diff options
Diffstat (limited to 'drivers/base/firmware_loader')
| -rw-r--r-- | drivers/base/firmware_loader/Kconfig | 234 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/Makefile | 12 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/builtin/.gitignore | 2 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/builtin/Makefile | 42 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/builtin/main.c | 106 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/fallback.c | 235 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/fallback.h | 45 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/fallback_platform.c | 45 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/fallback_table.c | 69 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/firmware.h | 197 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/main.c | 1654 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/sysfs.c | 419 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/sysfs.h | 118 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/sysfs_upload.c | 407 | ||||
| -rw-r--r-- | drivers/base/firmware_loader/sysfs_upload.h | 41 |
15 files changed, 3626 insertions, 0 deletions
diff --git a/drivers/base/firmware_loader/Kconfig b/drivers/base/firmware_loader/Kconfig new file mode 100644 index 000000000..5ca00e02f --- /dev/null +++ b/drivers/base/firmware_loader/Kconfig @@ -0,0 +1,234 @@ +# SPDX-License-Identifier: GPL-2.0 +menu "Firmware loader" + +config FW_LOADER + tristate "Firmware loading facility" if EXPERT + select CRYPTO_HASH if FW_LOADER_DEBUG + select CRYPTO_SHA256 if FW_LOADER_DEBUG + default y + help + This enables the firmware loading facility in the kernel. The kernel + will first look for built-in firmware, if it has any. Next, it will + look for the requested firmware in a series of filesystem paths: + + o firmware_class path module parameter or kernel boot param + o /lib/firmware/updates/UTS_RELEASE + o /lib/firmware/updates + o /lib/firmware/UTS_RELEASE + o /lib/firmware + + Enabling this feature only increases your kernel image by about + 828 bytes, enable this option unless you are certain you don't + need firmware. + + You typically want this built-in (=y) but you can also enable this + as a module, in which case the firmware_class module will be built. + You also want to be sure to enable this built-in if you are going to + enable built-in firmware (CONFIG_EXTRA_FIRMWARE). + +config FW_LOADER_DEBUG + bool "Log filenames and checksums for loaded firmware" + depends on CRYPTO = FW_LOADER || CRYPTO=y + depends on DYNAMIC_DEBUG + depends on FW_LOADER + default FW_LOADER + help + Select this option to use dynamic debug to log firmware filenames and + SHA256 checksums to the kernel log for each firmware file that is + loaded. + +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 + Device drivers which require firmware can typically deal with + having the kernel load firmware from the various supported + /lib/firmware/ paths. This option enables you to build into the + kernel firmware files. Built-in firmware searches are preceded + over firmware lookups using your filesystem over the supported + /lib/firmware paths documented on CONFIG_FW_LOADER. + + This may be useful for testing or if the firmware is required early on + in boot and cannot rely on the firmware being placed in an initrd or + initramfs. + + This option is a string and takes the (space-separated) names of the + firmware files -- the same names that appear in MODULE_FIRMWARE() + and request_firmware() in the source. These files should exist under + the directory specified by the EXTRA_FIRMWARE_DIR option, which is + /lib/firmware by default. + + For example, you might set CONFIG_EXTRA_FIRMWARE="usb8388.bin", copy + the usb8388.bin file into /lib/firmware, and build the kernel. Then + any request_firmware("usb8388.bin") will be satisfied internally + inside the kernel without ever looking at your filesystem at runtime. + + WARNING: If you include additional firmware files into your binary + kernel image that are not available under the terms of the GPL, + then it may be a violation of the GPL to distribute the resulting + image since it combines both GPL and non-GPL work. You should + consult a lawyer of your own before distributing such an image. + + NOTE: Compressed files are not supported in EXTRA_FIRMWARE. + +config EXTRA_FIRMWARE_DIR + string "Firmware blobs root directory" + depends on EXTRA_FIRMWARE != "" + default "/lib/firmware" + help + This option controls the directory in which the kernel build system + looks for the firmware files listed in the EXTRA_FIRMWARE option. + +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 + loading to the kernel through userspace as a fallback mechanism + if and only if the kernel's direct filesystem lookup for the + firmware failed using the different /lib/firmware/ paths, or the + path specified in the firmware_class path module parameter, or the + firmware_class path kernel boot parameter if the firmware_class is + built-in. For details on how to work with the sysfs fallback mechanism + refer to Documentation/driver-api/firmware/fallback-mechanisms.rst. + + The direct filesystem lookup for firmware is always used first now. + + If the kernel's direct filesystem lookup for firmware fails to find + the requested firmware a sysfs fallback loading facility is made + available and userspace is informed about this through uevents. + The uevent can be suppressed if the driver explicitly requested it, + this is known as the driver using the custom fallback mechanism. + If the custom fallback mechanism is used userspace must always + acknowledge failure to find firmware as the timeout for the fallback + mechanism is disabled, and failed requests will linger forever. + + This used to be the default firmware loading facility, and udev used + to listen for uvents to load firmware for the kernel. The firmware + loading facility functionality in udev has been removed, as such it + can no longer be relied upon as a fallback mechanism. Linux no longer + relies on or uses a fallback mechanism in userspace. If you need to + rely on one refer to the permissively licensed firmwared: + + https://github.com/teg/firmwared + + Since this was the default firmware loading facility at one point, + old userspace may exist which relies upon it, and as such this + mechanism can never be removed from the kernel. + + You should only enable this functionality if you are certain you + require a fallback mechanism and have a userspace mechanism ready to + load firmware in case it is not found. One main reason for this may + be if you have drivers which require firmware built-in and for + whatever reason cannot place the required firmware in initramfs. + Another reason kernels may have this feature enabled is to support a + driver which explicitly relies on this fallback mechanism. Only two + drivers need this today: + + o CONFIG_LEDS_LP55XX_COMMON + o CONFIG_DELL_RBU + + Outside of supporting the above drivers, another reason for needing + this may be that your firmware resides outside of the paths the kernel + looks for and cannot possibly be specified using the firmware_class + path module parameter or kernel firmware_class path boot parameter + if firmware_class is built-in. + + A modern use case may be to temporarily mount a custom partition + during provisioning which is only accessible to userspace, and then + to use it to look for and fetch the required firmware. Such type of + driver functionality may not even ever be desirable upstream by + vendors, and as such is only required to be supported as an interface + for provisioning. Since udev's firmware loading facility has been + removed you can use firmwared or a fork of it to customize how you + want to load firmware based on uevents issued. + + Enabling this option will increase your kernel image size by about + 13436 bytes. + + If you are unsure about this, say N here, unless you are Linux + distribution and need to support the above two drivers, or you are + certain you need to support some really custom firmware loading + facility in userspace. + +config FW_LOADER_USER_HELPER_FALLBACK + bool "Force the firmware sysfs fallback mechanism when possible" + depends on FW_LOADER_USER_HELPER + help + Enabling this option forces a sysfs userspace fallback mechanism + to be used for all firmware requests which explicitly do not disable a + a fallback mechanism. Firmware calls which do prohibit a fallback + mechanism is request_firmware_direct(). This option is kept for + backward compatibility purposes given this precise mechanism can also + be enabled by setting the proc sysctl value to true: + + /proc/sys/kernel/firmware_config/force_sysfs_fallback + + If you are unsure about this, say N here. + +config FW_LOADER_COMPRESS + bool "Enable compressed firmware support" + help + This option enables the support for loading compressed firmware + files. The caller of firmware API receives the decompressed file + content. The compressed file is loaded as a fallback, only after + loading the raw file failed at first. + + Compressed firmware support does not apply to firmware images + that are built into the kernel image (CONFIG_EXTRA_FIRMWARE). + +if FW_LOADER_COMPRESS +config FW_LOADER_COMPRESS_XZ + bool "Enable XZ-compressed firmware support" + select FW_LOADER_PAGED_BUF + select XZ_DEC + default y + help + This option adds the support for XZ-compressed files. + The files have to be compressed with either none or crc32 + integrity check type (pass "-C crc32" option to xz command). + +config FW_LOADER_COMPRESS_ZSTD + bool "Enable ZSTD-compressed firmware support" + select ZSTD_DECOMPRESS + help + This option adds the support for ZSTD-compressed files. + +endif # FW_LOADER_COMPRESS + +config FW_CACHE + bool "Enable firmware caching during suspend" + depends on PM_SLEEP + default y if PM_SLEEP + help + Because firmware caching generates uevent messages that are sent + over a netlink socket, it can prevent suspend on many platforms. + It is also not always useful, so on such platforms we have the + option. + + If unsure, say Y. + +config FW_UPLOAD + bool "Enable users to initiate firmware updates using sysfs" + select FW_LOADER_SYSFS + select FW_LOADER_PAGED_BUF + help + Enabling this option will allow device drivers to expose a persistent + sysfs interface that allows firmware updates to be initiated from + userspace. For example, FPGA based PCIe cards load firmware and FPGA + images from local FLASH when the card boots. The images in FLASH may + be updated with new images provided by the user. Enable this device + to support cards that rely on user-initiated updates for firmware files. + + If unsure, say N. + +endif # FW_LOADER +endmenu diff --git a/drivers/base/firmware_loader/Makefile b/drivers/base/firmware_loader/Makefile new file mode 100644 index 000000000..60d19f9e0 --- /dev/null +++ b/drivers/base/firmware_loader/Makefile @@ -0,0 +1,12 @@ +# SPDX-License-Identifier: GPL-2.0 +# Makefile for the Linux firmware loader + +obj-$(CONFIG_FW_LOADER_USER_HELPER) += fallback_table.o +obj-$(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-$(CONFIG_FW_LOADER_SYSFS) += sysfs.o +firmware_class-$(CONFIG_FW_UPLOAD) += sysfs_upload.o + +obj-y += builtin/ diff --git a/drivers/base/firmware_loader/builtin/.gitignore b/drivers/base/firmware_loader/builtin/.gitignore new file mode 100644 index 000000000..166f76b43 --- /dev/null +++ b/drivers/base/firmware_loader/builtin/.gitignore @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0 +*.gen.S diff --git a/drivers/base/firmware_loader/builtin/Makefile b/drivers/base/firmware_loader/builtin/Makefile new file mode 100644 index 000000000..6c067dedc --- /dev/null +++ b/drivers/base/firmware_loader/builtin/Makefile @@ -0,0 +1,42 @@ +# SPDX-License-Identifier: GPL-2.0 +obj-y += main.o + +# Create $(fwdir) from $(CONFIG_EXTRA_FIRMWARE_DIR) -- if it doesn't have a +# leading /, it's relative to $(srctree). +fwdir := $(CONFIG_EXTRA_FIRMWARE_DIR) +fwdir := $(addprefix $(srctree)/,$(filter-out /%,$(fwdir)))$(filter /%,$(fwdir)) + +firmware := $(addsuffix .gen.o, $(CONFIG_EXTRA_FIRMWARE)) +obj-y += $(firmware) + +FWNAME = $(patsubst $(obj)/%.gen.S,%,$@) +FWSTR = $(subst $(comma),_,$(subst /,_,$(subst .,_,$(subst -,_,$(FWNAME))))) +ASM_WORD = $(if $(CONFIG_64BIT),.quad,.long) +ASM_ALIGN = $(if $(CONFIG_64BIT),3,2) +PROGBITS = $(if $(CONFIG_ARM),%,@)progbits + +filechk_fwbin = \ + echo "/* Generated by $(src)/Makefile */" ;\ + echo " .section .rodata" ;\ + echo " .p2align 4" ;\ + echo "_fw_$(FWSTR)_bin:" ;\ + echo " .incbin \"$(fwdir)/$(FWNAME)\"" ;\ + echo "_fw_end:" ;\ + echo " .section .rodata.str,\"aMS\",$(PROGBITS),1" ;\ + echo " .p2align $(ASM_ALIGN)" ;\ + echo "_fw_$(FWSTR)_name:" ;\ + echo " .string \"$(FWNAME)\"" ;\ + echo " .section .builtin_fw,\"a\",$(PROGBITS)" ;\ + echo " .p2align $(ASM_ALIGN)" ;\ + echo " $(ASM_WORD) _fw_$(FWSTR)_name" ;\ + echo " $(ASM_WORD) _fw_$(FWSTR)_bin" ;\ + echo " $(ASM_WORD) _fw_end - _fw_$(FWSTR)_bin" + +$(obj)/%.gen.S: FORCE + $(call filechk,fwbin) + +# The .o files depend on the binaries directly; the .S files don't. +$(addprefix $(obj)/, $(firmware)): $(obj)/%.gen.o: $(fwdir)/% + +targets := $(patsubst $(obj)/%,%, \ + $(shell find $(obj) -name \*.gen.S 2>/dev/null)) diff --git a/drivers/base/firmware_loader/builtin/main.c b/drivers/base/firmware_loader/builtin/main.c new file mode 100644 index 000000000..a065c3150 --- /dev/null +++ b/drivers/base/firmware_loader/builtin/main.c @@ -0,0 +1,106 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Builtin firmware support */ + +#include <linux/firmware.h> +#include "../firmware.h" + +/* Only if FW_LOADER=y */ +#ifdef CONFIG_FW_LOADER + +struct builtin_fw { + char *name; + void *data; + unsigned long size; +}; + +extern struct builtin_fw __start_builtin_fw[]; +extern struct builtin_fw __end_builtin_fw[]; + +static bool fw_copy_to_prealloc_buf(struct firmware *fw, + void *buf, size_t size) +{ + if (!buf) + return true; + if (size < fw->size) + return false; + memcpy(buf, fw->data, fw->size); + return true; +} + +/** + * firmware_request_builtin() - load builtin firmware + * @fw: pointer to firmware struct + * @name: name of firmware file + * + * Some use cases in the kernel have a requirement so that no memory allocator + * is involved as these calls take place early in boot process. An example is + * the x86 CPU microcode loader. In these cases all the caller wants is to see + * if the firmware was built-in and if so use it right away. This can be used + * for such cases. + * + * This looks for the firmware in the built-in kernel. Only if the kernel was + * built-in with the firmware you are looking for will this return successfully. + * + * Callers of this API do not need to use release_firmware() as the pointer to + * the firmware is expected to be provided locally on the stack of the caller. + **/ +bool firmware_request_builtin(struct firmware *fw, const char *name) +{ + struct builtin_fw *b_fw; + + if (!fw) + return false; + + 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; +} +EXPORT_SYMBOL_NS_GPL(firmware_request_builtin, TEST_FIRMWARE); + +/** + * firmware_request_builtin_buf() - load builtin firmware into optional buffer + * @fw: pointer to firmware struct + * @name: name of firmware file + * @buf: If set this lets you use a pre-allocated buffer so that the built-in + * firmware into is copied into. This field can be NULL. It is used by + * callers such as request_firmware_into_buf() and + * request_partial_firmware_into_buf() + * @size: if buf was provided, the max size of the allocated buffer available. + * If the built-in firmware does not fit into the pre-allocated @buf this + * call will fail. + * + * This looks for the firmware in the built-in kernel. Only if the kernel was + * built-in with the firmware you are looking for will this call possibly + * succeed. If you passed a @buf the firmware will be copied into it *iff* the + * built-in firmware fits into the pre-allocated buffer size specified in + * @size. + * + * This caller is to be used internally by the firmware_loader only. + **/ +bool firmware_request_builtin_buf(struct firmware *fw, const char *name, + void *buf, size_t size) +{ + if (!firmware_request_builtin(fw, name)) + return false; + + return fw_copy_to_prealloc_buf(fw, buf, size); +} + +bool firmware_is_builtin(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; +} + +#endif diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c new file mode 100644 index 000000000..bf68e3947 --- /dev/null +++ b/drivers/base/firmware_loader/fallback.c @@ -0,0 +1,235 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/types.h> +#include <linux/kconfig.h> +#include <linux/list.h> +#include <linux/security.h> +#include <linux/umh.h> +#include <linux/sysctl.h> +#include <linux/module.h> + +#include "fallback.h" +#include "firmware.h" + +/* + * firmware fallback mechanism + */ + +/* + * 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 int fw_sysfs_wait_timeout(struct fw_priv *fw_priv, long timeout) +{ + return __fw_state_wait_common(fw_priv, timeout); +} + +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); +} + +/** + * fw_load_sysfs_fallback() - load a firmware via the sysfs fallback mechanism + * @fw_sysfs: firmware sysfs information for the firmware to load + * @timeout: timeout to wait for the load + * + * In charge of constructing a sysfs fallback interface for firmware loading. + **/ +static int fw_load_sysfs_fallback(struct fw_sysfs *fw_sysfs, 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); + if (fw_state_is_aborted(fw_priv)) { + mutex_unlock(&fw_lock); + retval = -EINTR; + goto out; + } + list_add(&fw_priv->pending_list, &pending_fw_head); + mutex_unlock(&fw_lock); + + if (fw_priv->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 && retval != -ENOENT) { + 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 if (fw_priv->is_paged_buf && !fw_priv->data) + retval = -ENOMEM; + +out: + 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, + u32 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 = fw_load_sysfs_fallback(fw_sysfs, timeout); + + if (!ret) + ret = assign_fw(firmware, device); + +out_unlock: + usermodehelper_read_unlock(); + + return ret; +} + +static bool fw_force_sysfs_fallback(u32 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(u32 opt_flags) +{ + int ret; + + if (fw_fallback_config.ignore_sysfs_fallback) { + pr_info_once("Ignoring firmware sysfs fallback due to sysctl knob\n"); + return false; + } + + if ((opt_flags & FW_OPT_NOFALLBACK_SYSFS)) + return false; + + /* Also permit LSMs and IMA to fail firmware sysfs fallback */ + ret = security_kernel_load_data(LOADING_FIRMWARE, true); + if (ret < 0) + return false; + + return fw_force_sysfs_fallback(opt_flags); +} + +/** + * firmware_fallback_sysfs() - use the fallback mechanism to find firmware + * @fw: pointer to firmware image + * @name: name of firmware file to look for + * @device: device for which firmware is being loaded + * @opt_flags: options to control firmware loading behaviour, as defined by + * &enum fw_opt + * @ret: return value from direct lookup which triggered the fallback mechanism + * + * This function is called if direct lookup for the firmware failed, it enables + * a fallback mechanism through userspace by exposing a sysfs loading + * interface. Userspace is in charge of loading the firmware through the sysfs + * loading interface. This sysfs fallback mechanism may be disabled completely + * on a system by setting the proc sysctl value ignore_sysfs_fallback to true. + * If this is false we check if the internal API caller set the + * @FW_OPT_NOFALLBACK_SYSFS flag, if so it would also disable the fallback + * mechanism. A system may want to enforce the sysfs fallback mechanism at all + * times, it can do this by setting ignore_sysfs_fallback to false and + * force_sysfs_fallback to true. + * Enabling force_sysfs_fallback is functionally equivalent to build a kernel + * with CONFIG_FW_LOADER_USER_HELPER_FALLBACK. + **/ +int firmware_fallback_sysfs(struct firmware *fw, const char *name, + struct device *device, + u32 opt_flags, + int ret) +{ + if (!fw_run_sysfs_fallback(opt_flags)) + return ret; + + if (!(opt_flags & FW_OPT_NO_WARN)) + dev_warn(device, "Falling back to sysfs fallback for: %s\n", + name); + else + dev_dbg(device, "Falling back to sysfs fallback for: %s\n", + name); + return fw_load_from_user_helper(fw, name, device, opt_flags); +} diff --git a/drivers/base/firmware_loader/fallback.h b/drivers/base/firmware_loader/fallback.h new file mode 100644 index 000000000..144148595 --- /dev/null +++ b/drivers/base/firmware_loader/fallback.h @@ -0,0 +1,45 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __FIRMWARE_FALLBACK_H +#define __FIRMWARE_FALLBACK_H + +#include <linux/firmware.h> +#include <linux/device.h> + +#include "firmware.h" +#include "sysfs.h" + +#ifdef CONFIG_FW_LOADER_USER_HELPER +int firmware_fallback_sysfs(struct firmware *fw, const char *name, + struct device *device, + u32 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); + +#else /* CONFIG_FW_LOADER_USER_HELPER */ +static inline int firmware_fallback_sysfs(struct firmware *fw, const char *name, + struct device *device, + u32 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) { } +#endif /* CONFIG_FW_LOADER_USER_HELPER */ + +#ifdef CONFIG_EFI_EMBEDDED_FIRMWARE +int firmware_fallback_platform(struct fw_priv *fw_priv); +#else +static inline int firmware_fallback_platform(struct fw_priv *fw_priv) +{ + return -ENOENT; +} +#endif + +#endif /* __FIRMWARE_FALLBACK_H */ diff --git a/drivers/base/firmware_loader/fallback_platform.c b/drivers/base/firmware_loader/fallback_platform.c new file mode 100644 index 000000000..00af99f0a --- /dev/null +++ b/drivers/base/firmware_loader/fallback_platform.c @@ -0,0 +1,45 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/efi_embedded_fw.h> +#include <linux/property.h> +#include <linux/security.h> +#include <linux/vmalloc.h> + +#include "fallback.h" +#include "firmware.h" + +int firmware_fallback_platform(struct fw_priv *fw_priv) +{ + const u8 *data; + size_t size; + int rc; + + if (!(fw_priv->opt_flags & FW_OPT_FALLBACK_PLATFORM)) + return -ENOENT; + + rc = security_kernel_load_data(LOADING_FIRMWARE, true); + if (rc) + return rc; + + rc = efi_get_embedded_fw(fw_priv->fw_name, &data, &size); + if (rc) + return rc; /* rc == -ENOENT when the fw was not found */ + + if (fw_priv->data && size > fw_priv->allocated_size) + return -ENOMEM; + + rc = security_kernel_post_load_data((u8 *)data, size, LOADING_FIRMWARE, + "platform"); + if (rc) + return rc; + + if (!fw_priv->data) + fw_priv->data = vmalloc(size); + if (!fw_priv->data) + return -ENOMEM; + + memcpy(fw_priv->data, data, size); + fw_priv->size = size; + fw_state_done(fw_priv); + return 0; +} diff --git a/drivers/base/firmware_loader/fallback_table.c b/drivers/base/firmware_loader/fallback_table.c new file mode 100644 index 000000000..e5ac098d0 --- /dev/null +++ b/drivers/base/firmware_loader/fallback_table.c @@ -0,0 +1,69 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/types.h> +#include <linux/kconfig.h> +#include <linux/list.h> +#include <linux/slab.h> +#include <linux/export.h> +#include <linux/security.h> +#include <linux/highmem.h> +#include <linux/umh.h> +#include <linux/sysctl.h> + +#include "fallback.h" +#include "firmware.h" + +/* + * firmware fallback configuration table + */ + +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_NS_GPL(fw_fallback_config, FIRMWARE_LOADER_PRIVATE); + +#ifdef CONFIG_SYSCTL +static struct ctl_table firmware_config_table[] = { + { + .procname = "force_sysfs_fallback", + .data = &fw_fallback_config.force_sysfs_fallback, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = proc_douintvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, + }, + { + .procname = "ignore_sysfs_fallback", + .data = &fw_fallback_config.ignore_sysfs_fallback, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = proc_douintvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, + }, + { } +}; + +static struct ctl_table_header *firmware_config_sysct_table_header; +int register_firmware_config_sysctl(void) +{ + firmware_config_sysct_table_header = + register_sysctl("kernel/firmware_config", + firmware_config_table); + if (!firmware_config_sysct_table_header) + return -ENOMEM; + return 0; +} +EXPORT_SYMBOL_NS_GPL(register_firmware_config_sysctl, FIRMWARE_LOADER_PRIVATE); + +void unregister_firmware_config_sysctl(void) +{ + unregister_sysctl_table(firmware_config_sysct_table_header); + firmware_config_sysct_table_header = NULL; +} +EXPORT_SYMBOL_NS_GPL(unregister_firmware_config_sysctl, FIRMWARE_LOADER_PRIVATE); + +#endif /* CONFIG_SYSCTL */ diff --git a/drivers/base/firmware_loader/firmware.h b/drivers/base/firmware_loader/firmware.h new file mode 100644 index 000000000..bf549d650 --- /dev/null +++ b/drivers/base/firmware_loader/firmware.h @@ -0,0 +1,197 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __FIRMWARE_LOADER_H +#define __FIRMWARE_LOADER_H + +#include <linux/bitops.h> +#include <linux/firmware.h> +#include <linux/types.h> +#include <linux/kref.h> +#include <linux/list.h> +#include <linux/completion.h> + +/** + * enum fw_opt - options to control firmware loading behaviour + * + * @FW_OPT_UEVENT: Enables the fallback mechanism to send a kobject uevent + * when the firmware is not found. Userspace is in charge to load the + * firmware using the sysfs loading facility. + * @FW_OPT_NOWAIT: Used to describe the firmware request is asynchronous. + * @FW_OPT_USERHELPER: Enable the fallback mechanism, in case the direct + * filesystem lookup fails at finding the firmware. For details refer to + * firmware_fallback_sysfs(). + * @FW_OPT_NO_WARN: Quiet, avoid printing warning messages. + * @FW_OPT_NOCACHE: Disables firmware caching. Firmware caching is used to + * cache the firmware upon suspend, so that upon resume races against the + * firmware file lookup on storage is avoided. Used for calls where the + * file may be too big, or where the driver takes charge of its own + * firmware caching mechanism. + * @FW_OPT_NOFALLBACK_SYSFS: Disable the sysfs fallback mechanism. Takes + * precedence over &FW_OPT_UEVENT and &FW_OPT_USERHELPER. + * @FW_OPT_FALLBACK_PLATFORM: Enable fallback to device fw copy embedded in + * the platform's main firmware. If both this fallback and the sysfs + * fallback are enabled, then this fallback will be tried first. + * @FW_OPT_PARTIAL: Allow partial read of firmware instead of needing to read + * entire file. + */ +enum fw_opt { + FW_OPT_UEVENT = BIT(0), + FW_OPT_NOWAIT = BIT(1), + FW_OPT_USERHELPER = BIT(2), + FW_OPT_NO_WARN = BIT(3), + FW_OPT_NOCACHE = BIT(4), + FW_OPT_NOFALLBACK_SYSFS = BIT(5), + FW_OPT_FALLBACK_PLATFORM = BIT(6), + FW_OPT_PARTIAL = BIT(7), +}; + +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; + size_t offset; + u32 opt_flags; +#ifdef CONFIG_FW_LOADER_PAGED_BUF + bool is_paged_buf; + struct page **pages; + int nr_pages; + int page_array_size; +#endif +#ifdef CONFIG_FW_LOADER_USER_HELPER + bool need_uevent; + struct list_head pending_list; +#endif + const char *fw_name; +}; + +extern struct mutex fw_lock; +extern struct firmware_cache fw_cache; + +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) { +#ifdef CONFIG_FW_LOADER_USER_HELPER + /* + * Doing this here ensures that the fw_priv is deleted from + * the pending list in all abort/done paths. + */ + list_del_init(&fw_priv->pending_list); +#endif + 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); +} + +static inline bool fw_state_is_done(struct fw_priv *fw_priv) +{ + return __fw_state_check(fw_priv, FW_STATUS_DONE); +} + +static inline bool fw_state_is_loading(struct fw_priv *fw_priv) +{ + return __fw_state_check(fw_priv, FW_STATUS_LOADING); +} + +int alloc_lookup_fw_priv(const char *fw_name, struct firmware_cache *fwc, + struct fw_priv **fw_priv, void *dbuf, size_t size, + size_t offset, u32 opt_flags); +int assign_fw(struct firmware *fw, struct device *device); +void free_fw_priv(struct fw_priv *fw_priv); +void fw_state_init(struct fw_priv *fw_priv); + +#ifdef CONFIG_FW_LOADER +bool firmware_is_builtin(const struct firmware *fw); +bool firmware_request_builtin_buf(struct firmware *fw, const char *name, + void *buf, size_t size); +#else /* module case */ +static inline bool firmware_is_builtin(const struct firmware *fw) +{ + return false; +} +static inline bool firmware_request_builtin_buf(struct firmware *fw, + const char *name, + void *buf, size_t size) +{ + return false; +} +#endif + +#ifdef CONFIG_FW_LOADER_PAGED_BUF +void fw_free_paged_buf(struct fw_priv *fw_priv); +int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed); +int fw_map_paged_buf(struct fw_priv *fw_priv); +bool fw_is_paged_buf(struct fw_priv *fw_priv); +#else +static inline void fw_free_paged_buf(struct fw_priv *fw_priv) {} +static inline int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed) { return -ENXIO; } +static inline int fw_map_paged_buf(struct fw_priv *fw_priv) { return -ENXIO; } +static inline bool fw_is_paged_buf(struct fw_priv *fw_priv) { return false; } +#endif + +#endif /* __FIRMWARE_LOADER_H */ diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c new file mode 100644 index 000000000..b58c42f1b --- /dev/null +++ b/drivers/base/firmware_loader/main.c @@ -0,0 +1,1654 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * main.c - Multi purpose firmware loading support + * + * Copyright (c) 2003 Manuel Estrada Sainz + * + * Please see Documentation/driver-api/firmware/ for more information. + * + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/capability.h> +#include <linux/device.h> +#include <linux/kernel_read_file.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/initrd.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/fs.h> +#include <linux/async.h> +#include <linux/pm.h> +#include <linux/suspend.h> +#include <linux/syscore_ops.h> +#include <linux/reboot.h> +#include <linux/security.h> +#include <linux/zstd.h> +#include <linux/xz.h> + +#include <generated/utsrelease.h> + +#include "../base.h" +#include "firmware.h" +#include "fallback.h" + +MODULE_AUTHOR("Manuel Estrada Sainz"); +MODULE_DESCRIPTION("Multi purpose firmware loading support"); +MODULE_LICENSE("GPL"); + +struct firmware_cache { + /* firmware_buf instance will be added into the below list */ + spinlock_t lock; + struct list_head head; + int state; + +#ifdef CONFIG_FW_CACHE + /* + * 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 fw_cache_entry { + struct list_head list; + const char *name; +}; + +struct fw_name_devm { + unsigned long magic; + const char *name; +}; + +static inline struct fw_priv *to_fw_priv(struct kref *ref) +{ + return container_of(ref, struct fw_priv, ref); +} + +#define FW_LOADER_NO_CACHE 0 +#define FW_LOADER_START_CACHE 1 + +/* fw_lock could be moved to 'struct fw_sysfs' but since it is just + * guarding for corner cases a global lock should be OK */ +DEFINE_MUTEX(fw_lock); + +struct firmware_cache fw_cache; + +void fw_state_init(struct fw_priv *fw_priv) +{ + struct fw_state *fw_st = &fw_priv->fw_st; + + init_completion(&fw_st->completion); + fw_st->status = FW_STATUS_UNKNOWN; +} + +static inline int fw_state_wait(struct fw_priv *fw_priv) +{ + return __fw_state_wait_common(fw_priv, MAX_SCHEDULE_TIMEOUT); +} + +static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv); + +static struct fw_priv *__allocate_fw_priv(const char *fw_name, + struct firmware_cache *fwc, + void *dbuf, + size_t size, + size_t offset, + u32 opt_flags) +{ + struct fw_priv *fw_priv; + + /* For a partial read, the buffer must be preallocated. */ + if ((opt_flags & FW_OPT_PARTIAL) && !dbuf) + return NULL; + + /* Only partial reads are allowed to use an offset. */ + if (offset != 0 && !(opt_flags & FW_OPT_PARTIAL)) + return NULL; + + fw_priv = kzalloc(sizeof(*fw_priv), GFP_ATOMIC); + if (!fw_priv) + return NULL; + + fw_priv->fw_name = kstrdup_const(fw_name, GFP_ATOMIC); + if (!fw_priv->fw_name) { + kfree(fw_priv); + return NULL; + } + + kref_init(&fw_priv->ref); + fw_priv->fwc = fwc; + fw_priv->data = dbuf; + fw_priv->allocated_size = size; + fw_priv->offset = offset; + fw_priv->opt_flags = opt_flags; + fw_state_init(fw_priv); +#ifdef CONFIG_FW_LOADER_USER_HELPER + INIT_LIST_HEAD(&fw_priv->pending_list); +#endif + + pr_debug("%s: fw-%s fw_priv=%p\n", __func__, fw_name, fw_priv); + + return fw_priv; +} + +static struct fw_priv *__lookup_fw_priv(const char *fw_name) +{ + struct fw_priv *tmp; + struct firmware_cache *fwc = &fw_cache; + + list_for_each_entry(tmp, &fwc->head, list) + if (!strcmp(tmp->fw_name, fw_name)) + return tmp; + return NULL; +} + +/* Returns 1 for batching firmware requests with the same name */ +int alloc_lookup_fw_priv(const char *fw_name, struct firmware_cache *fwc, + struct fw_priv **fw_priv, void *dbuf, size_t size, + size_t offset, u32 opt_flags) +{ + struct fw_priv *tmp; + + spin_lock(&fwc->lock); + /* + * Do not merge requests that are marked to be non-cached or + * are performing partial reads. + */ + if (!(opt_flags & (FW_OPT_NOCACHE | FW_OPT_PARTIAL))) { + tmp = __lookup_fw_priv(fw_name); + if (tmp) { + kref_get(&tmp->ref); + spin_unlock(&fwc->lock); + *fw_priv = tmp; + pr_debug("batched request - sharing the same struct fw_priv and lookup for multiple requests\n"); + return 1; + } + } + + tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size, offset, opt_flags); + if (tmp) { + INIT_LIST_HEAD(&tmp->list); + if (!(opt_flags & FW_OPT_NOCACHE)) + list_add(&tmp->list, &fwc->head); + } + spin_unlock(&fwc->lock); + + *fw_priv = tmp; + + return tmp ? 0 : -ENOMEM; +} + +static void __free_fw_priv(struct kref *ref) + __releases(&fwc->lock) +{ + struct fw_priv *fw_priv = to_fw_priv(ref); + struct firmware_cache *fwc = fw_priv->fwc; + + pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n", + __func__, fw_priv->fw_name, fw_priv, fw_priv->data, + (unsigned int)fw_priv->size); + + list_del(&fw_priv->list); + spin_unlock(&fwc->lock); + + if (fw_is_paged_buf(fw_priv)) + fw_free_paged_buf(fw_priv); + else if (!fw_priv->allocated_size) + vfree(fw_priv->data); + + kfree_const(fw_priv->fw_name); + kfree(fw_priv); +} + +void free_fw_priv(struct fw_priv *fw_priv) +{ + struct firmware_cache *fwc = fw_priv->fwc; + spin_lock(&fwc->lock); + if (!kref_put(&fw_priv->ref, __free_fw_priv)) + spin_unlock(&fwc->lock); +} + +#ifdef CONFIG_FW_LOADER_PAGED_BUF +bool fw_is_paged_buf(struct fw_priv *fw_priv) +{ + return fw_priv->is_paged_buf; +} + +void fw_free_paged_buf(struct fw_priv *fw_priv) +{ + int i; + + if (!fw_priv->pages) + return; + + vunmap(fw_priv->data); + + for (i = 0; i < fw_priv->nr_pages; i++) + __free_page(fw_priv->pages[i]); + kvfree(fw_priv->pages); + fw_priv->pages = NULL; + fw_priv->page_array_size = 0; + fw_priv->nr_pages = 0; + fw_priv->data = NULL; + fw_priv->size = 0; +} + +int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed) +{ + /* 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 = kvmalloc_array(new_array_size, sizeof(void *), + GFP_KERNEL); + if (!new_pages) + 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)); + kvfree(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]) + return -ENOMEM; + fw_priv->nr_pages++; + } + + return 0; +} + +int fw_map_paged_buf(struct fw_priv *fw_priv) +{ + /* one pages buffer should be mapped/unmapped only once */ + if (!fw_priv->pages) + 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; +} +#endif + +/* + * ZSTD-compressed firmware support + */ +#ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD +static int fw_decompress_zstd(struct device *dev, struct fw_priv *fw_priv, + size_t in_size, const void *in_buffer) +{ + size_t len, out_size, workspace_size; + void *workspace, *out_buf; + zstd_dctx *ctx; + int err; + + if (fw_priv->allocated_size) { + out_size = fw_priv->allocated_size; + out_buf = fw_priv->data; + } else { + zstd_frame_header params; + + if (zstd_get_frame_header(¶ms, in_buffer, in_size) || + params.frameContentSize == ZSTD_CONTENTSIZE_UNKNOWN) { + dev_dbg(dev, "%s: invalid zstd header\n", __func__); + return -EINVAL; + } + out_size = params.frameContentSize; + out_buf = vzalloc(out_size); + if (!out_buf) + return -ENOMEM; + } + + workspace_size = zstd_dctx_workspace_bound(); + workspace = kvzalloc(workspace_size, GFP_KERNEL); + if (!workspace) { + err = -ENOMEM; + goto error; + } + + ctx = zstd_init_dctx(workspace, workspace_size); + if (!ctx) { + dev_dbg(dev, "%s: failed to initialize context\n", __func__); + err = -EINVAL; + goto error; + } + + len = zstd_decompress_dctx(ctx, out_buf, out_size, in_buffer, in_size); + if (zstd_is_error(len)) { + dev_dbg(dev, "%s: failed to decompress: %d\n", __func__, + zstd_get_error_code(len)); + err = -EINVAL; + goto error; + } + + if (!fw_priv->allocated_size) + fw_priv->data = out_buf; + fw_priv->size = len; + err = 0; + + error: + kvfree(workspace); + if (err && !fw_priv->allocated_size) + vfree(out_buf); + return err; +} +#endif /* CONFIG_FW_LOADER_COMPRESS_ZSTD */ + +/* + * XZ-compressed firmware support + */ +#ifdef CONFIG_FW_LOADER_COMPRESS_XZ +/* show an error and return the standard error code */ +static int fw_decompress_xz_error(struct device *dev, enum xz_ret xz_ret) +{ + if (xz_ret != XZ_STREAM_END) { + dev_warn(dev, "xz decompression failed (xz_ret=%d)\n", xz_ret); + return xz_ret == XZ_MEM_ERROR ? -ENOMEM : -EINVAL; + } + return 0; +} + +/* single-shot decompression onto the pre-allocated buffer */ +static int fw_decompress_xz_single(struct device *dev, struct fw_priv *fw_priv, + size_t in_size, const void *in_buffer) +{ + struct xz_dec *xz_dec; + struct xz_buf xz_buf; + enum xz_ret xz_ret; + + xz_dec = xz_dec_init(XZ_SINGLE, (u32)-1); + if (!xz_dec) + return -ENOMEM; + + xz_buf.in_size = in_size; + xz_buf.in = in_buffer; + xz_buf.in_pos = 0; + xz_buf.out_size = fw_priv->allocated_size; + xz_buf.out = fw_priv->data; + xz_buf.out_pos = 0; + + xz_ret = xz_dec_run(xz_dec, &xz_buf); + xz_dec_end(xz_dec); + + fw_priv->size = xz_buf.out_pos; + return fw_decompress_xz_error(dev, xz_ret); +} + +/* decompression on paged buffer and map it */ +static int fw_decompress_xz_pages(struct device *dev, struct fw_priv *fw_priv, + size_t in_size, const void *in_buffer) +{ + struct xz_dec *xz_dec; + struct xz_buf xz_buf; + enum xz_ret xz_ret; + struct page *page; + int err = 0; + + xz_dec = xz_dec_init(XZ_DYNALLOC, (u32)-1); + if (!xz_dec) + return -ENOMEM; + + xz_buf.in_size = in_size; + xz_buf.in = in_buffer; + xz_buf.in_pos = 0; + + fw_priv->is_paged_buf = true; + fw_priv->size = 0; + do { + if (fw_grow_paged_buf(fw_priv, fw_priv->nr_pages + 1)) { + err = -ENOMEM; + goto out; + } + + /* decompress onto the new allocated page */ + page = fw_priv->pages[fw_priv->nr_pages - 1]; + xz_buf.out = kmap_local_page(page); + xz_buf.out_pos = 0; + xz_buf.out_size = PAGE_SIZE; + xz_ret = xz_dec_run(xz_dec, &xz_buf); + kunmap_local(xz_buf.out); + fw_priv->size += xz_buf.out_pos; + /* partial decompression means either end or error */ + if (xz_buf.out_pos != PAGE_SIZE) + break; + } while (xz_ret == XZ_OK); + + err = fw_decompress_xz_error(dev, xz_ret); + if (!err) + err = fw_map_paged_buf(fw_priv); + + out: + xz_dec_end(xz_dec); + return err; +} + +static int fw_decompress_xz(struct device *dev, struct fw_priv *fw_priv, + size_t in_size, const void *in_buffer) +{ + /* if the buffer is pre-allocated, we can perform in single-shot mode */ + if (fw_priv->data) + return fw_decompress_xz_single(dev, fw_priv, in_size, in_buffer); + else + return fw_decompress_xz_pages(dev, fw_priv, in_size, in_buffer); +} +#endif /* CONFIG_FW_LOADER_COMPRESS_XZ */ + +/* 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"); + +static int +fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, + const char *suffix, + int (*decompress)(struct device *dev, + struct fw_priv *fw_priv, + size_t in_size, + const void *in_buffer)) +{ + size_t size; + int i, len, maxlen = 0; + int rc = -ENOENT; + char *path, *nt = NULL; + size_t msize = INT_MAX; + void *buffer = NULL; + + /* Already populated data member means we're loading into a buffer */ + if (!decompress && fw_priv->data) { + buffer = fw_priv->data; + msize = fw_priv->allocated_size; + } + + path = __getname(); + if (!path) + return -ENOMEM; + + wait_for_initramfs(); + for (i = 0; i < ARRAY_SIZE(fw_path); i++) { + size_t file_size = 0; + size_t *file_size_ptr = NULL; + + /* skip the unset customized path */ + if (!fw_path[i][0]) + continue; + + /* strip off \n from customized path */ + maxlen = strlen(fw_path[i]); + if (i == 0) { + nt = strchr(fw_path[i], '\n'); + if (nt) + maxlen = nt - fw_path[i]; + } + + len = snprintf(path, PATH_MAX, "%.*s/%s%s", + maxlen, fw_path[i], + fw_priv->fw_name, suffix); + if (len >= PATH_MAX) { + rc = -ENAMETOOLONG; + break; + } + + fw_priv->size = 0; + + /* + * The total file size is only examined when doing a partial + * read; the "full read" case needs to fail if the whole + * firmware was not completely loaded. + */ + if ((fw_priv->opt_flags & FW_OPT_PARTIAL) && buffer) + file_size_ptr = &file_size; + + /* load firmware files from the mount namespace of init */ + rc = kernel_read_file_from_path_initns(path, fw_priv->offset, + &buffer, msize, + file_size_ptr, + READING_FIRMWARE); + if (rc < 0) { + if (rc != -ENOENT) + dev_warn(device, "loading %s failed with error %d\n", + path, rc); + else + dev_dbg(device, "loading %s failed for no such file or directory.\n", + path); + continue; + } + size = rc; + rc = 0; + + dev_dbg(device, "Loading firmware from %s\n", path); + if (decompress) { + dev_dbg(device, "f/w decompressing %s\n", + fw_priv->fw_name); + rc = decompress(device, fw_priv, size, buffer); + /* discard the superfluous original content */ + vfree(buffer); + buffer = NULL; + if (rc) { + fw_free_paged_buf(fw_priv); + continue; + } + } else { + dev_dbg(device, "direct-loading %s\n", + fw_priv->fw_name); + if (!fw_priv->data) + fw_priv->data = buffer; + fw_priv->size = size; + } + fw_state_done(fw_priv); + break; + } + __putname(path); + + return rc; +} + +/* firmware holds the ownership of pages */ +static void firmware_free_data(const struct firmware *fw) +{ + /* Loaded directly? */ + if (!fw->priv) { + vfree(fw->data); + return; + } + free_fw_priv(fw->priv); +} + +/* store the pages buffer info firmware from buf */ +static void fw_set_page_data(struct fw_priv *fw_priv, struct firmware *fw) +{ + fw->priv = fw_priv; + fw->size = fw_priv->size; + fw->data = fw_priv->data; + + pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n", + __func__, fw_priv->fw_name, fw_priv, fw_priv->data, + (unsigned int)fw_priv->size); +} + +#ifdef CONFIG_FW_CACHE +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); + kfree_const(fwn->name); +} + +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; +} + +static bool fw_cache_is_setup(struct device *dev, const char *name) +{ + struct fw_name_devm *fwn; + + fwn = fw_find_devm_name(dev, name); + if (fwn) + return true; + + return false; +} + +/* add firmware name into devres list */ +static int fw_add_devm_name(struct device *dev, const char *name) +{ + struct fw_name_devm *fwn; + + if (fw_cache_is_setup(dev, name)) + return 0; + + fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm), + GFP_KERNEL); + if (!fwn) + return -ENOMEM; + fwn->name = kstrdup_const(name, GFP_KERNEL); + if (!fwn->name) { + devres_free(fwn); + return -ENOMEM; + } + + fwn->magic = (unsigned long)&fw_cache; + devres_add(dev, fwn); + + return 0; +} +#else +static bool fw_cache_is_setup(struct device *dev, const char *name) +{ + return false; +} + +static int fw_add_devm_name(struct device *dev, const char *name) +{ + return 0; +} +#endif + +int assign_fw(struct firmware *fw, struct device *device) +{ + struct fw_priv *fw_priv = fw->priv; + int ret; + + mutex_lock(&fw_lock); + if (!fw_priv->size || fw_state_is_aborted(fw_priv)) { + 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. + */ + /* don't cache firmware handled without uevent */ + if (device && (fw_priv->opt_flags & FW_OPT_UEVENT) && + !(fw_priv->opt_flags & FW_OPT_NOCACHE)) { + ret = fw_add_devm_name(device, fw_priv->fw_name); + if (ret) { + mutex_unlock(&fw_lock); + return ret; + } + } + + /* + * After caching firmware image is started, let it piggyback + * on request firmware. + */ + if (!(fw_priv->opt_flags & FW_OPT_NOCACHE) && + fw_priv->fwc->state == FW_LOADER_START_CACHE) + fw_cache_piggyback_on_request(fw_priv); + + /* pass the pages buffer to driver at the last minute */ + fw_set_page_data(fw_priv, fw); + mutex_unlock(&fw_lock); + return 0; +} + +/* 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, void *dbuf, size_t size, + size_t offset, u32 opt_flags) +{ + struct firmware *firmware; + struct fw_priv *fw_priv; + 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 (firmware_request_builtin_buf(firmware, name, dbuf, size)) { + dev_dbg(device, "using built-in %s\n", name); + return 0; /* assigned */ + } + + ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size, + offset, opt_flags); + + /* + * bind with 'priv' now to avoid warning in failure path + * of requesting firmware. + */ + firmware->priv = fw_priv; + + if (ret > 0) { + ret = fw_state_wait(fw_priv); + if (!ret) { + fw_set_page_data(fw_priv, firmware); + return 0; /* assigned */ + } + } + + if (ret < 0) + return ret; + return 1; /* need to load */ +} + +/* + * Batched requests need only one wake, we need to do this step last due to the + * fallback mechanism. The buf is protected with kref_get(), and it won't be + * released until the last user calls release_firmware(). + * + * Failed batched requests are possible as well, in such cases we just share + * the struct fw_priv and won't release it until all requests are woken + * and have gone through this same path. + */ +static void fw_abort_batch_reqs(struct firmware *fw) +{ + struct fw_priv *fw_priv; + + /* Loaded directly? */ + if (!fw || !fw->priv) + return; + + fw_priv = fw->priv; + mutex_lock(&fw_lock); + if (!fw_state_is_aborted(fw_priv)) + fw_state_aborted(fw_priv); + mutex_unlock(&fw_lock); +} + +#if defined(CONFIG_FW_LOADER_DEBUG) +#include <crypto/hash.h> +#include <crypto/sha2.h> + +static void fw_log_firmware_info(const struct firmware *fw, const char *name, struct device *device) +{ + struct shash_desc *shash; + struct crypto_shash *alg; + u8 *sha256buf; + char *outbuf; + + alg = crypto_alloc_shash("sha256", 0, 0); + if (IS_ERR(alg)) + return; + + sha256buf = kmalloc(SHA256_DIGEST_SIZE, GFP_KERNEL); + outbuf = kmalloc(SHA256_BLOCK_SIZE + 1, GFP_KERNEL); + shash = kmalloc(sizeof(*shash) + crypto_shash_descsize(alg), GFP_KERNEL); + if (!sha256buf || !outbuf || !shash) + goto out_free; + + shash->tfm = alg; + + if (crypto_shash_digest(shash, fw->data, fw->size, sha256buf) < 0) + goto out_shash; + + for (int i = 0; i < SHA256_DIGEST_SIZE; i++) + sprintf(&outbuf[i * 2], "%02x", sha256buf[i]); + outbuf[SHA256_BLOCK_SIZE] = 0; + dev_dbg(device, "Loaded FW: %s, sha256: %s\n", name, outbuf); + +out_shash: + crypto_free_shash(alg); +out_free: + kfree(shash); + kfree(outbuf); + kfree(sha256buf); +} +#else +static void fw_log_firmware_info(const struct firmware *fw, const char *name, + struct device *device) +{} +#endif + +/* called from request_firmware() and request_firmware_work_func() */ +static int +_request_firmware(const struct firmware **firmware_p, const char *name, + struct device *device, void *buf, size_t size, + size_t offset, u32 opt_flags) +{ + struct firmware *fw = NULL; + struct cred *kern_cred = NULL; + const struct cred *old_cred; + bool nondirect = false; + int ret; + + if (!firmware_p) + return -EINVAL; + + if (!name || name[0] == '\0') { + ret = -EINVAL; + goto out; + } + + ret = _request_firmware_prepare(&fw, name, device, buf, size, + offset, opt_flags); + if (ret <= 0) /* error or already assigned */ + goto out; + + /* + * We are about to try to access the firmware file. Because we may have been + * called by a driver when serving an unrelated request from userland, we use + * the kernel credentials to read the file. + */ + kern_cred = prepare_kernel_cred(&init_task); + if (!kern_cred) { + ret = -ENOMEM; + goto out; + } + old_cred = override_creds(kern_cred); + + ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL); + + /* Only full reads can support decompression, platform, and sysfs. */ + if (!(opt_flags & FW_OPT_PARTIAL)) + nondirect = true; + +#ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD + if (ret == -ENOENT && nondirect) + ret = fw_get_filesystem_firmware(device, fw->priv, ".zst", + fw_decompress_zstd); +#endif +#ifdef CONFIG_FW_LOADER_COMPRESS_XZ + if (ret == -ENOENT && nondirect) + ret = fw_get_filesystem_firmware(device, fw->priv, ".xz", + fw_decompress_xz); +#endif + if (ret == -ENOENT && nondirect) + ret = firmware_fallback_platform(fw->priv); + + if (ret) { + if (!(opt_flags & FW_OPT_NO_WARN)) + dev_warn(device, + "Direct firmware load for %s failed with error %d\n", + name, ret); + if (nondirect) + ret = firmware_fallback_sysfs(fw, name, device, + opt_flags, ret); + } else + ret = assign_fw(fw, device); + + revert_creds(old_cred); + put_cred(kern_cred); + +out: + if (ret < 0) { + fw_abort_batch_reqs(fw); + release_firmware(fw); + fw = NULL; + } else { + fw_log_firmware_info(fw, name, device); + } + + *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) +{ + int ret; + + /* Need to pin this module until return */ + __module_get(THIS_MODULE); + ret = _request_firmware(firmware_p, name, device, NULL, 0, 0, + FW_OPT_UEVENT); + module_put(THIS_MODULE); + return ret; +} +EXPORT_SYMBOL(request_firmware); + +/** + * firmware_request_nowarn() - request for an optional fw module + * @firmware: pointer to firmware image + * @name: name of firmware file + * @device: device for which firmware is being loaded + * + * This function is similar in behaviour to request_firmware(), except it + * doesn't produce warning messages when the file is not found. The sysfs + * fallback mechanism is enabled if direct filesystem lookup fails. However, + * failures to find the firmware file with it are still suppressed. It is + * therefore up to the driver to check for the return value of this call and to + * decide when to inform the users of errors. + **/ +int firmware_request_nowarn(const struct firmware **firmware, const char *name, + struct device *device) +{ + int ret; + + /* Need to pin this module until return */ + __module_get(THIS_MODULE); + ret = _request_firmware(firmware, name, device, NULL, 0, 0, + FW_OPT_UEVENT | FW_OPT_NO_WARN); + module_put(THIS_MODULE); + return ret; +} +EXPORT_SYMBOL_GPL(firmware_request_nowarn); + +/** + * request_firmware_direct() - load firmware directly without usermode helper + * @firmware_p: pointer to firmware image + * @name: name of firmware file + * @device: device for which firmware is being loaded + * + * This function works pretty much like request_firmware(), but this doesn't + * fall back to usermode helper even if the firmware couldn't be loaded + * directly from fs. Hence it's useful for loading optional firmwares, which + * aren't always present, without extra long timeouts of udev. + **/ +int request_firmware_direct(const struct firmware **firmware_p, + const char *name, struct device *device) +{ + int ret; + + __module_get(THIS_MODULE); + ret = _request_firmware(firmware_p, name, device, NULL, 0, 0, + FW_OPT_UEVENT | FW_OPT_NO_WARN | + FW_OPT_NOFALLBACK_SYSFS); + module_put(THIS_MODULE); + return ret; +} +EXPORT_SYMBOL_GPL(request_firmware_direct); + +/** + * firmware_request_platform() - request firmware with platform-fw fallback + * @firmware: pointer to firmware image + * @name: name of firmware file + * @device: device for which firmware is being loaded + * + * This function is similar in behaviour to request_firmware, except that if + * direct filesystem lookup fails, it will fallback to looking for a copy of the + * requested firmware embedded in the platform's main (e.g. UEFI) firmware. + **/ +int firmware_request_platform(const struct firmware **firmware, + const char *name, struct device *device) +{ + int ret; + + /* Need to pin this module until return */ + __module_get(THIS_MODULE); + ret = _request_firmware(firmware, name, device, NULL, 0, 0, + FW_OPT_UEVENT | FW_OPT_FALLBACK_PLATFORM); + module_put(THIS_MODULE); + return ret; +} +EXPORT_SYMBOL_GPL(firmware_request_platform); + +/** + * firmware_request_cache() - cache firmware for suspend so resume can use it + * @name: name of firmware file + * @device: device for which firmware should be cached for + * + * There are some devices with an optimization that enables the device to not + * require loading firmware on system reboot. This optimization may still + * require the firmware present on resume from suspend. This routine can be + * used to ensure the firmware is present on resume from suspend in these + * situations. This helper is not compatible with drivers which use + * request_firmware_into_buf() or request_firmware_nowait() with no uevent set. + **/ +int firmware_request_cache(struct device *device, const char *name) +{ + int ret; + + mutex_lock(&fw_lock); + ret = fw_add_devm_name(device, name); + mutex_unlock(&fw_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(firmware_request_cache); + +/** + * request_firmware_into_buf() - load firmware into a previously allocated buffer + * @firmware_p: pointer to firmware image + * @name: name of firmware file + * @device: device for which firmware is being loaded and DMA region allocated + * @buf: address of buffer to load firmware into + * @size: size of buffer + * + * This function works pretty much like request_firmware(), but it doesn't + * allocate a buffer to hold the firmware data. Instead, the firmware + * is loaded directly into the buffer pointed to by @buf and the @firmware_p + * data member is pointed at @buf. + * + * This function doesn't cache firmware either. + */ +int +request_firmware_into_buf(const struct firmware **firmware_p, const char *name, + struct device *device, void *buf, size_t size) +{ + int ret; + + if (fw_cache_is_setup(device, name)) + return -EOPNOTSUPP; + + __module_get(THIS_MODULE); + ret = _request_firmware(firmware_p, name, device, buf, size, 0, + FW_OPT_UEVENT | FW_OPT_NOCACHE); + module_put(THIS_MODULE); + return ret; +} +EXPORT_SYMBOL(request_firmware_into_buf); + +/** + * request_partial_firmware_into_buf() - load partial firmware into a previously allocated buffer + * @firmware_p: pointer to firmware image + * @name: name of firmware file + * @device: device for which firmware is being loaded and DMA region allocated + * @buf: address of buffer to load firmware into + * @size: size of buffer + * @offset: offset into file to read + * + * This function works pretty much like request_firmware_into_buf except + * it allows a partial read of the file. + */ +int +request_partial_firmware_into_buf(const struct firmware **firmware_p, + const char *name, struct device *device, + void *buf, size_t size, size_t offset) +{ + int ret; + + if (fw_cache_is_setup(device, name)) + return -EOPNOTSUPP; + + __module_get(THIS_MODULE); + ret = _request_firmware(firmware_p, name, device, buf, size, offset, + FW_OPT_UEVENT | FW_OPT_NOCACHE | + FW_OPT_PARTIAL); + module_put(THIS_MODULE); + return ret; +} +EXPORT_SYMBOL(request_partial_firmware_into_buf); + +/** + * 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 (!firmware_is_builtin(fw)) + firmware_free_data(fw); + kfree(fw); + } +} +EXPORT_SYMBOL(release_firmware); + +/* 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); + u32 opt_flags; +}; + +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, NULL, 0, 0, + fw_work->opt_flags); + fw_work->cont(fw, fw_work->context); + put_device(fw_work->device); /* taken in request_firmware_nowait() */ + + module_put(fw_work->module); + kfree_const(fw_work->name); + 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 = kstrdup_const(name, gfp); + if (!fw_work->name) { + kfree(fw_work); + return -ENOMEM; + } + fw_work->device = device; + fw_work->context = context; + fw_work->cont = cont; + fw_work->opt_flags = FW_OPT_NOWAIT | + (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER); + + if (!uevent && fw_cache_is_setup(device, name)) { + kfree_const(fw_work->name); + kfree(fw_work); + return -EOPNOTSUPP; + } + + if (!try_module_get(module)) { + kfree_const(fw_work->name); + 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; +} +EXPORT_SYMBOL(request_firmware_nowait); + +#ifdef CONFIG_FW_CACHE +static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain); + +/** + * 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 + * + */ +static 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; +} + +static struct fw_priv *lookup_fw_priv(const char *fw_name) +{ + struct fw_priv *tmp; + struct firmware_cache *fwc = &fw_cache; + + spin_lock(&fwc->lock); + tmp = __lookup_fw_priv(fw_name); + spin_unlock(&fwc->lock); + + return tmp; +} + +/** + * 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 + * + */ +static int uncache_firmware(const char *fw_name) +{ + struct fw_priv *fw_priv; + struct firmware fw; + + pr_debug("%s: %s\n", __func__, fw_name); + + if (firmware_request_builtin(&fw, fw_name)) + return 0; + + fw_priv = lookup_fw_priv(fw_name); + if (fw_priv) { + free_fw_priv(fw_priv); + return 0; + } + + return -EINVAL; +} + +static struct fw_cache_entry *alloc_fw_cache_entry(const char *name) +{ + struct fw_cache_entry *fce; + + fce = kzalloc(sizeof(*fce), GFP_ATOMIC); + if (!fce) + goto exit; + + fce->name = kstrdup_const(name, GFP_ATOMIC); + if (!fce->name) { + kfree(fce); + fce = NULL; + goto exit; + } +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 void fw_cache_piggyback_on_request(struct fw_priv *fw_priv) +{ + const char *name = fw_priv->fw_name; + struct firmware_cache *fwc = fw_priv->fwc; + struct fw_cache_entry *fce; + + spin_lock(&fwc->name_lock); + if (__fw_entry_found(name)) + goto found; + + fce = alloc_fw_cache_entry(name); + if (fce) { + list_add(&fce->list, &fwc->fw_names); + kref_get(&fw_priv->ref); + pr_debug("%s: fw: %s\n", __func__, name); + } +found: + spin_unlock(&fwc->name_lock); +} + +static void free_fw_cache_entry(struct fw_cache_entry *fce) +{ + kfree_const(fce->name); + 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; + DEFINE_WAIT(wait); + + pr_debug("%s\n", __func__); + + /* cancel uncache work */ + cancel_delayed_work_sync(&fwc->work); + + fw_fallback_set_cache_timeout(); + + 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); + + fw_fallback_set_default_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) +{ + queue_delayed_work(system_power_efficient_wq, &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: + case PM_RESTORE_PREPARE: + /* + * kill pending fallback requests with a custom fallback + * to avoid stalling suspend. + */ + kill_pending_fw_fallback_reqs(true); + 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, +}; + +static int __init register_fw_pm_ops(void) +{ + int ret; + + 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; + ret = register_pm_notifier(&fw_cache.pm_notify); + if (ret) + return ret; + + register_syscore_ops(&fw_syscore_ops); + + return ret; +} + +static inline void unregister_fw_pm_ops(void) +{ + unregister_syscore_ops(&fw_syscore_ops); + unregister_pm_notifier(&fw_cache.pm_notify); +} +#else +static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv) +{ +} +static inline int register_fw_pm_ops(void) +{ + return 0; +} +static inline void unregister_fw_pm_ops(void) +{ +} +#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; +} + +static int fw_shutdown_notify(struct notifier_block *unused1, + unsigned long unused2, void *unused3) +{ + /* + * Kill all pending fallback requests to avoid both stalling shutdown, + * and avoid a deadlock with the usermode_lock. + */ + kill_pending_fw_fallback_reqs(false); + + return NOTIFY_DONE; +} + +static struct notifier_block fw_shutdown_nb = { + .notifier_call = fw_shutdown_notify, +}; + +static int __init firmware_class_init(void) +{ + int ret; + + /* No need to unfold these on exit */ + fw_cache_init(); + + ret = register_fw_pm_ops(); + if (ret) + return ret; + + ret = register_reboot_notifier(&fw_shutdown_nb); + if (ret) + goto out; + + return register_sysfs_loader(); + +out: + unregister_fw_pm_ops(); + return ret; +} + +static void __exit firmware_class_exit(void) +{ + unregister_fw_pm_ops(); + unregister_reboot_notifier(&fw_shutdown_nb); + unregister_sysfs_loader(); +} + +fs_initcall(firmware_class_init); +module_exit(firmware_class_exit); diff --git a/drivers/base/firmware_loader/sysfs.c b/drivers/base/firmware_loader/sysfs.c new file mode 100644 index 000000000..c9c93b47d --- /dev/null +++ b/drivers/base/firmware_loader/sysfs.c @@ -0,0 +1,419 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/highmem.h> +#include <linux/module.h> +#include <linux/security.h> +#include <linux/slab.h> +#include <linux/types.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(const struct class *class, const 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(const struct class *class, const 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(const 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(const struct device *dev, struct kobj_uevent_env *env) +{ + const 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); + + if (fw_sysfs->fw_upload_priv) + fw_upload_free(fw_sysfs); + + 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, +}; + +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); + + /* + * If this is a user-initiated firmware upload + * then start the upload in a worker thread now. + */ + rc = fw_upload_start(fw_sysfs); + if (rc) + written = rc; + } + break; + } + fallthrough; + default: + dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading); + fallthrough; + case -1: + fw_load_abort(fw_sysfs); + if (fw_sysfs->fw_upload_priv) + fw_state_init(fw_sysfs->fw_priv); + + break; + } +out: + mutex_unlock(&fw_lock); + return written; +} + +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) { + 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); + + if (read) + memcpy_from_page(buffer, fw_priv->pages[page_nr], + page_ofs, page_cnt); + else + memcpy_to_page(fw_priv->pages[page_nr], page_ofs, + buffer, page_cnt); + + 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, +#ifdef CONFIG_FW_UPLOAD + &dev_attr_cancel.attr, + &dev_attr_status.attr, + &dev_attr_error.attr, + &dev_attr_remaining_size.attr, +#endif + 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, +#ifdef CONFIG_FW_UPLOAD + .is_visible = fw_upload_is_visible, +#endif +}; + +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 000000000..2060add8e --- /dev/null +++ b/drivers/base/firmware_loader/sysfs.h @@ -0,0 +1,118 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __FIRMWARE_SYSFS_H +#define __FIRMWARE_SYSFS_H + +#include <linux/device.h> + +#include "firmware.h" + +MODULE_IMPORT_NS(FIRMWARE_LOADER_PRIVATE); + +extern struct firmware_fallback_config fw_fallback_config; +extern struct device_attribute dev_attr_loading; + +#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; +} +#endif + +#ifdef CONFIG_FW_LOADER_SYSFS +int register_sysfs_loader(void); +void unregister_sysfs_loader(void); +#if defined(CONFIG_FW_LOADER_USER_HELPER) && defined(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_FW_LOADER_USER_HELPER && CONFIG_SYSCTL */ +#else /* CONFIG_FW_LOADER_SYSFS */ +static inline int register_sysfs_loader(void) +{ + return 0; +} + +static inline void unregister_sysfs_loader(void) +{ +} +#endif /* CONFIG_FW_LOADER_SYSFS */ + +struct fw_sysfs { + bool nowait; + struct device dev; + struct fw_priv *fw_priv; + struct firmware *fw; + void *fw_upload_priv; +}; +#define to_fw_sysfs(__dev) container_of_const(__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); + +#ifdef CONFIG_FW_UPLOAD +extern struct device_attribute dev_attr_status; +extern struct device_attribute dev_attr_error; +extern struct device_attribute dev_attr_cancel; +extern struct device_attribute dev_attr_remaining_size; + +int fw_upload_start(struct fw_sysfs *fw_sysfs); +void fw_upload_free(struct fw_sysfs *fw_sysfs); +umode_t fw_upload_is_visible(struct kobject *kobj, struct attribute *attr, int n); +#else +static inline int fw_upload_start(struct fw_sysfs *fw_sysfs) +{ + return 0; +} + +static inline void fw_upload_free(struct fw_sysfs *fw_sysfs) +{ +} +#endif + +#endif /* __FIRMWARE_SYSFS_H */ diff --git a/drivers/base/firmware_loader/sysfs_upload.c b/drivers/base/firmware_loader/sysfs_upload.c new file mode 100644 index 000000000..a0af8f5f1 --- /dev/null +++ b/drivers/base/firmware_loader/sysfs_upload.c @@ -0,0 +1,407 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/firmware.h> +#include <linux/module.h> +#include <linux/slab.h> + +#include "sysfs_upload.h" + +/* + * Support for user-space to initiate a firmware upload to a device. + */ + +static const char * const fw_upload_prog_str[] = { + [FW_UPLOAD_PROG_IDLE] = "idle", + [FW_UPLOAD_PROG_RECEIVING] = "receiving", + [FW_UPLOAD_PROG_PREPARING] = "preparing", + [FW_UPLOAD_PROG_TRANSFERRING] = "transferring", + [FW_UPLOAD_PROG_PROGRAMMING] = "programming" +}; + +static const char * const fw_upload_err_str[] = { + [FW_UPLOAD_ERR_NONE] = "none", + [FW_UPLOAD_ERR_HW_ERROR] = "hw-error", + [FW_UPLOAD_ERR_TIMEOUT] = "timeout", + [FW_UPLOAD_ERR_CANCELED] = "user-abort", + [FW_UPLOAD_ERR_BUSY] = "device-busy", + [FW_UPLOAD_ERR_INVALID_SIZE] = "invalid-file-size", + [FW_UPLOAD_ERR_RW_ERROR] = "read-write-error", + [FW_UPLOAD_ERR_WEAROUT] = "flash-wearout", +}; + +static const char *fw_upload_progress(struct device *dev, + enum fw_upload_prog prog) +{ + const char *status = "unknown-status"; + + if (prog < FW_UPLOAD_PROG_MAX) + status = fw_upload_prog_str[prog]; + else + dev_err(dev, "Invalid status during secure update: %d\n", prog); + + return status; +} + +static const char *fw_upload_error(struct device *dev, + enum fw_upload_err err_code) +{ + const char *error = "unknown-error"; + + if (err_code < FW_UPLOAD_ERR_MAX) + error = fw_upload_err_str[err_code]; + else + dev_err(dev, "Invalid error code during secure update: %d\n", + err_code); + + return error; +} + +static ssize_t +status_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct fw_upload_priv *fwlp = to_fw_sysfs(dev)->fw_upload_priv; + + return sysfs_emit(buf, "%s\n", fw_upload_progress(dev, fwlp->progress)); +} +DEVICE_ATTR_RO(status); + +static ssize_t +error_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct fw_upload_priv *fwlp = to_fw_sysfs(dev)->fw_upload_priv; + int ret; + + mutex_lock(&fwlp->lock); + + if (fwlp->progress != FW_UPLOAD_PROG_IDLE) + ret = -EBUSY; + else if (!fwlp->err_code) + ret = 0; + else + ret = sysfs_emit(buf, "%s:%s\n", + fw_upload_progress(dev, fwlp->err_progress), + fw_upload_error(dev, fwlp->err_code)); + + mutex_unlock(&fwlp->lock); + + return ret; +} +DEVICE_ATTR_RO(error); + +static ssize_t cancel_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct fw_upload_priv *fwlp = to_fw_sysfs(dev)->fw_upload_priv; + int ret = count; + bool cancel; + + if (kstrtobool(buf, &cancel) || !cancel) + return -EINVAL; + + mutex_lock(&fwlp->lock); + if (fwlp->progress == FW_UPLOAD_PROG_IDLE) + ret = -ENODEV; + + fwlp->ops->cancel(fwlp->fw_upload); + mutex_unlock(&fwlp->lock); + + return ret; +} +DEVICE_ATTR_WO(cancel); + +static ssize_t remaining_size_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct fw_upload_priv *fwlp = to_fw_sysfs(dev)->fw_upload_priv; + + return sysfs_emit(buf, "%u\n", fwlp->remaining_size); +} +DEVICE_ATTR_RO(remaining_size); + +umode_t +fw_upload_is_visible(struct kobject *kobj, struct attribute *attr, int n) +{ + static struct fw_sysfs *fw_sysfs; + + fw_sysfs = to_fw_sysfs(kobj_to_dev(kobj)); + + if (fw_sysfs->fw_upload_priv || attr == &dev_attr_loading.attr) + return attr->mode; + + return 0; +} + +static void fw_upload_update_progress(struct fw_upload_priv *fwlp, + enum fw_upload_prog new_progress) +{ + mutex_lock(&fwlp->lock); + fwlp->progress = new_progress; + mutex_unlock(&fwlp->lock); +} + +static void fw_upload_set_error(struct fw_upload_priv *fwlp, + enum fw_upload_err err_code) +{ + mutex_lock(&fwlp->lock); + fwlp->err_progress = fwlp->progress; + fwlp->err_code = err_code; + mutex_unlock(&fwlp->lock); +} + +static void fw_upload_prog_complete(struct fw_upload_priv *fwlp) +{ + mutex_lock(&fwlp->lock); + fwlp->progress = FW_UPLOAD_PROG_IDLE; + mutex_unlock(&fwlp->lock); +} + +static void fw_upload_main(struct work_struct *work) +{ + struct fw_upload_priv *fwlp; + struct fw_sysfs *fw_sysfs; + u32 written = 0, offset = 0; + enum fw_upload_err ret; + struct device *fw_dev; + struct fw_upload *fwl; + + fwlp = container_of(work, struct fw_upload_priv, work); + fwl = fwlp->fw_upload; + fw_sysfs = (struct fw_sysfs *)fwl->priv; + fw_dev = &fw_sysfs->dev; + + fw_upload_update_progress(fwlp, FW_UPLOAD_PROG_PREPARING); + ret = fwlp->ops->prepare(fwl, fwlp->data, fwlp->remaining_size); + if (ret != FW_UPLOAD_ERR_NONE) { + fw_upload_set_error(fwlp, ret); + goto putdev_exit; + } + + fw_upload_update_progress(fwlp, FW_UPLOAD_PROG_TRANSFERRING); + while (fwlp->remaining_size) { + ret = fwlp->ops->write(fwl, fwlp->data, offset, + fwlp->remaining_size, &written); + if (ret != FW_UPLOAD_ERR_NONE || !written) { + if (ret == FW_UPLOAD_ERR_NONE) { + dev_warn(fw_dev, "write-op wrote zero data\n"); + ret = FW_UPLOAD_ERR_RW_ERROR; + } + fw_upload_set_error(fwlp, ret); + goto done; + } + + fwlp->remaining_size -= written; + offset += written; + } + + fw_upload_update_progress(fwlp, FW_UPLOAD_PROG_PROGRAMMING); + ret = fwlp->ops->poll_complete(fwl); + if (ret != FW_UPLOAD_ERR_NONE) + fw_upload_set_error(fwlp, ret); + +done: + if (fwlp->ops->cleanup) + fwlp->ops->cleanup(fwl); + +putdev_exit: + put_device(fw_dev->parent); + + /* + * Note: fwlp->remaining_size is left unmodified here to provide + * additional information on errors. It will be reinitialized when + * the next firmeware upload begins. + */ + mutex_lock(&fw_lock); + fw_free_paged_buf(fw_sysfs->fw_priv); + fw_state_init(fw_sysfs->fw_priv); + mutex_unlock(&fw_lock); + fwlp->data = NULL; + fw_upload_prog_complete(fwlp); +} + +/* + * Start a worker thread to upload data to the parent driver. + * Must be called with fw_lock held. + */ +int fw_upload_start(struct fw_sysfs *fw_sysfs) +{ + struct fw_priv *fw_priv = fw_sysfs->fw_priv; + struct device *fw_dev = &fw_sysfs->dev; + struct fw_upload_priv *fwlp; + + if (!fw_sysfs->fw_upload_priv) + return 0; + + if (!fw_priv->size) { + fw_free_paged_buf(fw_priv); + fw_state_init(fw_sysfs->fw_priv); + return 0; + } + + fwlp = fw_sysfs->fw_upload_priv; + mutex_lock(&fwlp->lock); + + /* Do not interfere with an on-going fw_upload */ + if (fwlp->progress != FW_UPLOAD_PROG_IDLE) { + mutex_unlock(&fwlp->lock); + return -EBUSY; + } + + get_device(fw_dev->parent); /* released in fw_upload_main */ + + fwlp->progress = FW_UPLOAD_PROG_RECEIVING; + fwlp->err_code = 0; + fwlp->remaining_size = fw_priv->size; + fwlp->data = fw_priv->data; + + pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n", + __func__, fw_priv->fw_name, + fw_priv, fw_priv->data, + (unsigned int)fw_priv->size); + + queue_work(system_long_wq, &fwlp->work); + mutex_unlock(&fwlp->lock); + + return 0; +} + +void fw_upload_free(struct fw_sysfs *fw_sysfs) +{ + struct fw_upload_priv *fw_upload_priv = fw_sysfs->fw_upload_priv; + + free_fw_priv(fw_sysfs->fw_priv); + kfree(fw_upload_priv->fw_upload); + kfree(fw_upload_priv); +} + +/** + * firmware_upload_register() - register for the firmware upload sysfs API + * @module: kernel module of this device + * @parent: parent device instantiating firmware upload + * @name: firmware name to be associated with this device + * @ops: pointer to structure of firmware upload ops + * @dd_handle: pointer to parent driver private data + * + * @name must be unique among all users of firmware upload. The firmware + * sysfs files for this device will be found at /sys/class/firmware/@name. + * + * Return: struct fw_upload pointer or ERR_PTR() + * + **/ +struct fw_upload * +firmware_upload_register(struct module *module, struct device *parent, + const char *name, const struct fw_upload_ops *ops, + void *dd_handle) +{ + u32 opt_flags = FW_OPT_NOCACHE; + struct fw_upload *fw_upload; + struct fw_upload_priv *fw_upload_priv; + struct fw_sysfs *fw_sysfs; + struct fw_priv *fw_priv; + struct device *fw_dev; + int ret; + + if (!name || name[0] == '\0') + return ERR_PTR(-EINVAL); + + if (!ops || !ops->cancel || !ops->prepare || + !ops->write || !ops->poll_complete) { + dev_err(parent, "Attempt to register without all required ops\n"); + return ERR_PTR(-EINVAL); + } + + if (!try_module_get(module)) + return ERR_PTR(-EFAULT); + + fw_upload = kzalloc(sizeof(*fw_upload), GFP_KERNEL); + if (!fw_upload) { + ret = -ENOMEM; + goto exit_module_put; + } + + fw_upload_priv = kzalloc(sizeof(*fw_upload_priv), GFP_KERNEL); + if (!fw_upload_priv) { + ret = -ENOMEM; + goto free_fw_upload; + } + + fw_upload_priv->fw_upload = fw_upload; + fw_upload_priv->ops = ops; + mutex_init(&fw_upload_priv->lock); + fw_upload_priv->module = module; + fw_upload_priv->name = name; + fw_upload_priv->err_code = 0; + fw_upload_priv->progress = FW_UPLOAD_PROG_IDLE; + INIT_WORK(&fw_upload_priv->work, fw_upload_main); + fw_upload->dd_handle = dd_handle; + + fw_sysfs = fw_create_instance(NULL, name, parent, opt_flags); + if (IS_ERR(fw_sysfs)) { + ret = PTR_ERR(fw_sysfs); + goto free_fw_upload_priv; + } + fw_upload->priv = fw_sysfs; + fw_sysfs->fw_upload_priv = fw_upload_priv; + fw_dev = &fw_sysfs->dev; + + ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, NULL, 0, 0, + FW_OPT_NOCACHE); + if (ret != 0) { + if (ret > 0) + ret = -EINVAL; + goto free_fw_sysfs; + } + fw_priv->is_paged_buf = true; + fw_sysfs->fw_priv = fw_priv; + + ret = device_add(fw_dev); + if (ret) { + dev_err(fw_dev, "%s: device_register failed\n", __func__); + put_device(fw_dev); + goto exit_module_put; + } + + return fw_upload; + +free_fw_sysfs: + kfree(fw_sysfs); + +free_fw_upload_priv: + kfree(fw_upload_priv); + +free_fw_upload: + kfree(fw_upload); + +exit_module_put: + module_put(module); + + return ERR_PTR(ret); +} +EXPORT_SYMBOL_GPL(firmware_upload_register); + +/** + * firmware_upload_unregister() - Unregister firmware upload interface + * @fw_upload: pointer to struct fw_upload + **/ +void firmware_upload_unregister(struct fw_upload *fw_upload) +{ + struct fw_sysfs *fw_sysfs = fw_upload->priv; + struct fw_upload_priv *fw_upload_priv = fw_sysfs->fw_upload_priv; + struct module *module = fw_upload_priv->module; + + mutex_lock(&fw_upload_priv->lock); + if (fw_upload_priv->progress == FW_UPLOAD_PROG_IDLE) { + mutex_unlock(&fw_upload_priv->lock); + goto unregister; + } + + fw_upload_priv->ops->cancel(fw_upload); + mutex_unlock(&fw_upload_priv->lock); + + /* Ensure lower-level device-driver is finished */ + flush_work(&fw_upload_priv->work); + +unregister: + device_unregister(&fw_sysfs->dev); + module_put(module); +} +EXPORT_SYMBOL_GPL(firmware_upload_unregister); diff --git a/drivers/base/firmware_loader/sysfs_upload.h b/drivers/base/firmware_loader/sysfs_upload.h new file mode 100644 index 000000000..31931ff78 --- /dev/null +++ b/drivers/base/firmware_loader/sysfs_upload.h @@ -0,0 +1,41 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __SYSFS_UPLOAD_H +#define __SYSFS_UPLOAD_H + +#include <linux/device.h> + +#include "sysfs.h" + +/** + * enum fw_upload_prog - firmware upload progress codes + * @FW_UPLOAD_PROG_IDLE: there is no firmware upload in progress + * @FW_UPLOAD_PROG_RECEIVING: worker thread is receiving firmware data + * @FW_UPLOAD_PROG_PREPARING: target device is preparing for firmware upload + * @FW_UPLOAD_PROG_TRANSFERRING: data is being copied to the device + * @FW_UPLOAD_PROG_PROGRAMMING: device is performing the firmware update + * @FW_UPLOAD_PROG_MAX: Maximum progress code marker + */ +enum fw_upload_prog { + FW_UPLOAD_PROG_IDLE, + FW_UPLOAD_PROG_RECEIVING, + FW_UPLOAD_PROG_PREPARING, + FW_UPLOAD_PROG_TRANSFERRING, + FW_UPLOAD_PROG_PROGRAMMING, + FW_UPLOAD_PROG_MAX +}; + +struct fw_upload_priv { + struct fw_upload *fw_upload; + struct module *module; + const char *name; + const struct fw_upload_ops *ops; + struct mutex lock; /* protect data structure contents */ + struct work_struct work; + const u8 *data; /* pointer to update data */ + u32 remaining_size; /* size remaining to transfer */ + enum fw_upload_prog progress; + enum fw_upload_prog err_progress; /* progress at time of failure */ + enum fw_upload_err err_code; /* security manager error code */ +}; + +#endif /* __SYSFS_UPLOAD_H */ |