linux-stable/block/partitions/msdos.c
Philippe De Muyter f8f066033b partitions/msdos: enumerate also AIX LVM partitions
Graft AIX partitions enumeration into partitions/msdos.c

There is already a AIX disks detection logic in msdos.c.  When an AIX disk
has been found, and if configured to, call the aix partitions recognizer.
This avoids removal of AIX disks protection from msdos.c, avoids code
duplication, and ensures that AIX partitions enumeration is called before
plain msdos partitions enumeration.

Signed-off-by: Philippe De Muyter <phdm@macqel.be>
Cc: Karel Zak <kzak@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-09 10:33:28 -07:00

579 lines
16 KiB
C

/*
* 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"
#include "aix.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;
}
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 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);
set_info(state, state->next, disksig);
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;
u32 disksig;
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 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);
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 (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;
}