mirror of
https://github.com/torvalds/linux.git
synced 2024-12-14 15:13:52 +00:00
f54dfdf7c6
There are currently 2 ways to create a set of sysfs files for a
kobj_type, through the default_attrs field, and the default_groups
field. Move the firmware memmap sysfs code to use default_groups field
which has been the preferred way since aa30f47cf6
("kobject: Add
support for default attribute groups to kobj_type") so that we can soon
get rid of the obsolete default_attrs field.
Link: https://lore.kernel.org/r/20220105175650.2640758-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
420 lines
12 KiB
C
420 lines
12 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* linux/drivers/firmware/memmap.c
|
|
* Copyright (C) 2008 SUSE LINUX Products GmbH
|
|
* by Bernhard Walle <bernhard.walle@gmx.de>
|
|
*/
|
|
|
|
#include <linux/string.h>
|
|
#include <linux/firmware-map.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/types.h>
|
|
#include <linux/memblock.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/mm.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 struct firmware_map_entry * __meminit
|
|
firmware_map_find_entry(u64 start, u64 end, const char *type);
|
|
|
|
/*
|
|
* 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
|
|
};
|
|
ATTRIBUTE_GROUPS(def);
|
|
|
|
static const struct sysfs_ops memmap_attr_ops = {
|
|
.show = memmap_attr_show,
|
|
};
|
|
|
|
/* Firmware memory map entries. */
|
|
static LIST_HEAD(map_entries);
|
|
static DEFINE_SPINLOCK(map_entries_lock);
|
|
|
|
/*
|
|
* For memory hotplug, there is no way to free memory map entries allocated
|
|
* by boot mem after the system is up. So when we hot-remove memory whose
|
|
* map entry is allocated by bootmem, we need to remember the storage and
|
|
* reuse it when the memory is hot-added again.
|
|
*/
|
|
static LIST_HEAD(map_entries_bootmem);
|
|
static DEFINE_SPINLOCK(map_entries_bootmem_lock);
|
|
|
|
|
|
static inline struct firmware_map_entry *
|
|
to_memmap_entry(struct kobject *kobj)
|
|
{
|
|
return container_of(kobj, struct firmware_map_entry, kobj);
|
|
}
|
|
|
|
static void __meminit release_firmware_map_entry(struct kobject *kobj)
|
|
{
|
|
struct firmware_map_entry *entry = to_memmap_entry(kobj);
|
|
|
|
if (PageReserved(virt_to_page(entry))) {
|
|
/*
|
|
* Remember the storage allocated by bootmem, and reuse it when
|
|
* the memory is hot-added again. The entry will be added to
|
|
* map_entries_bootmem here, and deleted from &map_entries in
|
|
* firmware_map_remove_entry().
|
|
*/
|
|
spin_lock(&map_entries_bootmem_lock);
|
|
list_add(&entry->list, &map_entries_bootmem);
|
|
spin_unlock(&map_entries_bootmem_lock);
|
|
|
|
return;
|
|
}
|
|
|
|
kfree(entry);
|
|
}
|
|
|
|
static struct kobj_type __refdata memmap_ktype = {
|
|
.release = release_firmware_map_entry,
|
|
.sysfs_ops = &memmap_attr_ops,
|
|
.default_groups = def_groups,
|
|
};
|
|
|
|
/*
|
|
* Registration functions ------------------------------------------------------
|
|
*/
|
|
|
|
/**
|
|
* 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 (exclusive).
|
|
* @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.
|
|
*
|
|
* Return: 0 always
|
|
*/
|
|
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 - 1;
|
|
entry->type = type;
|
|
INIT_LIST_HEAD(&entry->list);
|
|
kobject_init(&entry->kobj, &memmap_ktype);
|
|
|
|
spin_lock(&map_entries_lock);
|
|
list_add_tail(&entry->list, &map_entries);
|
|
spin_unlock(&map_entries_lock);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* firmware_map_remove_entry() - Does the real work to remove a firmware
|
|
* memmap entry.
|
|
* @entry: removed entry.
|
|
*
|
|
* The caller must hold map_entries_lock, and release it properly.
|
|
*/
|
|
static inline void firmware_map_remove_entry(struct firmware_map_entry *entry)
|
|
{
|
|
list_del(&entry->list);
|
|
}
|
|
|
|
/*
|
|
* 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 (entry->kobj.state_in_sysfs)
|
|
return -EEXIST;
|
|
|
|
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;
|
|
}
|
|
|
|
/*
|
|
* Remove memmap entry on sysfs
|
|
*/
|
|
static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
|
|
{
|
|
kobject_put(&entry->kobj);
|
|
}
|
|
|
|
/**
|
|
* firmware_map_find_entry_in_list() - Search memmap entry in a given list.
|
|
* @start: Start of the memory range.
|
|
* @end: End of the memory range (exclusive).
|
|
* @type: Type of the memory range.
|
|
* @list: In which to find the entry.
|
|
*
|
|
* This function is to find the memmap entey of a given memory range in a
|
|
* given list. The caller must hold map_entries_lock, and must not release
|
|
* the lock until the processing of the returned entry has completed.
|
|
*
|
|
* Return: Pointer to the entry to be found on success, or NULL on failure.
|
|
*/
|
|
static struct firmware_map_entry * __meminit
|
|
firmware_map_find_entry_in_list(u64 start, u64 end, const char *type,
|
|
struct list_head *list)
|
|
{
|
|
struct firmware_map_entry *entry;
|
|
|
|
list_for_each_entry(entry, list, list)
|
|
if ((entry->start == start) && (entry->end == end) &&
|
|
(!strcmp(entry->type, type))) {
|
|
return entry;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* firmware_map_find_entry() - Search memmap entry in map_entries.
|
|
* @start: Start of the memory range.
|
|
* @end: End of the memory range (exclusive).
|
|
* @type: Type of the memory range.
|
|
*
|
|
* This function is to find the memmap entey of a given memory range.
|
|
* The caller must hold map_entries_lock, and must not release the lock
|
|
* until the processing of the returned entry has completed.
|
|
*
|
|
* Return: Pointer to the entry to be found on success, or NULL on failure.
|
|
*/
|
|
static struct firmware_map_entry * __meminit
|
|
firmware_map_find_entry(u64 start, u64 end, const char *type)
|
|
{
|
|
return firmware_map_find_entry_in_list(start, end, type, &map_entries);
|
|
}
|
|
|
|
/**
|
|
* firmware_map_find_entry_bootmem() - Search memmap entry in map_entries_bootmem.
|
|
* @start: Start of the memory range.
|
|
* @end: End of the memory range (exclusive).
|
|
* @type: Type of the memory range.
|
|
*
|
|
* This function is similar to firmware_map_find_entry except that it find the
|
|
* given entry in map_entries_bootmem.
|
|
*
|
|
* Return: Pointer to the entry to be found on success, or NULL on failure.
|
|
*/
|
|
static struct firmware_map_entry * __meminit
|
|
firmware_map_find_entry_bootmem(u64 start, u64 end, const char *type)
|
|
{
|
|
return firmware_map_find_entry_in_list(start, end, type,
|
|
&map_entries_bootmem);
|
|
}
|
|
|
|
/**
|
|
* 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 (exclusive)
|
|
* @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.
|
|
*
|
|
* Return: 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 = firmware_map_find_entry(start, end - 1, type);
|
|
if (entry)
|
|
return 0;
|
|
|
|
entry = firmware_map_find_entry_bootmem(start, end - 1, type);
|
|
if (!entry) {
|
|
entry = kzalloc(sizeof(struct firmware_map_entry), GFP_ATOMIC);
|
|
if (!entry)
|
|
return -ENOMEM;
|
|
} else {
|
|
/* Reuse storage allocated by bootmem. */
|
|
spin_lock(&map_entries_bootmem_lock);
|
|
list_del(&entry->list);
|
|
spin_unlock(&map_entries_bootmem_lock);
|
|
|
|
memset(entry, 0, sizeof(*entry));
|
|
}
|
|
|
|
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.
|
|
* @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.
|
|
*
|
|
* Return: 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 = memblock_alloc(sizeof(struct firmware_map_entry),
|
|
SMP_CACHE_BYTES);
|
|
if (WARN_ON(!entry))
|
|
return -ENOMEM;
|
|
|
|
return firmware_map_add_entry(start, end, type, entry);
|
|
}
|
|
|
|
/**
|
|
* firmware_map_remove() - remove a firmware mapping entry
|
|
* @start: Start of the memory range.
|
|
* @end: End of the memory range.
|
|
* @type: Type of the memory range.
|
|
*
|
|
* removes a firmware mapping entry.
|
|
*
|
|
* Return: 0 on success, or -EINVAL if no entry.
|
|
*/
|
|
int __meminit firmware_map_remove(u64 start, u64 end, const char *type)
|
|
{
|
|
struct firmware_map_entry *entry;
|
|
|
|
spin_lock(&map_entries_lock);
|
|
entry = firmware_map_find_entry(start, end - 1, type);
|
|
if (!entry) {
|
|
spin_unlock(&map_entries_lock);
|
|
return -EINVAL;
|
|
}
|
|
|
|
firmware_map_remove_entry(entry);
|
|
spin_unlock(&map_entries_lock);
|
|
|
|
/* remove the memmap entry */
|
|
remove_sysfs_fw_map_entry(entry);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* 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);
|
|
}
|
|
|
|
static inline struct memmap_attribute *to_memmap_attr(struct attribute *attr)
|
|
{
|
|
return container_of(attr, struct memmap_attribute, attr);
|
|
}
|
|
|
|
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 firmware_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(firmware_memmap_init);
|
|
|