- 根目录:
- fs
- hpfs
- anode.c
/*
* 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 (bp_internal(btree)) {
for (i = 0; i < btree->n_used_nodes; i++)
if (le32_to_cpu(btree->u.internal[i].file_secno) > sec) {
a = le32_to_cpu(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 (le32_to_cpu(btree->u.external[i].file_secno) <= sec &&
le32_to_cpu(btree->u.external[i].file_secno) + le32_to_cpu(btree->u.external[i].length) > sec) {
a = le32_to_cpu(btree->u.external[i].disk_secno) + sec - le32_to_cpu(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 = le32_to_cpu(btree->u.external[i].file_secno);
hpfs_inode->i_disk_sec = le32_to_cpu(btree->u.external[i].disk_secno);
hpfs_inode->i_n_secs = le32_to_cpu(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 (bp_internal(btree)) {
a = le32_to_cpu(btree->u.internal[n].down);
btree->u.internal[n].file_secno = cpu_to_le32(-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 (le32_to_cpu(btree->u.external[n].file_secno) + le32_to_cpu(btree->u.external[n].length) != fsecno) {
hpfs_error(s, "allocated size %08x, trying to add sector %08x, %cnode %08x",
le32_to_cpu(btree->u.external[n].file_secno) + le32_to_cpu(btree->u.external[n].length), fsecno,
fnod?'f':'a', node);
brelse(bh);
return -1;
}
if (hpfs_alloc_if_possible(s, se = le32_to_cpu(btree->u.external[n].disk_secno) + le32_to_cpu(btree->u.external[n].length))) {
le32_add_cpu(&btree->u.external[n].length, 1);
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))) {
brelse(bh);
return -1;
}
fs = n < 0 ? 0 : le32_to_cpu(btree->u.external[n].file_secno) + le32_to_cpu(btree->u.external[n].length);
if (!btree->n_free_nodes) {
up = a != node ? le32_to_cpu(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 = cpu_to_le32(node);
anode->btree.flags |= BP_fnode_parent;
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->flags |= BP_internal;
btree->n_free_nodes = 11;
btree->n_used_nodes = 1;
btree->first_free = cpu_to_le16((char *)&(btree->u.internal[1]) - (char *)btree);
btree->u.internal[0].file_secno = cpu_to_le32(-1);
btree->u.internal[0].down = cpu_to_le32(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++;
le16_add_cpu(&btree->first_free, 12);
btree->u.external[n].disk_secno = cpu_to_le32(se);
btree->u.external[n].file_secno = cpu_to_le32(fs);
btree->u.external[n].length = cpu_to_le32(1);
mark_buffer_dirty(bh);
brelse(bh);
if ((a == node && fnod) || na == -1) return se;
c2 = 0;
while (up != (anode_secno)-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++;
le16_add_cpu(&btree->first_free, 8);
btree->u.internal[n].file_secno = cpu_to_le32(-1);
btree->u.internal[n].down = cpu_to_le32(na);
btree->u.internal[n-1].file_secno = cpu_to_le32(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 = cpu_to_le32(up);
if (up == node && fnod)
anode->btree.flags |= BP_fnode_parent;
else
anode->btree.flags &= ~BP_fnode_parent;
mark_buffer_dirty(bh);
brelse(bh);
}
return se;
}
up = up != node ? le32_to_cpu(anode->up) : -1;
btree->u.internal[btree->n_used_nodes - 1].file_secno = cpu_to_le32(/*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 = cpu_to_le32(up != -1 ? up : ra);*/
anode->btree.flags |= BP_internal;
anode->btree.n_used_nodes = 1;
anode->btree.n_free_nodes = 59;
anode->btree.first_free = cpu_to_le16(16);
anode->btree.u.internal[0].down = cpu_to_le32(a);
anode->btree.u.internal[0].file_secno = cpu_to_le32(-1);
mark_buffer_dirty(bh);
brelse(bh);
if ((anode = hpfs_map_anode(s, a, &bh))) {
anode->up = cpu_to_le32(na);
mark_buffer_dirty(bh);
brelse(bh);
}
} else na = a;
}
if ((anode = hpfs_map_anode(s, na, &bh))) {
anode->up = cpu_to_le32(node);
if (fnod)
anode->btree.flags |= BP_fnode_parent;
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 = cpu_to_le32(node);
memcpy(&ranode->btree, btree, le16_to_cpu(btree->first_free));
if (fnod)
ranode->btree.flags |= BP_fnode_parent;
ranode->btree.n_free_nodes = (bp_internal(&ranode->btree) ? 60 : 40) - ranode->btree.n_used_nodes;
if (bp_internal(&ranode->btree)) for (n = 0; n < ranode->btree.n_used_nodes; n++) {
struct anode *unode;
if ((unode = hpfs_map_anode(s, le32_to_cpu(ranode->u.internal[n].down), &bh1))) {
unode->up = cpu_to_le32(ra);
unode->btree.flags &= ~BP_fnode_parent;
mark_buffer_dirty(bh1);
brelse(bh1);
}
}
btree->flags |= BP_internal;
btree->n_free_nodes = fnod ? 10 : 58;
btree->n_used_nodes = 2;
btree->first_free = cpu_to_le16((char *)&btree->u.internal[2] - (char *)btree);
btree->u.internal[0].file_secno = cpu_to_le32(fs);
btree->u.internal[0].down = cpu_to_le32(ra);
btree->u.internal[1].file_secno = cpu_to_le32(-1);
btree->u.internal[1].down = cpu_to_le32(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 (bp_internal(btree1)) {
ano = le32_to_cpu(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, le32_to_cpu(btree1->u.external[i].disk_secno), le32_to_cpu(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 = le32_to_cpu(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 (le32_to_cpu(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, const 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 = cpu_to_le16(8);
btree->flags &= ~BP_internal;
mark_buffer_dirty(bh);
} else hpfs_free_sectors(s, f, 1);
brelse(bh);
return;
}
while (bp_internal(btree)) {
nodes = btree->n_used_nodes + btree->n_free_nodes;
for (i = 0; i < btree->n_used_nodes; i++)
if (le32_to_cpu(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, le32_to_cpu(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 = cpu_to_le16(8 + 8 * btree->n_used_nodes);
mark_buffer_dirty(bh);
if (btree->u.internal[i].file_secno == cpu_to_le32(secs)) {
brelse(bh);
return;
}
node = le32_to_cpu(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 (le32_to_cpu(btree->u.external[i].file_secno) + le32_to_cpu(btree->u.external[i].length) >= secs) goto ff;
brelse(bh);
return;
ff:
if (secs <= le32_to_cpu(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 (le32_to_cpu(btree->u.external[i].file_secno) + le32_to_cpu(btree->u.external[i].length) > secs) {
hpfs_free_sectors(s, le32_to_cpu(btree->u.external[i].disk_secno) + secs -
le32_to_cpu(btree->u.external[i].file_secno), le32_to_cpu(btree->u.external[i].length)
- secs + le32_to_cpu(btree->u.external[i].file_secno)); /* I hope gcc optimizes this :-) */
btree->u.external[i].length = cpu_to_le32(secs - le32_to_cpu(btree->u.external[i].file_secno));
}
for (j = i + 1; j < btree->n_used_nodes; j++)
hpfs_free_sectors(s, le32_to_cpu(btree->u.external[j].disk_secno), le32_to_cpu(btree->u.external[j].length));
btree->n_used_nodes = i + 1;
btree->n_free_nodes = nodes - btree->n_used_nodes;
btree->first_free = cpu_to_le16(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_is_dir(fnode)) hpfs_remove_btree(s, &fnode->btree);
else hpfs_remove_dtree(s, le32_to_cpu(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(ea))
hpfs_ea_remove(s, ea_sec(ea), ea_in_anode(ea), ea_len(ea));
hpfs_ea_ext_remove(s, le32_to_cpu(fnode->ea_secno), fnode_in_anode(fnode), le32_to_cpu(fnode->ea_size_l));
brelse(bh);
hpfs_free_sectors(s, fno, 1);
}