diff options
Diffstat (limited to 'super-gpt.c')
| -rw-r--r-- | super-gpt.c | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/super-gpt.c b/super-gpt.c new file mode 100644 index 0000000..a1e9aa9 --- /dev/null +++ b/super-gpt.c @@ -0,0 +1,220 @@ +/* + * mdadm - manage Linux "md" devices aka RAID arrays. + * + * Copyright (C) 2010 Neil Brown <neilb@suse.de> + * + * + * 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 + * + * Author: Neil Brown + * Email: <neil@brown.name> + * + */ + +/* + * 'gpt' is a pseudo metadata type for devices which have a + * GPT partition table. + * + * Obviously arrays cannot be created or assembled for this type. + * It is used to allow a new bare device to have an partition table + * added so the member partitions can then be included in other + * arrays as relevant. + * + * The meaning operations are: + * examine_super, but not brief_examine_super or export_examine + * load_super + * store_super + */ + +#include "mdadm.h" +#include "part.h" + +static void free_gpt(struct supertype *st) +{ + free(st->sb); + st->sb = NULL; +} + +static void examine_gpt(struct supertype *st, char *homehost) +{ + struct GPT *gpt = st->sb + 512; + struct GPT_part_entry *gpe = st->sb + 1024; + unsigned int i; + + printf(" GPT Magic : %llx\n", (unsigned long long)__le64_to_cpu(gpt->magic)); + printf(" GPT Revision : %ld\n", (long)__le32_to_cpu(gpt->revision)); + for (i = 0; i < __le32_to_cpu(gpt->part_cnt); i++) { + printf(" Partition[%02d] : %12llu sectors at %12llu\n", + i, + (unsigned long long)__le64_to_cpu(gpe[i].starting_lba), + (unsigned long long)__le64_to_cpu(gpe[i].ending_lba)- + (unsigned long long)__le64_to_cpu(gpe[i].starting_lba) + +1 + ); + } +} + +static int load_gpt(struct supertype *st, int fd, char *devname) +{ + struct MBR *super; + struct GPT *gpt_head; + int to_read; + unsigned int sector_size; + + free_gpt(st); + + if (posix_memalign((void**)&super, 4096, 32*512) != 0) { + pr_err("could not allocate superblock\n"); + return 1; + } + + if (!get_dev_sector_size(fd, devname, §or_size)) { + free(super); + return 1; + } + + lseek(fd, 0, 0); + if (read(fd, super, sizeof(*super)) != sizeof(*super)) { + no_read: + if (devname) + pr_err("Cannot read partition table on %s\n", + devname); + free(super); + return 1; + } + + if (super->magic != MBR_SIGNATURE_MAGIC || + super->parts[0].part_type != MBR_GPT_PARTITION_TYPE) { + not_found: + if (devname) + pr_err("No partition table found on %s\n", + devname); + free(super); + return 1; + } + /* Set offset to second block (GPT header) */ + lseek(fd, sector_size, SEEK_SET); + /* Seem to have GPT, load the header */ + gpt_head = (struct GPT*)(super+1); + if (read(fd, gpt_head, sizeof(*gpt_head)) != sizeof(*gpt_head)) + goto no_read; + if (gpt_head->magic != GPT_SIGNATURE_MAGIC) + goto not_found; + if (__le32_to_cpu(gpt_head->part_cnt) >= 128) + goto not_found; + + to_read = __le32_to_cpu(gpt_head->part_cnt) * sizeof(struct GPT_part_entry); + to_read = ((to_read+511)/512) * 512; + /* Set offset to third block (GPT entries) */ + lseek(fd, sector_size*2, SEEK_SET); + if (read(fd, gpt_head+1, to_read) != to_read) + goto no_read; + + st->sb = super; + + if (st->ss == NULL) { + st->ss = &gpt; + st->minor_version = 0; + st->max_devs = 1; + st->info = NULL; + } + return 0; +} + +static int store_gpt(struct supertype *st, int fd) +{ + /* FIXME should I save the boot loader */ + /* need to write two copies! */ + /* FIXME allow for blocks != 512 bytes + *etc + */ + struct MBR *super = st->sb; + struct GPT *gpt; + int to_write; + + gpt = (struct GPT*)(super+1); + + to_write = __le32_to_cpu(gpt->part_cnt) * sizeof(struct GPT_part_entry); + to_write = ((to_write+511)/512) * 512; + + lseek(fd, 0, 0); + if (write(fd, st->sb, to_write) != to_write) + return 4; + + fsync(fd); + ioctl(fd, BLKRRPART, 0); + return 0; +} + +static void getinfo_gpt(struct supertype *st, struct mdinfo *info, char *map) +{ + struct GPT *gpt = st->sb + 512; + struct GPT_part_entry *gpe = st->sb + 1024; + unsigned int i; + + memset(&info->array, 0, sizeof(info->array)); + memset(&info->disk, 0, sizeof(info->disk)); + strcpy(info->text_version, "gpt"); + strcpy(info->name, "gpt"); + info->component_size = 0; + + for (i = 0; i < __le32_to_cpu(gpt->part_cnt); i++) { + unsigned long long last = + (unsigned long long)__le64_to_cpu(gpe[i].ending_lba); + if (last > info->component_size) + info->component_size = last; + } +} + +static struct supertype *match_metadata_desc(char *arg) +{ + struct supertype *st = xmalloc(sizeof(*st)); + + if (!st) + return st; + if (strcmp(arg, "gpt") != 0) { + free(st); + return NULL; + } + + st->ss = &gpt; + st->info = NULL; + st->minor_version = 0; + st->max_devs = 1; + st->sb = NULL; + return st; +} + +static int validate_geometry(struct supertype *st, int level, + int layout, int raiddisks, + int *chunk, unsigned long long size, + unsigned long long data_offset, + char *subdev, unsigned long long *freesize, + int consistency_policy, int verbose) +{ + pr_err("gpt metadata cannot be used this way\n"); + return 0; +} + +struct superswitch gpt = { + .examine_super = examine_gpt, + .validate_geometry = validate_geometry, + .match_metadata_desc = match_metadata_desc, + .load_super = load_gpt, + .store_super = store_gpt, + .getinfo_super = getinfo_gpt, + .free_super = free_gpt, + .name = "gpt", +}; |