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/* * linux/drivers/firmware/memmap.c *  Copyright (C) 2008 SUSE LINUX Products GmbH *  by Bernhard Walle <bernhard.walle@gmx.de> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License v2.0 as published by * the Free Software Foundation * * 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.  See the * GNU General Public License for more details. * */ #include <linux/string.h>#include <linux/firmware-map.h>#include <linux/kernel.h>#include <linux/module.h>#include <linux/types.h>#include <linux/bootmem.h>#include <linux/slab.h> /* * Data types ------------------------------------------------------------------ */ /* * Firmware map entry. Because firmware memory maps are flat and not * hierarchical, it's ok to organise them in a linked list. No parent * information is necessary as for the resource tree. */struct firmware_map_entry {	/*	 * start and end must be u64 rather than resource_size_t, because e820	 * resources can lie at addresses above 4G.	 */	u64			start;	/* start of the memory range */	u64			end;	/* end of the memory range (incl.) */	const char		*type;	/* type of the memory range */	struct list_head	list;	/* entry for the linked list */	struct kobject		kobj;   /* kobject for each entry */}; /* * Forward declarations -------------------------------------------------------- */static ssize_t memmap_attr_show(struct kobject *kobj,				struct attribute *attr, char *buf);static ssize_t start_show(struct firmware_map_entry *entry, char *buf);static ssize_t end_show(struct firmware_map_entry *entry, char *buf);static ssize_t type_show(struct firmware_map_entry *entry, char *buf); /* * Static data ----------------------------------------------------------------- */ struct memmap_attribute {	struct attribute attr;	ssize_t (*show)(struct firmware_map_entry *entry, char *buf);}; static struct memmap_attribute memmap_start_attr = __ATTR_RO(start);static struct memmap_attribute memmap_end_attr   = __ATTR_RO(end);static struct memmap_attribute memmap_type_attr  = __ATTR_RO(type); /* * These are default attributes that are added for every memmap entry. */static struct attribute *def_attrs[] = {	&memmap_start_attr.attr,	&memmap_end_attr.attr,	&memmap_type_attr.attr,	NULL}; static const struct sysfs_ops memmap_attr_ops = {	.show = memmap_attr_show,}; static struct kobj_type memmap_ktype = {	.sysfs_ops	= &memmap_attr_ops,	.default_attrs	= def_attrs,}; /* * Registration functions ------------------------------------------------------ */ /* * Firmware memory map entries. No locking is needed because the * firmware_map_add() and firmware_map_add_early() functions are called * in firmware initialisation code in one single thread of execution. */static LIST_HEAD(map_entries); /** * firmware_map_add_entry() - Does the real work to add a firmware memmap entry. * @start: Start of the memory range. * @end:   End of the memory range (inclusive). * @type:  Type of the memory range. * @entry: Pre-allocated (either kmalloc() or bootmem allocator), uninitialised *         entry. * * Common implementation of firmware_map_add() and firmware_map_add_early() * which expects a pre-allocated struct firmware_map_entry. **/static int firmware_map_add_entry(u64 start, u64 end,				  const char *type,				  struct firmware_map_entry *entry){	BUG_ON(start > end); 	entry->start = start;	entry->end = end;	entry->type = type;	INIT_LIST_HEAD(&entry->list);	kobject_init(&entry->kobj, &memmap_ktype); 	list_add_tail(&entry->list, &map_entries); 	return 0;} /* * Add memmap entry on sysfs */static int add_sysfs_fw_map_entry(struct firmware_map_entry *entry){	static int map_entries_nr;	static struct kset *mmap_kset; 	if (!mmap_kset) {		mmap_kset = kset_create_and_add("memmap", NULL, firmware_kobj);		if (!mmap_kset)			return -ENOMEM;	} 	entry->kobj.kset = mmap_kset;	if (kobject_add(&entry->kobj, NULL, "%d", map_entries_nr++))		kobject_put(&entry->kobj); 	return 0;} /** * firmware_map_add_hotplug() - Adds a firmware mapping entry when we do * memory hotplug. * @start: Start of the memory range. * @end:   End of the memory range (inclusive). * @type:  Type of the memory range. * * Adds a firmware mapping entry. This function is for memory hotplug, it is * similar to function firmware_map_add_early(). The only difference is that * it will create the syfs entry dynamically. * * Returns 0 on success, or -ENOMEM if no memory could be allocated. **/int __meminit firmware_map_add_hotplug(u64 start, u64 end, const char *type){	struct firmware_map_entry *entry; 	entry = kzalloc(sizeof(struct firmware_map_entry), GFP_ATOMIC);	if (!entry)		return -ENOMEM; 	firmware_map_add_entry(start, end, type, entry);	/* create the memmap entry */	add_sysfs_fw_map_entry(entry); 	return 0;} /** * firmware_map_add_early() - Adds a firmware mapping entry. * @start: Start of the memory range. * @end:   End of the memory range (inclusive). * @type:  Type of the memory range. * * Adds a firmware mapping entry. This function uses the bootmem allocator * for memory allocation. * * That function must be called before late_initcall. * * Returns 0 on success, or -ENOMEM if no memory could be allocated. **/int __init firmware_map_add_early(u64 start, u64 end, const char *type){	struct firmware_map_entry *entry; 	entry = alloc_bootmem(sizeof(struct firmware_map_entry));	if (WARN_ON(!entry))		return -ENOMEM; 	return firmware_map_add_entry(start, end, type, entry);} /* * Sysfs functions ------------------------------------------------------------- */ static ssize_t start_show(struct firmware_map_entry *entry, char *buf){	return snprintf(buf, PAGE_SIZE, "0x%llx\n",		(unsigned long long)entry->start);} static ssize_t end_show(struct firmware_map_entry *entry, char *buf){	return snprintf(buf, PAGE_SIZE, "0x%llx\n",		(unsigned long long)entry->end);} static ssize_t type_show(struct firmware_map_entry *entry, char *buf){	return snprintf(buf, PAGE_SIZE, "%s\n", entry->type);} #define to_memmap_attr(_attr) container_of(_attr, struct memmap_attribute, attr)#define to_memmap_entry(obj) container_of(obj, struct firmware_map_entry, kobj) static ssize_t memmap_attr_show(struct kobject *kobj,				struct attribute *attr, char *buf){	struct firmware_map_entry *entry = to_memmap_entry(kobj);	struct memmap_attribute *memmap_attr = to_memmap_attr(attr); 	return memmap_attr->show(entry, buf);} /* * Initialises stuff and adds the entries in the map_entries list to * sysfs. Important is that firmware_map_add() and firmware_map_add_early() * must be called before late_initcall. That's just because that function * is called as late_initcall() function, which means that if you call * firmware_map_add() or firmware_map_add_early() afterwards, the entries * are not added to sysfs. */static int __init memmap_init(void){	struct firmware_map_entry *entry; 	list_for_each_entry(entry, &map_entries, list)		add_sysfs_fw_map_entry(entry); 	return 0;}late_initcall(memmap_init);