Re: [PATCH v7 6/9] ethdev: add common devargs parser

["Ananyev, Konstantin" <konstantin.ananyev@intel.com>]

> Introduces a new structure, rte_eth_devargs, to support generic
> ethdev arguments common across NET PMDs, with a new API
> rte_eth_devargs_parse API to support PMD parsing these arguments.
> 
> Signed-off-by: Remy Horton <remy.horton@intel.com>
> Signed-off-by: Declan Doherty <declan.doherty@intel.com>
> ---
>  lib/Makefile                            |   1 +
>  lib/librte_ether/rte_ethdev.c           | 195 ++++++++++++++++++++++++++++++++
>  lib/librte_ether/rte_ethdev_driver.h    |  30 +++++
>  lib/librte_ether/rte_ethdev_version.map |   1 +
>  4 files changed, 227 insertions(+)
> 
> diff --git a/lib/Makefile b/lib/Makefile
> index ec965a606..4144d99f9 100644
> --- a/lib/Makefile
> +++ b/lib/Makefile
> @@ -21,6 +21,7 @@ DEPDIRS-librte_cmdline := librte_eal
>  DIRS-$(CONFIG_RTE_LIBRTE_ETHER) += librte_ether
>  DEPDIRS-librte_ether := librte_net librte_eal librte_mempool librte_ring
>  DEPDIRS-librte_ether += librte_mbuf
> +DEPDIRS-librte_ether += librte_kvargs
>  DIRS-$(CONFIG_RTE_LIBRTE_BBDEV) += librte_bbdev
>  DEPDIRS-librte_bbdev := librte_eal librte_mempool librte_mbuf
>  DIRS-$(CONFIG_RTE_LIBRTE_CRYPTODEV) += librte_cryptodev
> diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c
> index 1d38d8e75..a082b211c 100644
> --- a/lib/librte_ether/rte_ethdev.c
> +++ b/lib/librte_ether/rte_ethdev.c
> @@ -34,6 +34,7 @@
>  #include <rte_errno.h>
>  #include <rte_spinlock.h>
>  #include <rte_string_fns.h>
> ++#include <rte_kvargs.h>
> 
>  #include "rte_ether.h"
>  #include "rte_ethdev.h"
> @@ -4149,6 +4150,200 @@ rte_eth_dev_pool_ops_supported(uint16_t port_id, const char *pool)
>  	return (*dev->dev_ops->pool_ops_supported)(dev, pool);
>  }
> 
> +typedef int (*rte_eth_devargs_callback_t)(char *str, void *data);
> +
> +static int
> +rte_eth_devargs_tokenise(struct rte_kvargs *arglist, const char *str_in)
> +{
> +	int state;
> +	struct rte_kvargs_pair *pair;
> +	char *letter;

Hmm, so that extends rte_kvarrgs to be able to parse something like: "key=[val1,val2,...,valn]", right?
If so shouldn't it be in rte_kvargs then?
BTW, as I remember rte_kvargs allows you to have multiple identical key, i.e: "key=val1,key=val2,...,key=valn".
I suppose that approach would allow you to avoid rte_kvargs modifications.

> +
> +	arglist->str = strdup(str_in);

Who is going to free it?

> +	if (arglist->str == NULL)
> +		return -ENOMEM;
> +
> +	letter = arglist->str;
> +	state = 0;
> +	arglist->count = 0;
> +	pair = &arglist->pairs[0];
> +	while (1) {
> +		switch (state) {
> +		case 0: /* Initial */
> +			if (*letter == '=')
> +				return -EINVAL;
> +			else if (*letter == '\0')
> +				return 0;
> +
> +			state = 1;
> +			pair->key = letter;
> +			/* fall-thru */
> +
> +		case 1: /* Parsing key */
> +			if (*letter == '=') {
> +				*letter = '\0';
> +				pair->value = letter + 1;
> +				state = 2;
> +			} else if (*letter == ',' || *letter == '\0')
> +				return -EINVAL;
> +			break;
> +
> +
> +		case 2: /* Parsing value */
> +			if (*letter == '[')
> +				state = 3;
> +			else if (*letter == ',') {
> +				*letter = '\0';
> +				arglist->count++;
> +				pair = &arglist->pairs[arglist->count];
> +				state = 0;
> +			} else if (*letter == '\0') {
> +				letter--;
> +				arglist->count++;
> +				pair = &arglist->pairs[arglist->count];
> +				state = 0;
> +			}
> +			break;
> +
> +		case 3: /* Parsing list */
> +			if (*letter == ']')
> +				state = 2;
> +			else if (*letter == '\0')
> +				return -EINVAL;
> +			break;
> +		}
> +		letter++;
> +	}
> +}
> +
> +static int
> +rte_eth_devargs_parse_list(char *str, rte_eth_devargs_callback_t callback,
> +	void *data)
> +{
> +	char *str_start;
> +	int state;
> +	int result;
> +
> +	if (*str != '[')
> +		/* Single element, not a list */
> +		return callback(str, data);
> +
> +	/* Sanity check, then strip the brackets */
> +	str_start = &str[strlen(str) - 1];
> +	if (*str_start != ']') {
> +		RTE_LOG(ERR, EAL, "(%s): List does not end with ']'", str);
> +		return -EINVAL;
> +	}
> +	str++;
> +	*str_start = '\0';
> +
> +	/* Process list elements */
> +	state = 0;
> +	while (1) {
> +		if (state == 0) {
> +			if (*str == '\0')
> +				break;
> +			if (*str != ',') {
> +				str_start = str;
> +				state = 1;
> +			}
> +		} else if (state == 1) {
> +			if (*str == ',' || *str == '\0') {
> +				if (str > str_start) {
> +					/* Non-empty string fragment */
> +					*str = '\0';
> +					result = callback(str_start, data);
> +					if (result < 0)
> +						return result;
> +				}
> +				state = 0;
> +			}
> +		}
> +		str++;
> +	}
> +	return 0;
> +}
> +
> +static int
> +rte_eth_devargs_process_range(char *str, uint16_t *list, uint16_t *len_list,
> +	const uint16_t max_list)
> +{
> +	unsigned int lo;
> +	unsigned int hi;
> +	unsigned int value;
> +	int result;
> +
> +	result = sscanf(str, "%u-%u", &lo, &hi);

Should probably be %hu.
And probably check that lo and hi values are less than MAX_PORTS.

> +	if (result == 1) {
> +		if (*len_list >= max_list)
> +			return -ENOMEM;
> +		list[(*len_list)++] = lo;
> +	} else if (result == 2) {
> +		if (lo >= hi)
> +			return -EINVAL;
> +		for (value = lo; value <= hi; value++) {
> +			if (*len_list >= max_list)
> +				return -ENOMEM;
> +			list[(*len_list)++] = value;
> +		}
> +	} else
> +		return -EINVAL;
> +	return 0;
> +}
> +
> +static int
> +rte_eth_devargs_parse_ports(char *str, void *data)
> +{
> +	struct rte_eth_devargs *eth_da = data;
> +
> +	return rte_eth_devargs_process_range(str, eth_da->ports,
> +		&eth_da->nb_ports, RTE_MAX_ETHPORTS);
> +}
> +
> +
> +static int
> +rte_eth_devargs_parse_representor_ports(char *str, void *data)
> +{
> +	struct rte_eth_devargs *eth_da = data;
> +
> +	return rte_eth_devargs_process_range(str, eth_da->representor_ports,
> +		&eth_da->nb_representor_ports, RTE_MAX_ETHPORTS);
> +}
> +
> +int __rte_experimental
> +rte_eth_devargs_parse(const char *dargs, struct rte_eth_devargs *eth_da)
> +{
> +	struct rte_kvargs args;
> +	struct rte_kvargs_pair *pair;
> +	unsigned int i;
> +	int result;
> +
> +	memset(eth_da, 0, sizeof(*eth_da));
> +
> +	result = rte_eth_devargs_tokenise(&args, dargs);
> +	if (result < 0)
> +		return result;
> +
> +	for (i = 0; i < args.count; i++) {
> +		pair = &args.pairs[i];
> +
> +		if (strcmp("port", pair->key) == 0) {
> +			result = rte_eth_devargs_parse_list(pair->value,
> +				rte_eth_devargs_parse_ports, eth_da);
> +			if (result < 0)
> +				return result;
> +		} else if (strcmp("representor", pair->key) == 0) {
> +			result = rte_eth_devargs_parse_list(pair->value,
> +				rte_eth_devargs_parse_representor_ports,
> +				eth_da);
> +			if (result < 0)
> +				return result;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
>  RTE_INIT(ethdev_init_log);
>  static void
>  ethdev_init_log(void)
> diff --git a/lib/librte_ether/rte_ethdev_driver.h b/lib/librte_ether/rte_ethdev_driver.h
> index e52add0ad..3bce5747d 100644
> --- a/lib/librte_ether/rte_ethdev_driver.h
> +++ b/lib/librte_ether/rte_ethdev_driver.h
> @@ -189,6 +189,36 @@ rte_eth_linkstatus_get(const struct rte_eth_dev *dev,
>  }
> 
> 
> +/** Generic Ethernet device arguments  */
> +struct rte_eth_devargs {
> +	uint16_t ports[RTE_MAX_ETHPORTS];
> +	/** port/s number to enable on a multi-port single function */
> +	uint16_t nb_ports;
> +	/** number of ports in ports field */
> +	uint16_t representor_ports[RTE_MAX_ETHPORTS];
> +	/** representor port/s identifier to enable on device */
> +	uint16_t nb_representor_ports;
> +	/** number of ports in representor port field */
> +};
> +
> +/**
> + * @warning
> + * @b EXPERIMENTAL: this API may change without prior notice.
> + *
> + * PMD helper function to parse ethdev arguments
> + *
> + * @param devargs
> + *  device arguments
> + * @param eth_devargs
> + *  parsed ethdev specific arguments.
> + *
> + * @return
> + *   Negative errno value on error, 0 on success.
> + */
> +int __rte_experimental
> +rte_eth_devargs_parse(const char *dargs, struct rte_eth_devargs *eth_devargs);
> +
> +
>  typedef int (*ethdev_init_t)(struct rte_eth_dev *ethdev, void *init_params);
>  typedef int (*ethdev_bus_specific_init)(struct rte_eth_dev *ethdev,
>  	void *bus_specific_init_params);
> diff --git a/lib/librte_ether/rte_ethdev_version.map b/lib/librte_ether/rte_ethdev_version.map
> index bd7232923..62ecbdb8a 100644
> --- a/lib/librte_ether/rte_ethdev_version.map
> +++ b/lib/librte_ether/rte_ethdev_version.map
> @@ -233,6 +233,7 @@ EXPERIMENTAL {
>  EXPERIMENTAL {
>  	global:
> 
> +	rt_eth_devargs_parse;
>  	rte_eth_dev_create;
>  	rte_eth_dev_destroy;
> 
> --
> 2.14.3