1 // SPDX-License-Identifier: GPL-2.0-only
3 * linux/fs/adfs/dir_fplus.c
5 * Copyright (C) 1997-1999 Russell King
7 #include <linux/buffer_head.h>
8 #include <linux/slab.h>
10 #include "dir_fplus.h"
13 adfs_fplus_read(struct super_block *sb, unsigned int id, unsigned int sz, struct adfs_dir *dir)
15 struct adfs_bigdirheader *h;
16 struct adfs_bigdirtail *t;
18 unsigned int blk, size;
23 /* start off using fixed bh set - only alloc for big dirs */
24 dir->bh_fplus = &dir->bh[0];
26 block = __adfs_block_map(sb, id, 0);
28 adfs_error(sb, "dir object %X has a hole at offset 0", id);
32 dir->bh_fplus[0] = sb_bread(sb, block);
33 if (!dir->bh_fplus[0])
37 h = (struct adfs_bigdirheader *)dir->bh_fplus[0]->b_data;
38 size = le32_to_cpu(h->bigdirsize);
40 printk(KERN_WARNING "adfs: adfs_fplus_read:"
41 " directory header size %X\n"
42 " does not match directory size %X\n",
46 if (h->bigdirversion[0] != 0 || h->bigdirversion[1] != 0 ||
47 h->bigdirversion[2] != 0 || size & 2047 ||
48 h->bigdirstartname != cpu_to_le32(BIGDIRSTARTNAME)) {
49 printk(KERN_WARNING "adfs: dir object %X has"
50 " malformed dir header\n", id);
54 size >>= sb->s_blocksize_bits;
55 if (size > ARRAY_SIZE(dir->bh)) {
56 /* this directory is too big for fixed bh set, must allocate */
57 struct buffer_head **bh_fplus =
58 kcalloc(size, sizeof(struct buffer_head *),
62 adfs_error(sb, "not enough memory for"
63 " dir object %X (%d blocks)", id, size);
66 dir->bh_fplus = bh_fplus;
67 /* copy over the pointer to the block that we've already read */
68 dir->bh_fplus[0] = dir->bh[0];
71 for (blk = 1; blk < size; blk++) {
72 block = __adfs_block_map(sb, id, blk);
74 adfs_error(sb, "dir object %X has a hole at offset %d", id, blk);
78 dir->bh_fplus[blk] = sb_bread(sb, block);
79 if (!dir->bh_fplus[blk]) {
80 adfs_error(sb, "dir object %x failed read for offset %d, mapped block %lX",
88 t = (struct adfs_bigdirtail *)
89 (dir->bh_fplus[size - 1]->b_data + (sb->s_blocksize - 8));
91 if (t->bigdirendname != cpu_to_le32(BIGDIRENDNAME) ||
92 t->bigdirendmasseq != h->startmasseq ||
93 t->reserved[0] != 0 || t->reserved[1] != 0) {
94 printk(KERN_WARNING "adfs: dir object %X has "
95 "malformed dir end\n", id);
99 dir->parent_id = le32_to_cpu(h->bigdirparent);
105 for (i = 0; i < dir->nr_buffers; i++)
106 brelse(dir->bh_fplus[i]);
108 if (&dir->bh[0] != dir->bh_fplus)
109 kfree(dir->bh_fplus);
111 dir->bh_fplus = NULL;
120 adfs_fplus_setpos(struct adfs_dir *dir, unsigned int fpos)
122 struct adfs_bigdirheader *h =
123 (struct adfs_bigdirheader *) dir->bh_fplus[0]->b_data;
126 if (fpos <= le32_to_cpu(h->bigdirentries)) {
135 dir_memcpy(struct adfs_dir *dir, unsigned int offset, void *to, int len)
137 struct super_block *sb = dir->sb;
138 unsigned int buffer, partial, remainder;
140 buffer = offset >> sb->s_blocksize_bits;
141 offset &= sb->s_blocksize - 1;
143 partial = sb->s_blocksize - offset;
146 memcpy(to, dir->bh_fplus[buffer]->b_data + offset, len);
148 char *c = (char *)to;
150 remainder = len - partial;
153 dir->bh_fplus[buffer]->b_data + offset,
157 dir->bh_fplus[buffer + 1]->b_data,
163 adfs_fplus_getnext(struct adfs_dir *dir, struct object_info *obj)
165 struct adfs_bigdirheader *h =
166 (struct adfs_bigdirheader *) dir->bh_fplus[0]->b_data;
167 struct adfs_bigdirentry bde;
171 if (dir->pos >= le32_to_cpu(h->bigdirentries))
174 offset = offsetof(struct adfs_bigdirheader, bigdirname);
175 offset += ((le32_to_cpu(h->bigdirnamelen) + 4) & ~3);
176 offset += dir->pos * sizeof(struct adfs_bigdirentry);
178 dir_memcpy(dir, offset, &bde, sizeof(struct adfs_bigdirentry));
180 obj->loadaddr = le32_to_cpu(bde.bigdirload);
181 obj->execaddr = le32_to_cpu(bde.bigdirexec);
182 obj->size = le32_to_cpu(bde.bigdirlen);
183 obj->file_id = le32_to_cpu(bde.bigdirindaddr);
184 obj->attr = le32_to_cpu(bde.bigdirattr);
185 obj->name_len = le32_to_cpu(bde.bigdirobnamelen);
187 offset = offsetof(struct adfs_bigdirheader, bigdirname);
188 offset += ((le32_to_cpu(h->bigdirnamelen) + 4) & ~3);
189 offset += le32_to_cpu(h->bigdirentries) * sizeof(struct adfs_bigdirentry);
190 offset += le32_to_cpu(bde.bigdirobnameptr);
192 dir_memcpy(dir, offset, obj->name, obj->name_len);
193 adfs_object_fixup(dir, obj);
202 adfs_fplus_sync(struct adfs_dir *dir)
207 for (i = dir->nr_buffers - 1; i >= 0; i--) {
208 struct buffer_head *bh = dir->bh_fplus[i];
209 sync_dirty_buffer(bh);
210 if (buffer_req(bh) && !buffer_uptodate(bh))
218 adfs_fplus_free(struct adfs_dir *dir)
223 for (i = 0; i < dir->nr_buffers; i++)
224 brelse(dir->bh_fplus[i]);
226 if (&dir->bh[0] != dir->bh_fplus)
227 kfree(dir->bh_fplus);
229 dir->bh_fplus = NULL;
236 const struct adfs_dir_ops adfs_fplus_dir_ops = {
237 .read = adfs_fplus_read,
238 .setpos = adfs_fplus_setpos,
239 .getnext = adfs_fplus_getnext,
240 .sync = adfs_fplus_sync,
241 .free = adfs_fplus_free