1 // SPDX-License-Identifier: GPL-2.0-only
10 	const char *uuid;  member
15  * match_dev_by_uuid - callback for finding a partition using its uuid
16  * @dev:	device passed in by the caller
21 static int __init match_dev_by_uuid(struct device *dev, const void *data)  in match_dev_by_uuid()  argument
23 	struct block_device *bdev = dev_to_bdev(dev);  in match_dev_by_uuid()
26 	if (!bdev->bd_meta_info ||  in match_dev_by_uuid()
27 	    strncasecmp(cmp->uuid, bdev->bd_meta_info->uuid, cmp->len))  in match_dev_by_uuid()
33  * devt_from_partuuid - looks up the dev_t of a partition by its UUID
34  * @uuid_str:	char array containing ascii UUID
38  * UUID value in its partition_meta_info struct.  This does not search
42  * extracted and used as an offset from the partition identified by the UUID.
49 	struct device *dev = NULL;  in devt_from_partuuid()  local
53 	cmp.uuid = uuid_str;  in devt_from_partuuid()
63 		cmp.len = slash - uuid_str;  in devt_from_partuuid()
71 	dev = class_find_device(&block_class, NULL, &cmp, &match_dev_by_uuid);  in devt_from_partuuid()
72 	if (!dev)  in devt_from_partuuid()
73 		return -ENODEV;  in devt_from_partuuid()
78 		 * to the partition number found by UUID.  in devt_from_partuuid()
80 		*devt = part_devt(dev_to_disk(dev),  in devt_from_partuuid()
81 				  dev_to_bdev(dev)->bd_partno + offset);  in devt_from_partuuid()
83 		*devt = dev->devt;  in devt_from_partuuid()
86 	put_device(dev);  in devt_from_partuuid()
91 	       "Expected PARTUUID=<valid-uuid-id>[/PARTNROFF=%%d]\n");  in devt_from_partuuid()
92 	return -EINVAL;  in devt_from_partuuid()
96  * match_dev_by_label - callback for finding a partition using its label
97  * @dev:	device passed in by the caller
102 static int __init match_dev_by_label(struct device *dev, const void *data)  in match_dev_by_label()  argument
104 	struct block_device *bdev = dev_to_bdev(dev);  in match_dev_by_label()
107 	if (!bdev->bd_meta_info || strcmp(label, bdev->bd_meta_info->volname))  in match_dev_by_label()
114 	struct device *dev;  in devt_from_partlabel()  local
116 	dev = class_find_device(&block_class, NULL, label, &match_dev_by_label);  in devt_from_partlabel()
117 	if (!dev)  in devt_from_partlabel()
118 		return -ENODEV;  in devt_from_partlabel()
119 	*devt = dev->devt;  in devt_from_partlabel()
120 	put_device(dev);  in devt_from_partlabel()
128 	struct device *dev;  in blk_lookup_devt()  local
131 	while ((dev = class_dev_iter_next(&iter))) {  in blk_lookup_devt()
132 		struct gendisk *disk = dev_to_disk(dev);  in blk_lookup_devt()
134 		if (strcmp(dev_name(dev), name))  in blk_lookup_devt()
137 		if (partno < disk->minors) {  in blk_lookup_devt()
141 			devt = MKDEV(MAJOR(dev->devt),  in blk_lookup_devt()
142 				     MINOR(dev->devt) + partno);  in blk_lookup_devt()
160 		return -EINVAL;  in devt_from_devname()
172 	 * Try non-existent, but valid partition, which may only exist after  in devt_from_devname()
175 	while (p > s && isdigit(p[-1]))  in devt_from_devname()
176 		p--;  in devt_from_devname()
178 		return -ENODEV;  in devt_from_devname()
188 	if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p')  in devt_from_devname()
189 		return -ENODEV;  in devt_from_devname()
190 	p[-1] = '\0';  in devt_from_devname()
194 	return -ENODEV;  in devt_from_devname()
206 			return -EINVAL;  in devt_from_devnum()
210 			return -EINVAL;  in devt_from_devnum()
221  *	3) /dev/<disk_name> represents the device number of disk
222  *	4) /dev/<disk_name><decimal> represents the device number
223  *         of partition - device number of disk plus the partition number
224  *	5) /dev/<disk_name>p<decimal> - same as the above, that form is
226  *	6) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the
228  *	   The UUID may be either an EFI/GPT UUID, or refer to an MSDOS
229  *	   partition using the format SSSSSSSS-PP, where SSSSSSSS is a zero-
230  *	   filled hex representation of the 32-bit "NT disk signature", and PP
231  *	   is a zero-filled hex representation of the 1-based partition number.
232  *	7) PARTUUID=<UUID>/PARTNROFF=<int> to select a partition in relation to
250 	if (strncmp(name, "/dev/", 5) == 0)  in early_lookup_bdev()
260 		snprintf(buf, BDEVT_SIZE, "%-9s", tbuf);  in bdevt_str()
268  * print a full list of all partitions - intended for places where the root
275 	struct device *dev;  in printk_all_partitions()  local
278 	while ((dev = class_dev_iter_next(&iter))) {  in printk_all_partitions()
279 		struct gendisk *disk = dev_to_disk(dev);  in printk_all_partitions()
288 		if (get_capacity(disk) == 0 || (disk->flags & GENHD_FL_HIDDEN))  in printk_all_partitions()
293 		 * hex - the same format as the root= option takes.  in printk_all_partitions()
296 		xa_for_each(&disk->part_tbl, idx, part) {  in printk_all_partitions()
301 			       bdevt_str(part->bd_dev, devt_buf),  in printk_all_partitions()
303 			       part->bd_meta_info ?  in printk_all_partitions()
304 					part->bd_meta_info->uuid : "");  in printk_all_partitions()
307 			else if (dev->parent && dev->parent->driver)  in printk_all_partitions()
309 					dev->parent->driver->name);  in printk_all_partitions()