Re: [PATCH v3 3/5] coresight: configfs: Modify config files to allow userspace use

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@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