Add request_partial_firmware_into_buf to allow for portions of firmware file to be read into a buffer. Necessary where firmware needs to be loaded in portions from file in memory constrained systems.
Signed-off-by: Scott Branden <[email protected]> --- drivers/base/firmware_loader/firmware.h | 5 ++ drivers/base/firmware_loader/main.c | 79 +++++++++++++++++++------ include/linux/firmware.h | 12 ++++ 3 files changed, 79 insertions(+), 17 deletions(-) diff --git a/drivers/base/firmware_loader/firmware.h b/drivers/base/firmware_loader/firmware.h index 933e2192fbe8..b5487f66dc45 100644 --- a/drivers/base/firmware_loader/firmware.h +++ b/drivers/base/firmware_loader/firmware.h @@ -32,6 +32,8 @@ * @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), @@ -41,6 +43,7 @@ enum fw_opt { 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 { @@ -68,6 +71,8 @@ struct fw_priv { 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; diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c index ca871b13524e..82c29c1f85c6 100644 --- a/drivers/base/firmware_loader/main.c +++ b/drivers/base/firmware_loader/main.c @@ -167,7 +167,10 @@ static int fw_cache_piggyback_on_request(const char *name); static struct fw_priv *__allocate_fw_priv(const char *fw_name, struct firmware_cache *fwc, - void *dbuf, size_t size) + void *dbuf, + size_t size, + size_t offset, + u32 opt_flags) { struct fw_priv *fw_priv; @@ -185,6 +188,8 @@ static struct fw_priv *__allocate_fw_priv(const char *fw_name, 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); @@ -209,8 +214,11 @@ static struct fw_priv *__lookup_fw_priv(const char *fw_name) /* Returns 1 for batching firmware requests with the same name */ static int alloc_lookup_fw_priv(const char *fw_name, struct firmware_cache *fwc, - struct fw_priv **fw_priv, void *dbuf, - size_t size, u32 opt_flags) + struct fw_priv **fw_priv, + void *dbuf, + size_t size, + size_t offset, + u32 opt_flags) { struct fw_priv *tmp; @@ -226,7 +234,7 @@ static int alloc_lookup_fw_priv(const char *fw_name, } } - tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size); + 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)) @@ -472,7 +480,11 @@ fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, /* Already populated data member means we're loading into a buffer */ if (!decompress && fw_priv->data) { buffer = fw_priv->data; - id = READING_FIRMWARE_PREALLOC_BUFFER; + if (fw_priv->opt_flags & FW_OPT_PARTIAL) + id = READING_FIRMWARE_PARTIAL_READ; + else + id = READING_FIRMWARE_PREALLOC_BUFFER; + msize = fw_priv->allocated_size; } @@ -495,8 +507,10 @@ fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv, fw_priv->size = 0; /* load firmware files from the mount namespace of init */ - rc = kernel_read_file_from_path_initns(path, &buffer, - &size, msize, id); + rc = kernel_pread_file_from_path_initns(path, &buffer, + &size, msize, + fw_priv->offset, + id); if (rc) { if (rc != -ENOENT) dev_warn(device, "loading %s failed with error %d\n", @@ -683,7 +697,7 @@ int assign_fw(struct firmware *fw, struct device *device, u32 opt_flags) static int _request_firmware_prepare(struct firmware **firmware_p, const char *name, struct device *device, void *dbuf, size_t size, - u32 opt_flags) + size_t offset, u32 opt_flags) { struct firmware *firmware; struct fw_priv *fw_priv; @@ -702,7 +716,7 @@ _request_firmware_prepare(struct firmware **firmware_p, const char *name, } ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size, - opt_flags); + offset, opt_flags); /* * bind with 'priv' now to avoid warning in failure path @@ -749,7 +763,7 @@ static void fw_abort_batch_reqs(struct firmware *fw) static int _request_firmware(const struct firmware **firmware_p, const char *name, struct device *device, void *buf, size_t size, - u32 opt_flags) + size_t offset, u32 opt_flags) { struct firmware *fw = NULL; int ret; @@ -763,7 +777,7 @@ _request_firmware(const struct firmware **firmware_p, const char *name, } ret = _request_firmware_prepare(&fw, name, device, buf, size, - opt_flags); + offset, opt_flags); if (ret <= 0) /* error or already assigned */ goto out; @@ -825,7 +839,7 @@ request_firmware(const struct firmware **firmware_p, const char *name, /* Need to pin this module until return */ __module_get(THIS_MODULE); - ret = _request_firmware(firmware_p, name, device, NULL, 0, + ret = _request_firmware(firmware_p, name, device, NULL, 0, 0, FW_OPT_UEVENT); module_put(THIS_MODULE); return ret; @@ -852,7 +866,7 @@ int firmware_request_nowarn(const struct firmware **firmware, const char *name, /* Need to pin this module until return */ __module_get(THIS_MODULE); - ret = _request_firmware(firmware, name, device, NULL, 0, + ret = _request_firmware(firmware, name, device, NULL, 0, 0, FW_OPT_UEVENT | FW_OPT_NO_WARN); module_put(THIS_MODULE); return ret; @@ -876,7 +890,7 @@ int request_firmware_direct(const struct firmware **firmware_p, int ret; __module_get(THIS_MODULE); - ret = _request_firmware(firmware_p, name, device, NULL, 0, + 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); @@ -901,7 +915,7 @@ int firmware_request_platform(const struct firmware **firmware, /* Need to pin this module until return */ __module_get(THIS_MODULE); - ret = _request_firmware(firmware, name, device, NULL, 0, + ret = _request_firmware(firmware, name, device, NULL, 0, 0, FW_OPT_UEVENT | FW_OPT_FALLBACK_PLATFORM); module_put(THIS_MODULE); return ret; @@ -957,13 +971,44 @@ request_firmware_into_buf(const struct firmware **firmware_p, const char *name, return -EOPNOTSUPP; __module_get(THIS_MODULE); - ret = _request_firmware(firmware_p, name, device, buf, size, + 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 @@ -996,7 +1041,7 @@ static void request_firmware_work_func(struct work_struct *work) fw_work = container_of(work, struct firmware_work, work); - _request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0, + _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() */ diff --git a/include/linux/firmware.h b/include/linux/firmware.h index cb3e2c06ed8a..c15acadc6cf4 100644 --- a/include/linux/firmware.h +++ b/include/linux/firmware.h @@ -53,6 +53,9 @@ int request_firmware_direct(const struct firmware **fw, const char *name, struct device *device); int request_firmware_into_buf(const struct firmware **firmware_p, const char *name, struct device *device, void *buf, size_t size); +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); void release_firmware(const struct firmware *fw); #else @@ -102,6 +105,15 @@ static inline int request_firmware_into_buf(const struct firmware **firmware_p, return -EINVAL; } +static inline 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) +{ + return -EINVAL; +} + #endif int firmware_request_cache(struct device *device, const char *name); -- 2.17.1
