[U-Boot] [PATCH 4/6] gpt: Support for GPT (GUID Partition Table) restoration

Lukasz Majewski
2012-08-24T08:13:13Z

The restoration of GPT table (both primary and secondary) is now possible.
Simple GUID generation is supported.

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
---
disk/part_efi.c | 225 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
include/part.h | 2 +
2 files changed, 227 insertions(+), 0 deletions(-)

diff --git a/disk/part_efi.c b/disk/part_efi.c
index 86e7f33..c1e8d54 100644
--- a/disk/part_efi.c
+++ b/disk/part_efi.c
@@ -403,4 +403,229 @@ static int is_pte_valid(gpt_entry * pte)
return 1;
}
}
+
+/**
+ * guid_gen(): Generate UUID
+ *
+ * @param dev_desc - block device descriptor
+ *
+ * @return - generated UUID table
+ *
+ * NOTE: The entrophy of this function is small
+ */
+static u8 *guid_gen(block_dev_desc_t * dev_desc)
+{
+ int k = 0;
+ static int i = 1;
+ static u8 __aligned(CONFIG_SYS_CACHELINE_SIZE) guid[16];
+ static u8 __aligned(CONFIG_SYS_CACHELINE_SIZE) ent_pool[512];
+ u32 *ptr = (u32 *) guid;
+
+ /* Entrophy initialization - read random content of one SD sector */
+ if (i == 1) {
+ debug("Init entropy:%x\n", (u32)(dev_desc->lba >> 14));
+
+ if (dev_desc->block_read(dev_desc->dev, (dev_desc->lba >> 14),
+ 1, (u32 *) ent_pool) != 1) {
+ printf("** Can't read from device %d **\n",
+ dev_desc->dev);
+ }
+ }
+
+ for (k = 0; k < 4; k++) {
+ *(ptr + k) = efi_crc32((const void *) ent_pool,
+ sizeof(ent_pool));
+ ent_pool[511 - k] = *(ptr + k);
+ }
+
+ ent_pool[0] = ((u8) i) & 0xff;
+
+ debug("GUID: ");
+ for (k = 0; k < sizeof(guid); k++)
+ debug(" %x ", guid[k]);
+
+ debug(" i:%d,\n", i);
+
+ i++;
+ return guid;
+}
+
+/**
+ * set_protective_mbr(): Set the EFI protective MBR
+ * @param dev_desc - block device descriptor
+ *
+ * @return - zero on success, otherwise error
+ */
+static int set_protective_mbr(block_dev_desc_t *dev_desc)
+{
+ legacy_mbr p_mbr;
+
+ /* Setup the Protective MBR */
+ memset((u32 *) &p_mbr, 0x00, sizeof(p_mbr));
+ /* Append signature */
+ p_mbr.signature = MSDOS_MBR_SIGNATURE;
+ p_mbr.partition_record[0].sys_ind = EFI_PMBR_OSTYPE_EFI_GPT;
+ p_mbr.partition_record[0].start_sect = 1;
+ p_mbr.partition_record[0].nr_sects = (u32) dev_desc->lba;
+
+ /* Write MBR sector to the MMC device */
+ if (dev_desc->block_write(dev_desc->dev, 0, 1, &p_mbr) != 1) {
+ printf("** Can't write to device %d **\n",
+ dev_desc->dev);
+ return -1;
+ }
+
+ return 0;
+}
+
+/**
+ * fill_pte(): Fill the GPT partition table entry
+ *
+ * @param dev_desc - block device descriptor
+ * @param gpt_h - GPT header representation
+ * @param gpt_e - GPT partition table entries
+ * @param parts - number of partitions
+ * @param size - size of each partition
+ * @param name - name of each partition
+ */
+static void fill_pte(block_dev_desc_t *dev_desc, gpt_header *gpt_h,
+ gpt_entry *gpt_e, int parts, unsigned int *size,
+ char *name[])
+{
+ u32 offset = (u32) gpt_h->first_usable_lba;
+ char p[PARTNAME_SZ];
+ int i, k, j;
+ char *s;
+
+ for (i = 0; i < parts; i++) {
+ memcpy(gpt_e[i].partition_type_guid.b,
+ &PARTITION_BASIC_DATA_GUID, 16);
+ memcpy(gpt_e[i].unique_partition_guid.b,
+ guid_gen(dev_desc),
+ sizeof(gpt_e[i].unique_partition_guid.b));
+
+ s = name[i];
+
+ memset(p, 0x00, sizeof(p));
+ for (k = 0, j = 0; k < strlen(s); k++, j += 2) {
+ p[j] = *(s + k);
+ p[j + 1] = '.';
+ }
+
+ memcpy(gpt_e[i].partition_name,
+ p, strlen(p));
+
+ gpt_e[i].starting_lba = cpu_to_le32(offset);
+
+ /* allocate remaining memory in last partition */
+ if (i != parts - 1) {
+ gpt_e[i].ending_lba =
+ cpu_to_le64(offset + size[i] - 1);
+ } else {
+ gpt_e[i].ending_lba = gpt_h->last_usable_lba;
+ }
+
+ memset(&gpt_e[i].attributes, 0,
+ sizeof(gpt_entry_attributes));
+
+ offset += size[i];
+ debug("%s: name: %s offset[%d]: 0x%x size[%d]: 0x%x\n",
+ __func__, name[i], i, offset, i, size[i]);
+ }
+}
+
+/**
+ * set_gpt_table() - Restore the GUID Partition Table
+ *
+ * @param dev_desc - block device descriptor
+ * @param parts - number of partitions
+ * @param size - pointer to array with each partition size
+ * @param name - pointer to array with each partition name
+ *
+ * @return - zero on success, otherwise error
+ */
+int set_gpt_table(block_dev_desc_t *dev_desc,
+ int parts, unsigned int *size, char *name[])
+{
+ const int pte_blk_num = (GPT_ENTRY_NUMBERS * sizeof(gpt_entry)) /
+ dev_desc->blksz;
+ gpt_entry gpt_e[GPT_ENTRY_NUMBERS];
+ gpt_header gpt_h;
+ u32 calc_crc32;
+ u64 val;
+
+ debug("max lba: %x\n", (u32) dev_desc->lba);
+
+ /* Setup the Protective MBR */
+ if (set_protective_mbr(dev_desc) < 0)
+ goto err;
+
+ memset((u32 *) &gpt_h, 0x00, sizeof(gpt_h));
+
+ /* Generate Primary GPT header (LBA1) */
+ gpt_h.signature = cpu_to_le64(GPT_HEADER_SIGNATURE);
+ gpt_h.revision = cpu_to_le32(GPT_HEADER_REVISION_V1);
+ gpt_h.header_size = cpu_to_le32(sizeof(gpt_header));
+ gpt_h.my_lba = cpu_to_le64(1);
+ gpt_h.alternate_lba = cpu_to_le64(dev_desc->lba - 1);
+ gpt_h.first_usable_lba = cpu_to_le64(34);
+ gpt_h.last_usable_lba = cpu_to_le64(dev_desc->lba - 34);
+ gpt_h.partition_entry_lba = cpu_to_le64(2);
+ gpt_h.num_partition_entries = cpu_to_le32(GPT_ENTRY_NUMBERS);
+ gpt_h.sizeof_partition_entry = cpu_to_le32(sizeof(gpt_entry));
+ gpt_h.header_crc32 = 0;
+ gpt_h.partition_entry_array_crc32 = 0;
+ memcpy(gpt_h.disk_guid.b, guid_gen(dev_desc),
+ sizeof(gpt_h.disk_guid.b));
+
+ memset((u32 *) gpt_e, 0x00, sizeof(gpt_e));
+
+ fill_pte(dev_desc, &gpt_h, gpt_e, parts, size, name);
+
+ /* Generate CRC for the Primary GPT Header */
+ calc_crc32 = efi_crc32((const unsigned char *)gpt_e,
+ le32_to_cpu(gpt_h.num_partition_entries) *
+ le32_to_cpu(gpt_h.sizeof_partition_entry));
+ gpt_h.partition_entry_array_crc32 = cpu_to_le32(calc_crc32);
+
+ calc_crc32 = efi_crc32((const unsigned char *)&gpt_h,
+ le32_to_cpu(gpt_h.header_size));
+ gpt_h.header_crc32 = cpu_to_le32(calc_crc32);
+
+ /* Write the First GPT to the block right after the Legacy MBR */
+ if (dev_desc->block_write(dev_desc->dev, 1, 1, &gpt_h) != 1)
+ goto err;
+
+ if (dev_desc->block_write(dev_desc->dev, 2, pte_blk_num, gpt_e)
+ != pte_blk_num)
+ goto err;
+
+ /* recalculate the values for the Second GPT Header*/
+ val = le64_to_cpu(gpt_h.my_lba);
+ gpt_h.my_lba = gpt_h.alternate_lba;
+ gpt_h.alternate_lba = cpu_to_le64(val);
+ gpt_h.header_crc32 = 0;
+
+ calc_crc32 = efi_crc32((const unsigned char *)&gpt_h,
+ le32_to_cpu(gpt_h.header_size));
+ gpt_h.header_crc32 = cpu_to_le32(calc_crc32);
+
+ /* Write the Second GPT that is located at the end of the disk */
+ if (dev_desc->block_write(dev_desc->dev,
+ le32_to_cpu(gpt_h.last_usable_lba + 1),
+ pte_blk_num, gpt_e) != pte_blk_num)
+ goto err;
+
+ if (dev_desc->block_write(dev_desc->dev,
+ le32_to_cpu(gpt_h.my_lba), 1, &gpt_h) != 1)
+ goto err;
+
+ printf("GPT successfully written to block device!\n");
+ return 0;
+
+ err:
+ printf("** Can't write to device %d **\n",
+ dev_desc->dev);
+ return -1;
+}
#endif
diff --git a/include/part.h b/include/part.h
index e1478f4..e12c10f 100644
--- a/include/part.h
+++ b/include/part.h
@@ -161,6 +161,8 @@ int test_part_amiga (block_dev_desc_t *dev_desc);
int get_partition_info_efi (block_dev_desc_t * dev_desc, int part, disk_partition_t *info);
void print_part_efi (block_dev_desc_t *dev_desc);
int test_part_efi (block_dev_desc_t *dev_desc);
+int set_gpt_table(block_dev_desc_t *dev_desc,
+ int parts, unsigned int *blocks, char *name[]);
#endif

#endif /* _PART_H */
--
1.7.2.3