[PATCH v3 3/5] coresight: configfs: Modify config files to allow userspace use
Mathieu Poirier
mathieu.poirier at linaro.org
Wed May 25 12:57:42 PDT 2022
On Thu, Apr 14, 2022 at 07:44:55AM +0100, Mike Leach wrote:
> Update coresight-config.h and the coresight-config-file.c & .h
> to allow use in userspace programs.
>
> Use __KERNEL__ defines to filter out driver only structures and
> elements so that user space programs can use the descriptor structures.
>
> Abstract memory allocation in coresight-config-file.c to allow read
> file functions to be run in userspace and kernel drivers.
>
> Signed-off-by: Mike Leach <mike.leach at linaro.org>
> ---
> .../coresight/coresight-config-file.c | 95 +++++++++++++------
> .../hwtracing/coresight/coresight-config.h | 12 +++
> 2 files changed, 80 insertions(+), 27 deletions(-)
>
> diff --git a/drivers/hwtracing/coresight/coresight-config-file.c b/drivers/hwtracing/coresight/coresight-config-file.c
> index 3fd001938324..5b8f635ac50e 100644
> --- a/drivers/hwtracing/coresight/coresight-config-file.c
> +++ b/drivers/hwtracing/coresight/coresight-config-file.c
> @@ -6,8 +6,57 @@
>
> #include "coresight-config.h"
> #include "coresight-config-file.h"
> +
> +/*
> + * To allow reuse of this source in tools, define memory allocation fns according
> + * to build environment.
> + */
> +
> +#ifdef __KERNEL__
> #include "coresight-syscfg.h"
>
> +static void *cscfg_calloc(size_t num, size_t size)
> +{
> + return devm_kcalloc(cscfg_device(), num, size, GFP_KERNEL);
> +}
> +
> +static char *cscfg_strdup(const char *str)
> +{
> + return devm_kstrdup(cscfg_device(), str, GFP_KERNEL);
> +}
> +
> +static void *cscfg_zalloc(size_t size)
> +{
> + return devm_kzalloc(cscfg_device(), size, GFP_KERNEL);
> +}
> +
> +#else
> +
> +#include <stddef.h>
> +#include <string.h>
> +#include <stdlib.h>
> +
> +static void *cscfg_calloc(size_t num, size_t size)
> +{
> + return calloc(num, size);
> +}
> +
> +static char *cscfg_strdup(const char *str)
> +{
> + return strdup(str);
> +}
> +
> +static void *cscfg_zalloc(size_t size)
> +{
> + void *ptr = malloc(size);
> +
> + if (ptr)
> + memset(ptr, 0, size);
> + return ptr;
> +}
> +
> +#endif
> +
> #define cscfg_extract_u64(val64) { \
> val64 = *(u64 *)(buffer + used); \
> used += sizeof(u64); \
> @@ -80,6 +129,7 @@ static int cscfg_file_read_elem_str(const u8 *buffer, const int buflen, int *buf
> struct cscfg_file_elem_str *elem_str)
> {
> int used = *buf_used;
> + const u8 *str;
>
> if ((buflen - used) < sizeof(u16))
> return -EINVAL;
> @@ -89,11 +139,13 @@ static int cscfg_file_read_elem_str(const u8 *buffer, const int buflen, int *buf
> if ((buflen - used) < elem_str->str_len)
> return -EINVAL;
>
> + str = buffer + used;
> +
> /* check for 0 termination */
> - if (buffer[elem_str->str_len - 1] != 0)
> + if (str[elem_str->str_len - 1] != 0)
> return -EINVAL;
>
Now it makes sense.
> - elem_str->str = devm_kstrdup(cscfg_device(), (char *)buffer, GFP_KERNEL);
> + elem_str->str = cscfg_strdup((char *)str);
> used += elem_str->str_len;
>
> *buf_used = used;
> @@ -104,14 +156,12 @@ static int cscfg_file_alloc_desc_arrays(struct cscfg_fs_load_descs *desc_arrays,
> int nr_features)
> {
> /* arrays are 0 terminated - max of 1 config & nr_features features */
> - desc_arrays->config_descs = devm_kcalloc(cscfg_device(), 2,
> - sizeof(struct cscfg_config_desc *),
> - GFP_KERNEL);
> + desc_arrays->config_descs = cscfg_calloc(2, sizeof(struct cscfg_config_desc *));
> if (!desc_arrays->config_descs)
> return -ENOMEM;
> - desc_arrays->feat_descs = devm_kcalloc(cscfg_device(), nr_features + 1,
> - sizeof(struct cscfg_feature_desc *),
> - GFP_KERNEL);
> +
> + desc_arrays->feat_descs = cscfg_calloc(nr_features + 1,
> + sizeof(struct cscfg_feature_desc *));
> if (!desc_arrays->feat_descs)
> return -ENOMEM;
> return 0;
> @@ -138,8 +188,7 @@ static int cscfg_file_read_elem_config(const u8 *buffer, const int buflen, int *
> return 0;
>
> /* we have a config - allocate the descriptor */
> - config_desc = devm_kzalloc(cscfg_device(), sizeof(struct cscfg_config_desc),
> - GFP_KERNEL);
> + config_desc = cscfg_zalloc(sizeof(struct cscfg_config_desc));
> if (!config_desc)
> return -ENOMEM;
>
> @@ -165,8 +214,7 @@ static int cscfg_file_read_elem_config(const u8 *buffer, const int buflen, int *
> /* read the array of 64bit presets if present */
> nr_preset_vals = config_desc->nr_total_params * config_desc->nr_presets;
> if (nr_preset_vals) {
> - presets = devm_kcalloc(cscfg_device(), nr_preset_vals,
> - sizeof(u64), GFP_KERNEL);
> + presets = cscfg_calloc(nr_preset_vals, sizeof(u64));
> if (!presets)
> return -ENOMEM;
>
> @@ -181,10 +229,8 @@ static int cscfg_file_read_elem_config(const u8 *buffer, const int buflen, int *
>
> /* read the array of feature names referenced by the config */
> if (config_desc->nr_feat_refs) {
> - config_desc->feat_ref_names = devm_kcalloc(cscfg_device(),
> - config_desc->nr_feat_refs,
> - sizeof(char *),
> - GFP_KERNEL);
> + config_desc->feat_ref_names = cscfg_calloc(config_desc->nr_feat_refs,
> + sizeof(char *));
> if (!config_desc->feat_ref_names)
> return -ENOMEM;
>
> @@ -262,8 +308,7 @@ static int cscfg_file_read_elem_feature(const u8 *buffer, const int buflen, int
> u32 val32;
>
> /* allocate the feature descriptor object */
> - feat_desc = devm_kzalloc(cscfg_device(), sizeof(struct cscfg_feature_desc),
> - GFP_KERNEL);
> + feat_desc = cscfg_zalloc(sizeof(struct cscfg_feature_desc));
> if (!feat_desc)
> return -ENOMEM;
>
> @@ -302,10 +347,8 @@ static int cscfg_file_read_elem_feature(const u8 *buffer, const int buflen, int
> nr_regs_bytes = ((sizeof(u32) + sizeof(u64)) * feat_desc->nr_regs);
> if ((buflen - used) < nr_regs_bytes)
> return -EINVAL;
> - feat_desc->regs_desc = devm_kcalloc(cscfg_device(),
> - feat_desc->nr_regs,
> - sizeof(struct cscfg_regval_desc),
> - GFP_KERNEL);
> + feat_desc->regs_desc = cscfg_calloc(feat_desc->nr_regs,
> + sizeof(struct cscfg_regval_desc));
> if (!feat_desc->regs_desc)
> return -ENOMEM;
>
> @@ -319,10 +362,8 @@ static int cscfg_file_read_elem_feature(const u8 *buffer, const int buflen, int
>
> /* parameter descriptors - string + 64 bit value */
> if (feat_desc->nr_params) {
> - feat_desc->params_desc = devm_kcalloc(cscfg_device(),
> - feat_desc->nr_params,
> - sizeof(struct cscfg_parameter_desc),
> - GFP_KERNEL);
> + feat_desc->params_desc = cscfg_calloc(feat_desc->nr_params,
> + sizeof(struct cscfg_parameter_desc));
> if (!feat_desc->params_desc)
> return -ENOMEM;
> for (i = 0; i < feat_desc->nr_params; i++) {
> @@ -399,7 +440,7 @@ int cscfg_file_read_buffer(const u8 *buffer, const int buflen,
> if (err)
> return err;
> }
> - return used;
> + return 0;
This belongs in patch 1.
> }
>
> int cscfg_file_read_buffer_first_name(const u8 *buffer, const int buflen,
> diff --git a/drivers/hwtracing/coresight/coresight-config.h b/drivers/hwtracing/coresight/coresight-config.h
> index 9cd3c26ce023..fce74e2fbd0c 100644
> --- a/drivers/hwtracing/coresight/coresight-config.h
> +++ b/drivers/hwtracing/coresight/coresight-config.h
> @@ -7,7 +7,14 @@
> #ifndef _CORESIGHT_CORESIGHT_CONFIG_H
> #define _CORESIGHT_CORESIGHT_CONFIG_H
>
> +/*
> + * Filter out kernel only portions of the file to allow user space programs
> + * to use the descriptor definitions.
> + */
> +#ifdef __KERNEL__
> #include <linux/coresight.h>
> +#endif
> +
> #include <linux/types.h>
>
> /* CoreSight Configuration Management - component and system wide configuration */
> @@ -100,6 +107,10 @@ struct cscfg_fs_load_descs {
> struct cscfg_feature_desc **feat_descs;
> };
>
> +
> +/* remainder of header is used by the kernel drivers only */
> +#ifdef __KERNEL__
> +
> /**
> * Device feature descriptor - combination of registers and parameters to
> * program a device to implement a specific complex function.
> @@ -272,4 +283,5 @@ void cscfg_csdev_disable_config(struct cscfg_config_csdev *config_csdev);
> /* reset a feature to default values */
> void cscfg_reset_feat(struct cscfg_feature_csdev *feat_csdev);
>
> +#endif /* __KERNEL__ */
> #endif /* _CORESIGHT_CORESIGHT_CONFIG_H */
> --
> 2.17.1
>
More information about the linux-arm-kernel
mailing list