^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * linux/fs/adfs/map.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (C) 1997-2002 Russell King
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #include <linux/statfs.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <asm/unaligned.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include "adfs.h"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) * The ADFS map is basically a set of sectors. Each sector is called a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) * zone which contains a bitstream made up of variable sized fragments.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) * Each bit refers to a set of bytes in the filesystem, defined by
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) * log2bpmb. This may be larger or smaller than the sector size, but
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) * the overall size it describes will always be a round number of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) * sectors. A fragment id is always idlen bits long.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) * < idlen > < n > <1>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) * +---------+-------//---------+---+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) * | frag id | 0000....000000 | 1 |
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) * +---------+-------//---------+---+
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) * The physical disk space used by a fragment is taken from the start of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) * the fragment id up to and including the '1' bit - ie, idlen + n + 1
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) * bits.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) * A fragment id can be repeated multiple times in the whole map for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) * large or fragmented files. The first map zone a fragment starts in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) * is given by fragment id / ids_per_zone - this allows objects to start
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) * from any zone on the disk.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) * Free space is described by a linked list of fragments. Each free
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) * fragment describes free space in the same way as the other fragments,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) * however, the frag id specifies an offset (in map bits) from the end
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) * of this fragment to the start of the next free fragment.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) * Objects stored on the disk are allocated object ids (we use these as
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) * our inode numbers.) Object ids contain a fragment id and an optional
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) * offset. This allows a directory fragment to contain small files
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) * associated with that directory.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) * For the future...
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) static DEFINE_RWLOCK(adfs_map_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) * This is fun. We need to load up to 19 bits from the map at an
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) * arbitrary bit alignment. (We're limited to 19 bits by F+ version 2).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) #define GET_FRAG_ID(_map,_start,_idmask) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) ({ \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) unsigned char *_m = _map + (_start >> 3); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) u32 _frag = get_unaligned_le32(_m); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) _frag >>= (_start & 7); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) _frag & _idmask; \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) })
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) * return the map bit offset of the fragment frag_id in the zone dm.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) * Note that the loop is optimised for best asm code - look at the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) * output of:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) * gcc -D__KERNEL__ -O2 -I../../include -o - -S map.c
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) static int lookup_zone(const struct adfs_discmap *dm, const unsigned int idlen,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) const u32 frag_id, unsigned int *offset)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) const unsigned int endbit = dm->dm_endbit;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) const u32 idmask = (1 << idlen) - 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) unsigned char *map = dm->dm_bh->b_data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) unsigned int start = dm->dm_startbit;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) unsigned int freelink, fragend;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) u32 frag;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) frag = GET_FRAG_ID(map, 8, idmask & 0x7fff);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) freelink = frag ? 8 + frag : 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) do {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) frag = GET_FRAG_ID(map, start, idmask);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) fragend = find_next_bit_le(map, endbit, start + idlen);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) if (fragend >= endbit)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) goto error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) if (start == freelink) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) freelink += frag & 0x7fff;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) } else if (frag == frag_id) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) unsigned int length = fragend + 1 - start;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) if (*offset < length)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) return start + *offset;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) *offset -= length;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) start = fragend + 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) } while (start < endbit);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) return -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) error:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) printk(KERN_ERR "adfs: oversized fragment 0x%x at 0x%x-0x%x\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) frag, start, fragend);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) return -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) * Scan the free space map, for this zone, calculating the total
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) * number of map bits in each free space fragment.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) * Note: idmask is limited to 15 bits [3.2]
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) static unsigned int
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) scan_free_map(struct adfs_sb_info *asb, struct adfs_discmap *dm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) const unsigned int endbit = dm->dm_endbit;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) const unsigned int idlen = asb->s_idlen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) const unsigned int frag_idlen = idlen <= 15 ? idlen : 15;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) const u32 idmask = (1 << frag_idlen) - 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) unsigned char *map = dm->dm_bh->b_data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) unsigned int start = 8, fragend;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) u32 frag;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) unsigned long total = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) * get fragment id
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) frag = GET_FRAG_ID(map, start, idmask);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) * If the freelink is null, then no free fragments
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) * exist in this zone.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) if (frag == 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) do {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) start += frag;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) frag = GET_FRAG_ID(map, start, idmask);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) fragend = find_next_bit_le(map, endbit, start + idlen);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) if (fragend >= endbit)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) goto error;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) total += fragend + 1 - start;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) } while (frag >= idlen + 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) if (frag != 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) printk(KERN_ERR "adfs: undersized free fragment\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) return total;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) error:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) printk(KERN_ERR "adfs: oversized free fragment\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) static int scan_map(struct adfs_sb_info *asb, unsigned int zone,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) const u32 frag_id, unsigned int mapoff)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) const unsigned int idlen = asb->s_idlen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) struct adfs_discmap *dm, *dm_end;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) int result;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) dm = asb->s_map + zone;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) zone = asb->s_map_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) dm_end = asb->s_map + zone;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) do {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) result = lookup_zone(dm, idlen, frag_id, &mapoff);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) if (result != -1)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) goto found;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) dm ++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) if (dm == dm_end)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) dm = asb->s_map;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) } while (--zone > 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) return -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) found:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) result -= dm->dm_startbit;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) result += dm->dm_startblk;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) return result;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) * calculate the amount of free blocks in the map.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) * n=1
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) * total_free = E(free_in_zone_n)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) * nzones
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) void adfs_map_statfs(struct super_block *sb, struct kstatfs *buf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) struct adfs_sb_info *asb = ADFS_SB(sb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) struct adfs_discrecord *dr = adfs_map_discrecord(asb->s_map);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) struct adfs_discmap *dm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) unsigned int total = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) unsigned int zone;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) dm = asb->s_map;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) zone = asb->s_map_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) do {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) total += scan_free_map(asb, dm++);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) } while (--zone > 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) buf->f_blocks = adfs_disc_size(dr) >> sb->s_blocksize_bits;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) buf->f_files = asb->s_ids_per_zone * asb->s_map_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) buf->f_bavail =
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) buf->f_bfree = signed_asl(total, asb->s_map2blk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) int adfs_map_lookup(struct super_block *sb, u32 frag_id, unsigned int offset)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) struct adfs_sb_info *asb = ADFS_SB(sb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) unsigned int zone, mapoff;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) int result;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) * map & root fragment is special - it starts in the center of the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) * disk. The other fragments start at zone (frag / ids_per_zone)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) if (frag_id == ADFS_ROOT_FRAG)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) zone = asb->s_map_size >> 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) zone = frag_id / asb->s_ids_per_zone;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) if (zone >= asb->s_map_size)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) goto bad_fragment;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) /* Convert sector offset to map offset */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) mapoff = signed_asl(offset, -asb->s_map2blk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) read_lock(&adfs_map_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) result = scan_map(asb, zone, frag_id, mapoff);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) read_unlock(&adfs_map_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) if (result > 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) unsigned int secoff;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) /* Calculate sector offset into map block */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) secoff = offset - signed_asl(mapoff, asb->s_map2blk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) return secoff + signed_asl(result, asb->s_map2blk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) adfs_error(sb, "fragment 0x%04x at offset %d not found in map",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) frag_id, offset);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) bad_fragment:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) adfs_error(sb, "invalid fragment 0x%04x (zone = %d, max = %d)",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) frag_id, zone, asb->s_map_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) static unsigned char adfs_calczonecheck(struct super_block *sb, unsigned char *map)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) unsigned int v0, v1, v2, v3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) v0 = v1 = v2 = v3 = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) for (i = sb->s_blocksize - 4; i; i -= 4) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) v0 += map[i] + (v3 >> 8);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) v3 &= 0xff;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) v1 += map[i + 1] + (v0 >> 8);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) v0 &= 0xff;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) v2 += map[i + 2] + (v1 >> 8);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) v1 &= 0xff;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) v3 += map[i + 3] + (v2 >> 8);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) v2 &= 0xff;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) v0 += v3 >> 8;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) v1 += map[1] + (v0 >> 8);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) v2 += map[2] + (v1 >> 8);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) v3 += map[3] + (v2 >> 8);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) return v0 ^ v1 ^ v2 ^ v3;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) static int adfs_checkmap(struct super_block *sb, struct adfs_discmap *dm)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) unsigned char crosscheck = 0, zonecheck = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) int i;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) for (i = 0; i < ADFS_SB(sb)->s_map_size; i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) unsigned char *map;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) map = dm[i].dm_bh->b_data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) if (adfs_calczonecheck(sb, map) != map[0]) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) adfs_error(sb, "zone %d fails zonecheck", i);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) zonecheck = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) crosscheck ^= map[3];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) if (crosscheck != 0xff)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) adfs_error(sb, "crosscheck != 0xff");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) return crosscheck == 0xff && zonecheck;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) * Layout the map - the first zone contains a copy of the disc record,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) * and the last zone must be limited to the size of the filesystem.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) static void adfs_map_layout(struct adfs_discmap *dm, unsigned int nzones,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) struct adfs_discrecord *dr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) unsigned int zone, zone_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) u64 size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) zone_size = (8 << dr->log2secsize) - le16_to_cpu(dr->zone_spare);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) dm[0].dm_bh = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) dm[0].dm_startblk = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) dm[0].dm_startbit = 32 + ADFS_DR_SIZE_BITS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) dm[0].dm_endbit = 32 + zone_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) for (zone = 1; zone < nzones; zone++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) dm[zone].dm_bh = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) dm[zone].dm_startblk = zone * zone_size - ADFS_DR_SIZE_BITS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) dm[zone].dm_startbit = 32;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) dm[zone].dm_endbit = 32 + zone_size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) size = adfs_disc_size(dr) >> dr->log2bpmb;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) size -= (nzones - 1) * zone_size - ADFS_DR_SIZE_BITS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) dm[nzones - 1].dm_endbit = 32 + size;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) static int adfs_map_read(struct adfs_discmap *dm, struct super_block *sb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) unsigned int map_addr, unsigned int nzones)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) unsigned int zone;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) for (zone = 0; zone < nzones; zone++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) dm[zone].dm_bh = sb_bread(sb, map_addr + zone);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) if (!dm[zone].dm_bh)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) return -EIO;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) static void adfs_map_relse(struct adfs_discmap *dm, unsigned int nzones)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) unsigned int zone;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) for (zone = 0; zone < nzones; zone++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) brelse(dm[zone].dm_bh);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) struct adfs_discmap *adfs_read_map(struct super_block *sb, struct adfs_discrecord *dr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) struct adfs_sb_info *asb = ADFS_SB(sb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) struct adfs_discmap *dm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) unsigned int map_addr, zone_size, nzones;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) nzones = dr->nzones | dr->nzones_high << 8;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) zone_size = (8 << dr->log2secsize) - le16_to_cpu(dr->zone_spare);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) asb->s_idlen = dr->idlen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) asb->s_map_size = nzones;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368) asb->s_map2blk = dr->log2bpmb - dr->log2secsize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) asb->s_log2sharesize = dr->log2sharesize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) asb->s_ids_per_zone = zone_size / (asb->s_idlen + 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) map_addr = (nzones >> 1) * zone_size -
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373) ((nzones > 1) ? ADFS_DR_SIZE_BITS : 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) map_addr = signed_asl(map_addr, asb->s_map2blk);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) dm = kmalloc_array(nzones, sizeof(*dm), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) if (dm == NULL) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) adfs_error(sb, "not enough memory");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379) return ERR_PTR(-ENOMEM);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) adfs_map_layout(dm, nzones, dr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) ret = adfs_map_read(dm, sb, map_addr, nzones);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385) if (ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386) adfs_error(sb, "unable to read map");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387) goto error_free;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390) if (adfs_checkmap(sb, dm))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391) return dm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) adfs_error(sb, "map corrupted");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395) error_free:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396) adfs_map_relse(dm, nzones);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397) kfree(dm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398) return ERR_PTR(-EIO);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401) void adfs_free_map(struct super_block *sb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) struct adfs_sb_info *asb = ADFS_SB(sb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405) adfs_map_relse(asb->s_map, asb->s_map_size);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) kfree(asb->s_map);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407) }
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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