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-rw-r--r--fs/partitions/msdos.c552
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diff --git a/fs/partitions/msdos.c b/fs/partitions/msdos.c
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--- a/fs/partitions/msdos.c
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-/*
- * fs/partitions/msdos.c
- *
- * Code extracted from drivers/block/genhd.c
- * Copyright (C) 1991-1998 Linus Torvalds
- *
- * Thanks to Branko Lankester, lankeste@fwi.uva.nl, who found a bug
- * in the early extended-partition checks and added DM partitions
- *
- * Support for DiskManager v6.0x added by Mark Lord,
- * with information provided by OnTrack. This now works for linux fdisk
- * and LILO, as well as loadlin and bootln. Note that disks other than
- * /dev/hda *must* have a "DOS" type 0x51 partition in the first slot (hda1).
- *
- * More flexible handling of extended partitions - aeb, 950831
- *
- * Check partition table on IDE disks for common CHS translations
- *
- * Re-organised Feb 1998 Russell King
- */
-#include <linux/msdos_fs.h>
-
-#include "check.h"
-#include "msdos.h"
-#include "efi.h"
-
-/*
- * Many architectures don't like unaligned accesses, while
- * the nr_sects and start_sect partition table entries are
- * at a 2 (mod 4) address.
- */
-#include <asm/unaligned.h>
-
-#define SYS_IND(p) get_unaligned(&p->sys_ind)
-
-static inline sector_t nr_sects(struct partition *p)
-{
- return (sector_t)get_unaligned_le32(&p->nr_sects);
-}
-
-static inline sector_t start_sect(struct partition *p)
-{
- return (sector_t)get_unaligned_le32(&p->start_sect);
-}
-
-static inline int is_extended_partition(struct partition *p)
-{
- return (SYS_IND(p) == DOS_EXTENDED_PARTITION ||
- SYS_IND(p) == WIN98_EXTENDED_PARTITION ||
- SYS_IND(p) == LINUX_EXTENDED_PARTITION);
-}
-
-#define MSDOS_LABEL_MAGIC1 0x55
-#define MSDOS_LABEL_MAGIC2 0xAA
-
-static inline int
-msdos_magic_present(unsigned char *p)
-{
- return (p[0] == MSDOS_LABEL_MAGIC1 && p[1] == MSDOS_LABEL_MAGIC2);
-}
-
-/* Value is EBCDIC 'IBMA' */
-#define AIX_LABEL_MAGIC1 0xC9
-#define AIX_LABEL_MAGIC2 0xC2
-#define AIX_LABEL_MAGIC3 0xD4
-#define AIX_LABEL_MAGIC4 0xC1
-static int aix_magic_present(struct parsed_partitions *state, unsigned char *p)
-{
- struct partition *pt = (struct partition *) (p + 0x1be);
- Sector sect;
- unsigned char *d;
- int slot, ret = 0;
-
- if (!(p[0] == AIX_LABEL_MAGIC1 &&
- p[1] == AIX_LABEL_MAGIC2 &&
- p[2] == AIX_LABEL_MAGIC3 &&
- p[3] == AIX_LABEL_MAGIC4))
- return 0;
- /* Assume the partition table is valid if Linux partitions exists */
- for (slot = 1; slot <= 4; slot++, pt++) {
- if (pt->sys_ind == LINUX_SWAP_PARTITION ||
- pt->sys_ind == LINUX_RAID_PARTITION ||
- pt->sys_ind == LINUX_DATA_PARTITION ||
- pt->sys_ind == LINUX_LVM_PARTITION ||
- is_extended_partition(pt))
- return 0;
- }
- d = read_part_sector(state, 7, &sect);
- if (d) {
- if (d[0] == '_' && d[1] == 'L' && d[2] == 'V' && d[3] == 'M')
- ret = 1;
- put_dev_sector(sect);
- };
- return ret;
-}
-
-/*
- * Create devices for each logical partition in an extended partition.
- * The logical partitions form a linked list, with each entry being
- * a partition table with two entries. The first entry
- * is the real data partition (with a start relative to the partition
- * table start). The second is a pointer to the next logical partition
- * (with a start relative to the entire extended partition).
- * We do not create a Linux partition for the partition tables, but
- * only for the actual data partitions.
- */
-
-static void parse_extended(struct parsed_partitions *state,
- sector_t first_sector, sector_t first_size)
-{
- struct partition *p;
- Sector sect;
- unsigned char *data;
- sector_t this_sector, this_size;
- sector_t sector_size = bdev_logical_block_size(state->bdev) / 512;
- int loopct = 0; /* number of links followed
- without finding a data partition */
- int i;
-
- this_sector = first_sector;
- this_size = first_size;
-
- while (1) {
- if (++loopct > 100)
- return;
- if (state->next == state->limit)
- return;
- data = read_part_sector(state, this_sector, &sect);
- if (!data)
- return;
-
- if (!msdos_magic_present(data + 510))
- goto done;
-
- p = (struct partition *) (data + 0x1be);
-
- /*
- * Usually, the first entry is the real data partition,
- * the 2nd entry is the next extended partition, or empty,
- * and the 3rd and 4th entries are unused.
- * However, DRDOS sometimes has the extended partition as
- * the first entry (when the data partition is empty),
- * and OS/2 seems to use all four entries.
- */
-
- /*
- * First process the data partition(s)
- */
- for (i=0; i<4; i++, p++) {
- sector_t offs, size, next;
- if (!nr_sects(p) || is_extended_partition(p))
- continue;
-
- /* Check the 3rd and 4th entries -
- these sometimes contain random garbage */
- offs = start_sect(p)*sector_size;
- size = nr_sects(p)*sector_size;
- next = this_sector + offs;
- if (i >= 2) {
- if (offs + size > this_size)
- continue;
- if (next < first_sector)
- continue;
- if (next + size > first_sector + first_size)
- continue;
- }
-
- put_partition(state, state->next, next, size);
- if (SYS_IND(p) == LINUX_RAID_PARTITION)
- state->parts[state->next].flags = ADDPART_FLAG_RAID;
- loopct = 0;
- if (++state->next == state->limit)
- goto done;
- }
- /*
- * Next, process the (first) extended partition, if present.
- * (So far, there seems to be no reason to make
- * parse_extended() recursive and allow a tree
- * of extended partitions.)
- * It should be a link to the next logical partition.
- */
- p -= 4;
- for (i=0; i<4; i++, p++)
- if (nr_sects(p) && is_extended_partition(p))
- break;
- if (i == 4)
- goto done; /* nothing left to do */
-
- this_sector = first_sector + start_sect(p) * sector_size;
- this_size = nr_sects(p) * sector_size;
- put_dev_sector(sect);
- }
-done:
- put_dev_sector(sect);
-}
-
-/* james@bpgc.com: Solaris has a nasty indicator: 0x82 which also
- indicates linux swap. Be careful before believing this is Solaris. */
-
-static void parse_solaris_x86(struct parsed_partitions *state,
- sector_t offset, sector_t size, int origin)
-{
-#ifdef CONFIG_SOLARIS_X86_PARTITION
- Sector sect;
- struct solaris_x86_vtoc *v;
- int i;
- short max_nparts;
-
- v = read_part_sector(state, offset + 1, &sect);
- if (!v)
- return;
- if (le32_to_cpu(v->v_sanity) != SOLARIS_X86_VTOC_SANE) {
- put_dev_sector(sect);
- return;
- }
- {
- char tmp[1 + BDEVNAME_SIZE + 10 + 11 + 1];
-
- snprintf(tmp, sizeof(tmp), " %s%d: <solaris:", state->name, origin);
- strlcat(state->pp_buf, tmp, PAGE_SIZE);
- }
- if (le32_to_cpu(v->v_version) != 1) {
- char tmp[64];
-
- snprintf(tmp, sizeof(tmp), " cannot handle version %d vtoc>\n",
- le32_to_cpu(v->v_version));
- strlcat(state->pp_buf, tmp, PAGE_SIZE);
- put_dev_sector(sect);
- return;
- }
- /* Ensure we can handle previous case of VTOC with 8 entries gracefully */
- max_nparts = le16_to_cpu (v->v_nparts) > 8 ? SOLARIS_X86_NUMSLICE : 8;
- for (i=0; i<max_nparts && state->next<state->limit; i++) {
- struct solaris_x86_slice *s = &v->v_slice[i];
- char tmp[3 + 10 + 1 + 1];
-
- if (s->s_size == 0)
- continue;
- snprintf(tmp, sizeof(tmp), " [s%d]", i);
- strlcat(state->pp_buf, tmp, PAGE_SIZE);
- /* solaris partitions are relative to current MS-DOS
- * one; must add the offset of the current partition */
- put_partition(state, state->next++,
- le32_to_cpu(s->s_start)+offset,
- le32_to_cpu(s->s_size));
- }
- put_dev_sector(sect);
- strlcat(state->pp_buf, " >\n", PAGE_SIZE);
-#endif
-}
-
-#if defined(CONFIG_BSD_DISKLABEL)
-/*
- * Create devices for BSD partitions listed in a disklabel, under a
- * dos-like partition. See parse_extended() for more information.
- */
-static void parse_bsd(struct parsed_partitions *state,
- sector_t offset, sector_t size, int origin, char *flavour,
- int max_partitions)
-{
- Sector sect;
- struct bsd_disklabel *l;
- struct bsd_partition *p;
- char tmp[64];
-
- l = read_part_sector(state, offset + 1, &sect);
- if (!l)
- return;
- if (le32_to_cpu(l->d_magic) != BSD_DISKMAGIC) {
- put_dev_sector(sect);
- return;
- }
-
- snprintf(tmp, sizeof(tmp), " %s%d: <%s:", state->name, origin, flavour);
- strlcat(state->pp_buf, tmp, PAGE_SIZE);
-
- if (le16_to_cpu(l->d_npartitions) < max_partitions)
- max_partitions = le16_to_cpu(l->d_npartitions);
- for (p = l->d_partitions; p - l->d_partitions < max_partitions; p++) {
- sector_t bsd_start, bsd_size;
-
- if (state->next == state->limit)
- break;
- if (p->p_fstype == BSD_FS_UNUSED)
- continue;
- bsd_start = le32_to_cpu(p->p_offset);
- bsd_size = le32_to_cpu(p->p_size);
- if (offset == bsd_start && size == bsd_size)
- /* full parent partition, we have it already */
- continue;
- if (offset > bsd_start || offset+size < bsd_start+bsd_size) {
- strlcat(state->pp_buf, "bad subpartition - ignored\n", PAGE_SIZE);
- continue;
- }
- put_partition(state, state->next++, bsd_start, bsd_size);
- }
- put_dev_sector(sect);
- if (le16_to_cpu(l->d_npartitions) > max_partitions) {
- snprintf(tmp, sizeof(tmp), " (ignored %d more)",
- le16_to_cpu(l->d_npartitions) - max_partitions);
- strlcat(state->pp_buf, tmp, PAGE_SIZE);
- }
- strlcat(state->pp_buf, " >\n", PAGE_SIZE);
-}
-#endif
-
-static void parse_freebsd(struct parsed_partitions *state,
- sector_t offset, sector_t size, int origin)
-{
-#ifdef CONFIG_BSD_DISKLABEL
- parse_bsd(state, offset, size, origin, "bsd", BSD_MAXPARTITIONS);
-#endif
-}
-
-static void parse_netbsd(struct parsed_partitions *state,
- sector_t offset, sector_t size, int origin)
-{
-#ifdef CONFIG_BSD_DISKLABEL
- parse_bsd(state, offset, size, origin, "netbsd", BSD_MAXPARTITIONS);
-#endif
-}
-
-static void parse_openbsd(struct parsed_partitions *state,
- sector_t offset, sector_t size, int origin)
-{
-#ifdef CONFIG_BSD_DISKLABEL
- parse_bsd(state, offset, size, origin, "openbsd",
- OPENBSD_MAXPARTITIONS);
-#endif
-}
-
-/*
- * Create devices for Unixware partitions listed in a disklabel, under a
- * dos-like partition. See parse_extended() for more information.
- */
-static void parse_unixware(struct parsed_partitions *state,
- sector_t offset, sector_t size, int origin)
-{
-#ifdef CONFIG_UNIXWARE_DISKLABEL
- Sector sect;
- struct unixware_disklabel *l;
- struct unixware_slice *p;
-
- l = read_part_sector(state, offset + 29, &sect);
- if (!l)
- return;
- if (le32_to_cpu(l->d_magic) != UNIXWARE_DISKMAGIC ||
- le32_to_cpu(l->vtoc.v_magic) != UNIXWARE_DISKMAGIC2) {
- put_dev_sector(sect);
- return;
- }
- {
- char tmp[1 + BDEVNAME_SIZE + 10 + 12 + 1];
-
- snprintf(tmp, sizeof(tmp), " %s%d: <unixware:", state->name, origin);
- strlcat(state->pp_buf, tmp, PAGE_SIZE);
- }
- p = &l->vtoc.v_slice[1];
- /* I omit the 0th slice as it is the same as whole disk. */
- while (p - &l->vtoc.v_slice[0] < UNIXWARE_NUMSLICE) {
- if (state->next == state->limit)
- break;
-
- if (p->s_label != UNIXWARE_FS_UNUSED)
- put_partition(state, state->next++,
- le32_to_cpu(p->start_sect),
- le32_to_cpu(p->nr_sects));
- p++;
- }
- put_dev_sector(sect);
- strlcat(state->pp_buf, " >\n", PAGE_SIZE);
-#endif
-}
-
-/*
- * Minix 2.0.0/2.0.2 subpartition support.
- * Anand Krishnamurthy <anandk@wiproge.med.ge.com>
- * Rajeev V. Pillai <rajeevvp@yahoo.com>
- */
-static void parse_minix(struct parsed_partitions *state,
- sector_t offset, sector_t size, int origin)
-{
-#ifdef CONFIG_MINIX_SUBPARTITION
- Sector sect;
- unsigned char *data;
- struct partition *p;
- int i;
-
- data = read_part_sector(state, offset, &sect);
- if (!data)
- return;
-
- p = (struct partition *)(data + 0x1be);
-
- /* The first sector of a Minix partition can have either
- * a secondary MBR describing its subpartitions, or
- * the normal boot sector. */
- if (msdos_magic_present (data + 510) &&
- SYS_IND(p) == MINIX_PARTITION) { /* subpartition table present */
- char tmp[1 + BDEVNAME_SIZE + 10 + 9 + 1];
-
- snprintf(tmp, sizeof(tmp), " %s%d: <minix:", state->name, origin);
- strlcat(state->pp_buf, tmp, PAGE_SIZE);
- for (i = 0; i < MINIX_NR_SUBPARTITIONS; i++, p++) {
- if (state->next == state->limit)
- break;
- /* add each partition in use */
- if (SYS_IND(p) == MINIX_PARTITION)
- put_partition(state, state->next++,
- start_sect(p), nr_sects(p));
- }
- strlcat(state->pp_buf, " >\n", PAGE_SIZE);
- }
- put_dev_sector(sect);
-#endif /* CONFIG_MINIX_SUBPARTITION */
-}
-
-static struct {
- unsigned char id;
- void (*parse)(struct parsed_partitions *, sector_t, sector_t, int);
-} subtypes[] = {
- {FREEBSD_PARTITION, parse_freebsd},
- {NETBSD_PARTITION, parse_netbsd},
- {OPENBSD_PARTITION, parse_openbsd},
- {MINIX_PARTITION, parse_minix},
- {UNIXWARE_PARTITION, parse_unixware},
- {SOLARIS_X86_PARTITION, parse_solaris_x86},
- {NEW_SOLARIS_X86_PARTITION, parse_solaris_x86},
- {0, NULL},
-};
-
-int msdos_partition(struct parsed_partitions *state)
-{
- sector_t sector_size = bdev_logical_block_size(state->bdev) / 512;
- Sector sect;
- unsigned char *data;
- struct partition *p;
- struct fat_boot_sector *fb;
- int slot;
-
- data = read_part_sector(state, 0, &sect);
- if (!data)
- return -1;
- if (!msdos_magic_present(data + 510)) {
- put_dev_sector(sect);
- return 0;
- }
-
- if (aix_magic_present(state, data)) {
- put_dev_sector(sect);
- strlcat(state->pp_buf, " [AIX]", PAGE_SIZE);
- return 0;
- }
-
- /*
- * Now that the 55aa signature is present, this is probably
- * either the boot sector of a FAT filesystem or a DOS-type
- * partition table. Reject this in case the boot indicator
- * is not 0 or 0x80.
- */
- p = (struct partition *) (data + 0x1be);
- for (slot = 1; slot <= 4; slot++, p++) {
- if (p->boot_ind != 0 && p->boot_ind != 0x80) {
- /*
- * Even without a valid boot inidicator value
- * its still possible this is valid FAT filesystem
- * without a partition table.
- */
- fb = (struct fat_boot_sector *) data;
- if (slot == 1 && fb->reserved && fb->fats
- && fat_valid_media(fb->media)) {
- strlcat(state->pp_buf, "\n", PAGE_SIZE);
- put_dev_sector(sect);
- return 1;
- } else {
- put_dev_sector(sect);
- return 0;
- }
- }
- }
-
-#ifdef CONFIG_EFI_PARTITION
- p = (struct partition *) (data + 0x1be);
- for (slot = 1 ; slot <= 4 ; slot++, p++) {
- /* If this is an EFI GPT disk, msdos should ignore it. */
- if (SYS_IND(p) == EFI_PMBR_OSTYPE_EFI_GPT) {
- put_dev_sector(sect);
- return 0;
- }
- }
-#endif
- p = (struct partition *) (data + 0x1be);
-
- /*
- * Look for partitions in two passes:
- * First find the primary and DOS-type extended partitions.
- * On the second pass look inside *BSD, Unixware and Solaris partitions.
- */
-
- state->next = 5;
- for (slot = 1 ; slot <= 4 ; slot++, p++) {
- sector_t start = start_sect(p)*sector_size;
- sector_t size = nr_sects(p)*sector_size;
- if (!size)
- continue;
- if (is_extended_partition(p)) {
- /*
- * prevent someone doing mkfs or mkswap on an
- * extended partition, but leave room for LILO
- * FIXME: this uses one logical sector for > 512b
- * sector, although it may not be enough/proper.
- */
- sector_t n = 2;
- n = min(size, max(sector_size, n));
- put_partition(state, slot, start, n);
-
- strlcat(state->pp_buf, " <", PAGE_SIZE);
- parse_extended(state, start, size);
- strlcat(state->pp_buf, " >", PAGE_SIZE);
- continue;
- }
- put_partition(state, slot, start, size);
- if (SYS_IND(p) == LINUX_RAID_PARTITION)
- state->parts[slot].flags = ADDPART_FLAG_RAID;
- if (SYS_IND(p) == DM6_PARTITION)
- strlcat(state->pp_buf, "[DM]", PAGE_SIZE);
- if (SYS_IND(p) == EZD_PARTITION)
- strlcat(state->pp_buf, "[EZD]", PAGE_SIZE);
- }
-
- strlcat(state->pp_buf, "\n", PAGE_SIZE);
-
- /* second pass - output for each on a separate line */
- p = (struct partition *) (0x1be + data);
- for (slot = 1 ; slot <= 4 ; slot++, p++) {
- unsigned char id = SYS_IND(p);
- int n;
-
- if (!nr_sects(p))
- continue;
-
- for (n = 0; subtypes[n].parse && id != subtypes[n].id; n++)
- ;
-
- if (!subtypes[n].parse)
- continue;
- subtypes[n].parse(state, start_sect(p) * sector_size,
- nr_sects(p) * sector_size, slot);
- }
- put_dev_sector(sect);
- return 1;
-}
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