This fills in the partition manipulation function hooks to add/remove
efi (GPT) partitions and to write a GPT partition table. This depends on
te msdos partition writing support for generating a protective MBR.

Signed-off-by: Sascha Hauer <[email protected]>
---
 common/partitions/Kconfig |   1 +
 common/partitions/efi.c   | 277 ++++++++++++++++++++++++++++++++++++--
 2 files changed, 265 insertions(+), 13 deletions(-)

diff --git a/common/partitions/Kconfig b/common/partitions/Kconfig
index 7f12383082..3bbcceedc1 100644
--- a/common/partitions/Kconfig
+++ b/common/partitions/Kconfig
@@ -19,6 +19,7 @@ config PARTITION_DISK_EFI
        depends on PARTITION_DISK
        select CRC32
        select PRINTF_UUID
+       select PARTITION_DISK_DOS if PARTITION_MANIPULATION
        bool "EFI: GPT partition support"
        help
          Add support to handle partitions in GUID Partition Table style.
diff --git a/common/partitions/efi.c b/common/partitions/efi.c
index 407c1a4d08..67d4978244 100644
--- a/common/partitions/efi.c
+++ b/common/partitions/efi.c
@@ -23,13 +23,14 @@
 #include <partitions.h>
 
 struct efi_partition_desc {
-       struct partition_desc pd; /* must be first */
-       gpt_header gpt;
+       struct partition_desc pd;
+       gpt_header *gpt;
+       gpt_entry *ptes;
 };
 
 struct efi_partition {
-       struct partition part; /* must be first */
-       gpt_entry pte;
+       struct partition part;
+       gpt_entry *pte;
 };
 
 static const int force_gpt = 
IS_ENABLED(CONFIG_PARTITION_DISK_EFI_GPT_NO_FORCE);
@@ -90,6 +91,7 @@ static gpt_entry *alloc_read_gpt_entries(struct block_device 
*blk,
 
        if (!count)
                return NULL;
+
        pte = kzalloc(count, GFP_KERNEL);
        if (!pte)
                return NULL;
@@ -216,7 +218,8 @@ static int is_gpt_valid(struct block_device *blk, u64 lba,
                le32_to_cpu((*gpt)->sizeof_partition_entry));
 
        if (crc != le32_to_cpu((*gpt)->partition_entry_array_crc32)) {
-               dev_dbg(blk->dev, "GUID Partitition Entry Array CRC check 
failed.\n");
+               dev_dbg(blk->dev, "GUID Partitition Entry Array CRC check 
failed: 0x%08x 0x%08x\n",
+                       crc, le32_to_cpu((*gpt)->partition_entry_array_crc32));
                goto fail_ptes;
        }
 
@@ -441,6 +444,19 @@ static void part_set_efi_name(gpt_entry *pte, char *dest)
        dest[i] = 0;
 }
 
+static void part_get_efi_name(gpt_entry *pte, const char *src)
+{
+       int i;
+       int len = strlen(src);
+
+       for (i = 0; i < GPT_PARTNAME_MAX_SIZE ; i++) {
+               if (i <= len)
+                       pte->partition_name[i] = src[i];
+               else
+                       pte->partition_name[i] = 0;
+       }
+}
+
 static struct partition_desc *efi_partition(void *buf, struct block_device 
*blk)
 {
        gpt_header *gpt = NULL;
@@ -468,8 +484,10 @@ static struct partition_desc *efi_partition(void *buf, 
struct block_device *blk)
        }
 
        epd = xzalloc(sizeof(*epd));
-       INIT_LIST_HEAD(&epd->pd.partitions);
-       epd->gpt = *gpt;
+       partition_desc_init(&epd->pd, blk);
+
+       epd->gpt = gpt;
+       epd->ptes = ptes;
 
        for (i = 0; i < nb_part; i++) {
                if (!is_pte_valid(&ptes[i], last_lba(blk))) {
@@ -478,6 +496,7 @@ static struct partition_desc *efi_partition(void *buf, 
struct block_device *blk)
                }
 
                epart = xzalloc(sizeof(*epart));
+               epart->pte = &ptes[i];
                pentry = &epart->part;
                pentry->first_sec = le64_to_cpu(ptes[i].starting_lba);
                pentry->size = le64_to_cpu(ptes[i].ending_lba) - 
pentry->first_sec;
@@ -485,30 +504,262 @@ static struct partition_desc *efi_partition(void *buf, 
struct block_device *blk)
                part_set_efi_name(&ptes[i], pentry->name);
                snprintf(pentry->partuuid, sizeof(pentry->partuuid), "%pUl", 
&ptes[i].unique_partition_guid);
                pentry->typeuuid = ptes[i].partition_type_guid;
-               pentry->num = i;
+               pentry->num = i + 1;
                list_add_tail(&pentry->list, &epd->pd.partitions);
        }
 out:
-       kfree(gpt);
-       kfree(ptes);
 
        return &epd->pd;
 }
 
 static void efi_partition_free(struct partition_desc *pd)
 {
+       struct efi_partition_desc *epd = container_of(pd, struct 
efi_partition_desc, pd);
        struct partition *part, *tmp;
 
-       list_for_each_entry_safe(part, tmp, &pd->partitions, list)
-               free(part);
+       list_for_each_entry_safe(part, tmp, &pd->partitions, list) {
+               struct efi_partition *epart = container_of(part, struct 
efi_partition, part);
+
+               free(epart);
+       }
+
+       free(epd->ptes);
+       free(epd->gpt);
+       free(epd);
+}
+
+static __maybe_unused struct partition_desc *efi_partition_create_table(struct 
block_device *blk)
+{
+       struct efi_partition_desc *epd = xzalloc(sizeof(*epd));
+       gpt_header *gpt;
+
+       partition_desc_init(&epd->pd, blk);
+
+       epd->gpt = xzalloc(512);
+       gpt = epd->gpt;
+
+       gpt->signature = cpu_to_le64(GPT_HEADER_SIGNATURE);
+       gpt->revision = cpu_to_le32(0x100);
+       gpt->header_size = cpu_to_le32(sizeof(*gpt));
+       gpt->my_lba = cpu_to_le64(1);
+       gpt->alternate_lba = cpu_to_le64(last_lba(blk));
+       gpt->first_usable_lba = cpu_to_le64(34);
+       gpt->last_usable_lba = cpu_to_le64(last_lba(blk) - 34);;
+       generate_random_guid((unsigned char *)&gpt->disk_guid);
+       gpt->partition_entry_lba = cpu_to_le64(2);
+       gpt->num_partition_entries = cpu_to_le32(128);
+       gpt->sizeof_partition_entry = cpu_to_le32(sizeof(gpt_entry));
+
+       pr_info("Created new disk label with GUID %pU\n", &gpt->disk_guid);
+
+       epd->ptes = xzalloc(128 * sizeof(gpt_entry));
+
+       return &epd->pd;
+}
+
+static guid_t partition_linux_data_guid = PARTITION_LINUX_DATA_GUID;
+static guid_t partition_basic_data_guid = PARTITION_BASIC_DATA_GUID;
+
+static const guid_t *fs_type_to_guid(const char *fstype)
+{
+       if (!strcmp(fstype, "ext2"))
+               return &partition_linux_data_guid;
+       if (!strcmp(fstype, "ext3"))
+               return &partition_linux_data_guid;
+       if (!strcmp(fstype, "ext4"))
+               return &partition_linux_data_guid;
+       if (!strcmp(fstype, "fat16"))
+               return &partition_basic_data_guid;
+       if (!strcmp(fstype, "fat32"))
+               return &partition_basic_data_guid;
+
+       return NULL;
+}
+
+static __maybe_unused int efi_partition_mkpart(struct partition_desc *pd,
+                                              const char *name, const char 
*fs_type,
+                                              uint64_t start_lba, uint64_t 
end_lba)
+{
+       struct efi_partition_desc *epd = container_of(pd, struct 
efi_partition_desc, pd);
+       struct efi_partition *epart;
+       struct partition *part;
+       gpt_header *gpt = epd->gpt;
+       int num_parts = le32_to_cpu(gpt->num_partition_entries);
+       gpt_entry *pte;
+       int i;
+       const guid_t *guid;
+
+       if (start_lba < 34) {
+               pr_err("invalid start LBA %lld, minimum is 34\n", start_lba);
+               return -EINVAL;
+       }
+
+       if (end_lba >= last_lba(pd->blk) - 33) {
+               pr_err("invalid end LBA %lld, maximum is %lld\n", start_lba,
+                      last_lba(pd->blk) - 33);
+               return -EINVAL;
+       }
+
+       for (i = 0; i < num_parts; i++) {
+               if (!is_pte_valid(&epd->ptes[i], last_lba(pd->blk)))
+                       break;
+       }
+
+       if (i == num_parts) {
+               pr_err("partition table is full\n");
+               return -ENOSPC;
+       }
+
+       guid = fs_type_to_guid(fs_type);
+       if (!guid) {
+               pr_err("Unknown fs type %s\n", fs_type);
+               return -EINVAL;
+       }
+
+       pte = &epd->ptes[i];
+       epart = xzalloc(sizeof(*epart));
+       part = &epart->part;
+
+       part->first_sec = start_lba;
+       part->size = end_lba - start_lba + 1;
+       part->typeuuid = *guid;
+
+       pte->partition_type_guid = *guid;
+       generate_random_guid((unsigned char *)&pte->unique_partition_guid);
+       pte->starting_lba = cpu_to_le64(start_lba);
+       pte->ending_lba = cpu_to_le64(end_lba);
+       part_get_efi_name(pte, name);
+       part_set_efi_name(pte, part->name);
+       part->num = i;
+
+       list_add_tail(&part->list, &pd->partitions);
+
+       return 0;
+}
+
+static __maybe_unused int efi_partition_rmpart(struct partition_desc *pd, 
struct partition *part)
+{
+       struct efi_partition *epart = container_of(part, struct efi_partition, 
part);
+
+       memset(epart->pte, 0, sizeof(*epart->pte));
+
+       list_del(&part->list);
+       free(epart);
+
+       return 0;
+}
+
+static int efi_protective_mbr(struct block_device *blk)
+{
+       struct partition_desc *pdesc;
+       int ret;
+
+       pdesc = partition_table_new(blk, "msdos");
+       if (IS_ERR(pdesc)) {
+               printf("Error: Cannot create partition table: %pe\n", pdesc);
+               return PTR_ERR(pdesc);
+       }
+
+       ret = partition_create(pdesc, "primary", "0xee", 1, last_lba(blk));
+       if (ret) {
+               pr_err("Cannot create partition: %pe\n", ERR_PTR(ret));
+               goto out;
+       }
+
+       ret = partition_table_write(pdesc);
+       if (ret) {
+               pr_err("Cannot write partition: %pe\n", ERR_PTR(ret));
+               goto out;
+       }
+out:
+       partition_table_free(pdesc);
+
+       return ret;
+}
+
+static __maybe_unused int efi_partition_write(struct partition_desc *pd)
+{
+       struct block_device *blk = pd->blk;
+       struct efi_partition_desc *epd = container_of(pd, struct 
efi_partition_desc, pd);
+       gpt_header *gpt = epd->gpt, *altgpt;
+       int ret;
+       uint32_t count;
+       uint64_t from, size;
+
+       if (le32_to_cpu(gpt->num_partition_entries) != 128) {
+               /*
+                * This is not yet properly implemented. At least writing of the
+                * alternative GPT is not correctly implemented for this case as
+                * we can't assume that the partition entries are written at
+                * last_lba() - 32, we would have to calculate that from the 
number
+                * of partition entries.
+                */
+               pr_err("num_partition_entries is != 128. This is not yet 
supported for writing\n");
+               return -EINVAL;
+       }
+
+       count = le32_to_cpu(gpt->num_partition_entries) *
+               le32_to_cpu(gpt->sizeof_partition_entry);
+
+       gpt->my_lba = cpu_to_le64(1);
+       gpt->partition_entry_array_crc32 = cpu_to_le32(efi_crc32(
+                       (const unsigned char *)epd->ptes, count));
+       gpt->header_crc32 = 0;
+       gpt->header_crc32 = cpu_to_le32(efi_crc32((const unsigned char *)gpt,
+                                                 
le32_to_cpu(gpt->header_size)));
+
+       ret = efi_protective_mbr(blk);
+       if (ret)
+               return ret;
+
+       ret = block_write(blk, gpt, 1, 1);
+       if (ret)
+               goto err_block_write;
+
+       from = le64_to_cpu(gpt->partition_entry_lba);
+       size = count / GPT_BLOCK_SIZE;
+
+       ret = block_write(blk, epd->ptes, from, size);
+       if (ret)
+               goto err_block_write;
+
+       altgpt = xmemdup(gpt, SECTOR_SIZE);
+
+       altgpt->alternate_lba = cpu_to_le64(1);
+       altgpt->my_lba = cpu_to_le64(last_lba(blk));
+       altgpt->partition_entry_lba = cpu_to_le64(last_lba(blk) - 32);
+       altgpt->header_crc32 = 0;
+       altgpt->header_crc32 = cpu_to_le32(efi_crc32((const unsigned char 
*)altgpt,
+                                                 
le32_to_cpu(altgpt->header_size)));
+       ret = block_write(blk, altgpt, last_lba(blk), 1);
+
+       free(altgpt);
+
+       if (ret)
+               goto err_block_write;
+       ret = block_write(blk, epd->ptes, last_lba(blk) - 32, 32);
+       if (ret)
+               goto err_block_write;
+
+       return 0;
+
+err_block_write:
+       pr_err("Cannot write to block device: %pe\n", ERR_PTR(ret));
 
-       free(pd);
+       return ret;
 }
 
 static struct partition_parser efi_partition_parser = {
        .parse = efi_partition,
        .partition_free = efi_partition_free,
+#ifdef CONFIG_PARTITION_MANIPULATION
+       .create = efi_partition_create_table,
+       .mkpart = efi_partition_mkpart,
+       .rmpart = efi_partition_rmpart,
+       .write = efi_partition_write,
+#endif
        .type = filetype_gpt,
+       .name = "gpt",
 };
 
 static int efi_partition_init(void)
-- 
2.39.2


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