// 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 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #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; int rc = -ENOENT; char *path; 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; len = snprintf(path, PATH_MAX, "%s/%s%s", 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); } /* 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); #ifdef CONFIG_GENTOO_PRINT_FIRMWARE_INFO printk(KERN_NOTICE "Loading firmware: %s\n", name); #endif 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; } *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);