drivers/base/firmware_loader/sysfs_upload.c

   1 // SPDX-License-Identifier: GPL-2.0
   2
   3 #include <linux/firmware.h>
   4 #include <linux/module.h>
   5 #include <linux/slab.h>
   6
   7 #include "sysfs_upload.h"
   8
   9 /*
  10  * Support for user-space to initiate a firmware upload to a device.
  11  */
  12
  13 static const char * const fw_upload_prog_str[] = {
  14         [FW_UPLOAD_PROG_IDLE]         = "idle",
  15         [FW_UPLOAD_PROG_RECEIVING]    = "receiving",
  16         [FW_UPLOAD_PROG_PREPARING]    = "preparing",
  17         [FW_UPLOAD_PROG_TRANSFERRING] = "transferring",
  18         [FW_UPLOAD_PROG_PROGRAMMING]  = "programming"
  19 };
  20
  21 static const char * const fw_upload_err_str[] = {
  22         [FW_UPLOAD_ERR_NONE]         = "none",
  23         [FW_UPLOAD_ERR_HW_ERROR]     = "hw-error",
  24         [FW_UPLOAD_ERR_TIMEOUT]      = "timeout",
  25         [FW_UPLOAD_ERR_CANCELED]     = "user-abort",
  26         [FW_UPLOAD_ERR_BUSY]         = "device-busy",
  27         [FW_UPLOAD_ERR_INVALID_SIZE] = "invalid-file-size",
  28         [FW_UPLOAD_ERR_RW_ERROR]     = "read-write-error",
  29         [FW_UPLOAD_ERR_WEAROUT]      = "flash-wearout",
  30         [FW_UPLOAD_ERR_FW_INVALID]   = "firmware-invalid",
  31 };
  32
  33 static const char *fw_upload_progress(struct device *dev,
  34                                       enum fw_upload_prog prog)
  35 {
  36         const char *status = "unknown-status";
  37
  38         if (prog < FW_UPLOAD_PROG_MAX)
  39                 status = fw_upload_prog_str[prog];
  40         else
  41                 dev_err(dev, "Invalid status during secure update: %d\n", prog);
  42
  43         return status;
  44 }
  45
  46 static const char *fw_upload_error(struct device *dev,
  47                                    enum fw_upload_err err_code)
  48 {
  49         const char *error = "unknown-error";
  50
  51         if (err_code < FW_UPLOAD_ERR_MAX)
  52                 error = fw_upload_err_str[err_code];
  53         else
  54                 dev_err(dev, "Invalid error code during secure update: %d\n",
  55                         err_code);
  56
  57         return error;
  58 }
  59
  60 static ssize_t
  61 status_show(struct device *dev, struct device_attribute *attr, char *buf)
  62 {
  63         struct fw_upload_priv *fwlp = to_fw_sysfs(dev)->fw_upload_priv;
  64
  65         return sysfs_emit(buf, "%s\n", fw_upload_progress(dev, fwlp->progress));
  66 }
  67 DEVICE_ATTR_RO(status);
  68
  69 static ssize_t
  70 error_show(struct device *dev, struct device_attribute *attr, char *buf)
  71 {
  72         struct fw_upload_priv *fwlp = to_fw_sysfs(dev)->fw_upload_priv;
  73         int ret;
  74
  75         mutex_lock(&fwlp->lock);
  76
  77         if (fwlp->progress != FW_UPLOAD_PROG_IDLE)
  78                 ret = -EBUSY;
  79         else if (!fwlp->err_code)
  80                 ret = 0;
  81         else
  82                 ret = sysfs_emit(buf, "%s:%s\n",
  83                                  fw_upload_progress(dev, fwlp->err_progress),
  84                                  fw_upload_error(dev, fwlp->err_code));
  85
  86         mutex_unlock(&fwlp->lock);
  87
  88         return ret;
  89 }
  90 DEVICE_ATTR_RO(error);
  91
  92 static ssize_t cancel_store(struct device *dev, struct device_attribute *attr,
  93                             const char *buf, size_t count)
  94 {
  95         struct fw_upload_priv *fwlp = to_fw_sysfs(dev)->fw_upload_priv;
  96         int ret = count;
  97         bool cancel;
  98
  99         if (kstrtobool(buf, &cancel) || !cancel)
 100                 return -EINVAL;
 101
 102         mutex_lock(&fwlp->lock);
 103         if (fwlp->progress == FW_UPLOAD_PROG_IDLE)
 104                 ret = -ENODEV;
 105
 106         fwlp->ops->cancel(fwlp->fw_upload);
 107         mutex_unlock(&fwlp->lock);
 108
 109         return ret;
 110 }
 111 DEVICE_ATTR_WO(cancel);
 112
 113 static ssize_t remaining_size_show(struct device *dev,
 114                                    struct device_attribute *attr, char *buf)
 115 {
 116         struct fw_upload_priv *fwlp = to_fw_sysfs(dev)->fw_upload_priv;
 117
 118         return sysfs_emit(buf, "%u\n", fwlp->remaining_size);
 119 }
 120 DEVICE_ATTR_RO(remaining_size);
 121
 122 umode_t
 123 fw_upload_is_visible(struct kobject *kobj, struct attribute *attr, int n)
 124 {
 125         static struct fw_sysfs *fw_sysfs;
 126
 127         fw_sysfs = to_fw_sysfs(kobj_to_dev(kobj));
 128
 129         if (fw_sysfs->fw_upload_priv || attr == &dev_attr_loading.attr)
 130                 return attr->mode;
 131
 132         return 0;
 133 }
 134
 135 static void fw_upload_update_progress(struct fw_upload_priv *fwlp,
 136                                       enum fw_upload_prog new_progress)
 137 {
 138         mutex_lock(&fwlp->lock);
 139         fwlp->progress = new_progress;
 140         mutex_unlock(&fwlp->lock);
 141 }
 142
 143 static void fw_upload_set_error(struct fw_upload_priv *fwlp,
 144                                 enum fw_upload_err err_code)
 145 {
 146         mutex_lock(&fwlp->lock);
 147         fwlp->err_progress = fwlp->progress;
 148         fwlp->err_code = err_code;
 149         mutex_unlock(&fwlp->lock);
 150 }
 151
 152 static void fw_upload_prog_complete(struct fw_upload_priv *fwlp)
 153 {
 154         mutex_lock(&fwlp->lock);
 155         fwlp->progress = FW_UPLOAD_PROG_IDLE;
 156         mutex_unlock(&fwlp->lock);
 157 }
 158
 159 static void fw_upload_main(struct work_struct *work)
 160 {
 161         struct fw_upload_priv *fwlp;
 162         struct fw_sysfs *fw_sysfs;
 163         u32 written = 0, offset = 0;
 164         enum fw_upload_err ret;
 165         struct device *fw_dev;
 166         struct fw_upload *fwl;
 167
 168         fwlp = container_of(work, struct fw_upload_priv, work);
 169         fwl = fwlp->fw_upload;
 170         fw_sysfs = (struct fw_sysfs *)fwl->priv;
 171         fw_dev = &fw_sysfs->dev;
 172
 173         fw_upload_update_progress(fwlp, FW_UPLOAD_PROG_PREPARING);
 174         ret = fwlp->ops->prepare(fwl, fwlp->data, fwlp->remaining_size);
 175         if (ret != FW_UPLOAD_ERR_NONE) {
 176                 fw_upload_set_error(fwlp, ret);
 177                 goto putdev_exit;
 178         }
 179
 180         fw_upload_update_progress(fwlp, FW_UPLOAD_PROG_TRANSFERRING);
 181         while (fwlp->remaining_size) {
 182                 ret = fwlp->ops->write(fwl, fwlp->data, offset,
 183                                         fwlp->remaining_size, &written);
 184                 if (ret != FW_UPLOAD_ERR_NONE || !written) {
 185                         if (ret == FW_UPLOAD_ERR_NONE) {
 186                                 dev_warn(fw_dev, "write-op wrote zero data\n");
 187                                 ret = FW_UPLOAD_ERR_RW_ERROR;
 188                         }
 189                         fw_upload_set_error(fwlp, ret);
 190                         goto done;
 191                 }
 192
 193                 fwlp->remaining_size -= written;
 194                 offset += written;
 195         }
 196
 197         fw_upload_update_progress(fwlp, FW_UPLOAD_PROG_PROGRAMMING);
 198         ret = fwlp->ops->poll_complete(fwl);
 199         if (ret != FW_UPLOAD_ERR_NONE)
 200                 fw_upload_set_error(fwlp, ret);
 201
 202 done:
 203         if (fwlp->ops->cleanup)
 204                 fwlp->ops->cleanup(fwl);
 205
 206 putdev_exit:
 207         put_device(fw_dev->parent);
 208
 209         /*
 210          * Note: fwlp->remaining_size is left unmodified here to provide
 211          * additional information on errors. It will be reinitialized when
 212          * the next firmeware upload begins.
 213          */
 214         mutex_lock(&fw_lock);
 215         fw_free_paged_buf(fw_sysfs->fw_priv);
 216         fw_state_init(fw_sysfs->fw_priv);
 217         mutex_unlock(&fw_lock);
 218         fwlp->data = NULL;
 219         fw_upload_prog_complete(fwlp);
 220 }
 221
 222 /*
 223  * Start a worker thread to upload data to the parent driver.
 224  * Must be called with fw_lock held.
 225  */
 226 int fw_upload_start(struct fw_sysfs *fw_sysfs)
 227 {
 228         struct fw_priv *fw_priv = fw_sysfs->fw_priv;
 229         struct device *fw_dev = &fw_sysfs->dev;
 230         struct fw_upload_priv *fwlp;
 231
 232         if (!fw_sysfs->fw_upload_priv)
 233                 return 0;
 234
 235         if (!fw_priv->size) {
 236                 fw_free_paged_buf(fw_priv);
 237                 fw_state_init(fw_sysfs->fw_priv);
 238                 return 0;
 239         }
 240
 241         fwlp = fw_sysfs->fw_upload_priv;
 242         mutex_lock(&fwlp->lock);
 243
 244         /* Do not interfere with an on-going fw_upload */
 245         if (fwlp->progress != FW_UPLOAD_PROG_IDLE) {
 246                 mutex_unlock(&fwlp->lock);
 247                 return -EBUSY;
 248         }
 249
 250         get_device(fw_dev->parent); /* released in fw_upload_main */
 251
 252         fwlp->progress = FW_UPLOAD_PROG_RECEIVING;
 253         fwlp->err_code = 0;
 254         fwlp->remaining_size = fw_priv->size;
 255         fwlp->data = fw_priv->data;
 256
 257         pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
 258                  __func__, fw_priv->fw_name,
 259                  fw_priv, fw_priv->data,
 260                  (unsigned int)fw_priv->size);
 261
 262         queue_work(system_long_wq, &fwlp->work);
 263         mutex_unlock(&fwlp->lock);
 264
 265         return 0;
 266 }
 267
 268 void fw_upload_free(struct fw_sysfs *fw_sysfs)
 269 {
 270         struct fw_upload_priv *fw_upload_priv = fw_sysfs->fw_upload_priv;
 271
 272         free_fw_priv(fw_sysfs->fw_priv);
 273         kfree(fw_upload_priv->fw_upload);
 274         kfree(fw_upload_priv);
 275 }
 276
 277 /**
 278  * firmware_upload_register() - register for the firmware upload sysfs API
 279  * @module: kernel module of this device
 280  * @parent: parent device instantiating firmware upload
 281  * @name: firmware name to be associated with this device
 282  * @ops: pointer to structure of firmware upload ops
 283  * @dd_handle: pointer to parent driver private data
 284  *
 285  *      @name must be unique among all users of firmware upload. The firmware
 286  *      sysfs files for this device will be found at /sys/class/firmware/@name.
 287  *
 288  *      Return: struct fw_upload pointer or ERR_PTR()
 289  *
 290  **/
 291 struct fw_upload *
 292 firmware_upload_register(struct module *module, struct device *parent,
 293                          const char *name, const struct fw_upload_ops *ops,
 294                          void *dd_handle)
 295 {
 296         u32 opt_flags = FW_OPT_NOCACHE;
 297         struct fw_upload *fw_upload;
 298         struct fw_upload_priv *fw_upload_priv;
 299         struct fw_sysfs *fw_sysfs;
 300         struct fw_priv *fw_priv;
 301         struct device *fw_dev;
 302         int ret;
 303
 304         if (!name || name[0] == '\0')
 305                 return ERR_PTR(-EINVAL);
 306
 307         if (!ops || !ops->cancel || !ops->prepare ||
 308             !ops->write || !ops->poll_complete) {
 309                 dev_err(parent, "Attempt to register without all required ops\n");
 310                 return ERR_PTR(-EINVAL);
 311         }
 312
 313         if (!try_module_get(module))
 314                 return ERR_PTR(-EFAULT);
 315
 316         fw_upload = kzalloc(sizeof(*fw_upload), GFP_KERNEL);
 317         if (!fw_upload) {
 318                 ret = -ENOMEM;
 319                 goto exit_module_put;
 320         }
 321
 322         fw_upload_priv = kzalloc(sizeof(*fw_upload_priv), GFP_KERNEL);
 323         if (!fw_upload_priv) {
 324                 ret = -ENOMEM;
 325                 goto free_fw_upload;
 326         }
 327
 328         fw_upload_priv->fw_upload = fw_upload;
 329         fw_upload_priv->ops = ops;
 330         mutex_init(&fw_upload_priv->lock);
 331         fw_upload_priv->module = module;
 332         fw_upload_priv->name = name;
 333         fw_upload_priv->err_code = 0;
 334         fw_upload_priv->progress = FW_UPLOAD_PROG_IDLE;
 335         INIT_WORK(&fw_upload_priv->work, fw_upload_main);
 336         fw_upload->dd_handle = dd_handle;
 337
 338         fw_sysfs = fw_create_instance(NULL, name, parent, opt_flags);
 339         if (IS_ERR(fw_sysfs)) {
 340                 ret = PTR_ERR(fw_sysfs);
 341                 goto free_fw_upload_priv;
 342         }
 343         fw_upload->priv = fw_sysfs;
 344         fw_sysfs->fw_upload_priv = fw_upload_priv;
 345         fw_dev = &fw_sysfs->dev;
 346
 347         ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv,  NULL, 0, 0,
 348                                    FW_OPT_NOCACHE);
 349         if (ret != 0) {
 350                 if (ret > 0)
 351                         ret = -EINVAL;
 352                 goto free_fw_sysfs;
 353         }
 354         fw_priv->is_paged_buf = true;
 355         fw_sysfs->fw_priv = fw_priv;
 356
 357         ret = device_add(fw_dev);
 358         if (ret) {
 359                 dev_err(fw_dev, "%s: device_register failed\n", __func__);
 360                 put_device(fw_dev);
 361                 goto exit_module_put;
 362         }
 363
 364         return fw_upload;
 365
 366 free_fw_sysfs:
 367         kfree(fw_sysfs);
 368
 369 free_fw_upload_priv:
 370         kfree(fw_upload_priv);
 371
 372 free_fw_upload:
 373         kfree(fw_upload);
 374
 375 exit_module_put:
 376         module_put(module);
 377
 378         return ERR_PTR(ret);
 379 }
 380 EXPORT_SYMBOL_GPL(firmware_upload_register);
 381
 382 /**
 383  * firmware_upload_unregister() - Unregister firmware upload interface
 384  * @fw_upload: pointer to struct fw_upload
 385  **/
 386 void firmware_upload_unregister(struct fw_upload *fw_upload)
 387 {
 388         struct fw_sysfs *fw_sysfs = fw_upload->priv;
 389         struct fw_upload_priv *fw_upload_priv = fw_sysfs->fw_upload_priv;
 390         struct module *module = fw_upload_priv->module;
 391
 392         mutex_lock(&fw_upload_priv->lock);
 393         if (fw_upload_priv->progress == FW_UPLOAD_PROG_IDLE) {
 394                 mutex_unlock(&fw_upload_priv->lock);
 395                 goto unregister;
 396         }
 397
 398         fw_upload_priv->ops->cancel(fw_upload);
 399         mutex_unlock(&fw_upload_priv->lock);
 400
 401         /* Ensure lower-level device-driver is finished */
 402         flush_work(&fw_upload_priv->work);
 403
 404 unregister:
 405         device_unregister(&fw_sysfs->dev);
 406         module_put(module);
 407 }
 408 EXPORT_SYMBOL_GPL(firmware_upload_unregister);