Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 2 | * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3 | * Licensed under the GPL |
| 4 | * |
| 5 | * Ported the filesystem routines to 2.5. |
| 6 | * 2003-02-10 Petr Baudis <pasky@ucw.cz> |
| 7 | */ |
| 8 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 9 | #include <linux/fs.h> |
James Hogan | 2b3b9bb | 2013-03-27 10:47:13 +0000 | [diff] [blame] | 10 | #include <linux/magic.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | #include <linux/module.h> |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 12 | #include <linux/mm.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | #include <linux/pagemap.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 14 | #include <linux/statfs.h> |
Tejun Heo | 5a0e3ad | 2010-03-24 17:04:11 +0900 | [diff] [blame] | 15 | #include <linux/slab.h> |
Miklos Szeredi | dd2cc4d | 2008-02-08 04:21:43 -0800 | [diff] [blame] | 16 | #include <linux/seq_file.h> |
Jiri Kosina | 6966a97 | 2008-02-09 00:10:14 -0800 | [diff] [blame] | 17 | #include <linux/mount.h> |
Al Viro | d0352d3 | 2010-06-06 21:51:16 -0400 | [diff] [blame] | 18 | #include <linux/namei.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 19 | #include "hostfs.h" |
Al Viro | 37185b3 | 2012-10-08 03:27:32 +0100 | [diff] [blame] | 20 | #include <init.h> |
| 21 | #include <kern.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 22 | |
| 23 | struct hostfs_inode_info { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | int fd; |
Al Viro | aeb5d72 | 2008-09-02 15:28:45 -0400 | [diff] [blame] | 25 | fmode_t mode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | struct inode vfs_inode; |
Richard Weinberger | 69886e6 | 2015-02-27 22:55:20 +0100 | [diff] [blame] | 27 | struct mutex open_mutex; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 28 | }; |
| 29 | |
| 30 | static inline struct hostfs_inode_info *HOSTFS_I(struct inode *inode) |
| 31 | { |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 32 | return list_entry(inode, struct hostfs_inode_info, vfs_inode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 33 | } |
| 34 | |
Al Viro | 496ad9a | 2013-01-23 17:07:38 -0500 | [diff] [blame] | 35 | #define FILE_HOSTFS_I(file) HOSTFS_I(file_inode(file)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | /* Changed in hostfs_args before the kernel starts running */ |
Paolo 'Blaisorblade' Giarrusso | a6eb0be | 2007-03-07 20:41:08 -0800 | [diff] [blame] | 38 | static char *root_ino = ""; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | static int append = 0; |
| 40 | |
Arjan van de Ven | 92e1d5b | 2007-02-12 00:55:39 -0800 | [diff] [blame] | 41 | static const struct inode_operations hostfs_iops; |
| 42 | static const struct inode_operations hostfs_dir_iops; |
Al Viro | d0352d3 | 2010-06-06 21:51:16 -0400 | [diff] [blame] | 43 | static const struct inode_operations hostfs_link_iops; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 44 | |
| 45 | #ifndef MODULE |
| 46 | static int __init hostfs_args(char *options, int *add) |
| 47 | { |
| 48 | char *ptr; |
| 49 | |
| 50 | ptr = strchr(options, ','); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 51 | if (ptr != NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | *ptr++ = '\0'; |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 53 | if (*options != '\0') |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 54 | root_ino = options; |
| 55 | |
| 56 | options = ptr; |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 57 | while (options) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 58 | ptr = strchr(options, ','); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 59 | if (ptr != NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 60 | *ptr++ = '\0'; |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 61 | if (*options != '\0') { |
| 62 | if (!strcmp(options, "append")) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | append = 1; |
| 64 | else printf("hostfs_args - unsupported option - %s\n", |
| 65 | options); |
| 66 | } |
| 67 | options = ptr; |
| 68 | } |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 69 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 70 | } |
| 71 | |
| 72 | __uml_setup("hostfs=", hostfs_args, |
| 73 | "hostfs=<root dir>,<flags>,...\n" |
| 74 | " This is used to set hostfs parameters. The root directory argument\n" |
| 75 | " is used to confine all hostfs mounts to within the specified directory\n" |
| 76 | " tree on the host. If this isn't specified, then a user inside UML can\n" |
| 77 | " mount anything on the host that's accessible to the user that's running\n" |
| 78 | " it.\n" |
| 79 | " The only flag currently supported is 'append', which specifies that all\n" |
| 80 | " files opened by hostfs will be opened in append mode.\n\n" |
| 81 | ); |
| 82 | #endif |
| 83 | |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 84 | static char *__dentry_name(struct dentry *dentry, char *name) |
| 85 | { |
Nick Piggin | ec2447c | 2011-01-07 17:49:29 +1100 | [diff] [blame] | 86 | char *p = dentry_path_raw(dentry, name, PATH_MAX); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 87 | char *root; |
| 88 | size_t len; |
| 89 | |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 90 | root = dentry->d_sb->s_fs_info; |
| 91 | len = strlen(root); |
| 92 | if (IS_ERR(p)) { |
| 93 | __putname(name); |
| 94 | return NULL; |
| 95 | } |
Richard Weinberger | aad50b1 | 2015-03-03 23:41:52 +0100 | [diff] [blame] | 96 | |
| 97 | /* |
| 98 | * This function relies on the fact that dentry_path_raw() will place |
| 99 | * the path name at the end of the provided buffer. |
| 100 | */ |
| 101 | BUG_ON(p + strlen(p) + 1 != name + PATH_MAX); |
| 102 | |
Al Viro | 850a496 | 2010-08-18 06:18:57 -0400 | [diff] [blame] | 103 | strlcpy(name, root, PATH_MAX); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 104 | if (len > p - name) { |
| 105 | __putname(name); |
| 106 | return NULL; |
| 107 | } |
Richard Weinberger | c278e81 | 2015-03-03 23:42:25 +0100 | [diff] [blame] | 108 | |
| 109 | if (p > name + len) |
| 110 | strcpy(name + len, p); |
| 111 | |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 112 | return name; |
| 113 | } |
| 114 | |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 115 | static char *dentry_name(struct dentry *dentry) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 116 | { |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 117 | char *name = __getname(); |
| 118 | if (!name) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 119 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 120 | |
James Hogan | 9dcc5e8 | 2013-03-27 10:47:12 +0000 | [diff] [blame] | 121 | return __dentry_name(dentry, name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 122 | } |
| 123 | |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 124 | static char *inode_name(struct inode *ino) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 125 | { |
| 126 | struct dentry *dentry; |
Nick Piggin | ec2447c | 2011-01-07 17:49:29 +1100 | [diff] [blame] | 127 | char *name; |
| 128 | |
| 129 | dentry = d_find_alias(ino); |
| 130 | if (!dentry) |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 131 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 132 | |
Nick Piggin | ec2447c | 2011-01-07 17:49:29 +1100 | [diff] [blame] | 133 | name = dentry_name(dentry); |
| 134 | |
| 135 | dput(dentry); |
| 136 | |
| 137 | return name; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 138 | } |
| 139 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 140 | static char *follow_link(char *link) |
| 141 | { |
| 142 | int len, n; |
| 143 | char *name, *resolved, *end; |
| 144 | |
Richard Weinberger | 7c95099 | 2015-03-03 23:55:49 +0100 | [diff] [blame^] | 145 | name = __getname(); |
| 146 | if (!name) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 147 | n = -ENOMEM; |
Richard Weinberger | 7c95099 | 2015-03-03 23:55:49 +0100 | [diff] [blame^] | 148 | goto out_free; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 149 | } |
Richard Weinberger | 7c95099 | 2015-03-03 23:55:49 +0100 | [diff] [blame^] | 150 | |
| 151 | n = hostfs_do_readlink(link, name, PATH_MAX); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 152 | if (n < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 153 | goto out_free; |
Richard Weinberger | 7c95099 | 2015-03-03 23:55:49 +0100 | [diff] [blame^] | 154 | else if (n == PATH_MAX) { |
| 155 | n = -E2BIG; |
| 156 | goto out_free; |
| 157 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 159 | if (*name == '/') |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 160 | return name; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 161 | |
| 162 | end = strrchr(link, '/'); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 163 | if (end == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 164 | return name; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 165 | |
| 166 | *(end + 1) = '\0'; |
| 167 | len = strlen(link) + strlen(name) + 1; |
| 168 | |
| 169 | resolved = kmalloc(len, GFP_KERNEL); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 170 | if (resolved == NULL) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | n = -ENOMEM; |
| 172 | goto out_free; |
| 173 | } |
| 174 | |
| 175 | sprintf(resolved, "%s%s", link, name); |
Richard Weinberger | 7c95099 | 2015-03-03 23:55:49 +0100 | [diff] [blame^] | 176 | __putname(name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 177 | kfree(link); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 178 | return resolved; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 179 | |
| 180 | out_free: |
Richard Weinberger | 7c95099 | 2015-03-03 23:55:49 +0100 | [diff] [blame^] | 181 | __putname(name); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 182 | return ERR_PTR(n); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 183 | } |
| 184 | |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 185 | static struct inode *hostfs_iget(struct super_block *sb) |
| 186 | { |
Al Viro | 52b209f7 | 2010-06-06 18:43:19 -0400 | [diff] [blame] | 187 | struct inode *inode = new_inode(sb); |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 188 | if (!inode) |
| 189 | return ERR_PTR(-ENOMEM); |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 190 | return inode; |
| 191 | } |
| 192 | |
James Hogan | 9e443bc | 2013-11-14 21:15:13 +0000 | [diff] [blame] | 193 | static int hostfs_statfs(struct dentry *dentry, struct kstatfs *sf) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 194 | { |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 195 | /* |
| 196 | * do_statfs uses struct statfs64 internally, but the linux kernel |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 197 | * struct statfs still has 32-bit versions for most of these fields, |
| 198 | * so we convert them here |
| 199 | */ |
| 200 | int err; |
| 201 | long long f_blocks; |
| 202 | long long f_bfree; |
| 203 | long long f_bavail; |
| 204 | long long f_files; |
| 205 | long long f_ffree; |
| 206 | |
Al Viro | 601d2c3 | 2010-06-06 17:53:01 -0400 | [diff] [blame] | 207 | err = do_statfs(dentry->d_sb->s_fs_info, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 208 | &sf->f_bsize, &f_blocks, &f_bfree, &f_bavail, &f_files, |
| 209 | &f_ffree, &sf->f_fsid, sizeof(sf->f_fsid), |
Richard Weinberger | 1b627d5 | 2010-10-26 14:21:18 -0700 | [diff] [blame] | 210 | &sf->f_namelen); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 211 | if (err) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 212 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 213 | sf->f_blocks = f_blocks; |
| 214 | sf->f_bfree = f_bfree; |
| 215 | sf->f_bavail = f_bavail; |
| 216 | sf->f_files = f_files; |
| 217 | sf->f_ffree = f_ffree; |
| 218 | sf->f_type = HOSTFS_SUPER_MAGIC; |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 219 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 220 | } |
| 221 | |
| 222 | static struct inode *hostfs_alloc_inode(struct super_block *sb) |
| 223 | { |
| 224 | struct hostfs_inode_info *hi; |
| 225 | |
James Hogan | 371fdab | 2013-03-27 10:47:14 +0000 | [diff] [blame] | 226 | hi = kmalloc(sizeof(*hi), GFP_KERNEL); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 227 | if (hi == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 228 | return NULL; |
Al Viro | 601d2c3 | 2010-06-06 17:53:01 -0400 | [diff] [blame] | 229 | hi->fd = -1; |
James Hogan | 371fdab | 2013-03-27 10:47:14 +0000 | [diff] [blame] | 230 | hi->mode = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 231 | inode_init_once(&hi->vfs_inode); |
Richard Weinberger | 69886e6 | 2015-02-27 22:55:20 +0100 | [diff] [blame] | 232 | mutex_init(&hi->open_mutex); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 233 | return &hi->vfs_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 234 | } |
| 235 | |
Al Viro | e971a6d | 2010-06-06 15:16:17 -0400 | [diff] [blame] | 236 | static void hostfs_evict_inode(struct inode *inode) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 237 | { |
Johannes Weiner | 91b0abe | 2014-04-03 14:47:49 -0700 | [diff] [blame] | 238 | truncate_inode_pages_final(&inode->i_data); |
Jan Kara | dbd5768 | 2012-05-03 14:48:02 +0200 | [diff] [blame] | 239 | clear_inode(inode); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 240 | if (HOSTFS_I(inode)->fd != -1) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 241 | close_file(&HOSTFS_I(inode)->fd); |
| 242 | HOSTFS_I(inode)->fd = -1; |
| 243 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 244 | } |
| 245 | |
Nick Piggin | fa0d7e3d | 2011-01-07 17:49:49 +1100 | [diff] [blame] | 246 | static void hostfs_i_callback(struct rcu_head *head) |
| 247 | { |
| 248 | struct inode *inode = container_of(head, struct inode, i_rcu); |
Nick Piggin | fa0d7e3d | 2011-01-07 17:49:49 +1100 | [diff] [blame] | 249 | kfree(HOSTFS_I(inode)); |
| 250 | } |
| 251 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 252 | static void hostfs_destroy_inode(struct inode *inode) |
| 253 | { |
Nick Piggin | fa0d7e3d | 2011-01-07 17:49:49 +1100 | [diff] [blame] | 254 | call_rcu(&inode->i_rcu, hostfs_i_callback); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 255 | } |
| 256 | |
Al Viro | 34c80b1 | 2011-12-08 21:32:45 -0500 | [diff] [blame] | 257 | static int hostfs_show_options(struct seq_file *seq, struct dentry *root) |
Miklos Szeredi | dd2cc4d | 2008-02-08 04:21:43 -0800 | [diff] [blame] | 258 | { |
Al Viro | 34c80b1 | 2011-12-08 21:32:45 -0500 | [diff] [blame] | 259 | const char *root_path = root->d_sb->s_fs_info; |
Miklos Szeredi | dd2cc4d | 2008-02-08 04:21:43 -0800 | [diff] [blame] | 260 | size_t offset = strlen(root_ino) + 1; |
| 261 | |
| 262 | if (strlen(root_path) > offset) |
| 263 | seq_printf(seq, ",%s", root_path + offset); |
| 264 | |
| 265 | return 0; |
| 266 | } |
| 267 | |
Josef 'Jeff' Sipek | ee9b6d6 | 2007-02-12 00:55:41 -0800 | [diff] [blame] | 268 | static const struct super_operations hostfs_sbops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 269 | .alloc_inode = hostfs_alloc_inode, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 270 | .destroy_inode = hostfs_destroy_inode, |
Al Viro | e971a6d | 2010-06-06 15:16:17 -0400 | [diff] [blame] | 271 | .evict_inode = hostfs_evict_inode, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 272 | .statfs = hostfs_statfs, |
Miklos Szeredi | dd2cc4d | 2008-02-08 04:21:43 -0800 | [diff] [blame] | 273 | .show_options = hostfs_show_options, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 274 | }; |
| 275 | |
James Hogan | 9e443bc | 2013-11-14 21:15:13 +0000 | [diff] [blame] | 276 | static int hostfs_readdir(struct file *file, struct dir_context *ctx) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 277 | { |
| 278 | void *dir; |
| 279 | char *name; |
| 280 | unsigned long long next, ino; |
| 281 | int error, len; |
Geert Uytterhoeven | 3ee6bd8 | 2012-01-27 19:14:58 +0100 | [diff] [blame] | 282 | unsigned int type; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 283 | |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 284 | name = dentry_name(file->f_path.dentry); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 285 | if (name == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 286 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 287 | dir = open_dir(name, &error); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 288 | __putname(name); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 289 | if (dir == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 290 | return -error; |
Al Viro | 8e28bc7 | 2013-05-22 16:34:19 -0400 | [diff] [blame] | 291 | next = ctx->pos; |
Geert Uytterhoeven | 3ee6bd8 | 2012-01-27 19:14:58 +0100 | [diff] [blame] | 292 | while ((name = read_dir(dir, &next, &ino, &len, &type)) != NULL) { |
Al Viro | 8e28bc7 | 2013-05-22 16:34:19 -0400 | [diff] [blame] | 293 | if (!dir_emit(ctx, name, len, ino, type)) |
| 294 | break; |
| 295 | ctx->pos = next; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 296 | } |
| 297 | close_dir(dir); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 298 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 299 | } |
| 300 | |
Richard Weinberger | 4c6dcaf | 2015-03-02 00:09:33 +0100 | [diff] [blame] | 301 | static int hostfs_open(struct inode *ino, struct file *file) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 302 | { |
| 303 | char *name; |
Al Viro | aeb5d72 | 2008-09-02 15:28:45 -0400 | [diff] [blame] | 304 | fmode_t mode = 0; |
Al Viro | f8ad850 | 2010-06-06 23:49:18 -0400 | [diff] [blame] | 305 | int err; |
Al Viro | aeb5d72 | 2008-09-02 15:28:45 -0400 | [diff] [blame] | 306 | int r = 0, w = 0, fd; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 307 | |
| 308 | mode = file->f_mode & (FMODE_READ | FMODE_WRITE); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 309 | if ((mode & HOSTFS_I(ino)->mode) == mode) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 310 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 311 | |
Al Viro | f8ad850 | 2010-06-06 23:49:18 -0400 | [diff] [blame] | 312 | mode |= HOSTFS_I(ino)->mode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 313 | |
Al Viro | f8ad850 | 2010-06-06 23:49:18 -0400 | [diff] [blame] | 314 | retry: |
| 315 | if (mode & FMODE_READ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 316 | r = 1; |
Al Viro | f8ad850 | 2010-06-06 23:49:18 -0400 | [diff] [blame] | 317 | if (mode & FMODE_WRITE) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 318 | w = 1; |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 319 | if (w) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 320 | r = 1; |
| 321 | |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 322 | name = dentry_name(file->f_path.dentry); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 323 | if (name == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 324 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 325 | |
| 326 | fd = open_file(name, r, w, append); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 327 | __putname(name); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 328 | if (fd < 0) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 329 | return fd; |
Al Viro | f8ad850 | 2010-06-06 23:49:18 -0400 | [diff] [blame] | 330 | |
Richard Weinberger | 69886e6 | 2015-02-27 22:55:20 +0100 | [diff] [blame] | 331 | mutex_lock(&HOSTFS_I(ino)->open_mutex); |
Al Viro | f8ad850 | 2010-06-06 23:49:18 -0400 | [diff] [blame] | 332 | /* somebody else had handled it first? */ |
| 333 | if ((mode & HOSTFS_I(ino)->mode) == mode) { |
Richard Weinberger | 69886e6 | 2015-02-27 22:55:20 +0100 | [diff] [blame] | 334 | mutex_unlock(&HOSTFS_I(ino)->open_mutex); |
Richard Weinberger | af95565 | 2015-02-27 22:56:28 +0100 | [diff] [blame] | 335 | close_file(&fd); |
Al Viro | f8ad850 | 2010-06-06 23:49:18 -0400 | [diff] [blame] | 336 | return 0; |
| 337 | } |
| 338 | if ((mode | HOSTFS_I(ino)->mode) != mode) { |
| 339 | mode |= HOSTFS_I(ino)->mode; |
Richard Weinberger | 69886e6 | 2015-02-27 22:55:20 +0100 | [diff] [blame] | 340 | mutex_unlock(&HOSTFS_I(ino)->open_mutex); |
Al Viro | f8ad850 | 2010-06-06 23:49:18 -0400 | [diff] [blame] | 341 | close_file(&fd); |
| 342 | goto retry; |
| 343 | } |
| 344 | if (HOSTFS_I(ino)->fd == -1) { |
| 345 | HOSTFS_I(ino)->fd = fd; |
| 346 | } else { |
| 347 | err = replace_file(fd, HOSTFS_I(ino)->fd); |
| 348 | close_file(&fd); |
| 349 | if (err < 0) { |
Richard Weinberger | 69886e6 | 2015-02-27 22:55:20 +0100 | [diff] [blame] | 350 | mutex_unlock(&HOSTFS_I(ino)->open_mutex); |
Al Viro | f8ad850 | 2010-06-06 23:49:18 -0400 | [diff] [blame] | 351 | return err; |
| 352 | } |
| 353 | } |
| 354 | HOSTFS_I(ino)->mode = mode; |
Richard Weinberger | 69886e6 | 2015-02-27 22:55:20 +0100 | [diff] [blame] | 355 | mutex_unlock(&HOSTFS_I(ino)->open_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 356 | |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 357 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 358 | } |
| 359 | |
Richard Weinberger | 65984ff | 2013-08-04 17:23:51 +0000 | [diff] [blame] | 360 | static int hostfs_file_release(struct inode *inode, struct file *file) |
| 361 | { |
| 362 | filemap_write_and_wait(inode->i_mapping); |
| 363 | |
| 364 | return 0; |
| 365 | } |
| 366 | |
James Hogan | 9e443bc | 2013-11-14 21:15:13 +0000 | [diff] [blame] | 367 | static int hostfs_fsync(struct file *file, loff_t start, loff_t end, |
| 368 | int datasync) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 369 | { |
Josef Bacik | 02c24a8 | 2011-07-16 20:44:56 -0400 | [diff] [blame] | 370 | struct inode *inode = file->f_mapping->host; |
| 371 | int ret; |
| 372 | |
| 373 | ret = filemap_write_and_wait_range(inode->i_mapping, start, end); |
| 374 | if (ret) |
| 375 | return ret; |
| 376 | |
| 377 | mutex_lock(&inode->i_mutex); |
| 378 | ret = fsync_file(HOSTFS_I(inode)->fd, datasync); |
| 379 | mutex_unlock(&inode->i_mutex); |
| 380 | |
| 381 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 382 | } |
| 383 | |
Arjan van de Ven | 4b6f5d2 | 2006-03-28 01:56:42 -0800 | [diff] [blame] | 384 | static const struct file_operations hostfs_file_fops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 385 | .llseek = generic_file_llseek, |
Al Viro | aad4f8b | 2014-04-02 14:33:16 -0400 | [diff] [blame] | 386 | .read = new_sync_read, |
Jens Axboe | 5ffc4ef | 2007-06-01 11:49:19 +0200 | [diff] [blame] | 387 | .splice_read = generic_file_splice_read, |
Al Viro | aad4f8b | 2014-04-02 14:33:16 -0400 | [diff] [blame] | 388 | .read_iter = generic_file_read_iter, |
Al Viro | 8174202 | 2014-04-03 03:17:43 -0400 | [diff] [blame] | 389 | .write_iter = generic_file_write_iter, |
| 390 | .write = new_sync_write, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 391 | .mmap = generic_file_mmap, |
Richard Weinberger | 4c6dcaf | 2015-03-02 00:09:33 +0100 | [diff] [blame] | 392 | .open = hostfs_open, |
Richard Weinberger | 65984ff | 2013-08-04 17:23:51 +0000 | [diff] [blame] | 393 | .release = hostfs_file_release, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 394 | .fsync = hostfs_fsync, |
| 395 | }; |
| 396 | |
Arjan van de Ven | 4b6f5d2 | 2006-03-28 01:56:42 -0800 | [diff] [blame] | 397 | static const struct file_operations hostfs_dir_fops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 398 | .llseek = generic_file_llseek, |
Al Viro | 8e28bc7 | 2013-05-22 16:34:19 -0400 | [diff] [blame] | 399 | .iterate = hostfs_readdir, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 400 | .read = generic_read_dir, |
Richard Weinberger | 4c6dcaf | 2015-03-02 00:09:33 +0100 | [diff] [blame] | 401 | .open = hostfs_open, |
| 402 | .fsync = hostfs_fsync, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 403 | }; |
| 404 | |
James Hogan | 9e443bc | 2013-11-14 21:15:13 +0000 | [diff] [blame] | 405 | static int hostfs_writepage(struct page *page, struct writeback_control *wbc) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 406 | { |
| 407 | struct address_space *mapping = page->mapping; |
| 408 | struct inode *inode = mapping->host; |
| 409 | char *buffer; |
| 410 | unsigned long long base; |
| 411 | int count = PAGE_CACHE_SIZE; |
| 412 | int end_index = inode->i_size >> PAGE_CACHE_SHIFT; |
| 413 | int err; |
| 414 | |
| 415 | if (page->index >= end_index) |
| 416 | count = inode->i_size & (PAGE_CACHE_SIZE-1); |
| 417 | |
| 418 | buffer = kmap(page); |
| 419 | base = ((unsigned long long) page->index) << PAGE_CACHE_SHIFT; |
| 420 | |
| 421 | err = write_file(HOSTFS_I(inode)->fd, &base, buffer, count); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 422 | if (err != count) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 423 | ClearPageUptodate(page); |
| 424 | goto out; |
| 425 | } |
| 426 | |
| 427 | if (base > inode->i_size) |
| 428 | inode->i_size = base; |
| 429 | |
| 430 | if (PageError(page)) |
| 431 | ClearPageError(page); |
| 432 | err = 0; |
| 433 | |
| 434 | out: |
| 435 | kunmap(page); |
| 436 | |
| 437 | unlock_page(page); |
| 438 | return err; |
| 439 | } |
| 440 | |
James Hogan | 9e443bc | 2013-11-14 21:15:13 +0000 | [diff] [blame] | 441 | static int hostfs_readpage(struct file *file, struct page *page) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 442 | { |
| 443 | char *buffer; |
| 444 | long long start; |
Richard Weinberger | 41761dd | 2015-03-03 21:40:55 +0100 | [diff] [blame] | 445 | int bytes_read, ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 446 | |
| 447 | start = (long long) page->index << PAGE_CACHE_SHIFT; |
| 448 | buffer = kmap(page); |
Richard Weinberger | 41761dd | 2015-03-03 21:40:55 +0100 | [diff] [blame] | 449 | bytes_read = read_file(FILE_HOSTFS_I(file)->fd, &start, buffer, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 450 | PAGE_CACHE_SIZE); |
Richard Weinberger | 41761dd | 2015-03-03 21:40:55 +0100 | [diff] [blame] | 451 | if (bytes_read < 0) { |
| 452 | ret = bytes_read; |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 453 | goto out; |
Richard Weinberger | 41761dd | 2015-03-03 21:40:55 +0100 | [diff] [blame] | 454 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 455 | |
Richard Weinberger | 41761dd | 2015-03-03 21:40:55 +0100 | [diff] [blame] | 456 | memset(buffer + bytes_read, 0, PAGE_CACHE_SIZE - bytes_read); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 457 | |
| 458 | flush_dcache_page(page); |
| 459 | SetPageUptodate(page); |
| 460 | if (PageError(page)) ClearPageError(page); |
Richard Weinberger | 41761dd | 2015-03-03 21:40:55 +0100 | [diff] [blame] | 461 | ret = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 462 | out: |
| 463 | kunmap(page); |
| 464 | unlock_page(page); |
Richard Weinberger | 41761dd | 2015-03-03 21:40:55 +0100 | [diff] [blame] | 465 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 466 | } |
| 467 | |
James Hogan | 9e443bc | 2013-11-14 21:15:13 +0000 | [diff] [blame] | 468 | static int hostfs_write_begin(struct file *file, struct address_space *mapping, |
| 469 | loff_t pos, unsigned len, unsigned flags, |
| 470 | struct page **pagep, void **fsdata) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 471 | { |
Nick Piggin | ae361ff | 2007-10-16 01:25:17 -0700 | [diff] [blame] | 472 | pgoff_t index = pos >> PAGE_CACHE_SHIFT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 473 | |
Nick Piggin | 54566b2 | 2009-01-04 12:00:53 -0800 | [diff] [blame] | 474 | *pagep = grab_cache_page_write_begin(mapping, index, flags); |
Nick Piggin | ae361ff | 2007-10-16 01:25:17 -0700 | [diff] [blame] | 475 | if (!*pagep) |
| 476 | return -ENOMEM; |
| 477 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 478 | } |
| 479 | |
James Hogan | 9e443bc | 2013-11-14 21:15:13 +0000 | [diff] [blame] | 480 | static int hostfs_write_end(struct file *file, struct address_space *mapping, |
| 481 | loff_t pos, unsigned len, unsigned copied, |
| 482 | struct page *page, void *fsdata) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 483 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 484 | struct inode *inode = mapping->host; |
Nick Piggin | ae361ff | 2007-10-16 01:25:17 -0700 | [diff] [blame] | 485 | void *buffer; |
| 486 | unsigned from = pos & (PAGE_CACHE_SIZE - 1); |
| 487 | int err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 488 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 489 | buffer = kmap(page); |
Nick Piggin | ae361ff | 2007-10-16 01:25:17 -0700 | [diff] [blame] | 490 | err = write_file(FILE_HOSTFS_I(file)->fd, &pos, buffer + from, copied); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 491 | kunmap(page); |
Nick Piggin | ae361ff | 2007-10-16 01:25:17 -0700 | [diff] [blame] | 492 | |
| 493 | if (!PageUptodate(page) && err == PAGE_CACHE_SIZE) |
| 494 | SetPageUptodate(page); |
| 495 | |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 496 | /* |
| 497 | * If err > 0, write_file has added err to pos, so we are comparing |
Nick Piggin | ae361ff | 2007-10-16 01:25:17 -0700 | [diff] [blame] | 498 | * i_size against the last byte written. |
| 499 | */ |
| 500 | if (err > 0 && (pos > inode->i_size)) |
| 501 | inode->i_size = pos; |
| 502 | unlock_page(page); |
| 503 | page_cache_release(page); |
| 504 | |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 505 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 506 | } |
| 507 | |
Christoph Hellwig | f5e54d6 | 2006-06-28 04:26:44 -0700 | [diff] [blame] | 508 | static const struct address_space_operations hostfs_aops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 509 | .writepage = hostfs_writepage, |
| 510 | .readpage = hostfs_readpage, |
Paolo 'Blaisorblade' Giarrusso | ffa0aea | 2005-05-01 08:58:56 -0700 | [diff] [blame] | 511 | .set_page_dirty = __set_page_dirty_nobuffers, |
Nick Piggin | ae361ff | 2007-10-16 01:25:17 -0700 | [diff] [blame] | 512 | .write_begin = hostfs_write_begin, |
| 513 | .write_end = hostfs_write_end, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 514 | }; |
| 515 | |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 516 | static int read_name(struct inode *ino, char *name) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 517 | { |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 518 | dev_t rdev; |
| 519 | struct hostfs_stat st; |
| 520 | int err = stat_file(name, &st, -1); |
| 521 | if (err) |
| 522 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 523 | |
Al Viro | 5e2df28 | 2010-06-06 19:38:18 -0400 | [diff] [blame] | 524 | /* Reencode maj and min with the kernel encoding.*/ |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 525 | rdev = MKDEV(st.maj, st.min); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 526 | |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 527 | switch (st.mode & S_IFMT) { |
| 528 | case S_IFLNK: |
Al Viro | d0352d3 | 2010-06-06 21:51:16 -0400 | [diff] [blame] | 529 | ino->i_op = &hostfs_link_iops; |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 530 | break; |
| 531 | case S_IFDIR: |
| 532 | ino->i_op = &hostfs_dir_iops; |
| 533 | ino->i_fop = &hostfs_dir_fops; |
| 534 | break; |
| 535 | case S_IFCHR: |
| 536 | case S_IFBLK: |
| 537 | case S_IFIFO: |
| 538 | case S_IFSOCK: |
| 539 | init_special_inode(ino, st.mode & S_IFMT, rdev); |
| 540 | ino->i_op = &hostfs_iops; |
| 541 | break; |
Richard Weinberger | 2ad2dca | 2015-03-02 00:10:25 +0100 | [diff] [blame] | 542 | case S_IFREG: |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 543 | ino->i_op = &hostfs_iops; |
| 544 | ino->i_fop = &hostfs_file_fops; |
| 545 | ino->i_mapping->a_ops = &hostfs_aops; |
Richard Weinberger | 2ad2dca | 2015-03-02 00:10:25 +0100 | [diff] [blame] | 546 | break; |
| 547 | default: |
| 548 | return -EIO; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 549 | } |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 550 | |
| 551 | ino->i_ino = st.ino; |
| 552 | ino->i_mode = st.mode; |
Miklos Szeredi | bfe8684 | 2011-10-28 14:13:29 +0200 | [diff] [blame] | 553 | set_nlink(ino, st.nlink); |
Eric W. Biederman | 29f82ae | 2012-02-07 16:28:57 -0800 | [diff] [blame] | 554 | i_uid_write(ino, st.uid); |
| 555 | i_gid_write(ino, st.gid); |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 556 | ino->i_atime = st.atime; |
| 557 | ino->i_mtime = st.mtime; |
| 558 | ino->i_ctime = st.ctime; |
| 559 | ino->i_size = st.size; |
| 560 | ino->i_blocks = st.blocks; |
| 561 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 562 | } |
| 563 | |
James Hogan | 9e443bc | 2013-11-14 21:15:13 +0000 | [diff] [blame] | 564 | static int hostfs_create(struct inode *dir, struct dentry *dentry, umode_t mode, |
| 565 | bool excl) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 566 | { |
| 567 | struct inode *inode; |
| 568 | char *name; |
| 569 | int error, fd; |
| 570 | |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 571 | inode = hostfs_iget(dir->i_sb); |
| 572 | if (IS_ERR(inode)) { |
| 573 | error = PTR_ERR(inode); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 574 | goto out; |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 575 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 576 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 577 | error = -ENOMEM; |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 578 | name = dentry_name(dentry); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 579 | if (name == NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 580 | goto out_put; |
| 581 | |
| 582 | fd = file_create(name, |
| 583 | mode & S_IRUSR, mode & S_IWUSR, mode & S_IXUSR, |
| 584 | mode & S_IRGRP, mode & S_IWGRP, mode & S_IXGRP, |
| 585 | mode & S_IROTH, mode & S_IWOTH, mode & S_IXOTH); |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 586 | if (fd < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 587 | error = fd; |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 588 | else |
Al Viro | 5e2df28 | 2010-06-06 19:38:18 -0400 | [diff] [blame] | 589 | error = read_name(inode, name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 590 | |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 591 | __putname(name); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 592 | if (error) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 593 | goto out_put; |
| 594 | |
| 595 | HOSTFS_I(inode)->fd = fd; |
| 596 | HOSTFS_I(inode)->mode = FMODE_READ | FMODE_WRITE; |
| 597 | d_instantiate(dentry, inode); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 598 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 599 | |
| 600 | out_put: |
| 601 | iput(inode); |
| 602 | out: |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 603 | return error; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 604 | } |
| 605 | |
James Hogan | 9e443bc | 2013-11-14 21:15:13 +0000 | [diff] [blame] | 606 | static struct dentry *hostfs_lookup(struct inode *ino, struct dentry *dentry, |
| 607 | unsigned int flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 608 | { |
| 609 | struct inode *inode; |
| 610 | char *name; |
| 611 | int err; |
| 612 | |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 613 | inode = hostfs_iget(ino->i_sb); |
| 614 | if (IS_ERR(inode)) { |
| 615 | err = PTR_ERR(inode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 616 | goto out; |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 617 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 618 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 619 | err = -ENOMEM; |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 620 | name = dentry_name(dentry); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 621 | if (name == NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 622 | goto out_put; |
| 623 | |
| 624 | err = read_name(inode, name); |
Al Viro | 5e2df28 | 2010-06-06 19:38:18 -0400 | [diff] [blame] | 625 | |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 626 | __putname(name); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 627 | if (err == -ENOENT) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 628 | iput(inode); |
| 629 | inode = NULL; |
| 630 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 631 | else if (err) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 632 | goto out_put; |
| 633 | |
| 634 | d_add(dentry, inode); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 635 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 636 | |
| 637 | out_put: |
| 638 | iput(inode); |
| 639 | out: |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 640 | return ERR_PTR(err); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 641 | } |
| 642 | |
James Hogan | 9e443bc | 2013-11-14 21:15:13 +0000 | [diff] [blame] | 643 | static int hostfs_link(struct dentry *to, struct inode *ino, |
| 644 | struct dentry *from) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 645 | { |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 646 | char *from_name, *to_name; |
| 647 | int err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 648 | |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 649 | if ((from_name = dentry_name(from)) == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 650 | return -ENOMEM; |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 651 | to_name = dentry_name(to); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 652 | if (to_name == NULL) { |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 653 | __putname(from_name); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 654 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 655 | } |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 656 | err = link_file(to_name, from_name); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 657 | __putname(from_name); |
| 658 | __putname(to_name); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 659 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 660 | } |
| 661 | |
James Hogan | 9e443bc | 2013-11-14 21:15:13 +0000 | [diff] [blame] | 662 | static int hostfs_unlink(struct inode *ino, struct dentry *dentry) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 663 | { |
| 664 | char *file; |
| 665 | int err; |
| 666 | |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 667 | if (append) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 668 | return -EPERM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 669 | |
Al Viro | f8d7e18 | 2010-06-06 23:19:04 -0400 | [diff] [blame] | 670 | if ((file = dentry_name(dentry)) == NULL) |
| 671 | return -ENOMEM; |
| 672 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 673 | err = unlink_file(file); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 674 | __putname(file); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 675 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 676 | } |
| 677 | |
James Hogan | 9e443bc | 2013-11-14 21:15:13 +0000 | [diff] [blame] | 678 | static int hostfs_symlink(struct inode *ino, struct dentry *dentry, |
| 679 | const char *to) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 680 | { |
| 681 | char *file; |
| 682 | int err; |
| 683 | |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 684 | if ((file = dentry_name(dentry)) == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 685 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 686 | err = make_symlink(file, to); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 687 | __putname(file); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 688 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 689 | } |
| 690 | |
James Hogan | 9e443bc | 2013-11-14 21:15:13 +0000 | [diff] [blame] | 691 | static int hostfs_mkdir(struct inode *ino, struct dentry *dentry, umode_t mode) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 692 | { |
| 693 | char *file; |
| 694 | int err; |
| 695 | |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 696 | if ((file = dentry_name(dentry)) == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 697 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 698 | err = do_mkdir(file, mode); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 699 | __putname(file); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 700 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 701 | } |
| 702 | |
James Hogan | 9e443bc | 2013-11-14 21:15:13 +0000 | [diff] [blame] | 703 | static int hostfs_rmdir(struct inode *ino, struct dentry *dentry) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 704 | { |
| 705 | char *file; |
| 706 | int err; |
| 707 | |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 708 | if ((file = dentry_name(dentry)) == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 709 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 710 | err = do_rmdir(file); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 711 | __putname(file); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 712 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 713 | } |
| 714 | |
Al Viro | 1a67aaf | 2011-07-26 01:52:52 -0400 | [diff] [blame] | 715 | static int hostfs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 716 | { |
| 717 | struct inode *inode; |
| 718 | char *name; |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 719 | int err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 720 | |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 721 | inode = hostfs_iget(dir->i_sb); |
| 722 | if (IS_ERR(inode)) { |
| 723 | err = PTR_ERR(inode); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 724 | goto out; |
David Howells | 0a370e5 | 2008-02-07 00:15:50 -0800 | [diff] [blame] | 725 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 726 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 727 | err = -ENOMEM; |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 728 | name = dentry_name(dentry); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 729 | if (name == NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 730 | goto out_put; |
| 731 | |
| 732 | init_special_inode(inode, mode, dev); |
Johannes Stezenbach | 88f6cd0 | 2007-01-29 13:19:44 -0800 | [diff] [blame] | 733 | err = do_mknod(name, mode, MAJOR(dev), MINOR(dev)); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 734 | if (!err) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 735 | goto out_free; |
| 736 | |
| 737 | err = read_name(inode, name); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 738 | __putname(name); |
Al Viro | 5e2df28 | 2010-06-06 19:38:18 -0400 | [diff] [blame] | 739 | if (err) |
| 740 | goto out_put; |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 741 | if (err) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 742 | goto out_put; |
| 743 | |
| 744 | d_instantiate(dentry, inode); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 745 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 746 | |
| 747 | out_free: |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 748 | __putname(name); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 749 | out_put: |
| 750 | iput(inode); |
| 751 | out: |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 752 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 753 | } |
| 754 | |
Miklos Szeredi | 9a423bb | 2014-07-23 15:15:35 +0200 | [diff] [blame] | 755 | static int hostfs_rename2(struct inode *old_dir, struct dentry *old_dentry, |
| 756 | struct inode *new_dir, struct dentry *new_dentry, |
| 757 | unsigned int flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 758 | { |
Miklos Szeredi | 9a423bb | 2014-07-23 15:15:35 +0200 | [diff] [blame] | 759 | char *old_name, *new_name; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 760 | int err; |
| 761 | |
Miklos Szeredi | 9a423bb | 2014-07-23 15:15:35 +0200 | [diff] [blame] | 762 | if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE)) |
| 763 | return -EINVAL; |
| 764 | |
| 765 | old_name = dentry_name(old_dentry); |
| 766 | if (old_name == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 767 | return -ENOMEM; |
Miklos Szeredi | 9a423bb | 2014-07-23 15:15:35 +0200 | [diff] [blame] | 768 | new_name = dentry_name(new_dentry); |
| 769 | if (new_name == NULL) { |
| 770 | __putname(old_name); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 771 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 772 | } |
Miklos Szeredi | 9a423bb | 2014-07-23 15:15:35 +0200 | [diff] [blame] | 773 | if (!flags) |
| 774 | err = rename_file(old_name, new_name); |
| 775 | else |
| 776 | err = rename2_file(old_name, new_name, flags); |
| 777 | |
| 778 | __putname(old_name); |
| 779 | __putname(new_name); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 780 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 781 | } |
| 782 | |
James Hogan | 9e443bc | 2013-11-14 21:15:13 +0000 | [diff] [blame] | 783 | static int hostfs_permission(struct inode *ino, int desired) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 784 | { |
| 785 | char *name; |
| 786 | int r = 0, w = 0, x = 0, err; |
| 787 | |
Al Viro | 10556cb | 2011-06-20 19:28:19 -0400 | [diff] [blame] | 788 | if (desired & MAY_NOT_BLOCK) |
Nick Piggin | b74c79e | 2011-01-07 17:49:58 +1100 | [diff] [blame] | 789 | return -ECHILD; |
| 790 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 791 | if (desired & MAY_READ) r = 1; |
| 792 | if (desired & MAY_WRITE) w = 1; |
| 793 | if (desired & MAY_EXEC) x = 1; |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 794 | name = inode_name(ino); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 795 | if (name == NULL) |
| 796 | return -ENOMEM; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 797 | |
| 798 | if (S_ISCHR(ino->i_mode) || S_ISBLK(ino->i_mode) || |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 799 | S_ISFIFO(ino->i_mode) || S_ISSOCK(ino->i_mode)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 800 | err = 0; |
| 801 | else |
| 802 | err = access_file(name, r, w, x); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 803 | __putname(name); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 804 | if (!err) |
Al Viro | 2830ba7 | 2011-06-20 19:16:29 -0400 | [diff] [blame] | 805 | err = generic_permission(ino, desired); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 806 | return err; |
| 807 | } |
| 808 | |
James Hogan | 9e443bc | 2013-11-14 21:15:13 +0000 | [diff] [blame] | 809 | static int hostfs_setattr(struct dentry *dentry, struct iattr *attr) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 810 | { |
Christoph Hellwig | 1025774 | 2010-06-04 11:30:02 +0200 | [diff] [blame] | 811 | struct inode *inode = dentry->d_inode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 812 | struct hostfs_iattr attrs; |
| 813 | char *name; |
| 814 | int err; |
| 815 | |
Christoph Hellwig | 1025774 | 2010-06-04 11:30:02 +0200 | [diff] [blame] | 816 | int fd = HOSTFS_I(inode)->fd; |
Alberto Bertogli | 5822b7f | 2007-05-08 00:23:16 -0700 | [diff] [blame] | 817 | |
Christoph Hellwig | 1025774 | 2010-06-04 11:30:02 +0200 | [diff] [blame] | 818 | err = inode_change_ok(inode, attr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 819 | if (err) |
| 820 | return err; |
| 821 | |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 822 | if (append) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 823 | attr->ia_valid &= ~ATTR_SIZE; |
| 824 | |
| 825 | attrs.ia_valid = 0; |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 826 | if (attr->ia_valid & ATTR_MODE) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 827 | attrs.ia_valid |= HOSTFS_ATTR_MODE; |
| 828 | attrs.ia_mode = attr->ia_mode; |
| 829 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 830 | if (attr->ia_valid & ATTR_UID) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 831 | attrs.ia_valid |= HOSTFS_ATTR_UID; |
Eric W. Biederman | 29f82ae | 2012-02-07 16:28:57 -0800 | [diff] [blame] | 832 | attrs.ia_uid = from_kuid(&init_user_ns, attr->ia_uid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 833 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 834 | if (attr->ia_valid & ATTR_GID) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 835 | attrs.ia_valid |= HOSTFS_ATTR_GID; |
Eric W. Biederman | 29f82ae | 2012-02-07 16:28:57 -0800 | [diff] [blame] | 836 | attrs.ia_gid = from_kgid(&init_user_ns, attr->ia_gid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 837 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 838 | if (attr->ia_valid & ATTR_SIZE) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 839 | attrs.ia_valid |= HOSTFS_ATTR_SIZE; |
| 840 | attrs.ia_size = attr->ia_size; |
| 841 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 842 | if (attr->ia_valid & ATTR_ATIME) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 843 | attrs.ia_valid |= HOSTFS_ATTR_ATIME; |
| 844 | attrs.ia_atime = attr->ia_atime; |
| 845 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 846 | if (attr->ia_valid & ATTR_MTIME) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 847 | attrs.ia_valid |= HOSTFS_ATTR_MTIME; |
| 848 | attrs.ia_mtime = attr->ia_mtime; |
| 849 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 850 | if (attr->ia_valid & ATTR_CTIME) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 851 | attrs.ia_valid |= HOSTFS_ATTR_CTIME; |
| 852 | attrs.ia_ctime = attr->ia_ctime; |
| 853 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 854 | if (attr->ia_valid & ATTR_ATIME_SET) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 855 | attrs.ia_valid |= HOSTFS_ATTR_ATIME_SET; |
| 856 | } |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 857 | if (attr->ia_valid & ATTR_MTIME_SET) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 858 | attrs.ia_valid |= HOSTFS_ATTR_MTIME_SET; |
| 859 | } |
Al Viro | c532222 | 2010-06-06 20:42:10 -0400 | [diff] [blame] | 860 | name = dentry_name(dentry); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 861 | if (name == NULL) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 862 | return -ENOMEM; |
Alberto Bertogli | 5822b7f | 2007-05-08 00:23:16 -0700 | [diff] [blame] | 863 | err = set_attr(name, &attrs, fd); |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 864 | __putname(name); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 865 | if (err) |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 866 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 867 | |
Christoph Hellwig | 1025774 | 2010-06-04 11:30:02 +0200 | [diff] [blame] | 868 | if ((attr->ia_valid & ATTR_SIZE) && |
Marco Stornelli | bc07732 | 2012-10-20 12:02:59 +0200 | [diff] [blame] | 869 | attr->ia_size != i_size_read(inode)) |
Marco Stornelli | 3be2be0 | 2012-10-06 10:31:13 +0200 | [diff] [blame] | 870 | truncate_setsize(inode, attr->ia_size); |
Christoph Hellwig | 1025774 | 2010-06-04 11:30:02 +0200 | [diff] [blame] | 871 | |
| 872 | setattr_copy(inode, attr); |
| 873 | mark_inode_dirty(inode); |
| 874 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 875 | } |
| 876 | |
Arjan van de Ven | 92e1d5b | 2007-02-12 00:55:39 -0800 | [diff] [blame] | 877 | static const struct inode_operations hostfs_iops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 878 | .permission = hostfs_permission, |
| 879 | .setattr = hostfs_setattr, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 880 | }; |
| 881 | |
Arjan van de Ven | 92e1d5b | 2007-02-12 00:55:39 -0800 | [diff] [blame] | 882 | static const struct inode_operations hostfs_dir_iops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 883 | .create = hostfs_create, |
| 884 | .lookup = hostfs_lookup, |
| 885 | .link = hostfs_link, |
| 886 | .unlink = hostfs_unlink, |
| 887 | .symlink = hostfs_symlink, |
| 888 | .mkdir = hostfs_mkdir, |
| 889 | .rmdir = hostfs_rmdir, |
| 890 | .mknod = hostfs_mknod, |
Miklos Szeredi | 9a423bb | 2014-07-23 15:15:35 +0200 | [diff] [blame] | 891 | .rename2 = hostfs_rename2, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 892 | .permission = hostfs_permission, |
| 893 | .setattr = hostfs_setattr, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 894 | }; |
| 895 | |
Al Viro | d0352d3 | 2010-06-06 21:51:16 -0400 | [diff] [blame] | 896 | static void *hostfs_follow_link(struct dentry *dentry, struct nameidata *nd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 897 | { |
Al Viro | d0352d3 | 2010-06-06 21:51:16 -0400 | [diff] [blame] | 898 | char *link = __getname(); |
| 899 | if (link) { |
| 900 | char *path = dentry_name(dentry); |
| 901 | int err = -ENOMEM; |
| 902 | if (path) { |
Al Viro | 3b6036d | 2010-08-18 06:21:10 -0400 | [diff] [blame] | 903 | err = hostfs_do_readlink(path, link, PATH_MAX); |
Al Viro | d0352d3 | 2010-06-06 21:51:16 -0400 | [diff] [blame] | 904 | if (err == PATH_MAX) |
| 905 | err = -E2BIG; |
Al Viro | e919305 | 2010-06-06 23:16:34 -0400 | [diff] [blame] | 906 | __putname(path); |
Al Viro | d0352d3 | 2010-06-06 21:51:16 -0400 | [diff] [blame] | 907 | } |
| 908 | if (err < 0) { |
| 909 | __putname(link); |
| 910 | link = ERR_PTR(err); |
| 911 | } |
| 912 | } else { |
| 913 | link = ERR_PTR(-ENOMEM); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 914 | } |
Al Viro | d0352d3 | 2010-06-06 21:51:16 -0400 | [diff] [blame] | 915 | |
| 916 | nd_set_link(nd, link); |
| 917 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 918 | } |
| 919 | |
Al Viro | d0352d3 | 2010-06-06 21:51:16 -0400 | [diff] [blame] | 920 | static void hostfs_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie) |
| 921 | { |
| 922 | char *s = nd_get_link(nd); |
| 923 | if (!IS_ERR(s)) |
| 924 | __putname(s); |
| 925 | } |
| 926 | |
| 927 | static const struct inode_operations hostfs_link_iops = { |
| 928 | .readlink = generic_readlink, |
| 929 | .follow_link = hostfs_follow_link, |
| 930 | .put_link = hostfs_put_link, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 931 | }; |
| 932 | |
| 933 | static int hostfs_fill_sb_common(struct super_block *sb, void *d, int silent) |
| 934 | { |
| 935 | struct inode *root_inode; |
Paolo 'Blaisorblade' Giarrusso | 75e8def | 2007-03-29 01:20:33 -0700 | [diff] [blame] | 936 | char *host_root_path, *req_root = d; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 937 | int err; |
| 938 | |
| 939 | sb->s_blocksize = 1024; |
| 940 | sb->s_blocksize_bits = 10; |
| 941 | sb->s_magic = HOSTFS_SUPER_MAGIC; |
| 942 | sb->s_op = &hostfs_sbops; |
Al Viro | b26d4cd | 2013-10-25 18:47:37 -0400 | [diff] [blame] | 943 | sb->s_d_op = &simple_dentry_operations; |
Wolfgang Illmeyer | 752fa51 | 2009-06-30 11:41:44 -0700 | [diff] [blame] | 944 | sb->s_maxbytes = MAX_LFS_FILESIZE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 945 | |
Paolo 'Blaisorblade' Giarrusso | a6eb0be | 2007-03-07 20:41:08 -0800 | [diff] [blame] | 946 | /* NULL is printed as <NULL> by sprintf: avoid that. */ |
Paolo 'Blaisorblade' Giarrusso | 75e8def | 2007-03-29 01:20:33 -0700 | [diff] [blame] | 947 | if (req_root == NULL) |
| 948 | req_root = ""; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 949 | |
| 950 | err = -ENOMEM; |
Al Viro | 601d2c3 | 2010-06-06 17:53:01 -0400 | [diff] [blame] | 951 | sb->s_fs_info = host_root_path = |
| 952 | kmalloc(strlen(root_ino) + strlen(req_root) + 2, GFP_KERNEL); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 953 | if (host_root_path == NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 954 | goto out; |
| 955 | |
Paolo 'Blaisorblade' Giarrusso | 75e8def | 2007-03-29 01:20:33 -0700 | [diff] [blame] | 956 | sprintf(host_root_path, "%s/%s", root_ino, req_root); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 957 | |
Al Viro | 52b209f7 | 2010-06-06 18:43:19 -0400 | [diff] [blame] | 958 | root_inode = new_inode(sb); |
| 959 | if (!root_inode) |
Al Viro | 601d2c3 | 2010-06-06 17:53:01 -0400 | [diff] [blame] | 960 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 961 | |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 962 | err = read_name(root_inode, host_root_path); |
| 963 | if (err) |
| 964 | goto out_put; |
Al Viro | 52b209f7 | 2010-06-06 18:43:19 -0400 | [diff] [blame] | 965 | |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 966 | if (S_ISLNK(root_inode->i_mode)) { |
Al Viro | 52b209f7 | 2010-06-06 18:43:19 -0400 | [diff] [blame] | 967 | char *name = follow_link(host_root_path); |
| 968 | if (IS_ERR(name)) |
| 969 | err = PTR_ERR(name); |
| 970 | else |
| 971 | err = read_name(root_inode, name); |
| 972 | kfree(name); |
Al Viro | 4754b82 | 2010-06-06 20:33:12 -0400 | [diff] [blame] | 973 | if (err) |
| 974 | goto out_put; |
Al Viro | 52b209f7 | 2010-06-06 18:43:19 -0400 | [diff] [blame] | 975 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 976 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 977 | err = -ENOMEM; |
Al Viro | 48fde70 | 2012-01-08 22:15:13 -0500 | [diff] [blame] | 978 | sb->s_root = d_make_root(root_inode); |
Jeff Dike | 84b3db0 | 2007-10-16 01:27:13 -0700 | [diff] [blame] | 979 | if (sb->s_root == NULL) |
Al Viro | 48fde70 | 2012-01-08 22:15:13 -0500 | [diff] [blame] | 980 | goto out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 981 | |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 982 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 983 | |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 984 | out_put: |
| 985 | iput(root_inode); |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 986 | out: |
| 987 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 988 | } |
| 989 | |
Al Viro | 3c26ff6 | 2010-07-25 11:46:36 +0400 | [diff] [blame] | 990 | static struct dentry *hostfs_read_sb(struct file_system_type *type, |
David Howells | 454e239 | 2006-06-23 02:02:57 -0700 | [diff] [blame] | 991 | int flags, const char *dev_name, |
Al Viro | 3c26ff6 | 2010-07-25 11:46:36 +0400 | [diff] [blame] | 992 | void *data) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 993 | { |
Al Viro | 3c26ff6 | 2010-07-25 11:46:36 +0400 | [diff] [blame] | 994 | return mount_nodev(type, flags, data, hostfs_fill_sb_common); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 995 | } |
| 996 | |
Al Viro | 601d2c3 | 2010-06-06 17:53:01 -0400 | [diff] [blame] | 997 | static void hostfs_kill_sb(struct super_block *s) |
| 998 | { |
| 999 | kill_anon_super(s); |
| 1000 | kfree(s->s_fs_info); |
| 1001 | } |
| 1002 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1003 | static struct file_system_type hostfs_type = { |
| 1004 | .owner = THIS_MODULE, |
| 1005 | .name = "hostfs", |
Al Viro | 3c26ff6 | 2010-07-25 11:46:36 +0400 | [diff] [blame] | 1006 | .mount = hostfs_read_sb, |
Al Viro | 601d2c3 | 2010-06-06 17:53:01 -0400 | [diff] [blame] | 1007 | .kill_sb = hostfs_kill_sb, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1008 | .fs_flags = 0, |
| 1009 | }; |
Eric W. Biederman | 3e64fe5 | 2013-03-11 07:05:42 -0700 | [diff] [blame] | 1010 | MODULE_ALIAS_FS("hostfs"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1011 | |
| 1012 | static int __init init_hostfs(void) |
| 1013 | { |
Jeff Dike | f1adc05 | 2007-05-08 00:23:18 -0700 | [diff] [blame] | 1014 | return register_filesystem(&hostfs_type); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1015 | } |
| 1016 | |
| 1017 | static void __exit exit_hostfs(void) |
| 1018 | { |
| 1019 | unregister_filesystem(&hostfs_type); |
| 1020 | } |
| 1021 | |
| 1022 | module_init(init_hostfs) |
| 1023 | module_exit(exit_hostfs) |
| 1024 | MODULE_LICENSE("GPL"); |