[linux-block.git] / fs / 9p / v9fs.h

/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * V9FS definitions.
 *
 *  Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
 *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
 */
#ifndef FS_9P_V9FS_H
#define FS_9P_V9FS_H

#include <linux/backing-dev.h>
#include <linux/netfs.h>

/**
 * enum p9_session_flags - option flags for each 9P session
 * @V9FS_PROTO_2000U: whether or not to use 9P2000.u extensions
 * @V9FS_PROTO_2000L: whether or not to use 9P2000.l extensions
 * @V9FS_ACCESS_SINGLE: only the mounting user can access the hierarchy
 * @V9FS_ACCESS_USER: a new attach will be issued for every user (default)
 * @V9FS_ACCESS_CLIENT: Just like user, but access check is performed on client.
 * @V9FS_ACCESS_ANY: use a single attach for all users
 * @V9FS_ACCESS_MASK: bit mask of different ACCESS options
 * @V9FS_POSIX_ACL: POSIX ACLs are enforced
 *
 * Session flags reflect options selected by users at mount time
 */
#define	V9FS_ACCESS_ANY (V9FS_ACCESS_SINGLE | \
			 V9FS_ACCESS_USER |   \
			 V9FS_ACCESS_CLIENT)
#define V9FS_ACCESS_MASK V9FS_ACCESS_ANY
#define V9FS_ACL_MASK V9FS_POSIX_ACL

enum p9_session_flags {
	V9FS_PROTO_2000U	= 0x01,
	V9FS_PROTO_2000L	= 0x02,
	V9FS_ACCESS_SINGLE	= 0x04,
	V9FS_ACCESS_USER	= 0x08,
	V9FS_ACCESS_CLIENT	= 0x10,
	V9FS_POSIX_ACL		= 0x20
};

/* possible values of ->cache */
/**
 * enum p9_cache_modes - user specified cache preferences
 * @CACHE_NONE: do not cache data, dentries, or directory contents (default)
 * @CACHE_LOOSE: cache data, dentries, and directory contents w/no consistency
 *
 * eventually support loose, tight, time, session, default always none
 */

enum p9_cache_modes {
	CACHE_NONE,
	CACHE_MMAP,
	CACHE_LOOSE,
	CACHE_FSCACHE,
	nr__p9_cache_modes
};

/**
 * struct v9fs_session_info - per-instance session information
 * @flags: session options of type &p9_session_flags
 * @nodev: set to 1 to disable device mapping
 * @debug: debug level
 * @afid: authentication handle
 * @cache: cache mode of type &p9_cache_modes
 * @cachetag: the tag of the cache associated with this session
 * @fscache: session cookie associated with FS-Cache
 * @uname: string user name to mount hierarchy as
 * @aname: mount specifier for remote hierarchy
 * @maxdata: maximum data to be sent/recvd per protocol message
 * @dfltuid: default numeric userid to mount hierarchy as
 * @dfltgid: default numeric groupid to mount hierarchy as
 * @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy
 * @clnt: reference to 9P network client instantiated for this session
 * @slist: reference to list of registered 9p sessions
 *
 * This structure holds state for each session instance established during
 * a sys_mount() .
 *
 * Bugs: there seems to be a lot of state which could be condensed and/or
 * removed.
 */

struct v9fs_session_info {
	/* options */
	unsigned char flags;
	unsigned char nodev;
	unsigned short debug;
	unsigned int afid;
	unsigned int cache;
#ifdef CONFIG_9P_FSCACHE
	char *cachetag;
	struct fscache_volume *fscache;
#endif

	char *uname;		/* user name to mount as */
	char *aname;		/* name of remote hierarchy being mounted */
	unsigned int maxdata;	/* max data for client interface */
	kuid_t dfltuid;		/* default uid/muid for legacy support */
	kgid_t dfltgid;		/* default gid for legacy support */
	kuid_t uid;		/* if ACCESS_SINGLE, the uid that has access */
	struct p9_client *clnt;	/* 9p client */
	struct list_head slist; /* list of sessions registered with v9fs */
	struct rw_semaphore rename_sem;
	long session_lock_timeout; /* retry interval for blocking locks */
};

/* cache_validity flags */
#define V9FS_INO_INVALID_ATTR 0x01

struct v9fs_inode {
	struct netfs_inode netfs; /* Netfslib context and vfs inode */
	struct p9_qid qid;
	unsigned int cache_validity;
	struct p9_fid *writeback_fid;
	struct mutex v_mutex;
};

static inline struct v9fs_inode *V9FS_I(const struct inode *inode)
{
	return container_of(inode, struct v9fs_inode, netfs.inode);
}

static inline struct fscache_cookie *v9fs_inode_cookie(struct v9fs_inode *v9inode)
{
#ifdef CONFIG_9P_FSCACHE
	return netfs_i_cookie(&v9inode->netfs);
#else
	return NULL;
#endif
}

static inline struct fscache_volume *v9fs_session_cache(struct v9fs_session_info *v9ses)
{
#ifdef CONFIG_9P_FSCACHE
	return v9ses->fscache;
#else
	return NULL;
#endif
}


extern int v9fs_show_options(struct seq_file *m, struct dentry *root);

struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
				 const char *dev_name, char *data);
extern void v9fs_session_close(struct v9fs_session_info *v9ses);
extern void v9fs_session_cancel(struct v9fs_session_info *v9ses);
extern void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses);
extern struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry,
				      unsigned int flags);
extern int v9fs_vfs_unlink(struct inode *i, struct dentry *d);
extern int v9fs_vfs_rmdir(struct inode *i, struct dentry *d);
extern int v9fs_vfs_rename(struct user_namespace *mnt_userns,
			   struct inode *old_dir, struct dentry *old_dentry,
			   struct inode *new_dir, struct dentry *new_dentry,
			   unsigned int flags);
extern struct inode *v9fs_inode_from_fid(struct v9fs_session_info *v9ses,
					 struct p9_fid *fid,
					 struct super_block *sb, int new);
extern const struct inode_operations v9fs_dir_inode_operations_dotl;
extern const struct inode_operations v9fs_file_inode_operations_dotl;
extern const struct inode_operations v9fs_symlink_inode_operations_dotl;
extern const struct netfs_request_ops v9fs_req_ops;
extern struct inode *v9fs_inode_from_fid_dotl(struct v9fs_session_info *v9ses,
					      struct p9_fid *fid,
					      struct super_block *sb, int new);

/* other default globals */
#define V9FS_PORT	564
#define V9FS_DEFUSER	"nobody"
#define V9FS_DEFANAME	""
#define V9FS_DEFUID	KUIDT_INIT(-2)
#define V9FS_DEFGID	KGIDT_INIT(-2)

static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode)
{
	return inode->i_sb->s_fs_info;
}

static inline struct v9fs_session_info *v9fs_dentry2v9ses(struct dentry *dentry)
{
	return dentry->d_sb->s_fs_info;
}

static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses)
{
	return v9ses->flags & V9FS_PROTO_2000U;
}

static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses)
{
	return v9ses->flags & V9FS_PROTO_2000L;
}

/**
 * v9fs_get_inode_from_fid - Helper routine to populate an inode by
 * issuing a attribute request
 * @v9ses: session information
 * @fid: fid to issue attribute request for
 * @sb: superblock on which to create inode
 *
 */
static inline struct inode *
v9fs_get_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
			struct super_block *sb)
{
	if (v9fs_proto_dotl(v9ses))
		return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 0);
	else
		return v9fs_inode_from_fid(v9ses, fid, sb, 0);
}

/**
 * v9fs_get_new_inode_from_fid - Helper routine to populate an inode by
 * issuing a attribute request
 * @v9ses: session information
 * @fid: fid to issue attribute request for
 * @sb: superblock on which to create inode
 *
 */
static inline struct inode *
v9fs_get_new_inode_from_fid(struct v9fs_session_info *v9ses, struct p9_fid *fid,
			    struct super_block *sb)
{
	if (v9fs_proto_dotl(v9ses))
		return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 1);
	else
		return v9fs_inode_from_fid(v9ses, fid, sb, 1);
}

#endif
Commit	Line	Data
1f327613	1	/* SPDX-License-Identifier: GPL-2.0-only */
9e82cf6a EVH	2	/*
	3	* V9FS definitions.
	4	*
8a0dc95f	5	* Copyright (C) 2004-2008 by Eric Van Hensbergen <ericvh@gmail.com>
9e82cf6a	6	* Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
9e82cf6a	7	*/
e0459f57 AK	8	#ifndef FS_9P_V9FS_H
	9	#define FS_9P_V9FS_H
	10
0ed07ddb	11	#include <linux/backing-dev.h>
bc899ee1	12	#include <linux/netfs.h>
9e82cf6a	13
ee443996 EVH	14	/**
ee443996 EVH	15	* enum p9_session_flags - option flags for each 9P session
dd6102fb	16	* @V9FS_PROTO_2000U: whether or not to use 9P2000.u extensions
45bc21ed	17	* @V9FS_PROTO_2000L: whether or not to use 9P2000.l extensions
ee443996 EVH	18	* @V9FS_ACCESS_SINGLE: only the mounting user can access the hierarchy
ee443996 EVH	19	* @V9FS_ACCESS_USER: a new attach will be issued for every user (default)
e782ef71	20	* @V9FS_ACCESS_CLIENT: Just like user, but access check is performed on client.
ee443996 EVH	21	* @V9FS_ACCESS_ANY: use a single attach for all users
ee443996 EVH	22	* @V9FS_ACCESS_MASK: bit mask of different ACCESS options
e782ef71	23	* @V9FS_POSIX_ACL: POSIX ACLs are enforced
ee443996 EVH	24	*
	25	* Session flags reflect options selected by users at mount time
	26	*/
76381a42 AK	27	#define V9FS_ACCESS_ANY (V9FS_ACCESS_SINGLE \| \
	28	V9FS_ACCESS_USER \| \
	29	V9FS_ACCESS_CLIENT)
	30	#define V9FS_ACCESS_MASK V9FS_ACCESS_ANY
e782ef71	31	#define V9FS_ACL_MASK V9FS_POSIX_ACL
76381a42	32
ee443996	33	enum p9_session_flags {
dd6102fb	34	V9FS_PROTO_2000U = 0x01,
45bc21ed	35	V9FS_PROTO_2000L = 0x02,
dd6102fb SK	36	V9FS_ACCESS_SINGLE = 0x04,
dd6102fb SK	37	V9FS_ACCESS_USER = 0x08,
e782ef71 VJJ	38	V9FS_ACCESS_CLIENT = 0x10,
e782ef71 VJJ	39	V9FS_POSIX_ACL = 0x20
ee443996 EVH	40	};
	41
	42	/* possible values of ->cache */
	43	/**
	44	* enum p9_cache_modes - user specified cache preferences
	45	* @CACHE_NONE: do not cache data, dentries, or directory contents (default)
	46	* @CACHE_LOOSE: cache data, dentries, and directory contents w/no consistency
	47	*
	48	* eventually support loose, tight, time, session, default always none
	49	*/
	50
	51	enum p9_cache_modes {
	52	CACHE_NONE,
fb89b45c	53	CACHE_MMAP,
ee443996	54	CACHE_LOOSE,
60e78d2c	55	CACHE_FSCACHE,
c4fac910	56	nr__p9_cache_modes
ee443996 EVH	57	};
	58
	59	/**
	60	* struct v9fs_session_info - per-instance session information
	61	* @flags: session options of type &p9_session_flags
	62	* @nodev: set to 1 to disable device mapping
	63	* @debug: debug level
	64	* @afid: authentication handle
	65	* @cache: cache mode of type &p9_cache_modes
60e78d2c AK	66	* @cachetag: the tag of the cache associated with this session
60e78d2c AK	67	* @fscache: session cookie associated with FS-Cache
ee443996 EVH	68	* @uname: string user name to mount hierarchy as
	69	* @aname: mount specifier for remote hierarchy
	70	* @maxdata: maximum data to be sent/recvd per protocol message
	71	* @dfltuid: default numeric userid to mount hierarchy as
	72	* @dfltgid: default numeric groupid to mount hierarchy as
	73	* @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy
	74	* @clnt: reference to 9P network client instantiated for this session
60e78d2c	75	* @slist: reference to list of registered 9p sessions
ee443996 EVH	76	*
	77	* This structure holds state for each session instance established during
	78	* a sys_mount() .
	79	*
	80	* Bugs: there seems to be a lot of state which could be condensed and/or
	81	* removed.
	82	*/
9e82cf6a EVH	83
	84	struct v9fs_session_info {
	85	/* options */
ee443996 EVH	86	unsigned char flags;
	87	unsigned char nodev;
	88	unsigned short debug;
	89	unsigned int afid;
	90	unsigned int cache;
60e78d2c AK	91	#ifdef CONFIG_9P_FSCACHE
60e78d2c AK	92	char *cachetag;
24e42e32	93	struct fscache_volume *fscache;
60e78d2c	94	#endif
9e82cf6a	95
ba17674f LI	96	char uname; / user name to mount as */
ba17674f LI	97	char aname; / name of remote hierarchy being mounted */
8a0dc95f	98	unsigned int maxdata; /* max data for client interface */
76ed23a5 EB	99	kuid_t dfltuid; /* default uid/muid for legacy support */
	100	kgid_t dfltgid; /* default gid for legacy support */
	101	kuid_t uid; /* if ACCESS_SINGLE, the uid that has access */
bd238fb4	102	struct p9_client clnt; / 9p client */
60e78d2c	103	struct list_head slist; /* list of sessions registered with v9fs */
a534c8d1	104	struct rw_semaphore rename_sem;
5e172f75	105	long session_lock_timeout; /* retry interval for blocking locks */
9e82cf6a EVH	106	};
9e82cf6a EVH	107
b3cbea03 AK	108	/* cache_validity flags */
	109	#define V9FS_INO_INVALID_ATTR 0x01
	110
a78ce05d	111	struct v9fs_inode {
874c8ca1	112	struct netfs_inode netfs; /* Netfslib context and vfs inode */
fd2421f5	113	struct p9_qid qid;
b3cbea03	114	unsigned int cache_validity;
6b39f6d2	115	struct p9_fid *writeback_fid;
5a7e0a8c	116	struct mutex v_mutex;
a78ce05d AK	117	};
	118
	119	static inline struct v9fs_inode V9FS_I(const struct inode inode)
	120	{
874c8ca1	121	return container_of(inode, struct v9fs_inode, netfs.inode);
a78ce05d AK	122	}
a78ce05d AK	123
eb497943 DH	124	static inline struct fscache_cookie v9fs_inode_cookie(struct v9fs_inode v9inode)
	125	{
	126	#ifdef CONFIG_9P_FSCACHE
e81fb419	127	return netfs_i_cookie(&v9inode->netfs);
eb497943 DH	128	#else
	129	return NULL;
	130	#endif
	131	}
	132
24e42e32 DH	133	static inline struct fscache_volume v9fs_session_cache(struct v9fs_session_info v9ses)
	134	{
	135	#ifdef CONFIG_9P_FSCACHE
	136	return v9ses->fscache;
	137	#else
	138	return NULL;
	139	#endif
	140	}
	141
	142
c4fac910 DH	143	extern int v9fs_show_options(struct seq_file m, struct dentry root);
c4fac910 DH	144
772712c5 SM	145	struct p9_fid v9fs_session_init(struct v9fs_session_info v9ses,
772712c5 SM	146	const char dev_name, char data);
53c06f4e AK	147	extern void v9fs_session_close(struct v9fs_session_info *v9ses);
	148	extern void v9fs_session_cancel(struct v9fs_session_info *v9ses);
	149	extern void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses);
	150	extern struct dentry v9fs_vfs_lookup(struct inode dir, struct dentry *dentry,
772712c5	151	unsigned int flags);
53c06f4e AK	152	extern int v9fs_vfs_unlink(struct inode i, struct dentry d);
53c06f4e AK	153	extern int v9fs_vfs_rmdir(struct inode i, struct dentry d);
549c7297 CB	154	extern int v9fs_vfs_rename(struct user_namespace *mnt_userns,
549c7297 CB	155	struct inode old_dir, struct dentry old_dentry,
1cd66c93 MS	156	struct inode new_dir, struct dentry new_dentry,
1cd66c93 MS	157	unsigned int flags);
a78ce05d AK	158	extern struct inode v9fs_inode_from_fid(struct v9fs_session_info v9ses,
a78ce05d AK	159	struct p9_fid *fid,
ed80fcfa	160	struct super_block *sb, int new);
53c06f4e AK	161	extern const struct inode_operations v9fs_dir_inode_operations_dotl;
	162	extern const struct inode_operations v9fs_file_inode_operations_dotl;
	163	extern const struct inode_operations v9fs_symlink_inode_operations_dotl;
bc899ee1	164	extern const struct netfs_request_ops v9fs_req_ops;
a78ce05d AK	165	extern struct inode v9fs_inode_from_fid_dotl(struct v9fs_session_info v9ses,
a78ce05d AK	166	struct p9_fid *fid,
ed80fcfa	167	struct super_block *sb, int new);
9e82cf6a	168
9e82cf6a	169	/* other default globals */
bd32b82d	170	#define V9FS_PORT 564
9e82cf6a EVH	171	#define V9FS_DEFUSER "nobody"
9e82cf6a EVH	172	#define V9FS_DEFANAME ""
76ed23a5 EB	173	#define V9FS_DEFUID KUIDT_INIT(-2)
76ed23a5 EB	174	#define V9FS_DEFGID KGIDT_INIT(-2)
9e82cf6a	175
bd238fb4 LI	176	static inline struct v9fs_session_info v9fs_inode2v9ses(struct inode inode)
bd238fb4 LI	177	{
772712c5	178	return inode->i_sb->s_fs_info;
bd238fb4	179	}
2405669b	180
42869c8a AK	181	static inline struct v9fs_session_info v9fs_dentry2v9ses(struct dentry dentry)
	182	{
	183	return dentry->d_sb->s_fs_info;
	184	}
	185
dd6102fb	186	static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses)
2405669b	187	{
dd6102fb SK	188	return v9ses->flags & V9FS_PROTO_2000U;
	189	}
	190
	191	static inline int v9fs_proto_dotl(struct v9fs_session_info *v9ses)
	192	{
45bc21ed	193	return v9ses->flags & V9FS_PROTO_2000L;
2405669b	194	}
53c06f4e AK	195
53c06f4e AK	196	/**
a78ce05d	197	* v9fs_get_inode_from_fid - Helper routine to populate an inode by
53c06f4e AK	198	* issuing a attribute request
	199	* @v9ses: session information
	200	* @fid: fid to issue attribute request for
	201	* @sb: superblock on which to create inode
	202	*
	203	*/
	204	static inline struct inode *
a78ce05d AK	205	v9fs_get_inode_from_fid(struct v9fs_session_info v9ses, struct p9_fid fid,
a78ce05d AK	206	struct super_block *sb)
53c06f4e AK	207	{
53c06f4e AK	208	if (v9fs_proto_dotl(v9ses))
ed80fcfa	209	return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 0);
53c06f4e	210	else
ed80fcfa	211	return v9fs_inode_from_fid(v9ses, fid, sb, 0);
53c06f4e	212	}
ed80fcfa AK	213
	214	/**
	215	* v9fs_get_new_inode_from_fid - Helper routine to populate an inode by
	216	* issuing a attribute request
	217	* @v9ses: session information
	218	* @fid: fid to issue attribute request for
	219	* @sb: superblock on which to create inode
	220	*
	221	*/
	222	static inline struct inode *
	223	v9fs_get_new_inode_from_fid(struct v9fs_session_info v9ses, struct p9_fid fid,
	224	struct super_block *sb)
	225	{
	226	if (v9fs_proto_dotl(v9ses))
	227	return v9fs_inode_from_fid_dotl(v9ses, fid, sb, 1);
	228	else
	229	return v9fs_inode_from_fid(v9ses, fid, sb, 1);
	230	}
	231
e0459f57	232	#endif