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 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 68 int 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 return 0; 79 80 slot = 1; 81 /* Validate parition offset and size */ 82 for_each_child_of_node(partitions_np, np) { 83 if (validate_of_partition(np, slot)) { 84 of_node_put(np); 85 of_node_put(partitions_np); 86 87 return -1; 88 } 89 90 slot++; 91 } 92 93 slot = 1; 94 for_each_child_of_node(partitions_np, np) { 95 if (slot >= state->limit) { 96 of_node_put(np); 97 break; 98 } 99 100 add_of_partition(state, slot, np); 101 102 slot++; 103 } 104 105 seq_buf_puts(&state->pp_buf, "\n"); 106 107 return 1; 108 } 109