Add a small block driver which allows exposing filesystem sub-images contained in U-Boot uImage.FIT images as block partitions. The driver is intended for system using the U-Boot bootloader and requires the user to specify the lower block device to be specified as module parameter 'lower_dev'. The initial approach of using a partition parser for this job has been NACK'ed[1], the suggestion was to implement a tiny stackable block driver instead for this job. Here it comes. As discussed previously, the removal-notification part doesn't work at this point as it depends on a future change introducing such notifications[2]. [1]: https://lore.kernel.org/lkml/Y3Xb2YbBP1jr9Q1j@xxxxxxxxxxxxx/ [2]: https://lore.kernel.org/lkml/Y3zCdJr5dKsADsnM@xxxxxxxxxxxxx/ Signed-off-by: Daniel Golle <daniel@xxxxxxxxxxxxxx> --- MAINTAINERS | 6 + drivers/block/Kconfig | 11 + drivers/block/Makefile | 2 + drivers/block/fitblk.c | 493 +++++++++++++++++++++++++++++++++++++++++ 4 files changed, 512 insertions(+) create mode 100644 drivers/block/fitblk.c diff --git a/MAINTAINERS b/MAINTAINERS index 08b67532e374..39402d6d0b9c 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -21184,6 +21184,12 @@ F: Documentation/filesystems/ubifs-authentication.rst F: Documentation/filesystems/ubifs.rst F: fs/ubifs/ +U-BOOT UIMAGE.FIT PARSER +M: Daniel Golle <daniel@xxxxxxxxxxxxxx> +L: linux-block@xxxxxxxxxxxxxxx +S: Maintained +F: drivers/block/fitblk.c + UBLK USERSPACE BLOCK DRIVER M: Ming Lei <ming.lei@xxxxxxxxxx> L: linux-block@xxxxxxxxxxxxxxx diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig index a41145d52de9..f8618bc869b2 100644 --- a/drivers/block/Kconfig +++ b/drivers/block/Kconfig @@ -383,6 +383,17 @@ config VIRTIO_BLK This is the virtual block driver for virtio. It can be used with QEMU based VMMs (like KVM or Xen). Say Y or M. +config UIMAGE_FIT_BLK + bool "uImage.FIT block driver" + help + This is driver allows using filesystems contained in uImage.FIT images + by mapping them as block devices. + + This driver can currently not be built as a module. + + Say Y if you want to mount filesystems sub-images of a uImage.FIT + stored in a block device partition, mtdblock or ubiblock device. + config BLK_DEV_RBD tristate "Rados block device (RBD)" depends on INET && BLOCK diff --git a/drivers/block/Makefile b/drivers/block/Makefile index 101612cba303..60ab4fc1442d 100644 --- a/drivers/block/Makefile +++ b/drivers/block/Makefile @@ -39,4 +39,6 @@ obj-$(CONFIG_BLK_DEV_NULL_BLK) += null_blk/ obj-$(CONFIG_BLK_DEV_UBLK) += ublk_drv.o +obj-$(CONFIG_UIMAGE_FIT_BLK) += fitblk.o + swim_mod-y := swim.o swim_asm.o diff --git a/drivers/block/fitblk.c b/drivers/block/fitblk.c new file mode 100644 index 000000000000..addb30c44a80 --- /dev/null +++ b/drivers/block/fitblk.c @@ -0,0 +1,493 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * uImage.FIT virtual block device driver. + * + * Copyright (C) 2022 Daniel Golle + * Copyright (C) 2007 Nick Piggin + * Copyright (C) 2007 Novell Inc. + * + * Derived from drivers/block/brd.c which is in parts derived from + * drivers/block/rd.c, and drivers/block/loop.c, copyright of their respective + * owners. + * + * uImage.FIT headers extracted from U-Boot mkimage sources + * (C) Copyright 2008 Semihalf + * (C) Copyright 2000-2005 + * Wolfgang Denk, DENX Software Engineering, wd@xxxxxxx. + */ + +#include <linux/init.h> +#include <linux/initrd.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/major.h> +#include <linux/blkdev.h> +#include <linux/blk-mq.h> +#include <linux/ctype.h> +#include <linux/hdreg.h> +#include <linux/list.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/of_fdt.h> +#include <linux/pagemap.h> +#include <linux/platform_device.h> +#include <linux/types.h> +#include <linux/libfdt.h> + +#define FIT_IMAGES_PATH "/images" +#define FIT_CONFS_PATH "/configurations" + +/* hash/signature/key node */ +#define FIT_HASH_NODENAME "hash" +#define FIT_ALGO_PROP "algo" +#define FIT_VALUE_PROP "value" +#define FIT_IGNORE_PROP "uboot-ignore" +#define FIT_SIG_NODENAME "signature" +#define FIT_KEY_REQUIRED "required" +#define FIT_KEY_HINT "key-name-hint" + +/* cipher node */ +#define FIT_CIPHER_NODENAME "cipher" +#define FIT_ALGO_PROP "algo" + +/* image node */ +#define FIT_DATA_PROP "data" +#define FIT_DATA_POSITION_PROP "data-position" +#define FIT_DATA_OFFSET_PROP "data-offset" +#define FIT_DATA_SIZE_PROP "data-size" +#define FIT_TIMESTAMP_PROP "timestamp" +#define FIT_DESC_PROP "description" +#define FIT_ARCH_PROP "arch" +#define FIT_TYPE_PROP "type" +#define FIT_OS_PROP "os" +#define FIT_COMP_PROP "compression" +#define FIT_ENTRY_PROP "entry" +#define FIT_LOAD_PROP "load" + +/* configuration node */ +#define FIT_KERNEL_PROP "kernel" +#define FIT_FILESYSTEM_PROP "filesystem" +#define FIT_RAMDISK_PROP "ramdisk" +#define FIT_FDT_PROP "fdt" +#define FIT_LOADABLE_PROP "loadables" +#define FIT_DEFAULT_PROP "default" +#define FIT_SETUP_PROP "setup" +#define FIT_FPGA_PROP "fpga" +#define FIT_FIRMWARE_PROP "firmware" +#define FIT_STANDALONE_PROP "standalone" + +#define MIN_FREE_SECT 16 +#define MAX_FIT_LOADABLES 16 + +static char *lower_dev; +static const char *ubootver; +static LIST_HEAD(fitblk_devices); +static DEFINE_MUTEX(devices_mutex); + +module_param(lower_dev, charp, 0444); +MODULE_PARM_DESC(lower_dev, "virtual block device mapping uImage.FIT filesystem images"); + +struct fitblk { + struct gendisk *lower_disk; + sector_t start_sect; + struct gendisk *disk; + struct list_head list; +}; + +static void fitblk_submit_bio(struct bio *orig_bio) +{ + struct bio *bio = orig_bio; + struct fitblk *fitblk = bio->bi_bdev->bd_disk->private_data; + + /* mangle bio and re-submit */ + while (bio) { + bio->bi_iter.bi_sector += fitblk->start_sect; + bio->bi_bdev = fitblk->lower_disk->part0; + bio = bio->bi_next; + } + submit_bio(orig_bio); +} + +static const struct block_device_operations fitblk_fops = { + .owner = THIS_MODULE, + .submit_bio = fitblk_submit_bio, +}; + +static void remove_all_subimages(struct device *dev) +{ + struct list_head *n, *tmp; + struct fitblk *fitblk; + + pr_err("FIT: removing affected devices\n"); + + mutex_lock(&devices_mutex); + list_for_each_safe (n, tmp, &fitblk_devices) { + fitblk = list_entry(n, struct fitblk, list); + if (disk_to_dev(fitblk->lower_disk) != dev) + continue; + + del_gendisk(fitblk->disk); + kfree(fitblk); + } + mutex_unlock(&devices_mutex); +} + +static int fitblk_notify(struct notifier_block *nb, unsigned long action, + void *data) +{ + struct device *dev = data; + + pr_err("FIT: got notification\n"); + + switch (action) { + case BUS_NOTIFY_DEL_DEVICE: + remove_all_subimages(dev); + break; + } + return 0; +}; + +static struct notifier_block fitblk_nb = { + .notifier_call = fitblk_notify, +}; + + +static int add_fit_subimage_device(struct gendisk *lower_disk, unsigned int slot, + sector_t start_sect, sector_t nr_sect, + bool readonly) +{ + struct fitblk *fitblk; + struct gendisk *disk; + int err; + + mutex_lock(&devices_mutex); + + fitblk = kzalloc(sizeof(struct fitblk), GFP_KERNEL); + if (!fitblk) { + err = -ENOMEM; + goto out_unlock; + } + + fitblk->lower_disk = lower_disk; + fitblk->start_sect = start_sect; + + disk = blk_alloc_disk(NUMA_NO_NODE); + if (!disk) { + err = -ENOMEM; + goto out_free_fitblk; + } + + fitblk->disk = disk; + disk->first_minor = 0; + disk->flags = lower_disk->flags | GENHD_FL_NO_PART; + disk->fops = &fitblk_fops; + disk->private_data = fitblk; + if (readonly) { + set_disk_ro(disk, 1); + snprintf(disk->disk_name, sizeof(disk->disk_name), "fit%u", slot); + } else { + strcpy(disk->disk_name, "fitrw"); + } + + set_capacity(disk, nr_sect); + + disk->queue->queue_flags = lower_disk->queue->queue_flags; + memcpy(&disk->queue->limits, &lower_disk->queue->limits, sizeof(struct queue_limits)); + + err = device_add_disk(disk_to_dev(lower_disk), disk, NULL); + if (err) + goto out_cleanup_disk; + + list_add_tail(&fitblk->list, &fitblk_devices); + + mutex_unlock(&devices_mutex); + + return 0; + +out_cleanup_disk: + put_disk(disk); +out_free_fitblk: + kfree(fitblk); +out_unlock: + mutex_unlock(&devices_mutex); + return err; +} + +static int parse_fit_on_dev(struct device *dev) +{ + struct block_device *bdev = dev_to_bdev(dev); + struct gendisk *disk = dev_to_disk(dev); + struct address_space *mapping = disk->part0->bd_inode->i_mapping; + struct folio *folio; + void *fit; + u64 dsize, dsectors, imgmaxsect = 0; + u32 size, image_pos, image_len; + const __be32 *image_offset_be, *image_len_be, *image_pos_be; + int ret = 0, node, images, config; + const char *image_name, *image_type, *image_description, + *config_default, *config_description, *config_loadables; + u32 image_name_len, image_type_len, image_description_len, + bootconf_len, config_default_len, config_description_len, + config_loadables_len; + sector_t fit_start_sect = bdev->bd_start_sect, start_sect, nr_sects; + struct device_node *np = NULL; + const char *bootconf; + const char *loadable; + bool found; + int loadables_rem_len, loadable_len; + u16 loadcnt; + bool lower_is_part = !(bdev == disk->part0); + unsigned int slot = 0; + + /* uImage.FIT should be aligned to page boundaries on disk */ + if (fit_start_sect % (1 << (PAGE_SHIFT - SECTOR_SHIFT))) + return -ESPIPE; + + /* map first page */ + folio = read_mapping_folio(mapping, + fit_start_sect >> (PAGE_SHIFT - SECTOR_SHIFT), + NULL); + + if (IS_ERR(folio)) + return PTR_ERR(folio); + + fit = folio_address(folio) + + offset_in_folio(folio, fit_start_sect * SECTOR_SIZE); + + /* uImage.FIT is based on flattened device tree structure */ + if (fdt_check_header(fit)) { + ret = -EINVAL; + goto out_folio; + } + + /* acquire disk size */ + dsectors = bdev_nr_sectors(bdev); + dsize = dsectors << SECTOR_SHIFT; + + /* silently skip non-external-data legacy uImage.FIT */ + size = fdt_totalsize(fit); + if (size > PAGE_SIZE) { + ret = -EOPNOTSUPP; + goto out_folio; + } + + /* abort if FIT structure is larger than disk or partition size */ + if (size >= dsize) { + ret = -EFBIG; + goto out_folio; + } + + /* set boot config node name U-Boot may have added to the device tree */ + np = of_find_node_by_path("/chosen"); + if (np) + bootconf = of_get_property(np, "u-boot,bootconf", &bootconf_len); + else + bootconf = NULL; + + /* find configuration path in uImage.FIT */ + config = fdt_path_offset(fit, FIT_CONFS_PATH); + if (config < 0) { + pr_err("FIT: Cannot find %s node: %d\n", + FIT_CONFS_PATH, config); + ret = -ENOENT; + goto out_folio; + } + + /* get default configuration node name */ + config_default = + fdt_getprop(fit, config, FIT_DEFAULT_PROP, &config_default_len); + + /* make sure we got either default or selected boot config node name */ + if (!config_default && !bootconf) { + pr_err("FIT: Cannot find default configuration\n"); + ret = -ENOENT; + goto out_folio; + } + + /* find selected boot config node, fallback on default config node */ + node = fdt_subnode_offset(fit, config, bootconf ?: config_default); + if (node < 0) { + pr_err("FIT: Cannot find %s node: %d\n", + bootconf ?: config_default, node); + ret = -ENOENT; + goto out_folio; + } + + pr_info("FIT: Detected U-Boot %s\n", ubootver); + + /* get selected configuration data */ + config_description = + fdt_getprop(fit, node, FIT_DESC_PROP, &config_description_len); + config_loadables = fdt_getprop(fit, node, FIT_LOADABLE_PROP, + &config_loadables_len); + + pr_info("FIT: %s configuration: \"%.*s\"%s%.*s%s\n", + bootconf ? "Selected" : "Default", + bootconf ? bootconf_len : config_default_len, + bootconf ?: config_default, + config_description ? " (" : "", + config_description ? config_description_len : 0, + config_description ?: "", + config_description ? ")" : ""); + + if (!config_loadables || !config_loadables_len) { + pr_err("FIT: No loadables configured in \"%s\"\n", + bootconf ?: config_default); + ret = -ENOENT; + goto out_folio; + } + + /* get images path in uImage.FIT */ + images = fdt_path_offset(fit, FIT_IMAGES_PATH); + if (images < 0) { + pr_err("FIT: Cannot find %s node: %d\n", FIT_IMAGES_PATH, images); + ret = -EINVAL; + goto out_folio; + } + + /* register for notifications, so device removal can be tracked */ + if (disk_to_dev(disk)->bus) { + pr_err("FIT: registering notified on bus %s\n", disk_to_dev(disk)->bus->name); + ret = bus_register_notifier(disk_to_dev(disk)->bus, &fitblk_nb); + if (ret) + goto out_folio; + } + + /* iterate over images in uImage.FIT */ + fdt_for_each_subnode(node, fit, images) { + image_name = fdt_get_name(fit, node, &image_name_len); + image_type = fdt_getprop(fit, node, FIT_TYPE_PROP, &image_type_len); + image_offset_be = fdt_getprop(fit, node, FIT_DATA_OFFSET_PROP, NULL); + image_pos_be = fdt_getprop(fit, node, FIT_DATA_POSITION_PROP, NULL); + image_len_be = fdt_getprop(fit, node, FIT_DATA_SIZE_PROP, NULL); + + if (!image_name || !image_type || !image_len_be) + continue; + + image_len = be32_to_cpu(*image_len_be); + if (!image_len) + continue; + + if (image_offset_be) + image_pos = be32_to_cpu(*image_offset_be) + size; + else if (image_pos_be) + image_pos = be32_to_cpu(*image_pos_be); + else + continue; + + image_description = fdt_getprop(fit, node, FIT_DESC_PROP, + &image_description_len); + + pr_info("FIT: %16s sub-image 0x%08x..0x%08x \"%.*s\"%s%.*s%s\n", + image_type, image_pos, image_pos + image_len - 1, + image_name_len, image_name, image_description ? " (" : "", + image_description ? image_description_len : 0, + image_description ?: "", image_description ? ") " : ""); + + /* only 'filesystem' images should be mapped as partitions */ + if (strncmp(image_type, FIT_FILESYSTEM_PROP, image_type_len)) + continue; + + /* check if sub-image is part of configured loadables */ + found = false; + loadable = config_loadables; + loadables_rem_len = config_loadables_len; + for (loadcnt = 0; loadables_rem_len > 1 && + loadcnt < MAX_FIT_LOADABLES; ++loadcnt) { + loadable_len = + strnlen(loadable, loadables_rem_len - 1) + 1; + loadables_rem_len -= loadable_len; + if (!strncmp(image_name, loadable, loadable_len)) { + found = true; + break; + } + loadable += loadable_len; + } + if (!found) + continue; + + if (image_pos % (1 << PAGE_SHIFT)) { + pr_err("FIT: image %.*s start not aligned to page boundaries, skipping\n", + image_name_len, image_name); + continue; + } + + if (image_len % (1 << PAGE_SHIFT)) { + pr_err("FIT: sub-image %.*s end not aligned to page boundaries, skipping\n", + image_name_len, image_name); + continue; + } + + start_sect = image_pos >> SECTOR_SHIFT; + nr_sects = image_len >> SECTOR_SHIFT; + imgmaxsect = max_t(sector_t, imgmaxsect, start_sect + nr_sects); + + if (start_sect + nr_sects > dsectors) { + pr_err("FIT: sub-image %.*s disk access beyond EOD\n", + image_name_len, image_name); + continue; + } + + add_fit_subimage_device(disk, slot++, fit_start_sect + start_sect, + nr_sects, true); + } + + /* in case uImage.FIT is stored in a partition, map the remaining space */ + if (lower_is_part && (imgmaxsect + MIN_FREE_SECT) < dsectors) + add_fit_subimage_device(disk, slot++, fit_start_sect + imgmaxsect, + dsectors - imgmaxsect, false); + +out_folio: + folio_put(folio); + return ret; +} + +static int fitblk_probe(struct platform_device *pdev) +{ + dev_t devt = devt_from_devname(lower_dev); + struct device *dev; + + if (!devt) + return -EPROBE_DEFER; + + dev = class_find_device_by_devt(&block_class, devt); + if (!dev) + return -EPROBE_DEFER; + + return parse_fit_on_dev(dev); +} + +static struct platform_driver fitblk_driver = { + .probe = fitblk_probe, + .driver = { + .name = "fitblk", + .owner = THIS_MODULE, + }, +}; + +static int __init fitblk_init(void) +{ + struct device_node *np; + + if (!lower_dev) + return 0; + + /* detect U-Boot firmware */ + ubootver = NULL; + np = of_find_node_by_path("/chosen"); + if (np) + ubootver = of_get_property(np, "u-boot,version", NULL); + + if (!ubootver) + return 0; + + platform_device_register_simple("fitblk", -1, NULL, 0); + return platform_driver_register(&fitblk_driver); +} +module_init(fitblk_init); + +MODULE_AUTHOR("Daniel Golle"); +MODULE_DESCRIPTION("uImage.FIT virtual block driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:fitblk"); -- 2.39.0
