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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /block/partitions/msdos.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--block/partitions/msdos.c717
1 files changed, 717 insertions, 0 deletions
diff --git a/block/partitions/msdos.c b/block/partitions/msdos.c
new file mode 100644
index 000000000..b5d5c229c
--- /dev/null
+++ b/block/partitions/msdos.c
@@ -0,0 +1,717 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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
+ *
+ * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
+ * updated by Marc Espie <Marc.Espie@openbsd.org>
+ *
+ * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
+ * and Krzysztof G. Baranowski <kgb@knm.org.pl>
+ */
+#include <linux/msdos_fs.h>
+#include <linux/msdos_partition.h>
+
+#include "check.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>
+
+static inline sector_t nr_sects(struct msdos_partition *p)
+{
+ return (sector_t)get_unaligned_le32(&p->nr_sects);
+}
+
+static inline sector_t start_sect(struct msdos_partition *p)
+{
+ return (sector_t)get_unaligned_le32(&p->start_sect);
+}
+
+static inline int is_extended_partition(struct msdos_partition *p)
+{
+ return (p->sys_ind == DOS_EXTENDED_PARTITION ||
+ p->sys_ind == WIN98_EXTENDED_PARTITION ||
+ p->sys_ind == 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 msdos_partition *pt = (struct msdos_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.
+ * Note that old Solaris/x86 partitions use the same indicator as
+ * Linux swap partitions, so we consider that a Linux partition as
+ * well.
+ */
+ for (slot = 1; slot <= 4; slot++, pt++) {
+ if (pt->sys_ind == SOLARIS_X86_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;
+}
+
+static void set_info(struct parsed_partitions *state, int slot,
+ u32 disksig)
+{
+ struct partition_meta_info *info = &state->parts[slot].info;
+
+ snprintf(info->uuid, sizeof(info->uuid), "%08x-%02x", disksig,
+ slot);
+ info->volname[0] = 0;
+ state->parts[slot].has_info = true;
+}
+
+/*
+ * 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,
+ u32 disksig)
+{
+ struct msdos_partition *p;
+ Sector sect;
+ unsigned char *data;
+ sector_t this_sector, this_size;
+ sector_t sector_size;
+ int loopct = 0; /* number of links followed
+ without finding a data partition */
+ int i;
+
+ sector_size = queue_logical_block_size(state->disk->queue) / 512;
+ 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 msdos_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);
+ set_info(state, state->next, disksig);
+ if (p->sys_ind == 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);
+}
+
+#define SOLARIS_X86_NUMSLICE 16
+#define SOLARIS_X86_VTOC_SANE (0x600DDEEEUL)
+
+struct solaris_x86_slice {
+ __le16 s_tag; /* ID tag of partition */
+ __le16 s_flag; /* permission flags */
+ __le32 s_start; /* start sector no of partition */
+ __le32 s_size; /* # of blocks in partition */
+};
+
+struct solaris_x86_vtoc {
+ unsigned int v_bootinfo[3]; /* info needed by mboot */
+ __le32 v_sanity; /* to verify vtoc sanity */
+ __le32 v_version; /* layout version */
+ char v_volume[8]; /* volume name */
+ __le16 v_sectorsz; /* sector size in bytes */
+ __le16 v_nparts; /* number of partitions */
+ unsigned int v_reserved[10]; /* free space */
+ struct solaris_x86_slice
+ v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
+ unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp */
+ char v_asciilabel[128]; /* for compatibility */
+};
+
+/* 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
+}
+
+/* check against BSD src/sys/sys/disklabel.h for consistency */
+#define BSD_DISKMAGIC (0x82564557UL) /* The disk magic number */
+#define BSD_MAXPARTITIONS 16
+#define OPENBSD_MAXPARTITIONS 16
+#define BSD_FS_UNUSED 0 /* disklabel unused partition entry ID */
+struct bsd_disklabel {
+ __le32 d_magic; /* the magic number */
+ __s16 d_type; /* drive type */
+ __s16 d_subtype; /* controller/d_type specific */
+ char d_typename[16]; /* type name, e.g. "eagle" */
+ char d_packname[16]; /* pack identifier */
+ __u32 d_secsize; /* # of bytes per sector */
+ __u32 d_nsectors; /* # of data sectors per track */
+ __u32 d_ntracks; /* # of tracks per cylinder */
+ __u32 d_ncylinders; /* # of data cylinders per unit */
+ __u32 d_secpercyl; /* # of data sectors per cylinder */
+ __u32 d_secperunit; /* # of data sectors per unit */
+ __u16 d_sparespertrack; /* # of spare sectors per track */
+ __u16 d_sparespercyl; /* # of spare sectors per cylinder */
+ __u32 d_acylinders; /* # of alt. cylinders per unit */
+ __u16 d_rpm; /* rotational speed */
+ __u16 d_interleave; /* hardware sector interleave */
+ __u16 d_trackskew; /* sector 0 skew, per track */
+ __u16 d_cylskew; /* sector 0 skew, per cylinder */
+ __u32 d_headswitch; /* head switch time, usec */
+ __u32 d_trkseek; /* track-to-track seek, usec */
+ __u32 d_flags; /* generic flags */
+#define NDDATA 5
+ __u32 d_drivedata[NDDATA]; /* drive-type specific information */
+#define NSPARE 5
+ __u32 d_spare[NSPARE]; /* reserved for future use */
+ __le32 d_magic2; /* the magic number (again) */
+ __le16 d_checksum; /* xor of data incl. partitions */
+
+ /* filesystem and partition information: */
+ __le16 d_npartitions; /* number of partitions in following */
+ __le32 d_bbsize; /* size of boot area at sn0, bytes */
+ __le32 d_sbsize; /* max size of fs superblock, bytes */
+ struct bsd_partition { /* the partition table */
+ __le32 p_size; /* number of sectors in partition */
+ __le32 p_offset; /* starting sector */
+ __le32 p_fsize; /* filesystem basic fragment size */
+ __u8 p_fstype; /* filesystem type, see below */
+ __u8 p_frag; /* filesystem fragments per block */
+ __le16 p_cpg; /* filesystem cylinders per group */
+ } d_partitions[BSD_MAXPARTITIONS]; /* actually may be more */
+};
+
+#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);
+ /* FreeBSD has relative offset if C partition offset is zero */
+ if (memcmp(flavour, "bsd\0", 4) == 0 &&
+ le32_to_cpu(l->d_partitions[2].p_offset) == 0)
+ bsd_start += offset;
+ 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
+}
+
+#define UNIXWARE_DISKMAGIC (0xCA5E600DUL) /* The disk magic number */
+#define UNIXWARE_DISKMAGIC2 (0x600DDEEEUL) /* The slice table magic nr */
+#define UNIXWARE_NUMSLICE 16
+#define UNIXWARE_FS_UNUSED 0 /* Unused slice entry ID */
+
+struct unixware_slice {
+ __le16 s_label; /* label */
+ __le16 s_flags; /* permission flags */
+ __le32 start_sect; /* starting sector */
+ __le32 nr_sects; /* number of sectors in slice */
+};
+
+struct unixware_disklabel {
+ __le32 d_type; /* drive type */
+ __le32 d_magic; /* the magic number */
+ __le32 d_version; /* version number */
+ char d_serial[12]; /* serial number of the device */
+ __le32 d_ncylinders; /* # of data cylinders per device */
+ __le32 d_ntracks; /* # of tracks per cylinder */
+ __le32 d_nsectors; /* # of data sectors per track */
+ __le32 d_secsize; /* # of bytes per sector */
+ __le32 d_part_start; /* # of first sector of this partition*/
+ __le32 d_unknown1[12]; /* ? */
+ __le32 d_alt_tbl; /* byte offset of alternate table */
+ __le32 d_alt_len; /* byte length of alternate table */
+ __le32 d_phys_cyl; /* # of physical cylinders per device */
+ __le32 d_phys_trk; /* # of physical tracks per cylinder */
+ __le32 d_phys_sec; /* # of physical sectors per track */
+ __le32 d_phys_bytes; /* # of physical bytes per sector */
+ __le32 d_unknown2; /* ? */
+ __le32 d_unknown3; /* ? */
+ __le32 d_pad[8]; /* pad */
+
+ struct unixware_vtoc {
+ __le32 v_magic; /* the magic number */
+ __le32 v_version; /* version number */
+ char v_name[8]; /* volume name */
+ __le16 v_nslices; /* # of slices */
+ __le16 v_unknown1; /* ? */
+ __le32 v_reserved[10]; /* reserved */
+ struct unixware_slice
+ v_slice[UNIXWARE_NUMSLICE]; /* slice headers */
+ } vtoc;
+}; /* 408 */
+
+/*
+ * 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
+}
+
+#define MINIX_NR_SUBPARTITIONS 4
+
+/*
+ * 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 msdos_partition *p;
+ int i;
+
+ data = read_part_sector(state, offset, &sect);
+ if (!data)
+ return;
+
+ p = (struct msdos_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) &&
+ p->sys_ind == 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 (p->sys_ind == 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;
+ Sector sect;
+ unsigned char *data;
+ struct msdos_partition *p;
+ struct fat_boot_sector *fb;
+ int slot;
+ u32 disksig;
+
+ sector_size = queue_logical_block_size(state->disk->queue) / 512;
+ data = read_part_sector(state, 0, &sect);
+ if (!data)
+ return -1;
+
+ /*
+ * Note order! (some AIX disks, e.g. unbootable kind,
+ * have no MSDOS 55aa)
+ */
+ if (aix_magic_present(state, data)) {
+ put_dev_sector(sect);
+#ifdef CONFIG_AIX_PARTITION
+ return aix_partition(state);
+#else
+ strlcat(state->pp_buf, " [AIX]", PAGE_SIZE);
+ return 0;
+#endif
+ }
+
+ if (!msdos_magic_present(data + 510)) {
+ put_dev_sector(sect);
+ 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 msdos_partition *) (data + 0x1be);
+ for (slot = 1; slot <= 4; slot++, p++) {
+ if (p->boot_ind != 0 && p->boot_ind != 0x80) {
+ /*
+ * Even without a valid boot indicator 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 msdos_partition *) (data + 0x1be);
+ for (slot = 1 ; slot <= 4 ; slot++, p++) {
+ /* If this is an EFI GPT disk, msdos should ignore it. */
+ if (p->sys_ind == EFI_PMBR_OSTYPE_EFI_GPT) {
+ put_dev_sector(sect);
+ return 0;
+ }
+ }
+#endif
+ p = (struct msdos_partition *) (data + 0x1be);
+
+ disksig = le32_to_cpup((__le32 *)(data + 0x1b8));
+
+ /*
+ * 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, disksig);
+ strlcat(state->pp_buf, " >", PAGE_SIZE);
+ continue;
+ }
+ put_partition(state, slot, start, size);
+ set_info(state, slot, disksig);
+ if (p->sys_ind == LINUX_RAID_PARTITION)
+ state->parts[slot].flags = ADDPART_FLAG_RAID;
+ if (p->sys_ind == DM6_PARTITION)
+ strlcat(state->pp_buf, "[DM]", PAGE_SIZE);
+ if (p->sys_ind == 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 msdos_partition *) (0x1be + data);
+ for (slot = 1 ; slot <= 4 ; slot++, p++) {
+ unsigned char id = p->sys_ind;
+ 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;
+}