1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/buffer_head.h> 3 #include "minix.h" 4 5 enum {DIRECT = 7, DEPTH = 4}; /* Have triple indirect */ 6 7 typedef u32 block_t; /* 32 bit, host order */ 8 9 static inline unsigned long block_to_cpu(block_t n) 10 { 11 return n; 12 } 13 14 static inline block_t cpu_to_block(unsigned long n) 15 { 16 return n; 17 } 18 19 static inline block_t *i_data(struct inode *inode) 20 { 21 return (block_t *)minix_i(inode)->u.i2_data; 22 } 23 24 #define DIRCOUNT 7 25 #define INDIRCOUNT(sb) (1 << ((sb)->s_blocksize_bits - 2)) 26 27 static int block_to_path(struct inode * inode, long block, int offsets[DEPTH]) 28 { 29 int n = 0; 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 %pg\n", 34 block, sb->s_bdev); 35 return 0; 36 } 37 if ((u64)block * (u64)sb->s_blocksize >= sb->s_maxbytes) 38 return 0; 39 40 if (block < DIRCOUNT) { 41 offsets[n++] = block; 42 } else if ((block -= DIRCOUNT) < INDIRCOUNT(sb)) { 43 offsets[n++] = DIRCOUNT; 44 offsets[n++] = block; 45 } else if ((block -= INDIRCOUNT(sb)) < INDIRCOUNT(sb) * INDIRCOUNT(sb)) { 46 offsets[n++] = DIRCOUNT + 1; 47 offsets[n++] = block / INDIRCOUNT(sb); 48 offsets[n++] = block % INDIRCOUNT(sb); 49 } else { 50 block -= INDIRCOUNT(sb) * INDIRCOUNT(sb); 51 offsets[n++] = DIRCOUNT + 2; 52 offsets[n++] = (block / INDIRCOUNT(sb)) / INDIRCOUNT(sb); 53 offsets[n++] = (block / INDIRCOUNT(sb)) % INDIRCOUNT(sb); 54 offsets[n++] = block % INDIRCOUNT(sb); 55 } 56 return n; 57 } 58 59 #include "itree_common.c" 60 61 int V2_minix_get_block(struct inode * inode, long block, 62 struct buffer_head *bh_result, int create) 63 { 64 return get_block(inode, block, bh_result, create); 65 } 66 67 void V2_minix_truncate(struct inode * inode) 68 { 69 truncate(inode); 70 } 71 72 unsigned V2_minix_blocks(loff_t size, struct super_block *sb) 73 { 74 return nblocks(size, sb); 75 } 76