[PATCH v2 3/6] coresight: configfs: Modify config files to allow userspace use

[Mike Leach <mike.leach@linaro.org>]

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         | 96 +++++++++++++------
 .../coresight/coresight-config-file.h         | 33 +++++++
 .../hwtracing/coresight/coresight-config.h    | 21 ++++
 3 files changed, 122 insertions(+), 28 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-config-file.c b/drivers/hwtracing/coresight/coresight-config-file.c
index 3fd001938324..77a64b54280d 100644
--- a/drivers/hwtracing/coresight/coresight-config-file.c
+++ b/drivers/hwtracing/coresight/coresight-config-file.c
@@ -4,10 +4,58 @@
  * Author: Mike Leach <mike.leach@linaro.org>
  */
 
-#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 +128,7 @@ 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 +138,13 @@ 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;
 
-	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 +155,12 @@ 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 +187,7 @@ 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 +213,7 @@ 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 +228,8 @@ 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 +307,7 @@ 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 +346,8 @@ 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 +361,8 @@ 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 +439,7 @@ int cscfg_file_read_buffer(const u8 *buffer, const int buflen,
 		if (err)
 			return err;
 	}
-	return used;
+	return 0;
 }
 
 int cscfg_file_read_buffer_first_name(const u8 *buffer, const int buflen,
diff --git a/drivers/hwtracing/coresight/coresight-config-file.h b/drivers/hwtracing/coresight/coresight-config-file.h
index 03899f7d94c9..04c365e5109b 100644
--- a/drivers/hwtracing/coresight/coresight-config-file.h
+++ b/drivers/hwtracing/coresight/coresight-config-file.h
@@ -7,6 +7,39 @@
 #ifndef _CORESIGHT_CORESIGHT_CONFIG_FILE_H
 #define _CORESIGHT_CORESIGHT_CONFIG_FILE_H
 
+#include <linux/types.h>
+
+#ifndef __KERNEL__
+/*
+ * allow the user space programs to include the coresight config headers
+ * to use the _desc structures, and reuse the read code
+ */
+#ifndef u8
+typedef __u8 u8;
+typedef __u16 u16;
+typedef __u32 u32;
+typedef __u64 u64;
+#endif
+
+/* ARRAY SIZE is useful too */
+#ifndef ARRAY_SIZE
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
+#endif
+
+/* define EINVAL for user space */
+#ifndef EINVAL
+#define EINVAL 22
+#endif
+
+#ifndef ENOMEM
+#define ENOMEM 12
+#endif
+
+#endif
+
+#include "coresight-config.h"
+
+
 /*
  * Structures to represent configuration descriptors in a memory buffer
  * to serialise to and from files
diff --git a/drivers/hwtracing/coresight/coresight-config.h b/drivers/hwtracing/coresight/coresight-config.h
index 770986316bc2..2136393df710 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 */
@@ -103,14 +110,18 @@ struct cscfg_regval_desc {
 struct cscfg_feature_desc {
 	const char *name;
 	const char *description;
+#ifdef __KERNEL__
 	struct list_head item;
+#endif
 	u32 match_flags;
 	int nr_params;
 	struct cscfg_parameter_desc *params_desc;
 	int nr_regs;
 	struct cscfg_regval_desc *regs_desc;
+#ifdef __KERNEL__
 	void *load_owner;
 	struct config_group *fs_group;
+#endif
 };
 
 /**
@@ -138,16 +149,20 @@ struct cscfg_feature_desc {
 struct cscfg_config_desc {
 	const char *name;
 	const char *description;
+#ifdef __KERNEL__
 	struct list_head item;
+#endif
 	int nr_feat_refs;
 	const char **feat_ref_names;
 	int nr_presets;
 	int nr_total_params;
 	const u64 *presets; /* nr_presets * nr_total_params */
+#ifdef __KERNEL__
 	struct dev_ext_attribute *event_ea;
 	atomic_t active_cnt;
 	void *load_owner;
 	struct config_group *fs_group;
+#endif
 };
 
 /**
@@ -162,11 +177,16 @@ struct cscfg_config_desc {
  * @feat_descs:		array of feature descriptor pointers.
  */
 struct cscfg_fs_load_descs {
+#ifdef __KERNEL__
 	void *owner_info;
+#endif
 	struct cscfg_config_desc **config_descs;
 	struct cscfg_feature_desc **feat_descs;
 };
 
+/* remainder of header is used by the kernel drivers only */
+#ifdef __KERNEL__
+
 /**
  * config register instance - part of a loaded feature.
  *                            maps register values to csdev driver structures
@@ -274,4 +294,5 @@ 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


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