diff options
Diffstat (limited to 'fs/adfs/dir_fplus.c')
| -rw-r--r-- | fs/adfs/dir_fplus.c | 179 |
1 files changed, 179 insertions, 0 deletions
diff --git a/fs/adfs/dir_fplus.c b/fs/adfs/dir_fplus.c new file mode 100644 index 00000000000..1ec644e32df --- /dev/null +++ b/fs/adfs/dir_fplus.c @@ -0,0 +1,179 @@ +/* + * linux/fs/adfs/dir_fplus.c + * + * Copyright (C) 1997-1999 Russell King + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/adfs_fs.h> +#include <linux/time.h> +#include <linux/stat.h> +#include <linux/spinlock.h> +#include <linux/buffer_head.h> +#include <linux/string.h> + +#include "adfs.h" +#include "dir_fplus.h" + +static int +adfs_fplus_read(struct super_block *sb, unsigned int id, unsigned int sz, struct adfs_dir *dir) +{ + struct adfs_bigdirheader *h; + struct adfs_bigdirtail *t; + unsigned long block; + unsigned int blk, size; + int i, ret = -EIO; + + dir->nr_buffers = 0; + + block = __adfs_block_map(sb, id, 0); + if (!block) { + adfs_error(sb, "dir object %X has a hole at offset 0", id); + goto out; + } + + dir->bh[0] = sb_bread(sb, block); + if (!dir->bh[0]) + goto out; + dir->nr_buffers += 1; + + h = (struct adfs_bigdirheader *)dir->bh[0]->b_data; + size = le32_to_cpu(h->bigdirsize); + if (size != sz) { + printk(KERN_WARNING "adfs: adfs_fplus_read: directory header size\n" + " does not match directory size\n"); + } + + if (h->bigdirversion[0] != 0 || h->bigdirversion[1] != 0 || + h->bigdirversion[2] != 0 || size & 2047 || + h->bigdirstartname != cpu_to_le32(BIGDIRSTARTNAME)) + goto out; + + size >>= sb->s_blocksize_bits; + for (blk = 1; blk < size; blk++) { + block = __adfs_block_map(sb, id, blk); + if (!block) { + adfs_error(sb, "dir object %X has a hole at offset %d", id, blk); + goto out; + } + + dir->bh[blk] = sb_bread(sb, block); + if (!dir->bh[blk]) + goto out; + dir->nr_buffers = blk; + } + + t = (struct adfs_bigdirtail *)(dir->bh[size - 1]->b_data + (sb->s_blocksize - 8)); + + if (t->bigdirendname != cpu_to_le32(BIGDIRENDNAME) || + t->bigdirendmasseq != h->startmasseq || + t->reserved[0] != 0 || t->reserved[1] != 0) + goto out; + + dir->parent_id = le32_to_cpu(h->bigdirparent); + dir->sb = sb; + return 0; +out: + for (i = 0; i < dir->nr_buffers; i++) + brelse(dir->bh[i]); + dir->sb = NULL; + return ret; +} + +static int +adfs_fplus_setpos(struct adfs_dir *dir, unsigned int fpos) +{ + struct adfs_bigdirheader *h = (struct adfs_bigdirheader *)dir->bh[0]->b_data; + int ret = -ENOENT; + + if (fpos <= le32_to_cpu(h->bigdirentries)) { + dir->pos = fpos; + ret = 0; + } + + return ret; +} + +static void +dir_memcpy(struct adfs_dir *dir, unsigned int offset, void *to, int len) +{ + struct super_block *sb = dir->sb; + unsigned int buffer, partial, remainder; + + buffer = offset >> sb->s_blocksize_bits; + offset &= sb->s_blocksize - 1; + + partial = sb->s_blocksize - offset; + + if (partial >= len) + memcpy(to, dir->bh[buffer]->b_data + offset, len); + else { + char *c = (char *)to; + + remainder = len - partial; + + memcpy(c, dir->bh[buffer]->b_data + offset, partial); + memcpy(c + partial, dir->bh[buffer + 1]->b_data, remainder); + } +} + +static int +adfs_fplus_getnext(struct adfs_dir *dir, struct object_info *obj) +{ + struct adfs_bigdirheader *h = (struct adfs_bigdirheader *)dir->bh[0]->b_data; + struct adfs_bigdirentry bde; + unsigned int offset; + int i, ret = -ENOENT; + + if (dir->pos >= le32_to_cpu(h->bigdirentries)) + goto out; + + offset = offsetof(struct adfs_bigdirheader, bigdirname); + offset += ((le32_to_cpu(h->bigdirnamelen) + 4) & ~3); + offset += dir->pos * sizeof(struct adfs_bigdirentry); + + dir_memcpy(dir, offset, &bde, sizeof(struct adfs_bigdirentry)); + + obj->loadaddr = le32_to_cpu(bde.bigdirload); + obj->execaddr = le32_to_cpu(bde.bigdirexec); + obj->size = le32_to_cpu(bde.bigdirlen); + obj->file_id = le32_to_cpu(bde.bigdirindaddr); + obj->attr = le32_to_cpu(bde.bigdirattr); + obj->name_len = le32_to_cpu(bde.bigdirobnamelen); + + offset = offsetof(struct adfs_bigdirheader, bigdirname); + offset += ((le32_to_cpu(h->bigdirnamelen) + 4) & ~3); + offset += le32_to_cpu(h->bigdirentries) * sizeof(struct adfs_bigdirentry); + offset += le32_to_cpu(bde.bigdirobnameptr); + + dir_memcpy(dir, offset, obj->name, obj->name_len); + for (i = 0; i < obj->name_len; i++) + if (obj->name[i] == '/') + obj->name[i] = '.'; + + dir->pos += 1; + ret = 0; +out: + return ret; +} + +static void +adfs_fplus_free(struct adfs_dir *dir) +{ + int i; + + for (i = 0; i < dir->nr_buffers; i++) + brelse(dir->bh[i]); + dir->sb = NULL; +} + +struct adfs_dir_ops adfs_fplus_dir_ops = { + .read = adfs_fplus_read, + .setpos = adfs_fplus_setpos, + .getnext = adfs_fplus_getnext, + .free = adfs_fplus_free +}; |