Add some handy defines for some hardcoded magic numbers related to extended partition handling.

Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com --- disk/part_dos.c | 6 +++--- disk/part_dos.h | 3 +++ 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/disk/part_dos.c b/disk/part_dos.c index ef706fb59c..20d35dc9cd 100644 --- a/disk/part_dos.c +++ b/disk/part_dos.c @@ -42,9 +42,9 @@ static inline unsigned int le32_to_int(unsigned char *le32)

static inline int is_extended(int part_type) { - return (part_type == 0x5 || - part_type == 0xf || - part_type == 0x85); + return (part_type == DOS_PART_TYPE_EXTENDED || + part_type == DOS_PART_TYPE_EXTENDED_LBA || + part_type == DOS_PART_TYPE_EXTENDED_LINUX); }

static int get_bootable(dos_partition_t *p) diff --git a/disk/part_dos.h b/disk/part_dos.h index 434b021ae8..dd909a9317 100644 --- a/disk/part_dos.h +++ b/disk/part_dos.h @@ -15,6 +15,9 @@ #define DOS_PBR_MEDIA_TYPE_OFFSET 0x15 #define DOS_MBR 0 #define DOS_PBR 1 +#define DOS_PART_TYPE_EXTENDED 0x05 +#define DOS_PART_TYPE_EXTENDED_LBA 0x0F +#define DOS_PART_TYPE_EXTENDED_LINUX 0x85

typedef struct dos_partition { unsigned char boot_ind; /* 0x80 - active */

Make functions not used outside this file static.

Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com --- disk/part_dos.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/disk/part_dos.c b/disk/part_dos.c index 3b79b9b1b8..2c4ad0b6ba 100644 --- a/disk/part_dos.c +++ b/disk/part_dos.c @@ -302,13 +302,13 @@ static int part_get_info_extended(struct blk_desc *dev_desc, return -1; }

-void part_print_dos(struct blk_desc *dev_desc) +static void part_print_dos(struct blk_desc *dev_desc) { printf("Part\tStart Sector\tNum Sectors\tUUID\t\tType\n"); print_partition_extended(dev_desc, 0, 0, 1, 0); }

-int part_get_info_dos(struct blk_desc *dev_desc, int part, +static int part_get_info_dos(struct blk_desc *dev_desc, int part, struct disk_partition *info) { return part_get_info_extended(dev_desc, 0, 0, 1, part, info, 0);

Add a 'mbr' command to let user create or verify MBR partition layout based on the provided text description. The partition layout is altearnatively read from 'mbr_parts' environment variable. This can be used in scripts to help system image flashing tools to ensure proper partition layout.

The syntax of the text description of the partition list is similar to the one used by the 'gpt' command. Supported parameters are: name (currently ignored), start (partition start offset in bytes), size (in bytes or '-' to expand it to the whole free area), bootable (boolean flag) and id (MBR partition system ID). If one wants to create more than 4 partitions, an 'Extended' primary partition (with 0x05 ID) has to be explicitely provided as a one of the first 4 entries.

Here is the example how to create a 6 partitions (3 on the 'extended volume'), some of the predefined sizes:

setenv mbr_parts 'name=boot,start=4M,size=128M,bootable,id=0x0e;

name=rootfs,size=3072M,id=0x83; name=system-data,size=512M,id=0x83; name=[ext],size=-,id=0x05; name=user,size=-,id=0x83; name=modules,size=100M,id=0x83; name=ramdisk,size=8M,id=0x83'

mbr write mmc 0

Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com --- cmd/Kconfig | 8 ++ cmd/Makefile | 1 + cmd/mbr.c | 314 ++++++++++++++++++++++++++++++++++++++++++++ doc/usage/index.rst | 1 + doc/usage/mbr.rst | 93 +++++++++++++ 5 files changed, 417 insertions(+) create mode 100644 cmd/mbr.c create mode 100644 doc/usage/mbr.rst

diff --git a/cmd/Kconfig b/cmd/Kconfig index 1595de999b..2c3358e359 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -1025,6 +1025,14 @@ config CMD_LSBLK Print list of available block device drivers, and for each, the list of known block devices.

+config CMD_MBR + bool "MBR (Master Boot Record) command" + select DOS_PARTITION + select HAVE_BLOCK_DEVICE + help + Enable the 'mbr' command to ready and write MBR (Master Boot Record) + style partition tables. + config CMD_MISC bool "misc" depends on MISC diff --git a/cmd/Makefile b/cmd/Makefile index dd86675bf2..41379d9a0e 100644 --- a/cmd/Makefile +++ b/cmd/Makefile @@ -178,6 +178,7 @@ obj-$(CONFIG_CMD_ZFS) += zfs.o

obj-$(CONFIG_CMD_DFU) += dfu.o obj-$(CONFIG_CMD_GPT) += gpt.o +obj-$(CONFIG_CMD_MBR) += mbr.o obj-$(CONFIG_CMD_ETHSW) += ethsw.o obj-$(CONFIG_CMD_AXI) += axi.o obj-$(CONFIG_CMD_PVBLOCK) += pvblock.o diff --git a/cmd/mbr.c b/cmd/mbr.c new file mode 100644 index 0000000000..da2e3a4722 --- /dev/null +++ b/cmd/mbr.c @@ -0,0 +1,314 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * cmd_mbr.c -- MBR (Master Boot Record) handling command + * + * Copyright (C) 2020 Samsung Electronics + * author: Marek Szyprowski m.szyprowski@samsung.com + * + * based on the gpt command. + */ + +#include <common.h> +#include <blk.h> +#include <command.h> +#include <malloc.h> +#include <part.h> + +/** + * extract_val() - Extract a value from the key=value pair list + * @str: pointer to string with key=values pairs + * @key: pointer to the key to search for + * + * The list of parameters is come separated, only a value for + * the given key is returend. + * + * Function allocates memory for the value, remember to free! + * + * Return: Pointer to allocated string with the value. + */ +static char *extract_val(const char *str, const char *key) +{ + char *v, *k; + char *s, *strcopy; + char *new = NULL; + + strcopy = strdup(str); + if (strcopy == NULL) + return NULL; + + s = strcopy; + while (s) { + v = strsep(&s, ","); + if (!v) + break; + k = strsep(&v, "="); + if (!k) + break; + if (strcmp(k, key) == 0) { + new = strdup(v); + break; + } + } + + free(strcopy); + + return new; +} + +/** + * found_key() - Search for a key without a value in the parameter list + * @str: pointer to string with key + * @key: pointer to the key to search for + * + * The list of parameters is come separated. + * + * Return: True if key has been found. + */ +static bool found_key(const char *str, const char *key) +{ + char *k; + char *s, *strcopy; + bool result = false; + + strcopy = strdup(str); + if (!strcopy) + return NULL; + + s = strcopy; + while (s) { + k = strsep(&s, ","); + if (!k) + break; + if (strcmp(k, key) == 0) { + result = true; + break; + } + } + + free(strcopy); + + return result; +} + +static int str_to_partitions(const char *str_part, int blksz, + unsigned long *disk_uuid, struct disk_partition **partitions, + int *parts_count) +{ + char *tok, *str, *s; + int i; + char *val, *p; + int p_count; + struct disk_partition *parts; + int errno = 0; + uint64_t size_ll, start_ll; + + if (str_part == NULL) + return -1; + + str = strdup(str_part); + if (str == NULL) + return -ENOMEM; + + /* extract disk guid */ + s = str; + val = extract_val(str, "uuid_disk"); + if (val) { + val = strsep(&val, ";"); + p = val; + *disk_uuid = ustrtoull(p, &p, 0); + free(val); + /* Move s to first partition */ + strsep(&s, ";"); + } + if (s == NULL) { + printf("Error: is the partitions string NULL-terminated?\n"); + return -EINVAL; + } + + /* remove the optional semicolon at the end of the string */ + i = strlen(s) - 1; + if (s[i] == ';') + s[i] = '\0'; + + /* calculate expected number of partitions */ + p_count = 1; + p = s; + while (*p) { + if (*p++ == ';') + p_count++; + } + + /* allocate memory for partitions */ + parts = calloc(sizeof(struct disk_partition), p_count); + if (parts == NULL) + return -ENOMEM; + + /* retrieve partitions data from string */ + for (i = 0; i < p_count; i++) { + tok = strsep(&s, ";"); + + if (tok == NULL) + break; + + /* size */ + val = extract_val(tok, "size"); + if (!val) { /* 'size' is mandatory */ + errno = -4; + goto err; + } + p = val; + if ((strcmp(p, "-") == 0)) { + /* auto extend the size */ + parts[i].size = 0; + } else { + size_ll = ustrtoull(p, &p, 0); + parts[i].size = size_ll / blksz; + } + free(val); + + /* start address */ + val = extract_val(tok, "start"); + if (val) { /* start address is optional */ + p = val; + start_ll = ustrtoull(p, &p, 0); + parts[i].start = start_ll / blksz; + free(val); + } + + /* system id */ + val = extract_val(tok, "id"); + if (!val) { /* '' is mandatory */ + errno = -4; + goto err; + } + p = val; + parts[i].sys_ind = ustrtoul(p, &p, 0); + free(val); + + /* bootable */ + if (found_key(tok, "bootable")) + parts[i].bootable = PART_BOOTABLE; + } + + *parts_count = p_count; + *partitions = parts; + free(str); + + return 0; +err: + free(str); + free(parts); + + return errno; +} + +static int do_write_mbr(struct blk_desc *dev, const char *str) +{ + unsigned long disk_uuid = 0; + struct disk_partition *partitions; + int blksz = dev->blksz; + int count; + + if (str_to_partitions(str, blksz, &disk_uuid, &partitions, &count)) { + printf("MBR: failed to setup partitions from "%s"\n", str); + return -1; + } + + if (layout_mbr_partitions(partitions, count, dev->lba)) { + printf("MBR: failed to layout partitions on the device\n"); + free(partitions); + return -1; + } + + if (write_mbr_partitions(dev, partitions, count, disk_uuid)) { + printf("MBR: failed to write partitions to the device\n"); + free(partitions); + return -1; + } + + return 0; +} + +static int do_verify_mbr(struct blk_desc *dev, const char *str) +{ + unsigned long disk_uuid = 0; + struct disk_partition *partitions; + int blksz = dev->blksz; + int count, i, ret = 1; + + if (str_to_partitions(str, blksz, &disk_uuid, &partitions, &count)) { + printf("MBR: failed to setup partitions from "%s"\n", str); + return -1; + } + + for (i = 0; i < count; i++) { + struct disk_partition p; + + if (part_get_info(dev, i+1, &p)) + goto fail; + + if ((partitions[i].size && p.size < partitions[i].size) || + (partitions[i].start && p.start < partitions[i].start) || + (p.sys_ind != partitions[i].sys_ind)) + goto fail; + } + ret = 0; +fail: + free(partitions); + return ret; +} + +static int do_mbr(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]) +{ + const char *parts = NULL; + int ret = CMD_RET_SUCCESS; + int dev = 0; + char *ep; + struct blk_desc *blk_dev_desc = NULL; + + if (argc != 4 && argc != 5) + return CMD_RET_USAGE; + + dev = (int)simple_strtoul(argv[3], &ep, 10); + if (!ep || ep[0] != '\0') { + printf("'%s' is not a number\n", argv[3]); + return CMD_RET_USAGE; + } + blk_dev_desc = blk_get_dev(argv[2], dev); + if (!blk_dev_desc) { + printf("%s: %s dev %d NOT available\n", + __func__, argv[2], dev); + return CMD_RET_FAILURE; + } + + if ((strcmp(argv[1], "write") == 0)) { + parts = (argc == 5) ? argv[4] : env_get("mbr_parts"); + printf("MBR: write "); + ret = do_write_mbr(blk_dev_desc, parts); + } else if ((strcmp(argv[1], "verify") == 0)) { + printf("MBR: verify "); + parts = (argc == 5) ? argv[4] : env_get("mbr_parts"); + ret = do_verify_mbr(blk_dev_desc, parts); + } else { + return CMD_RET_USAGE; + } + + if (ret) { + printf("error!\n"); + return CMD_RET_FAILURE; + } + + printf("success!\n"); + return CMD_RET_SUCCESS; +} + +U_BOOT_CMD(mbr, CONFIG_SYS_MAXARGS, 1, do_mbr, + "MBR (Master Boot Record)", + "<command> <interface> <dev> <partitions_list>\n" + " - MBR partition table restoration utility\n" + " Restore or check partition information on a device connected\n" + " to the given block interface\n" + " Example usage:\n" + " mbr write mmc 0 ["${mbr_parts}"]\n" + " mbr verify mmc 0 ["${partitions}"]\n" +); diff --git a/doc/usage/index.rst b/doc/usage/index.rst index fbb2c0481c..5869fba189 100644 --- a/doc/usage/index.rst +++ b/doc/usage/index.rst @@ -14,4 +14,5 @@ Shell commands bootefi bootmenu button + mbr pstore diff --git a/doc/usage/mbr.rst b/doc/usage/mbr.rst new file mode 100644 index 0000000000..ee27b00c75 --- /dev/null +++ b/doc/usage/mbr.rst @@ -0,0 +1,93 @@ +.. SPDX-License-Identifier: GPL-2.0+ + +mbr command +=========== + +Synopsis +-------- + +:: + + mbr verify [interface] [device no] [partition list] + mbr write [interface] [device no] [partition list] + +Description +----------- + +The mbr command lets user to create or verify MBR partition layout +based on the provided text description. The partition layout is +altearnatively read from 'mbr_parts' environment variable. This can be +used in scripts to help system image flashing tools to ensure proper +partition layout. + +The syntax of the text description of the partition list is similar to +the one used by the 'gpt' command. + +Supported partition parameters are: + +* name (currently ignored) +* start (partition start offset in bytes) +* size (in bytes or '-' to expand it to the whole free area) +* bootable (boolean flag) +* id (MBR partition system ID) + +If one wants to create more than 4 partitions, an 'Extended' primary +partition (with 0x05 ID) has to be explicitely provided as a one of the +first 4 entries. + +Here is the example how to create a 6 partitions (3 on the 'extended +volume'), some of the predefined sizes: + +:: + + => setenv mbr_parts 'name=boot,start=4M,size=128M,bootable,id=0x0e; + name=rootfs,size=3072M,id=0x83; + name=system-data,size=512M,id=0x83; + name=[ext],size=-,id=0x05; + name=user,size=-,id=0x83; + name=modules,size=100M,id=0x83; + name=ramdisk,size=8M,id=0x83' + => mbr write mmc 0 + +To check if the layout on the MMC #0 storage device matches the provided +text description one has to issue following command (assuming that +mbr_parts environment variable is set): + +:: + + => mbr verify mmc 0 + +The verify sub-command is especially useful in the system update scripts: + +:: + => if mbr verify mmc 0; then + echo MBR layout needs to be updated + ... + fi + +The 'mbr write' command returns 0 on success write or -1 on failure. + +The 'mbr verify' returns 0 if the layout matches the one on the storage +device or -1 if not. + +Configuration +------------- + +To use the mbr command you must specify CONFIG_CMD_MBR=y. + +Return value +------------ + +The variable *$?* takes the following values + ++---+------------------------------+ +| 0 | mbr write was succesful | ++---+------------------------------+ +| 1 | mbr write failed | ++---+------------------------------+ +| 0 | mbr verify was succesful | ++---+------------------------------+ +| 1 | mbr verify was not succesful | ++---+------------------------------+ +|-1 | invalid arguments | ++---+------------------------------+