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1// SPDX-License-Identifier: GPL-1.0+
2/*
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/fs_context.h>
16#include <linux/fs_parser.h>
17#include <linux/namei.h>
18#include <linux/vfs.h>
19#include <linux/slab.h>
20#include <linux/pagemap.h>
21#include <linux/time.h>
22#include <linux/sysfs.h>
23#include <linux/init.h>
24#include <linux/kobject.h>
25#include <linux/seq_file.h>
26#include <linux/uio.h>
27#include <asm/ebcdic.h>
28#include "hypfs.h"
29
30#define HYPFS_MAGIC 0x687970 /* ASCII 'hyp' */
31#define TMP_SIZE 64 /* size of temporary buffers */
32
33static struct dentry *hypfs_create_update_file(struct dentry *dir);
34
35struct hypfs_sb_info {
36 kuid_t uid; /* uid used for files and dirs */
37 kgid_t gid; /* gid used for files and dirs */
38 struct dentry *update_file; /* file to trigger update */
39 time64_t last_update; /* last update, CLOCK_MONOTONIC time */
40 struct mutex lock; /* lock to protect update process */
41};
42
43static const struct file_operations hypfs_file_ops;
44static struct file_system_type hypfs_type;
45static const struct super_operations hypfs_s_ops;
46
47/* start of list of all dentries, which have to be deleted on update */
48static struct dentry *hypfs_last_dentry;
49
50static void hypfs_update_update(struct super_block *sb)
51{
52 struct hypfs_sb_info *sb_info = sb->s_fs_info;
53 struct inode *inode = d_inode(sb_info->update_file);
54
55 sb_info->last_update = ktime_get_seconds();
56 inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
57}
58
59/* directory tree removal functions */
60
61static void hypfs_add_dentry(struct dentry *dentry)
62{
63 dentry->d_fsdata = hypfs_last_dentry;
64 hypfs_last_dentry = dentry;
65}
66
67static void hypfs_remove(struct dentry *dentry)
68{
69 struct dentry *parent;
70
71 parent = dentry->d_parent;
72 inode_lock(d_inode(parent));
73 if (simple_positive(dentry)) {
74 if (d_is_dir(dentry))
75 simple_rmdir(d_inode(parent), dentry);
76 else
77 simple_unlink(d_inode(parent), dentry);
78 }
79 d_drop(dentry);
80 dput(dentry);
81 inode_unlock(d_inode(parent));
82}
83
84static void hypfs_delete_tree(struct dentry *root)
85{
86 while (hypfs_last_dentry) {
87 struct dentry *next_dentry;
88 next_dentry = hypfs_last_dentry->d_fsdata;
89 hypfs_remove(hypfs_last_dentry);
90 hypfs_last_dentry = next_dentry;
91 }
92}
93
94static struct inode *hypfs_make_inode(struct super_block *sb, umode_t mode)
95{
96 struct inode *ret = new_inode(sb);
97
98 if (ret) {
99 struct hypfs_sb_info *hypfs_info = sb->s_fs_info;
100 ret->i_ino = get_next_ino();
101 ret->i_mode = mode;
102 ret->i_uid = hypfs_info->uid;
103 ret->i_gid = hypfs_info->gid;
104 ret->i_atime = ret->i_mtime = ret->i_ctime = current_time(ret);
105 if (S_ISDIR(mode))
106 set_nlink(ret, 2);
107 }
108 return ret;
109}
110
111static void hypfs_evict_inode(struct inode *inode)
112{
113 clear_inode(inode);
114 kfree(inode->i_private);
115}
116
117static int hypfs_open(struct inode *inode, struct file *filp)
118{
119 char *data = file_inode(filp)->i_private;
120 struct hypfs_sb_info *fs_info;
121
122 if (filp->f_mode & FMODE_WRITE) {
123 if (!(inode->i_mode & S_IWUGO))
124 return -EACCES;
125 }
126 if (filp->f_mode & FMODE_READ) {
127 if (!(inode->i_mode & S_IRUGO))
128 return -EACCES;
129 }
130
131 fs_info = inode->i_sb->s_fs_info;
132 if(data) {
133 mutex_lock(&fs_info->lock);
134 filp->private_data = kstrdup(data, GFP_KERNEL);
135 if (!filp->private_data) {
136 mutex_unlock(&fs_info->lock);
137 return -ENOMEM;
138 }
139 mutex_unlock(&fs_info->lock);
140 }
141 return nonseekable_open(inode, filp);
142}
143
144static ssize_t hypfs_read_iter(struct kiocb *iocb, struct iov_iter *to)
145{
146 struct file *file = iocb->ki_filp;
147 char *data = file->private_data;
148 size_t available = strlen(data);
149 loff_t pos = iocb->ki_pos;
150 size_t count;
151
152 if (pos < 0)
153 return -EINVAL;
154 if (pos >= available || !iov_iter_count(to))
155 return 0;
156 count = copy_to_iter(data + pos, available - pos, to);
157 if (!count)
158 return -EFAULT;
159 iocb->ki_pos = pos + count;
160 file_accessed(file);
161 return count;
162}
163
164static ssize_t hypfs_write_iter(struct kiocb *iocb, struct iov_iter *from)
165{
166 int rc;
167 struct super_block *sb = file_inode(iocb->ki_filp)->i_sb;
168 struct hypfs_sb_info *fs_info = sb->s_fs_info;
169 size_t count = iov_iter_count(from);
170
171 /*
172 * Currently we only allow one update per second for two reasons:
173 * 1. diag 204 is VERY expensive
174 * 2. If several processes do updates in parallel and then read the
175 * hypfs data, the likelihood of collisions is reduced, if we restrict
176 * the minimum update interval. A collision occurs, if during the
177 * data gathering of one process another process triggers an update
178 * If the first process wants to ensure consistent data, it has
179 * to restart data collection in this case.
180 */
181 mutex_lock(&fs_info->lock);
182 if (fs_info->last_update == ktime_get_seconds()) {
183 rc = -EBUSY;
184 goto out;
185 }
186 hypfs_delete_tree(sb->s_root);
187 if (MACHINE_IS_VM)
188 rc = hypfs_vm_create_files(sb->s_root);
189 else
190 rc = hypfs_diag_create_files(sb->s_root);
191 if (rc) {
192 pr_err("Updating the hypfs tree failed\n");
193 hypfs_delete_tree(sb->s_root);
194 goto out;
195 }
196 hypfs_update_update(sb);
197 rc = count;
198 iov_iter_advance(from, count);
199out:
200 mutex_unlock(&fs_info->lock);
201 return rc;
202}
203
204static int hypfs_release(struct inode *inode, struct file *filp)
205{
206 kfree(filp->private_data);
207 return 0;
208}
209
210enum { Opt_uid, Opt_gid, };
211
212static const struct fs_parameter_spec hypfs_fs_parameters[] = {
213 fsparam_u32("gid", Opt_gid),
214 fsparam_u32("uid", Opt_uid),
215 {}
216};
217
218static int hypfs_parse_param(struct fs_context *fc, struct fs_parameter *param)
219{
220 struct hypfs_sb_info *hypfs_info = fc->s_fs_info;
221 struct fs_parse_result result;
222 kuid_t uid;
223 kgid_t gid;
224 int opt;
225
226 opt = fs_parse(fc, hypfs_fs_parameters, param, &result);
227 if (opt < 0)
228 return opt;
229
230 switch (opt) {
231 case Opt_uid:
232 uid = make_kuid(current_user_ns(), result.uint_32);
233 if (!uid_valid(uid))
234 return invalf(fc, "Unknown uid");
235 hypfs_info->uid = uid;
236 break;
237 case Opt_gid:
238 gid = make_kgid(current_user_ns(), result.uint_32);
239 if (!gid_valid(gid))
240 return invalf(fc, "Unknown gid");
241 hypfs_info->gid = gid;
242 break;
243 }
244 return 0;
245}
246
247static int hypfs_show_options(struct seq_file *s, struct dentry *root)
248{
249 struct hypfs_sb_info *hypfs_info = root->d_sb->s_fs_info;
250
251 seq_printf(s, ",uid=%u", from_kuid_munged(&init_user_ns, hypfs_info->uid));
252 seq_printf(s, ",gid=%u", from_kgid_munged(&init_user_ns, hypfs_info->gid));
253 return 0;
254}
255
256static int hypfs_fill_super(struct super_block *sb, struct fs_context *fc)
257{
258 struct hypfs_sb_info *sbi = sb->s_fs_info;
259 struct inode *root_inode;
260 struct dentry *root_dentry, *update_file;
261 int rc;
262
263 sb->s_blocksize = PAGE_SIZE;
264 sb->s_blocksize_bits = PAGE_SHIFT;
265 sb->s_magic = HYPFS_MAGIC;
266 sb->s_op = &hypfs_s_ops;
267
268 root_inode = hypfs_make_inode(sb, S_IFDIR | 0755);
269 if (!root_inode)
270 return -ENOMEM;
271 root_inode->i_op = &simple_dir_inode_operations;
272 root_inode->i_fop = &simple_dir_operations;
273 sb->s_root = root_dentry = d_make_root(root_inode);
274 if (!root_dentry)
275 return -ENOMEM;
276 if (MACHINE_IS_VM)
277 rc = hypfs_vm_create_files(root_dentry);
278 else
279 rc = hypfs_diag_create_files(root_dentry);
280 if (rc)
281 return rc;
282 update_file = hypfs_create_update_file(root_dentry);
283 if (IS_ERR(update_file))
284 return PTR_ERR(update_file);
285 sbi->update_file = update_file;
286 hypfs_update_update(sb);
287 pr_info("Hypervisor filesystem mounted\n");
288 return 0;
289}
290
291static int hypfs_get_tree(struct fs_context *fc)
292{
293 return get_tree_single(fc, hypfs_fill_super);
294}
295
296static void hypfs_free_fc(struct fs_context *fc)
297{
298 kfree(fc->s_fs_info);
299}
300
301static const struct fs_context_operations hypfs_context_ops = {
302 .free = hypfs_free_fc,
303 .parse_param = hypfs_parse_param,
304 .get_tree = hypfs_get_tree,
305};
306
307static int hypfs_init_fs_context(struct fs_context *fc)
308{
309 struct hypfs_sb_info *sbi;
310
311 sbi = kzalloc(sizeof(struct hypfs_sb_info), GFP_KERNEL);
312 if (!sbi)
313 return -ENOMEM;
314
315 mutex_init(&sbi->lock);
316 sbi->uid = current_uid();
317 sbi->gid = current_gid();
318
319 fc->s_fs_info = sbi;
320 fc->ops = &hypfs_context_ops;
321 return 0;
322}
323
324static void hypfs_kill_super(struct super_block *sb)
325{
326 struct hypfs_sb_info *sb_info = sb->s_fs_info;
327
328 if (sb->s_root)
329 hypfs_delete_tree(sb->s_root);
330 if (sb_info && sb_info->update_file)
331 hypfs_remove(sb_info->update_file);
332 kfree(sb->s_fs_info);
333 sb->s_fs_info = NULL;
334 kill_litter_super(sb);
335}
336
337static struct dentry *hypfs_create_file(struct dentry *parent, const char *name,
338 char *data, umode_t mode)
339{
340 struct dentry *dentry;
341 struct inode *inode;
342
343 inode_lock(d_inode(parent));
344 dentry = lookup_one_len(name, parent, strlen(name));
345 if (IS_ERR(dentry)) {
346 dentry = ERR_PTR(-ENOMEM);
347 goto fail;
348 }
349 inode = hypfs_make_inode(parent->d_sb, mode);
350 if (!inode) {
351 dput(dentry);
352 dentry = ERR_PTR(-ENOMEM);
353 goto fail;
354 }
355 if (S_ISREG(mode)) {
356 inode->i_fop = &hypfs_file_ops;
357 if (data)
358 inode->i_size = strlen(data);
359 else
360 inode->i_size = 0;
361 } else if (S_ISDIR(mode)) {
362 inode->i_op = &simple_dir_inode_operations;
363 inode->i_fop = &simple_dir_operations;
364 inc_nlink(d_inode(parent));
365 } else
366 BUG();
367 inode->i_private = data;
368 d_instantiate(dentry, inode);
369 dget(dentry);
370fail:
371 inode_unlock(d_inode(parent));
372 return dentry;
373}
374
375struct dentry *hypfs_mkdir(struct dentry *parent, const char *name)
376{
377 struct dentry *dentry;
378
379 dentry = hypfs_create_file(parent, name, NULL, S_IFDIR | DIR_MODE);
380 if (IS_ERR(dentry))
381 return dentry;
382 hypfs_add_dentry(dentry);
383 return dentry;
384}
385
386static struct dentry *hypfs_create_update_file(struct dentry *dir)
387{
388 struct dentry *dentry;
389
390 dentry = hypfs_create_file(dir, "update", NULL,
391 S_IFREG | UPDATE_FILE_MODE);
392 /*
393 * We do not put the update file on the 'delete' list with
394 * hypfs_add_dentry(), since it should not be removed when the tree
395 * is updated.
396 */
397 return dentry;
398}
399
400struct dentry *hypfs_create_u64(struct dentry *dir,
401 const char *name, __u64 value)
402{
403 char *buffer;
404 char tmp[TMP_SIZE];
405 struct dentry *dentry;
406
407 snprintf(tmp, TMP_SIZE, "%llu\n", (unsigned long long int)value);
408 buffer = kstrdup(tmp, GFP_KERNEL);
409 if (!buffer)
410 return ERR_PTR(-ENOMEM);
411 dentry =
412 hypfs_create_file(dir, name, buffer, S_IFREG | REG_FILE_MODE);
413 if (IS_ERR(dentry)) {
414 kfree(buffer);
415 return ERR_PTR(-ENOMEM);
416 }
417 hypfs_add_dentry(dentry);
418 return dentry;
419}
420
421struct dentry *hypfs_create_str(struct dentry *dir,
422 const char *name, char *string)
423{
424 char *buffer;
425 struct dentry *dentry;
426
427 buffer = kmalloc(strlen(string) + 2, GFP_KERNEL);
428 if (!buffer)
429 return ERR_PTR(-ENOMEM);
430 sprintf(buffer, "%s\n", string);
431 dentry =
432 hypfs_create_file(dir, name, buffer, S_IFREG | REG_FILE_MODE);
433 if (IS_ERR(dentry)) {
434 kfree(buffer);
435 return ERR_PTR(-ENOMEM);
436 }
437 hypfs_add_dentry(dentry);
438 return dentry;
439}
440
441static const struct file_operations hypfs_file_ops = {
442 .open = hypfs_open,
443 .release = hypfs_release,
444 .read_iter = hypfs_read_iter,
445 .write_iter = hypfs_write_iter,
446 .llseek = no_llseek,
447};
448
449static struct file_system_type hypfs_type = {
450 .owner = THIS_MODULE,
451 .name = "s390_hypfs",
452 .init_fs_context = hypfs_init_fs_context,
453 .parameters = hypfs_fs_parameters,
454 .kill_sb = hypfs_kill_super
455};
456
457static const struct super_operations hypfs_s_ops = {
458 .statfs = simple_statfs,
459 .evict_inode = hypfs_evict_inode,
460 .show_options = hypfs_show_options,
461};
462
463static int __init hypfs_init(void)
464{
465 int rc;
466
467 hypfs_dbfs_init();
468
469 if (hypfs_diag_init()) {
470 rc = -ENODATA;
471 goto fail_dbfs_exit;
472 }
473 if (hypfs_vm_init()) {
474 rc = -ENODATA;
475 goto fail_hypfs_diag_exit;
476 }
477 hypfs_sprp_init();
478 if (hypfs_diag0c_init()) {
479 rc = -ENODATA;
480 goto fail_hypfs_sprp_exit;
481 }
482 rc = sysfs_create_mount_point(hypervisor_kobj, "s390");
483 if (rc)
484 goto fail_hypfs_diag0c_exit;
485 rc = register_filesystem(&hypfs_type);
486 if (rc)
487 goto fail_filesystem;
488 return 0;
489
490fail_filesystem:
491 sysfs_remove_mount_point(hypervisor_kobj, "s390");
492fail_hypfs_diag0c_exit:
493 hypfs_diag0c_exit();
494fail_hypfs_sprp_exit:
495 hypfs_sprp_exit();
496 hypfs_vm_exit();
497fail_hypfs_diag_exit:
498 hypfs_diag_exit();
499 pr_err("Initialization of hypfs failed with rc=%i\n", rc);
500fail_dbfs_exit:
501 hypfs_dbfs_exit();
502 return rc;
503}
504device_initcall(hypfs_init)
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");