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1/*
2 * arch/s390/hypfs/inode.c
3 * Hypervisor filesystem for Linux on s390.
4 *
5 * Copyright IBM Corp. 2006, 2008
6 * Author(s): Michael Holzheu <holzheu@de.ibm.com>
7 */
8
9#define KMSG_COMPONENT "hypfs"
10#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11
12#include <linux/types.h>
13#include <linux/errno.h>
14#include <linux/fs.h>
15#include <linux/namei.h>
16#include <linux/vfs.h>
17#include <linux/slab.h>
18#include <linux/pagemap.h>
19#include <linux/time.h>
20#include <linux/parser.h>
21#include <linux/sysfs.h>
22#include <linux/module.h>
23#include <linux/seq_file.h>
24#include <linux/mount.h>
25#include <asm/ebcdic.h>
26#include "hypfs.h"
27
28#define HYPFS_MAGIC 0x687970 /* ASCII 'hyp' */
29#define TMP_SIZE 64 /* size of temporary buffers */
30
31static struct dentry *hypfs_create_update_file(struct super_block *sb,
32 struct dentry *dir);
33
34struct hypfs_sb_info {
35 uid_t uid; /* uid used for files and dirs */
36 gid_t gid; /* gid used for files and dirs */
37 struct dentry *update_file; /* file to trigger update */
38 time_t last_update; /* last update time in secs since 1970 */
39 struct mutex lock; /* lock to protect update process */
40};
41
42static const struct file_operations hypfs_file_ops;
43static struct file_system_type hypfs_type;
44static const struct super_operations hypfs_s_ops;
45
46/* start of list of all dentries, which have to be deleted on update */
47static struct dentry *hypfs_last_dentry;
48
49static void hypfs_update_update(struct super_block *sb)
50{
51 struct hypfs_sb_info *sb_info = sb->s_fs_info;
52 struct inode *inode = sb_info->update_file->d_inode;
53
54 sb_info->last_update = get_seconds();
55 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
56}
57
58/* directory tree removal functions */
59
60static void hypfs_add_dentry(struct dentry *dentry)
61{
62 dentry->d_fsdata = hypfs_last_dentry;
63 hypfs_last_dentry = dentry;
64}
65
66static inline int hypfs_positive(struct dentry *dentry)
67{
68 return dentry->d_inode && !d_unhashed(dentry);
69}
70
71static void hypfs_remove(struct dentry *dentry)
72{
73 struct dentry *parent;
74
75 parent = dentry->d_parent;
76 if (!parent || !parent->d_inode)
77 return;
78 mutex_lock(&parent->d_inode->i_mutex);
79 if (hypfs_positive(dentry)) {
80 if (S_ISDIR(dentry->d_inode->i_mode))
81 simple_rmdir(parent->d_inode, dentry);
82 else
83 simple_unlink(parent->d_inode, dentry);
84 }
85 d_delete(dentry);
86 dput(dentry);
87 mutex_unlock(&parent->d_inode->i_mutex);
88}
89
90static void hypfs_delete_tree(struct dentry *root)
91{
92 while (hypfs_last_dentry) {
93 struct dentry *next_dentry;
94 next_dentry = hypfs_last_dentry->d_fsdata;
95 hypfs_remove(hypfs_last_dentry);
96 hypfs_last_dentry = next_dentry;
97 }
98}
99
100static struct inode *hypfs_make_inode(struct super_block *sb, umode_t mode)
101{
102 struct inode *ret = new_inode(sb);
103
104 if (ret) {
105 struct hypfs_sb_info *hypfs_info = sb->s_fs_info;
106 ret->i_mode = mode;
107 ret->i_uid = hypfs_info->uid;
108 ret->i_gid = hypfs_info->gid;
109 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
110 if (S_ISDIR(mode))
111 set_nlink(ret, 2);
112 }
113 return ret;
114}
115
116static void hypfs_evict_inode(struct inode *inode)
117{
118 clear_inode(inode);
119 kfree(inode->i_private);
120}
121
122static int hypfs_open(struct inode *inode, struct file *filp)
123{
124 char *data = filp->f_path.dentry->d_inode->i_private;
125 struct hypfs_sb_info *fs_info;
126
127 if (filp->f_mode & FMODE_WRITE) {
128 if (!(inode->i_mode & S_IWUGO))
129 return -EACCES;
130 }
131 if (filp->f_mode & FMODE_READ) {
132 if (!(inode->i_mode & S_IRUGO))
133 return -EACCES;
134 }
135
136 fs_info = inode->i_sb->s_fs_info;
137 if(data) {
138 mutex_lock(&fs_info->lock);
139 filp->private_data = kstrdup(data, GFP_KERNEL);
140 if (!filp->private_data) {
141 mutex_unlock(&fs_info->lock);
142 return -ENOMEM;
143 }
144 mutex_unlock(&fs_info->lock);
145 }
146 return nonseekable_open(inode, filp);
147}
148
149static ssize_t hypfs_aio_read(struct kiocb *iocb, const struct iovec *iov,
150 unsigned long nr_segs, loff_t offset)
151{
152 char *data;
153 ssize_t ret;
154 struct file *filp = iocb->ki_filp;
155 /* XXX: temporary */
156 char __user *buf = iov[0].iov_base;
157 size_t count = iov[0].iov_len;
158
159 if (nr_segs != 1)
160 return -EINVAL;
161
162 data = filp->private_data;
163 ret = simple_read_from_buffer(buf, count, &offset, data, strlen(data));
164 if (ret <= 0)
165 return ret;
166
167 iocb->ki_pos += ret;
168 file_accessed(filp);
169
170 return ret;
171}
172static ssize_t hypfs_aio_write(struct kiocb *iocb, const struct iovec *iov,
173 unsigned long nr_segs, loff_t offset)
174{
175 int rc;
176 struct super_block *sb;
177 struct hypfs_sb_info *fs_info;
178 size_t count = iov_length(iov, nr_segs);
179
180 sb = iocb->ki_filp->f_path.dentry->d_inode->i_sb;
181 fs_info = sb->s_fs_info;
182 /*
183 * Currently we only allow one update per second for two reasons:
184 * 1. diag 204 is VERY expensive
185 * 2. If several processes do updates in parallel and then read the
186 * hypfs data, the likelihood of collisions is reduced, if we restrict
187 * the minimum update interval. A collision occurs, if during the
188 * data gathering of one process another process triggers an update
189 * If the first process wants to ensure consistent data, it has
190 * to restart data collection in this case.
191 */
192 mutex_lock(&fs_info->lock);
193 if (fs_info->last_update == get_seconds()) {
194 rc = -EBUSY;
195 goto out;
196 }
197 hypfs_delete_tree(sb->s_root);
198 if (MACHINE_IS_VM)
199 rc = hypfs_vm_create_files(sb, sb->s_root);
200 else
201 rc = hypfs_diag_create_files(sb, sb->s_root);
202 if (rc) {
203 pr_err("Updating the hypfs tree failed\n");
204 hypfs_delete_tree(sb->s_root);
205 goto out;
206 }
207 hypfs_update_update(sb);
208 rc = count;
209out:
210 mutex_unlock(&fs_info->lock);
211 return rc;
212}
213
214static int hypfs_release(struct inode *inode, struct file *filp)
215{
216 kfree(filp->private_data);
217 return 0;
218}
219
220enum { opt_uid, opt_gid, opt_err };
221
222static const match_table_t hypfs_tokens = {
223 {opt_uid, "uid=%u"},
224 {opt_gid, "gid=%u"},
225 {opt_err, NULL}
226};
227
228static int hypfs_parse_options(char *options, struct super_block *sb)
229{
230 char *str;
231 substring_t args[MAX_OPT_ARGS];
232
233 if (!options)
234 return 0;
235 while ((str = strsep(&options, ",")) != NULL) {
236 int token, option;
237 struct hypfs_sb_info *hypfs_info = sb->s_fs_info;
238
239 if (!*str)
240 continue;
241 token = match_token(str, hypfs_tokens, args);
242 switch (token) {
243 case opt_uid:
244 if (match_int(&args[0], &option))
245 return -EINVAL;
246 hypfs_info->uid = option;
247 break;
248 case opt_gid:
249 if (match_int(&args[0], &option))
250 return -EINVAL;
251 hypfs_info->gid = option;
252 break;
253 case opt_err:
254 default:
255 pr_err("%s is not a valid mount option\n", str);
256 return -EINVAL;
257 }
258 }
259 return 0;
260}
261
262static int hypfs_show_options(struct seq_file *s, struct dentry *root)
263{
264 struct hypfs_sb_info *hypfs_info = root->d_sb->s_fs_info;
265
266 seq_printf(s, ",uid=%u", hypfs_info->uid);
267 seq_printf(s, ",gid=%u", hypfs_info->gid);
268 return 0;
269}
270
271static int hypfs_fill_super(struct super_block *sb, void *data, int silent)
272{
273 struct inode *root_inode;
274 struct dentry *root_dentry;
275 int rc = 0;
276 struct hypfs_sb_info *sbi;
277
278 sbi = kzalloc(sizeof(struct hypfs_sb_info), GFP_KERNEL);
279 if (!sbi)
280 return -ENOMEM;
281 mutex_init(&sbi->lock);
282 sbi->uid = current_uid();
283 sbi->gid = current_gid();
284 sb->s_fs_info = sbi;
285 sb->s_blocksize = PAGE_CACHE_SIZE;
286 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
287 sb->s_magic = HYPFS_MAGIC;
288 sb->s_op = &hypfs_s_ops;
289 if (hypfs_parse_options(data, sb))
290 return -EINVAL;
291 root_inode = hypfs_make_inode(sb, S_IFDIR | 0755);
292 if (!root_inode)
293 return -ENOMEM;
294 root_inode->i_op = &simple_dir_inode_operations;
295 root_inode->i_fop = &simple_dir_operations;
296 sb->s_root = root_dentry = d_make_root(root_inode);
297 if (!root_dentry)
298 return -ENOMEM;
299 if (MACHINE_IS_VM)
300 rc = hypfs_vm_create_files(sb, root_dentry);
301 else
302 rc = hypfs_diag_create_files(sb, root_dentry);
303 if (rc)
304 return rc;
305 sbi->update_file = hypfs_create_update_file(sb, root_dentry);
306 if (IS_ERR(sbi->update_file))
307 return PTR_ERR(sbi->update_file);
308 hypfs_update_update(sb);
309 pr_info("Hypervisor filesystem mounted\n");
310 return 0;
311}
312
313static struct dentry *hypfs_mount(struct file_system_type *fst, int flags,
314 const char *devname, void *data)
315{
316 return mount_single(fst, flags, data, hypfs_fill_super);
317}
318
319static void hypfs_kill_super(struct super_block *sb)
320{
321 struct hypfs_sb_info *sb_info = sb->s_fs_info;
322
323 if (sb->s_root)
324 hypfs_delete_tree(sb->s_root);
325 if (sb_info->update_file)
326 hypfs_remove(sb_info->update_file);
327 kfree(sb->s_fs_info);
328 sb->s_fs_info = NULL;
329 kill_litter_super(sb);
330}
331
332static struct dentry *hypfs_create_file(struct super_block *sb,
333 struct dentry *parent, const char *name,
334 char *data, umode_t mode)
335{
336 struct dentry *dentry;
337 struct inode *inode;
338
339 mutex_lock(&parent->d_inode->i_mutex);
340 dentry = lookup_one_len(name, parent, strlen(name));
341 if (IS_ERR(dentry)) {
342 dentry = ERR_PTR(-ENOMEM);
343 goto fail;
344 }
345 inode = hypfs_make_inode(sb, mode);
346 if (!inode) {
347 dput(dentry);
348 dentry = ERR_PTR(-ENOMEM);
349 goto fail;
350 }
351 if (S_ISREG(mode)) {
352 inode->i_fop = &hypfs_file_ops;
353 if (data)
354 inode->i_size = strlen(data);
355 else
356 inode->i_size = 0;
357 } else if (S_ISDIR(mode)) {
358 inode->i_op = &simple_dir_inode_operations;
359 inode->i_fop = &simple_dir_operations;
360 inc_nlink(parent->d_inode);
361 } else
362 BUG();
363 inode->i_private = data;
364 d_instantiate(dentry, inode);
365 dget(dentry);
366fail:
367 mutex_unlock(&parent->d_inode->i_mutex);
368 return dentry;
369}
370
371struct dentry *hypfs_mkdir(struct super_block *sb, struct dentry *parent,
372 const char *name)
373{
374 struct dentry *dentry;
375
376 dentry = hypfs_create_file(sb, parent, name, NULL, S_IFDIR | DIR_MODE);
377 if (IS_ERR(dentry))
378 return dentry;
379 hypfs_add_dentry(dentry);
380 return dentry;
381}
382
383static struct dentry *hypfs_create_update_file(struct super_block *sb,
384 struct dentry *dir)
385{
386 struct dentry *dentry;
387
388 dentry = hypfs_create_file(sb, dir, "update", NULL,
389 S_IFREG | UPDATE_FILE_MODE);
390 /*
391 * We do not put the update file on the 'delete' list with
392 * hypfs_add_dentry(), since it should not be removed when the tree
393 * is updated.
394 */
395 return dentry;
396}
397
398struct dentry *hypfs_create_u64(struct super_block *sb, struct dentry *dir,
399 const char *name, __u64 value)
400{
401 char *buffer;
402 char tmp[TMP_SIZE];
403 struct dentry *dentry;
404
405 snprintf(tmp, TMP_SIZE, "%llu\n", (unsigned long long int)value);
406 buffer = kstrdup(tmp, GFP_KERNEL);
407 if (!buffer)
408 return ERR_PTR(-ENOMEM);
409 dentry =
410 hypfs_create_file(sb, dir, name, buffer, S_IFREG | REG_FILE_MODE);
411 if (IS_ERR(dentry)) {
412 kfree(buffer);
413 return ERR_PTR(-ENOMEM);
414 }
415 hypfs_add_dentry(dentry);
416 return dentry;
417}
418
419struct dentry *hypfs_create_str(struct super_block *sb, struct dentry *dir,
420 const char *name, char *string)
421{
422 char *buffer;
423 struct dentry *dentry;
424
425 buffer = kmalloc(strlen(string) + 2, GFP_KERNEL);
426 if (!buffer)
427 return ERR_PTR(-ENOMEM);
428 sprintf(buffer, "%s\n", string);
429 dentry =
430 hypfs_create_file(sb, dir, name, buffer, S_IFREG | REG_FILE_MODE);
431 if (IS_ERR(dentry)) {
432 kfree(buffer);
433 return ERR_PTR(-ENOMEM);
434 }
435 hypfs_add_dentry(dentry);
436 return dentry;
437}
438
439static const struct file_operations hypfs_file_ops = {
440 .open = hypfs_open,
441 .release = hypfs_release,
442 .read = do_sync_read,
443 .write = do_sync_write,
444 .aio_read = hypfs_aio_read,
445 .aio_write = hypfs_aio_write,
446 .llseek = no_llseek,
447};
448
449static struct file_system_type hypfs_type = {
450 .owner = THIS_MODULE,
451 .name = "s390_hypfs",
452 .mount = hypfs_mount,
453 .kill_sb = hypfs_kill_super
454};
455
456static const struct super_operations hypfs_s_ops = {
457 .statfs = simple_statfs,
458 .evict_inode = hypfs_evict_inode,
459 .show_options = hypfs_show_options,
460};
461
462static struct kobject *s390_kobj;
463
464static int __init hypfs_init(void)
465{
466 int rc;
467
468 rc = hypfs_dbfs_init();
469 if (rc)
470 return rc;
471 if (hypfs_diag_init()) {
472 rc = -ENODATA;
473 goto fail_dbfs_exit;
474 }
475 if (hypfs_vm_init()) {
476 rc = -ENODATA;
477 goto fail_hypfs_diag_exit;
478 }
479 s390_kobj = kobject_create_and_add("s390", hypervisor_kobj);
480 if (!s390_kobj) {
481 rc = -ENOMEM;
482 goto fail_hypfs_vm_exit;
483 }
484 rc = register_filesystem(&hypfs_type);
485 if (rc)
486 goto fail_filesystem;
487 return 0;
488
489fail_filesystem:
490 kobject_put(s390_kobj);
491fail_hypfs_vm_exit:
492 hypfs_vm_exit();
493fail_hypfs_diag_exit:
494 hypfs_diag_exit();
495fail_dbfs_exit:
496 hypfs_dbfs_exit();
497 pr_err("Initialization of hypfs failed with rc=%i\n", rc);
498 return rc;
499}
500
501static void __exit hypfs_exit(void)
502{
503 hypfs_diag_exit();
504 hypfs_vm_exit();
505 hypfs_dbfs_exit();
506 unregister_filesystem(&hypfs_type);
507 kobject_put(s390_kobj);
508}
509
510module_init(hypfs_init)
511module_exit(hypfs_exit)
512
513MODULE_LICENSE("GPL");
514MODULE_AUTHOR("Michael Holzheu <holzheu@de.ibm.com>");
515MODULE_DESCRIPTION("s390 Hypervisor Filesystem");
1/*
2 * Hypervisor filesystem for Linux on s390.
3 *
4 * Copyright IBM Corp. 2006, 2008
5 * Author(s): Michael Holzheu <holzheu@de.ibm.com>
6 */
7
8#define KMSG_COMPONENT "hypfs"
9#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
10
11#include <linux/types.h>
12#include <linux/errno.h>
13#include <linux/fs.h>
14#include <linux/namei.h>
15#include <linux/vfs.h>
16#include <linux/slab.h>
17#include <linux/pagemap.h>
18#include <linux/time.h>
19#include <linux/parser.h>
20#include <linux/sysfs.h>
21#include <linux/module.h>
22#include <linux/seq_file.h>
23#include <linux/mount.h>
24#include <linux/aio.h>
25#include <asm/ebcdic.h>
26#include "hypfs.h"
27
28#define HYPFS_MAGIC 0x687970 /* ASCII 'hyp' */
29#define TMP_SIZE 64 /* size of temporary buffers */
30
31static struct dentry *hypfs_create_update_file(struct dentry *dir);
32
33struct hypfs_sb_info {
34 kuid_t uid; /* uid used for files and dirs */
35 kgid_t gid; /* gid used for files and dirs */
36 struct dentry *update_file; /* file to trigger update */
37 time_t last_update; /* last update time in secs since 1970 */
38 struct mutex lock; /* lock to protect update process */
39};
40
41static const struct file_operations hypfs_file_ops;
42static struct file_system_type hypfs_type;
43static const struct super_operations hypfs_s_ops;
44
45/* start of list of all dentries, which have to be deleted on update */
46static struct dentry *hypfs_last_dentry;
47
48static void hypfs_update_update(struct super_block *sb)
49{
50 struct hypfs_sb_info *sb_info = sb->s_fs_info;
51 struct inode *inode = sb_info->update_file->d_inode;
52
53 sb_info->last_update = get_seconds();
54 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
55}
56
57/* directory tree removal functions */
58
59static void hypfs_add_dentry(struct dentry *dentry)
60{
61 dentry->d_fsdata = hypfs_last_dentry;
62 hypfs_last_dentry = dentry;
63}
64
65static inline int hypfs_positive(struct dentry *dentry)
66{
67 return dentry->d_inode && !d_unhashed(dentry);
68}
69
70static void hypfs_remove(struct dentry *dentry)
71{
72 struct dentry *parent;
73
74 parent = dentry->d_parent;
75 mutex_lock(&parent->d_inode->i_mutex);
76 if (hypfs_positive(dentry)) {
77 if (S_ISDIR(dentry->d_inode->i_mode))
78 simple_rmdir(parent->d_inode, dentry);
79 else
80 simple_unlink(parent->d_inode, dentry);
81 }
82 d_delete(dentry);
83 dput(dentry);
84 mutex_unlock(&parent->d_inode->i_mutex);
85}
86
87static void hypfs_delete_tree(struct dentry *root)
88{
89 while (hypfs_last_dentry) {
90 struct dentry *next_dentry;
91 next_dentry = hypfs_last_dentry->d_fsdata;
92 hypfs_remove(hypfs_last_dentry);
93 hypfs_last_dentry = next_dentry;
94 }
95}
96
97static struct inode *hypfs_make_inode(struct super_block *sb, umode_t mode)
98{
99 struct inode *ret = new_inode(sb);
100
101 if (ret) {
102 struct hypfs_sb_info *hypfs_info = sb->s_fs_info;
103 ret->i_ino = get_next_ino();
104 ret->i_mode = mode;
105 ret->i_uid = hypfs_info->uid;
106 ret->i_gid = hypfs_info->gid;
107 ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
108 if (S_ISDIR(mode))
109 set_nlink(ret, 2);
110 }
111 return ret;
112}
113
114static void hypfs_evict_inode(struct inode *inode)
115{
116 clear_inode(inode);
117 kfree(inode->i_private);
118}
119
120static int hypfs_open(struct inode *inode, struct file *filp)
121{
122 char *data = file_inode(filp)->i_private;
123 struct hypfs_sb_info *fs_info;
124
125 if (filp->f_mode & FMODE_WRITE) {
126 if (!(inode->i_mode & S_IWUGO))
127 return -EACCES;
128 }
129 if (filp->f_mode & FMODE_READ) {
130 if (!(inode->i_mode & S_IRUGO))
131 return -EACCES;
132 }
133
134 fs_info = inode->i_sb->s_fs_info;
135 if(data) {
136 mutex_lock(&fs_info->lock);
137 filp->private_data = kstrdup(data, GFP_KERNEL);
138 if (!filp->private_data) {
139 mutex_unlock(&fs_info->lock);
140 return -ENOMEM;
141 }
142 mutex_unlock(&fs_info->lock);
143 }
144 return nonseekable_open(inode, filp);
145}
146
147static ssize_t hypfs_aio_read(struct kiocb *iocb, const struct iovec *iov,
148 unsigned long nr_segs, loff_t offset)
149{
150 char *data;
151 ssize_t ret;
152 struct file *filp = iocb->ki_filp;
153 /* XXX: temporary */
154 char __user *buf = iov[0].iov_base;
155 size_t count = iov[0].iov_len;
156
157 if (nr_segs != 1)
158 return -EINVAL;
159
160 data = filp->private_data;
161 ret = simple_read_from_buffer(buf, count, &offset, data, strlen(data));
162 if (ret <= 0)
163 return ret;
164
165 iocb->ki_pos += ret;
166 file_accessed(filp);
167
168 return ret;
169}
170static ssize_t hypfs_aio_write(struct kiocb *iocb, const struct iovec *iov,
171 unsigned long nr_segs, loff_t offset)
172{
173 int rc;
174 struct super_block *sb = file_inode(iocb->ki_filp)->i_sb;
175 struct hypfs_sb_info *fs_info = sb->s_fs_info;
176 size_t count = iov_length(iov, nr_segs);
177
178 /*
179 * Currently we only allow one update per second for two reasons:
180 * 1. diag 204 is VERY expensive
181 * 2. If several processes do updates in parallel and then read the
182 * hypfs data, the likelihood of collisions is reduced, if we restrict
183 * the minimum update interval. A collision occurs, if during the
184 * data gathering of one process another process triggers an update
185 * If the first process wants to ensure consistent data, it has
186 * to restart data collection in this case.
187 */
188 mutex_lock(&fs_info->lock);
189 if (fs_info->last_update == get_seconds()) {
190 rc = -EBUSY;
191 goto out;
192 }
193 hypfs_delete_tree(sb->s_root);
194 if (MACHINE_IS_VM)
195 rc = hypfs_vm_create_files(sb->s_root);
196 else
197 rc = hypfs_diag_create_files(sb->s_root);
198 if (rc) {
199 pr_err("Updating the hypfs tree failed\n");
200 hypfs_delete_tree(sb->s_root);
201 goto out;
202 }
203 hypfs_update_update(sb);
204 rc = count;
205out:
206 mutex_unlock(&fs_info->lock);
207 return rc;
208}
209
210static int hypfs_release(struct inode *inode, struct file *filp)
211{
212 kfree(filp->private_data);
213 return 0;
214}
215
216enum { opt_uid, opt_gid, opt_err };
217
218static const match_table_t hypfs_tokens = {
219 {opt_uid, "uid=%u"},
220 {opt_gid, "gid=%u"},
221 {opt_err, NULL}
222};
223
224static int hypfs_parse_options(char *options, struct super_block *sb)
225{
226 char *str;
227 substring_t args[MAX_OPT_ARGS];
228 kuid_t uid;
229 kgid_t gid;
230
231 if (!options)
232 return 0;
233 while ((str = strsep(&options, ",")) != NULL) {
234 int token, option;
235 struct hypfs_sb_info *hypfs_info = sb->s_fs_info;
236
237 if (!*str)
238 continue;
239 token = match_token(str, hypfs_tokens, args);
240 switch (token) {
241 case opt_uid:
242 if (match_int(&args[0], &option))
243 return -EINVAL;
244 uid = make_kuid(current_user_ns(), option);
245 if (!uid_valid(uid))
246 return -EINVAL;
247 hypfs_info->uid = uid;
248 break;
249 case opt_gid:
250 if (match_int(&args[0], &option))
251 return -EINVAL;
252 gid = make_kgid(current_user_ns(), option);
253 if (!gid_valid(gid))
254 return -EINVAL;
255 hypfs_info->gid = gid;
256 break;
257 case opt_err:
258 default:
259 pr_err("%s is not a valid mount option\n", str);
260 return -EINVAL;
261 }
262 }
263 return 0;
264}
265
266static int hypfs_show_options(struct seq_file *s, struct dentry *root)
267{
268 struct hypfs_sb_info *hypfs_info = root->d_sb->s_fs_info;
269
270 seq_printf(s, ",uid=%u", from_kuid_munged(&init_user_ns, hypfs_info->uid));
271 seq_printf(s, ",gid=%u", from_kgid_munged(&init_user_ns, hypfs_info->gid));
272 return 0;
273}
274
275static int hypfs_fill_super(struct super_block *sb, void *data, int silent)
276{
277 struct inode *root_inode;
278 struct dentry *root_dentry;
279 int rc = 0;
280 struct hypfs_sb_info *sbi;
281
282 sbi = kzalloc(sizeof(struct hypfs_sb_info), GFP_KERNEL);
283 if (!sbi)
284 return -ENOMEM;
285 mutex_init(&sbi->lock);
286 sbi->uid = current_uid();
287 sbi->gid = current_gid();
288 sb->s_fs_info = sbi;
289 sb->s_blocksize = PAGE_CACHE_SIZE;
290 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
291 sb->s_magic = HYPFS_MAGIC;
292 sb->s_op = &hypfs_s_ops;
293 if (hypfs_parse_options(data, sb))
294 return -EINVAL;
295 root_inode = hypfs_make_inode(sb, S_IFDIR | 0755);
296 if (!root_inode)
297 return -ENOMEM;
298 root_inode->i_op = &simple_dir_inode_operations;
299 root_inode->i_fop = &simple_dir_operations;
300 sb->s_root = root_dentry = d_make_root(root_inode);
301 if (!root_dentry)
302 return -ENOMEM;
303 if (MACHINE_IS_VM)
304 rc = hypfs_vm_create_files(root_dentry);
305 else
306 rc = hypfs_diag_create_files(root_dentry);
307 if (rc)
308 return rc;
309 sbi->update_file = hypfs_create_update_file(root_dentry);
310 if (IS_ERR(sbi->update_file))
311 return PTR_ERR(sbi->update_file);
312 hypfs_update_update(sb);
313 pr_info("Hypervisor filesystem mounted\n");
314 return 0;
315}
316
317static struct dentry *hypfs_mount(struct file_system_type *fst, int flags,
318 const char *devname, void *data)
319{
320 return mount_single(fst, flags, data, hypfs_fill_super);
321}
322
323static void hypfs_kill_super(struct super_block *sb)
324{
325 struct hypfs_sb_info *sb_info = sb->s_fs_info;
326
327 if (sb->s_root)
328 hypfs_delete_tree(sb->s_root);
329 if (sb_info->update_file)
330 hypfs_remove(sb_info->update_file);
331 kfree(sb->s_fs_info);
332 sb->s_fs_info = NULL;
333 kill_litter_super(sb);
334}
335
336static struct dentry *hypfs_create_file(struct dentry *parent, const char *name,
337 char *data, umode_t mode)
338{
339 struct dentry *dentry;
340 struct inode *inode;
341
342 mutex_lock(&parent->d_inode->i_mutex);
343 dentry = lookup_one_len(name, parent, strlen(name));
344 if (IS_ERR(dentry)) {
345 dentry = ERR_PTR(-ENOMEM);
346 goto fail;
347 }
348 inode = hypfs_make_inode(parent->d_sb, mode);
349 if (!inode) {
350 dput(dentry);
351 dentry = ERR_PTR(-ENOMEM);
352 goto fail;
353 }
354 if (S_ISREG(mode)) {
355 inode->i_fop = &hypfs_file_ops;
356 if (data)
357 inode->i_size = strlen(data);
358 else
359 inode->i_size = 0;
360 } else if (S_ISDIR(mode)) {
361 inode->i_op = &simple_dir_inode_operations;
362 inode->i_fop = &simple_dir_operations;
363 inc_nlink(parent->d_inode);
364 } else
365 BUG();
366 inode->i_private = data;
367 d_instantiate(dentry, inode);
368 dget(dentry);
369fail:
370 mutex_unlock(&parent->d_inode->i_mutex);
371 return dentry;
372}
373
374struct dentry *hypfs_mkdir(struct dentry *parent, const char *name)
375{
376 struct dentry *dentry;
377
378 dentry = hypfs_create_file(parent, name, NULL, S_IFDIR | DIR_MODE);
379 if (IS_ERR(dentry))
380 return dentry;
381 hypfs_add_dentry(dentry);
382 return dentry;
383}
384
385static struct dentry *hypfs_create_update_file(struct dentry *dir)
386{
387 struct dentry *dentry;
388
389 dentry = hypfs_create_file(dir, "update", NULL,
390 S_IFREG | UPDATE_FILE_MODE);
391 /*
392 * We do not put the update file on the 'delete' list with
393 * hypfs_add_dentry(), since it should not be removed when the tree
394 * is updated.
395 */
396 return dentry;
397}
398
399struct dentry *hypfs_create_u64(struct dentry *dir,
400 const char *name, __u64 value)
401{
402 char *buffer;
403 char tmp[TMP_SIZE];
404 struct dentry *dentry;
405
406 snprintf(tmp, TMP_SIZE, "%llu\n", (unsigned long long int)value);
407 buffer = kstrdup(tmp, GFP_KERNEL);
408 if (!buffer)
409 return ERR_PTR(-ENOMEM);
410 dentry =
411 hypfs_create_file(dir, name, buffer, S_IFREG | REG_FILE_MODE);
412 if (IS_ERR(dentry)) {
413 kfree(buffer);
414 return ERR_PTR(-ENOMEM);
415 }
416 hypfs_add_dentry(dentry);
417 return dentry;
418}
419
420struct dentry *hypfs_create_str(struct dentry *dir,
421 const char *name, char *string)
422{
423 char *buffer;
424 struct dentry *dentry;
425
426 buffer = kmalloc(strlen(string) + 2, GFP_KERNEL);
427 if (!buffer)
428 return ERR_PTR(-ENOMEM);
429 sprintf(buffer, "%s\n", string);
430 dentry =
431 hypfs_create_file(dir, name, buffer, S_IFREG | REG_FILE_MODE);
432 if (IS_ERR(dentry)) {
433 kfree(buffer);
434 return ERR_PTR(-ENOMEM);
435 }
436 hypfs_add_dentry(dentry);
437 return dentry;
438}
439
440static const struct file_operations hypfs_file_ops = {
441 .open = hypfs_open,
442 .release = hypfs_release,
443 .read = do_sync_read,
444 .write = do_sync_write,
445 .aio_read = hypfs_aio_read,
446 .aio_write = hypfs_aio_write,
447 .llseek = no_llseek,
448};
449
450static struct file_system_type hypfs_type = {
451 .owner = THIS_MODULE,
452 .name = "s390_hypfs",
453 .mount = hypfs_mount,
454 .kill_sb = hypfs_kill_super
455};
456MODULE_ALIAS_FS("s390_hypfs");
457
458static const struct super_operations hypfs_s_ops = {
459 .statfs = simple_statfs,
460 .evict_inode = hypfs_evict_inode,
461 .show_options = hypfs_show_options,
462};
463
464static struct kobject *s390_kobj;
465
466static int __init hypfs_init(void)
467{
468 int rc;
469
470 rc = hypfs_dbfs_init();
471 if (rc)
472 return rc;
473 if (hypfs_diag_init()) {
474 rc = -ENODATA;
475 goto fail_dbfs_exit;
476 }
477 if (hypfs_vm_init()) {
478 rc = -ENODATA;
479 goto fail_hypfs_diag_exit;
480 }
481 if (hypfs_sprp_init()) {
482 rc = -ENODATA;
483 goto fail_hypfs_vm_exit;
484 }
485 s390_kobj = kobject_create_and_add("s390", hypervisor_kobj);
486 if (!s390_kobj) {
487 rc = -ENOMEM;
488 goto fail_hypfs_sprp_exit;
489 }
490 rc = register_filesystem(&hypfs_type);
491 if (rc)
492 goto fail_filesystem;
493 return 0;
494
495fail_filesystem:
496 kobject_put(s390_kobj);
497fail_hypfs_sprp_exit:
498 hypfs_sprp_exit();
499fail_hypfs_vm_exit:
500 hypfs_vm_exit();
501fail_hypfs_diag_exit:
502 hypfs_diag_exit();
503fail_dbfs_exit:
504 hypfs_dbfs_exit();
505 pr_err("Initialization of hypfs failed with rc=%i\n", rc);
506 return rc;
507}
508
509static void __exit hypfs_exit(void)
510{
511 unregister_filesystem(&hypfs_type);
512 kobject_put(s390_kobj);
513 hypfs_sprp_exit();
514 hypfs_vm_exit();
515 hypfs_diag_exit();
516 hypfs_dbfs_exit();
517}
518
519module_init(hypfs_init)
520module_exit(hypfs_exit)
521
522MODULE_LICENSE("GPL");
523MODULE_AUTHOR("Michael Holzheu <holzheu@de.ibm.com>");
524MODULE_DESCRIPTION("s390 Hypervisor Filesystem");