- 根目录:
- drivers
- base
- firmware_class.c
/*
* firmware_class.c - Multi purpose firmware loading support
*
* Copyright (c) 2003 Manuel Estrada Sainz
*
* Please see Documentation/firmware_class/ for more information.
*
*/
#include <linux/capability.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/timer.h>
#include <linux/vmalloc.h>
#include <linux/interrupt.h>
#include <linux/bitops.h>
#include <linux/mutex.h>
#include <linux/workqueue.h>
#include <linux/highmem.h>
#include <linux/firmware.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/file.h>
#include <linux/list.h>
#include <linux/async.h>
#include <linux/pm.h>
#include <linux/suspend.h>
#include <linux/syscore_ops.h>
#include <linux/reboot.h>
#include <generated/utsrelease.h>
#include "base.h"
MODULE_AUTHOR("Manuel Estrada Sainz");
MODULE_DESCRIPTION("Multi purpose firmware loading support");
MODULE_LICENSE("GPL");
/* Builtin firmware support */
#ifdef CONFIG_FW_LOADER
extern struct builtin_fw __start_builtin_fw[];
extern struct builtin_fw __end_builtin_fw[];
static bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
{
struct builtin_fw *b_fw;
for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
if (strcmp(name, b_fw->name) == 0) {
fw->size = b_fw->size;
fw->data = b_fw->data;
return true;
}
}
return false;
}
static bool fw_is_builtin_firmware(const struct firmware *fw)
{
struct builtin_fw *b_fw;
for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
if (fw->data == b_fw->data)
return true;
return false;
}
#else /* Module case - no builtin firmware support */
static inline bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
{
return false;
}
static inline bool fw_is_builtin_firmware(const struct firmware *fw)
{
return false;
}
#endif
enum {
FW_STATUS_LOADING,
FW_STATUS_DONE,
FW_STATUS_ABORT,
};
static int loading_timeout = 60; /* In seconds */
static inline long firmware_loading_timeout(void)
{
return loading_timeout > 0 ? loading_timeout * HZ : MAX_SCHEDULE_TIMEOUT;
}
struct firmware_cache {
/* firmware_buf instance will be added into the below list */
spinlock_t lock;
struct list_head head;
int state;
#ifdef CONFIG_PM_SLEEP
/*
* Names of firmware images which have been cached successfully
* will be added into the below list so that device uncache
* helper can trace which firmware images have been cached
* before.
*/
spinlock_t name_lock;
struct list_head fw_names;
struct delayed_work work;
struct notifier_block pm_notify;
#endif
};
struct firmware_buf {
struct kref ref;
struct list_head list;
struct completion completion;
struct firmware_cache *fwc;
unsigned long status;
void *data;
size_t size;
#ifdef CONFIG_FW_LOADER_USER_HELPER
bool is_paged_buf;
struct page **pages;
int nr_pages;
int page_array_size;
struct list_head pending_list;
#endif
char fw_id[];
};
struct fw_cache_entry {
struct list_head list;
char name[];
};
struct fw_name_devm {
unsigned long magic;
char name[];
};
#define to_fwbuf(d) container_of(d, struct firmware_buf, ref)
#define FW_LOADER_NO_CACHE 0
#define FW_LOADER_START_CACHE 1
static int fw_cache_piggyback_on_request(const char *name);
/* fw_lock could be moved to 'struct firmware_priv' but since it is just
* guarding for corner cases a global lock should be OK */
static DEFINE_MUTEX(fw_lock);
static struct firmware_cache fw_cache;
static struct firmware_buf *__allocate_fw_buf(const char *fw_name,
struct firmware_cache *fwc)
{
struct firmware_buf *buf;
buf = kzalloc(sizeof(*buf) + strlen(fw_name) + 1 , GFP_ATOMIC);
if (!buf)
return buf;
kref_init(&buf->ref);
strcpy(buf->fw_id, fw_name);
buf->fwc = fwc;
init_completion(&buf->completion);
#ifdef CONFIG_FW_LOADER_USER_HELPER
INIT_LIST_HEAD(&buf->pending_list);
#endif
pr_debug("%s: fw-%s buf=%p\n", __func__, fw_name, buf);
return buf;
}
static struct firmware_buf *__fw_lookup_buf(const char *fw_name)
{
struct firmware_buf *tmp;
struct firmware_cache *fwc = &fw_cache;
list_for_each_entry(tmp, &fwc->head, list)
if (!strcmp(tmp->fw_id, fw_name))
return tmp;
return NULL;
}
static int fw_lookup_and_allocate_buf(const char *fw_name,
struct firmware_cache *fwc,
struct firmware_buf **buf)
{
struct firmware_buf *tmp;
spin_lock(&fwc->lock);
tmp = __fw_lookup_buf(fw_name);
if (tmp) {
kref_get(&tmp->ref);
spin_unlock(&fwc->lock);
*buf = tmp;
return 1;
}
tmp = __allocate_fw_buf(fw_name, fwc);
if (tmp)
list_add(&tmp->list, &fwc->head);
spin_unlock(&fwc->lock);
*buf = tmp;
return tmp ? 0 : -ENOMEM;
}
static struct firmware_buf *fw_lookup_buf(const char *fw_name)
{
struct firmware_buf *tmp;
struct firmware_cache *fwc = &fw_cache;
spin_lock(&fwc->lock);
tmp = __fw_lookup_buf(fw_name);
spin_unlock(&fwc->lock);
return tmp;
}
static void __fw_free_buf(struct kref *ref)
{
struct firmware_buf *buf = to_fwbuf(ref);
struct firmware_cache *fwc = buf->fwc;
pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
__func__, buf->fw_id, buf, buf->data,
(unsigned int)buf->size);
list_del(&buf->list);
spin_unlock(&fwc->lock);
#ifdef CONFIG_FW_LOADER_USER_HELPER
if (buf->is_paged_buf) {
int i;
vunmap(buf->data);
for (i = 0; i < buf->nr_pages; i++)
__free_page(buf->pages[i]);
kfree(buf->pages);
} else
#endif
vfree(buf->data);
kfree(buf);
}
static void fw_free_buf(struct firmware_buf *buf)
{
struct firmware_cache *fwc = buf->fwc;
spin_lock(&fwc->lock);
if (!kref_put(&buf->ref, __fw_free_buf))
spin_unlock(&fwc->lock);
}
/* direct firmware loading support */
static char fw_path_para[256];
static const char * const fw_path[] = {
fw_path_para,
"/lib/firmware/updates/" UTS_RELEASE,
"/lib/firmware/updates",
"/lib/firmware/" UTS_RELEASE,
"/lib/firmware"
};
/*
* Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
* from kernel command line because firmware_class is generally built in
* kernel instead of module.
*/
module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
/* Don't inline this: 'struct kstat' is biggish */
static noinline_for_stack long fw_file_size(struct file *file)
{
struct kstat st;
if (vfs_getattr(&file->f_path, &st))
return -1;
if (!S_ISREG(st.mode))
return -1;
if (st.size != (long)st.size)
return -1;
return st.size;
}
static bool fw_read_file_contents(struct file *file, struct firmware_buf *fw_buf)
{
long size;
char *buf;
size = fw_file_size(file);
if (size <= 0)
return false;
buf = vmalloc(size);
if (!buf)
return false;
if (kernel_read(file, 0, buf, size) != size) {
vfree(buf);
return false;
}
fw_buf->data = buf;
fw_buf->size = size;
return true;
}
static bool fw_get_filesystem_firmware(struct device *device,
struct firmware_buf *buf)
{
int i;
bool success = false;
char *path = __getname();
for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
struct file *file;
/* skip the unset customized path */
if (!fw_path[i][0])
continue;
snprintf(path, PATH_MAX, "%s/%s", fw_path[i], buf->fw_id);
file = filp_open(path, O_RDONLY, 0);
if (IS_ERR(file))
continue;
success = fw_read_file_contents(file, buf);
fput(file);
if (success)
break;
}
__putname(path);
if (success) {
dev_dbg(device, "firmware: direct-loading firmware %s\n",
buf->fw_id);
mutex_lock(&fw_lock);
set_bit(FW_STATUS_DONE, &buf->status);
complete_all(&buf->completion);
mutex_unlock(&fw_lock);
}
return success;
}
/* firmware holds the ownership of pages */
static void firmware_free_data(const struct firmware *fw)
{
/* Loaded directly? */
if (!fw->priv) {
vfree(fw->data);
return;
}
fw_free_buf(fw->priv);
}
/* store the pages buffer info firmware from buf */
static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw)
{
fw->priv = buf;
#ifdef CONFIG_FW_LOADER_USER_HELPER
fw->pages = buf->pages;
#endif
fw->size = buf->size;
fw->data = buf->data;
pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
__func__, buf->fw_id, buf, buf->data,
(unsigned int)buf->size);
}
#ifdef CONFIG_PM_SLEEP
static void fw_name_devm_release(struct device *dev, void *res)
{
struct fw_name_devm *fwn = res;
if (fwn->magic == (unsigned long)&fw_cache)
pr_debug("%s: fw_name-%s devm-%p released\n",
__func__, fwn->name, res);
}
static int fw_devm_match(struct device *dev, void *res,
void *match_data)
{
struct fw_name_devm *fwn = res;
return (fwn->magic == (unsigned long)&fw_cache) &&
!strcmp(fwn->name, match_data);
}
static struct fw_name_devm *fw_find_devm_name(struct device *dev,
const char *name)
{
struct fw_name_devm *fwn;
fwn = devres_find(dev, fw_name_devm_release,
fw_devm_match, (void *)name);
return fwn;
}
/* add firmware name into devres list */
static int fw_add_devm_name(struct device *dev, const char *name)
{
struct fw_name_devm *fwn;
fwn = fw_find_devm_name(dev, name);
if (fwn)
return 1;
fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm) +
strlen(name) + 1, GFP_KERNEL);
if (!fwn)
return -ENOMEM;
fwn->magic = (unsigned long)&fw_cache;
strcpy(fwn->name, name);
devres_add(dev, fwn);
return 0;
}
#else
static int fw_add_devm_name(struct device *dev, const char *name)
{
return 0;
}
#endif
/*
* user-mode helper code
*/
#ifdef CONFIG_FW_LOADER_USER_HELPER
struct firmware_priv {
struct delayed_work timeout_work;
bool nowait;
struct device dev;
struct firmware_buf *buf;
struct firmware *fw;
};
static struct firmware_priv *to_firmware_priv(struct device *dev)
{
return container_of(dev, struct firmware_priv, dev);
}
static void __fw_load_abort(struct firmware_buf *buf)
{
/*
* There is a small window in which user can write to 'loading'
* between loading done and disappearance of 'loading'
*/
if (test_bit(FW_STATUS_DONE, &buf->status))
return;
list_del_init(&buf->pending_list);
set_bit(FW_STATUS_ABORT, &buf->status);
complete_all(&buf->completion);
}
static void fw_load_abort(struct firmware_priv *fw_priv)
{
struct firmware_buf *buf = fw_priv->buf;
__fw_load_abort(buf);
/* avoid user action after loading abort */
fw_priv->buf = NULL;
}
#define is_fw_load_aborted(buf) \
test_bit(FW_STATUS_ABORT, &(buf)->status)
static LIST_HEAD(pending_fw_head);
/* reboot notifier for avoid deadlock with usermode_lock */
static int fw_shutdown_notify(struct notifier_block *unused1,
unsigned long unused2, void *unused3)
{
mutex_lock(&fw_lock);
while (!list_empty(&pending_fw_head))
__fw_load_abort(list_first_entry(&pending_fw_head,
struct firmware_buf,
pending_list));
mutex_unlock(&fw_lock);
return NOTIFY_DONE;
}
static struct notifier_block fw_shutdown_nb = {
.notifier_call = fw_shutdown_notify,
};
static ssize_t firmware_timeout_show(struct class *class,
struct class_attribute *attr,
char *buf)
{
return sprintf(buf, "%d\n", loading_timeout);
}
/**
* firmware_timeout_store - set number of seconds to wait for firmware
* @class: device class pointer
* @attr: device attribute pointer
* @buf: buffer to scan for timeout value
* @count: number of bytes in @buf
*
* Sets the number of seconds to wait for the firmware. Once
* this expires an error will be returned to the driver and no
* firmware will be provided.
*
* Note: zero means 'wait forever'.
**/
static ssize_t firmware_timeout_store(struct class *class,
struct class_attribute *attr,
const char *buf, size_t count)
{
loading_timeout = simple_strtol(buf, NULL, 10);
if (loading_timeout < 0)
loading_timeout = 0;
return count;
}
static struct class_attribute firmware_class_attrs[] = {
__ATTR(timeout, S_IWUSR | S_IRUGO,
firmware_timeout_show, firmware_timeout_store),
__ATTR_NULL
};
static void fw_dev_release(struct device *dev)
{
struct firmware_priv *fw_priv = to_firmware_priv(dev);
kfree(fw_priv);
module_put(THIS_MODULE);
}
static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
{
struct firmware_priv *fw_priv = to_firmware_priv(dev);
if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->buf->fw_id))
return -ENOMEM;
if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
return -ENOMEM;
if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
return -ENOMEM;
return 0;
}
static struct class firmware_class = {
.name = "firmware",
.class_attrs = firmware_class_attrs,
.dev_uevent = firmware_uevent,
.dev_release = fw_dev_release,
};
static ssize_t firmware_loading_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct firmware_priv *fw_priv = to_firmware_priv(dev);
int loading = 0;
mutex_lock(&fw_lock);
if (fw_priv->buf)
loading = test_bit(FW_STATUS_LOADING, &fw_priv->buf->status);
mutex_unlock(&fw_lock);
return sprintf(buf, "%d\n", loading);
}
/* Some architectures don't have PAGE_KERNEL_RO */
#ifndef PAGE_KERNEL_RO
#define PAGE_KERNEL_RO PAGE_KERNEL
#endif
/* one pages buffer should be mapped/unmapped only once */
static int fw_map_pages_buf(struct firmware_buf *buf)
{
if (!buf->is_paged_buf)
return 0;
if (buf->data)
vunmap(buf->data);
buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
if (!buf->data)
return -ENOMEM;
return 0;
}
/**
* firmware_loading_store - set value in the 'loading' control file
* @dev: device pointer
* @attr: device attribute pointer
* @buf: buffer to scan for loading control value
* @count: number of bytes in @buf
*
* The relevant values are:
*
* 1: Start a load, discarding any previous partial load.
* 0: Conclude the load and hand the data to the driver code.
* -1: Conclude the load with an error and discard any written data.
**/
static ssize_t firmware_loading_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct firmware_priv *fw_priv = to_firmware_priv(dev);
struct firmware_buf *fw_buf;
int loading = simple_strtol(buf, NULL, 10);
int i;
mutex_lock(&fw_lock);
fw_buf = fw_priv->buf;
if (!fw_buf)
goto out;
switch (loading) {
case 1:
/* discarding any previous partial load */
if (!test_bit(FW_STATUS_DONE, &fw_buf->status)) {
for (i = 0; i < fw_buf->nr_pages; i++)
__free_page(fw_buf->pages[i]);
kfree(fw_buf->pages);
fw_buf->pages = NULL;
fw_buf->page_array_size = 0;
fw_buf->nr_pages = 0;
set_bit(FW_STATUS_LOADING, &fw_buf->status);
}
break;
case 0:
if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) {
set_bit(FW_STATUS_DONE, &fw_buf->status);
clear_bit(FW_STATUS_LOADING, &fw_buf->status);
/*
* Several loading requests may be pending on
* one same firmware buf, so let all requests
* see the mapped 'buf->data' once the loading
* is completed.
* */
fw_map_pages_buf(fw_buf);
list_del_init(&fw_buf->pending_list);
complete_all(&fw_buf->completion);
break;
}
/* fallthrough */
default:
dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
/* fallthrough */
case -1:
fw_load_abort(fw_priv);
break;
}
out:
mutex_unlock(&fw_lock);
return count;
}
static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
struct bin_attribute *bin_attr,
char *buffer, loff_t offset, size_t count)
{
struct device *dev = kobj_to_dev(kobj);
struct firmware_priv *fw_priv = to_firmware_priv(dev);
struct firmware_buf *buf;
ssize_t ret_count;
mutex_lock(&fw_lock);
buf = fw_priv->buf;
if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
ret_count = -ENODEV;
goto out;
}
if (offset > buf->size) {
ret_count = 0;
goto out;
}
if (count > buf->size - offset)
count = buf->size - offset;
ret_count = count;
while (count) {
void *page_data;
int page_nr = offset >> PAGE_SHIFT;
int page_ofs = offset & (PAGE_SIZE-1);
int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
page_data = kmap(buf->pages[page_nr]);
memcpy(buffer, page_data + page_ofs, page_cnt);
kunmap(buf->pages[page_nr]);
buffer += page_cnt;
offset += page_cnt;
count -= page_cnt;
}
out:
mutex_unlock(&fw_lock);
return ret_count;
}
static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
{
struct firmware_buf *buf = fw_priv->buf;
int pages_needed = ALIGN(min_size, PAGE_SIZE) >> PAGE_SHIFT;
/* If the array of pages is too small, grow it... */
if (buf->page_array_size < pages_needed) {
int new_array_size = max(pages_needed,
buf->page_array_size * 2);
struct page **new_pages;
new_pages = kmalloc(new_array_size * sizeof(void *),
GFP_KERNEL);
if (!new_pages) {
fw_load_abort(fw_priv);
return -ENOMEM;
}
memcpy(new_pages, buf->pages,
buf->page_array_size * sizeof(void *));
memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
(new_array_size - buf->page_array_size));
kfree(buf->pages);
buf->pages = new_pages;
buf->page_array_size = new_array_size;
}
while (buf->nr_pages < pages_needed) {
buf->pages[buf->nr_pages] =
alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
if (!buf->pages[buf->nr_pages]) {
fw_load_abort(fw_priv);
return -ENOMEM;
}
buf->nr_pages++;
}
return 0;
}
/**
* firmware_data_write - write method for firmware
* @filp: open sysfs file
* @kobj: kobject for the device
* @bin_attr: bin_attr structure
* @buffer: buffer being written
* @offset: buffer offset for write in total data store area
* @count: buffer size
*
* Data written to the 'data' attribute will be later handed to
* the driver as a firmware image.
**/
static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
struct bin_attribute *bin_attr,
char *buffer, loff_t offset, size_t count)
{
struct device *dev = kobj_to_dev(kobj);
struct firmware_priv *fw_priv = to_firmware_priv(dev);
struct firmware_buf *buf;
ssize_t retval;
if (!capable(CAP_SYS_RAWIO))
return -EPERM;
mutex_lock(&fw_lock);
buf = fw_priv->buf;
if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
retval = -ENODEV;
goto out;
}
retval = fw_realloc_buffer(fw_priv, offset + count);
if (retval)
goto out;
retval = count;
while (count) {
void *page_data;
int page_nr = offset >> PAGE_SHIFT;
int page_ofs = offset & (PAGE_SIZE - 1);
int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
page_data = kmap(buf->pages[page_nr]);
memcpy(page_data + page_ofs, buffer, page_cnt);
kunmap(buf->pages[page_nr]);
buffer += page_cnt;
offset += page_cnt;
count -= page_cnt;
}
buf->size = max_t(size_t, offset, buf->size);
out:
mutex_unlock(&fw_lock);
return retval;
}
static struct bin_attribute firmware_attr_data = {
.attr = { .name = "data", .mode = 0644 },
.size = 0,
.read = firmware_data_read,
.write = firmware_data_write,
};
static void firmware_class_timeout_work(struct work_struct *work)
{
struct firmware_priv *fw_priv = container_of(work,
struct firmware_priv, timeout_work.work);
mutex_lock(&fw_lock);
fw_load_abort(fw_priv);
mutex_unlock(&fw_lock);
}
static struct firmware_priv *
fw_create_instance(struct firmware *firmware, const char *fw_name,
struct device *device, bool uevent, bool nowait)
{
struct firmware_priv *fw_priv;
struct device *f_dev;
fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
if (!fw_priv) {
dev_err(device, "%s: kmalloc failed\n", __func__);
fw_priv = ERR_PTR(-ENOMEM);
goto exit;
}
fw_priv->nowait = nowait;
fw_priv->fw = firmware;
INIT_DELAYED_WORK(&fw_priv->timeout_work,
firmware_class_timeout_work);
f_dev = &fw_priv->dev;
device_initialize(f_dev);
dev_set_name(f_dev, "%s", fw_name);
f_dev->parent = device;
f_dev->class = &firmware_class;
exit:
return fw_priv;
}
/* load a firmware via user helper */
static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
long timeout)
{
int retval = 0;
struct device *f_dev = &fw_priv->dev;
struct firmware_buf *buf = fw_priv->buf;
/* fall back on userspace loading */
buf->is_paged_buf = true;
dev_set_uevent_suppress(f_dev, true);
/* Need to pin this module until class device is destroyed */
__module_get(THIS_MODULE);
retval = device_add(f_dev);
if (retval) {
dev_err(f_dev, "%s: device_register failed\n", __func__);
goto err_put_dev;
}
retval = device_create_bin_file(f_dev, &firmware_attr_data);
if (retval) {
dev_err(f_dev, "%s: sysfs_create_bin_file failed\n", __func__);
goto err_del_dev;
}
mutex_lock(&fw_lock);
list_add(&buf->pending_list, &pending_fw_head);
mutex_unlock(&fw_lock);
retval = device_create_file(f_dev, &dev_attr_loading);
if (retval) {
mutex_lock(&fw_lock);
list_del_init(&buf->pending_list);
mutex_unlock(&fw_lock);
dev_err(f_dev, "%s: device_create_file failed\n", __func__);
goto err_del_bin_attr;
}
if (uevent) {
dev_set_uevent_suppress(f_dev, false);
dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
if (timeout != MAX_SCHEDULE_TIMEOUT)
schedule_delayed_work(&fw_priv->timeout_work, timeout);
kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
}
wait_for_completion(&buf->completion);
cancel_delayed_work_sync(&fw_priv->timeout_work);
device_remove_file(f_dev, &dev_attr_loading);
err_del_bin_attr:
device_remove_bin_file(f_dev, &firmware_attr_data);
err_del_dev:
device_del(f_dev);
err_put_dev:
put_device(f_dev);
return retval;
}
static int fw_load_from_user_helper(struct firmware *firmware,
const char *name, struct device *device,
bool uevent, bool nowait, long timeout)
{
struct firmware_priv *fw_priv;
fw_priv = fw_create_instance(firmware, name, device, uevent, nowait);
if (IS_ERR(fw_priv))
return PTR_ERR(fw_priv);
fw_priv->buf = firmware->priv;
return _request_firmware_load(fw_priv, uevent, timeout);
}
#else /* CONFIG_FW_LOADER_USER_HELPER */
static inline int
fw_load_from_user_helper(struct firmware *firmware, const char *name,
struct device *device, bool uevent, bool nowait,
long timeout)
{
return -ENOENT;
}
/* No abort during direct loading */
#define is_fw_load_aborted(buf) false
#endif /* CONFIG_FW_LOADER_USER_HELPER */
/* wait until the shared firmware_buf becomes ready (or error) */
static int sync_cached_firmware_buf(struct firmware_buf *buf)
{
int ret = 0;
mutex_lock(&fw_lock);
while (!test_bit(FW_STATUS_DONE, &buf->status)) {
if (is_fw_load_aborted(buf)) {
ret = -ENOENT;
break;
}
mutex_unlock(&fw_lock);
wait_for_completion(&buf->completion);
mutex_lock(&fw_lock);
}
mutex_unlock(&fw_lock);
return ret;
}
/* prepare firmware and firmware_buf structs;
* return 0 if a firmware is already assigned, 1 if need to load one,
* or a negative error code
*/
static int
_request_firmware_prepare(struct firmware **firmware_p, const char *name,
struct device *device)
{
struct firmware *firmware;
struct firmware_buf *buf;
int ret;
*firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
if (!firmware) {
dev_err(device, "%s: kmalloc(struct firmware) failed\n",
__func__);
return -ENOMEM;
}
if (fw_get_builtin_firmware(firmware, name)) {
dev_dbg(device, "firmware: using built-in firmware %s\n", name);
return 0; /* assigned */
}
ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf);
/*
* bind with 'buf' now to avoid warning in failure path
* of requesting firmware.
*/
firmware->priv = buf;
if (ret > 0) {
ret = sync_cached_firmware_buf(buf);
if (!ret) {
fw_set_page_data(buf, firmware);
return 0; /* assigned */
}
}
if (ret < 0)
return ret;
return 1; /* need to load */
}
static int assign_firmware_buf(struct firmware *fw, struct device *device)
{
struct firmware_buf *buf = fw->priv;
mutex_lock(&fw_lock);
if (!buf->size || is_fw_load_aborted(buf)) {
mutex_unlock(&fw_lock);
return -ENOENT;
}
/*
* add firmware name into devres list so that we can auto cache
* and uncache firmware for device.
*
* device may has been deleted already, but the problem
* should be fixed in devres or driver core.
*/
if (device)
fw_add_devm_name(device, buf->fw_id);
/*
* After caching firmware image is started, let it piggyback
* on request firmware.
*/
if (buf->fwc->state == FW_LOADER_START_CACHE) {
if (fw_cache_piggyback_on_request(buf->fw_id))
kref_get(&buf->ref);
}
/* pass the pages buffer to driver at the last minute */
fw_set_page_data(buf, fw);
mutex_unlock(&fw_lock);
return 0;
}
/* called from request_firmware() and request_firmware_work_func() */
static int
_request_firmware(const struct firmware **firmware_p, const char *name,
struct device *device, bool uevent, bool nowait)
{
struct firmware *fw;
long timeout;
int ret;
if (!firmware_p)
return -EINVAL;
ret = _request_firmware_prepare(&fw, name, device);
if (ret <= 0) /* error or already assigned */
goto out;
ret = 0;
timeout = firmware_loading_timeout();
if (nowait) {
timeout = usermodehelper_read_lock_wait(timeout);
if (!timeout) {
dev_dbg(device, "firmware: %s loading timed out\n",
name);
ret = -EBUSY;
goto out;
}
} else {
ret = usermodehelper_read_trylock();
if (WARN_ON(ret)) {
dev_err(device, "firmware: %s will not be loaded\n",
name);
goto out;
}
}
if (!fw_get_filesystem_firmware(device, fw->priv))
ret = fw_load_from_user_helper(fw, name, device,
uevent, nowait, timeout);
if (!ret)
ret = assign_firmware_buf(fw, device);
usermodehelper_read_unlock();
out:
if (ret < 0) {
release_firmware(fw);
fw = NULL;
}
*firmware_p = fw;
return ret;
}
/**
* request_firmware: - send firmware request and wait for it
* @firmware_p: pointer to firmware image
* @name: name of firmware file
* @device: device for which firmware is being loaded
*
* @firmware_p will be used to return a firmware image by the name
* of @name for device @device.
*
* Should be called from user context where sleeping is allowed.
*
* @name will be used as $FIRMWARE in the uevent environment and
* should be distinctive enough not to be confused with any other
* firmware image for this or any other device.
*
* Caller must hold the reference count of @device.
*
* The function can be called safely inside device's suspend and
* resume callback.
**/
int
request_firmware(const struct firmware **firmware_p, const char *name,
struct device *device)
{
return _request_firmware(firmware_p, name, device, true, false);
}
/**
* release_firmware: - release the resource associated with a firmware image
* @fw: firmware resource to release
**/
void release_firmware(const struct firmware *fw)
{
if (fw) {
if (!fw_is_builtin_firmware(fw))
firmware_free_data(fw);
kfree(fw);
}
}
/* Async support */
struct firmware_work {
struct work_struct work;
struct module *module;
const char *name;
struct device *device;
void *context;
void (*cont)(const struct firmware *fw, void *context);
bool uevent;
};
static void request_firmware_work_func(struct work_struct *work)
{
struct firmware_work *fw_work;
const struct firmware *fw;
fw_work = container_of(work, struct firmware_work, work);
_request_firmware(&fw, fw_work->name, fw_work->device,
fw_work->uevent, true);
fw_work->cont(fw, fw_work->context);
put_device(fw_work->device); /* taken in request_firmware_nowait() */
module_put(fw_work->module);
kfree(fw_work);
}
/**
* request_firmware_nowait - asynchronous version of request_firmware
* @module: module requesting the firmware
* @uevent: sends uevent to copy the firmware image if this flag
* is non-zero else the firmware copy must be done manually.
* @name: name of firmware file
* @device: device for which firmware is being loaded
* @gfp: allocation flags
* @context: will be passed over to @cont, and
* @fw may be %NULL if firmware request fails.
* @cont: function will be called asynchronously when the firmware
* request is over.
*
* Caller must hold the reference count of @device.
*
* Asynchronous variant of request_firmware() for user contexts:
* - sleep for as small periods as possible since it may
* increase kernel boot time of built-in device drivers
* requesting firmware in their ->probe() methods, if
* @gfp is GFP_KERNEL.
*
* - can't sleep at all if @gfp is GFP_ATOMIC.
**/
int
request_firmware_nowait(
struct module *module, bool uevent,
const char *name, struct device *device, gfp_t gfp, void *context,
void (*cont)(const struct firmware *fw, void *context))
{
struct firmware_work *fw_work;
fw_work = kzalloc(sizeof (struct firmware_work), gfp);
if (!fw_work)
return -ENOMEM;
fw_work->module = module;
fw_work->name = name;
fw_work->device = device;
fw_work->context = context;
fw_work->cont = cont;
fw_work->uevent = uevent;
if (!try_module_get(module)) {
kfree(fw_work);
return -EFAULT;
}
get_device(fw_work->device);
INIT_WORK(&fw_work->work, request_firmware_work_func);
schedule_work(&fw_work->work);
return 0;
}
/**
* cache_firmware - cache one firmware image in kernel memory space
* @fw_name: the firmware image name
*
* Cache firmware in kernel memory so that drivers can use it when
* system isn't ready for them to request firmware image from userspace.
* Once it returns successfully, driver can use request_firmware or its
* nowait version to get the cached firmware without any interacting
* with userspace
*
* Return 0 if the firmware image has been cached successfully
* Return !0 otherwise
*
*/
int cache_firmware(const char *fw_name)
{
int ret;
const struct firmware *fw;
pr_debug("%s: %s\n", __func__, fw_name);
ret = request_firmware(&fw, fw_name, NULL);
if (!ret)
kfree(fw);
pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
return ret;
}
/**
* uncache_firmware - remove one cached firmware image
* @fw_name: the firmware image name
*
* Uncache one firmware image which has been cached successfully
* before.
*
* Return 0 if the firmware cache has been removed successfully
* Return !0 otherwise
*
*/
int uncache_firmware(const char *fw_name)
{
struct firmware_buf *buf;
struct firmware fw;
pr_debug("%s: %s\n", __func__, fw_name);
if (fw_get_builtin_firmware(&fw, fw_name))
return 0;
buf = fw_lookup_buf(fw_name);
if (buf) {
fw_free_buf(buf);
return 0;
}
return -EINVAL;
}
#ifdef CONFIG_PM_SLEEP
static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
{
struct fw_cache_entry *fce;
fce = kzalloc(sizeof(*fce) + strlen(name) + 1, GFP_ATOMIC);
if (!fce)
goto exit;
strcpy(fce->name, name);
exit:
return fce;
}
static int __fw_entry_found(const char *name)
{
struct firmware_cache *fwc = &fw_cache;
struct fw_cache_entry *fce;
list_for_each_entry(fce, &fwc->fw_names, list) {
if (!strcmp(fce->name, name))
return 1;
}
return 0;
}
static int fw_cache_piggyback_on_request(const char *name)
{
struct firmware_cache *fwc = &fw_cache;
struct fw_cache_entry *fce;
int ret = 0;
spin_lock(&fwc->name_lock);
if (__fw_entry_found(name))
goto found;
fce = alloc_fw_cache_entry(name);
if (fce) {
ret = 1;
list_add(&fce->list, &fwc->fw_names);
pr_debug("%s: fw: %s\n", __func__, name);
}
found:
spin_unlock(&fwc->name_lock);
return ret;
}
static void free_fw_cache_entry(struct fw_cache_entry *fce)
{
kfree(fce);
}
static void __async_dev_cache_fw_image(void *fw_entry,
async_cookie_t cookie)
{
struct fw_cache_entry *fce = fw_entry;
struct firmware_cache *fwc = &fw_cache;
int ret;
ret = cache_firmware(fce->name);
if (ret) {
spin_lock(&fwc->name_lock);
list_del(&fce->list);
spin_unlock(&fwc->name_lock);
free_fw_cache_entry(fce);
}
}
/* called with dev->devres_lock held */
static void dev_create_fw_entry(struct device *dev, void *res,
void *data)
{
struct fw_name_devm *fwn = res;
const char *fw_name = fwn->name;
struct list_head *head = data;
struct fw_cache_entry *fce;
fce = alloc_fw_cache_entry(fw_name);
if (fce)
list_add(&fce->list, head);
}
static int devm_name_match(struct device *dev, void *res,
void *match_data)
{
struct fw_name_devm *fwn = res;
return (fwn->magic == (unsigned long)match_data);
}
static void dev_cache_fw_image(struct device *dev, void *data)
{
LIST_HEAD(todo);
struct fw_cache_entry *fce;
struct fw_cache_entry *fce_next;
struct firmware_cache *fwc = &fw_cache;
devres_for_each_res(dev, fw_name_devm_release,
devm_name_match, &fw_cache,
dev_create_fw_entry, &todo);
list_for_each_entry_safe(fce, fce_next, &todo, list) {
list_del(&fce->list);
spin_lock(&fwc->name_lock);
/* only one cache entry for one firmware */
if (!__fw_entry_found(fce->name)) {
list_add(&fce->list, &fwc->fw_names);
} else {
free_fw_cache_entry(fce);
fce = NULL;
}
spin_unlock(&fwc->name_lock);
if (fce)
async_schedule_domain(__async_dev_cache_fw_image,
(void *)fce,
&fw_cache_domain);
}
}
static void __device_uncache_fw_images(void)
{
struct firmware_cache *fwc = &fw_cache;
struct fw_cache_entry *fce;
spin_lock(&fwc->name_lock);
while (!list_empty(&fwc->fw_names)) {
fce = list_entry(fwc->fw_names.next,
struct fw_cache_entry, list);
list_del(&fce->list);
spin_unlock(&fwc->name_lock);
uncache_firmware(fce->name);
free_fw_cache_entry(fce);
spin_lock(&fwc->name_lock);
}
spin_unlock(&fwc->name_lock);
}
/**
* device_cache_fw_images - cache devices' firmware
*
* If one device called request_firmware or its nowait version
* successfully before, the firmware names are recored into the
* device's devres link list, so device_cache_fw_images can call
* cache_firmware() to cache these firmwares for the device,
* then the device driver can load its firmwares easily at
* time when system is not ready to complete loading firmware.
*/
static void device_cache_fw_images(void)
{
struct firmware_cache *fwc = &fw_cache;
int old_timeout;
DEFINE_WAIT(wait);
pr_debug("%s\n", __func__);
/* cancel uncache work */
cancel_delayed_work_sync(&fwc->work);
/*
* use small loading timeout for caching devices' firmware
* because all these firmware images have been loaded
* successfully at lease once, also system is ready for
* completing firmware loading now. The maximum size of
* firmware in current distributions is about 2M bytes,
* so 10 secs should be enough.
*/
old_timeout = loading_timeout;
loading_timeout = 10;
mutex_lock(&fw_lock);
fwc->state = FW_LOADER_START_CACHE;
dpm_for_each_dev(NULL, dev_cache_fw_image);
mutex_unlock(&fw_lock);
/* wait for completion of caching firmware for all devices */
async_synchronize_full_domain(&fw_cache_domain);
loading_timeout = old_timeout;
}
/**
* device_uncache_fw_images - uncache devices' firmware
*
* uncache all firmwares which have been cached successfully
* by device_uncache_fw_images earlier
*/
static void device_uncache_fw_images(void)
{
pr_debug("%s\n", __func__);
__device_uncache_fw_images();
}
static void device_uncache_fw_images_work(struct work_struct *work)
{
device_uncache_fw_images();
}
/**
* device_uncache_fw_images_delay - uncache devices firmwares
* @delay: number of milliseconds to delay uncache device firmwares
*
* uncache all devices's firmwares which has been cached successfully
* by device_cache_fw_images after @delay milliseconds.
*/
static void device_uncache_fw_images_delay(unsigned long delay)
{
schedule_delayed_work(&fw_cache.work,
msecs_to_jiffies(delay));
}
static int fw_pm_notify(struct notifier_block *notify_block,
unsigned long mode, void *unused)
{
switch (mode) {
case PM_HIBERNATION_PREPARE:
case PM_SUSPEND_PREPARE:
device_cache_fw_images();
break;
case PM_POST_SUSPEND:
case PM_POST_HIBERNATION:
case PM_POST_RESTORE:
/*
* In case that system sleep failed and syscore_suspend is
* not called.
*/
mutex_lock(&fw_lock);
fw_cache.state = FW_LOADER_NO_CACHE;
mutex_unlock(&fw_lock);
device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
break;
}
return 0;
}
/* stop caching firmware once syscore_suspend is reached */
static int fw_suspend(void)
{
fw_cache.state = FW_LOADER_NO_CACHE;
return 0;
}
static struct syscore_ops fw_syscore_ops = {
.suspend = fw_suspend,
};
#else
static int fw_cache_piggyback_on_request(const char *name)
{
return 0;
}
#endif
static void __init fw_cache_init(void)
{
spin_lock_init(&fw_cache.lock);
INIT_LIST_HEAD(&fw_cache.head);
fw_cache.state = FW_LOADER_NO_CACHE;
#ifdef CONFIG_PM_SLEEP
spin_lock_init(&fw_cache.name_lock);
INIT_LIST_HEAD(&fw_cache.fw_names);
INIT_DELAYED_WORK(&fw_cache.work,
device_uncache_fw_images_work);
fw_cache.pm_notify.notifier_call = fw_pm_notify;
register_pm_notifier(&fw_cache.pm_notify);
register_syscore_ops(&fw_syscore_ops);
#endif
}
static int __init firmware_class_init(void)
{
fw_cache_init();
#ifdef CONFIG_FW_LOADER_USER_HELPER
register_reboot_notifier(&fw_shutdown_nb);
return class_register(&firmware_class);
#else
return 0;
#endif
}
static void __exit firmware_class_exit(void)
{
#ifdef CONFIG_PM_SLEEP
unregister_syscore_ops(&fw_syscore_ops);
unregister_pm_notifier(&fw_cache.pm_notify);
#endif
#ifdef CONFIG_FW_LOADER_USER_HELPER
unregister_reboot_notifier(&fw_shutdown_nb);
class_unregister(&firmware_class);
#endif
}
fs_initcall(firmware_class_init);
module_exit(firmware_class_exit);
EXPORT_SYMBOL(release_firmware);
EXPORT_SYMBOL(request_firmware);
EXPORT_SYMBOL(request_firmware_nowait);
EXPORT_SYMBOL_GPL(cache_firmware);
EXPORT_SYMBOL_GPL(uncache_firmware);