[Accel-config] Re: [PATCH] accel-config: Add API to return uacce device path

On 4/5/2021 5:40 PM, ramesh.thomas(a)intel.com wrote:
> From: Ramesh Thomas <ramesh.thomas(a)intel.com>
>
> Return path to uacce device path for user wqs. This includes support for
> legacy mode device names.
>
> Signed-off-by: Ramesh Thomas <ramesh.thomas(a)intel.com>
> ---
>   accfg/lib/libaccel-config.sym |  5 ++++
>   accfg/lib/libaccfg.c          | 55 +++++++++++++++++++++++++++++++++++
>   accfg/libaccel_config.h       |  1 +
>   3 files changed, 61 insertions(+)
>
> diff --git a/accfg/lib/libaccel-config.sym b/accfg/lib/libaccel-config.sym
> index 4de2a49..a28ac97 100644
> --- a/accfg/lib/libaccel-config.sym
> +++ b/accfg/lib/libaccel-config.sym
> @@ -141,3 +141,8 @@ global:
>   	accfg_remove_mdev;
>   	accfg_device_get_mdev_enabled;
>   } LIBACCFG_6;
> +
> +LIBACCFG_8 {
> +global:
> +	accfg_wq_get_uacce_path;

I wonder instead of have a specific call to uacce 
accfg_wq_get_uacce_path, we should just have 
accfg_wq_get_user_dev_path(). And it's capable of providing a path for 
legacy or uacce. And we can get users to just move over to that. The 
user really shouldn't care if it's uacce or something else.


> +} LIBACCFG_7;
> diff --git a/accfg/lib/libaccfg.c b/accfg/lib/libaccfg.c
> index 1d89d4c..dd0219c 100644
> --- a/accfg/lib/libaccfg.c
> +++ b/accfg/lib/libaccfg.c
> @@ -25,6 +25,7 @@
>   #include <ccan/build_assert/build_assert.h>
>   #include <util/sysfs.h>
>   #include <accfg/libaccel_config.h>
> +#include <fnmatch.h>
>   #include "private.h"
>   
>   #define MDEV_POSTFIX "mdev_supported_types"
> @@ -2099,6 +2100,60 @@ ACCFG_EXPORT int accfg_wq_size_boundary(struct accfg_device *device,
>   	return 0;
>   }
>   
> +ACCFG_EXPORT int accfg_wq_get_uacce_path(struct accfg_wq *wq, char *buf,
> +		size_t size)
> +{
> +	struct dirent **d;
> +	int n, n1;
> +	char *f;
> +	char p[PATH_MAX];
> +	struct accfg_ctx *ctx;
> +	int rc = 0;
> +
> +	ctx = accfg_device_get_ctx(wq->device);
> +
> +	sprintf(p, "/dev/%s", wq->device->bus_type_str);
> +	n1 = n = scandir(p, &d, NULL, alphasort);
> +	if (n < 0) {
> +		err(ctx, "UACCE device path not found %s\n", p);
> +		return -ENOENT;
> +	}
> +
> +	sprintf(p, "%s-*", accfg_wq_get_devname(wq));
> +
> +	while (n--) {
> +		f = &d[n]->d_name[0];
> +
> +		if (!fnmatch(p, f, 0) || !strcmp(accfg_wq_get_devname(wq), f))
> +			break;
> +	}
> +
> +	if (n < 0) {
> +		err(ctx, "UACCE device for %s not found at /dev/%s\n",
> +				accfg_wq_get_devname(wq),
> +				wq->device->bus_type_str);
> +		rc = -ENOENT;
> +		goto ext_uacce;
> +	}
> +
> +	n = sprintf(p, "/dev/%s/%s", wq->device->bus_type_str, f);
> +
> +	if ((size_t)n >= size) {
> +		err(ctx, "Buffer size too small. Need %d bytes\n", n + 1);
> +		rc = -ERANGE;
> +		goto ext_uacce;
> +	}
> +
> +	strcpy(buf, p);
> +
> +ext_uacce:
> +	while (n1--)
> +		free(d[n1]);
> +	free(d);
> +
> +	return rc;
> +}
> +
>   #define accfg_wq_set_field(wq, val, field) \
>   ACCFG_EXPORT int accfg_wq_set_##field( \
>   		struct accfg_wq *wq, int val) \
> diff --git a/accfg/libaccel_config.h b/accfg/libaccel_config.h
> index 94aef80..e61fd40 100644
> --- a/accfg/libaccel_config.h
> +++ b/accfg/libaccel_config.h
> @@ -276,6 +276,7 @@ int accfg_wq_enable(struct accfg_wq *wq);
>   int accfg_wq_disable(struct accfg_wq *wq, bool force);
>   int accfg_wq_priority_boundary(struct accfg_wq *wq);
>   int accfg_wq_size_boundary(struct accfg_device *device, int wq_num);
> +int accfg_wq_get_uacce_path(struct accfg_wq *wq, char *buf, size_t size);
>   
>   /* libaccfg function for engine */
>   struct accfg_engine;