diff options
| -rw-r--r-- | drivers/base/Makefile | 4 | ||||
| -rw-r--r-- | drivers/base/firmware_fallback.c | 661 | ||||
| -rw-r--r-- | drivers/base/firmware_fallback.h | 61 | ||||
| -rw-r--r-- | drivers/base/firmware_fallback_table.c | 29 | ||||
| -rw-r--r-- | drivers/base/firmware_loader.c | 803 | ||||
| -rw-r--r-- | drivers/base/firmware_loader.h | 115 |
6 files changed, 874 insertions, 799 deletions
diff --git a/drivers/base/Makefile b/drivers/base/Makefile index f261143fafbf..b946a408256d 100644 --- a/drivers/base/Makefile +++ b/drivers/base/Makefile @@ -5,7 +5,8 @@ obj-y := component.o core.o bus.o dd.o syscore.o \ driver.o class.o platform.o \ cpu.o firmware.o init.o map.o devres.o \ attribute_container.o transport_class.o \ - topology.o container.o property.o cacheinfo.o + topology.o container.o property.o cacheinfo.o \ + firmware_fallback_table.o obj-$(CONFIG_DEVTMPFS) += devtmpfs.o obj-$(CONFIG_DMA_CMA) += dma-contiguous.o obj-y += power/ @@ -14,6 +15,7 @@ obj-$(CONFIG_HAVE_GENERIC_DMA_COHERENT) += dma-coherent.o obj-$(CONFIG_ISA_BUS_API) += isa.o obj-$(CONFIG_FW_LOADER) += firmware_class.o firmware_class-objs := firmware_loader.o +firmware_class-$(CONFIG_FW_LOADER_USER_HELPER) += firmware_fallback.o obj-$(CONFIG_NUMA) += node.o obj-$(CONFIG_MEMORY_HOTPLUG_SPARSE) += memory.o ifeq ($(CONFIG_SYSFS),y) diff --git a/drivers/base/firmware_fallback.c b/drivers/base/firmware_fallback.c new file mode 100644 index 000000000000..47690207e0ee --- /dev/null +++ b/drivers/base/firmware_fallback.c @@ -0,0 +1,661 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/types.h> +#include <linux/kconfig.h> +#include <linux/list.h> +#include <linux/slab.h> +#include <linux/security.h> +#include <linux/highmem.h> +#include <linux/umh.h> + +#include "firmware_fallback.h" +#include "firmware_loader.h" + +/* + * firmware fallback mechanism + */ + +extern struct firmware_fallback_config fw_fallback_config; + +/* These getters are vetted to use int properly */ +static inline int __firmware_loading_timeout(void) +{ + return fw_fallback_config.loading_timeout; +} + +/* These setters are vetted to use int properly */ +static void __fw_fallback_set_timeout(int timeout) +{ + fw_fallback_config.loading_timeout = timeout; +} + +/* + * 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. + */ +void fw_fallback_set_cache_timeout(void) +{ + fw_fallback_config.old_timeout = __firmware_loading_timeout(); + __fw_fallback_set_timeout(10); +} + +/* Restores the timeout to the value last configured during normal operation */ +void fw_fallback_set_default_timeout(void) +{ + __fw_fallback_set_timeout(fw_fallback_config.old_timeout); +} + +static long firmware_loading_timeout(void) +{ + return __firmware_loading_timeout() > 0 ? + __firmware_loading_timeout() * HZ : MAX_JIFFY_OFFSET; +} + +static inline bool fw_sysfs_done(struct fw_priv *fw_priv) +{ + return __fw_state_check(fw_priv, FW_STATUS_DONE); +} + +static inline bool fw_sysfs_loading(struct fw_priv *fw_priv) +{ + return __fw_state_check(fw_priv, FW_STATUS_LOADING); +} + +static inline int fw_sysfs_wait_timeout(struct fw_priv *fw_priv, long timeout) +{ + return __fw_state_wait_common(fw_priv, timeout); +} + +struct fw_sysfs { + bool nowait; + struct device dev; + struct fw_priv *fw_priv; + struct firmware *fw; +}; + +static struct fw_sysfs *to_fw_sysfs(struct device *dev) +{ + return container_of(dev, struct fw_sysfs, dev); +} + +static void __fw_load_abort(struct fw_priv *fw_priv) +{ + /* + * There is a small window in which user can write to 'loading' + * between loading done and disappearance of 'loading' + */ + if (fw_sysfs_done(fw_priv)) + return; + + list_del_init(&fw_priv->pending_list); + fw_state_aborted(fw_priv); +} + +static void fw_load_abort(struct fw_sysfs *fw_sysfs) +{ + struct fw_priv *fw_priv = fw_sysfs->fw_priv; + + __fw_load_abort(fw_priv); +} + +static LIST_HEAD(pending_fw_head); + +void kill_pending_fw_fallback_reqs(bool only_kill_custom) +{ + struct fw_priv *fw_priv; + struct fw_priv *next; + + mutex_lock(&fw_lock); + list_for_each_entry_safe(fw_priv, next, &pending_fw_head, + pending_list) { + if (!fw_priv->need_uevent || !only_kill_custom) + __fw_load_abort(fw_priv); + } + mutex_unlock(&fw_lock); +} + +static ssize_t timeout_show(struct class *class, struct class_attribute *attr, + char *buf) +{ + return sprintf(buf, "%d\n", __firmware_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 timeout_store(struct class *class, struct class_attribute *attr, + const char *buf, size_t count) +{ + int tmp_loading_timeout = simple_strtol(buf, NULL, 10); + + if (tmp_loading_timeout < 0) + tmp_loading_timeout = 0; + + __fw_fallback_set_timeout(tmp_loading_timeout); + + return count; +} +static CLASS_ATTR_RW(timeout); + +static struct attribute *firmware_class_attrs[] = { + &class_attr_timeout.attr, + NULL, +}; +ATTRIBUTE_GROUPS(firmware_class); + +static void fw_dev_release(struct device *dev) +{ + struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev); + + kfree(fw_sysfs); +} + +static int do_firmware_uevent(struct fw_sysfs *fw_sysfs, struct kobj_uevent_env *env) +{ + if (add_uevent_var(env, "FIRMWARE=%s", fw_sysfs->fw_priv->fw_name)) + return -ENOMEM; + if (add_uevent_var(env, "TIMEOUT=%i", __firmware_loading_timeout())) + return -ENOMEM; + if (add_uevent_var(env, "ASYNC=%d", fw_sysfs->nowait)) + return -ENOMEM; + + return 0; +} + +static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev); + int err = 0; + + mutex_lock(&fw_lock); + if (fw_sysfs->fw_priv) + err = do_firmware_uevent(fw_sysfs, env); + mutex_unlock(&fw_lock); + return err; +} + +static struct class firmware_class = { + .name = "firmware", + .class_groups = firmware_class_groups, + .dev_uevent = firmware_uevent, + .dev_release = fw_dev_release, +}; + +int register_sysfs_loader(void) +{ + return class_register(&firmware_class); +} + +void unregister_sysfs_loader(void) +{ + class_unregister(&firmware_class); +} + +static ssize_t firmware_loading_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev); + int loading = 0; + + mutex_lock(&fw_lock); + if (fw_sysfs->fw_priv) + loading = fw_sysfs_loading(fw_sysfs->fw_priv); + 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 map_fw_priv_pages(struct fw_priv *fw_priv) +{ + if (!fw_priv->is_paged_buf) + return 0; + + vunmap(fw_priv->data); + fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0, + PAGE_KERNEL_RO); + if (!fw_priv->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 fw_sysfs *fw_sysfs = to_fw_sysfs(dev); + struct fw_priv *fw_priv; + ssize_t written = count; + int loading = simple_strtol(buf, NULL, 10); + int i; + + mutex_lock(&fw_lock); + fw_priv = fw_sysfs->fw_priv; + if (fw_state_is_aborted(fw_priv)) + goto out; + + switch (loading) { + case 1: + /* discarding any previous partial load */ + if (!fw_sysfs_done(fw_priv)) { + for (i = 0; i < fw_priv->nr_pages; i++) + __free_page(fw_priv->pages[i]); + vfree(fw_priv->pages); + fw_priv->pages = NULL; + fw_priv->page_array_size = 0; + fw_priv->nr_pages = 0; + fw_state_start(fw_priv); + } + break; + case 0: + if (fw_sysfs_loading(fw_priv)) { + int rc; + + /* + * 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. + * */ + rc = map_fw_priv_pages(fw_priv); + if (rc) + dev_err(dev, "%s: map pages failed\n", + __func__); + else + rc = security_kernel_post_read_file(NULL, + fw_priv->data, fw_priv->size, + READING_FIRMWARE); + + /* + * Same logic as fw_load_abort, only the DONE bit + * is ignored and we set ABORT only on failure. + */ + list_del_init(&fw_priv->pending_list); + if (rc) { + fw_state_aborted(fw_priv); + written = rc; + } else { + fw_state_done(fw_priv); + } + break; + } + /* fallthrough */ + default: + dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading); + /* fallthrough */ + case -1: + fw_load_abort(fw_sysfs); + break; + } +out: + mutex_unlock(&fw_lock); + return written; +} + +static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store); + +static void firmware_rw_data(struct fw_priv *fw_priv, char *buffer, + loff_t offset, size_t count, bool read) +{ + if (read) + memcpy(buffer, fw_priv->data + offset, count); + else + memcpy(fw_priv->data + offset, buffer, count); +} + +static void firmware_rw(struct fw_priv *fw_priv, char *buffer, + loff_t offset, size_t count, bool read) +{ + 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(fw_priv->pages[page_nr]); + + if (read) + memcpy(buffer, page_data + page_ofs, page_cnt); + else + memcpy(page_data + page_ofs, buffer, page_cnt); + + kunmap(fw_priv->pages[page_nr]); + buffer += page_cnt; + offset += page_cnt; + count -= page_cnt; + } +} + +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 fw_sysfs *fw_sysfs = to_fw_sysfs(dev); + struct fw_priv *fw_priv; + ssize_t ret_count; + + mutex_lock(&fw_lock); + fw_priv = fw_sysfs->fw_priv; + if (!fw_priv || fw_sysfs_done(fw_priv)) { + ret_count = -ENODEV; + goto out; + } + if (offset > fw_priv->size) { + ret_count = 0; + goto out; + } + if (count > fw_priv->size - offset) + count = fw_priv->size - offset; + + ret_count = count; + + if (fw_priv->data) + firmware_rw_data(fw_priv, buffer, offset, count, true); + else + firmware_rw(fw_priv, buffer, offset, count, true); + +out: + mutex_unlock(&fw_lock); + return ret_count; +} + +static int fw_realloc_pages(struct fw_sysfs *fw_sysfs, int min_size) +{ + struct fw_priv *fw_priv= fw_sysfs->fw_priv; + int pages_needed = PAGE_ALIGN(min_size) >> PAGE_SHIFT; + + /* If the array of pages is too small, grow it... */ + if (fw_priv->page_array_size < pages_needed) { + int new_array_size = max(pages_needed, + fw_priv->page_array_size * 2); + struct page **new_pages; + + new_pages = vmalloc(new_array_size * sizeof(void *)); + if (!new_pages) { + fw_load_abort(fw_sysfs); + return -ENOMEM; + } + memcpy(new_pages, fw_priv->pages, + fw_priv->page_array_size * sizeof(void *)); + memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) * + (new_array_size - fw_priv->page_array_size)); + vfree(fw_priv->pages); + fw_priv->pages = new_pages; + fw_priv->page_array_size = new_array_size; + } + + while (fw_priv->nr_pages < pages_needed) { + fw_priv->pages[fw_priv->nr_pages] = + alloc_page(GFP_KERNEL | __GFP_HIGHMEM); + + if (!fw_priv->pages[fw_priv->nr_pages]) { + fw_load_abort(fw_sysfs); + return -ENOMEM; + } + fw_priv->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 fw_sysfs *fw_sysfs = to_fw_sysfs(dev); + struct fw_priv *fw_priv; + ssize_t retval; + + if (!capable(CAP_SYS_RAWIO)) + return -EPERM; + + mutex_lock(&fw_lock); + fw_priv = fw_sysfs->fw_priv; + if (!fw_priv || fw_sysfs_done(fw_priv)) { + retval = -ENODEV; + goto out; + } + + if (fw_priv->data) { + if (offset + count > fw_priv->allocated_size) { + retval = -ENOMEM; + goto out; + } + firmware_rw_data(fw_priv, buffer, offset, count, false); + retval = count; + } else { + retval = fw_realloc_pages(fw_sysfs, offset + count); + if (retval) + goto out; + + retval = count; + firmware_rw(fw_priv, buffer, offset, count, false); + } + + fw_priv->size = max_t(size_t, offset + count, fw_priv->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 struct attribute *fw_dev_attrs[] = { + &dev_attr_loading.attr, + NULL +}; + +static struct bin_attribute *fw_dev_bin_attrs[] = { + &firmware_attr_data, + NULL +}; + +static const struct attribute_group fw_dev_attr_group = { + .attrs = fw_dev_attrs, + .bin_attrs = fw_dev_bin_attrs, +}; + +static const struct attribute_group *fw_dev_attr_groups[] = { + &fw_dev_attr_group, + NULL +}; + +static struct fw_sysfs * +fw_create_instance(struct firmware *firmware, const char *fw_name, + struct device *device, unsigned int opt_flags) +{ + struct fw_sysfs *fw_sysfs; + struct device *f_dev; + + fw_sysfs = kzalloc(sizeof(*fw_sysfs), GFP_KERNEL); + if (!fw_sysfs) { + fw_sysfs = ERR_PTR(-ENOMEM); + goto exit; + } + + fw_sysfs->nowait = !!(opt_flags & FW_OPT_NOWAIT); + fw_sysfs->fw = firmware; + f_dev = &fw_sysfs->dev; + + device_initialize(f_dev); + dev_set_name(f_dev, "%s", fw_name); + f_dev->parent = device; + f_dev->class = &firmware_class; + f_dev->groups = fw_dev_attr_groups; +exit: + return fw_sysfs; +} + +/* load a firmware via user helper */ +static int _request_firmware_load(struct fw_sysfs *fw_sysfs, + unsigned int opt_flags, long timeout) +{ + int retval = 0; + struct device *f_dev = &fw_sysfs->dev; + struct fw_priv *fw_priv = fw_sysfs->fw_priv; + + /* fall back on userspace loading */ + if (!fw_priv->data) + fw_priv->is_paged_buf = true; + + dev_set_uevent_suppress(f_dev, true); + + retval = device_add(f_dev); + if (retval) { + dev_err(f_dev, "%s: device_register failed\n", __func__); + goto err_put_dev; + } + + mutex_lock(&fw_lock); + list_add(&fw_priv->pending_list, &pending_fw_head); + mutex_unlock(&fw_lock); + + if (opt_flags & FW_OPT_UEVENT) { + fw_priv->need_uevent = true; + dev_set_uevent_suppress(f_dev, false); + dev_dbg(f_dev, "firmware: requesting %s\n", fw_priv->fw_name); + kobject_uevent(&fw_sysfs->dev.kobj, KOBJ_ADD); + } else { + timeout = MAX_JIFFY_OFFSET; + } + + retval = fw_sysfs_wait_timeout(fw_priv, timeout); + if (retval < 0) { + mutex_lock(&fw_lock); + fw_load_abort(fw_sysfs); + mutex_unlock(&fw_lock); + } + + if (fw_state_is_aborted(fw_priv)) { + if (retval == -ERESTARTSYS) + retval = -EINTR; + else + retval = -EAGAIN; + } else if (fw_priv->is_paged_buf && !fw_priv->data) + retval = -ENOMEM; + + 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, + unsigned int opt_flags) +{ + struct fw_sysfs *fw_sysfs; + long timeout; + int ret; + + timeout = firmware_loading_timeout(); + if (opt_flags & FW_OPT_NOWAIT) { + timeout = usermodehelper_read_lock_wait(timeout); + if (!timeout) { + dev_dbg(device, "firmware: %s loading timed out\n", + name); + return -EBUSY; + } + } else { + ret = usermodehelper_read_trylock(); + if (WARN_ON(ret)) { + dev_err(device, "firmware: %s will not be loaded\n", + name); + return ret; + } + } + + fw_sysfs = fw_create_instance(firmware, name, device, opt_flags); + if (IS_ERR(fw_sysfs)) { + ret = PTR_ERR(fw_sysfs); + goto out_unlock; + } + + fw_sysfs->fw_priv = firmware->priv; + ret = _request_firmware_load(fw_sysfs, opt_flags, timeout); + + if (!ret) + ret = assign_fw(firmware, device, opt_flags); + +out_unlock: + usermodehelper_read_unlock(); + + return ret; +} + +static bool fw_force_sysfs_fallback(unsigned int opt_flags) +{ + if (fw_fallback_config.force_sysfs_fallback) + return true; + if (!(opt_flags & FW_OPT_USERHELPER)) + return false; + return true; +} + +static bool fw_run_sysfs_fallback(unsigned int opt_flags) +{ + if ((opt_flags & FW_OPT_NOFALLBACK)) + return false; + + return fw_force_sysfs_fallback(opt_flags); +} + +int fw_sysfs_fallback(struct firmware *fw, const char *name, + struct device *device, + unsigned int opt_flags, + int ret) +{ + if (!fw_run_sysfs_fallback(opt_flags)) + return ret; + + dev_warn(device, "Falling back to user helper\n"); + return fw_load_from_user_helper(fw, name, device, opt_flags); +} diff --git a/drivers/base/firmware_fallback.h b/drivers/base/firmware_fallback.h new file mode 100644 index 000000000000..550498c7fa4c --- /dev/null +++ b/drivers/base/firmware_fallback.h @@ -0,0 +1,61 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __FIRMWARE_FALLBACK_H +#define __FIRMWARE_FALLBACK_H + +#include <linux/firmware.h> +#include <linux/device.h> + +/** + * struct firmware_fallback_config - firmware fallback configuratioon settings + * + * Helps describe and fine tune the fallback mechanism. + * + * @force_sysfs_fallback: force the sysfs fallback mechanism to be used + * as if one had enabled CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y. + * @old_timeout: for internal use + * @loading_timeout: the timeout to wait for the fallback mechanism before + * giving up, in seconds. + */ +struct firmware_fallback_config { + const bool force_sysfs_fallback; + int old_timeout; + int loading_timeout; +}; + +#ifdef CONFIG_FW_LOADER_USER_HELPER +int fw_sysfs_fallback(struct firmware *fw, const char *name, + struct device *device, + unsigned int opt_flags, + int ret); +void kill_pending_fw_fallback_reqs(bool only_kill_custom); + +void fw_fallback_set_cache_timeout(void); +void fw_fallback_set_default_timeout(void); + +int register_sysfs_loader(void); +void unregister_sysfs_loader(void); +#else /* CONFIG_FW_LOADER_USER_HELPER */ +static inline int fw_sysfs_fallback(struct firmware *fw, const char *name, + struct device *device, + unsigned int opt_flags, + int ret) +{ + /* Keep carrying over the same error */ + return ret; +} + +static inline void kill_pending_fw_fallback_reqs(bool only_kill_custom) { } +static inline void fw_fallback_set_cache_timeout(void) { } +static inline void fw_fallback_set_default_timeout(void) { } + +static inline int register_sysfs_loader(void) +{ + return 0; +} + +static inline void unregister_sysfs_loader(void) +{ +} +#endif /* CONFIG_FW_LOADER_USER_HELPER */ + +#endif /* __FIRMWARE_FALLBACK_H */ diff --git a/drivers/base/firmware_fallback_table.c b/drivers/base/firmware_fallback_table.c new file mode 100644 index 000000000000..53cc4e492520 --- /dev/null +++ b/drivers/base/firmware_fallback_table.c @@ -0,0 +1,29 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/types.h> +#include <linux/kconfig.h> +#include <linux/list.h> +#include <linux/slab.h> +#include <linux/security.h> +#include <linux/highmem.h> +#include <linux/umh.h> +#include <linux/sysctl.h> + +#include "firmware_fallback.h" +#include "firmware_loader.h" + +/* + * firmware fallback configuration table + */ + +/* Module or buit-in */ +#ifdef CONFIG_FW_LOADER_USER_HELPER + +struct firmware_fallback_config fw_fallback_config = { + .force_sysfs_fallback = IS_ENABLED(CONFIG_FW_LOADER_USER_HELPER_FALLBACK), + .loading_timeout = 60, + .old_timeout = 60, +}; +EXPORT_SYMBOL_GPL(fw_fallback_config); + +#endif diff --git a/drivers/base/firmware_loader.c b/drivers/base/firmware_loader.c index 9757f9fff01e..21dd31ef08ae 100644 --- a/drivers/base/firmware_loader.c +++ b/drivers/base/firmware_loader.c @@ -37,36 +37,13 @@ #include <generated/utsrelease.h> #include "base.h" +#include "firmware_loader.h" +#include "firmware_fallback.h" MODULE_AUTHOR("Manuel Estrada Sainz"); MODULE_DESCRIPTION("Multi purpose firmware loading support"); MODULE_LICENSE("GPL"); -enum fw_status { - FW_STATUS_UNKNOWN, - FW_STATUS_LOADING, - FW_STATUS_DONE, - FW_STATUS_ABORTED, -}; - -/* - * Concurrent request_firmware() for the same firmware need to be - * serialized. struct fw_state is simple state machine which hold the - * state of the firmware loading. - */ -struct fw_state { - struct completion completion; - enum fw_status status; -}; - -/* firmware behavior options */ -#define FW_OPT_UEVENT (1U << 0) -#define FW_OPT_NOWAIT (1U << 1) -#define FW_OPT_USERHELPER (1U << 2) -#define FW_OPT_NO_WARN (1U << 3) -#define FW_OPT_NOCACHE (1U << 4) -#define FW_OPT_NOFALLBACK (1U << 5) - struct firmware_cache { /* firmware_buf instance will be added into the below list */ spinlock_t lock; @@ -89,25 +66,6 @@ struct firmware_cache { #endif }; -struct fw_priv { - struct kref ref; - struct list_head list; - struct firmware_cache *fwc; - struct fw_state fw_st; - void *data; - size_t size; - size_t allocated_size; -#ifdef CONFIG_FW_LOADER_USER_HELPER - bool is_paged_buf; - bool need_uevent; - struct page **pages; - int nr_pages; - int page_array_size; - struct list_head pending_list; -#endif - const char *fw_name; -}; - struct fw_cache_entry { struct list_head list; const char *name; @@ -128,7 +86,7 @@ static inline struct fw_priv *to_fw_priv(struct kref *ref) /* fw_lock could be moved to 'struct fw_sysfs' but since it is just * guarding for corner cases a global lock should be OK */ -static DEFINE_MUTEX(fw_lock); +DEFINE_MUTEX(fw_lock); static struct firmware_cache fw_cache; @@ -199,142 +157,11 @@ static void fw_state_init(struct fw_priv *fw_priv) fw_st->status = FW_STATUS_UNKNOWN; } -static int __fw_state_wait_common(struct fw_priv *fw_priv, long timeout) -{ - struct fw_state *fw_st = &fw_priv->fw_st; - long ret; - - ret = wait_for_completion_killable_timeout(&fw_st->completion, timeout); - if (ret != 0 && fw_st->status == FW_STATUS_ABORTED) - return -ENOENT; - if (!ret) - return -ETIMEDOUT; - - return ret < 0 ? ret : 0; -} - -static void __fw_state_set(struct fw_priv *fw_priv, - enum fw_status status) -{ - struct fw_state *fw_st = &fw_priv->fw_st; - - WRITE_ONCE(fw_st->status, status); - - if (status == FW_STATUS_DONE || status == FW_STATUS_ABORTED) - complete_all(&fw_st->completion); -} - -static inline void fw_state_start(struct fw_priv *fw_priv) -{ - __fw_state_set(fw_priv, FW_STATUS_LOADING); -} - -static inline void fw_state_done(struct fw_priv *fw_priv) -{ - __fw_state_set(fw_priv, FW_STATUS_DONE); -} - -static inline void fw_state_aborted(struct fw_priv *fw_priv) -{ - __fw_state_set(fw_priv, FW_STATUS_ABORTED); -} - static inline int fw_state_wait(struct fw_priv *fw_priv) { return __fw_state_wait_common(fw_priv, MAX_SCHEDULE_TIMEOUT); } -static bool __fw_state_check(struct fw_priv *fw_priv, - enum fw_status status) -{ - struct fw_state *fw_st = &fw_priv->fw_st; - - return fw_st->status == status; -} - -static inline bool fw_state_is_aborted(struct fw_priv *fw_priv) -{ - return __fw_state_check(fw_priv, FW_STATUS_ABORTED); -} - -#ifdef CONFIG_FW_LOADER_USER_HELPER - -/** - * struct firmware_fallback_config - firmware fallback configuratioon settings - * - * Helps describe and fine tune the fallback mechanism. - * - * @force_sysfs_fallback: force the sysfs fallback mechanism to be used - * as if one had enabled CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y. - * @old_timeout: for internal use - * @loading_timeout: the timeout to wait for the fallback mechanism before - * giving up, in seconds. - */ -struct firmware_fallback_config { - const bool force_sysfs_fallback; - int old_timeout; - int loading_timeout; -}; - -static struct firmware_fallback_config fw_fallback_config = { - .force_sysfs_fallback = IS_ENABLED(CONFIG_FW_LOADER_USER_HELPER_FALLBACK), - .loading_timeout = 60, - .old_timeout = 60, -}; - -/* These getters are vetted to use int properly */ -static inline int __firmware_loading_timeout(void) -{ - return fw_fallback_config.loading_timeout; -} - -/* These setters are vetted to use int properly */ -static void __fw_fallback_set_timeout(int timeout) -{ - fw_fallback_config.loading_timeout = timeout; -} - -static inline long firmware_loading_timeout(void) -{ - return __firmware_loading_timeout() > 0 ? - __firmware_loading_timeout() * HZ : MAX_JIFFY_OFFSET; -} - -/* - * 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. - */ -static void fw_fallback_set_cache_timeout(void) -{ - fw_fallback_config.old_timeout = __firmware_loading_timeout(); - __fw_fallback_set_timeout(10); -} - -/* Restores the timeout to the value last configured during normal operation */ -static void fw_fallback_set_default_timeout(void) -{ - __fw_fallback_set_timeout(fw_fallback_config.old_timeout); -} - -static inline bool fw_sysfs_done(struct fw_priv *fw_priv) -{ - return __fw_state_check(fw_priv, FW_STATUS_DONE); -} - -static inline bool fw_sysfs_loading(struct fw_priv *fw_priv) -{ - return __fw_state_check(fw_priv, FW_STATUS_LOADING); -} - -static inline int fw_sysfs_wait_timeout(struct fw_priv *fw_priv, long timeout) -{ - return __fw_state_wait_common(fw_priv, timeout); -} - -#endif /* CONFIG_FW_LOADER_USER_HELPER */ - static int fw_cache_piggyback_on_request(const char *name); static struct fw_priv *__allocate_fw_priv(const char *fw_name, @@ -600,8 +427,8 @@ static int fw_add_devm_name(struct device *dev, const char *name) } #endif -static int assign_fw(struct firmware *fw, struct device *device, - unsigned int opt_flags) +int assign_fw(struct firmware *fw, struct device *device, + unsigned int opt_flags) { struct fw_priv *fw_priv = fw->priv; @@ -639,626 +466,6 @@ static int assign_fw(struct firmware *fw, struct device *device, return 0; } -/* - * user-mode helper code - */ -#ifdef CONFIG_FW_LOADER_USER_HELPER -struct fw_sysfs { - bool nowait; - struct device dev; - struct fw_priv *fw_priv; - struct firmware *fw; -}; - -static struct fw_sysfs *to_fw_sysfs(struct device *dev) -{ - return container_of(dev, struct fw_sysfs, dev); -} - -static void __fw_load_abort(struct fw_priv *fw_priv) -{ - /* - * There is a small window in which user can write to 'loading' - * between loading done and disappearance of 'loading' - */ - if (fw_sysfs_done(fw_priv)) - return; - - list_del_init(&fw_priv->pending_list); - fw_state_aborted(fw_priv); -} - -static void fw_load_abort(struct fw_sysfs *fw_sysfs) -{ - struct fw_priv *fw_priv = fw_sysfs->fw_priv; - - __fw_load_abort(fw_priv); -} - -static LIST_HEAD(pending_fw_head); - -static void kill_pending_fw_fallback_reqs(bool only_kill_custom) -{ - struct fw_priv *fw_priv; - struct fw_priv *next; - - mutex_lock(&fw_lock); - list_for_each_entry_safe(fw_priv, next, &pending_fw_head, - pending_list) { - if (!fw_priv->need_uevent || !only_kill_custom) - __fw_load_abort(fw_priv); - } - mutex_unlock(&fw_lock); -} - -static ssize_t timeout_show(struct class *class, struct class_attribute *attr, - char *buf) -{ - return sprintf(buf, "%d\n", __firmware_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 timeout_store(struct class *class, struct class_attribute *attr, - const char *buf, size_t count) -{ - int tmp_loading_timeout = simple_strtol(buf, NULL, 10); - - if (tmp_loading_timeout < 0) - tmp_loading_timeout = 0; - - __fw_fallback_set_timeout(tmp_loading_timeout); - - return count; -} -static CLASS_ATTR_RW(timeout); - -static struct attribute *firmware_class_attrs[] = { - &class_attr_timeout.attr, - NULL, -}; -ATTRIBUTE_GROUPS(firmware_class); - -static void fw_dev_release(struct device *dev) -{ - struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev); - - kfree(fw_sysfs); -} - -static int do_firmware_uevent(struct fw_sysfs *fw_sysfs, struct kobj_uevent_env *env) -{ - if (add_uevent_var(env, "FIRMWARE=%s", fw_sysfs->fw_priv->fw_name)) - return -ENOMEM; - if (add_uevent_var(env, "TIMEOUT=%i", __firmware_loading_timeout())) - return -ENOMEM; - if (add_uevent_var(env, "ASYNC=%d", fw_sysfs->nowait)) - return -ENOMEM; - - return 0; -} - -static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env) -{ - struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev); - int err = 0; - - mutex_lock(&fw_lock); - if (fw_sysfs->fw_priv) - err = do_firmware_uevent(fw_sysfs, env); - mutex_unlock(&fw_lock); - return err; -} - -static struct class firmware_class = { - .name = "firmware", - .class_groups = firmware_class_groups, - .dev_uevent = firmware_uevent, - .dev_release = fw_dev_release, -}; - -static inline int register_sysfs_loader(void) -{ - return class_register(&firmware_class); -} - -static inline void unregister_sysfs_loader(void) -{ - class_unregister(&firmware_class); -} - -static ssize_t firmware_loading_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev); - int loading = 0; - - mutex_lock(&fw_lock); - if (fw_sysfs->fw_priv) - loading = fw_sysfs_loading(fw_sysfs->fw_priv); - 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 map_fw_priv_pages(struct fw_priv *fw_priv) -{ - if (!fw_priv->is_paged_buf) - return 0; - - vunmap(fw_priv->data); - fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0, - PAGE_KERNEL_RO); - if (!fw_priv->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 fw_sysfs *fw_sysfs = to_fw_sysfs(dev); - struct fw_priv *fw_priv; - ssize_t written = count; - int loading = simple_strtol(buf, NULL, 10); - int i; - - mutex_lock(&fw_lock); - fw_priv = fw_sysfs->fw_priv; - if (fw_state_is_aborted(fw_priv)) - goto out; - - switch (loading) { - case 1: - /* discarding any previous partial load */ - if (!fw_sysfs_done(fw_priv)) { - for (i = 0; i < fw_priv->nr_pages; i++) - __free_page(fw_priv->pages[i]); - vfree(fw_priv->pages); - fw_priv->pages = NULL; - fw_priv->page_array_size = 0; - fw_priv->nr_pages = 0; - fw_state_start(fw_priv); - } - break; - case 0: - if (fw_sysfs_loading(fw_priv)) { - int rc; - - /* - * 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. - * */ - rc = map_fw_priv_pages(fw_priv); - if (rc) - dev_err(dev, "%s: map pages failed\n", - __func__); - else - rc = security_kernel_post_read_file(NULL, - fw_priv->data, fw_priv->size, - READING_FIRMWARE); - - /* - * Same logic as fw_load_abort, only the DONE bit - * is ignored and we set ABORT only on failure. - */ - list_del_init(&fw_priv->pending_list); - if (rc) { - fw_state_aborted(fw_priv); - written = rc; - } else { - fw_state_done(fw_priv); - } - break; - } - /* fallthrough */ - default: - dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading); - /* fallthrough */ - case -1: - fw_load_abort(fw_sysfs); - break; - } -out: - mutex_unlock(&fw_lock); - return written; -} - -static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store); - -static void firmware_rw_data(struct fw_priv *fw_priv, char *buffer, - loff_t offset, size_t count, bool read) -{ - if (read) - memcpy(buffer, fw_priv->data + offset, count); - else - memcpy(fw_priv->data + offset, buffer, count); -} - -static void firmware_rw(struct fw_priv *fw_priv, char *buffer, - loff_t offset, size_t count, bool read) -{ - 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(fw_priv->pages[page_nr]); - - if (read) - memcpy(buffer, page_data + page_ofs, page_cnt); - else - memcpy(page_data + page_ofs, buffer, page_cnt); - - kunmap(fw_priv->pages[page_nr]); - buffer += page_cnt; - offset += page_cnt; - count -= page_cnt; - } -} - -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 fw_sysfs *fw_sysfs = to_fw_sysfs(dev); - struct fw_priv *fw_priv; - ssize_t ret_count; - - mutex_lock(&fw_lock); - fw_priv = fw_sysfs->fw_priv; - if (!fw_priv || fw_sysfs_done(fw_priv)) { - ret_count = -ENODEV; - goto out; - } - if (offset > fw_priv->size) { - ret_count = 0; - goto out; - } - if (count > fw_priv->size - offset) - count = fw_priv->size - offset; - - ret_count = count; - - if (fw_priv->data) - firmware_rw_data(fw_priv, buffer, offset, count, true); - else - firmware_rw(fw_priv, buffer, offset, count, true); - -out: - mutex_unlock(&fw_lock); - return ret_count; -} - -static int fw_realloc_pages(struct fw_sysfs *fw_sysfs, int min_size) -{ - struct fw_priv *fw_priv= fw_sysfs->fw_priv; - int pages_needed = PAGE_ALIGN(min_size) >> PAGE_SHIFT; - - /* If the array of pages is too small, grow it... */ - if (fw_priv->page_array_size < pages_needed) { - int new_array_size = max(pages_needed, - fw_priv->page_array_size * 2); - struct page **new_pages; - - new_pages = vmalloc(new_array_size * sizeof(void *)); - if (!new_pages) { - fw_load_abort(fw_sysfs); - return -ENOMEM; - } - memcpy(new_pages, fw_priv->pages, - fw_priv->page_array_size * sizeof(void *)); - memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) * - (new_array_size - fw_priv->page_array_size)); - vfree(fw_priv->pages); - fw_priv->pages = new_pages; - fw_priv->page_array_size = new_array_size; - } - - while (fw_priv->nr_pages < pages_needed) { - fw_priv->pages[fw_priv->nr_pages] = - alloc_page(GFP_KERNEL | __GFP_HIGHMEM); - - if (!fw_priv->pages[fw_priv->nr_pages]) { - fw_load_abort(fw_sysfs); - return -ENOMEM; - } - fw_priv->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 fw_sysfs *fw_sysfs = to_fw_sysfs(dev); - struct fw_priv *fw_priv; - ssize_t retval; - - if (!capable(CAP_SYS_RAWIO)) - return -EPERM; - - mutex_lock(&fw_lock); - fw_priv = fw_sysfs->fw_priv; - if (!fw_priv || fw_sysfs_done(fw_priv)) { - retval = -ENODEV; - goto out; - } - - if (fw_priv->data) { - if (offset + count > fw_priv->allocated_size) { - retval = -ENOMEM; - goto out; - } - firmware_rw_data(fw_priv, buffer, offset, count, false); - retval = count; - } else { - retval = fw_realloc_pages(fw_sysfs, offset + count); - if (retval) - goto out; - - retval = count; - firmware_rw(fw_priv, buffer, offset, count, false); - } - - fw_priv->size = max_t(size_t, offset + count, fw_priv->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 struct attribute *fw_dev_attrs[] = { - &dev_attr_loading.attr, - NULL -}; - -static struct bin_attribute *fw_dev_bin_attrs[] = { - &firmware_attr_data, - NULL -}; - -static const struct attribute_group fw_dev_attr_group = { - .attrs = fw_dev_attrs, - .bin_attrs = fw_dev_bin_attrs, -}; - -static const struct attribute_group *fw_dev_attr_groups[] = { - &fw_dev_attr_group, - NULL -}; - -static struct fw_sysfs * -fw_create_instance(struct firmware *firmware, const char *fw_name, - struct device *device, unsigned int opt_flags) -{ - struct fw_sysfs *fw_sysfs; - struct device *f_dev; - - fw_sysfs = kzalloc(sizeof(*fw_sysfs), GFP_KERNEL); - if (!fw_sysfs) { - fw_sysfs = ERR_PTR(-ENOMEM); - goto exit; - } - - fw_sysfs->nowait = !!(opt_flags & FW_OPT_NOWAIT); - fw_sysfs->fw = firmware; - f_dev = &fw_sysfs->dev; - - device_initialize(f_dev); - dev_set_name(f_dev, "%s", fw_name); - f_dev->parent = device; - f_dev->class = &firmware_class; - f_dev->groups = fw_dev_attr_groups; -exit: - return fw_sysfs; -} - -/* load a firmware via user helper */ -static int _request_firmware_load(struct fw_sysfs *fw_sysfs, - unsigned int opt_flags, long timeout) -{ - int retval = 0; - struct device *f_dev = &fw_sysfs->dev; - struct fw_priv *fw_priv = fw_sysfs->fw_priv; - - /* fall back on userspace loading */ - if (!fw_priv->data) - fw_priv->is_paged_buf = true; - - dev_set_uevent_suppress(f_dev, true); - - retval = device_add(f_dev); - if (retval) { - dev_err(f_dev, "%s: device_register failed\n", __func__); - goto err_put_dev; - } - - mutex_lock(&fw_lock); - list_add(&fw_priv->pending_list, &pending_fw_head); - mutex_unlock(&fw_lock); - - if (opt_flags & FW_OPT_UEVENT) { - fw_priv->need_uevent = true; - dev_set_uevent_suppress(f_dev, false); - dev_dbg(f_dev, "firmware: requesting %s\n", fw_priv->fw_name); - kobject_uevent(&fw_sysfs->dev.kobj, KOBJ_ADD); - } else { - timeout = MAX_JIFFY_OFFSET; - } - - retval = fw_sysfs_wait_timeout(fw_priv, timeout); - if (retval < 0) { - mutex_lock(&fw_lock); - fw_load_abort(fw_sysfs); - mutex_unlock(&fw_lock); - } - - if (fw_state_is_aborted(fw_priv)) { - if (retval == -ERESTARTSYS) - retval = -EINTR; - else - retval = -EAGAIN; - } else if (fw_priv->is_paged_buf && !fw_priv->data) - retval = -ENOMEM; - - 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, - unsigned int opt_flags) -{ - struct fw_sysfs *fw_sysfs; - long timeout; - int ret; - - timeout = firmware_loading_timeout(); - if (opt_flags & FW_OPT_NOWAIT) { - timeout = usermodehelper_read_lock_wait(timeout); - if (!timeout) { - dev_dbg(device, "firmware: %s loading timed out\n", - name); - return -EBUSY; - } - } else { - ret = usermodehelper_read_trylock(); - if (WARN_ON(ret)) { - dev_err(device, "firmware: %s will not be loaded\n", - name); - return ret; - } - } - - fw_sysfs = fw_create_instance(firmware, name, device, opt_flags); - if (IS_ERR(fw_sysfs)) { - ret = PTR_ERR(fw_sysfs); - goto out_unlock; - } - - fw_sysfs->fw_priv = firmware->priv; - ret = _request_firmware_load(fw_sysfs, opt_flags, timeout); - - if (!ret) - ret = assign_fw(firmware, device, opt_flags); - -out_unlock: - usermodehelper_read_unlock(); - - return ret; -} - -static bool fw_force_sysfs_fallback(unsigned int opt_flags) -{ - if (fw_fallback_config.force_sysfs_fallback) - return true; - if (!(opt_flags & FW_OPT_USERHELPER)) - return false; - return true; -} - -static bool fw_run_sysfs_fallback(unsigned int opt_flags) -{ - if ((opt_flags & FW_OPT_NOFALLBACK)) - return false; - - return fw_force_sysfs_fallback(opt_flags); -} - -static int fw_sysfs_fallback(struct firmware *fw, const char *name, - struct device *device, - unsigned int opt_flags, - int ret) -{ - if (!fw_run_sysfs_fallback(opt_flags)) - return ret; - - dev_warn(device, "Falling back to user helper\n"); - return fw_load_from_user_helper(fw, name, device, opt_flags); -} -#else /* CONFIG_FW_LOADER_USER_HELPER */ -static int fw_sysfs_fallback(struct firmware *fw, const char *name, - struct device *device, - unsigned int opt_flags, - int ret) -{ - /* Keep carrying over the same error */ - return ret; -} - -static inline void kill_pending_fw_fallback_reqs(bool only_kill_custom) { } -static inline void fw_fallback_set_cache_timeout(void) { } -static inline void fw_fallback_set_default_timeout(void) { } - -static inline int register_sysfs_loader(void) -{ - return 0; -} - -static inline void unregister_sysfs_loader(void) -{ -} - -#endif /* CONFIG_FW_LOADER_USER_HELPER */ - /* 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 diff --git a/drivers/base/firmware_loader.h b/drivers/base/firmware_loader.h new file mode 100644 index 000000000000..64acbb1a392c --- /dev/null +++ b/drivers/base/firmware_loader.h @@ -0,0 +1,115 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __FIRMWARE_LOADER_H +#define __FIRMWARE_LOADER_H + +#include <linux/firmware.h> +#include <linux/types.h> +#include <linux/kref.h> +#include <linux/list.h> +#include <linux/completion.h> + +#include <generated/utsrelease.h> + +/* firmware behavior options */ +#define FW_OPT_UEVENT (1U << 0) +#define FW_OPT_NOWAIT (1U << 1) +#define FW_OPT_USERHELPER (1U << 2) +#define FW_OPT_NO_WARN (1U << 3) +#define FW_OPT_NOCACHE (1U << 4) +#define FW_OPT_NOFALLBACK (1U << 5) + +enum fw_status { + FW_STATUS_UNKNOWN, + FW_STATUS_LOADING, + FW_STATUS_DONE, + FW_STATUS_ABORTED, +}; + +/* + * Concurrent request_firmware() for the same firmware need to be + * serialized. struct fw_state is simple state machine which hold the + * state of the firmware loading. + */ +struct fw_state { + struct completion completion; + enum fw_status status; +}; + +struct fw_priv { + struct kref ref; + struct list_head list; + struct firmware_cache *fwc; + struct fw_state fw_st; + void *data; + size_t size; + size_t allocated_size; +#ifdef CONFIG_FW_LOADER_USER_HELPER + bool is_paged_buf; + bool need_uevent; + struct page **pages; + int nr_pages; + int page_array_size; + struct list_head pending_list; +#endif + const char *fw_name; +}; + +extern struct mutex fw_lock; + +static inline bool __fw_state_check(struct fw_priv *fw_priv, + enum fw_status status) +{ + struct fw_state *fw_st = &fw_priv->fw_st; + + return fw_st->status == status; +} + +static inline int __fw_state_wait_common(struct fw_priv *fw_priv, long timeout) +{ + struct fw_state *fw_st = &fw_priv->fw_st; + long ret; + + ret = wait_for_completion_killable_timeout(&fw_st->completion, timeout); + if (ret != 0 && fw_st->status == FW_STATUS_ABORTED) + return -ENOENT; + if (!ret) + return -ETIMEDOUT; + + return ret < 0 ? ret : 0; +} + +static inline void __fw_state_set(struct fw_priv *fw_priv, + enum fw_status status) +{ + struct fw_state *fw_st = &fw_priv->fw_st; + + WRITE_ONCE(fw_st->status, status); + + if (status == FW_STATUS_DONE || status == FW_STATUS_ABORTED) + complete_all(&fw_st->completion); +} + +static inline void fw_state_aborted(struct fw_priv *fw_priv) +{ + __fw_state_set(fw_priv, FW_STATUS_ABORTED); +} + +static inline bool fw_state_is_aborted(struct fw_priv *fw_priv) +{ + return __fw_state_check(fw_priv, FW_STATUS_ABORTED); +} + +static inline void fw_state_start(struct fw_priv *fw_priv) +{ + __fw_state_set(fw_priv, FW_STATUS_LOADING); +} + +static inline void fw_state_done(struct fw_priv *fw_priv) +{ + __fw_state_set(fw_priv, FW_STATUS_DONE); +} + +int assign_fw(struct firmware *fw, struct device *device, + unsigned int opt_flags); + +#endif /* __FIRMWARE_LOADER_H */ |