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v6.2
  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)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
v3.1
 
  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, int 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 (mode & S_IFDIR)
111			ret->i_nlink = 2;
112		else
113			ret->i_nlink = 1;
114	}
115	return ret;
116}
117
118static void hypfs_evict_inode(struct inode *inode)
119{
120	end_writeback(inode);
121	kfree(inode->i_private);
122}
123
124static int hypfs_open(struct inode *inode, struct file *filp)
125{
126	char *data = filp->f_path.dentry->d_inode->i_private;
127	struct hypfs_sb_info *fs_info;
128
129	if (filp->f_mode & FMODE_WRITE) {
130		if (!(inode->i_mode & S_IWUGO))
131			return -EACCES;
132	}
133	if (filp->f_mode & FMODE_READ) {
134		if (!(inode->i_mode & S_IRUGO))
135			return -EACCES;
136	}
137
138	fs_info = inode->i_sb->s_fs_info;
139	if(data) {
140		mutex_lock(&fs_info->lock);
141		filp->private_data = kstrdup(data, GFP_KERNEL);
142		if (!filp->private_data) {
143			mutex_unlock(&fs_info->lock);
144			return -ENOMEM;
145		}
146		mutex_unlock(&fs_info->lock);
147	}
148	return nonseekable_open(inode, filp);
149}
150
151static ssize_t hypfs_aio_read(struct kiocb *iocb, const struct iovec *iov,
152			      unsigned long nr_segs, loff_t offset)
153{
154	char *data;
155	ssize_t ret;
156	struct file *filp = iocb->ki_filp;
157	/* XXX: temporary */
158	char __user *buf = iov[0].iov_base;
159	size_t count = iov[0].iov_len;
160
161	if (nr_segs != 1)
162		return -EINVAL;
 
 
 
 
 
 
 
 
 
163
164	data = filp->private_data;
165	ret = simple_read_from_buffer(buf, count, &offset, data, strlen(data));
166	if (ret <= 0)
167		return ret;
168
169	iocb->ki_pos += ret;
170	file_accessed(filp);
171
172	return ret;
173}
174static ssize_t hypfs_aio_write(struct kiocb *iocb, const struct iovec *iov,
175			      unsigned long nr_segs, loff_t offset)
176{
177	int rc;
178	struct super_block *sb;
179	struct hypfs_sb_info *fs_info;
180	size_t count = iov_length(iov, nr_segs);
181
182	sb = iocb->ki_filp->f_path.dentry->d_inode->i_sb;
183	fs_info = sb->s_fs_info;
184	/*
185	 * Currently we only allow one update per second for two reasons:
186	 * 1. diag 204 is VERY expensive
187	 * 2. If several processes do updates in parallel and then read the
188	 *    hypfs data, the likelihood of collisions is reduced, if we restrict
189	 *    the minimum update interval. A collision occurs, if during the
190	 *    data gathering of one process another process triggers an update
191	 *    If the first process wants to ensure consistent data, it has
192	 *    to restart data collection in this case.
193	 */
194	mutex_lock(&fs_info->lock);
195	if (fs_info->last_update == get_seconds()) {
196		rc = -EBUSY;
197		goto out;
198	}
199	hypfs_delete_tree(sb->s_root);
200	if (MACHINE_IS_VM)
201		rc = hypfs_vm_create_files(sb, sb->s_root);
202	else
203		rc = hypfs_diag_create_files(sb, sb->s_root);
204	if (rc) {
205		pr_err("Updating the hypfs tree failed\n");
206		hypfs_delete_tree(sb->s_root);
207		goto out;
208	}
209	hypfs_update_update(sb);
210	rc = count;
 
211out:
212	mutex_unlock(&fs_info->lock);
213	return rc;
214}
215
216static int hypfs_release(struct inode *inode, struct file *filp)
217{
218	kfree(filp->private_data);
219	return 0;
220}
221
222enum { opt_uid, opt_gid, opt_err };
223
224static const match_table_t hypfs_tokens = {
225	{opt_uid, "uid=%u"},
226	{opt_gid, "gid=%u"},
227	{opt_err, NULL}
228};
229
230static int hypfs_parse_options(char *options, struct super_block *sb)
231{
232	char *str;
233	substring_t args[MAX_OPT_ARGS];
234
235	if (!options)
236		return 0;
237	while ((str = strsep(&options, ",")) != NULL) {
238		int token, option;
239		struct hypfs_sb_info *hypfs_info = sb->s_fs_info;
240
241		if (!*str)
242			continue;
243		token = match_token(str, hypfs_tokens, args);
244		switch (token) {
245		case opt_uid:
246			if (match_int(&args[0], &option))
247				return -EINVAL;
248			hypfs_info->uid = option;
249			break;
250		case opt_gid:
251			if (match_int(&args[0], &option))
252				return -EINVAL;
253			hypfs_info->gid = option;
254			break;
255		case opt_err:
256		default:
257			pr_err("%s is not a valid mount option\n", str);
258			return -EINVAL;
259		}
260	}
261	return 0;
262}
263
264static int hypfs_show_options(struct seq_file *s, struct vfsmount *mnt)
265{
266	struct hypfs_sb_info *hypfs_info = mnt->mnt_sb->s_fs_info;
267
268	seq_printf(s, ",uid=%u", hypfs_info->uid);
269	seq_printf(s, ",gid=%u", hypfs_info->gid);
270	return 0;
271}
272
273static int hypfs_fill_super(struct super_block *sb, void *data, int silent)
274{
 
275	struct inode *root_inode;
276	struct dentry *root_dentry;
277	int rc = 0;
278	struct hypfs_sb_info *sbi;
279
280	sbi = kzalloc(sizeof(struct hypfs_sb_info), GFP_KERNEL);
281	if (!sbi)
282		return -ENOMEM;
283	mutex_init(&sbi->lock);
284	sbi->uid = current_uid();
285	sbi->gid = current_gid();
286	sb->s_fs_info = sbi;
287	sb->s_blocksize = PAGE_CACHE_SIZE;
288	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
289	sb->s_magic = HYPFS_MAGIC;
290	sb->s_op = &hypfs_s_ops;
291	if (hypfs_parse_options(data, sb))
292		return -EINVAL;
293	root_inode = hypfs_make_inode(sb, S_IFDIR | 0755);
294	if (!root_inode)
295		return -ENOMEM;
296	root_inode->i_op = &simple_dir_inode_operations;
297	root_inode->i_fop = &simple_dir_operations;
298	sb->s_root = root_dentry = d_alloc_root(root_inode);
299	if (!root_dentry) {
300		iput(root_inode);
301		return -ENOMEM;
302	}
303	if (MACHINE_IS_VM)
304		rc = hypfs_vm_create_files(sb, root_dentry);
305	else
306		rc = hypfs_diag_create_files(sb, root_dentry);
307	if (rc)
308		return rc;
309	sbi->update_file = hypfs_create_update_file(sb, 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 super_block *sb,
337					struct dentry *parent, const char *name,
338					char *data, mode_t mode)
339{
340	struct dentry *dentry;
341	struct inode *inode;
342
343	mutex_lock(&parent->d_inode->i_mutex);
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(sb, mode);
350	if (!inode) {
351		dput(dentry);
352		dentry = ERR_PTR(-ENOMEM);
353		goto fail;
354	}
355	if (mode & S_IFREG) {
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 (mode & S_IFDIR) {
362		inode->i_op = &simple_dir_inode_operations;
363		inode->i_fop = &simple_dir_operations;
364		parent->d_inode->i_nlink++;
365	} else
366		BUG();
367	inode->i_private = data;
368	d_instantiate(dentry, inode);
369	dget(dentry);
370fail:
371	mutex_unlock(&parent->d_inode->i_mutex);
372	return dentry;
373}
374
375struct dentry *hypfs_mkdir(struct super_block *sb, struct dentry *parent,
376			   const char *name)
377{
378	struct dentry *dentry;
379
380	dentry = hypfs_create_file(sb, parent, name, NULL, S_IFDIR | DIR_MODE);
381	if (IS_ERR(dentry))
382		return dentry;
383	hypfs_add_dentry(dentry);
384	return dentry;
385}
386
387static struct dentry *hypfs_create_update_file(struct super_block *sb,
388					       struct dentry *dir)
389{
390	struct dentry *dentry;
391
392	dentry = hypfs_create_file(sb, dir, "update", NULL,
393				   S_IFREG | UPDATE_FILE_MODE);
394	/*
395	 * We do not put the update file on the 'delete' list with
396	 * hypfs_add_dentry(), since it should not be removed when the tree
397	 * is updated.
398	 */
399	return dentry;
400}
401
402struct dentry *hypfs_create_u64(struct super_block *sb, struct dentry *dir,
403				const char *name, __u64 value)
404{
405	char *buffer;
406	char tmp[TMP_SIZE];
407	struct dentry *dentry;
408
409	snprintf(tmp, TMP_SIZE, "%llu\n", (unsigned long long int)value);
410	buffer = kstrdup(tmp, GFP_KERNEL);
411	if (!buffer)
412		return ERR_PTR(-ENOMEM);
413	dentry =
414	    hypfs_create_file(sb, dir, name, buffer, S_IFREG | REG_FILE_MODE);
415	if (IS_ERR(dentry)) {
416		kfree(buffer);
417		return ERR_PTR(-ENOMEM);
418	}
419	hypfs_add_dentry(dentry);
420	return dentry;
421}
422
423struct dentry *hypfs_create_str(struct super_block *sb, struct dentry *dir,
424				const char *name, char *string)
425{
426	char *buffer;
427	struct dentry *dentry;
428
429	buffer = kmalloc(strlen(string) + 2, GFP_KERNEL);
430	if (!buffer)
431		return ERR_PTR(-ENOMEM);
432	sprintf(buffer, "%s\n", string);
433	dentry =
434	    hypfs_create_file(sb, dir, name, buffer, S_IFREG | REG_FILE_MODE);
435	if (IS_ERR(dentry)) {
436		kfree(buffer);
437		return ERR_PTR(-ENOMEM);
438	}
439	hypfs_add_dentry(dentry);
440	return dentry;
441}
442
443static const struct file_operations hypfs_file_ops = {
444	.open		= hypfs_open,
445	.release	= hypfs_release,
446	.read		= do_sync_read,
447	.write		= do_sync_write,
448	.aio_read	= hypfs_aio_read,
449	.aio_write	= hypfs_aio_write,
450	.llseek		= no_llseek,
451};
452
453static struct file_system_type hypfs_type = {
454	.owner		= THIS_MODULE,
455	.name		= "s390_hypfs",
456	.mount		= hypfs_mount,
 
457	.kill_sb	= hypfs_kill_super
458};
459
460static const struct super_operations hypfs_s_ops = {
461	.statfs		= simple_statfs,
462	.evict_inode	= hypfs_evict_inode,
463	.show_options	= hypfs_show_options,
464};
465
466static struct kobject *s390_kobj;
467
468static int __init hypfs_init(void)
469{
470	int rc;
471
472	rc = hypfs_dbfs_init();
473	if (rc)
474		return rc;
475	if (hypfs_diag_init()) {
476		rc = -ENODATA;
477		goto fail_dbfs_exit;
478	}
479	if (hypfs_vm_init()) {
480		rc = -ENODATA;
481		goto fail_hypfs_diag_exit;
482	}
483	s390_kobj = kobject_create_and_add("s390", hypervisor_kobj);
484	if (!s390_kobj) {
485		rc = -ENOMEM;
486		goto fail_hypfs_vm_exit;
487	}
 
 
 
488	rc = register_filesystem(&hypfs_type);
489	if (rc)
490		goto fail_filesystem;
491	return 0;
492
493fail_filesystem:
494	kobject_put(s390_kobj);
495fail_hypfs_vm_exit:
 
 
 
496	hypfs_vm_exit();
497fail_hypfs_diag_exit:
498	hypfs_diag_exit();
 
499fail_dbfs_exit:
500	hypfs_dbfs_exit();
501	pr_err("Initialization of hypfs failed with rc=%i\n", rc);
502	return rc;
503}
504
505static void __exit hypfs_exit(void)
506{
507	hypfs_diag_exit();
508	hypfs_vm_exit();
509	hypfs_dbfs_exit();
510	unregister_filesystem(&hypfs_type);
511	kobject_put(s390_kobj);
512}
513
514module_init(hypfs_init)
515module_exit(hypfs_exit)
516
517MODULE_LICENSE("GPL");
518MODULE_AUTHOR("Michael Holzheu <holzheu@de.ibm.com>");
519MODULE_DESCRIPTION("s390 Hypervisor Filesystem");