diff options
| -rw-r--r-- | common/Kconfig | 18 | ||||
| -rw-r--r-- | common/Makefile | 2 | ||||
| -rw-r--r-- | common/partitions.c | 200 | ||||
| -rw-r--r-- | include/disks.h | 2 |
4 files changed, 222 insertions, 0 deletions
diff --git a/common/Kconfig b/common/Kconfig index 8e96920e48..1318e7d747 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -406,6 +406,24 @@ config PARTITION bool prompt "Enable Partitions" +if PARTITION + +config PARTITION_DISK + bool "DISK partition support" + help + Add support for handling common partition tables on all kind of disk + like devices (harddisks, CF cards, SD cards and so on) + +if PARTITION_DISK + +config PARTITION_DISK_DOS + bool "DOS partition support" + help + Add support to handle partitions in DOS style. + +endif +endif + config DEFAULT_ENVIRONMENT bool default y diff --git a/common/Makefile b/common/Makefile index 7bb8ea4322..3edf38f3ba 100644 --- a/common/Makefile +++ b/common/Makefile @@ -7,6 +7,8 @@ obj-$(CONFIG_ENV_HANDLING) += environment.o obj-$(CONFIG_AUTO_COMPLETE) += complete.o obj-$(CONFIG_POLLER) += poller.o obj-$(CONFIG_BLOCK) += block.o +obj-$(CONFIG_PARTITION_DISK) += partitions.o + obj-$(CONFIG_CMD_LOADS) += s_record.o obj-$(CONFIG_OFTREE) += oftree.o diff --git a/common/partitions.c b/common/partitions.c new file mode 100644 index 0000000000..e4f3ad69e3 --- /dev/null +++ b/common/partitions.c @@ -0,0 +1,200 @@ +/* + * Copyright (C) 2009...2011 Juergen Beisert, Pengutronix + * + * 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 + * + */ + +/** + * @file + * @brief Generic support for partition tables on disk like media + * + * @todo Support for disks larger than 4 GiB + * @todo Reliable size detection for BIOS based disks (on x86 only) + */ +#include <common.h> +#include <malloc.h> +#include <errno.h> +#include <block.h> +#include <asm/unaligned.h> +#include <disks.h> + +struct partition { + uint64_t first_sec; + uint64_t size; +}; + +struct partition_desc { + int used_entries; + struct partition parts[8]; +}; + +/** + * Reject values which cannot be used in Barebox + * @param val Value to be check + * @return 0 if value can be used in Barebox, -EINVAL if not + * + * @note this routine can be removed when Barebox uses file offsets larger + * than 32 bit + */ +static int check_offset_value(uint64_t val) +{ +#if 1 /* until Barebox can handle 64 bit offsets */ + if (val > (__INT_MAX__ / SECTOR_SIZE)) + return -EINVAL; +#endif + return 0; +} + +/** + * Guess the size of the disk, based on the partition table entries + * @param dev device to create partitions for + * @param table partition table + * @return sector count + */ +static int disk_guess_size(struct device_d *dev, struct partition_entry *table) +{ + uint64_t size = 0; + int i; + + for (i = 0; i < 4; i++) { + if (table[i].partition_start != 0) { + size += get_unaligned(&table[i].partition_start) - size; + size += get_unaligned(&table[i].partition_size); + } + } + /* limit disk sector counts we can't handle due to 32 bit limits */ + if (check_offset_value(size) != 0) { + dev_warn(dev, "Warning: Sector count limited due to 31 bit" + "contraints\n"); + size = __INT_MAX__ / SECTOR_SIZE; + } + + return (int)size; +} + +/** + * Check if a DOS like partition describes this block device + * @param blk Block device to register to + * @param pd Where to store the partition information + * + * It seems at least on ARM this routine canot use temp. stack space for the + * sector. So, keep the malloc/free. + */ +static void __maybe_unused try_dos_partition(struct block_device *blk, + struct partition_desc *pd) +{ + uint8_t *buffer; + struct partition_entry *table; + struct partition pentry; + int i, rc; + + buffer = xmalloc(SECTOR_SIZE); + + /* read in the MBR to get the partition table */ + rc = blk->ops->read(blk, buffer, 0, 1); + if (rc != 0) { + dev_err(blk->dev, "Cannot read MBR/partition table\n"); + goto on_error; + } + + if ((buffer[510] != 0x55) || (buffer[511] != 0xAA)) { + dev_info(blk->dev, "No partition table found\n"); + goto on_error; + } + + table = (struct partition_entry *)&buffer[446]; + + /* valid for x86 BIOS based disks only */ + if (blk->num_blocks == 0) + blk->num_blocks = disk_guess_size(blk->dev, table); + + for (i = 0; i < 4; i++) { + pentry.first_sec = get_unaligned(&table[i].partition_start); + pentry.size = get_unaligned(&table[i].partition_size); + + /* do we have to ignore this partition due to limitations? */ + if (check_offset_value(pentry.first_sec) != 0) + continue; + if (check_offset_value(pentry.size) != 0) + continue; + + if (pentry.first_sec != 0) { + pd->parts[pd->used_entries].first_sec = pentry.first_sec; + pd->parts[pd->used_entries].size = pentry.size; + pd->used_entries++; + } else { + dev_dbg(blk->dev, "Skipping empty partition %d\n", i); + } + } + +on_error: + free(buffer); +} + +/** + * Register one partition on the given block device + * @param blk Block device to register to + * @param part Partition description + * @param no Partition number + * @return 0 on success + */ +static int register_one_partition(struct block_device *blk, + struct partition *part, int no) +{ + char partition_name[19]; + + sprintf(partition_name, "%s.%d", blk->cdev.name, no); + dev_dbg(blk->dev, "Registering partition %s on drive %s\n", + partition_name, blk->cdev.name); + return devfs_add_partition(blk->cdev.name, + part->first_sec * SECTOR_SIZE, + part->size * SECTOR_SIZE, + DEVFS_PARTITION_FIXED, partition_name); +} + +/** + * Try to collect partition information on the given block device + * @param blk Block device to examine + * @return 0 most of the time, negative value else + * + * It is not a failure if no partition information is found + */ +int parse_partition_table(struct block_device *blk) +{ + struct partition_desc pdesc = { .used_entries = 0, }; + int i; + int rc = 0; + +#ifdef CONFIG_PARTITION_DISK_DOS + try_dos_partition(blk, &pdesc); +#endif + if (!pdesc.used_entries) + return 0; + + /* at least one partition description found */ + for (i = 0; i < pdesc.used_entries; i++) { + rc = register_one_partition(blk, &pdesc.parts[i], i); + if (rc != 0) + dev_err(blk->dev, + "Failed to register partition %d on %s (%d)\n", + i, blk->cdev.name, rc); + if (rc != -ENODEV) + rc = 0; + } + + return rc; +} diff --git a/include/disks.h b/include/disks.h index ec136d4ee4..9932750a24 100644 --- a/include/disks.h +++ b/include/disks.h @@ -36,4 +36,6 @@ struct partition_entry { uint32_t partition_size; /*! Start of the partition in LBA notation */ } __attribute__ ((packed)); +extern int parse_partition_table(struct block_device*); + #endif /* DISKS_H */ |