1 #include <linux/buffer_head.h> 2 #include "minix.h" 3 4 enum {DIRECT = 7, DEPTH = 4}; /* Have triple indirect */ 5 6 typedef u32 block_t; /* 32 bit, host order */ 7 8 static inline unsigned long block_to_cpu(block_t n) 9 { 10 return n; 11 } 12 13 static inline block_t cpu_to_block(unsigned long n) 14 { 15 return n; 16 } 17 18 static inline block_t *i_data(struct inode *inode) 19 { 20 return (block_t *)minix_i(inode)->u.i2_data; 21 } 22 23 #define DIRCOUNT 7 24 #define INDIRCOUNT(sb) (1 << ((sb)->s_blocksize_bits - 2)) 25 26 static int block_to_path(struct inode * inode, long block, int offsets[DEPTH]) 27 { 28 int n = 0; 29 char b[BDEVNAME_SIZE]; 30 struct super_block *sb = inode->i_sb; 31 32 if (block < 0) { 33 printk("MINIX-fs: block_to_path: block %ld < 0 on dev %s\n", 34 block, bdevname(sb->s_bdev, b)); 35 } else if ((u64)block * (u64)sb->s_blocksize >= 36 minix_sb(sb)->s_max_size) { 37 if (printk_ratelimit()) 38 printk("MINIX-fs: block_to_path: " 39 "block %ld too big on dev %s\n", 40 block, bdevname(sb->s_bdev, b)); 41 } else if (block < DIRCOUNT) { 42 offsets[n++] = block; 43 } else if ((block -= DIRCOUNT) < INDIRCOUNT(sb)) { 44 offsets[n++] = DIRCOUNT; 45 offsets[n++] = block; 46 } else if ((block -= INDIRCOUNT(sb)) < INDIRCOUNT(sb) * INDIRCOUNT(sb)) { 47 offsets[n++] = DIRCOUNT + 1; 48 offsets[n++] = block / INDIRCOUNT(sb); 49 offsets[n++] = block % INDIRCOUNT(sb); 50 } else { 51 block -= INDIRCOUNT(sb) * INDIRCOUNT(sb); 52 offsets[n++] = DIRCOUNT + 2; 53 offsets[n++] = (block / INDIRCOUNT(sb)) / INDIRCOUNT(sb); 54 offsets[n++] = (block / INDIRCOUNT(sb)) % INDIRCOUNT(sb); 55 offsets[n++] = block % INDIRCOUNT(sb); 56 } 57 return n; 58 } 59 60 #include "itree_common.c" 61 62 int V2_minix_get_block(struct inode * inode, long block, 63 struct buffer_head *bh_result, int create) 64 { 65 return get_block(inode, block, bh_result, create); 66 } 67 68 void V2_minix_truncate(struct inode * inode) 69 { 70 truncate(inode); 71 } 72 73 unsigned V2_minix_blocks(loff_t size, struct super_block *sb) 74 { 75 return nblocks(size, sb); 76 } 77