diff --git a/drivers/base/firmware_loader/Kconfig b/drivers/base/firmware_loader/Kconfig index 08bb50451a96..d13e4383ea0c 100644 --- a/drivers/base/firmware_loader/Kconfig +++ b/drivers/base/firmware_loader/Kconfig @@ -29,6 +29,9 @@ if FW_LOADER config FW_LOADER_PAGED_BUF bool +config FW_LOADER_SYSFS + bool + config EXTRA_FIRMWARE string "Build named firmware blobs into the kernel binary" help @@ -72,6 +75,7 @@ config EXTRA_FIRMWARE_DIR config FW_LOADER_USER_HELPER bool "Enable the firmware sysfs fallback mechanism" + select FW_LOADER_SYSFS select FW_LOADER_PAGED_BUF help This option enables a sysfs loading facility to enable firmware diff --git a/drivers/base/firmware_loader/Makefile b/drivers/base/firmware_loader/Makefile index e87843408fe6..aab213f82288 100644 --- a/drivers/base/firmware_loader/Makefile +++ b/drivers/base/firmware_loader/Makefile @@ -6,5 +6,6 @@ obj-$(CONFIG_FW_LOADER) += firmware_class.o firmware_class-objs := main.o firmware_class-$(CONFIG_FW_LOADER_USER_HELPER) += fallback.o firmware_class-$(CONFIG_EFI_EMBEDDED_FIRMWARE) += fallback_platform.o +firmware_class-$(CONFIG_FW_LOADER_SYSFS) += sysfs.o obj-y += builtin/ diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c index 8063eb595719..bf68e3947814 100644 --- a/drivers/base/firmware_loader/fallback.c +++ b/drivers/base/firmware_loader/fallback.c @@ -3,12 +3,9 @@ #include #include #include -#include #include -#include #include #include -#include #include #include "fallback.h" @@ -18,22 +15,6 @@ * firmware fallback mechanism */ -MODULE_IMPORT_NS(FIRMWARE_LOADER_PRIVATE); - -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 @@ -63,37 +44,6 @@ 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/aborted and disappearance of 'loading' - */ - if (fw_state_is_aborted(fw_priv) || fw_state_is_done(fw_priv)) - return; - - 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) @@ -110,374 +60,6 @@ void kill_pending_fw_fallback_reqs(bool only_kill_custom) mutex_unlock(&fw_lock); } -static ssize_t timeout_show(struct class *class, struct class_attribute *attr, - char *buf) -{ - return sysfs_emit(buf, "%d\n", __firmware_loading_timeout()); -} - -/** - * 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) -{ - int ret = class_register(&firmware_class); - - if (ret != 0) - return ret; - return register_firmware_config_sysctl(); -} - -void unregister_sysfs_loader(void) -{ - unregister_firmware_config_sysctl(); - 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_state_is_loading(fw_sysfs->fw_priv); - mutex_unlock(&fw_lock); - - return sysfs_emit(buf, "%d\n", loading); -} - -/** - * 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); - - mutex_lock(&fw_lock); - fw_priv = fw_sysfs->fw_priv; - if (fw_state_is_aborted(fw_priv) || fw_state_is_done(fw_priv)) - goto out; - - switch (loading) { - case 1: - /* discarding any previous partial load */ - fw_free_paged_buf(fw_priv); - fw_state_start(fw_priv); - break; - case 0: - if (fw_state_is_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 = fw_map_paged_buf(fw_priv); - if (rc) - dev_err(dev, "%s: map pages failed\n", - __func__); - else - rc = security_kernel_post_load_data(fw_priv->data, - fw_priv->size, - LOADING_FIRMWARE, "blob"); - - /* - * Same logic as fw_load_abort, only the DONE bit - * is ignored and we set ABORT only on failure. - */ - 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_state_is_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) -{ - int err; - - err = fw_grow_paged_buf(fw_sysfs->fw_priv, - PAGE_ALIGN(min_size) >> PAGE_SHIFT); - if (err) - fw_load_abort(fw_sysfs); - return err; -} - -/** - * 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_state_is_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, u32 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; -} - /** * fw_load_sysfs_fallback() - load a firmware via the sysfs fallback mechanism * @fw_sysfs: firmware sysfs information for the firmware to load diff --git a/drivers/base/firmware_loader/fallback.h b/drivers/base/firmware_loader/fallback.h index 9f3055d3b4ca..144148595660 100644 --- a/drivers/base/firmware_loader/fallback.h +++ b/drivers/base/firmware_loader/fallback.h @@ -6,29 +6,7 @@ #include #include "firmware.h" - -/** - * struct firmware_fallback_config - firmware fallback configuration 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. - * Useful to help debug a CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y - * functionality on a kernel where that config entry has been disabled. - * @ignore_sysfs_fallback: force to disable the sysfs fallback mechanism. - * This emulates the behaviour as if we had set the kernel - * config CONFIG_FW_LOADER_USER_HELPER=n. - * @old_timeout: for internal use - * @loading_timeout: the timeout to wait for the fallback mechanism before - * giving up, in seconds. - */ -struct firmware_fallback_config { - unsigned int force_sysfs_fallback; - unsigned int ignore_sysfs_fallback; - int old_timeout; - int loading_timeout; -}; +#include "sysfs.h" #ifdef CONFIG_FW_LOADER_USER_HELPER int firmware_fallback_sysfs(struct firmware *fw, const char *name, @@ -40,19 +18,6 @@ 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); -#ifdef CONFIG_SYSCTL -extern int register_firmware_config_sysctl(void); -extern void unregister_firmware_config_sysctl(void); -#else -static inline int register_firmware_config_sysctl(void) -{ - return 0; -} -static inline void unregister_firmware_config_sysctl(void) { } -#endif /* CONFIG_SYSCTL */ - #else /* CONFIG_FW_LOADER_USER_HELPER */ static inline int firmware_fallback_sysfs(struct firmware *fw, const char *name, struct device *device, @@ -66,15 +31,6 @@ static inline int firmware_fallback_sysfs(struct firmware *fw, const char *name, 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 */ #ifdef CONFIG_EFI_EMBEDDED_FIRMWARE diff --git a/drivers/base/firmware_loader/sysfs.c b/drivers/base/firmware_loader/sysfs.c new file mode 100644 index 000000000000..1509cb6b6e60 --- /dev/null +++ b/drivers/base/firmware_loader/sysfs.c @@ -0,0 +1,401 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include +#include +#include + +#include "firmware.h" +#include "sysfs.h" + +/* + * sysfs support for firmware loader + */ + +void __fw_load_abort(struct fw_priv *fw_priv) +{ + /* + * There is a small window in which user can write to 'loading' + * between loading done/aborted and disappearance of 'loading' + */ + if (fw_state_is_aborted(fw_priv) || fw_state_is_done(fw_priv)) + return; + + fw_state_aborted(fw_priv); +} + +#ifdef CONFIG_FW_LOADER_USER_HELPER +static ssize_t timeout_show(struct class *class, struct class_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "%d\n", __firmware_loading_timeout()); +} + +/** + * 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 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; +} +#endif /* CONFIG_FW_LOADER_USER_HELPER */ + +static void fw_dev_release(struct device *dev) +{ + struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev); + + kfree(fw_sysfs); +} + +static struct class firmware_class = { + .name = "firmware", +#ifdef CONFIG_FW_LOADER_USER_HELPER + .class_groups = firmware_class_groups, + .dev_uevent = firmware_uevent, +#endif + .dev_release = fw_dev_release, +}; + +#ifdef CONFIG_FW_LOADER_USER_HELPER +int register_sysfs_loader(void) +{ + int ret = class_register(&firmware_class); + + if (ret != 0) + return ret; + return register_firmware_config_sysctl(); +} + +void unregister_sysfs_loader(void) +{ + unregister_firmware_config_sysctl(); + class_unregister(&firmware_class); +} +#endif + +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_state_is_loading(fw_sysfs->fw_priv); + mutex_unlock(&fw_lock); + + return sysfs_emit(buf, "%d\n", loading); +} + +/** + * 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); + + mutex_lock(&fw_lock); + fw_priv = fw_sysfs->fw_priv; + if (fw_state_is_aborted(fw_priv) || fw_state_is_done(fw_priv)) + goto out; + + switch (loading) { + case 1: + /* discarding any previous partial load */ + fw_free_paged_buf(fw_priv); + fw_state_start(fw_priv); + break; + case 0: + if (fw_state_is_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 = fw_map_paged_buf(fw_priv); + if (rc) + dev_err(dev, "%s: map pages failed\n", + __func__); + else + rc = security_kernel_post_load_data(fw_priv->data, + fw_priv->size, + LOADING_FIRMWARE, + "blob"); + + /* + * Same logic as fw_load_abort, only the DONE bit + * is ignored and we set ABORT only on failure. + */ + 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_state_is_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) +{ + int err; + + err = fw_grow_paged_buf(fw_sysfs->fw_priv, + PAGE_ALIGN(min_size) >> PAGE_SHIFT); + if (err) + fw_load_abort(fw_sysfs); + return err; +} + +/** + * 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_state_is_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 +}; + +struct fw_sysfs * +fw_create_instance(struct firmware *firmware, const char *fw_name, + struct device *device, u32 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; +} diff --git a/drivers/base/firmware_loader/sysfs.h b/drivers/base/firmware_loader/sysfs.h new file mode 100644 index 000000000000..b7b5c1766052 --- /dev/null +++ b/drivers/base/firmware_loader/sysfs.h @@ -0,0 +1,96 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __FIRMWARE_SYSFS_H +#define __FIRMWARE_SYSFS_H + +#include + +MODULE_IMPORT_NS(FIRMWARE_LOADER_PRIVATE); + +extern struct firmware_fallback_config fw_fallback_config; + +#ifdef CONFIG_FW_LOADER_USER_HELPER +/** + * struct firmware_fallback_config - firmware fallback configuration 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. + * Useful to help debug a CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y + * functionality on a kernel where that config entry has been disabled. + * @ignore_sysfs_fallback: force to disable the sysfs fallback mechanism. + * This emulates the behaviour as if we had set the kernel + * config CONFIG_FW_LOADER_USER_HELPER=n. + * @old_timeout: for internal use + * @loading_timeout: the timeout to wait for the fallback mechanism before + * giving up, in seconds. + */ +struct firmware_fallback_config { + unsigned int force_sysfs_fallback; + unsigned int ignore_sysfs_fallback; + int old_timeout; + int loading_timeout; +}; + +/* 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 inline void __fw_fallback_set_timeout(int timeout) +{ + fw_fallback_config.loading_timeout = timeout; +} + +int register_sysfs_loader(void); +void unregister_sysfs_loader(void); +#ifdef CONFIG_SYSCTL +int register_firmware_config_sysctl(void); +void unregister_firmware_config_sysctl(void); +#else +static inline int register_firmware_config_sysctl(void) +{ + return 0; +} + +static inline void unregister_firmware_config_sysctl(void) { } +#endif /* CONFIG_SYSCTL */ +#else /* CONFIG_FW_LOADER_USER_HELPER */ +static inline int register_sysfs_loader(void) +{ + return 0; +} + +static inline void unregister_sysfs_loader(void) +{ +} +#endif /* CONFIG_FW_LOADER_USER_HELPER */ + +struct fw_sysfs { + bool nowait; + struct device dev; + struct fw_priv *fw_priv; + struct firmware *fw; +}; + +static inline struct fw_sysfs *to_fw_sysfs(struct device *dev) +{ + return container_of(dev, struct fw_sysfs, dev); +} + +void __fw_load_abort(struct fw_priv *fw_priv); + +static inline void fw_load_abort(struct fw_sysfs *fw_sysfs) +{ + struct fw_priv *fw_priv = fw_sysfs->fw_priv; + + __fw_load_abort(fw_priv); +} + +struct fw_sysfs * +fw_create_instance(struct firmware *firmware, const char *fw_name, + struct device *device, u32 opt_flags); + +#endif /* __FIRMWARE_SYSFS_H */