diff options
Diffstat (limited to 'fs/hpfs/anode.c')
| -rw-r--r-- | fs/hpfs/anode.c | 491 |
1 files changed, 491 insertions, 0 deletions
diff --git a/fs/hpfs/anode.c b/fs/hpfs/anode.c new file mode 100644 index 0000000..1aa88c4 --- /dev/null +++ b/fs/hpfs/anode.c @@ -0,0 +1,491 @@ +/* + * linux/fs/hpfs/anode.c + * + * Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999 + * + * handling HPFS anode tree that contains file allocation info + */ + +#include "hpfs_fn.h" + +/* Find a sector in allocation tree */ + +secno hpfs_bplus_lookup(struct super_block *s, struct inode *inode, + struct bplus_header *btree, unsigned sec, + struct buffer_head *bh) +{ + anode_secno a = -1; + struct anode *anode; + int i; + int c1, c2 = 0; + go_down: + if (hpfs_sb(s)->sb_chk) if (hpfs_stop_cycles(s, a, &c1, &c2, "hpfs_bplus_lookup")) return -1; + if (btree->internal) { + for (i = 0; i < btree->n_used_nodes; i++) + if (btree->u.internal[i].file_secno > sec) { + a = btree->u.internal[i].down; + brelse(bh); + if (!(anode = hpfs_map_anode(s, a, &bh))) return -1; + btree = &anode->btree; + goto go_down; + } + hpfs_error(s, "sector %08x not found in internal anode %08x", sec, a); + brelse(bh); + return -1; + } + for (i = 0; i < btree->n_used_nodes; i++) + if (btree->u.external[i].file_secno <= sec && + btree->u.external[i].file_secno + btree->u.external[i].length > sec) { + a = btree->u.external[i].disk_secno + sec - btree->u.external[i].file_secno; + if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, a, 1, "data")) { + brelse(bh); + return -1; + } + if (inode) { + struct hpfs_inode_info *hpfs_inode = hpfs_i(inode); + hpfs_inode->i_file_sec = btree->u.external[i].file_secno; + hpfs_inode->i_disk_sec = btree->u.external[i].disk_secno; + hpfs_inode->i_n_secs = btree->u.external[i].length; + } + brelse(bh); + return a; + } + hpfs_error(s, "sector %08x not found in external anode %08x", sec, a); + brelse(bh); + return -1; +} + +/* Add a sector to tree */ + +secno hpfs_add_sector_to_btree(struct super_block *s, secno node, int fnod, unsigned fsecno) +{ + struct bplus_header *btree; + struct anode *anode = NULL, *ranode = NULL; + struct fnode *fnode; + anode_secno a, na = -1, ra, up = -1; + secno se; + struct buffer_head *bh, *bh1, *bh2; + int n; + unsigned fs; + int c1, c2 = 0; + if (fnod) { + if (!(fnode = hpfs_map_fnode(s, node, &bh))) return -1; + btree = &fnode->btree; + } else { + if (!(anode = hpfs_map_anode(s, node, &bh))) return -1; + btree = &anode->btree; + } + a = node; + go_down: + if ((n = btree->n_used_nodes - 1) < -!!fnod) { + hpfs_error(s, "anode %08x has no entries", a); + brelse(bh); + return -1; + } + if (btree->internal) { + a = btree->u.internal[n].down; + btree->u.internal[n].file_secno = -1; + mark_buffer_dirty(bh); + brelse(bh); + if (hpfs_sb(s)->sb_chk) + if (hpfs_stop_cycles(s, a, &c1, &c2, "hpfs_add_sector_to_btree #1")) return -1; + if (!(anode = hpfs_map_anode(s, a, &bh))) return -1; + btree = &anode->btree; + goto go_down; + } + if (n >= 0) { + if (btree->u.external[n].file_secno + btree->u.external[n].length != fsecno) { + hpfs_error(s, "allocated size %08x, trying to add sector %08x, %cnode %08x", + btree->u.external[n].file_secno + btree->u.external[n].length, fsecno, + fnod?'f':'a', node); + brelse(bh); + return -1; + } + if (hpfs_alloc_if_possible(s, se = btree->u.external[n].disk_secno + btree->u.external[n].length)) { + btree->u.external[n].length++; + mark_buffer_dirty(bh); + brelse(bh); + return se; + } + } else { + if (fsecno) { + hpfs_error(s, "empty file %08x, trying to add sector %08x", node, fsecno); + brelse(bh); + return -1; + } + se = !fnod ? node : (node + 16384) & ~16383; + } + if (!(se = hpfs_alloc_sector(s, se, 1, fsecno*ALLOC_M>ALLOC_FWD_MAX ? ALLOC_FWD_MAX : fsecno*ALLOC_M<ALLOC_FWD_MIN ? ALLOC_FWD_MIN : fsecno*ALLOC_M, 1))) { + brelse(bh); + return -1; + } + fs = n < 0 ? 0 : btree->u.external[n].file_secno + btree->u.external[n].length; + if (!btree->n_free_nodes) { + up = a != node ? anode->up : -1; + if (!(anode = hpfs_alloc_anode(s, a, &na, &bh1))) { + brelse(bh); + hpfs_free_sectors(s, se, 1); + return -1; + } + if (a == node && fnod) { + anode->up = node; + anode->btree.fnode_parent = 1; + anode->btree.n_used_nodes = btree->n_used_nodes; + anode->btree.first_free = btree->first_free; + anode->btree.n_free_nodes = 40 - anode->btree.n_used_nodes; + memcpy(&anode->u, &btree->u, btree->n_used_nodes * 12); + btree->internal = 1; + btree->n_free_nodes = 11; + btree->n_used_nodes = 1; + btree->first_free = (char *)&(btree->u.internal[1]) - (char *)btree; + btree->u.internal[0].file_secno = -1; + btree->u.internal[0].down = na; + mark_buffer_dirty(bh); + } else if (!(ranode = hpfs_alloc_anode(s, /*a*/0, &ra, &bh2))) { + brelse(bh); + brelse(bh1); + hpfs_free_sectors(s, se, 1); + hpfs_free_sectors(s, na, 1); + return -1; + } + brelse(bh); + bh = bh1; + btree = &anode->btree; + } + btree->n_free_nodes--; n = btree->n_used_nodes++; + btree->first_free += 12; + btree->u.external[n].disk_secno = se; + btree->u.external[n].file_secno = fs; + btree->u.external[n].length = 1; + mark_buffer_dirty(bh); + brelse(bh); + if ((a == node && fnod) || na == -1) return se; + c2 = 0; + while (up != -1) { + struct anode *new_anode; + if (hpfs_sb(s)->sb_chk) + if (hpfs_stop_cycles(s, up, &c1, &c2, "hpfs_add_sector_to_btree #2")) return -1; + if (up != node || !fnod) { + if (!(anode = hpfs_map_anode(s, up, &bh))) return -1; + btree = &anode->btree; + } else { + if (!(fnode = hpfs_map_fnode(s, up, &bh))) return -1; + btree = &fnode->btree; + } + if (btree->n_free_nodes) { + btree->n_free_nodes--; n = btree->n_used_nodes++; + btree->first_free += 8; + btree->u.internal[n].file_secno = -1; + btree->u.internal[n].down = na; + btree->u.internal[n-1].file_secno = fs; + mark_buffer_dirty(bh); + brelse(bh); + brelse(bh2); + hpfs_free_sectors(s, ra, 1); + if ((anode = hpfs_map_anode(s, na, &bh))) { + anode->up = up; + anode->btree.fnode_parent = up == node && fnod; + mark_buffer_dirty(bh); + brelse(bh); + } + return se; + } + up = up != node ? anode->up : -1; + btree->u.internal[btree->n_used_nodes - 1].file_secno = /*fs*/-1; + mark_buffer_dirty(bh); + brelse(bh); + a = na; + if ((new_anode = hpfs_alloc_anode(s, a, &na, &bh))) { + anode = new_anode; + /*anode->up = up != -1 ? up : ra;*/ + anode->btree.internal = 1; + anode->btree.n_used_nodes = 1; + anode->btree.n_free_nodes = 59; + anode->btree.first_free = 16; + anode->btree.u.internal[0].down = a; + anode->btree.u.internal[0].file_secno = -1; + mark_buffer_dirty(bh); + brelse(bh); + if ((anode = hpfs_map_anode(s, a, &bh))) { + anode->up = na; + mark_buffer_dirty(bh); + brelse(bh); + } + } else na = a; + } + if ((anode = hpfs_map_anode(s, na, &bh))) { + anode->up = node; + if (fnod) anode->btree.fnode_parent = 1; + mark_buffer_dirty(bh); + brelse(bh); + } + if (!fnod) { + if (!(anode = hpfs_map_anode(s, node, &bh))) { + brelse(bh2); + return -1; + } + btree = &anode->btree; + } else { + if (!(fnode = hpfs_map_fnode(s, node, &bh))) { + brelse(bh2); + return -1; + } + btree = &fnode->btree; + } + ranode->up = node; + memcpy(&ranode->btree, btree, btree->first_free); + if (fnod) ranode->btree.fnode_parent = 1; + ranode->btree.n_free_nodes = (ranode->btree.internal ? 60 : 40) - ranode->btree.n_used_nodes; + if (ranode->btree.internal) for (n = 0; n < ranode->btree.n_used_nodes; n++) { + struct anode *unode; + if ((unode = hpfs_map_anode(s, ranode->u.internal[n].down, &bh1))) { + unode->up = ra; + unode->btree.fnode_parent = 0; + mark_buffer_dirty(bh1); + brelse(bh1); + } + } + btree->internal = 1; + btree->n_free_nodes = fnod ? 10 : 58; + btree->n_used_nodes = 2; + btree->first_free = (char *)&btree->u.internal[2] - (char *)btree; + btree->u.internal[0].file_secno = fs; + btree->u.internal[0].down = ra; + btree->u.internal[1].file_secno = -1; + btree->u.internal[1].down = na; + mark_buffer_dirty(bh); + brelse(bh); + mark_buffer_dirty(bh2); + brelse(bh2); + return se; +} + +/* + * Remove allocation tree. Recursion would look much nicer but + * I want to avoid it because it can cause stack overflow. + */ + +void hpfs_remove_btree(struct super_block *s, struct bplus_header *btree) +{ + struct bplus_header *btree1 = btree; + struct anode *anode = NULL; + anode_secno ano = 0, oano; + struct buffer_head *bh; + int level = 0; + int pos = 0; + int i; + int c1, c2 = 0; + int d1, d2; + go_down: + d2 = 0; + while (btree1->internal) { + ano = btree1->u.internal[pos].down; + if (level) brelse(bh); + if (hpfs_sb(s)->sb_chk) + if (hpfs_stop_cycles(s, ano, &d1, &d2, "hpfs_remove_btree #1")) + return; + if (!(anode = hpfs_map_anode(s, ano, &bh))) return; + btree1 = &anode->btree; + level++; + pos = 0; + } + for (i = 0; i < btree1->n_used_nodes; i++) + hpfs_free_sectors(s, btree1->u.external[i].disk_secno, btree1->u.external[i].length); + go_up: + if (!level) return; + brelse(bh); + if (hpfs_sb(s)->sb_chk) + if (hpfs_stop_cycles(s, ano, &c1, &c2, "hpfs_remove_btree #2")) return; + hpfs_free_sectors(s, ano, 1); + oano = ano; + ano = anode->up; + if (--level) { + if (!(anode = hpfs_map_anode(s, ano, &bh))) return; + btree1 = &anode->btree; + } else btree1 = btree; + for (i = 0; i < btree1->n_used_nodes; i++) { + if (btree1->u.internal[i].down == oano) { + if ((pos = i + 1) < btree1->n_used_nodes) + goto go_down; + else + goto go_up; + } + } + hpfs_error(s, + "reference to anode %08x not found in anode %08x " + "(probably bad up pointer)", + oano, level ? ano : -1); + if (level) + brelse(bh); +} + +/* Just a wrapper around hpfs_bplus_lookup .. used for reading eas */ + +static secno anode_lookup(struct super_block *s, anode_secno a, unsigned sec) +{ + struct anode *anode; + struct buffer_head *bh; + if (!(anode = hpfs_map_anode(s, a, &bh))) return -1; + return hpfs_bplus_lookup(s, NULL, &anode->btree, sec, bh); +} + +int hpfs_ea_read(struct super_block *s, secno a, int ano, unsigned pos, + unsigned len, char *buf) +{ + struct buffer_head *bh; + char *data; + secno sec; + unsigned l; + while (len) { + if (ano) { + if ((sec = anode_lookup(s, a, pos >> 9)) == -1) + return -1; + } else sec = a + (pos >> 9); + if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, sec, 1, "ea #1")) return -1; + if (!(data = hpfs_map_sector(s, sec, &bh, (len - 1) >> 9))) + return -1; + l = 0x200 - (pos & 0x1ff); if (l > len) l = len; + memcpy(buf, data + (pos & 0x1ff), l); + brelse(bh); + buf += l; pos += l; len -= l; + } + return 0; +} + +int hpfs_ea_write(struct super_block *s, secno a, int ano, unsigned pos, + unsigned len, char *buf) +{ + struct buffer_head *bh; + char *data; + secno sec; + unsigned l; + while (len) { + if (ano) { + if ((sec = anode_lookup(s, a, pos >> 9)) == -1) + return -1; + } else sec = a + (pos >> 9); + if (hpfs_sb(s)->sb_chk) if (hpfs_chk_sectors(s, sec, 1, "ea #2")) return -1; + if (!(data = hpfs_map_sector(s, sec, &bh, (len - 1) >> 9))) + return -1; + l = 0x200 - (pos & 0x1ff); if (l > len) l = len; + memcpy(data + (pos & 0x1ff), buf, l); + mark_buffer_dirty(bh); + brelse(bh); + buf += l; pos += l; len -= l; + } + return 0; +} + +void hpfs_ea_remove(struct super_block *s, secno a, int ano, unsigned len) +{ + struct anode *anode; + struct buffer_head *bh; + if (ano) { + if (!(anode = hpfs_map_anode(s, a, &bh))) return; + hpfs_remove_btree(s, &anode->btree); + brelse(bh); + hpfs_free_sectors(s, a, 1); + } else hpfs_free_sectors(s, a, (len + 511) >> 9); +} + +/* Truncate allocation tree. Doesn't join anodes - I hope it doesn't matter */ + +void hpfs_truncate_btree(struct super_block *s, secno f, int fno, unsigned secs) +{ + struct fnode *fnode; + struct anode *anode; + struct buffer_head *bh; + struct bplus_header *btree; + anode_secno node = f; + int i, j, nodes; + int c1, c2 = 0; + if (fno) { + if (!(fnode = hpfs_map_fnode(s, f, &bh))) return; + btree = &fnode->btree; + } else { + if (!(anode = hpfs_map_anode(s, f, &bh))) return; + btree = &anode->btree; + } + if (!secs) { + hpfs_remove_btree(s, btree); + if (fno) { + btree->n_free_nodes = 8; + btree->n_used_nodes = 0; + btree->first_free = 8; + btree->internal = 0; + mark_buffer_dirty(bh); + } else hpfs_free_sectors(s, f, 1); + brelse(bh); + return; + } + while (btree->internal) { + nodes = btree->n_used_nodes + btree->n_free_nodes; + for (i = 0; i < btree->n_used_nodes; i++) + if (btree->u.internal[i].file_secno >= secs) goto f; + brelse(bh); + hpfs_error(s, "internal btree %08x doesn't end with -1", node); + return; + f: + for (j = i + 1; j < btree->n_used_nodes; j++) + hpfs_ea_remove(s, btree->u.internal[j].down, 1, 0); + btree->n_used_nodes = i + 1; + btree->n_free_nodes = nodes - btree->n_used_nodes; + btree->first_free = 8 + 8 * btree->n_used_nodes; + mark_buffer_dirty(bh); + if (btree->u.internal[i].file_secno == secs) { + brelse(bh); + return; + } + node = btree->u.internal[i].down; + brelse(bh); + if (hpfs_sb(s)->sb_chk) + if (hpfs_stop_cycles(s, node, &c1, &c2, "hpfs_truncate_btree")) + return; + if (!(anode = hpfs_map_anode(s, node, &bh))) return; + btree = &anode->btree; + } + nodes = btree->n_used_nodes + btree->n_free_nodes; + for (i = 0; i < btree->n_used_nodes; i++) + if (btree->u.external[i].file_secno + btree->u.external[i].length >= secs) goto ff; + brelse(bh); + return; + ff: + if (secs <= btree->u.external[i].file_secno) { + hpfs_error(s, "there is an allocation error in file %08x, sector %08x", f, secs); + if (i) i--; + } + else if (btree->u.external[i].file_secno + btree->u.external[i].length > secs) { + hpfs_free_sectors(s, btree->u.external[i].disk_secno + secs - + btree->u.external[i].file_secno, btree->u.external[i].length + - secs + btree->u.external[i].file_secno); /* I hope gcc optimizes this :-) */ + btree->u.external[i].length = secs - btree->u.external[i].file_secno; + } + for (j = i + 1; j < btree->n_used_nodes; j++) + hpfs_free_sectors(s, btree->u.external[j].disk_secno, btree->u.external[j].length); + btree->n_used_nodes = i + 1; + btree->n_free_nodes = nodes - btree->n_used_nodes; + btree->first_free = 8 + 12 * btree->n_used_nodes; + mark_buffer_dirty(bh); + brelse(bh); +} + +/* Remove file or directory and it's eas - note that directory must + be empty when this is called. */ + +void hpfs_remove_fnode(struct super_block *s, fnode_secno fno) +{ + struct buffer_head *bh; + struct fnode *fnode; + struct extended_attribute *ea; + struct extended_attribute *ea_end; + if (!(fnode = hpfs_map_fnode(s, fno, &bh))) return; + if (!fnode->dirflag) hpfs_remove_btree(s, &fnode->btree); + else hpfs_remove_dtree(s, fnode->u.external[0].disk_secno); + ea_end = fnode_end_ea(fnode); + for (ea = fnode_ea(fnode); ea < ea_end; ea = next_ea(ea)) + if (ea->indirect) + hpfs_ea_remove(s, ea_sec(ea), ea->anode, ea_len(ea)); + hpfs_ea_ext_remove(s, fnode->ea_secno, fnode->ea_anode, fnode->ea_size_l); + brelse(bh); + hpfs_free_sectors(s, fno, 1); +} |
