patch-2.3.2 linux/fs/hpfs/anode.c

• Lines: 483
• Date: Thu May 13 23:48:20 1999
• Orig file: v2.3.1/linux/fs/hpfs/anode.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.3.1/linux/fs/hpfs/anode.c linux/fs/hpfs/anode.c
@@ -0,0 +1,482 @@
+/*
+ *  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 (s->s_hpfs_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 (s->s_hpfs_chk) if (hpfs_chk_sectors(s, a, 1, "data")) {
+				brelse(bh);
+				return -1;
+			}
+			if (inode) {
+				inode->i_hpfs_file_sec = btree->u.external[i].file_secno;
+				inode->i_hpfs_disk_sec = btree->u.external[i].disk_secno;
+				inode->i_hpfs_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, 1);
+		brelse(bh);
+		if (s->s_hpfs_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, 1);
+			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 = node;
+	}	
+	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, 1);
+		} 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, 1);
+	brelse(bh);
+	if ((a == node && fnod) || na == -1) return se;
+	c2 = 0;
+	while (up != -1) {
+		if (s->s_hpfs_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, 1);
+			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, 1);
+				brelse(bh);
+			}
+			return se;
+		}
+		up = up != node ? anode->up : -1;
+		btree->u.internal[btree->n_used_nodes - 1].file_secno = /*fs*/-1;
+		if (up == -1) anode->up = ra;
+		mark_buffer_dirty(bh, 1);
+		brelse(bh);
+		a = na;
+		if ((anode = hpfs_alloc_anode(s, a, &na, &bh))) {
+			/*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, 1);
+			brelse(bh);
+			if ((anode = hpfs_map_anode(s, a, &bh))) {
+				anode->up = na;
+				mark_buffer_dirty(bh, 1);
+				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, 1);
+		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, 1);
+			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, 1);
+	brelse(bh);
+	mark_buffer_dirty(bh2, 1);
+	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 (s->s_hpfs_chk)
+			if (hpfs_stop_cycles(s, ano, &d1, &d2, "hpfs_remove_btree #1"))
+				return;
+		anode = hpfs_map_anode(s, ano, &bh);
+		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;
+	if (s->s_hpfs_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;
+	brelse(bh);
+	if (--level) {
+		anode = hpfs_map_anode(s, ano, &bh);
+		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 (s->s_hpfs_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 (s->s_hpfs_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, 1);
+		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, 1);
+		} 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, 1);
+		if (btree->u.internal[i].file_secno == secs) {
+			brelse(bh);
+			return;
+		}
+		node = btree->u.internal[i].down;
+		brelse(bh);
+		if (s->s_hpfs_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, 1);
+	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);
+}