mm: fix exec activate_mm vs TLB shootdown and lazy tlb switching race
[linux/fpc-iii.git] / fs / affs / dir.c
bloba105e77df2c10b818bb4134b7fa6cf2075db34d4
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * linux/fs/affs/dir.c
5 * (c) 1996 Hans-Joachim Widmaier - Rewritten
7 * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem.
9 * (C) 1992 Eric Youngdale Modified for ISO 9660 filesystem.
11 * (C) 1991 Linus Torvalds - minix filesystem
13 * affs directory handling functions
17 #include "affs.h"
19 static int affs_readdir(struct file *, struct dir_context *);
21 const struct file_operations affs_dir_operations = {
22 .read = generic_read_dir,
23 .llseek = generic_file_llseek,
24 .iterate_shared = affs_readdir,
25 .fsync = affs_file_fsync,
29 * directories can handle most operations...
31 const struct inode_operations affs_dir_inode_operations = {
32 .create = affs_create,
33 .lookup = affs_lookup,
34 .link = affs_link,
35 .unlink = affs_unlink,
36 .symlink = affs_symlink,
37 .mkdir = affs_mkdir,
38 .rmdir = affs_rmdir,
39 .rename = affs_rename2,
40 .setattr = affs_notify_change,
43 static int
44 affs_readdir(struct file *file, struct dir_context *ctx)
46 struct inode *inode = file_inode(file);
47 struct super_block *sb = inode->i_sb;
48 struct buffer_head *dir_bh = NULL;
49 struct buffer_head *fh_bh = NULL;
50 unsigned char *name;
51 int namelen;
52 u32 i;
53 int hash_pos;
54 int chain_pos;
55 u32 ino;
56 int error = 0;
58 pr_debug("%s(ino=%lu,f_pos=%llx)\n", __func__, inode->i_ino, ctx->pos);
60 if (ctx->pos < 2) {
61 file->private_data = (void *)0;
62 if (!dir_emit_dots(file, ctx))
63 return 0;
66 affs_lock_dir(inode);
67 chain_pos = (ctx->pos - 2) & 0xffff;
68 hash_pos = (ctx->pos - 2) >> 16;
69 if (chain_pos == 0xffff) {
70 affs_warning(sb, "readdir", "More than 65535 entries in chain");
71 chain_pos = 0;
72 hash_pos++;
73 ctx->pos = ((hash_pos << 16) | chain_pos) + 2;
75 dir_bh = affs_bread(sb, inode->i_ino);
76 if (!dir_bh)
77 goto out_unlock_dir;
79 /* If the directory hasn't changed since the last call to readdir(),
80 * we can jump directly to where we left off.
82 ino = (u32)(long)file->private_data;
83 if (ino && file->f_version == inode->i_version) {
84 pr_debug("readdir() left off=%d\n", ino);
85 goto inside;
88 ino = be32_to_cpu(AFFS_HEAD(dir_bh)->table[hash_pos]);
89 for (i = 0; ino && i < chain_pos; i++) {
90 fh_bh = affs_bread(sb, ino);
91 if (!fh_bh) {
92 affs_error(sb, "readdir","Cannot read block %d", i);
93 error = -EIO;
94 goto out_brelse_dir;
96 ino = be32_to_cpu(AFFS_TAIL(sb, fh_bh)->hash_chain);
97 affs_brelse(fh_bh);
98 fh_bh = NULL;
100 if (ino)
101 goto inside;
102 hash_pos++;
104 for (; hash_pos < AFFS_SB(sb)->s_hashsize; hash_pos++) {
105 ino = be32_to_cpu(AFFS_HEAD(dir_bh)->table[hash_pos]);
106 if (!ino)
107 continue;
108 ctx->pos = (hash_pos << 16) + 2;
109 inside:
110 do {
111 fh_bh = affs_bread(sb, ino);
112 if (!fh_bh) {
113 affs_error(sb, "readdir",
114 "Cannot read block %d", ino);
115 break;
118 namelen = min(AFFS_TAIL(sb, fh_bh)->name[0],
119 (u8)AFFSNAMEMAX);
120 name = AFFS_TAIL(sb, fh_bh)->name + 1;
121 pr_debug("readdir(): dir_emit(\"%.*s\", ino=%u), hash=%d, f_pos=%llx\n",
122 namelen, name, ino, hash_pos, ctx->pos);
124 if (!dir_emit(ctx, name, namelen, ino, DT_UNKNOWN))
125 goto done;
126 ctx->pos++;
127 ino = be32_to_cpu(AFFS_TAIL(sb, fh_bh)->hash_chain);
128 affs_brelse(fh_bh);
129 fh_bh = NULL;
130 } while (ino);
132 done:
133 file->f_version = inode->i_version;
134 file->private_data = (void *)(long)ino;
135 affs_brelse(fh_bh);
137 out_brelse_dir:
138 affs_brelse(dir_bh);
140 out_unlock_dir:
141 affs_unlock_dir(inode);
142 return error;