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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/base/firmware_loader/sysfs.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/base/firmware_loader/sysfs.c')
-rw-r--r-- | drivers/base/firmware_loader/sysfs.c | 419 |
1 files changed, 419 insertions, 0 deletions
diff --git a/drivers/base/firmware_loader/sysfs.c b/drivers/base/firmware_loader/sysfs.c new file mode 100644 index 000000000..5b66b3d1f --- /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(struct class *class, struct class_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "%d\n", __firmware_loading_timeout()); +} + +/** + * timeout_store() - set number of seconds to wait for firmware + * @class: device class pointer + * @attr: device attribute pointer + * @buf: buffer to scan for timeout value + * @count: number of bytes in @buf + * + * Sets the number of seconds to wait for the firmware. Once + * this expires an error will be returned to the driver and no + * firmware will be provided. + * + * Note: zero means 'wait forever'. + **/ +static ssize_t timeout_store(struct class *class, struct class_attribute *attr, + const char *buf, size_t count) +{ + int tmp_loading_timeout = simple_strtol(buf, NULL, 10); + + if (tmp_loading_timeout < 0) + tmp_loading_timeout = 0; + + __fw_fallback_set_timeout(tmp_loading_timeout); + + return count; +} +static CLASS_ATTR_RW(timeout); + +static struct attribute *firmware_class_attrs[] = { + &class_attr_timeout.attr, + NULL, +}; +ATTRIBUTE_GROUPS(firmware_class); + +static int do_firmware_uevent(struct fw_sysfs *fw_sysfs, struct kobj_uevent_env *env) +{ + if (add_uevent_var(env, "FIRMWARE=%s", fw_sysfs->fw_priv->fw_name)) + return -ENOMEM; + if (add_uevent_var(env, "TIMEOUT=%i", __firmware_loading_timeout())) + return -ENOMEM; + if (add_uevent_var(env, "ASYNC=%d", fw_sysfs->nowait)) + return -ENOMEM; + + return 0; +} + +static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env) +{ + struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev); + int err = 0; + + mutex_lock(&fw_lock); + if (fw_sysfs->fw_priv) + err = do_firmware_uevent(fw_sysfs, env); + mutex_unlock(&fw_lock); + return err; +} +#endif /* CONFIG_FW_LOADER_USER_HELPER */ + +static void fw_dev_release(struct device *dev) +{ + struct fw_sysfs *fw_sysfs = to_fw_sysfs(dev); + + 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; +} |