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-rw-r--r--block/partitions/acorn.c550
1 files changed, 550 insertions, 0 deletions
diff --git a/block/partitions/acorn.c b/block/partitions/acorn.c
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+++ b/block/partitions/acorn.c
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+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 1996-2000 Russell King.
+ *
+ * Scan ADFS partitions on hard disk drives. Unfortunately, there
+ * isn't a standard for partitioning drives on Acorn machines, so
+ * every single manufacturer of SCSI and IDE cards created their own
+ * method.
+ */
+#include <linux/buffer_head.h>
+#include <linux/adfs_fs.h>
+
+#include "check.h"
+
+/*
+ * Partition types. (Oh for reusability)
+ */
+#define PARTITION_RISCIX_MFM 1
+#define PARTITION_RISCIX_SCSI 2
+#define PARTITION_LINUX 9
+
+#if defined(CONFIG_ACORN_PARTITION_CUMANA) || \
+ defined(CONFIG_ACORN_PARTITION_ADFS)
+static struct adfs_discrecord *
+adfs_partition(struct parsed_partitions *state, char *name, char *data,
+ unsigned long first_sector, int slot)
+{
+ struct adfs_discrecord *dr;
+ unsigned int nr_sects;
+
+ if (adfs_checkbblk(data))
+ return NULL;
+
+ dr = (struct adfs_discrecord *)(data + 0x1c0);
+
+ if (dr->disc_size == 0 && dr->disc_size_high == 0)
+ return NULL;
+
+ nr_sects = (le32_to_cpu(dr->disc_size_high) << 23) |
+ (le32_to_cpu(dr->disc_size) >> 9);
+
+ if (name) {
+ strlcat(state->pp_buf, " [", PAGE_SIZE);
+ strlcat(state->pp_buf, name, PAGE_SIZE);
+ strlcat(state->pp_buf, "]", PAGE_SIZE);
+ }
+ put_partition(state, slot, first_sector, nr_sects);
+ return dr;
+}
+#endif
+
+#ifdef CONFIG_ACORN_PARTITION_RISCIX
+
+struct riscix_part {
+ __le32 start;
+ __le32 length;
+ __le32 one;
+ char name[16];
+};
+
+struct riscix_record {
+ __le32 magic;
+#define RISCIX_MAGIC cpu_to_le32(0x4a657320)
+ __le32 date;
+ struct riscix_part part[8];
+};
+
+#if defined(CONFIG_ACORN_PARTITION_CUMANA) || \
+ defined(CONFIG_ACORN_PARTITION_ADFS)
+static int riscix_partition(struct parsed_partitions *state,
+ unsigned long first_sect, int slot,
+ unsigned long nr_sects)
+{
+ Sector sect;
+ struct riscix_record *rr;
+
+ rr = read_part_sector(state, first_sect, &sect);
+ if (!rr)
+ return -1;
+
+ strlcat(state->pp_buf, " [RISCiX]", PAGE_SIZE);
+
+
+ if (rr->magic == RISCIX_MAGIC) {
+ unsigned long size = nr_sects > 2 ? 2 : nr_sects;
+ int part;
+
+ strlcat(state->pp_buf, " <", PAGE_SIZE);
+
+ put_partition(state, slot++, first_sect, size);
+ for (part = 0; part < 8; part++) {
+ if (rr->part[part].one &&
+ memcmp(rr->part[part].name, "All\0", 4)) {
+ put_partition(state, slot++,
+ le32_to_cpu(rr->part[part].start),
+ le32_to_cpu(rr->part[part].length));
+ strlcat(state->pp_buf, "(", PAGE_SIZE);
+ strlcat(state->pp_buf, rr->part[part].name, PAGE_SIZE);
+ strlcat(state->pp_buf, ")", PAGE_SIZE);
+ }
+ }
+
+ strlcat(state->pp_buf, " >\n", PAGE_SIZE);
+ } else {
+ put_partition(state, slot++, first_sect, nr_sects);
+ }
+
+ put_dev_sector(sect);
+ return slot;
+}
+#endif
+#endif
+
+#define LINUX_NATIVE_MAGIC 0xdeafa1de
+#define LINUX_SWAP_MAGIC 0xdeafab1e
+
+struct linux_part {
+ __le32 magic;
+ __le32 start_sect;
+ __le32 nr_sects;
+};
+
+#if defined(CONFIG_ACORN_PARTITION_CUMANA) || \
+ defined(CONFIG_ACORN_PARTITION_ADFS)
+static int linux_partition(struct parsed_partitions *state,
+ unsigned long first_sect, int slot,
+ unsigned long nr_sects)
+{
+ Sector sect;
+ struct linux_part *linuxp;
+ unsigned long size = nr_sects > 2 ? 2 : nr_sects;
+
+ strlcat(state->pp_buf, " [Linux]", PAGE_SIZE);
+
+ put_partition(state, slot++, first_sect, size);
+
+ linuxp = read_part_sector(state, first_sect, &sect);
+ if (!linuxp)
+ return -1;
+
+ strlcat(state->pp_buf, " <", PAGE_SIZE);
+ while (linuxp->magic == cpu_to_le32(LINUX_NATIVE_MAGIC) ||
+ linuxp->magic == cpu_to_le32(LINUX_SWAP_MAGIC)) {
+ if (slot == state->limit)
+ break;
+ put_partition(state, slot++, first_sect +
+ le32_to_cpu(linuxp->start_sect),
+ le32_to_cpu(linuxp->nr_sects));
+ linuxp ++;
+ }
+ strlcat(state->pp_buf, " >", PAGE_SIZE);
+
+ put_dev_sector(sect);
+ return slot;
+}
+#endif
+
+#ifdef CONFIG_ACORN_PARTITION_CUMANA
+int adfspart_check_CUMANA(struct parsed_partitions *state)
+{
+ unsigned long first_sector = 0;
+ unsigned int start_blk = 0;
+ Sector sect;
+ unsigned char *data;
+ char *name = "CUMANA/ADFS";
+ int first = 1;
+ int slot = 1;
+
+ /*
+ * Try Cumana style partitions - sector 6 contains ADFS boot block
+ * with pointer to next 'drive'.
+ *
+ * There are unknowns in this code - is the 'cylinder number' of the
+ * next partition relative to the start of this one - I'm assuming
+ * it is.
+ *
+ * Also, which ID did Cumana use?
+ *
+ * This is totally unfinished, and will require more work to get it
+ * going. Hence it is totally untested.
+ */
+ do {
+ struct adfs_discrecord *dr;
+ unsigned int nr_sects;
+
+ data = read_part_sector(state, start_blk * 2 + 6, &sect);
+ if (!data)
+ return -1;
+
+ if (slot == state->limit)
+ break;
+
+ dr = adfs_partition(state, name, data, first_sector, slot++);
+ if (!dr)
+ break;
+
+ name = NULL;
+
+ nr_sects = (data[0x1fd] + (data[0x1fe] << 8)) *
+ (dr->heads + (dr->lowsector & 0x40 ? 1 : 0)) *
+ dr->secspertrack;
+
+ if (!nr_sects)
+ break;
+
+ first = 0;
+ first_sector += nr_sects;
+ start_blk += nr_sects >> (BLOCK_SIZE_BITS - 9);
+ nr_sects = 0; /* hmm - should be partition size */
+
+ switch (data[0x1fc] & 15) {
+ case 0: /* No partition / ADFS? */
+ break;
+
+#ifdef CONFIG_ACORN_PARTITION_RISCIX
+ case PARTITION_RISCIX_SCSI:
+ /* RISCiX - we don't know how to find the next one. */
+ slot = riscix_partition(state, first_sector, slot,
+ nr_sects);
+ break;
+#endif
+
+ case PARTITION_LINUX:
+ slot = linux_partition(state, first_sector, slot,
+ nr_sects);
+ break;
+ }
+ put_dev_sector(sect);
+ if (slot == -1)
+ return -1;
+ } while (1);
+ put_dev_sector(sect);
+ return first ? 0 : 1;
+}
+#endif
+
+#ifdef CONFIG_ACORN_PARTITION_ADFS
+/*
+ * Purpose: allocate ADFS partitions.
+ *
+ * Params : hd - pointer to gendisk structure to store partition info.
+ * dev - device number to access.
+ *
+ * Returns: -1 on error, 0 for no ADFS boot sector, 1 for ok.
+ *
+ * Alloc : hda = whole drive
+ * hda1 = ADFS partition on first drive.
+ * hda2 = non-ADFS partition.
+ */
+int adfspart_check_ADFS(struct parsed_partitions *state)
+{
+ unsigned long start_sect, nr_sects, sectscyl, heads;
+ Sector sect;
+ unsigned char *data;
+ struct adfs_discrecord *dr;
+ unsigned char id;
+ int slot = 1;
+
+ data = read_part_sector(state, 6, &sect);
+ if (!data)
+ return -1;
+
+ dr = adfs_partition(state, "ADFS", data, 0, slot++);
+ if (!dr) {
+ put_dev_sector(sect);
+ return 0;
+ }
+
+ heads = dr->heads + ((dr->lowsector >> 6) & 1);
+ sectscyl = dr->secspertrack * heads;
+ start_sect = ((data[0x1fe] << 8) + data[0x1fd]) * sectscyl;
+ id = data[0x1fc] & 15;
+ put_dev_sector(sect);
+
+ /*
+ * Work out start of non-adfs partition.
+ */
+ nr_sects = (state->bdev->bd_inode->i_size >> 9) - start_sect;
+
+ if (start_sect) {
+ switch (id) {
+#ifdef CONFIG_ACORN_PARTITION_RISCIX
+ case PARTITION_RISCIX_SCSI:
+ case PARTITION_RISCIX_MFM:
+ slot = riscix_partition(state, start_sect, slot,
+ nr_sects);
+ break;
+#endif
+
+ case PARTITION_LINUX:
+ slot = linux_partition(state, start_sect, slot,
+ nr_sects);
+ break;
+ }
+ }
+ strlcat(state->pp_buf, "\n", PAGE_SIZE);
+ return 1;
+}
+#endif
+
+#ifdef CONFIG_ACORN_PARTITION_ICS
+
+struct ics_part {
+ __le32 start;
+ __le32 size;
+};
+
+static int adfspart_check_ICSLinux(struct parsed_partitions *state,
+ unsigned long block)
+{
+ Sector sect;
+ unsigned char *data = read_part_sector(state, block, &sect);
+ int result = 0;
+
+ if (data) {
+ if (memcmp(data, "LinuxPart", 9) == 0)
+ result = 1;
+ put_dev_sector(sect);
+ }
+
+ return result;
+}
+
+/*
+ * Check for a valid ICS partition using the checksum.
+ */
+static inline int valid_ics_sector(const unsigned char *data)
+{
+ unsigned long sum;
+ int i;
+
+ for (i = 0, sum = 0x50617274; i < 508; i++)
+ sum += data[i];
+
+ sum -= le32_to_cpu(*(__le32 *)(&data[508]));
+
+ return sum == 0;
+}
+
+/*
+ * Purpose: allocate ICS partitions.
+ * Params : hd - pointer to gendisk structure to store partition info.
+ * dev - device number to access.
+ * Returns: -1 on error, 0 for no ICS table, 1 for partitions ok.
+ * Alloc : hda = whole drive
+ * hda1 = ADFS partition 0 on first drive.
+ * hda2 = ADFS partition 1 on first drive.
+ * ..etc..
+ */
+int adfspart_check_ICS(struct parsed_partitions *state)
+{
+ const unsigned char *data;
+ const struct ics_part *p;
+ int slot;
+ Sector sect;
+
+ /*
+ * Try ICS style partitions - sector 0 contains partition info.
+ */
+ data = read_part_sector(state, 0, &sect);
+ if (!data)
+ return -1;
+
+ if (!valid_ics_sector(data)) {
+ put_dev_sector(sect);
+ return 0;
+ }
+
+ strlcat(state->pp_buf, " [ICS]", PAGE_SIZE);
+
+ for (slot = 1, p = (const struct ics_part *)data; p->size; p++) {
+ u32 start = le32_to_cpu(p->start);
+ s32 size = le32_to_cpu(p->size); /* yes, it's signed. */
+
+ if (slot == state->limit)
+ break;
+
+ /*
+ * Negative sizes tell the RISC OS ICS driver to ignore
+ * this partition - in effect it says that this does not
+ * contain an ADFS filesystem.
+ */
+ if (size < 0) {
+ size = -size;
+
+ /*
+ * Our own extension - We use the first sector
+ * of the partition to identify what type this
+ * partition is. We must not make this visible
+ * to the filesystem.
+ */
+ if (size > 1 && adfspart_check_ICSLinux(state, start)) {
+ start += 1;
+ size -= 1;
+ }
+ }
+
+ if (size)
+ put_partition(state, slot++, start, size);
+ }
+
+ put_dev_sector(sect);
+ strlcat(state->pp_buf, "\n", PAGE_SIZE);
+ return 1;
+}
+#endif
+
+#ifdef CONFIG_ACORN_PARTITION_POWERTEC
+struct ptec_part {
+ __le32 unused1;
+ __le32 unused2;
+ __le32 start;
+ __le32 size;
+ __le32 unused5;
+ char type[8];
+};
+
+static inline int valid_ptec_sector(const unsigned char *data)
+{
+ unsigned char checksum = 0x2a;
+ int i;
+
+ /*
+ * If it looks like a PC/BIOS partition, then it
+ * probably isn't PowerTec.
+ */
+ if (data[510] == 0x55 && data[511] == 0xaa)
+ return 0;
+
+ for (i = 0; i < 511; i++)
+ checksum += data[i];
+
+ return checksum == data[511];
+}
+
+/*
+ * Purpose: allocate ICS partitions.
+ * Params : hd - pointer to gendisk structure to store partition info.
+ * dev - device number to access.
+ * Returns: -1 on error, 0 for no ICS table, 1 for partitions ok.
+ * Alloc : hda = whole drive
+ * hda1 = ADFS partition 0 on first drive.
+ * hda2 = ADFS partition 1 on first drive.
+ * ..etc..
+ */
+int adfspart_check_POWERTEC(struct parsed_partitions *state)
+{
+ Sector sect;
+ const unsigned char *data;
+ const struct ptec_part *p;
+ int slot = 1;
+ int i;
+
+ data = read_part_sector(state, 0, &sect);
+ if (!data)
+ return -1;
+
+ if (!valid_ptec_sector(data)) {
+ put_dev_sector(sect);
+ return 0;
+ }
+
+ strlcat(state->pp_buf, " [POWERTEC]", PAGE_SIZE);
+
+ for (i = 0, p = (const struct ptec_part *)data; i < 12; i++, p++) {
+ u32 start = le32_to_cpu(p->start);
+ u32 size = le32_to_cpu(p->size);
+
+ if (size)
+ put_partition(state, slot++, start, size);
+ }
+
+ put_dev_sector(sect);
+ strlcat(state->pp_buf, "\n", PAGE_SIZE);
+ return 1;
+}
+#endif
+
+#ifdef CONFIG_ACORN_PARTITION_EESOX
+struct eesox_part {
+ char magic[6];
+ char name[10];
+ __le32 start;
+ __le32 unused6;
+ __le32 unused7;
+ __le32 unused8;
+};
+
+/*
+ * Guess who created this format?
+ */
+static const char eesox_name[] = {
+ 'N', 'e', 'i', 'l', ' ',
+ 'C', 'r', 'i', 't', 'c', 'h', 'e', 'l', 'l', ' ', ' '
+};
+
+/*
+ * EESOX SCSI partition format.
+ *
+ * This is a goddamned awful partition format. We don't seem to store
+ * the size of the partition in this table, only the start addresses.
+ *
+ * There are two possibilities where the size comes from:
+ * 1. The individual ADFS boot block entries that are placed on the disk.
+ * 2. The start address of the next entry.
+ */
+int adfspart_check_EESOX(struct parsed_partitions *state)
+{
+ Sector sect;
+ const unsigned char *data;
+ unsigned char buffer[256];
+ struct eesox_part *p;
+ sector_t start = 0;
+ int i, slot = 1;
+
+ data = read_part_sector(state, 7, &sect);
+ if (!data)
+ return -1;
+
+ /*
+ * "Decrypt" the partition table. God knows why...
+ */
+ for (i = 0; i < 256; i++)
+ buffer[i] = data[i] ^ eesox_name[i & 15];
+
+ put_dev_sector(sect);
+
+ for (i = 0, p = (struct eesox_part *)buffer; i < 8; i++, p++) {
+ sector_t next;
+
+ if (memcmp(p->magic, "Eesox", 6))
+ break;
+
+ next = le32_to_cpu(p->start);
+ if (i)
+ put_partition(state, slot++, start, next - start);
+ start = next;
+ }
+
+ if (i != 0) {
+ sector_t size;
+
+ size = get_capacity(state->bdev->bd_disk);
+ put_partition(state, slot++, start, size - start);
+ strlcat(state->pp_buf, "\n", PAGE_SIZE);
+ }
+
+ return i ? 1 : 0;
+}
+#endif
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