xref: /OK3568_Linux_fs/kernel/fs/efs/file.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * file.c
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * Copyright (c) 1999 Al Smith
6*4882a593Smuzhiyun  *
7*4882a593Smuzhiyun  * Portions derived from work (c) 1995,1996 Christian Vogelgsang.
8*4882a593Smuzhiyun  */
9*4882a593Smuzhiyun 
10*4882a593Smuzhiyun #include <linux/buffer_head.h>
11*4882a593Smuzhiyun #include "efs.h"
12*4882a593Smuzhiyun 
efs_get_block(struct inode * inode,sector_t iblock,struct buffer_head * bh_result,int create)13*4882a593Smuzhiyun int efs_get_block(struct inode *inode, sector_t iblock,
14*4882a593Smuzhiyun 		  struct buffer_head *bh_result, int create)
15*4882a593Smuzhiyun {
16*4882a593Smuzhiyun 	int error = -EROFS;
17*4882a593Smuzhiyun 	long phys;
18*4882a593Smuzhiyun 
19*4882a593Smuzhiyun 	if (create)
20*4882a593Smuzhiyun 		return error;
21*4882a593Smuzhiyun 	if (iblock >= inode->i_blocks) {
22*4882a593Smuzhiyun #ifdef DEBUG
23*4882a593Smuzhiyun 		/*
24*4882a593Smuzhiyun 		 * i have no idea why this happens as often as it does
25*4882a593Smuzhiyun 		 */
26*4882a593Smuzhiyun 		pr_warn("%s(): block %d >= %ld (filesize %ld)\n",
27*4882a593Smuzhiyun 			__func__, block, inode->i_blocks, inode->i_size);
28*4882a593Smuzhiyun #endif
29*4882a593Smuzhiyun 		return 0;
30*4882a593Smuzhiyun 	}
31*4882a593Smuzhiyun 	phys = efs_map_block(inode, iblock);
32*4882a593Smuzhiyun 	if (phys)
33*4882a593Smuzhiyun 		map_bh(bh_result, inode->i_sb, phys);
34*4882a593Smuzhiyun 	return 0;
35*4882a593Smuzhiyun }
36*4882a593Smuzhiyun 
efs_bmap(struct inode * inode,efs_block_t block)37*4882a593Smuzhiyun int efs_bmap(struct inode *inode, efs_block_t block) {
38*4882a593Smuzhiyun 
39*4882a593Smuzhiyun 	if (block < 0) {
40*4882a593Smuzhiyun 		pr_warn("%s(): block < 0\n", __func__);
41*4882a593Smuzhiyun 		return 0;
42*4882a593Smuzhiyun 	}
43*4882a593Smuzhiyun 
44*4882a593Smuzhiyun 	/* are we about to read past the end of a file ? */
45*4882a593Smuzhiyun 	if (!(block < inode->i_blocks)) {
46*4882a593Smuzhiyun #ifdef DEBUG
47*4882a593Smuzhiyun 		/*
48*4882a593Smuzhiyun 		 * i have no idea why this happens as often as it does
49*4882a593Smuzhiyun 		 */
50*4882a593Smuzhiyun 		pr_warn("%s(): block %d >= %ld (filesize %ld)\n",
51*4882a593Smuzhiyun 			__func__, block, inode->i_blocks, inode->i_size);
52*4882a593Smuzhiyun #endif
53*4882a593Smuzhiyun 		return 0;
54*4882a593Smuzhiyun 	}
55*4882a593Smuzhiyun 
56*4882a593Smuzhiyun 	return efs_map_block(inode, block);
57*4882a593Smuzhiyun }
58