20.0.2
>> v3:
>> - added v2/v3 informations
>> - changed version numbers of symbols to 21
>> - fixed checkpatch issues
>>
>> This patch depends on following patches:
>>
>> [1] - "[v3] cryptodev: add chacha20-poly1305 aead algorithm"
>> (https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fpatchwor
>> k.dpdk.org%2Fpatch%2F64549%2F&amp;data=02%7C01%7Cakhil.goyal%40nxp.
>> com%7Ce6789fd42a5946c128e508d7e2dffe2f%7C686ea1d3bc2b4c6fa92cd99c
>> 5c301635%7C0%7C0%7C637227323980059545&amp;sdata=50eQJE7WHTME6d
>> qA7Nfk%2B50PVAyJrpKlMw%2BoGtA1%2FTc%3D&amp;reserved=0)
> 
> Please include the dependent patches in a single series in your next version.
>>
>>  lib/librte_cryptodev/rte_cryptodev.c           | 143 ++++++++++++++++++++++++-
>>  lib/librte_cryptodev/rte_cryptodev.h           |  39 ++++++-
>>  lib/librte_cryptodev/rte_cryptodev_version.map |   7 ++
>>  3 files changed, 186 insertions(+), 3 deletions(-)
>>
>> diff --git a/lib/librte_cryptodev/rte_cryptodev.c
>> b/lib/librte_cryptodev/rte_cryptodev.c
>> index 6d1d0e9..b061447 100644
>> --- a/lib/librte_cryptodev/rte_cryptodev.c
>> +++ b/lib/librte_cryptodev/rte_cryptodev.c
>> @@ -41,6 +41,9 @@
>>  #include "rte_cryptodev.h"
>>  #include "rte_cryptodev_pmd.h"
>>
>> +#include <rte_compat.h>
>> +#include <rte_function_versioning.h>
>> +
>>  static uint8_t nb_drivers;
>>
>>  static struct rte_cryptodev rte_crypto_devices[RTE_CRYPTO_MAX_DEVS];
>> @@ -56,6 +59,14 @@ static struct rte_cryptodev_global cryptodev_globals = {
>>  /* spinlock for crypto device callbacks */
>>  static rte_spinlock_t rte_cryptodev_cb_lock = RTE_SPINLOCK_INITIALIZER;
>>
>> +static const struct rte_cryptodev_capabilities
>> +		cryptodev_undefined_capabilities[] = {
>> +		RTE_CRYPTODEV_END_OF_CAPABILITIES_LIST()
>> +};
>> +
>> +static struct rte_cryptodev_capabilities
>> +		*capability_copies[RTE_CRYPTO_MAX_DEVS];
> 
> Capabilities_copy is a better name as it is copy of many capabilities.
> 
>> +static uint8_t is_capability_checked[RTE_CRYPTO_MAX_DEVS];
>>
>>  /**
>>   * The user application callback description.
>> @@ -280,7 +291,43 @@ rte_crypto_auth_operation_strings[] = {
>>  };
>>
>>  const struct rte_cryptodev_symmetric_capability *
>> -rte_cryptodev_sym_capability_get(uint8_t dev_id,
>> +rte_cryptodev_sym_capability_get_v20(uint8_t dev_id,
> 
> __vsym Annotation to be used in a declaration of the internal symbol
> to signal that it is being used as an implementation of a particular
> version of symbol.
> 
>> +		const struct rte_cryptodev_sym_capability_idx *idx)
>> +{
>> +	const struct rte_cryptodev_capabilities *capability;
>> +	struct rte_cryptodev_info dev_info;
>> +	int i = 0;
>> +
>> +	rte_cryptodev_info_get_v20(dev_id, &dev_info);
>> +
>> +	while ((capability = &dev_info.capabilities[i++])->op !=
>> +			RTE_CRYPTO_OP_TYPE_UNDEFINED) {
>> +		if (capability->op != RTE_CRYPTO_OP_TYPE_SYMMETRIC)
>> +			continue;
>> +
>> +		if (capability->sym.xform_type != idx->type)
>> +			continue;
>> +
>> +		if (idx->type == RTE_CRYPTO_SYM_XFORM_AUTH &&
>> +			capability->sym.auth.algo == idx->algo.auth)
>> +			return &capability->sym;
>> +
>> +		if (idx->type == RTE_CRYPTO_SYM_XFORM_CIPHER &&
>> +			capability->sym.cipher.algo == idx->algo.cipher)
>> +			return &capability->sym;
>> +
>> +		if (idx->type == RTE_CRYPTO_SYM_XFORM_AEAD &&
>> +				capability->sym.aead.algo == idx->algo.aead)
>> +			return &capability->sym;
>> +	}
>> +
>> +	return NULL;
>> +
> 
> Extra line
> 
>> +}
>> +VERSION_SYMBOL(rte_cryptodev_sym_capability_get, _v20, 20.0);
>> +
>> +const struct rte_cryptodev_symmetric_capability *
> 
> __vsym annotation
> 
>> +rte_cryptodev_sym_capability_get_v21(uint8_t dev_id,
>>  		const struct rte_cryptodev_sym_capability_idx *idx)
>>  {
>>  	const struct rte_cryptodev_capabilities *capability;
>> @@ -313,6 +360,10 @@ rte_cryptodev_sym_capability_get(uint8_t dev_id,
>>  	return NULL;
>>
>>  }
>> +MAP_STATIC_SYMBOL(const struct rte_cryptodev_symmetric_capability *
>> +		rte_cryptodev_sym_capability_get(uint8_t dev_id,
>> +		const struct rte_cryptodev_sym_capability_idx *idx),
>> +		rte_cryptodev_sym_capability_get_v21);
>>
>>  static int
>>  param_range_check(uint16_t size, const struct rte_crypto_param_range *range)
>> @@ -999,6 +1050,13 @@ rte_cryptodev_close(uint8_t dev_id)
>>  	RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->dev_close, -ENOTSUP);
>>  	retval = (*dev->dev_ops->dev_close)(dev);
>>
>> +
>> +	if (capability_copies[dev_id]) {
>> +		free(capability_copies[dev_id]);
>> +		capability_copies[dev_id] = NULL;
>> +	}
>> +	is_capability_checked[dev_id] = 0;
>> +
>>  	if (retval < 0)
>>  		return retval;
>>
>> @@ -1111,9 +1169,61 @@ rte_cryptodev_stats_reset(uint8_t dev_id)
>>  	(*dev->dev_ops->stats_reset)(dev);
>>  }
>>
>> +static void
>> +get_v20_capabilities(uint8_t dev_id, struct rte_cryptodev_info *dev_info)
>> +{
>> +	const struct rte_cryptodev_capabilities *capability;
>> +	uint8_t found_invalid_capa = 0;
>> +	uint8_t counter = 0;
>> +
>> +	for (capability = dev_info->capabilities;
>> +			capability->op != RTE_CRYPTO_OP_TYPE_UNDEFINED;
>> +			++capability, ++counter) {
>> +		if (capability->op == RTE_CRYPTO_OP_TYPE_SYMMETRIC &&
>> +				capability->sym.xform_type ==
>> +					RTE_CRYPTO_SYM_XFORM_AEAD
>> +				&& capability->sym.aead.algo >=
>> +				RTE_CRYPTO_AEAD_CHACHA20_POLY1305) {
>> +			found_invalid_capa = 1;
>> +			counter--;
>> +		}
>> +	}
>> +	is_capability_checked[dev_id] = 1;
>> +	if (found_invalid_capa) {
> 
> Code becomes unreadable due to indentation which can be avoided.
> 
> if (!found_invalid_capa)
> 	return;
> capability_copies[dev_id] = malloc(counter * sizeof(struct rte_cryptodev_capabilities));
> if (capability_copies[dev_id] == NULL) {
> 	dev_info->capabilities = cryptodev_undefined_capabilities;
> 	is_capability_checked[dev_id] = 0;
> 	return;
> }
> 
> counter = 0;
> for(...) {
> ...
> }
>> +		capability_copies[dev_id] = malloc(counter *
>> +			sizeof(struct rte_cryptodev_capabilities));
>> +		if (capability_copies[dev_id] == NULL) {
>> +			 /*
>> +			  * error case - no memory to store the trimmed
>> +			  * list, so have to return an empty list
>> +			  */
>> +			dev_info->capabilities =
>> +				cryptodev_undefined_capabilities;
>> +			is_capability_checked[dev_id] = 0;
>> +		} else {
>> +			counter = 0;
>> +			for (capability = dev_info->capabilities;
>> +					capability->op !=
>> +					RTE_CRYPTO_OP_TYPE_UNDEFINED;
>> +					capability++) {
>> +				if (!(capability->op ==
>> +					RTE_CRYPTO_OP_TYPE_SYMMETRIC
>> +					&& capability->sym.xform_type ==
>> +					RTE_CRYPTO_SYM_XFORM_AEAD
>> +					&& capability->sym.aead.algo >=
>> +
>> 	RTE_CRYPTO_AEAD_CHACHA20_POLY1305)) {
>> +					capability_copies[dev_id][counter++] =
>> +							*capability;
>> +				}
>> +			}
>> +			dev_info->capabilities =
>> +					capability_copies[dev_id];
>> +		}
>> +	}
>> +}
>>
>>  void
>> -rte_cryptodev_info_get(uint8_t dev_id, struct rte_cryptodev_info *dev_info)
>> +rte_cryptodev_info_get_v20(uint8_t dev_id, struct rte_cryptodev_info
>> *dev_info)
>>  {
>>  	struct rte_cryptodev *dev;
>>
>> @@ -1129,10 +1239,39 @@ rte_cryptodev_info_get(uint8_t dev_id, struct
>> rte_cryptodev_info *dev_info)
>>  	RTE_FUNC_PTR_OR_RET(*dev->dev_ops->dev_infos_get);
>>  	(*dev->dev_ops->dev_infos_get)(dev, dev_info);
>>
>> +	if (capability_copies[dev_id] == NULL) {
>> +		if (!is_capability_checked[dev_id])
>> +			get_v20_capabilities(dev_id, dev_info);
>> +	} else
>> +		dev_info->capabilities = capability_copies[dev_id];
>> +
>>  	dev_info->driver_name = dev->device->driver->name;
>>  	dev_info->device = dev->device;
>>  }
>> +VERSION_SYMBOL(rte_cryptodev_info_get, _v20, 20.0);
>> +
>> +void
>> +rte_cryptodev_info_get_v21(uint8_t dev_id, struct rte_cryptodev_info
>> *dev_info)
>> +{
>> +	struct rte_cryptodev *dev;
>> +
>> +	if (!rte_cryptodev_pmd_is_valid_dev(dev_id)) {
>> +		CDEV_LOG_ERR("Invalid dev_id=%d", dev_id);
>> +		return;
>> +	}
>> +
>> +	dev = &rte_crypto_devices[dev_id];
>>
>> +	memset(dev_info, 0, sizeof(struct rte_cryptodev_info));
>> +
>> +	RTE_FUNC_PTR_OR_RET(*dev->dev_ops->dev_infos_get);
>> +	(*dev->dev_ops->dev_infos_get)(dev, dev_info);
>> +
>> +	dev_info->driver_name = dev->device->driver->name;
>> +	dev_info->device = dev->device;
>> +}
>> +MAP_STATIC_SYMBOL(void rte_cryptodev_info_get(uint8_t dev_id,
>> +	struct rte_cryptodev_info *dev_info), rte_cryptodev_info_get_v21);
>>
>>  int
>>  rte_cryptodev_callback_register(uint8_t dev_id,
>> diff --git a/lib/librte_cryptodev/rte_cryptodev.h
>> b/lib/librte_cryptodev/rte_cryptodev.h
>> index 437b8a9..7f1bc90 100644
>> --- a/lib/librte_cryptodev/rte_cryptodev.h
>> +++ b/lib/librte_cryptodev/rte_cryptodev.h
>> @@ -24,6 +24,9 @@ extern "C" {
>>  #include <rte_common.h>
>>  #include <rte_config.h>
>>
>> +#include <rte_compat.h>
>> +#include <rte_function_versioning.h>
>> +
>>  extern const char **rte_cyptodev_names;
>>
>>  /* Logging Macros */
>> @@ -217,6 +220,15 @@ struct rte_cryptodev_asym_capability_idx {
>>   *   - Return NULL if the capability not exist.
>>   */
>>  const struct rte_cryptodev_symmetric_capability *
>> +rte_cryptodev_sym_capability_get_v20(uint8_t dev_id,
>> +		const struct rte_cryptodev_sym_capability_idx *idx);
>> +
>> +const struct rte_cryptodev_symmetric_capability *
>> +rte_cryptodev_sym_capability_get_v21(uint8_t dev_id,
>> +		const struct rte_cryptodev_sym_capability_idx *idx);
>> +BIND_DEFAULT_SYMBOL(rte_cryptodev_sym_capability_get, _v21, 21);
>> +
>> +const struct rte_cryptodev_symmetric_capability *
>>  rte_cryptodev_sym_capability_get(uint8_t dev_id,
>>  		const struct rte_cryptodev_sym_capability_idx *idx);
>>
>> @@ -758,9 +770,34 @@ rte_cryptodev_stats_reset(uint8_t dev_id);
>>   * the last valid element has it's op field set to
>>   * RTE_CRYPTO_OP_TYPE_UNDEFINED.
>>   */
>> -extern void
>> +
>> +void
>>  rte_cryptodev_info_get(uint8_t dev_id, struct rte_cryptodev_info *dev_info);
>>
>> +/* An extra element RTE_CRYPTO_AEAD_CHACHA20_POLY1305 is added
>> + * to enum rte_crypto_aead_algorithm, also changing the value of
>> + *  RTE_CRYPTO_AEAD_LIST_END. To maintain ABI compatibility with
>> applications
>> + * which linked against earlier versions, preventing them, for example, from
>> + * picking up the new value and using it to index into an array sized too small
>> + * for it, it is necessary to have two versions of rte_cryptodev_info_get()
>> + * The latest version just returns directly the capabilities retrieved from
>> + * the device. The compatible version inspects the capabilities retrieved
>> + * from the device, but only returns them directly if the new value
>> + * is not included. If the new value is included, it allocates space
>> + * for a copy of the device capabilities, trims the new value from this
>> + * and returns this copy. It only needs to do this once per device.
>> + * For the corner case of a corner case when the alloc may fail,
>> + * an empty capability list is returned, as there is no mechanism to return
>> + * an error and adding such a mechanism would itself be an ABI breakage.
>> + * The compatible version can be removed after the next major ABI release.
>> + */
>> +
>> +void
>> +rte_cryptodev_info_get_v20(uint8_t dev_id, struct rte_cryptodev_info
>> *dev_info);
>> +
>> +void
>> +rte_cryptodev_info_get_v21(uint8_t dev_id, struct rte_cryptodev_info
>> *dev_info);
>> +BIND_DEFAULT_SYMBOL(rte_cryptodev_info_get, _v21, 21);
> 
> I am not sure if we need to bind for _v20 also
> BIND_DEFAULT_SYMBOL(rte_cryptodev_info_get, _v20, 20);

The correct call to VERSION_SYMBOL is already above.

> 
> Ray, can you please suggest if it required or not? And what all we need to check?

See below. 

> 
> The patch is still showing Incompatibilities
> NOTICE: ABI may be incompatible, check reports/logs for details.
> NOTICE: Incompatible list:  librte_cryptodev.so

So I looked through the issues it is complaining about, these are here.
https://travis-ci.com/github/ovsrobot/dpdk/jobs/320526253#L4540

Basically they all are warnings related to the changes to the enumeration  rte_crypto_aead_algorithm.

Essentially the new member RTE_CRYPTO_AEAD_CHACHA20_POLY1305.
The change to the end value RTE_CRYPTO_AEAD_LIST_END.
Members of this type "enum rte_crypto_aead_algorithm algo" are demeeded to also have changed, but they haven't.

With the additional work to create the v20 version of rte_cryptodev_info_get.
I think all reasonable steps have been been taken here. 

> 
>>
>>  /**
>>   * Register a callback function for specific device id.
>> diff --git a/lib/librte_cryptodev/rte_cryptodev_version.map
>> b/lib/librte_cryptodev/rte_cryptodev_version.map
>> index 6e41b4b..512a4a7 100644
>> --- a/lib/librte_cryptodev/rte_cryptodev_version.map
>> +++ b/lib/librte_cryptodev/rte_cryptodev_version.map
>> @@ -58,6 +58,13 @@ DPDK_20.0 {
>>  	local: *;
>>  };
>>
>> +DPDK_21 {

Should be DPDK_21.0

>> +	global:
>> +	rte_cryptodev_info_get;
>> +	rte_cryptodev_sym_capability_get;
>> +} DPDK_20.0;
>> +
>> +
>>  EXPERIMENTAL {
>>  	global:
>>
>> --
>> 2.1.0
>