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-rw-r--r--fs/hpfs/anode.c491
1 files changed, 491 insertions, 0 deletions
diff --git a/fs/hpfs/anode.c b/fs/hpfs/anode.c
new file mode 100644
index 00000000000..1aa88c4e096
--- /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);
+}