[mirror_ubuntu-artful-kernel.git] / fs / fuse / inode.c

/*
  FUSE: Filesystem in Userspace
  Copyright (C) 2001-2005  Miklos Szeredi <miklos@szeredi.hu>

  This program can be distributed under the terms of the GNU GPL.
  See the file COPYING.
*/

#include "fuse_i.h"

#include <linux/pagemap.h>
#include <linux/slab.h>
#include <linux/file.h>
#include <linux/mount.h>
#include <linux/seq_file.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/parser.h>
#include <linux/statfs.h>

MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
MODULE_DESCRIPTION("Filesystem in Userspace");
MODULE_LICENSE("GPL");

spinlock_t fuse_lock;
static kmem_cache_t *fuse_inode_cachep;

#define FUSE_SUPER_MAGIC 0x65735546

struct fuse_mount_data {
	int fd;
	unsigned rootmode;
	unsigned user_id;
	unsigned flags;
	unsigned max_read;
};

static struct inode *fuse_alloc_inode(struct super_block *sb)
{
	struct inode *inode;
	struct fuse_inode *fi;

	inode = kmem_cache_alloc(fuse_inode_cachep, SLAB_KERNEL);
	if (!inode)
		return NULL;

	fi = get_fuse_inode(inode);
	fi->i_time = jiffies - 1;
	fi->nodeid = 0;
	fi->nlookup = 0;
	fi->forget_req = fuse_request_alloc();
	if (!fi->forget_req) {
		kmem_cache_free(fuse_inode_cachep, inode);
		return NULL;
	}

	return inode;
}

static void fuse_destroy_inode(struct inode *inode)
{
	struct fuse_inode *fi = get_fuse_inode(inode);
	if (fi->forget_req)
		fuse_request_free(fi->forget_req);
	kmem_cache_free(fuse_inode_cachep, inode);
}

static void fuse_read_inode(struct inode *inode)
{
	/* No op */
}

void fuse_send_forget(struct fuse_conn *fc, struct fuse_req *req,
		      unsigned long nodeid, u64 nlookup)
{
	struct fuse_forget_in *inarg = &req->misc.forget_in;
	inarg->nlookup = nlookup;
	req->in.h.opcode = FUSE_FORGET;
	req->in.h.nodeid = nodeid;
	req->in.numargs = 1;
	req->in.args[0].size = sizeof(struct fuse_forget_in);
	req->in.args[0].value = inarg;
	request_send_noreply(fc, req);
}

static void fuse_clear_inode(struct inode *inode)
{
	if (inode->i_sb->s_flags & MS_ACTIVE) {
		struct fuse_conn *fc = get_fuse_conn(inode);
		struct fuse_inode *fi = get_fuse_inode(inode);
		fuse_send_forget(fc, fi->forget_req, fi->nodeid, fi->nlookup);
		fi->forget_req = NULL;
	}
}

void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr)
{
	if (S_ISREG(inode->i_mode) && i_size_read(inode) != attr->size)
		invalidate_inode_pages(inode->i_mapping);

	inode->i_ino     = attr->ino;
	inode->i_mode    = (inode->i_mode & S_IFMT) + (attr->mode & 07777);
	inode->i_nlink   = attr->nlink;
	inode->i_uid     = attr->uid;
	inode->i_gid     = attr->gid;
	i_size_write(inode, attr->size);
	inode->i_blksize = PAGE_CACHE_SIZE;
	inode->i_blocks  = attr->blocks;
	inode->i_atime.tv_sec   = attr->atime;
	inode->i_atime.tv_nsec  = attr->atimensec;
	inode->i_mtime.tv_sec   = attr->mtime;
	inode->i_mtime.tv_nsec  = attr->mtimensec;
	inode->i_ctime.tv_sec   = attr->ctime;
	inode->i_ctime.tv_nsec  = attr->ctimensec;
}

static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr)
{
	inode->i_mode = attr->mode & S_IFMT;
	i_size_write(inode, attr->size);
	if (S_ISREG(inode->i_mode)) {
		fuse_init_common(inode);
		fuse_init_file_inode(inode);
	} else if (S_ISDIR(inode->i_mode))
		fuse_init_dir(inode);
	else if (S_ISLNK(inode->i_mode))
		fuse_init_symlink(inode);
	else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
		 S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
		fuse_init_common(inode);
		init_special_inode(inode, inode->i_mode,
				   new_decode_dev(attr->rdev));
	} else {
		/* Don't let user create weird files */
		inode->i_mode = S_IFREG;
		fuse_init_common(inode);
		fuse_init_file_inode(inode);
	}
}

static int fuse_inode_eq(struct inode *inode, void *_nodeidp)
{
	unsigned long nodeid = *(unsigned long *) _nodeidp;
	if (get_node_id(inode) == nodeid)
		return 1;
	else
		return 0;
}

static int fuse_inode_set(struct inode *inode, void *_nodeidp)
{
	unsigned long nodeid = *(unsigned long *) _nodeidp;
	get_fuse_inode(inode)->nodeid = nodeid;
	return 0;
}

struct inode *fuse_iget(struct super_block *sb, unsigned long nodeid,
			int generation, struct fuse_attr *attr)
{
	struct inode *inode;
	struct fuse_inode *fi;
	struct fuse_conn *fc = get_fuse_conn_super(sb);
	int retried = 0;

 retry:
	inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid);
	if (!inode)
		return NULL;

	if ((inode->i_state & I_NEW)) {
		inode->i_generation = generation;
		inode->i_data.backing_dev_info = &fc->bdi;
		fuse_init_inode(inode, attr);
		unlock_new_inode(inode);
	} else if ((inode->i_mode ^ attr->mode) & S_IFMT) {
		BUG_ON(retried);
		/* Inode has changed type, any I/O on the old should fail */
		make_bad_inode(inode);
		iput(inode);
		retried = 1;
		goto retry;
	}

	fi = get_fuse_inode(inode);
	fi->nlookup ++;
	fuse_change_attributes(inode, attr);
	return inode;
}

static void fuse_put_super(struct super_block *sb)
{
	struct fuse_conn *fc = get_fuse_conn_super(sb);

	down_write(&fc->sbput_sem);
	while (!list_empty(&fc->background))
		fuse_release_background(list_entry(fc->background.next,
						   struct fuse_req, bg_entry));

	spin_lock(&fuse_lock);
	fc->mounted = 0;
	fc->user_id = 0;
	fc->flags = 0;
	/* Flush all readers on this fs */
	wake_up_all(&fc->waitq);
	up_write(&fc->sbput_sem);
	fuse_release_conn(fc);
	spin_unlock(&fuse_lock);
}

static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr)
{
	stbuf->f_type    = FUSE_SUPER_MAGIC;
	stbuf->f_bsize   = attr->bsize;
	stbuf->f_blocks  = attr->blocks;
	stbuf->f_bfree   = attr->bfree;
	stbuf->f_bavail  = attr->bavail;
	stbuf->f_files   = attr->files;
	stbuf->f_ffree   = attr->ffree;
	stbuf->f_namelen = attr->namelen;
	/* fsid is left zero */
}

static int fuse_statfs(struct super_block *sb, struct kstatfs *buf)
{
	struct fuse_conn *fc = get_fuse_conn_super(sb);
	struct fuse_req *req;
	struct fuse_statfs_out outarg;
	int err;

        req = fuse_get_request(fc);
	if (!req)
		return -ERESTARTSYS;

	req->in.numargs = 0;
	req->in.h.opcode = FUSE_STATFS;
	req->out.numargs = 1;
	req->out.args[0].size = sizeof(outarg);
	req->out.args[0].value = &outarg;
	request_send(fc, req);
	err = req->out.h.error;
	if (!err)
		convert_fuse_statfs(buf, &outarg.st);
	fuse_put_request(fc, req);
	return err;
}

enum {
	OPT_FD,
	OPT_ROOTMODE,
	OPT_USER_ID,
	OPT_DEFAULT_PERMISSIONS,
	OPT_ALLOW_OTHER,
	OPT_KERNEL_CACHE,
	OPT_MAX_READ,
	OPT_ERR
};

static match_table_t tokens = {
	{OPT_FD,			"fd=%u"},
	{OPT_ROOTMODE,			"rootmode=%o"},
	{OPT_USER_ID,			"user_id=%u"},
	{OPT_DEFAULT_PERMISSIONS,	"default_permissions"},
	{OPT_ALLOW_OTHER,		"allow_other"},
	{OPT_KERNEL_CACHE,		"kernel_cache"},
	{OPT_MAX_READ,			"max_read=%u"},
	{OPT_ERR,			NULL}
};

static int parse_fuse_opt(char *opt, struct fuse_mount_data *d)
{
	char *p;
	memset(d, 0, sizeof(struct fuse_mount_data));
	d->fd = -1;
	d->max_read = ~0;

	while ((p = strsep(&opt, ",")) != NULL) {
		int token;
		int value;
		substring_t args[MAX_OPT_ARGS];
		if (!*p)
			continue;

		token = match_token(p, tokens, args);
		switch (token) {
		case OPT_FD:
			if (match_int(&args[0], &value))
				return 0;
			d->fd = value;
			break;

		case OPT_ROOTMODE:
			if (match_octal(&args[0], &value))
				return 0;
			d->rootmode = value;
			break;

		case OPT_USER_ID:
			if (match_int(&args[0], &value))
				return 0;
			d->user_id = value;
			break;

		case OPT_DEFAULT_PERMISSIONS:
			d->flags |= FUSE_DEFAULT_PERMISSIONS;
			break;

		case OPT_ALLOW_OTHER:
			d->flags |= FUSE_ALLOW_OTHER;
			break;

		case OPT_KERNEL_CACHE:
			d->flags |= FUSE_KERNEL_CACHE;
			break;

		case OPT_MAX_READ:
			if (match_int(&args[0], &value))
				return 0;
			d->max_read = value;
			break;

		default:
			return 0;
		}
	}
	if (d->fd == -1)
		return 0;

	return 1;
}

static int fuse_show_options(struct seq_file *m, struct vfsmount *mnt)
{
	struct fuse_conn *fc = get_fuse_conn_super(mnt->mnt_sb);

	seq_printf(m, ",user_id=%u", fc->user_id);
	if (fc->flags & FUSE_DEFAULT_PERMISSIONS)
		seq_puts(m, ",default_permissions");
	if (fc->flags & FUSE_ALLOW_OTHER)
		seq_puts(m, ",allow_other");
	if (fc->flags & FUSE_KERNEL_CACHE)
		seq_puts(m, ",kernel_cache");
	if (fc->max_read != ~0)
		seq_printf(m, ",max_read=%u", fc->max_read);
	return 0;
}

static void free_conn(struct fuse_conn *fc)
{
	while (!list_empty(&fc->unused_list)) {
		struct fuse_req *req;
		req = list_entry(fc->unused_list.next, struct fuse_req, list);
		list_del(&req->list);
		fuse_request_free(req);
	}
	kfree(fc);
}

/* Must be called with the fuse lock held */
void fuse_release_conn(struct fuse_conn *fc)
{
	fc->count--;
	if (!fc->count)
		free_conn(fc);
}

static struct fuse_conn *new_conn(void)
{
	struct fuse_conn *fc;

	fc = kmalloc(sizeof(*fc), GFP_KERNEL);
	if (fc != NULL) {
		int i;
		memset(fc, 0, sizeof(*fc));
		init_waitqueue_head(&fc->waitq);
		INIT_LIST_HEAD(&fc->pending);
		INIT_LIST_HEAD(&fc->processing);
		INIT_LIST_HEAD(&fc->unused_list);
		INIT_LIST_HEAD(&fc->background);
		sema_init(&fc->outstanding_sem, 0);
		init_rwsem(&fc->sbput_sem);
		for (i = 0; i < FUSE_MAX_OUTSTANDING; i++) {
			struct fuse_req *req = fuse_request_alloc();
			if (!req) {
				free_conn(fc);
				return NULL;
			}
			list_add(&req->list, &fc->unused_list);
		}
		fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
		fc->bdi.unplug_io_fn = default_unplug_io_fn;
		fc->reqctr = 0;
	}
	return fc;
}

static struct fuse_conn *get_conn(struct file *file, struct super_block *sb)
{
	struct fuse_conn *fc;

	if (file->f_op != &fuse_dev_operations)
		return ERR_PTR(-EINVAL);
	fc = new_conn();
	if (fc == NULL)
		return ERR_PTR(-ENOMEM);
	spin_lock(&fuse_lock);
	if (file->private_data) {
		free_conn(fc);
		fc = ERR_PTR(-EINVAL);
	} else {
		file->private_data = fc;
		*get_fuse_conn_super_p(sb) = fc;
		fc->mounted = 1;
		fc->connected = 1;
		fc->count = 2;
	}
	spin_unlock(&fuse_lock);
	return fc;
}

static struct inode *get_root_inode(struct super_block *sb, unsigned mode)
{
	struct fuse_attr attr;
	memset(&attr, 0, sizeof(attr));

	attr.mode = mode;
	attr.ino = FUSE_ROOT_ID;
	return fuse_iget(sb, 1, 0, &attr);
}

static struct super_operations fuse_super_operations = {
	.alloc_inode    = fuse_alloc_inode,
	.destroy_inode  = fuse_destroy_inode,
	.read_inode	= fuse_read_inode,
	.clear_inode	= fuse_clear_inode,
	.put_super	= fuse_put_super,
	.statfs		= fuse_statfs,
	.show_options	= fuse_show_options,
};

static int fuse_fill_super(struct super_block *sb, void *data, int silent)
{
	struct fuse_conn *fc;
	struct inode *root;
	struct fuse_mount_data d;
	struct file *file;
	int err;

	if (!parse_fuse_opt((char *) data, &d))
		return -EINVAL;

	sb->s_blocksize = PAGE_CACHE_SIZE;
	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	sb->s_magic = FUSE_SUPER_MAGIC;
	sb->s_op = &fuse_super_operations;
	sb->s_maxbytes = MAX_LFS_FILESIZE;

	file = fget(d.fd);
	if (!file)
		return -EINVAL;

	fc = get_conn(file, sb);
	fput(file);
	if (IS_ERR(fc))
		return PTR_ERR(fc);

	fc->flags = d.flags;
	fc->user_id = d.user_id;
	fc->max_read = d.max_read;
	if (fc->max_read / PAGE_CACHE_SIZE < fc->bdi.ra_pages)
		fc->bdi.ra_pages = fc->max_read / PAGE_CACHE_SIZE;

	err = -ENOMEM;
	root = get_root_inode(sb, d.rootmode);
	if (root == NULL)
		goto err;

	sb->s_root = d_alloc_root(root);
	if (!sb->s_root) {
		iput(root);
		goto err;
	}
	fuse_send_init(fc);
	return 0;

 err:
	spin_lock(&fuse_lock);
	fuse_release_conn(fc);
	spin_unlock(&fuse_lock);
	return err;
}

static struct super_block *fuse_get_sb(struct file_system_type *fs_type,
				       int flags, const char *dev_name,
				       void *raw_data)
{
	return get_sb_nodev(fs_type, flags, raw_data, fuse_fill_super);
}

static struct file_system_type fuse_fs_type = {
	.owner		= THIS_MODULE,
	.name		= "fuse",
	.get_sb		= fuse_get_sb,
	.kill_sb	= kill_anon_super,
};

static void fuse_inode_init_once(void *foo, kmem_cache_t *cachep,
				 unsigned long flags)
{
	struct inode * inode = foo;

	if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
	    SLAB_CTOR_CONSTRUCTOR)
		inode_init_once(inode);
}

static int __init fuse_fs_init(void)
{
	int err;

	err = register_filesystem(&fuse_fs_type);
	if (err)
		printk("fuse: failed to register filesystem\n");
	else {
		fuse_inode_cachep = kmem_cache_create("fuse_inode",
						      sizeof(struct fuse_inode),
						      0, SLAB_HWCACHE_ALIGN,
						      fuse_inode_init_once, NULL);
		if (!fuse_inode_cachep) {
			unregister_filesystem(&fuse_fs_type);
			err = -ENOMEM;
		}
	}

	return err;
}

static void fuse_fs_cleanup(void)
{
	unregister_filesystem(&fuse_fs_type);
	kmem_cache_destroy(fuse_inode_cachep);
}

static int __init fuse_init(void)
{
	int res;

	printk("fuse init (API version %i.%i)\n",
	       FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);

	spin_lock_init(&fuse_lock);
	res = fuse_fs_init();
	if (res)
		goto err;

	res = fuse_dev_init();
	if (res)
		goto err_fs_cleanup;

	return 0;

 err_fs_cleanup:
	fuse_fs_cleanup();
 err:
	return res;
}

static void __exit fuse_exit(void)
{
	printk(KERN_DEBUG "fuse exit\n");

	fuse_fs_cleanup();
	fuse_dev_cleanup();
}

module_init(fuse_init);
module_exit(fuse_exit);
Commit	Line	Data
d8a5ba45 MS	1	/*
	2	FUSE: Filesystem in Userspace
	3	Copyright (C) 2001-2005 Miklos Szeredi <miklos@szeredi.hu>
	4
	5	This program can be distributed under the terms of the GNU GPL.
	6	See the file COPYING.
	7	*/
	8
	9	#include "fuse_i.h"
	10
	11	#include <linux/pagemap.h>
	12	#include <linux/slab.h>
	13	#include <linux/file.h>
	14	#include <linux/mount.h>
	15	#include <linux/seq_file.h>
	16	#include <linux/init.h>
	17	#include <linux/module.h>
d8a5ba45 MS	18	#include <linux/parser.h>
	19	#include <linux/statfs.h>
	20
	21	MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
	22	MODULE_DESCRIPTION("Filesystem in Userspace");
	23	MODULE_LICENSE("GPL");
	24
	25	spinlock_t fuse_lock;
	26	static kmem_cache_t *fuse_inode_cachep;
d8a5ba45 MS	27
	28	#define FUSE_SUPER_MAGIC 0x65735546
	29
	30	struct fuse_mount_data {
	31	int fd;
	32	unsigned rootmode;
	33	unsigned user_id;
1e9a4ed9	34	unsigned flags;
db50b96c	35	unsigned max_read;
d8a5ba45 MS	36	};
	37
	38	static struct inode fuse_alloc_inode(struct super_block sb)
	39	{
	40	struct inode *inode;
	41	struct fuse_inode *fi;
	42
	43	inode = kmem_cache_alloc(fuse_inode_cachep, SLAB_KERNEL);
	44	if (!inode)
	45	return NULL;
	46
	47	fi = get_fuse_inode(inode);
	48	fi->i_time = jiffies - 1;
	49	fi->nodeid = 0;
9e6268db	50	fi->nlookup = 0;
e5e5558e MS	51	fi->forget_req = fuse_request_alloc();
	52	if (!fi->forget_req) {
	53	kmem_cache_free(fuse_inode_cachep, inode);
	54	return NULL;
	55	}
d8a5ba45 MS	56
	57	return inode;
	58	}
	59
	60	static void fuse_destroy_inode(struct inode *inode)
	61	{
e5e5558e MS	62	struct fuse_inode *fi = get_fuse_inode(inode);
	63	if (fi->forget_req)
	64	fuse_request_free(fi->forget_req);
d8a5ba45 MS	65	kmem_cache_free(fuse_inode_cachep, inode);
	66	}
	67
	68	static void fuse_read_inode(struct inode *inode)
	69	{
	70	/* No op */
	71	}
	72
e5e5558e	73	void fuse_send_forget(struct fuse_conn fc, struct fuse_req req,
9e6268db	74	unsigned long nodeid, u64 nlookup)
e5e5558e MS	75	{
e5e5558e MS	76	struct fuse_forget_in *inarg = &req->misc.forget_in;
9e6268db	77	inarg->nlookup = nlookup;
e5e5558e MS	78	req->in.h.opcode = FUSE_FORGET;
	79	req->in.h.nodeid = nodeid;
	80	req->in.numargs = 1;
	81	req->in.args[0].size = sizeof(struct fuse_forget_in);
	82	req->in.args[0].value = inarg;
	83	request_send_noreply(fc, req);
	84	}
	85
d8a5ba45 MS	86	static void fuse_clear_inode(struct inode *inode)
d8a5ba45 MS	87	{
1e9a4ed9 MS	88	if (inode->i_sb->s_flags & MS_ACTIVE) {
1e9a4ed9 MS	89	struct fuse_conn *fc = get_fuse_conn(inode);
e5e5558e	90	struct fuse_inode *fi = get_fuse_inode(inode);
9e6268db	91	fuse_send_forget(fc, fi->forget_req, fi->nodeid, fi->nlookup);
e5e5558e MS	92	fi->forget_req = NULL;
e5e5558e MS	93	}
d8a5ba45 MS	94	}
	95
	96	void fuse_change_attributes(struct inode inode, struct fuse_attr attr)
	97	{
	98	if (S_ISREG(inode->i_mode) && i_size_read(inode) != attr->size)
	99	invalidate_inode_pages(inode->i_mapping);
	100
	101	inode->i_ino = attr->ino;
	102	inode->i_mode = (inode->i_mode & S_IFMT) + (attr->mode & 07777);
	103	inode->i_nlink = attr->nlink;
	104	inode->i_uid = attr->uid;
	105	inode->i_gid = attr->gid;
	106	i_size_write(inode, attr->size);
	107	inode->i_blksize = PAGE_CACHE_SIZE;
	108	inode->i_blocks = attr->blocks;
	109	inode->i_atime.tv_sec = attr->atime;
	110	inode->i_atime.tv_nsec = attr->atimensec;
	111	inode->i_mtime.tv_sec = attr->mtime;
	112	inode->i_mtime.tv_nsec = attr->mtimensec;
	113	inode->i_ctime.tv_sec = attr->ctime;
	114	inode->i_ctime.tv_nsec = attr->ctimensec;
	115	}
	116
	117	static void fuse_init_inode(struct inode inode, struct fuse_attr attr)
	118	{
	119	inode->i_mode = attr->mode & S_IFMT;
	120	i_size_write(inode, attr->size);
e5e5558e MS	121	if (S_ISREG(inode->i_mode)) {
e5e5558e MS	122	fuse_init_common(inode);
b6aeaded	123	fuse_init_file_inode(inode);
e5e5558e MS	124	} else if (S_ISDIR(inode->i_mode))
	125	fuse_init_dir(inode);
	126	else if (S_ISLNK(inode->i_mode))
	127	fuse_init_symlink(inode);
	128	else if (S_ISCHR(inode->i_mode) \|\| S_ISBLK(inode->i_mode) \|\|
	129	S_ISFIFO(inode->i_mode) \|\| S_ISSOCK(inode->i_mode)) {
	130	fuse_init_common(inode);
	131	init_special_inode(inode, inode->i_mode,
	132	new_decode_dev(attr->rdev));
	133	} else {
	134	/* Don't let user create weird files */
	135	inode->i_mode = S_IFREG;
	136	fuse_init_common(inode);
b6aeaded	137	fuse_init_file_inode(inode);
e5e5558e	138	}
d8a5ba45 MS	139	}
	140
	141	static int fuse_inode_eq(struct inode inode, void _nodeidp)
	142	{
	143	unsigned long nodeid = (unsigned long ) _nodeidp;
	144	if (get_node_id(inode) == nodeid)
	145	return 1;
	146	else
	147	return 0;
	148	}
	149
	150	static int fuse_inode_set(struct inode inode, void _nodeidp)
	151	{
	152	unsigned long nodeid = (unsigned long ) _nodeidp;
	153	get_fuse_inode(inode)->nodeid = nodeid;
	154	return 0;
	155	}
	156
	157	struct inode fuse_iget(struct super_block sb, unsigned long nodeid,
9e6268db	158	int generation, struct fuse_attr *attr)
d8a5ba45 MS	159	{
d8a5ba45 MS	160	struct inode *inode;
9e6268db	161	struct fuse_inode *fi;
d8a5ba45 MS	162	struct fuse_conn *fc = get_fuse_conn_super(sb);
	163	int retried = 0;
	164
	165	retry:
	166	inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid);
	167	if (!inode)
	168	return NULL;
	169
	170	if ((inode->i_state & I_NEW)) {
	171	inode->i_generation = generation;
	172	inode->i_data.backing_dev_info = &fc->bdi;
	173	fuse_init_inode(inode, attr);
	174	unlock_new_inode(inode);
	175	} else if ((inode->i_mode ^ attr->mode) & S_IFMT) {
	176	BUG_ON(retried);
	177	/* Inode has changed type, any I/O on the old should fail */
	178	make_bad_inode(inode);
	179	iput(inode);
	180	retried = 1;
	181	goto retry;
	182	}
	183
9e6268db MS	184	fi = get_fuse_inode(inode);
9e6268db MS	185	fi->nlookup ++;
d8a5ba45	186	fuse_change_attributes(inode, attr);
d8a5ba45 MS	187	return inode;
	188	}
	189
	190	static void fuse_put_super(struct super_block *sb)
	191	{
	192	struct fuse_conn *fc = get_fuse_conn_super(sb);
	193
1e9a4ed9 MS	194	down_write(&fc->sbput_sem);
	195	while (!list_empty(&fc->background))
	196	fuse_release_background(list_entry(fc->background.next,
	197	struct fuse_req, bg_entry));
	198
d8a5ba45	199	spin_lock(&fuse_lock);
1e9a4ed9	200	fc->mounted = 0;
d8a5ba45	201	fc->user_id = 0;
1e9a4ed9	202	fc->flags = 0;
334f485d MS	203	/* Flush all readers on this fs */
334f485d MS	204	wake_up_all(&fc->waitq);
1e9a4ed9	205	up_write(&fc->sbput_sem);
d8a5ba45	206	fuse_release_conn(fc);
d8a5ba45 MS	207	spin_unlock(&fuse_lock);
	208	}
	209
e5e5558e MS	210	static void convert_fuse_statfs(struct kstatfs stbuf, struct fuse_kstatfs attr)
	211	{
	212	stbuf->f_type = FUSE_SUPER_MAGIC;
	213	stbuf->f_bsize = attr->bsize;
	214	stbuf->f_blocks = attr->blocks;
	215	stbuf->f_bfree = attr->bfree;
	216	stbuf->f_bavail = attr->bavail;
	217	stbuf->f_files = attr->files;
	218	stbuf->f_ffree = attr->ffree;
	219	stbuf->f_namelen = attr->namelen;
	220	/* fsid is left zero */
	221	}
	222
	223	static int fuse_statfs(struct super_block sb, struct kstatfs buf)
	224	{
	225	struct fuse_conn *fc = get_fuse_conn_super(sb);
	226	struct fuse_req *req;
	227	struct fuse_statfs_out outarg;
	228	int err;
	229
	230	req = fuse_get_request(fc);
	231	if (!req)
	232	return -ERESTARTSYS;
	233
	234	req->in.numargs = 0;
	235	req->in.h.opcode = FUSE_STATFS;
	236	req->out.numargs = 1;
	237	req->out.args[0].size = sizeof(outarg);
	238	req->out.args[0].value = &outarg;
	239	request_send(fc, req);
	240	err = req->out.h.error;
	241	if (!err)
	242	convert_fuse_statfs(buf, &outarg.st);
	243	fuse_put_request(fc, req);
	244	return err;
	245	}
	246
d8a5ba45 MS	247	enum {
	248	OPT_FD,
	249	OPT_ROOTMODE,
	250	OPT_USER_ID,
	251	OPT_DEFAULT_PERMISSIONS,
	252	OPT_ALLOW_OTHER,
d8a5ba45	253	OPT_KERNEL_CACHE,
db50b96c	254	OPT_MAX_READ,
d8a5ba45 MS	255	OPT_ERR
	256	};
	257
	258	static match_table_t tokens = {
	259	{OPT_FD, "fd=%u"},
	260	{OPT_ROOTMODE, "rootmode=%o"},
	261	{OPT_USER_ID, "user_id=%u"},
	262	{OPT_DEFAULT_PERMISSIONS, "default_permissions"},
	263	{OPT_ALLOW_OTHER, "allow_other"},
d8a5ba45	264	{OPT_KERNEL_CACHE, "kernel_cache"},
db50b96c	265	{OPT_MAX_READ, "max_read=%u"},
d8a5ba45 MS	266	{OPT_ERR, NULL}
	267	};
	268
	269	static int parse_fuse_opt(char opt, struct fuse_mount_data d)
	270	{
	271	char *p;
	272	memset(d, 0, sizeof(struct fuse_mount_data));
	273	d->fd = -1;
db50b96c	274	d->max_read = ~0;
d8a5ba45 MS	275
	276	while ((p = strsep(&opt, ",")) != NULL) {
	277	int token;
	278	int value;
	279	substring_t args[MAX_OPT_ARGS];
	280	if (!*p)
	281	continue;
	282
	283	token = match_token(p, tokens, args);
	284	switch (token) {
	285	case OPT_FD:
	286	if (match_int(&args[0], &value))
	287	return 0;
	288	d->fd = value;
	289	break;
	290
	291	case OPT_ROOTMODE:
	292	if (match_octal(&args[0], &value))
	293	return 0;
	294	d->rootmode = value;
	295	break;
	296
	297	case OPT_USER_ID:
	298	if (match_int(&args[0], &value))
	299	return 0;
	300	d->user_id = value;
	301	break;
	302
1e9a4ed9 MS	303	case OPT_DEFAULT_PERMISSIONS:
	304	d->flags \|= FUSE_DEFAULT_PERMISSIONS;
	305	break;
	306
	307	case OPT_ALLOW_OTHER:
	308	d->flags \|= FUSE_ALLOW_OTHER;
	309	break;
	310
	311	case OPT_KERNEL_CACHE:
	312	d->flags \|= FUSE_KERNEL_CACHE;
	313	break;
	314
db50b96c MS	315	case OPT_MAX_READ:
	316	if (match_int(&args[0], &value))
	317	return 0;
	318	d->max_read = value;
	319	break;
	320
d8a5ba45 MS	321	default:
	322	return 0;
	323	}
	324	}
	325	if (d->fd == -1)
	326	return 0;
	327
	328	return 1;
	329	}
	330
	331	static int fuse_show_options(struct seq_file m, struct vfsmount mnt)
	332	{
	333	struct fuse_conn *fc = get_fuse_conn_super(mnt->mnt_sb);
	334
	335	seq_printf(m, ",user_id=%u", fc->user_id);
1e9a4ed9 MS	336	if (fc->flags & FUSE_DEFAULT_PERMISSIONS)
	337	seq_puts(m, ",default_permissions");
	338	if (fc->flags & FUSE_ALLOW_OTHER)
	339	seq_puts(m, ",allow_other");
	340	if (fc->flags & FUSE_KERNEL_CACHE)
	341	seq_puts(m, ",kernel_cache");
db50b96c MS	342	if (fc->max_read != ~0)
db50b96c MS	343	seq_printf(m, ",max_read=%u", fc->max_read);
d8a5ba45 MS	344	return 0;
	345	}
	346
334f485d	347	static void free_conn(struct fuse_conn *fc)
d8a5ba45	348	{
334f485d MS	349	while (!list_empty(&fc->unused_list)) {
	350	struct fuse_req *req;
	351	req = list_entry(fc->unused_list.next, struct fuse_req, list);
	352	list_del(&req->list);
	353	fuse_request_free(req);
	354	}
d8a5ba45 MS	355	kfree(fc);
	356	}
	357
334f485d MS	358	/* Must be called with the fuse lock held */
	359	void fuse_release_conn(struct fuse_conn *fc)
	360	{
1e9a4ed9 MS	361	fc->count--;
1e9a4ed9 MS	362	if (!fc->count)
334f485d MS	363	free_conn(fc);
	364	}
	365
d8a5ba45 MS	366	static struct fuse_conn *new_conn(void)
	367	{
	368	struct fuse_conn *fc;
	369
	370	fc = kmalloc(sizeof(*fc), GFP_KERNEL);
	371	if (fc != NULL) {
334f485d	372	int i;
d8a5ba45	373	memset(fc, 0, sizeof(*fc));
334f485d MS	374	init_waitqueue_head(&fc->waitq);
	375	INIT_LIST_HEAD(&fc->pending);
	376	INIT_LIST_HEAD(&fc->processing);
	377	INIT_LIST_HEAD(&fc->unused_list);
1e9a4ed9	378	INIT_LIST_HEAD(&fc->background);
334f485d	379	sema_init(&fc->outstanding_sem, 0);
1e9a4ed9	380	init_rwsem(&fc->sbput_sem);
334f485d MS	381	for (i = 0; i < FUSE_MAX_OUTSTANDING; i++) {
	382	struct fuse_req *req = fuse_request_alloc();
	383	if (!req) {
	384	free_conn(fc);
	385	return NULL;
	386	}
	387	list_add(&req->list, &fc->unused_list);
	388	}
d8a5ba45 MS	389	fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
d8a5ba45 MS	390	fc->bdi.unplug_io_fn = default_unplug_io_fn;
334f485d	391	fc->reqctr = 0;
d8a5ba45 MS	392	}
	393	return fc;
	394	}
	395
	396	static struct fuse_conn get_conn(struct file file, struct super_block *sb)
	397	{
	398	struct fuse_conn *fc;
	399
334f485d MS	400	if (file->f_op != &fuse_dev_operations)
334f485d MS	401	return ERR_PTR(-EINVAL);
d8a5ba45 MS	402	fc = new_conn();
d8a5ba45 MS	403	if (fc == NULL)
334f485d	404	return ERR_PTR(-ENOMEM);
d8a5ba45	405	spin_lock(&fuse_lock);
334f485d MS	406	if (file->private_data) {
	407	free_conn(fc);
	408	fc = ERR_PTR(-EINVAL);
	409	} else {
	410	file->private_data = fc;
1e9a4ed9 MS	411	*get_fuse_conn_super_p(sb) = fc;
	412	fc->mounted = 1;
	413	fc->connected = 1;
	414	fc->count = 2;
334f485d	415	}
d8a5ba45 MS	416	spin_unlock(&fuse_lock);
	417	return fc;
	418	}
	419
	420	static struct inode get_root_inode(struct super_block sb, unsigned mode)
	421	{
	422	struct fuse_attr attr;
	423	memset(&attr, 0, sizeof(attr));
	424
	425	attr.mode = mode;
	426	attr.ino = FUSE_ROOT_ID;
9e6268db	427	return fuse_iget(sb, 1, 0, &attr);
d8a5ba45 MS	428	}
	429
	430	static struct super_operations fuse_super_operations = {
	431	.alloc_inode = fuse_alloc_inode,
	432	.destroy_inode = fuse_destroy_inode,
	433	.read_inode = fuse_read_inode,
	434	.clear_inode = fuse_clear_inode,
	435	.put_super = fuse_put_super,
e5e5558e	436	.statfs = fuse_statfs,
d8a5ba45 MS	437	.show_options = fuse_show_options,
	438	};
	439
d8a5ba45 MS	440	static int fuse_fill_super(struct super_block sb, void data, int silent)
	441	{
	442	struct fuse_conn *fc;
	443	struct inode *root;
	444	struct fuse_mount_data d;
	445	struct file *file;
	446	int err;
	447
	448	if (!parse_fuse_opt((char *) data, &d))
	449	return -EINVAL;
	450
	451	sb->s_blocksize = PAGE_CACHE_SIZE;
	452	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	453	sb->s_magic = FUSE_SUPER_MAGIC;
	454	sb->s_op = &fuse_super_operations;
	455	sb->s_maxbytes = MAX_LFS_FILESIZE;
	456
	457	file = fget(d.fd);
	458	if (!file)
	459	return -EINVAL;
	460
	461	fc = get_conn(file, sb);
	462	fput(file);
334f485d MS	463	if (IS_ERR(fc))
334f485d MS	464	return PTR_ERR(fc);
d8a5ba45	465
1e9a4ed9	466	fc->flags = d.flags;
d8a5ba45	467	fc->user_id = d.user_id;
db50b96c MS	468	fc->max_read = d.max_read;
	469	if (fc->max_read / PAGE_CACHE_SIZE < fc->bdi.ra_pages)
	470	fc->bdi.ra_pages = fc->max_read / PAGE_CACHE_SIZE;
d8a5ba45	471
d8a5ba45 MS	472	err = -ENOMEM;
	473	root = get_root_inode(sb, d.rootmode);
	474	if (root == NULL)
	475	goto err;
	476
	477	sb->s_root = d_alloc_root(root);
	478	if (!sb->s_root) {
	479	iput(root);
	480	goto err;
	481	}
334f485d	482	fuse_send_init(fc);
d8a5ba45 MS	483	return 0;
	484
	485	err:
	486	spin_lock(&fuse_lock);
d8a5ba45 MS	487	fuse_release_conn(fc);
d8a5ba45 MS	488	spin_unlock(&fuse_lock);
d8a5ba45 MS	489	return err;
	490	}
	491
	492	static struct super_block fuse_get_sb(struct file_system_type fs_type,
	493	int flags, const char *dev_name,
	494	void *raw_data)
	495	{
	496	return get_sb_nodev(fs_type, flags, raw_data, fuse_fill_super);
	497	}
	498
	499	static struct file_system_type fuse_fs_type = {
	500	.owner = THIS_MODULE,
	501	.name = "fuse",
	502	.get_sb = fuse_get_sb,
	503	.kill_sb = kill_anon_super,
	504	};
	505
	506	static void fuse_inode_init_once(void foo, kmem_cache_t cachep,
	507	unsigned long flags)
	508	{
	509	struct inode * inode = foo;
	510
	511	if ((flags & (SLAB_CTOR_VERIFY\|SLAB_CTOR_CONSTRUCTOR)) ==
	512	SLAB_CTOR_CONSTRUCTOR)
	513	inode_init_once(inode);
	514	}
	515
	516	static int __init fuse_fs_init(void)
	517	{
	518	int err;
	519
	520	err = register_filesystem(&fuse_fs_type);
	521	if (err)
	522	printk("fuse: failed to register filesystem\n");
	523	else {
	524	fuse_inode_cachep = kmem_cache_create("fuse_inode",
	525	sizeof(struct fuse_inode),
	526	0, SLAB_HWCACHE_ALIGN,
	527	fuse_inode_init_once, NULL);
	528	if (!fuse_inode_cachep) {
	529	unregister_filesystem(&fuse_fs_type);
	530	err = -ENOMEM;
	531	}
	532	}
	533
	534	return err;
	535	}
	536
	537	static void fuse_fs_cleanup(void)
	538	{
	539	unregister_filesystem(&fuse_fs_type);
	540	kmem_cache_destroy(fuse_inode_cachep);
	541	}
	542
	543	static int __init fuse_init(void)
	544	{
	545	int res;
	546
	547	printk("fuse init (API version %i.%i)\n",
	548	FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);
	549
	550	spin_lock_init(&fuse_lock);
	551	res = fuse_fs_init();
	552	if (res)
553	goto err;
554
334f485d MS	555	res = fuse_dev_init();
	556	if (res)
	557	goto err_fs_cleanup;
	558
d8a5ba45 MS	559	return 0;
d8a5ba45 MS	560
334f485d MS	561	err_fs_cleanup:
334f485d MS	562	fuse_fs_cleanup();
d8a5ba45 MS	563	err:
	564	return res;
	565	}
	566
	567	static void __exit fuse_exit(void)
	568	{
	569	printk(KERN_DEBUG "fuse exit\n");
	570
	571	fuse_fs_cleanup();
334f485d	572	fuse_dev_cleanup();
d8a5ba45 MS	573	}
	574
	575	module_init(fuse_init);
	576	module_exit(fuse_exit);