itree_v2.c
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#include <linux/buffer_head.h>
#include "minix.h"
enum {DIRECT = 7, DEPTH = 4}; /* Have triple indirect */
typedef u32 block_t; /* 32 bit, host order */
static inline unsigned long block_to_cpu(block_t n)
{
return n;
}
static inline block_t cpu_to_block(unsigned long n)
{
return n;
}
static inline block_t *i_data(struct inode *inode)
{
return (block_t *)minix_i(inode)->u.i2_data;
}
#define DIRCOUNT 7
#define INDIRCOUNT(sb) (1 << ((sb)->s_blocksize_bits - 2))
static int block_to_path(struct inode * inode, long block, int offsets[DEPTH])
{
int n = 0;
char b[BDEVNAME_SIZE];
struct super_block *sb = inode->i_sb;
if (block < 0) {
printk("MINIX-fs: block_to_path: block %ld < 0 on dev %s\n",
block, bdevname(sb->s_bdev, b));
} else if ((u64)block * (u64)sb->s_blocksize >=
minix_sb(sb)->s_max_size) {
if (printk_ratelimit())
printk("MINIX-fs: block_to_path: "
"block %ld too big on dev %s\n",
block, bdevname(sb->s_bdev, b));
} else if (block < DIRCOUNT) {
offsets[n++] = block;
} else if ((block -= DIRCOUNT) < INDIRCOUNT(sb)) {
offsets[n++] = DIRCOUNT;
offsets[n++] = block;
} else if ((block -= INDIRCOUNT(sb)) < INDIRCOUNT(sb) * INDIRCOUNT(sb)) {
offsets[n++] = DIRCOUNT + 1;
offsets[n++] = block / INDIRCOUNT(sb);
offsets[n++] = block % INDIRCOUNT(sb);
} else {
block -= INDIRCOUNT(sb) * INDIRCOUNT(sb);
offsets[n++] = DIRCOUNT + 2;
offsets[n++] = (block / INDIRCOUNT(sb)) / INDIRCOUNT(sb);
offsets[n++] = (block / INDIRCOUNT(sb)) % INDIRCOUNT(sb);
offsets[n++] = block % INDIRCOUNT(sb);
}
return n;
}
#include "itree_common.c"
int V2_minix_get_block(struct inode * inode, long block,
struct buffer_head *bh_result, int create)
{
return get_block(inode, block, bh_result, create);
}
void V2_minix_truncate(struct inode * inode)
{
truncate(inode);
}
unsigned V2_minix_blocks(loff_t size, struct super_block *sb)
{
return nblocks(size, sb);
}