[U-Boot] [PATCH v3 6/7] gpt: Support for new "gpt" command

Lukasz Majewski l.majewski at samsung.com
Thu Sep 13 10:10:04 CEST 2012


New command - "gpt" is supported. It restores the GPT partition table.
It looks into the "partitions" environment variable for partitions definition.
It can be enabled at target configuration file with CONFIG_CMD_GPT.
Simple UUID generator has been implemented. It uses the the gd->start_addr_sp
for entrophy pool. Moreover the pool address is used as crc32 seed.

Signed-off-by: Lukasz Majewski <l.majewski at samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park at samsung.com>

---
Changes for v2:
- gpt command now accepts device medium and its number (e.g. gpt mmc 0)
- UUIDs can be passed via u-boot prompt when used with gpt command
- Format of restored GPT has been changed - now key=value pairs are used
  'name="PARTS_CSA",size=8MiB;\ '
  'name="PARTS_BOOTLOADER",size=60MiB; \'
- guid_gen now accepts "pool" pointer and guid pointer
- gd->start_addr_sp is used as a primary source of entrophy
- static buffers definitions have been removed
- remove memsize_to_blocks function with call to standard ustrtoul
- doxygen comments for functions added

Changes for v3:
- Remove unnecessary braces
---
 common/Makefile  |    1 +
 common/cmd_gpt.c |  404 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 405 insertions(+), 0 deletions(-)
 create mode 100644 common/cmd_gpt.c

diff --git a/common/Makefile b/common/Makefile
index 57da76f..39247c5 100644
--- a/common/Makefile
+++ b/common/Makefile
@@ -185,6 +185,7 @@ COBJS-$(CONFIG_MODEM_SUPPORT) += modem.o
 COBJS-$(CONFIG_UPDATE_TFTP) += update.o
 COBJS-$(CONFIG_USB_KEYBOARD) += usb_kbd.o
 COBJS-$(CONFIG_CMD_DFU) += cmd_dfu.o
+COBJS-$(CONFIG_CMD_GPT) += cmd_gpt.o
 endif
 
 ifdef CONFIG_SPL_BUILD
diff --git a/common/cmd_gpt.c b/common/cmd_gpt.c
new file mode 100644
index 0000000..2460573
--- /dev/null
+++ b/common/cmd_gpt.c
@@ -0,0 +1,404 @@
+/*
+ * cmd_gpt.c -- GPT (GUID Partition Table) handling command
+ *
+ * Copyright (C) 2012 Samsung Electronics
+ * author: Lukasz Majewski <l.majewski at samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <common.h>
+#include <malloc.h>
+#include <command.h>
+#include <mmc.h>
+#include <part_efi.h>
+#include <exports.h>
+
+gpt_entry *gpt_e;
+gpt_header *gpt_h;
+DECLARE_GLOBAL_DATA_PTR;
+static unsigned int gpt_parts;
+
+#ifdef DEBUG
+/**
+ * guid_dump(): Dump guid content
+ *
+ * @param guid - pinter to guid
+ * @param i - number of bytes to dump
+ */
+static void guid_dump(u8 *guid, int i)
+{
+	int k;
+
+	debug("GUID: ");
+	for (k = 0; k < i; k++, guid++)
+		debug(" %x ", *guid);
+	debug("\n");
+}
+#else
+static void guid_dump(u8 *guid, int i) {}
+#endif
+
+/**
+ * guid_gen(): Generate UUID
+ *
+ * @param pool - pointer to pseudo random data (e.g. SP)
+ * @param guid - pointer to guid table
+ *
+ * @return - generated UUID table
+ *
+ * NOTE: The entrophy of this function is small
+ */
+static void guid_gen(const u32 *pool, u8 *guid)
+{
+	int k = 0;
+	u32 *ptr = (u32 *) guid;
+
+	debug("%s: pool: 0x%p guid: 0x%p\n", __func__, pool, guid);
+	for (k = 0; k < 4; k++)
+		*(ptr + k) = crc32((u32) pool, (const void *) (pool - k), 512);
+
+	guid_dump(guid, sizeof(efi_guid_t));
+}
+
+/**
+ * convert_uuid(); Convert UUID stored as string to bytes
+ *
+ * @param uuid - UUID represented as string
+ * @param dst - GUID buffer
+ *
+ * @return
+ */
+static int convert_uuid(char *uuid, u8 *dst)
+{
+	efi_guid_t guid;
+	u16 b, c, d;
+	char *t;
+	u64 e;
+	u32 a;
+	u8 *p;
+
+	debug("%s: uuid: %s\n", __func__, uuid);
+	t = strsep(&uuid, "-");
+	a = (u32)simple_strtoul(t, NULL, 16);
+	t = strsep(&uuid, "-");
+	b = (u16)simple_strtoul(t, NULL, 16);
+	t = strsep(&uuid, "-");
+	c = (u16)simple_strtoul(t, NULL, 16);
+	t = strsep(&uuid, "-");
+	d = (u16)simple_strtoul(t, NULL, 16);
+	e = (u64)simple_strtoull(uuid, NULL, 16);
+
+	p = (u8 *) &e;
+	guid = EFI_GUID(a, b, c, d >> 8, d & 0xFF,
+			*(p + 5), *(p + 4), *(p + 3),
+			*(p + 2), *(p + 1) , *p);
+
+	guid_dump(guid.b, sizeof(efi_guid_t));
+	memcpy(dst, guid.b, sizeof(efi_guid_t));
+
+	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 gpt_fill_pte(block_dev_desc_t *dev_desc, gpt_header *gpt_h,
+		     gpt_entry *gpt_e, int parts, unsigned int *size,
+		     char *name[], char *uuid[])
+{
+	u32 offset = (u32) gpt_h->first_usable_lba;
+	u8 guid[sizeof(efi_guid_t)];
+	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);
+
+		if (uuid[i])
+			convert_uuid(uuid[i], gpt_e[i].unique_partition_guid.b);
+		else {
+			guid_gen((((u32 *) gd->start_addr_sp) - i - 1), guid);
+			memcpy(gpt_e[i].unique_partition_guid.b, guid,
+			       sizeof(efi_guid_t));
+
+		}
+		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]);
+	}
+}
+
+/**
+ * extract_val(): Extract value from a key=value pair
+ *
+ * @param p - pointer to string
+ * @param tab - table to store extracted value
+ * @param i - actual tab element to work on
+ *
+ * @return - zero on success; otherwise error
+ */
+static int extract_val(char **p, char *tab[], int i)
+{
+	char *t, *tok = *p;
+
+	t = strsep(&tok, ",");
+	strsep(&t, "=");
+	tab[i] = calloc(strlen(t) + 1, 1);
+	if (tab[i] == NULL) {
+		printf("%s: calloc failed!\n", __func__);
+		return -1;
+	}
+	strcpy(tab[i], t);
+	*p = tok;
+
+	return 0;
+}
+
+/**
+ * extract_uuid(); Extract UUIDs from a string
+ *
+ * @param uuid - string to uuid representation
+ * @param tab - place to store separated items
+ *
+ * @return - zero on success; otherwise error
+ */
+static int extract_uuid(char *uuid, char *tab[])
+{
+	char *tok = uuid;
+	int i;
+
+	for (i = 0; tok && i < (GPT_PARTS_NUM + 1); i++) {
+		if (extract_val(&tok, tab, i)) {
+			for (i--; i >= 0; i--)
+				free(tab[i]);
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+/**
+ * set_gpt_info(): Fill gpt information for GPT header and partition entries
+ *
+ * @param dev_desc - block device descriptor
+ * @param str_uuid - string uuid representation
+ *
+ * @return - zero on success; otherwise error
+ *
+ * NOTE - uuid table is bigger than GPT_PARTS_NUM to support disk UUID
+ *
+ */
+static int set_gpt_info(block_dev_desc_t *dev_desc, char *str_uuid)
+{
+	char *ps[GPT_PARTS_NUM], *name[GPT_PARTS_NUM];
+	char *uuid[GPT_PARTS_NUM + 1]; /* extra space to store disk uuid */
+	u8 guid[sizeof(gpt_h->disk_guid.b)];
+	unsigned int size[GPT_PARTS_NUM];
+	char *tok, *p, *s, *ss;
+	int i, ret;
+
+	debug("%s: MMC lba num: 0x%x %d\n", __func__,
+	      (unsigned int)dev_desc->lba, (unsigned int)dev_desc->lba);
+
+	for (i = 0; i <= GPT_PARTS_NUM; i++)
+		uuid[i] = NULL;
+
+	s = getenv("partitions");
+	if (s == NULL) {
+		printf("%s: \"partitions\" env variable not defined!\n",
+		       __func__);
+		return -1;
+	}
+
+	if (str_uuid)
+		extract_uuid(str_uuid, uuid);
+
+	ss = calloc(strlen(s) + 1, 1);
+	if (ss == NULL) {
+		printf("%s: calloc failed!\n", __func__);
+		return -1;
+	}
+	memcpy(ss, s, strlen(s) + 1);
+
+	for (i = 0, p = ss; i < GPT_PARTS_NUM; i++) {
+		tok = strsep(&p, ";");
+		if (tok == NULL)
+			break;
+
+		if (extract_val(&tok, name, i)) {
+			ret = -1;
+			goto err;
+		}
+
+		if (extract_val(&tok, ps, i)) {
+			ret = -1;
+			free(name[i]);
+			goto err;
+		}
+	}
+
+	gpt_parts = i;
+
+	printf("found %d partitions\n", gpt_parts);
+
+	for (i = 0; i < gpt_parts; i++) {
+		p = ps[i];
+		size[i] = ustrtoul(p, &p, 0);
+		size[i] /= dev_desc->blksz;
+	}
+
+	gpt_h = calloc(sizeof(gpt_header), 1);
+	gpt_e = calloc(sizeof(gpt_entry), GPT_ENTRY_NUMBERS);
+
+	/* 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;
+
+	if (uuid[0])
+		convert_uuid(uuid[0], gpt_h->disk_guid.b);
+	else {
+		guid_gen((u32 *)gd->start_addr_sp, guid);
+		memcpy(gpt_h->disk_guid.b, guid, sizeof(efi_guid_t));
+	}
+	gpt_fill_pte(dev_desc, gpt_h, gpt_e, gpt_parts, size, name, &uuid[1]);
+
+	puts("save the GPT ...\n");
+	ret = set_gpt_table(dev_desc, gpt_h, gpt_e);
+
+	free(gpt_e);
+	free(gpt_h);
+
+	i = gpt_parts;
+ err:
+	for (i--; i >= 0; i--) {
+		free(name[i]);
+		free(ps[i]);
+	}
+
+	free(ss);
+	return ret;
+}
+
+/**
+ * gpt_mmc_default(): Restore default GPT on a MMC device
+ *
+ * @param dev - number of MMC device
+ * @param str_uuid - string representation of UUIDs
+ *
+ * @return zero on success; otherwise error
+ */
+static int gpt_mmc_default(int dev, char *str_uuid)
+{
+	struct mmc *mmc = find_mmc_device(dev);
+
+	if (mmc == NULL) {
+		printf("%s: mmc dev %d NOT available\n", __func__, dev);
+		return CMD_RET_FAILURE;
+	}
+
+	puts("Using default GPT UUID\n");
+	return set_gpt_info(&mmc->block_dev, str_uuid);
+}
+
+/**
+ * do_gpt(): Perform GPT operations
+ *
+ * @param cmdtp - command name
+ * @param flag
+ * @param argc
+ * @param argv
+ *
+ * @return zero on success; otherwise error
+ */
+static int do_gpt(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	int ret = CMD_RET_SUCCESS;
+	char *str_uuid = NULL;
+	int dev = 0;
+
+	if (argc < 3)
+		return CMD_RET_USAGE;
+
+	if (argc == 4) {
+		str_uuid = strdup(argv[3]);
+		if (!str_uuid) {
+			printf("%s: malloc failed!\n", __func__);
+			return CMD_RET_FAILURE;
+		}
+	}
+
+	if (strcmp(argv[1], "mmc") == 0) {
+		dev = (int)simple_strtoul(argv[2], NULL, 10);
+		if (gpt_mmc_default(dev, str_uuid))
+			return CMD_RET_FAILURE;
+	}
+
+	if (argc == 4)
+		free(str_uuid);
+
+	return ret;
+}
+
+U_BOOT_CMD(gpt, CONFIG_SYS_MAXARGS, 1, do_gpt,
+	"GUID Partition Table",
+	"<interface> <dev> [uuid1=, uuid2=, ..., uuidN=]\n"
+	" - GUID partition table restoration\n"
+	" Restore GPT information on a device connected\n"
+	" to interface\n"
+);
-- 
1.7.2.3



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