[deliverable/linux.git] / arch / s390 / hypfs / inode.c

/*
 *  arch/s390/hypfs/inode.c
 *    Hypervisor filesystem for Linux on s390.
 *
 *    Copyright (C) IBM Corp. 2006
 *    Author(s): Michael Holzheu <holzheu@de.ibm.com>
 */

#include <linux/types.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/namei.h>
#include <linux/vfs.h>
#include <linux/pagemap.h>
#include <linux/gfp.h>
#include <linux/time.h>
#include <linux/parser.h>
#include <linux/sysfs.h>
#include <linux/module.h>
#include <linux/seq_file.h>
#include <linux/mount.h>
#include <asm/ebcdic.h>
#include "hypfs.h"

#define HYPFS_MAGIC 0x687970	/* ASCII 'hyp' */
#define TMP_SIZE 64		/* size of temporary buffers */

static struct dentry *hypfs_create_update_file(struct super_block *sb,
					       struct dentry *dir);

struct hypfs_sb_info {
	uid_t uid;			/* uid used for files and dirs */
	gid_t gid;			/* gid used for files and dirs */
	struct dentry *update_file;	/* file to trigger update */
	time_t last_update;		/* last update time in secs since 1970 */
	struct mutex lock;		/* lock to protect update process */
};

static const struct file_operations hypfs_file_ops;
static struct file_system_type hypfs_type;
static struct super_operations hypfs_s_ops;

/* start of list of all dentries, which have to be deleted on update */
static struct dentry *hypfs_last_dentry;

static void hypfs_update_update(struct super_block *sb)
{
	struct hypfs_sb_info *sb_info = sb->s_fs_info;
	struct inode *inode = sb_info->update_file->d_inode;

	sb_info->last_update = get_seconds();
	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
}

/* directory tree removal functions */

static void hypfs_add_dentry(struct dentry *dentry)
{
	dentry->d_fsdata = hypfs_last_dentry;
	hypfs_last_dentry = dentry;
}

static void hypfs_remove(struct dentry *dentry)
{
	struct dentry *parent;

	parent = dentry->d_parent;
	if (S_ISDIR(dentry->d_inode->i_mode))
		simple_rmdir(parent->d_inode, dentry);
	else
		simple_unlink(parent->d_inode, dentry);
	d_delete(dentry);
	dput(dentry);
}

static void hypfs_delete_tree(struct dentry *root)
{
	while (hypfs_last_dentry) {
		struct dentry *next_dentry;
		next_dentry = hypfs_last_dentry->d_fsdata;
		hypfs_remove(hypfs_last_dentry);
		hypfs_last_dentry = next_dentry;
	}
}

static struct inode *hypfs_make_inode(struct super_block *sb, int mode)
{
	struct inode *ret = new_inode(sb);

	if (ret) {
		struct hypfs_sb_info *hypfs_info = sb->s_fs_info;
		ret->i_mode = mode;
		ret->i_uid = hypfs_info->uid;
		ret->i_gid = hypfs_info->gid;
		ret->i_blocks = 0;
		ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
		if (mode & S_IFDIR)
			ret->i_nlink = 2;
		else
			ret->i_nlink = 1;
	}
	return ret;
}

static void hypfs_drop_inode(struct inode *inode)
{
	kfree(inode->i_private);
	generic_delete_inode(inode);
}

static int hypfs_open(struct inode *inode, struct file *filp)
{
	char *data = filp->f_path.dentry->d_inode->i_private;
	struct hypfs_sb_info *fs_info;

	if (filp->f_mode & FMODE_WRITE) {
		if (!(inode->i_mode & S_IWUGO))
			return -EACCES;
	}
	if (filp->f_mode & FMODE_READ) {
		if (!(inode->i_mode & S_IRUGO))
			return -EACCES;
	}

	fs_info = inode->i_sb->s_fs_info;
	if(data) {
		mutex_lock(&fs_info->lock);
		filp->private_data = kstrdup(data, GFP_KERNEL);
		if (!filp->private_data) {
			mutex_unlock(&fs_info->lock);
			return -ENOMEM;
		}
		mutex_unlock(&fs_info->lock);
	}
	return 0;
}

static ssize_t hypfs_aio_read(struct kiocb *iocb, const struct iovec *iov,
			      unsigned long nr_segs, loff_t offset)
{
	char *data;
	size_t len;
	struct file *filp = iocb->ki_filp;
	/* XXX: temporary */
	char __user *buf = iov[0].iov_base;
	size_t count = iov[0].iov_len;

	if (nr_segs != 1) {
		count = -EINVAL;
		goto out;
	}

	data = filp->private_data;
	len = strlen(data);
	if (offset > len) {
		count = 0;
		goto out;
	}
	if (count > len - offset)
		count = len - offset;
	if (copy_to_user(buf, data + offset, count)) {
		count = -EFAULT;
		goto out;
	}
	iocb->ki_pos += count;
	file_accessed(filp);
out:
	return count;
}
static ssize_t hypfs_aio_write(struct kiocb *iocb, const struct iovec *iov,
			      unsigned long nr_segs, loff_t offset)
{
	int rc;
	struct super_block *sb;
	struct hypfs_sb_info *fs_info;
	size_t count = iov_length(iov, nr_segs);

	sb = iocb->ki_filp->f_path.dentry->d_inode->i_sb;
	fs_info = sb->s_fs_info;
	/*
	 * Currently we only allow one update per second for two reasons:
	 * 1. diag 204 is VERY expensive
	 * 2. If several processes do updates in parallel and then read the
	 *    hypfs data, the likelihood of collisions is reduced, if we restrict
	 *    the minimum update interval. A collision occurs, if during the
	 *    data gathering of one process another process triggers an update
	 *    If the first process wants to ensure consistent data, it has
	 *    to restart data collection in this case.
	 */
	mutex_lock(&fs_info->lock);
	if (fs_info->last_update == get_seconds()) {
		rc = -EBUSY;
		goto out;
	}
	hypfs_delete_tree(sb->s_root);
	if (MACHINE_IS_VM)
		rc = hypfs_vm_create_files(sb, sb->s_root);
	else
		rc = hypfs_diag_create_files(sb, sb->s_root);
	if (rc) {
		printk(KERN_ERR "hypfs: Update failed\n");
		hypfs_delete_tree(sb->s_root);
		goto out;
	}
	hypfs_update_update(sb);
	rc = count;
out:
	mutex_unlock(&fs_info->lock);
	return rc;
}

static int hypfs_release(struct inode *inode, struct file *filp)
{
	kfree(filp->private_data);
	return 0;
}

enum { opt_uid, opt_gid, opt_err };

static match_table_t hypfs_tokens = {
	{opt_uid, "uid=%u"},
	{opt_gid, "gid=%u"},
	{opt_err, NULL}
};

static int hypfs_parse_options(char *options, struct super_block *sb)
{
	char *str;
	substring_t args[MAX_OPT_ARGS];

	if (!options)
		return 0;
	while ((str = strsep(&options, ",")) != NULL) {
		int token, option;
		struct hypfs_sb_info *hypfs_info = sb->s_fs_info;

		if (!*str)
			continue;
		token = match_token(str, hypfs_tokens, args);
		switch (token) {
		case opt_uid:
			if (match_int(&args[0], &option))
				return -EINVAL;
			hypfs_info->uid = option;
			break;
		case opt_gid:
			if (match_int(&args[0], &option))
				return -EINVAL;
			hypfs_info->gid = option;
			break;
		case opt_err:
		default:
			printk(KERN_ERR "hypfs: Unrecognized mount option "
			       "\"%s\" or missing value\n", str);
			return -EINVAL;
		}
	}
	return 0;
}

static int hypfs_show_options(struct seq_file *s, struct vfsmount *mnt)
{
	struct hypfs_sb_info *hypfs_info = mnt->mnt_sb->s_fs_info;

	seq_printf(s, ",uid=%u", hypfs_info->uid);
	seq_printf(s, ",gid=%u", hypfs_info->gid);
	return 0;
}

static int hypfs_fill_super(struct super_block *sb, void *data, int silent)
{
	struct inode *root_inode;
	struct dentry *root_dentry;
	int rc = 0;
	struct hypfs_sb_info *sbi;

	sbi = kzalloc(sizeof(struct hypfs_sb_info), GFP_KERNEL);
	if (!sbi)
		return -ENOMEM;
	mutex_init(&sbi->lock);
	sbi->uid = current->uid;
	sbi->gid = current->gid;
	sb->s_fs_info = sbi;
	sb->s_blocksize = PAGE_CACHE_SIZE;
	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	sb->s_magic = HYPFS_MAGIC;
	sb->s_op = &hypfs_s_ops;
	if (hypfs_parse_options(data, sb)) {
		rc = -EINVAL;
		goto err_alloc;
	}
	root_inode = hypfs_make_inode(sb, S_IFDIR | 0755);
	if (!root_inode) {
		rc = -ENOMEM;
		goto err_alloc;
	}
	root_inode->i_op = &simple_dir_inode_operations;
	root_inode->i_fop = &simple_dir_operations;
	root_dentry = d_alloc_root(root_inode);
	if (!root_dentry) {
		iput(root_inode);
		rc = -ENOMEM;
		goto err_alloc;
	}
	if (MACHINE_IS_VM)
		rc = hypfs_vm_create_files(sb, root_dentry);
	else
		rc = hypfs_diag_create_files(sb, root_dentry);
	if (rc)
		goto err_tree;
	sbi->update_file = hypfs_create_update_file(sb, root_dentry);
	if (IS_ERR(sbi->update_file)) {
		rc = PTR_ERR(sbi->update_file);
		goto err_tree;
	}
	hypfs_update_update(sb);
	sb->s_root = root_dentry;
	return 0;

err_tree:
	hypfs_delete_tree(root_dentry);
	d_genocide(root_dentry);
	dput(root_dentry);
err_alloc:
	kfree(sbi);
	return rc;
}

static int hypfs_get_super(struct file_system_type *fst, int flags,
			const char *devname, void *data, struct vfsmount *mnt)
{
	return get_sb_single(fst, flags, data, hypfs_fill_super, mnt);
}

static void hypfs_kill_super(struct super_block *sb)
{
	struct hypfs_sb_info *sb_info = sb->s_fs_info;

	if (sb->s_root) {
		hypfs_delete_tree(sb->s_root);
		hypfs_remove(sb_info->update_file);
		kfree(sb->s_fs_info);
		sb->s_fs_info = NULL;
	}
	kill_litter_super(sb);
}

static struct dentry *hypfs_create_file(struct super_block *sb,
					struct dentry *parent, const char *name,
					char *data, mode_t mode)
{
	struct dentry *dentry;
	struct inode *inode;
	struct qstr qname;

	qname.name = name;
	qname.len = strlen(name);
	qname.hash = full_name_hash(name, qname.len);
	dentry = lookup_one_len(name, parent, strlen(name));
	if (IS_ERR(dentry))
		return ERR_PTR(-ENOMEM);
	inode = hypfs_make_inode(sb, mode);
	if (!inode) {
		dput(dentry);
		return ERR_PTR(-ENOMEM);
	}
	if (mode & S_IFREG) {
		inode->i_fop = &hypfs_file_ops;
		if (data)
			inode->i_size = strlen(data);
		else
			inode->i_size = 0;
	} else if (mode & S_IFDIR) {
		inode->i_op = &simple_dir_inode_operations;
		inode->i_fop = &simple_dir_operations;
		parent->d_inode->i_nlink++;
	} else
		BUG();
	inode->i_private = data;
	d_instantiate(dentry, inode);
	dget(dentry);
	return dentry;
}

struct dentry *hypfs_mkdir(struct super_block *sb, struct dentry *parent,
			   const char *name)
{
	struct dentry *dentry;

	dentry = hypfs_create_file(sb, parent, name, NULL, S_IFDIR | DIR_MODE);
	if (IS_ERR(dentry))
		return dentry;
	hypfs_add_dentry(dentry);
	parent->d_inode->i_nlink++;
	return dentry;
}

static struct dentry *hypfs_create_update_file(struct super_block *sb,
					       struct dentry *dir)
{
	struct dentry *dentry;

	dentry = hypfs_create_file(sb, dir, "update", NULL,
				   S_IFREG | UPDATE_FILE_MODE);
	/*
	 * We do not put the update file on the 'delete' list with
	 * hypfs_add_dentry(), since it should not be removed when the tree
	 * is updated.
	 */
	return dentry;
}

struct dentry *hypfs_create_u64(struct super_block *sb, struct dentry *dir,
				const char *name, __u64 value)
{
	char *buffer;
	char tmp[TMP_SIZE];
	struct dentry *dentry;

	snprintf(tmp, TMP_SIZE, "%lld\n", (unsigned long long int)value);
	buffer = kstrdup(tmp, GFP_KERNEL);
	if (!buffer)
		return ERR_PTR(-ENOMEM);
	dentry =
	    hypfs_create_file(sb, dir, name, buffer, S_IFREG | REG_FILE_MODE);
	if (IS_ERR(dentry)) {
		kfree(buffer);
		return ERR_PTR(-ENOMEM);
	}
	hypfs_add_dentry(dentry);
	return dentry;
}

struct dentry *hypfs_create_str(struct super_block *sb, struct dentry *dir,
				const char *name, char *string)
{
	char *buffer;
	struct dentry *dentry;

	buffer = kmalloc(strlen(string) + 2, GFP_KERNEL);
	if (!buffer)
		return ERR_PTR(-ENOMEM);
	sprintf(buffer, "%s\n", string);
	dentry =
	    hypfs_create_file(sb, dir, name, buffer, S_IFREG | REG_FILE_MODE);
	if (IS_ERR(dentry)) {
		kfree(buffer);
		return ERR_PTR(-ENOMEM);
	}
	hypfs_add_dentry(dentry);
	return dentry;
}

static const struct file_operations hypfs_file_ops = {
	.open		= hypfs_open,
	.release	= hypfs_release,
	.read		= do_sync_read,
	.write		= do_sync_write,
	.aio_read	= hypfs_aio_read,
	.aio_write	= hypfs_aio_write,
};

static struct file_system_type hypfs_type = {
	.owner		= THIS_MODULE,
	.name		= "s390_hypfs",
	.get_sb		= hypfs_get_super,
	.kill_sb	= hypfs_kill_super
};

static struct super_operations hypfs_s_ops = {
	.statfs		= simple_statfs,
	.drop_inode	= hypfs_drop_inode,
	.show_options	= hypfs_show_options,
};

static decl_subsys(s390, NULL, NULL);

static int __init hypfs_init(void)
{
	int rc;

	if (MACHINE_IS_VM) {
		if (hypfs_vm_init())
			/* no diag 2fc, just exit */
			return -ENODATA;
	} else {
		if (hypfs_diag_init()) {
			rc = -ENODATA;
			goto fail_diag;
		}
	}
	kobj_set_kset_s(&s390_subsys, hypervisor_subsys);
	rc = subsystem_register(&s390_subsys);
	if (rc)
		goto fail_sysfs;
	rc = register_filesystem(&hypfs_type);
	if (rc)
		goto fail_filesystem;
	return 0;

fail_filesystem:
	subsystem_unregister(&s390_subsys);
fail_sysfs:
	if (!MACHINE_IS_VM)
		hypfs_diag_exit();
fail_diag:
	printk(KERN_ERR "hypfs: Initialization failed with rc = %i.\n", rc);
	return rc;
}

static void __exit hypfs_exit(void)
{
	if (!MACHINE_IS_VM)
		hypfs_diag_exit();
	unregister_filesystem(&hypfs_type);
	subsystem_unregister(&s390_subsys);
}

module_init(hypfs_init)
module_exit(hypfs_exit)

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Michael Holzheu <holzheu@de.ibm.com>");
MODULE_DESCRIPTION("s390 Hypervisor Filesystem");
Commit	Line	Data
24bbb1fa	1	/*
f19bfb2c	2	* arch/s390/hypfs/inode.c
24bbb1fa MH	3	* Hypervisor filesystem for Linux on s390.
	4	*
	5	* Copyright (C) IBM Corp. 2006
	6	* Author(s): Michael Holzheu <holzheu@de.ibm.com>
	7	*/
	8
	9	#include <linux/types.h>
	10	#include <linux/errno.h>
	11	#include <linux/fs.h>
	12	#include <linux/namei.h>
	13	#include <linux/vfs.h>
	14	#include <linux/pagemap.h>
	15	#include <linux/gfp.h>
	16	#include <linux/time.h>
	17	#include <linux/parser.h>
	18	#include <linux/sysfs.h>
	19	#include <linux/module.h>
b01af5ba MH	20	#include <linux/seq_file.h>
b01af5ba MH	21	#include <linux/mount.h>
24bbb1fa MH	22	#include <asm/ebcdic.h>
24bbb1fa MH	23	#include "hypfs.h"
24bbb1fa MH	24
	25	#define HYPFS_MAGIC 0x687970 /* ASCII 'hyp' */
	26	#define TMP_SIZE 64 /* size of temporary buffers */
	27
	28	static struct dentry hypfs_create_update_file(struct super_block sb,
	29	struct dentry *dir);
	30
	31	struct hypfs_sb_info {
	32	uid_t uid; /* uid used for files and dirs */
	33	gid_t gid; /* gid used for files and dirs */
	34	struct dentry update_file; / file to trigger update */
	35	time_t last_update; /* last update time in secs since 1970 */
	36	struct mutex lock; /* lock to protect update process */
	37	};
	38
5dfe4c96	39	static const struct file_operations hypfs_file_ops;
24bbb1fa MH	40	static struct file_system_type hypfs_type;
	41	static struct super_operations hypfs_s_ops;
	42
	43	/* start of list of all dentries, which have to be deleted on update */
	44	static struct dentry *hypfs_last_dentry;
	45
	46	static void hypfs_update_update(struct super_block *sb)
	47	{
	48	struct hypfs_sb_info *sb_info = sb->s_fs_info;
	49	struct inode *inode = sb_info->update_file->d_inode;
	50
	51	sb_info->last_update = get_seconds();
	52	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
	53	}
	54
	55	/* directory tree removal functions */
	56
	57	static void hypfs_add_dentry(struct dentry *dentry)
	58	{
	59	dentry->d_fsdata = hypfs_last_dentry;
	60	hypfs_last_dentry = dentry;
	61	}
	62
	63	static void hypfs_remove(struct dentry *dentry)
	64	{
	65	struct dentry *parent;
	66
	67	parent = dentry->d_parent;
	68	if (S_ISDIR(dentry->d_inode->i_mode))
	69	simple_rmdir(parent->d_inode, dentry);
	70	else
	71	simple_unlink(parent->d_inode, dentry);
	72	d_delete(dentry);
	73	dput(dentry);
	74	}
	75
	76	static void hypfs_delete_tree(struct dentry *root)
	77	{
	78	while (hypfs_last_dentry) {
	79	struct dentry *next_dentry;
	80	next_dentry = hypfs_last_dentry->d_fsdata;
	81	hypfs_remove(hypfs_last_dentry);
	82	hypfs_last_dentry = next_dentry;
	83	}
	84	}
	85
	86	static struct inode hypfs_make_inode(struct super_block sb, int mode)
	87	{
	88	struct inode *ret = new_inode(sb);
	89
	90	if (ret) {
	91	struct hypfs_sb_info *hypfs_info = sb->s_fs_info;
	92	ret->i_mode = mode;
	93	ret->i_uid = hypfs_info->uid;
	94	ret->i_gid = hypfs_info->gid;
24bbb1fa MH	95	ret->i_blocks = 0;
	96	ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME;
	97	if (mode & S_IFDIR)
	98	ret->i_nlink = 2;
	99	else
	100	ret->i_nlink = 1;
	101	}
	102	return ret;
	103	}
	104
	105	static void hypfs_drop_inode(struct inode *inode)
	106	{
8e18e294	107	kfree(inode->i_private);
24bbb1fa MH	108	generic_delete_inode(inode);
	109	}
	110
	111	static int hypfs_open(struct inode inode, struct file filp)
	112	{
d20343e7	113	char *data = filp->f_path.dentry->d_inode->i_private;
24bbb1fa MH	114	struct hypfs_sb_info *fs_info;
	115
	116	if (filp->f_mode & FMODE_WRITE) {
	117	if (!(inode->i_mode & S_IWUGO))
	118	return -EACCES;
	119	}
	120	if (filp->f_mode & FMODE_READ) {
	121	if (!(inode->i_mode & S_IRUGO))
	122	return -EACCES;
	123	}
	124
	125	fs_info = inode->i_sb->s_fs_info;
	126	if(data) {
	127	mutex_lock(&fs_info->lock);
	128	filp->private_data = kstrdup(data, GFP_KERNEL);
	129	if (!filp->private_data) {
	130	mutex_unlock(&fs_info->lock);
	131	return -ENOMEM;
	132	}
	133	mutex_unlock(&fs_info->lock);
	134	}
	135	return 0;
	136	}
	137
027445c3 BP	138	static ssize_t hypfs_aio_read(struct kiocb iocb, const struct iovec iov,
027445c3 BP	139	unsigned long nr_segs, loff_t offset)
24bbb1fa MH	140	{
	141	char *data;
	142	size_t len;
	143	struct file *filp = iocb->ki_filp;
027445c3 BP	144	/* XXX: temporary */
	145	char __user *buf = iov[0].iov_base;
	146	size_t count = iov[0].iov_len;
	147
	148	if (nr_segs != 1) {
	149	count = -EINVAL;
	150	goto out;
	151	}
24bbb1fa MH	152
	153	data = filp->private_data;
	154	len = strlen(data);
	155	if (offset > len) {
	156	count = 0;
	157	goto out;
	158	}
	159	if (count > len - offset)
	160	count = len - offset;
	161	if (copy_to_user(buf, data + offset, count)) {
	162	count = -EFAULT;
	163	goto out;
	164	}
	165	iocb->ki_pos += count;
	166	file_accessed(filp);
	167	out:
	168	return count;
	169	}
027445c3 BP	170	static ssize_t hypfs_aio_write(struct kiocb iocb, const struct iovec iov,
027445c3 BP	171	unsigned long nr_segs, loff_t offset)
24bbb1fa MH	172	{
	173	int rc;
	174	struct super_block *sb;
	175	struct hypfs_sb_info *fs_info;
027445c3	176	size_t count = iov_length(iov, nr_segs);
24bbb1fa	177
d20343e7	178	sb = iocb->ki_filp->f_path.dentry->d_inode->i_sb;
24bbb1fa MH	179	fs_info = sb->s_fs_info;
	180	/*
	181	* Currently we only allow one update per second for two reasons:
	182	* 1. diag 204 is VERY expensive
	183	* 2. If several processes do updates in parallel and then read the
	184	* hypfs data, the likelihood of collisions is reduced, if we restrict
	185	* the minimum update interval. A collision occurs, if during the
	186	* data gathering of one process another process triggers an update
	187	* If the first process wants to ensure consistent data, it has
	188	* to restart data collection in this case.
	189	*/
	190	mutex_lock(&fs_info->lock);
	191	if (fs_info->last_update == get_seconds()) {
	192	rc = -EBUSY;
	193	goto out;
	194	}
	195	hypfs_delete_tree(sb->s_root);
31cb4bd3 MH	196	if (MACHINE_IS_VM)
	197	rc = hypfs_vm_create_files(sb, sb->s_root);
	198	else
	199	rc = hypfs_diag_create_files(sb, sb->s_root);
24bbb1fa MH	200	if (rc) {
	201	printk(KERN_ERR "hypfs: Update failed\n");
	202	hypfs_delete_tree(sb->s_root);
	203	goto out;
	204	}
	205	hypfs_update_update(sb);
	206	rc = count;
	207	out:
	208	mutex_unlock(&fs_info->lock);
	209	return rc;
	210	}
	211
	212	static int hypfs_release(struct inode inode, struct file filp)
	213	{
	214	kfree(filp->private_data);
	215	return 0;
	216	}
	217
	218	enum { opt_uid, opt_gid, opt_err };
	219
	220	static match_table_t hypfs_tokens = {
	221	{opt_uid, "uid=%u"},
	222	{opt_gid, "gid=%u"},
	223	{opt_err, NULL}
	224	};
	225
	226	static int hypfs_parse_options(char options, struct super_block sb)
	227	{
	228	char *str;
	229	substring_t args[MAX_OPT_ARGS];
	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	hypfs_info->uid = option;
	245	break;
	246	case opt_gid:
	247	if (match_int(&args[0], &option))
	248	return -EINVAL;
	249	hypfs_info->gid = option;
	250	break;
	251	case opt_err:
	252	default:
	253	printk(KERN_ERR "hypfs: Unrecognized mount option "
	254	"\"%s\" or missing value\n", str);
	255	return -EINVAL;
	256	}
	257	}
	258	return 0;
	259	}
	260
b01af5ba MH	261	static int hypfs_show_options(struct seq_file s, struct vfsmount mnt)
	262	{
	263	struct hypfs_sb_info *hypfs_info = mnt->mnt_sb->s_fs_info;
	264
	265	seq_printf(s, ",uid=%u", hypfs_info->uid);
	266	seq_printf(s, ",gid=%u", hypfs_info->gid);
	267	return 0;
	268	}
	269
24bbb1fa MH	270	static int hypfs_fill_super(struct super_block sb, void data, int silent)
	271	{
	272	struct inode *root_inode;
	273	struct dentry *root_dentry;
	274	int rc = 0;
	275	struct hypfs_sb_info *sbi;
	276
	277	sbi = kzalloc(sizeof(struct hypfs_sb_info), GFP_KERNEL);
	278	if (!sbi)
	279	return -ENOMEM;
	280	mutex_init(&sbi->lock);
	281	sbi->uid = current->uid;
	282	sbi->gid = current->gid;
	283	sb->s_fs_info = sbi;
	284	sb->s_blocksize = PAGE_CACHE_SIZE;
	285	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	286	sb->s_magic = HYPFS_MAGIC;
	287	sb->s_op = &hypfs_s_ops;
	288	if (hypfs_parse_options(data, sb)) {
	289	rc = -EINVAL;
	290	goto err_alloc;
	291	}
	292	root_inode = hypfs_make_inode(sb, S_IFDIR \| 0755);
	293	if (!root_inode) {
	294	rc = -ENOMEM;
	295	goto err_alloc;
	296	}
	297	root_inode->i_op = &simple_dir_inode_operations;
	298	root_inode->i_fop = &simple_dir_operations;
	299	root_dentry = d_alloc_root(root_inode);
	300	if (!root_dentry) {
	301	iput(root_inode);
	302	rc = -ENOMEM;
	303	goto err_alloc;
	304	}
31cb4bd3 MH	305	if (MACHINE_IS_VM)
	306	rc = hypfs_vm_create_files(sb, root_dentry);
	307	else
	308	rc = hypfs_diag_create_files(sb, root_dentry);
24bbb1fa MH	309	if (rc)
	310	goto err_tree;
	311	sbi->update_file = hypfs_create_update_file(sb, root_dentry);
	312	if (IS_ERR(sbi->update_file)) {
	313	rc = PTR_ERR(sbi->update_file);
	314	goto err_tree;
	315	}
	316	hypfs_update_update(sb);
	317	sb->s_root = root_dentry;
	318	return 0;
	319
	320	err_tree:
	321	hypfs_delete_tree(root_dentry);
	322	d_genocide(root_dentry);
	323	dput(root_dentry);
	324	err_alloc:
	325	kfree(sbi);
	326	return rc;
	327	}
	328
a5cf4b9a AM	329	static int hypfs_get_super(struct file_system_type *fst, int flags,
a5cf4b9a AM	330	const char devname, void data, struct vfsmount *mnt)
24bbb1fa	331	{
a5cf4b9a	332	return get_sb_single(fst, flags, data, hypfs_fill_super, mnt);
24bbb1fa MH	333	}
	334
	335	static void hypfs_kill_super(struct super_block *sb)
	336	{
	337	struct hypfs_sb_info *sb_info = sb->s_fs_info;
	338
388c571c MH	339	if (sb->s_root) {
	340	hypfs_delete_tree(sb->s_root);
	341	hypfs_remove(sb_info->update_file);
	342	kfree(sb->s_fs_info);
	343	sb->s_fs_info = NULL;
	344	}
24bbb1fa MH	345	kill_litter_super(sb);
	346	}
	347
	348	static struct dentry hypfs_create_file(struct super_block sb,
	349	struct dentry parent, const char name,
	350	char *data, mode_t mode)
	351	{
	352	struct dentry *dentry;
	353	struct inode *inode;
	354	struct qstr qname;
	355
	356	qname.name = name;
	357	qname.len = strlen(name);
	358	qname.hash = full_name_hash(name, qname.len);
	359	dentry = lookup_one_len(name, parent, strlen(name));
	360	if (IS_ERR(dentry))
	361	return ERR_PTR(-ENOMEM);
	362	inode = hypfs_make_inode(sb, mode);
	363	if (!inode) {
	364	dput(dentry);
	365	return ERR_PTR(-ENOMEM);
	366	}
	367	if (mode & S_IFREG) {
	368	inode->i_fop = &hypfs_file_ops;
	369	if (data)
	370	inode->i_size = strlen(data);
	371	else
	372	inode->i_size = 0;
	373	} else if (mode & S_IFDIR) {
	374	inode->i_op = &simple_dir_inode_operations;
	375	inode->i_fop = &simple_dir_operations;
	376	parent->d_inode->i_nlink++;
	377	} else
	378	BUG();
8e18e294	379	inode->i_private = data;
24bbb1fa MH	380	d_instantiate(dentry, inode);
	381	dget(dentry);
	382	return dentry;
	383	}
	384
	385	struct dentry hypfs_mkdir(struct super_block sb, struct dentry *parent,
	386	const char *name)
	387	{
	388	struct dentry *dentry;
	389
	390	dentry = hypfs_create_file(sb, parent, name, NULL, S_IFDIR \| DIR_MODE);
	391	if (IS_ERR(dentry))
	392	return dentry;
	393	hypfs_add_dentry(dentry);
	394	parent->d_inode->i_nlink++;
	395	return dentry;
	396	}
	397
	398	static struct dentry hypfs_create_update_file(struct super_block sb,
	399	struct dentry *dir)
	400	{
	401	struct dentry *dentry;
	402
	403	dentry = hypfs_create_file(sb, dir, "update", NULL,
	404	S_IFREG \| UPDATE_FILE_MODE);
	405	/*
	406	* We do not put the update file on the 'delete' list with
	407	* hypfs_add_dentry(), since it should not be removed when the tree
	408	* is updated.
	409	*/
	410	return dentry;
	411	}
	412
	413	struct dentry hypfs_create_u64(struct super_block sb, struct dentry *dir,
	414	const char *name, __u64 value)
	415	{
	416	char *buffer;
	417	char tmp[TMP_SIZE];
	418	struct dentry *dentry;
	419
	420	snprintf(tmp, TMP_SIZE, "%lld\n", (unsigned long long int)value);
	421	buffer = kstrdup(tmp, GFP_KERNEL);
	422	if (!buffer)
	423	return ERR_PTR(-ENOMEM);
	424	dentry =
	425	hypfs_create_file(sb, dir, name, buffer, S_IFREG \| REG_FILE_MODE);
	426	if (IS_ERR(dentry)) {
	427	kfree(buffer);
	428	return ERR_PTR(-ENOMEM);
	429	}
	430	hypfs_add_dentry(dentry);
	431	return dentry;
	432	}
	433
	434	struct dentry hypfs_create_str(struct super_block sb, struct dentry *dir,
	435	const char name, char string)
	436	{
	437	char *buffer;
	438	struct dentry *dentry;
	439
	440	buffer = kmalloc(strlen(string) + 2, GFP_KERNEL);
	441	if (!buffer)
	442	return ERR_PTR(-ENOMEM);
	443	sprintf(buffer, "%s\n", string);
444	dentry =
445	hypfs_create_file(sb, dir, name, buffer, S_IFREG \| REG_FILE_MODE);
446	if (IS_ERR(dentry)) {
447	kfree(buffer);
448	return ERR_PTR(-ENOMEM);
449	}
450	hypfs_add_dentry(dentry);
451	return dentry;
452	}
453
5dfe4c96	454	static const struct file_operations hypfs_file_ops = {
24bbb1fa MH	455	.open = hypfs_open,
	456	.release = hypfs_release,
	457	.read = do_sync_read,
	458	.write = do_sync_write,
	459	.aio_read = hypfs_aio_read,
	460	.aio_write = hypfs_aio_write,
	461	};
	462
	463	static struct file_system_type hypfs_type = {
	464	.owner = THIS_MODULE,
	465	.name = "s390_hypfs",
	466	.get_sb = hypfs_get_super,
	467	.kill_sb = hypfs_kill_super
	468	};
	469
	470	static struct super_operations hypfs_s_ops = {
	471	.statfs = simple_statfs,
	472	.drop_inode = hypfs_drop_inode,
b01af5ba	473	.show_options = hypfs_show_options,
24bbb1fa MH	474	};
	475
	476	static decl_subsys(s390, NULL, NULL);
	477
	478	static int __init hypfs_init(void)
	479	{
	480	int rc;
	481
31cb4bd3 MH	482	if (MACHINE_IS_VM) {
	483	if (hypfs_vm_init())
	484	/* no diag 2fc, just exit */
	485	return -ENODATA;
	486	} else {
	487	if (hypfs_diag_init()) {
	488	rc = -ENODATA;
	489	goto fail_diag;
	490	}
24bbb1fa	491	}
0b0bb3c6	492	kobj_set_kset_s(&s390_subsys, hypervisor_subsys);
24bbb1fa MH	493	rc = subsystem_register(&s390_subsys);
	494	if (rc)
	495	goto fail_sysfs;
	496	rc = register_filesystem(&hypfs_type);
	497	if (rc)
	498	goto fail_filesystem;
	499	return 0;
	500
	501	fail_filesystem:
	502	subsystem_unregister(&s390_subsys);
	503	fail_sysfs:
31cb4bd3 MH	504	if (!MACHINE_IS_VM)
31cb4bd3 MH	505	hypfs_diag_exit();
24bbb1fa MH	506	fail_diag:
	507	printk(KERN_ERR "hypfs: Initialization failed with rc = %i.\n", rc);
	508	return rc;
	509	}
	510
	511	static void __exit hypfs_exit(void)
	512	{
31cb4bd3 MH	513	if (!MACHINE_IS_VM)
31cb4bd3 MH	514	hypfs_diag_exit();
24bbb1fa MH	515	unregister_filesystem(&hypfs_type);
	516	subsystem_unregister(&s390_subsys);
	517	}
	518
	519	module_init(hypfs_init)
	520	module_exit(hypfs_exit)
	521
	522	MODULE_LICENSE("GPL");
	523	MODULE_AUTHOR("Michael Holzheu <holzheu@de.ibm.com>");
	524	MODULE_DESCRIPTION("s390 Hypervisor Filesystem");