1 files changed, 348 insertions, 0 deletions
diff --git a/drivers/staging/unisys/visorutil/procobjecttree.c b/drivers/staging/unisys/visorutil/procobjecttree.c
new file mode 100644
index 000000000000..67a19e1c7b02
--- /dev/null
+++ b/drivers/staging/unisys/visorutil/procobjecttree.c
@@ -0,0 +1,348 @@
+/* procobjecttree.c
+ *
+ * Copyright © 2010 - 2013 UNISYS CORPORATION
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT.  See the GNU General Public License for more
+ * details.
+ */
+
+#include "procobjecttree.h"
+
+#define MYDRVNAME "procobjecttree"
+
+
+
+/** This is context info that we stash in each /proc file entry, which we
+ *  need in order to call the callback function that supplies the /proc read
+ *  info for that file.
+ */
+typedef struct {
+	void (*show_property)(struct seq_file *, void *, int);
+	MYPROCOBJECT *procObject;
+	int propertyIndex;
+
+} PROCDIRENTRYCONTEXT;
+
+/** This describes the attributes of a tree rooted at
+ *  <procDirRoot>/<name[0]>/<name[1]>/...
+ *  Properties for each object of this type will be located under
+ *  <procDirRoot>/<name[0]>/<name[1]>/.../<objectName>/<propertyName>.
+ */
+struct MYPROCTYPE_Tag {
+	const char **name;  /**< node names for this type, ending with NULL */
+	int nNames;         /**< num of node names in <name> */
+
+	/** root dir for this type tree in /proc */
+	struct proc_dir_entry *procDirRoot;
+
+	struct proc_dir_entry **procDirs;  /**< for each node in <name> */
+
+	/** bottom dir where objects will be rooted; i.e., this is
+	 *  <procDirRoot>/<name[0]>/<name[1]>/.../, which is the same as the
+	 *  last entry in the <procDirs> array. */
+	struct proc_dir_entry *procDir;
+
+	/** name for each property that objects of this type can have */
+	const char **propertyNames;
+
+	int nProperties;       /**< num of names in <propertyNames> */
+
+	/** Call this, passing MYPROCOBJECT.context and the property index
+	 *  whenever someone reads the proc entry */
+	void (*show_property)(struct seq_file *, void *, int);
+};
+
+
+
+struct MYPROCOBJECT_Tag {
+	MYPROCTYPE *type;
+
+	/** This is the name of the dir node in /proc under which the
+	 *  properties of this object will appear as files. */
+	char *name;
+
+	int namesize;   /**< number of bytes allocated for name */
+	void *context;  /**< passed to MYPROCTYPE.show_property */
+
+	/** <type.procDirRoot>/<type.name[0]>/<type.name[1]>/.../<name> */
+	struct proc_dir_entry *procDir;
+
+	/** a proc dir entry for each of the properties of the object;
+	 *  properties are identified in MYPROCTYPE.propertyNames, so each of
+	 *  the <procDirProperties> describes a single file like
+	 *  <type.procDirRoot>/<type.name[0]>/<type.name[1]>/...
+	 *           /<name>/<propertyName>
+	 */
+	struct proc_dir_entry **procDirProperties;
+
+	/** this is a holding area for the context information that is needed
+	 *  to run the /proc callback function */
+	PROCDIRENTRYCONTEXT *procDirPropertyContexts;
+};
+
+
+
+static struct proc_dir_entry *
+createProcDir(const char *name, struct proc_dir_entry *parent)
+{
+	struct proc_dir_entry *p = proc_mkdir_mode(name, S_IFDIR, parent);
+	if (p == NULL)
+		ERRDRV("failed to create /proc directory %s", name);
+	return p;
+}
+
+static struct proc_dir_entry *
+createProcFile(const char *name, struct proc_dir_entry *parent,
+	       const struct file_operations *fops, void *data)
+{
+	struct proc_dir_entry *p = proc_create_data(name, 0, parent,
+						    fops, data);
+	if (p == NULL)
+		ERRDRV("failed to create /proc file %s", name);
+	return p;
+}
+
+static int seq_show(struct seq_file *seq, void *offset);
+static int proc_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, seq_show, PDE_DATA(inode));
+}
+
+static const struct file_operations proc_fops = {
+	.open = proc_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = single_release,
+};
+
+
+
+MYPROCTYPE *visor_proc_CreateType(struct proc_dir_entry *procDirRoot,
+				  const char **name,
+				  const char **propertyNames,
+				  void (*show_property)(struct seq_file *,
+							void *, int))
+{
+	int i = 0;
+	MYPROCTYPE *rc = NULL, *type = NULL;
+	struct proc_dir_entry *parent = NULL;
+
+	if (procDirRoot == NULL) {
+		ERRDRV("procDirRoot cannot be NULL!\n");
+		goto Away;
+	}
+	if (name == NULL || name[0] == NULL) {
+		ERRDRV("name must contain at least 1 node name!\n");
+		goto Away;
+	}
+	type = kzalloc(sizeof(MYPROCTYPE), GFP_KERNEL | __GFP_NORETRY);
+	if (type == NULL) {
+		ERRDRV("out of memory\n");
+		goto Away;
+	}
+	type->name = name;
+	type->propertyNames = propertyNames;
+	type->nProperties = 0;
+	type->nNames = 0;
+	type->show_property = show_property;
+	type->procDirRoot = procDirRoot;
+	if (type->propertyNames != NULL)
+		while (type->propertyNames[type->nProperties] != NULL)
+			type->nProperties++;
+	while (type->name[type->nNames] != NULL)
+		type->nNames++;
+	type->procDirs = kzalloc((type->nNames + 1) *
+				 sizeof(struct proc_dir_entry *),
+				 GFP_KERNEL | __GFP_NORETRY);
+	if (type->procDirs == NULL) {
+		ERRDRV("out of memory\n");
+		goto Away;
+	}
+	parent = procDirRoot;
+	for (i = 0; i < type->nNames; i++) {
+		type->procDirs[i] = createProcDir(type->name[i], parent);
+		if (type->procDirs[i] == NULL) {
+			rc = NULL;
+			goto Away;
+		}
+		parent = type->procDirs[i];
+	}
+	type->procDir = type->procDirs[type->nNames-1];
+	rc = type;
+Away:
+	if (rc == NULL) {
+		if (type != NULL) {
+			visor_proc_DestroyType(type);
+			type = NULL;
+		}
+	}
+	return rc;
+}
+EXPORT_SYMBOL_GPL(visor_proc_CreateType);
+
+
+
+void visor_proc_DestroyType(MYPROCTYPE *type)
+{
+	if (type == NULL)
+		return;
+	if (type->procDirs != NULL) {
+		int i = type->nNames-1;
+		while (i >= 0) {
+			if (type->procDirs[i] != NULL) {
+				struct proc_dir_entry *parent = NULL;
+				if (i == 0)
+					parent = type->procDirRoot;
+				else
+					parent = type->procDirs[i-1];
+				remove_proc_entry(type->name[i], parent);
+			}
+			i--;
+		}
+		kfree(type->procDirs);
+		type->procDirs = NULL;
+	}
+	kfree(type);
+}
+EXPORT_SYMBOL_GPL(visor_proc_DestroyType);
+
+
+
+MYPROCOBJECT *visor_proc_CreateObject(MYPROCTYPE *type,
+				      const char *name, void *context)
+{
+	MYPROCOBJECT *obj = NULL, *rc = NULL;
+	int i = 0;
+
+	if (type == NULL) {
+		ERRDRV("type cannot be NULL\n");
+		goto Away;
+	}
+	obj = kzalloc(sizeof(MYPROCOBJECT), GFP_KERNEL | __GFP_NORETRY);
+	if (obj == NULL) {
+		ERRDRV("out of memory\n");
+		goto Away;
+	}
+	obj->type = type;
+	obj->context = context;
+	if (name == NULL) {
+		obj->name = NULL;
+		obj->procDir = type->procDir;
+	} else {
+		obj->namesize = strlen(name)+1;
+		obj->name = kmalloc(obj->namesize, GFP_KERNEL | __GFP_NORETRY);
+		if (obj->name == NULL) {
+			obj->namesize = 0;
+			ERRDRV("out of memory\n");
+			goto Away;
+		}
+		strcpy(obj->name, name);
+		obj->procDir = createProcDir(obj->name, type->procDir);
+		if (obj->procDir == NULL) {
+			goto Away;
+		}
+	}
+	obj->procDirPropertyContexts =
+		kzalloc((type->nProperties + 1) * sizeof(PROCDIRENTRYCONTEXT),
+			GFP_KERNEL | __GFP_NORETRY);
+	if (obj->procDirPropertyContexts == NULL) {
+		ERRDRV("out of memory\n");
+		goto Away;
+	}
+	obj->procDirProperties =
+		kzalloc((type->nProperties + 1) * sizeof(struct proc_dir_entry *),
+			GFP_KERNEL | __GFP_NORETRY);
+	if (obj->procDirProperties == NULL) {
+		ERRDRV("out of memory\n");
+		goto Away;
+	}
+	for (i = 0; i < type->nProperties; i++) {
+		obj->procDirPropertyContexts[i].procObject = obj;
+		obj->procDirPropertyContexts[i].propertyIndex = i;
+		obj->procDirPropertyContexts[i].show_property =
+			type->show_property;
+		if (type->propertyNames[i][0] != '\0') {
+			/* only create properties that have names */
+			obj->procDirProperties[i] =
+				createProcFile(type->propertyNames[i],
+					       obj->procDir, &proc_fops,
+					       &obj->procDirPropertyContexts[i]);
+			if (obj->procDirProperties[i] == NULL) {
+				rc = NULL;
+				goto Away;
+			}
+		}
+	}
+	rc = obj;
+Away:
+	if (rc == NULL) {
+		if (obj != NULL) {
+			visor_proc_DestroyObject(obj);
+			obj = NULL;
+		}
+	}
+	return rc;
+}
+EXPORT_SYMBOL_GPL(visor_proc_CreateObject);
+
+
+
+void visor_proc_DestroyObject(MYPROCOBJECT *obj)
+{
+	MYPROCTYPE *type = NULL;
+	if (obj == NULL)
+		return;
+	type = obj->type;
+	if (type == NULL)
+		return;
+	if (obj->procDirProperties != NULL) {
+		int i = 0;
+		for (i = 0; i < type->nProperties; i++) {
+			if (obj->procDirProperties[i] != NULL) {
+				remove_proc_entry(type->propertyNames[i],
+						  obj->procDir);
+				obj->procDirProperties[i] = NULL;
+			}
+		}
+		kfree(obj->procDirProperties);
+		obj->procDirProperties = NULL;
+	}
+	if (obj->procDirPropertyContexts != NULL) {
+		kfree(obj->procDirPropertyContexts);
+		obj->procDirPropertyContexts = NULL;
+	}
+	if (obj->procDir != NULL) {
+		if (obj->name != NULL)
+			remove_proc_entry(obj->name, type->procDir);
+		obj->procDir = NULL;
+	}
+	if (obj->name != NULL) {
+		kfree(obj->name);
+		obj->name = NULL;
+	}
+	kfree(obj);
+}
+EXPORT_SYMBOL_GPL(visor_proc_DestroyObject);
+
+
+
+static int seq_show(struct seq_file *seq, void *offset)
+{
+	PROCDIRENTRYCONTEXT *ctx = (PROCDIRENTRYCONTEXT *)(seq->private);
+	if (ctx == NULL) {
+		ERRDRV("I don't have a freakin' clue...");
+		return 0;
+	}
+	(*ctx->show_property)(seq, ctx->procObject->context,
+			      ctx->propertyIndex);
+	return 0;
+}