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sysfs: fix sysfs_write_file for bin file
[karo-tx-linux.git] / fs / efs / dir.c
1 /*
2  * dir.c
3  *
4  * Copyright (c) 1999 Al Smith
5  */
6
7 #include <linux/buffer_head.h>
8 #include "efs.h"
9
10 static int efs_readdir(struct file *, struct dir_context *);
11
12 const struct file_operations efs_dir_operations = {
13         .llseek         = generic_file_llseek,
14         .read           = generic_read_dir,
15         .iterate        = efs_readdir,
16 };
17
18 const struct inode_operations efs_dir_inode_operations = {
19         .lookup         = efs_lookup,
20 };
21
22 static int efs_readdir(struct file *file, struct dir_context *ctx)
23 {
24         struct inode *inode = file_inode(file);
25         efs_block_t             block;
26         int                     slot;
27
28         if (inode->i_size & (EFS_DIRBSIZE-1))
29                 printk(KERN_WARNING "EFS: WARNING: readdir(): directory size not a multiple of EFS_DIRBSIZE\n");
30
31         /* work out where this entry can be found */
32         block = ctx->pos >> EFS_DIRBSIZE_BITS;
33
34         /* each block contains at most 256 slots */
35         slot  = ctx->pos & 0xff;
36
37         /* look at all blocks */
38         while (block < inode->i_blocks) {
39                 struct efs_dir          *dirblock;
40                 struct buffer_head *bh;
41
42                 /* read the dir block */
43                 bh = sb_bread(inode->i_sb, efs_bmap(inode, block));
44
45                 if (!bh) {
46                         printk(KERN_ERR "EFS: readdir(): failed to read dir block %d\n", block);
47                         break;
48                 }
49
50                 dirblock = (struct efs_dir *) bh->b_data; 
51
52                 if (be16_to_cpu(dirblock->magic) != EFS_DIRBLK_MAGIC) {
53                         printk(KERN_ERR "EFS: readdir(): invalid directory block\n");
54                         brelse(bh);
55                         break;
56                 }
57
58                 for (; slot < dirblock->slots; slot++) {
59                         struct efs_dentry *dirslot;
60                         efs_ino_t inodenum;
61                         const char *nameptr;
62                         int namelen;
63
64                         if (dirblock->space[slot] == 0)
65                                 continue;
66
67                         dirslot  = (struct efs_dentry *) (((char *) bh->b_data) + EFS_SLOTAT(dirblock, slot));
68
69                         inodenum = be32_to_cpu(dirslot->inode);
70                         namelen  = dirslot->namelen;
71                         nameptr  = dirslot->name;
72
73 #ifdef DEBUG
74                         printk(KERN_DEBUG "EFS: readdir(): block %d slot %d/%d: inode %u, name \"%s\", namelen %u\n", block, slot, dirblock->slots-1, inodenum, nameptr, namelen);
75 #endif
76                         if (!namelen)
77                                 continue;
78                         /* found the next entry */
79                         ctx->pos = (block << EFS_DIRBSIZE_BITS) | slot;
80
81                         /* sanity check */
82                         if (nameptr - (char *) dirblock + namelen > EFS_DIRBSIZE) {
83                                 printk(KERN_WARNING "EFS: directory entry %d exceeds directory block\n", slot);
84                                 continue;
85                         }
86
87                         /* copy filename and data in dirslot */
88                         if (!dir_emit(ctx, nameptr, namelen, inodenum, DT_UNKNOWN)) {
89                                 brelse(bh);
90                                 return 0;
91                         }
92                 }
93                 brelse(bh);
94
95                 slot = 0;
96                 block++;
97         }
98         ctx->pos = (block << EFS_DIRBSIZE_BITS) | slot;
99         return 0;
100 }
101