Re: [PATCH 12/12] commands: add parted

["Ulrich Ölmann" <u.oelmann@pengutronix.de>]

Hi Sascha,

On Mon, Feb 19 2024 at 09:31 +0100, Sascha Hauer <s.hauer@pengutronix.de> wrote:
> This adds a parted command which behaves pretty much like the GNU parted
> program. Unlike other partition manipulation programs parted has a quite
> convenient command line API suitable for scripting. The tool supports
> these commands:
>
> print    - print a partition table
> mklabel  - create a new partition table
> rm       - remove a partition
> mkpart   - create a partition
> unit     - change input/display units
> refresh  - refresh a partition table (barebox specific)
>
> Multiple commands can be given on a single call so that a full partition
> table including partitions can be created with a single command.
> Examples include:
>
> Print a partition table:
>
> $ parted mmc0 print
>
> create a new partition table:
>
> $ parted mmc0 mklabel gpt
>
> create a new partition table and add a partition beginning at offset
> 1MiB ending at offset 128MiB:
>
> $ parted mmc0 mklabel gpt mkpart rootfs ext4 1MiB 128MiB
>
> The same, using KiB as unit and printing the result at the end:
>
> $ parted mmc0 unit KiB mklabel gpt mkpart rootfs ext4 1024 131072 print
>
> The "refresh" command is barebox specific and is useful when for example
> the alternate GPT is missing. This happens when an image is written.
>
> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
> ---
>  commands/Kconfig  |  21 +++
>  commands/Makefile |   2 +-
>  commands/parted.c | 374 ++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 396 insertions(+), 1 deletion(-)
>  create mode 100644 commands/parted.c
>
> diff --git a/commands/Kconfig b/commands/Kconfig
> index a6806f198e..819fb80411 100644
> --- a/commands/Kconfig
> +++ b/commands/Kconfig
> @@ -655,6 +655,27 @@ config CMD_MOUNT
>  		  -o OPTIONS	set file system OPTIONS
>  		  -v		verbose
>  
> +config CMD_PARTED
> +	tristate
> +	depends on PARTITION
> +	select PARTITION_MANIPULATION
> +	prompt "parted"
> +	help
> +	  parted - edit partition tables
> +
> +	  Usage: parted <device> [command [options...]...]
> +
> +	  parted is a partition manipulation program with a behaviour similar to
> +	  GNU Parted
> +
> +	  commands:
> +	         print   print partitions
> +	         mklabel <type>  create a new partition table
> +	         rm <num>        remove a partition
> +	         mkpart <name> <fstype> <start> <end>    create a new partition
> +	         unit <unit>     change display/input units
> +	         refresh refresh a partition table

just a small nitpick that the last line's alignment could be enhanced:

  s/refresh refresh a partition table/refresh         refresh a partition table/

Best regards
Ulrich


> +
>  config CMD_UBI
>  	tristate
>  	default y if MTD_UBI
> diff --git a/commands/Makefile b/commands/Makefile
> index 4924755500..b311410276 100644
> --- a/commands/Makefile
> +++ b/commands/Makefile
> @@ -146,5 +146,5 @@ obj-$(CONFIG_CMD_UBSAN)		+= ubsan.o
>  obj-$(CONFIG_CMD_SELFTEST)	+= selftest.o
>  obj-$(CONFIG_CMD_TUTORIAL)	+= tutorial.o
>  obj-$(CONFIG_CMD_STACKSMASH)	+= stacksmash.o
> -
> +obj-$(CONFIG_CMD_PARTED)	+= parted.o
>  UBSAN_SANITIZE_ubsan.o := y
> diff --git a/commands/parted.c b/commands/parted.c
> new file mode 100644
> index 0000000000..02bb1cff0c
> --- /dev/null
> +++ b/commands/parted.c
> @@ -0,0 +1,374 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +#include <common.h>
> +#include <command.h>
> +#include <block.h>
> +#include <getopt.h>
> +#include <fcntl.h>
> +#include <disks.h>
> +#include <linux/sizes.h>
> +#include <partitions.h>
> +#include <linux/math64.h>
> +
> +static struct partition_desc *gpdesc;
> +static bool table_needs_write;
> +static const char *gunit_str = "KiB";
> +static uint64_t gunit = 1024;
> +
> +struct unit {
> +	const char *str;
> +	uint64_t size;
> +};
> +
> +static struct unit units[] = {
> +	{ .str = "B", .size = 1 },
> +	{ .str = "s", .size = 512 },
> +	{ .str = "KiB", .size = SZ_1K },
> +	{ .str = "MiB", .size = SZ_1M },
> +	{ .str = "GiB", .size = SZ_1G },
> +	{ .str = "TiB", .size = SZ_1T },
> +	{ .str = "KB", .size = 1000ULL },
> +	{ .str = "MB", .size = 1000ULL * 1000 },
> +	{ .str = "GB", .size = 1000ULL * 1000 * 1000 },
> +	{ .str = "TB", .size = 1000ULL * 1000 * 1000 * 1000 },
> +	{ .str = "k", .size = SZ_1K },
> +	{ .str = "K", .size = SZ_1K },
> +	{ .str = "M", .size = SZ_1M },
> +	{ .str = "G", .size = SZ_1G },
> +};
> +
> +static int parted_strtoull(const char *str, uint64_t *val, uint64_t *mult)
> +{
> +	char *end;
> +	int i;
> +
> +	*val = simple_strtoull(str, &end, 0);
> +
> +	if (!*end) {
> +		*mult = 0;
> +		return 0;
> +	}
> +
> +	for (i = 0; i < ARRAY_SIZE(units); i++) {
> +		if (!strcmp(end, units[i].str)) {
> +			*mult = units[i].size;
> +			return 0;
> +		}
> +	}
> +
> +	printf("Error: Cannot read \"%s\" as number\n", str);
> +
> +	return -EINVAL;
> +}
> +
> +static struct partition_desc *pdesc_get(struct block_device *blk)
> +{
> +	if (gpdesc)
> +		return gpdesc;
> +
> +	gpdesc = partition_table_read(blk);
> +	if (!gpdesc) {
> +		printf("Cannot read partition table\n");
> +		return NULL;
> +	}
> +
> +	return gpdesc;
> +}
> +
> +static int do_unit(struct block_device *blk, int argc, char *argv[])
> +{
> +	int i;
> +
> +	if (argc < 2) {
> +		printf("Error: missing unit\n");
> +		return -EINVAL;
> +	}
> +
> +	for (i = 0; i < ARRAY_SIZE(units); i++) {
> +		if (!strcmp(units[i].str, argv[1])) {
> +			gunit_str = units[i].str;
> +			gunit = units[i].size;
> +			return 2;
> +		}
> +	}
> +
> +	printf("invalid unit: %s\n", argv[1]);
> +
> +	return -EINVAL;
> +}
> +
> +static int do_print(struct block_device *blk, int argc, char *argv[])
> +{
> +	struct partition_desc *pdesc;
> +	struct partition *part;
> +
> +	pdesc = pdesc_get(blk);
> +	if (!pdesc) {
> +		printf("Error: Cannot get partition table from %s\n", blk->cdev.name);
> +		return -EINVAL;
> +	}
> +
> +	printf("Disk /dev/%s: %s\n", blk->cdev.name,
> +	       size_human_readable(blk->num_blocks << SECTOR_SHIFT));
> +	printf("Partition Table: %s\n", pdesc->parser->name);
> +
> +	printf("Number      Start           End          Size     Name\n");
> +
> +	list_for_each_entry(part, &pdesc->partitions, list) {
> +		uint64_t start = part->first_sec << SECTOR_SHIFT;
> +		uint64_t size = part->size << SECTOR_SHIFT;
> +		uint64_t end = start + size - SECTOR_SIZE;
> +
> +		printf(" %3d   %10llu%-3s %10llu%-3s %10llu%-3s  %-36s\n",
> +			part->num,
> +			div64_u64(start, gunit), gunit_str,
> +			div64_u64(end, gunit), gunit_str,
> +			div64_u64(size, gunit), gunit_str,
> +			part->name);
> +	}
> +
> +	return 1;
> +}
> +
> +static int do_mkpart(struct block_device *blk, int argc, char *argv[])
> +{
> +	struct partition_desc *pdesc;
> +	uint64_t start, end;
> +	const char *name, *fs_type;
> +	int ret;
> +	uint64_t mult;
> +
> +	if (argc < 5) {
> +		printf("Error: Missing required arguments\n");
> +		return -EINVAL;
> +	}
> +
> +	name = argv[1];
> +	fs_type = argv[2];
> +
> +	ret = parted_strtoull(argv[3], &start, &mult);
> +	if (ret)
> +		return ret;
> +
> +	ret = parted_strtoull(argv[4], &end, &mult);
> +	if (ret)
> +		return ret;
> +
> +	if (!mult)
> +		mult = gunit;
> +
> +	start *= mult;
> +	end *= mult;
> +
> +	/* If not on sector boundaries move start up and end down */
> +	start = ALIGN(start, SECTOR_SIZE);
> +	end = ALIGN_DOWN(end, SECTOR_SIZE);
> +
> +	/* convert to LBA */
> +	start >>= SECTOR_SHIFT;
> +	end >>= SECTOR_SHIFT;
> +
> +	/*
> +	 * When unit is >= KB then substract one sector for user convenience.
> +	 * It allows to start the next partition where the previous ends
> +	 */
> +	if (mult >= 1000)
> +		end -= 1;
> +
> +	pdesc = pdesc_get(blk);
> +	if (!pdesc)
> +		return -EINVAL;
> +
> +	ret = partition_create(pdesc, name, fs_type, start, end);
> +
> +	if (!ret)
> +		table_needs_write = true;
> +
> +	return ret < 0 ? ret : 5;
> +}
> +
> +static int do_rmpart(struct block_device *blk, int argc, char *argv[])
> +{
> +	struct partition_desc *pdesc;
> +	unsigned long num;
> +	int ret;
> +
> +	if (argc < 2) {
> +		printf("Error: Expecting a partition number.\n");
> +		return -EINVAL;
> +	}
> +
> +	ret = kstrtoul(argv[1], 0, &num);
> +	if (ret)
> +		return ret;
> +
> +	pdesc = pdesc_get(blk);
> +	if (!pdesc)
> +		return -EINVAL;
> +
> +	ret = partition_remove(pdesc, num);
> +	if (ret)
> +		return ret;
> +
> +	table_needs_write = true;
> +
> +	return 2;
> +}
> +
> +static int do_mklabel(struct block_device *blk, int argc, char *argv[])
> +{
> +	struct partition_desc *pdesc;
> +
> +	if (argc < 2) {
> +		printf("Error: Expecting a disk label type.\n");
> +		return -EINVAL;
> +	}
> +
> +	pdesc = partition_table_new(blk, argv[1]);
> +	if (IS_ERR(pdesc)) {
> +		printf("Error: Cannot create partition table: %pe\n", pdesc);
> +		return PTR_ERR(pdesc);
> +	}
> +
> +	table_needs_write = true;
> +
> +	if (gpdesc)
> +		partition_table_free(gpdesc);
> +	gpdesc = pdesc;
> +
> +	return 2;
> +}
> +
> +static int do_refresh(struct block_device *blk, int argc, char *argv[])
> +{
> +	struct partition_desc *pdesc;
> +
> +	pdesc = pdesc_get(blk);
> +	if (!pdesc)
> +		return -EINVAL;
> +
> +	table_needs_write = true;
> +
> +	return 1;
> +}
> +
> +struct parted_command {
> +	const char *name;
> +	int (*command)(struct block_device *blk, int argc, char *argv[]);
> +};
> +
> +struct parted_command parted_commands[] = {
> +	{
> +		.name = "mkpart",
> +		.command = do_mkpart,
> +	}, {
> +		.name = "print",
> +		.command = do_print,
> +	}, {
> +		.name = "rm",
> +		.command = do_rmpart,
> +	}, {
> +		.name = "mklabel",
> +		.command = do_mklabel,
> +	}, {
> +		.name = "unit",
> +		.command = do_unit,
> +	}, {
> +		.name = "refresh",
> +		.command = do_refresh,
> +	},
> +};
> +
> +static int parted_run_command(struct block_device *blk, int argc, char *argv[])
> +{
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(parted_commands); i++) {
> +		struct parted_command *cmd = &parted_commands[i];
> +
> +		if (!strcmp(argv[0], cmd->name))
> +			return cmd->command(blk, argc, argv);
> +	}
> +
> +	printf("No such command: %s\n", argv[0]);
> +
> +	return COMMAND_ERROR;
> +}
> +
> +static int do_parted(int argc, char *argv[])
> +{
> +	struct cdev *cdev;
> +	struct block_device *blk;
> +	int ret = 0;
> +
> +	table_needs_write = false;
> +	gpdesc = NULL;
> +
> +	if (argc < 3)
> +		return COMMAND_ERROR_USAGE;
> +
> +	cdev = cdev_open_by_name(argv[1], O_RDWR);
> +	if (!cdev) {
> +		printf("Cannot open %s\n", argv[1]);
> +		return COMMAND_ERROR;
> +	}
> +
> +	blk = cdev_get_block_device(cdev);
> +	if (!blk) {
> +		ret = -EINVAL;
> +		goto err;
> +	}
> +
> +	argc -= 2;
> +	argv += 2;
> +
> +	while (argc) {
> +		debug("---> run command %s\n", argv[0]);
> +		ret = parted_run_command(blk, argc, argv);
> +		if (ret < 0)
> +			break;
> +
> +		argc -= ret;
> +		argv += ret;
> +
> +		ret = 0;
> +	}
> +
> +	if (!ret && gpdesc && table_needs_write)
> +		ret = partition_table_write(gpdesc);
> +
> +err:
> +	if (gpdesc)
> +		partition_table_free(gpdesc);
> +
> +	cdev_close(cdev);
> +
> +	return ret;
> +}
> +
> +BAREBOX_CMD_HELP_START(parted)
> +BAREBOX_CMD_HELP_TEXT("parted is a partition manipulation program with a behaviour similar to")
> +BAREBOX_CMD_HELP_TEXT("GNU Parted")
> +BAREBOX_CMD_HELP_TEXT("")
> +BAREBOX_CMD_HELP_TEXT("commands:")
> +BAREBOX_CMD_HELP_OPT ("print", "print partitions")
> +BAREBOX_CMD_HELP_OPT ("mklabel <type>", "create a new partition table")
> +BAREBOX_CMD_HELP_OPT ("rm <num>", "remove a partition")
> +BAREBOX_CMD_HELP_OPT ("mkpart <name> <fstype> <start> <end>", "create a new partition")
> +BAREBOX_CMD_HELP_OPT ("unit <unit>", "change display/input units")
> +BAREBOX_CMD_HELP_OPT ("refresh", "refresh a partition table")
> +BAREBOX_CMD_HELP_TEXT("")
> +BAREBOX_CMD_HELP_TEXT("<unit> can be one of \"s\" (sectors), \"B\" (bytes), \"kB\", \"MB\", \"GB\", \"TB\",")
> +BAREBOX_CMD_HELP_TEXT("\"KiB\", \"MiB\", \"GiB\" or \"TiB\"")
> +BAREBOX_CMD_HELP_TEXT("<type> must be \"gpt\"")
> +BAREBOX_CMD_HELP_TEXT("<fstype> can be one of  \"ext2\", \"ext3\", \"ext4\", \"fat16\" or \"fat32\"")
> +BAREBOX_CMD_HELP_TEXT("<name> for MBR partition tables can be one of \"primary\", \"extended\" or")
> +BAREBOX_CMD_HELP_TEXT("\"logical\". For GPT this is a name string.")
> +BAREBOX_CMD_HELP_END
> +
> +BAREBOX_CMD_START(parted)
> +	.cmd            = do_parted,
> +	BAREBOX_CMD_DESC("edit partition tables")
> +	BAREBOX_CMD_OPTS("<device> [command [options...]...]")
> +	BAREBOX_CMD_GROUP(CMD_GRP_FILE)
> +	BAREBOX_CMD_HELP(cmd_parted_help)
> +BAREBOX_CMD_END
-- 
Pengutronix e.K.                           | Ulrich Ölmann               |
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