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111 lines · 2.6 KiB

1// SPDX-License-Identifier: GPL-2.0
2
3#include <linux/blkdev.h>
4#include <linux/major.h>
5#include <linux/of.h>
6#include <linux/string.h>
7#include "check.h"
8
9static int validate_of_partition(struct device_node *np, int slot)
10{
11 u64 offset, size;
12 int len;
13
14 const __be32 *reg = of_get_property(np, "reg", &len);
15 int a_cells = of_n_addr_cells(np);
16 int s_cells = of_n_size_cells(np);
17
18 /* Make sure reg len match the expected addr and size cells */
19 if (len / sizeof(*reg) != a_cells + s_cells)
20 return -EINVAL;
21
22 /* Validate offset conversion from bytes to sectors */
23 offset = of_read_number(reg, a_cells);
24 if (offset % SECTOR_SIZE)
25 return -EINVAL;
26
27 /* Validate size conversion from bytes to sectors */
28 size = of_read_number(reg + a_cells, s_cells);
29 if (!size || size % SECTOR_SIZE)
30 return -EINVAL;
31
32 return 0;
33}
34
35static void add_of_partition(struct parsed_partitions *state, int slot,
36 struct device_node *np)
37{
38 struct partition_meta_info *info;
39 const char *partname;
40 int len;
41
42 const __be32 *reg = of_get_property(np, "reg", &len);
43 int a_cells = of_n_addr_cells(np);
44 int s_cells = of_n_size_cells(np);
45
46 /* Convert bytes to sector size */
47 u64 offset = of_read_number(reg, a_cells) / SECTOR_SIZE;
48 u64 size = of_read_number(reg + a_cells, s_cells) / SECTOR_SIZE;
49
50 put_partition(state, slot, offset, size);
51
52 if (of_property_read_bool(np, "read-only"))
53 state->parts[slot].flags |= ADDPART_FLAG_READONLY;
54
55 /*
56 * Follow MTD label logic, search for label property,
57 * fallback to node name if not found.
58 */
59 info = &state->parts[slot].info;
60 partname = of_get_property(np, "label", &len);
61 if (!partname)
62 partname = of_get_property(np, "name", &len);
63 strscpy(info->volname, partname, sizeof(info->volname));
64
65 seq_buf_printf(&state->pp_buf, "(%s)", info->volname);
66}
67
68int of_partition(struct parsed_partitions *state)
69{
70 struct device *ddev = disk_to_dev(state->disk);
71 struct device_node *np;
72 int slot;
73
74 struct device_node *partitions_np = of_node_get(ddev->of_node);
75
76 if (!partitions_np ||
77 !of_device_is_compatible(partitions_np, "fixed-partitions")) {
78 of_node_put(partitions_np);
79 return 0;
80 }
81
82 slot = 1;
83 /* Validate parition offset and size */
84 for_each_child_of_node(partitions_np, np) {
85 if (validate_of_partition(np, slot)) {
86 of_node_put(np);
87 of_node_put(partitions_np);
88
89 return -1;
90 }
91
92 slot++;
93 }
94
95 slot = 1;
96 for_each_child_of_node(partitions_np, np) {
97 if (slot >= state->limit) {
98 of_node_put(np);
99 break;
100 }
101
102 add_of_partition(state, slot, np);
103
104 slot++;
105 }
106
107 seq_buf_puts(&state->pp_buf, "\n");
108
109 of_node_put(partitions_np);
110 return 1;
111}