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 9 static 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 35 static void add_of_partition(struct parsed_partitions *state, int slot, 36 struct device_node *np) 37 { 38 struct partition_meta_info *info; 39 char tmp[sizeof(info->volname) + 4]; 40 const char *partname; 41 int len; 42 43 const __be32 *reg = of_get_property(np, "reg", &len); 44 int a_cells = of_n_addr_cells(np); 45 int s_cells = of_n_size_cells(np); 46 47 /* Convert bytes to sector size */ 48 u64 offset = of_read_number(reg, a_cells) / SECTOR_SIZE; 49 u64 size = of_read_number(reg + a_cells, s_cells) / SECTOR_SIZE; 50 51 put_partition(state, slot, offset, size); 52 53 if (of_property_read_bool(np, "read-only")) 54 state->parts[slot].flags |= ADDPART_FLAG_READONLY; 55 56 /* 57 * Follow MTD label logic, search for label property, 58 * fallback to node name if not found. 59 */ 60 info = &state->parts[slot].info; 61 partname = of_get_property(np, "label", &len); 62 if (!partname) 63 partname = of_get_property(np, "name", &len); 64 strscpy(info->volname, partname, sizeof(info->volname)); 65 66 snprintf(tmp, sizeof(tmp), "(%s)", info->volname); 67 strlcat(state->pp_buf, tmp, PAGE_SIZE); 68 } 69 70 int of_partition(struct parsed_partitions *state) 71 { 72 struct device *ddev = disk_to_dev(state->disk); 73 struct device_node *np; 74 int slot; 75 76 struct device_node *partitions_np = of_node_get(ddev->of_node); 77 78 if (!partitions_np || 79 !of_device_is_compatible(partitions_np, "fixed-partitions")) 80 return 0; 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 strlcat(state->pp_buf, "\n", PAGE_SIZE); 108 109 return 1; 110 } 111