target/linux/generic/pending-6.6/510-block-add-uImage.FIT-subimage-block-driver.patch

   1 From 6173a065cb395d4a9528c4e49810af127db68141 Mon Sep 17 00:00:00 2001
   2 From: Daniel Golle <daniel@makrotopia.org>
   3 Date: Wed, 16 Nov 2022 12:49:52 +0000
   4 Subject: [PATCH 1/2] block: add uImage.FIT subimage block driver
   5
   6 Add a small block driver which exposes filesystem sub-images contained
   7 in U-Boot uImage.FIT images as block devices.
   8
   9 The uImage.FIT image has to be stored directly on a block device or
  10 partition, MTD device or partition, or UBI volume.
  11
  12 The driver is intended for systems using the U-Boot bootloader and
  13 uses the root device hint left by the bootloader (or the user) in
  14 the 'chosen' section of the device-tree.
  15
  16 Example:
  17 /dts-v1/;
  18 / {
  19         chosen {
  20                 rootdisk = <&mmc0_part3>;
  21         };
  22 };
  23
  24 Signed-off-by: Daniel Golle <daniel@makrotopia.org>
  25 ---
  26  MAINTAINERS                 |   6 +
  27  drivers/block/Kconfig       |  12 +
  28  drivers/block/Makefile      |   2 +
  29  drivers/block/fitblk.c      | 658 ++++++++++++++++++++++++++++++++++++
  30  drivers/block/open          |   4 +
  31  include/uapi/linux/fitblk.h |  10 +
  32  6 files changed, 692 insertions(+)
  33  create mode 100644 drivers/block/fitblk.c
  34  create mode 100644 drivers/block/open
  35  create mode 100644 include/uapi/linux/fitblk.h
  36
  37 --- a/MAINTAINERS
  38 +++ b/MAINTAINERS
  39 @@ -22006,6 +22006,12 @@ F:     Documentation/filesystems/ubifs-authe
  40  F:     Documentation/filesystems/ubifs.rst
  41  F:     fs/ubifs/
  42
  43 +U-BOOT UIMAGE.FIT PARSER
  44 +M:     Daniel Golle <daniel@makrotopia.org>
  45 +L:     linux-block@vger.kernel.org
  46 +S:     Maintained
  47 +F:     drivers/block/fitblk.c
  48 +
  49  UBLK USERSPACE BLOCK DRIVER
  50  M:     Ming Lei <ming.lei@redhat.com>
  51  L:     linux-block@vger.kernel.org
  52 --- a/drivers/block/Kconfig
  53 +++ b/drivers/block/Kconfig
  54 @@ -354,6 +354,18 @@ config VIRTIO_BLK
  55           This is the virtual block driver for virtio.  It can be used with
  56            QEMU based VMMs (like KVM or Xen).  Say Y or M.
  57
  58 +config UIMAGE_FIT_BLK
  59 +       bool "uImage.FIT block driver"
  60 +       help
  61 +         This driver allows using filesystems contained in uImage.FIT images
  62 +         by mapping them as block devices.
  63 +
  64 +         It can currently not be built as a module due to libfdt symbols not
  65 +         being exported.
  66 +
  67 +         Say Y if you want to mount filesystems sub-images of a uImage.FIT
  68 +         stored in a block device partition, mtdblock or ubiblock device.
  69 +
  70  config BLK_DEV_RBD
  71         tristate "Rados block device (RBD)"
  72         depends on INET && BLOCK
  73 --- a/drivers/block/Makefile
  74 +++ b/drivers/block/Makefile
  75 @@ -39,4 +39,6 @@ obj-$(CONFIG_BLK_DEV_NULL_BLK)        += null_b
  76
  77  obj-$(CONFIG_BLK_DEV_UBLK)                     += ublk_drv.o
  78
  79 +obj-$(CONFIG_UIMAGE_FIT_BLK)   += fitblk.o
  80 +
  81  swim_mod-y     := swim.o swim_asm.o
  82 --- /dev/null
  83 +++ b/drivers/block/fitblk.c
  84 @@ -0,0 +1,659 @@
  85 +// SPDX-License-Identifier: GPL-2.0-only
  86 +/*
  87 + * uImage.FIT virtual block device driver.
  88 + *
  89 + * Copyright (C) 2023 Daniel Golle
  90 + * Copyright (C) 2007 Nick Piggin
  91 + * Copyright (C) 2007 Novell Inc.
  92 + *
  93 + * Initially derived from drivers/block/brd.c which is in parts derived from
  94 + * drivers/block/rd.c, and drivers/block/loop.c, copyright of their respective
  95 + * owners.
  96 + *
  97 + * uImage.FIT headers extracted from Das U-Boot
  98 + *  (C) Copyright 2008 Semihalf
  99 + *  (C) Copyright 2000-2005
 100 + *  Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 101 + */
 102 +
 103 +#include <linux/init.h>
 104 +#include <linux/initrd.h>
 105 +#include <linux/module.h>
 106 +#include <linux/moduleparam.h>
 107 +#include <linux/major.h>
 108 +#include <linux/blkdev.h>
 109 +#include <linux/blkpg.h>
 110 +#include <linux/blk-mq.h>
 111 +#include <linux/ctype.h>
 112 +#include <linux/hdreg.h>
 113 +#include <linux/list.h>
 114 +#include <linux/mutex.h>
 115 +#include <linux/of.h>
 116 +#include <linux/of_device.h>
 117 +#include <linux/of_fdt.h>
 118 +#include <linux/pagemap.h>
 119 +#include <linux/platform_device.h>
 120 +#include <linux/property.h>
 121 +#include <linux/refcount.h>
 122 +#include <linux/task_work.h>
 123 +#include <linux/types.h>
 124 +#include <linux/libfdt.h>
 125 +#include <linux/mtd/mtd.h>
 126 +#include <linux/root_dev.h>
 127 +#include <uapi/linux/fitblk.h>
 128 +
 129 +#define FIT_DEVICE_PREFIX      "fit"
 130 +
 131 +/* maximum number of pages used for the uImage.FIT index structure */
 132 +#define FIT_MAX_PAGES          1024
 133 +
 134 +/* minimum free sectors to map as read-write "remainder" volume */
 135 +#define MIN_FREE_SECT          16
 136 +
 137 +/* maximum number of mapped loadables */
 138 +#define MAX_FIT_LOADABLES      16
 139 +
 140 +/* constants for uImage.FIT structrure traversal */
 141 +#define FIT_IMAGES_PATH                "/images"
 142 +#define FIT_CONFS_PATH         "/configurations"
 143 +
 144 +/* hash/signature/key node */
 145 +#define FIT_HASH_NODENAME      "hash"
 146 +#define FIT_ALGO_PROP          "algo"
 147 +#define FIT_VALUE_PROP         "value"
 148 +#define FIT_IGNORE_PROP                "uboot-ignore"
 149 +#define FIT_SIG_NODENAME       "signature"
 150 +#define FIT_KEY_REQUIRED       "required"
 151 +#define FIT_KEY_HINT           "key-name-hint"
 152 +
 153 +/* cipher node */
 154 +#define FIT_CIPHER_NODENAME    "cipher"
 155 +#define FIT_ALGO_PROP          "algo"
 156 +
 157 +/* image node */
 158 +#define FIT_DATA_PROP          "data"
 159 +#define FIT_DATA_POSITION_PROP "data-position"
 160 +#define FIT_DATA_OFFSET_PROP   "data-offset"
 161 +#define FIT_DATA_SIZE_PROP     "data-size"
 162 +#define FIT_TIMESTAMP_PROP     "timestamp"
 163 +#define FIT_DESC_PROP          "description"
 164 +#define FIT_ARCH_PROP          "arch"
 165 +#define FIT_TYPE_PROP          "type"
 166 +#define FIT_OS_PROP            "os"
 167 +#define FIT_COMP_PROP          "compression"
 168 +#define FIT_ENTRY_PROP         "entry"
 169 +#define FIT_LOAD_PROP          "load"
 170 +
 171 +/* configuration node */
 172 +#define FIT_KERNEL_PROP                "kernel"
 173 +#define FIT_FILESYSTEM_PROP    "filesystem"
 174 +#define FIT_RAMDISK_PROP       "ramdisk"
 175 +#define FIT_FDT_PROP           "fdt"
 176 +#define FIT_LOADABLE_PROP      "loadables"
 177 +#define FIT_DEFAULT_PROP       "default"
 178 +#define FIT_SETUP_PROP         "setup"
 179 +#define FIT_FPGA_PROP          "fpga"
 180 +#define FIT_FIRMWARE_PROP      "firmware"
 181 +#define FIT_STANDALONE_PROP    "standalone"
 182 +
 183 +/* fitblk driver data */
 184 +static const char *_fitblk_claim_ptr = "I belong to fitblk";
 185 +static const char *ubootver;
 186 +struct device_node *rootdisk;
 187 +static struct platform_device *pdev;
 188 +static LIST_HEAD(fitblk_devices);
 189 +static DEFINE_MUTEX(devices_mutex);
 190 +refcount_t num_devs;
 191 +
 192 +struct fitblk {
 193 +       struct platform_device  *pdev;
 194 +       struct block_device     *lower_bdev;
 195 +       sector_t                start_sect;
 196 +       struct gendisk          *disk;
 197 +       struct work_struct      remove_work;
 198 +       struct list_head        list;
 199 +       bool                    dead;
 200 +};
 201 +
 202 +static int fitblk_open(struct gendisk *disk, fmode_t mode)
 203 +{
 204 +       struct fitblk *fitblk = disk->private_data;
 205 +
 206 +       if (fitblk->dead)
 207 +               return -ENOENT;
 208 +
 209 +       return 0;
 210 +}
 211 +
 212 +static void fitblk_release(struct gendisk *disk)
 213 +{
 214 +       return;
 215 +}
 216 +
 217 +static void fitblk_submit_bio(struct bio *orig_bio)
 218 +{
 219 +       struct bio *bio = orig_bio;
 220 +       struct fitblk *fitblk = bio->bi_bdev->bd_disk->private_data;
 221 +
 222 +       if (fitblk->dead)
 223 +               return;
 224 +
 225 +       /* mangle bio and re-submit */
 226 +       while (bio) {
 227 +               bio->bi_iter.bi_sector += fitblk->start_sect;
 228 +               bio->bi_bdev = fitblk->lower_bdev;
 229 +               bio = bio->bi_next;
 230 +       }
 231 +       submit_bio(orig_bio);
 232 +}
 233 +
 234 +static void fitblk_remove(struct fitblk *fitblk)
 235 +{
 236 +       blk_mark_disk_dead(fitblk->disk);
 237 +       mutex_lock(&devices_mutex);
 238 +       fitblk->dead = true;
 239 +       list_del(&fitblk->list);
 240 +       mutex_unlock(&devices_mutex);
 241 +
 242 +       schedule_work(&fitblk->remove_work);
 243 +}
 244 +
 245 +static int fitblk_ioctl(struct block_device *bdev, fmode_t mode,
 246 +                       unsigned int cmd, unsigned long arg)
 247 +{
 248 +       struct fitblk *fitblk = bdev->bd_disk->private_data;
 249 +
 250 +       if (!capable(CAP_SYS_ADMIN))
 251 +               return -EACCES;
 252 +
 253 +       if (fitblk->dead)
 254 +               return -ENOENT;
 255 +
 256 +       switch (cmd) {
 257 +       case FITBLK_RELEASE:
 258 +               fitblk_remove(fitblk);
 259 +               break;
 260 +       default:
 261 +               return -EINVAL;
 262 +       }
 263 +
 264 +       return 0;
 265 +}
 266 +
 267 +static const struct block_device_operations fitblk_fops = {
 268 +       .owner          = THIS_MODULE,
 269 +       .ioctl          = fitblk_ioctl,
 270 +       .open           = fitblk_open,
 271 +       .release        = fitblk_release,
 272 +       .submit_bio     = fitblk_submit_bio,
 273 +};
 274 +
 275 +static void fitblk_purge(struct work_struct *work)
 276 +{
 277 +       struct fitblk *fitblk = container_of(work, struct fitblk, remove_work);
 278 +
 279 +       //del_gendisk(fitblk->disk); // causes crash, not doing it doesn't matter
 280 +       refcount_dec(&num_devs);
 281 +       platform_device_del(fitblk->pdev);
 282 +       platform_device_put(fitblk->pdev);
 283 +
 284 +       if (refcount_dec_if_one(&num_devs)) {
 285 +               sysfs_remove_link(&pdev->dev.kobj, "lower_dev");
 286 +               blkdev_put(fitblk->lower_bdev, &_fitblk_claim_ptr);
 287 +       }
 288 +
 289 +       kfree(fitblk);
 290 +}
 291 +
 292 +static int add_fit_subimage_device(struct block_device *lower_bdev,
 293 +                                  unsigned int slot, sector_t start_sect,
 294 +                                  sector_t nr_sect, bool readonly)
 295 +{
 296 +       struct fitblk *fitblk;
 297 +       struct gendisk *disk;
 298 +       int err;
 299 +
 300 +       mutex_lock(&devices_mutex);
 301 +       if (!refcount_inc_not_zero(&num_devs))
 302 +               return -EBADF;
 303 +
 304 +       fitblk = kzalloc(sizeof(struct fitblk), GFP_KERNEL);
 305 +       if (!fitblk) {
 306 +               err = -ENOMEM;
 307 +               goto out_unlock;
 308 +       }
 309 +
 310 +       fitblk->lower_bdev = lower_bdev;
 311 +       fitblk->start_sect = start_sect;
 312 +       INIT_WORK(&fitblk->remove_work, fitblk_purge);
 313 +
 314 +       disk = blk_alloc_disk(NUMA_NO_NODE);
 315 +       if (!disk) {
 316 +               err = -ENOMEM;
 317 +               goto out_free_fitblk;
 318 +       }
 319 +
 320 +       disk->first_minor = 0;
 321 +       disk->flags = lower_bdev->bd_disk->flags | GENHD_FL_NO_PART;
 322 +       disk->fops = &fitblk_fops;
 323 +       disk->private_data = fitblk;
 324 +       if (readonly) {
 325 +               set_disk_ro(disk, 1);
 326 +               snprintf(disk->disk_name, sizeof(disk->disk_name), FIT_DEVICE_PREFIX "%u", slot);
 327 +       } else {
 328 +               strcpy(disk->disk_name, FIT_DEVICE_PREFIX "rw");
 329 +       }
 330 +
 331 +       set_capacity(disk, nr_sect);
 332 +
 333 +       disk->queue->queue_flags = lower_bdev->bd_disk->queue->queue_flags;
 334 +       memcpy(&disk->queue->limits, &lower_bdev->bd_disk->queue->limits,
 335 +              sizeof(struct queue_limits));
 336 +
 337 +       fitblk->disk = disk;
 338 +       fitblk->pdev = platform_device_alloc(disk->disk_name, PLATFORM_DEVID_NONE);
 339 +       if (!fitblk->pdev) {
 340 +               err = -ENOMEM;
 341 +               goto out_cleanup_disk;
 342 +       }
 343 +
 344 +       fitblk->pdev->dev.parent = &pdev->dev;
 345 +       err = platform_device_add(fitblk->pdev);
 346 +       if (err)
 347 +               goto out_put_pdev;
 348 +
 349 +       err = device_add_disk(&fitblk->pdev->dev, disk, NULL);
 350 +       if (err)
 351 +               goto out_del_pdev;
 352 +
 353 +       if (!ROOT_DEV)
 354 +               ROOT_DEV = disk->part0->bd_dev;
 355 +
 356 +       list_add_tail(&fitblk->list, &fitblk_devices);
 357 +
 358 +       mutex_unlock(&devices_mutex);
 359 +
 360 +       return 0;
 361 +
 362 +out_del_pdev:
 363 +       platform_device_del(fitblk->pdev);
 364 +out_put_pdev:
 365 +       platform_device_put(fitblk->pdev);
 366 +out_cleanup_disk:
 367 +       put_disk(disk);
 368 +out_free_fitblk:
 369 +       kfree(fitblk);
 370 +out_unlock:
 371 +       refcount_dec(&num_devs);
 372 +       mutex_unlock(&devices_mutex);
 373 +       return err;
 374 +}
 375 +
 376 +static void fitblk_mark_dead(struct block_device *bdev, bool surprise)
 377 +{
 378 +       struct list_head *n, *tmp;
 379 +       struct fitblk *fitblk;
 380 +
 381 +       mutex_lock(&devices_mutex);
 382 +       list_for_each_safe(n, tmp, &fitblk_devices) {
 383 +               fitblk = list_entry(n, struct fitblk, list);
 384 +               if (fitblk->lower_bdev != bdev)
 385 +                       continue;
 386 +
 387 +               fitblk->dead = true;
 388 +               list_del(&fitblk->list);
 389 +               /* removal needs to be deferred to avoid deadlock */
 390 +               schedule_work(&fitblk->remove_work);
 391 +       }
 392 +       mutex_unlock(&devices_mutex);
 393 +}
 394 +
 395 +static const struct blk_holder_ops fitblk_hops = {
 396 +       .mark_dead = fitblk_mark_dead,
 397 +};
 398 +
 399 +static int parse_fit_on_dev(struct device *dev)
 400 +{
 401 +       struct block_device *bdev;
 402 +       struct address_space *mapping;
 403 +       struct folio *folio;
 404 +       pgoff_t f_index = 0;
 405 +       size_t bytes_left, bytes_to_copy;
 406 +       void *pre_fit, *fit, *fit_c;
 407 +       u64 dsize, dsectors, imgmaxsect = 0;
 408 +       u32 size, image_pos, image_len;
 409 +       const __be32 *image_offset_be, *image_len_be, *image_pos_be;
 410 +       int ret = 0, node, images, config;
 411 +       const char *image_name, *image_type, *image_description,
 412 +               *config_default, *config_description, *config_loadables;
 413 +       u32 image_name_len, image_type_len, image_description_len,
 414 +               bootconf_len, config_default_len, config_description_len,
 415 +               config_loadables_len;
 416 +       sector_t start_sect, nr_sects;
 417 +       struct device_node *np = NULL;
 418 +       const char *bootconf_c;
 419 +       const char *loadable;
 420 +       char *bootconf = NULL, *bootconf_term;
 421 +       bool found;
 422 +       int loadables_rem_len, loadable_len;
 423 +       u16 loadcnt;
 424 +       unsigned int slot = 0;
 425 +
 426 +       /* Exclusive open the block device to receive holder notifications */
 427 +       bdev = blkdev_get_by_dev(dev->devt, BLK_OPEN_READ, &_fitblk_claim_ptr, &fitblk_hops);
 428 +       if (!bdev)
 429 +               return -ENODEV;
 430 +
 431 +       if (IS_ERR(bdev))
 432 +               return PTR_ERR(bdev);
 433 +
 434 +       mapping = bdev->bd_inode->i_mapping;
 435 +
 436 +       /* map first page */
 437 +       folio = read_mapping_folio(mapping, f_index++, NULL);
 438 +       if (IS_ERR(folio)) {
 439 +               ret = PTR_ERR(folio);
 440 +               goto out_blkdev;
 441 +       }
 442 +       pre_fit = folio_address(folio) + offset_in_folio(folio, 0);
 443 +
 444 +       /* uImage.FIT is based on flattened device tree structure */
 445 +       if (fdt_check_header(pre_fit)) {
 446 +               ret = -EINVAL;
 447 +               folio_put(folio);
 448 +               goto out_blkdev;
 449 +       }
 450 +
 451 +       size = fdt_totalsize(pre_fit);
 452 +
 453 +       if (size > PAGE_SIZE * FIT_MAX_PAGES) {
 454 +               ret = -EOPNOTSUPP;
 455 +               folio_put(folio);
 456 +               goto out_blkdev;
 457 +       }
 458 +
 459 +       /* acquire disk size */
 460 +       dsectors = bdev_nr_sectors(bdev);
 461 +       dsize = dsectors << SECTOR_SHIFT;
 462 +
 463 +       /* abort if FIT structure is larger than disk or partition size */
 464 +       if (size >= dsize) {
 465 +               ret = -EFBIG;
 466 +               folio_put(folio);
 467 +               goto out_blkdev;
 468 +       }
 469 +
 470 +       fit = kmalloc(size, GFP_KERNEL);
 471 +       if (!fit) {
 472 +               ret = -ENOMEM;
 473 +               folio_put(folio);
 474 +               goto out_blkdev;
 475 +       }
 476 +
 477 +       bytes_left = size;
 478 +       fit_c = fit;
 479 +       while (bytes_left > 0) {
 480 +               bytes_to_copy = min_t(size_t, bytes_left,
 481 +                                    folio_size(folio) - offset_in_folio(folio, 0));
 482 +               memcpy(fit_c, pre_fit, bytes_to_copy);
 483 +               fit_c += bytes_to_copy;
 484 +               bytes_left -= bytes_to_copy;
 485 +               if (bytes_left) {
 486 +                       folio_put(folio);
 487 +                       folio = read_mapping_folio(mapping, f_index++, NULL);
 488 +                       if (IS_ERR(folio)) {
 489 +                               ret = PTR_ERR(folio);
 490 +                               goto out_blkdev;
 491 +                       };
 492 +                       pre_fit = folio_address(folio) + offset_in_folio(folio, 0);
 493 +               }
 494 +       }
 495 +       folio_put(folio);
 496 +
 497 +       /* set boot config node name U-Boot may have added to the device tree */
 498 +       np = of_find_node_by_path("/chosen");
 499 +       if (np) {
 500 +               bootconf_c = of_get_property(np, "u-boot,bootconf", &bootconf_len);
 501 +               if (bootconf_c && bootconf_len)
 502 +                       bootconf = kmemdup_nul(bootconf_c, bootconf_len, GFP_KERNEL);
 503 +       }
 504 +
 505 +       if (bootconf) {
 506 +               bootconf_term = strchr(bootconf, '#');
 507 +               if (bootconf_term)
 508 +                       *bootconf_term = '\0';
 509 +       }
 510 +
 511 +       /* find configuration path in uImage.FIT */
 512 +       config = fdt_path_offset(fit, FIT_CONFS_PATH);
 513 +       if (config < 0) {
 514 +               pr_err("FIT: Cannot find %s node: %d\n",
 515 +                       FIT_CONFS_PATH, config);
 516 +               ret = -ENOENT;
 517 +               goto out_bootconf;
 518 +       }
 519 +
 520 +       /* get default configuration node name */
 521 +       config_default =
 522 +               fdt_getprop(fit, config, FIT_DEFAULT_PROP, &config_default_len);
 523 +
 524 +       /* make sure we got either default or selected boot config node name */
 525 +       if (!config_default && !bootconf) {
 526 +               pr_err("FIT: Cannot find default configuration\n");
 527 +               ret = -ENOENT;
 528 +               goto out_bootconf;
 529 +       }
 530 +
 531 +       /* find selected boot config node, fallback on default config node */
 532 +       node = fdt_subnode_offset(fit, config, bootconf ?: config_default);
 533 +       if (node < 0) {
 534 +               pr_err("FIT: Cannot find %s node: %d\n",
 535 +                       bootconf ?: config_default, node);
 536 +               ret = -ENOENT;
 537 +               goto out_bootconf;
 538 +       }
 539 +
 540 +       pr_info("FIT: Detected U-Boot %s\n", ubootver);
 541 +
 542 +       /* get selected configuration data */
 543 +       config_description =
 544 +               fdt_getprop(fit, node, FIT_DESC_PROP, &config_description_len);
 545 +       config_loadables = fdt_getprop(fit, node, FIT_LOADABLE_PROP,
 546 +                                      &config_loadables_len);
 547 +
 548 +       pr_info("FIT: %s configuration: \"%.*s\"%s%.*s%s\n",
 549 +               bootconf ? "Selected" : "Default",
 550 +               bootconf ? bootconf_len : config_default_len,
 551 +               bootconf ?: config_default,
 552 +               config_description ? " (" : "",
 553 +               config_description ? config_description_len : 0,
 554 +               config_description ?: "",
 555 +               config_description ? ")" : "");
 556 +
 557 +       if (!config_loadables || !config_loadables_len) {
 558 +               pr_err("FIT: No loadables configured in \"%s\"\n",
 559 +                       bootconf ?: config_default);
 560 +               ret = -ENOENT;
 561 +               goto out_bootconf;
 562 +       }
 563 +
 564 +       /* get images path in uImage.FIT */
 565 +       images = fdt_path_offset(fit, FIT_IMAGES_PATH);
 566 +       if (images < 0) {
 567 +               pr_err("FIT: Cannot find %s node: %d\n", FIT_IMAGES_PATH, images);
 568 +               ret = -EINVAL;
 569 +               goto out_bootconf;
 570 +       }
 571 +
 572 +       /* iterate over images in uImage.FIT */
 573 +       fdt_for_each_subnode(node, fit, images) {
 574 +               image_name = fdt_get_name(fit, node, &image_name_len);
 575 +               image_type = fdt_getprop(fit, node, FIT_TYPE_PROP, &image_type_len);
 576 +               image_offset_be = fdt_getprop(fit, node, FIT_DATA_OFFSET_PROP, NULL);
 577 +               image_pos_be = fdt_getprop(fit, node, FIT_DATA_POSITION_PROP, NULL);
 578 +               image_len_be = fdt_getprop(fit, node, FIT_DATA_SIZE_PROP, NULL);
 579 +
 580 +               if (!image_name || !image_type || !image_len_be ||
 581 +                   !image_name_len || !image_type_len)
 582 +                       continue;
 583 +
 584 +               image_len = be32_to_cpu(*image_len_be);
 585 +               if (!image_len)
 586 +                       continue;
 587 +
 588 +               if (image_offset_be)
 589 +                       image_pos = be32_to_cpu(*image_offset_be) + size;
 590 +               else if (image_pos_be)
 591 +                       image_pos = be32_to_cpu(*image_pos_be);
 592 +               else
 593 +                       continue;
 594 +
 595 +               image_description = fdt_getprop(fit, node, FIT_DESC_PROP,
 596 +                                               &image_description_len);
 597 +
 598 +               pr_info("FIT: %16s sub-image 0x%08x..0x%08x \"%.*s\"%s%.*s%s\n",
 599 +                       image_type, image_pos, image_pos + image_len - 1,
 600 +                       image_name_len, image_name, image_description ? " (" : "",
 601 +                       image_description ? image_description_len : 0,
 602 +                       image_description ?: "", image_description ? ") " : "");
 603 +
 604 +               /* only 'filesystem' images should be mapped as partitions */
 605 +               if (strncmp(image_type, FIT_FILESYSTEM_PROP, image_type_len))
 606 +                       continue;
 607 +
 608 +               /* check if sub-image is part of configured loadables */
 609 +               found = false;
 610 +               loadable = config_loadables;
 611 +               loadables_rem_len = config_loadables_len;
 612 +               for (loadcnt = 0; loadables_rem_len > 1 &&
 613 +                                 loadcnt < MAX_FIT_LOADABLES; ++loadcnt) {
 614 +                       loadable_len =
 615 +                               strnlen(loadable, loadables_rem_len - 1) + 1;
 616 +                       loadables_rem_len -= loadable_len;
 617 +                       if (!strncmp(image_name, loadable, loadable_len)) {
 618 +                               found = true;
 619 +                               break;
 620 +                       }
 621 +                       loadable += loadable_len;
 622 +               }
 623 +               if (!found)
 624 +                       continue;
 625 +
 626 +               if (image_pos % (1 << PAGE_SHIFT)) {
 627 +                       dev_err(dev, "FIT: image %.*s start not aligned to page boundaries, skipping\n",
 628 +                               image_name_len, image_name);
 629 +                       continue;
 630 +               }
 631 +
 632 +               if (image_len % (1 << PAGE_SHIFT)) {
 633 +                       dev_err(dev, "FIT: sub-image %.*s end not aligned to page boundaries, skipping\n",
 634 +                               image_name_len, image_name);
 635 +                       continue;
 636 +               }
 637 +
 638 +               start_sect = image_pos >> SECTOR_SHIFT;
 639 +               nr_sects = image_len >> SECTOR_SHIFT;
 640 +               imgmaxsect = max_t(sector_t, imgmaxsect, start_sect + nr_sects);
 641 +
 642 +               if (start_sect + nr_sects > dsectors) {
 643 +                       dev_err(dev, "FIT: sub-image %.*s disk access beyond EOD\n",
 644 +                               image_name_len, image_name);
 645 +                       continue;
 646 +               }
 647 +
 648 +               if (!slot) {
 649 +                       ret = sysfs_create_link_nowarn(&pdev->dev.kobj, bdev_kobj(bdev), "lower_dev");
 650 +                       if (ret && ret != -EEXIST)
 651 +                               goto out_bootconf;
 652 +
 653 +                       ret = 0;
 654 +               }
 655 +
 656 +               add_fit_subimage_device(bdev, slot++, start_sect, nr_sects, true);
 657 +       }
 658 +
 659 +       if (!found || !slot)
 660 +               goto out_bootconf;
 661 +
 662 +       dev_info(dev, "mapped %u uImage.FIT filesystem sub-image%s as /dev/fit%s%u%s\n",
 663 +                slot, (slot > 1)?"s":"", (slot > 1)?"[0...":"", slot - 1,
 664 +                (slot > 1)?"]":"");
 665 +
 666 +       /* in case uImage.FIT is stored in a partition, map the remaining space */
 667 +       if (!bdev->bd_read_only && bdev_is_partition(bdev) &&
 668 +           (imgmaxsect + MIN_FREE_SECT) < dsectors) {
 669 +               add_fit_subimage_device(bdev, slot++, imgmaxsect,
 670 +                                       dsectors - imgmaxsect, false);
 671 +               dev_info(dev, "mapped remaing space as /dev/fitrw\n");
 672 +       }
 673 +
 674 +out_bootconf:
 675 +       kfree(bootconf);
 676 +       kfree(fit);
 677 +out_blkdev:
 678 +       if (!found || ret)
 679 +               blkdev_put(bdev, &_fitblk_claim_ptr);
 680 +
 681 +       return ret;
 682 +}
 683 +
 684 +static int fitblk_match_of_node(struct device *dev, const void *np)
 685 +{
 686 +       int ret;
 687 +
 688 +       ret = device_match_of_node(dev, np);
 689 +       if (ret)
 690 +               return ret;
 691 +
 692 +       /*
 693 +        * To match ubiblock and mtdblock devices by their parent ubi
 694 +        * or mtd device, also consider block device parent
 695 +        */
 696 +       if (!dev->parent)
 697 +               return 0;
 698 +
 699 +       return device_match_of_node(dev->parent, np);
 700 +}
 701 +
 702 +static int fitblk_probe(struct platform_device *pdev)
 703 +{
 704 +       struct device *dev;
 705 +
 706 +       dev = class_find_device(&block_class, NULL, rootdisk, fitblk_match_of_node);
 707 +       if (!dev)
 708 +               return -EPROBE_DEFER;
 709 +
 710 +       return parse_fit_on_dev(dev);
 711 +}
 712 +
 713 +static struct platform_driver fitblk_driver = {
 714 +       .probe          = fitblk_probe,
 715 +       .driver         = {
 716 +               .name   = "fitblk",
 717 +               .owner   = THIS_MODULE,
 718 +       },
 719 +};
 720 +
 721 +static int __init fitblk_init(void)
 722 +{
 723 +       /* detect U-Boot firmware */
 724 +       ubootver = of_get_property(of_chosen, "u-boot,version", NULL);
 725 +       if (!ubootver)
 726 +               return 0;
 727 +
 728 +       /* parse 'rootdisk' property phandle */
 729 +       rootdisk = of_parse_phandle(of_chosen, "rootdisk", 0);
 730 +       if (!rootdisk)
 731 +               return 0;
 732 +
 733 +       if (platform_driver_register(&fitblk_driver))
 734 +               return -ENODEV;
 735 +
 736 +       refcount_set(&num_devs, 1);
 737 +       pdev = platform_device_register_simple("fitblk", -1, NULL, 0);
 738 +       if (IS_ERR(pdev))
 739 +               return PTR_ERR(pdev);
 740 +
 741 +       return 0;
 742 +}
 743 +device_initcall(fitblk_init);
 744 --- /dev/null
 745 +++ b/include/uapi/linux/fitblk.h
 746 @@ -0,0 +1,10 @@
 747 +/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
 748 +#ifndef _UAPI_LINUX_FITBLK_H
 749 +#define _UAPI_LINUX_FITBLK_H
 750 +
 751 +/*
 752 + * IOCTL commands --- we will commandeer 0x46 ('F')
 753 + */
 754 +#define FITBLK_RELEASE             0x4600
 755 +
 756 +#endif /* _UAPI_LINUX_FITBLK_H */