alison@peloton-tech.com wrote:
From: Alison Chaiken alison@she-devel.com
This patch provides support in u-boot for renaming GPT partitions. The renaming is accomplished via a new 'gpt flip' command which is enabled via a CONFIG_CMD_GPT_FLIP option.
The concept for the bootloader state machine is the following:
-- u-boot renames ‘primary’ partitions as ‘candidate’ and tries to boot them. -- Linux, at boot, will rename ‘candidate’ partitions as ‘primary’. -- If u-boot sees a ‘candidate’ partition after a boot attempt, it renames it failed’ and renames the ‘backup’ partition as ‘candidate’.
Logic: -- Partitions can go to ‘failed’ only from ‘candidate’ and only via u-boot. Partitions can go to ‘backup’ only from ‘primary’ and vice-versa, only via Linux. Partitions go to ‘candidate’ from ‘primary’ or ‘backup’ only via u-boot. Only system update software will rename 'failed' partitions.
Rewriting the partition table has the side-effect that all partitions end up with "msftdata" flag set. The reason is that partition type PARTITION_BASIC_DATA_GUID is hard-coded in the gpt_fill_pte() function. This does not appear to cause any harm.
Signed-off-by: Alison Chaiken alison@peloton-tech.com
cmd/Kconfig | 7 ++ cmd/gpt.c | 199 +++++++++++++++++++++++++++++++++++++++++++++++++++++++-- doc/README.gpt | 13 ++++ 3 files changed, 215 insertions(+), 4 deletions(-)
diff --git a/cmd/Kconfig b/cmd/Kconfig index 5ee52f6..a8f7716 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -575,6 +575,13 @@ config CMD_GPT Enable the 'gpt' command to ready and write GPT style partition tables.
+config CMD_GPT_FLIP
- bool "GPT flip-partitions command"
- depends on CMD_GPT
- help
Enables the 'gpt' command to write modified GPT partitiontables via the 'gpt flip' command.config CMD_ARMFLASH #depends on FLASH_CFI_DRIVER bool "armflash" diff --git a/cmd/gpt.c b/cmd/gpt.c index c61d2b1..6a0b70f 100644 --- a/cmd/gpt.c +++ b/cmd/gpt.c @@ -20,6 +20,7 @@ #include <div64.h> #include <memalign.h> #include <linux/compat.h> +#include <linux/sizes.h>
static LIST_HEAD(disk_partitions);
@@ -190,16 +191,33 @@ static struct disk_part *allocate_disk_part(disk_partition_t *info, int partnum) return newpart; }
+static void prettyprint_part_size(char *sizestr, unsigned long partsize,
unsigned long blksize)+{
- unsigned long long partbytes;
- unsigned long partmegabytes;
- partbytes = partsize * blksize;
- partmegabytes = lldiv(partbytes, SZ_1M);
- snprintf(sizestr, 16, "%luMiB", partmegabytes);
+}
static void print_gpt_info(void) { struct list_head *pos; struct disk_part *curr;
char partstartstr[16];
char partsizestr[16];
list_for_each(pos, &disk_partitions) { curr = list_entry(pos, struct disk_part, list);
prettyprint_part_size(partstartstr, (unsigned long)curr->gpt_part_info.start,(unsigned long) curr->gpt_part_info.blksz);prettyprint_part_size(partsizestr, (unsigned long)curr->gpt_part_info.size,(unsigned long) curr->gpt_part_info.blksz);printf("Partition %d:\n", curr->partnum);
printf("1st block %x, size %x\n", (unsigned)curr->gpt_part_info.start,(unsigned)curr->gpt_part_info.size);
printf("Start %s, size %s\n", partstartstr, partsizestr);@@ -211,6 +229,85 @@ static void print_gpt_info(void) } }
+#ifdef CONFIG_CMD_GPT_FLIP +static int calc_parts_list_len(int numparts) +{
- /*
* prefatory string:* doc/README.GPT, suggests that* int partlistlen = UUID_STR_LEN + 1 + strlen("partitions=uuid_disk=");* is correct, but extract_val() expects "uuid_disk" first.*/- int partlistlen = UUID_STR_LEN + 1 + strlen("uuid_disk=");
- /* for the comma */
- partlistlen++;
- /* per-partition additions; numparts starts at 1, so this should be correct */
- partlistlen += numparts * (strlen("name=,") + PART_NAME_LEN + 1);
- /* 17 because partstr in create_gpt_partitions_list() is 16 chars */
- partlistlen += numparts * (strlen("start=MiB,") + 17);
- partlistlen += numparts * (strlen("size=MiB,") + 17);
- partlistlen += numparts * (strlen("uuid=;") + UUID_STR_LEN + 1);
- /* for the terminating null */
- partlistlen++;
- debug("Length of partitions_list is %d for %d partitions\n", partlistlen,
numparts);- return partlistlen;
+}
+/*
- create the string that upstream 'gpt write' command will accept as an
- argument
- From doc/README.gpt, Format of partitions layout:
- "partitions=uuid_disk=...;name=u-boot,size=60MiB,uuid=...;
- name=kernel,size=60MiB,uuid=...;"
- The fields 'name' and 'size' are mandatory for every partition.
- The field 'start' is optional. The fields 'uuid' and 'uuid_disk'
- are optional if CONFIG_RANDOM_UUID is enabled.
- */
+static int create_gpt_partitions_list(int numparts, const char *guid, char *partitions_list) +{
- struct list_head *pos;
- struct disk_part *curr;
- char partstr[PART_NAME_LEN + 1];
- if (!partitions_list)
return -1;- /*
* README.gpt specifies starting with "partitions=" like so:* strcpy(partitions_list, "partitions=uuid_disk=");* but that breaks extract_val, which doesn't skip over 'partitions='.*/- strcpy(partitions_list, "uuid_disk=");
- strncat(partitions_list, guid, UUID_STR_LEN + 1);
- strcat(partitions_list, ";");
- list_for_each(pos, &disk_partitions) {
curr = list_entry(pos, struct disk_part, list);strcat(partitions_list, "name=");strncat(partitions_list, (const char *)curr->gpt_part_info.name, PART_NAME_LEN + 1);strcat(partitions_list, ",start=");prettyprint_part_size(partstr, (unsigned long)curr->gpt_part_info.start,(unsigned long) curr->gpt_part_info.blksz);/* one extra byte for NULL */strncat(partitions_list, partstr, PART_NAME_LEN + 1);strcat(partitions_list, ",size=");/* lbaint_t is unsigned long, per include/ide.h */prettyprint_part_size(partstr, (unsigned long)curr->gpt_part_info.size,(unsigned long) curr->gpt_part_info.blksz);strncat(partitions_list, partstr, PART_NAME_LEN + 1);strcat(partitions_list, ",uuid=");strncat(partitions_list, (const char *)curr->gpt_part_info.uuid,UUID_STR_LEN + 1);strcat(partitions_list, ";");- }
- return 0;
+} +#endif
/*
- read partition info into disk_partitions list where
- it can be printed or modified
@@ -222,8 +319,11 @@ static int get_gpt_info(struct blk_desc *dev_desc) disk_partition_t info; struct disk_part *new_disk_part;
- if (disk_partitions.next == NULL)
INIT_LIST_HEAD(&disk_partitions);
/*
* Always re-read partition info from device, in case* it has changed*/INIT_LIST_HEAD(&disk_partitions);
for (p = 1; p <= MAX_SEARCH_PARTITIONS; p++) { ret = part_get_info(dev_desc, p, &info);
@@ -294,6 +394,8 @@ static int set_gpt_info(struct blk_desc *dev_desc, return -1;
str = strdup(str_part);
if (str == NULL)
return -ENOMEM;/* extract disk guid */ s = str;
@@ -523,6 +625,86 @@ static int do_disk_guid(struct blk_desc *dev_desc, char * const namestr) return 0; }
+#ifdef CONFIG_CMD_GPT_FLIP +static int do_flip_gpt_parts(struct blk_desc *dev_desc) +{
- struct list_head *pos;
- struct disk_part *curr;
- disk_partition_t *new_partitions = NULL;
- char disk_guid[UUID_STR_LEN + 1];
- char *partitions_list, *str_disk_guid;
- u8 part_count = 0;
- int partlistlen, ret, numparts = 0;
- ret = get_disk_guid(dev_desc, disk_guid);
- if (ret < 0)
return ret;
This function should return either CMD_RET_FAILURE or CMD_RET_SUCCESS, since the return value is passed on as the exit code of the calling CMD handler function!
- numparts = get_gpt_info(dev_desc);
- if (numparts < 0)
return numparts;
see above.
- printf("Current partition table with %d partitions is:\n", numparts);
- print_gpt_info();
- partlistlen = calc_parts_list_len(numparts);
- partitions_list = (char *)malloc(partlistlen);
- memset(partitions_list, '\0', partlistlen);
- ret = create_gpt_partitions_list(numparts, (const char *) disk_guid,
partitions_list);- if (ret < 0)
return ret;
see above.
- debug("OLD partitions_list is %s with %d chars\n", partitions_list, strlen(partitions_list));
- ret = set_gpt_info(dev_desc, (const char *)partitions_list, &str_disk_guid,
&new_partitions, &part_count);- if (ret < 0)
return ret;
see above.
- list_for_each(pos, &disk_partitions) {
curr = list_entry(pos, struct disk_part, list);if (!strcmp((char *)curr->gpt_part_info.name, "backup_kernel"))strcpy((char *)curr->gpt_part_info.name, "candidate_kernel");if (!strcmp((char *)curr->gpt_part_info.name, "primary_kernel"))strcpy((char *)curr->gpt_part_info.name, "backup_kernel");if (!strcmp((char *)curr->gpt_part_info.name, "backup_rootfs"))strcpy((char *)curr->gpt_part_info.name, "candidate_rootfs");if (!strcmp((char *)curr->gpt_part_info.name, "primary_rootfs"))strcpy((char *)curr->gpt_part_info.name, "backup_rootfs");- }
- ret = create_gpt_partitions_list(numparts, (const char *) disk_guid, partitions_list);
- if (ret < 0)
return ret;
see above.
- debug("NEW partitions_list is %s with %d chars\n", partitions_list, strlen(partitions_list));
- ret = set_gpt_info(dev_desc, (const char *)partitions_list, &str_disk_guid,
&new_partitions, &part_count);- if (ret < 0)
return ret;
see above.
- debug("Writing new partition table\n");
- ret = gpt_restore(dev_desc, disk_guid, new_partitions, numparts);
- if (ret < 0) {
printf("Writing new partition table failed\n");return ret;
see above.
- }
- debug("Reading back new partition table\n");
- numparts = get_gpt_info(dev_desc);
- if (numparts < 0)
return numparts;
see above.
- printf("new partition table with %d partitions is:\n", numparts);
- print_gpt_info();
- del_gpt_info();
- free(partitions_list);
- free(str_disk_guid);
- free(new_partitions);
- return ret;
see above.
+} +#endif
/**
- do_gpt(): Perform GPT operations
@@ -567,6 +749,10 @@ static int do_gpt(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) return do_disk_guid(blk_dev_desc, varname); } else if (strcmp(argv[1], "read") == 0) { return do_get_gpt_info(blk_dev_desc); +#ifdef CONFIG_CMD_GPT_FLIP
- } else if (strcmp(argv[1], "flip") == 0) {
return do_flip_gpt_parts(blk_dev_desc);
Either make do_flip_gpt_part() return CMD_RET_... as indicated above, or check its return value here and convert it to CMD_RET_SUCCESS or CMD_RET_FAILURE.
Also see my comment to your patch 4/6 concerning this code location.
Lothar Waßmann