[mirror_ubuntu-zesty-kernel.git] / include / net / 9p / client.h

/*
 * include/net/9p/client.h
 *
 * 9P Client Definitions
 *
 *  Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
 *  Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2
 *  as published by the Free Software Foundation.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to:
 *  Free Software Foundation
 *  51 Franklin Street, Fifth Floor
 *  Boston, MA  02111-1301  USA
 *
 */

#ifndef NET_9P_CLIENT_H
#define NET_9P_CLIENT_H

#include <linux/utsname.h>

/* Number of requests per row */
#define P9_ROW_MAXTAG 255

/** enum p9_proto_versions - 9P protocol versions
 * @p9_proto_legacy: 9P Legacy mode, pre-9P2000.u
 * @p9_proto_2000u: 9P2000.u extension
 * @p9_proto_2000L: 9P2000.L extension
 */

enum p9_proto_versions{
	p9_proto_legacy,
	p9_proto_2000u,
	p9_proto_2000L,
};


/**
 * enum p9_trans_status - different states of underlying transports
 * @Connected: transport is connected and healthy
 * @Disconnected: transport has been disconnected
 * @Hung: transport is connected by wedged
 *
 * This enumeration details the various states a transport
 * instatiation can be in.
 */

enum p9_trans_status {
	Connected,
	BeginDisconnect,
	Disconnected,
	Hung,
};

/**
 * enum p9_req_status_t - status of a request
 * @REQ_STATUS_IDLE: request slot unused
 * @REQ_STATUS_ALLOC: request has been allocated but not sent
 * @REQ_STATUS_UNSENT: request waiting to be sent
 * @REQ_STATUS_SENT: request sent to server
 * @REQ_STATUS_FLSH: a flush has been sent for this request
 * @REQ_STATUS_RCVD: response received from server
 * @REQ_STATUS_FLSHD: request has been flushed
 * @REQ_STATUS_ERROR: request encountered an error on the client side
 *
 * The @REQ_STATUS_IDLE state is used to mark a request slot as unused
 * but use is actually tracked by the idpool structure which handles tag
 * id allocation.
 *
 */

enum p9_req_status_t {
	REQ_STATUS_IDLE,
	REQ_STATUS_ALLOC,
	REQ_STATUS_UNSENT,
	REQ_STATUS_SENT,
	REQ_STATUS_FLSH,
	REQ_STATUS_RCVD,
	REQ_STATUS_FLSHD,
	REQ_STATUS_ERROR,
};

/**
 * struct p9_req_t - request slots
 * @status: status of this request slot
 * @t_err: transport error
 * @flush_tag: tag of request being flushed (for flush requests)
 * @wq: wait_queue for the client to block on for this request
 * @tc: the request fcall structure
 * @rc: the response fcall structure
 * @aux: transport specific data (provided for trans_fd migration)
 * @req_list: link for higher level objects to chain requests
 *
 * Transport use an array to track outstanding requests
 * instead of a list.  While this may incurr overhead during initial
 * allocation or expansion, it makes request lookup much easier as the
 * tag id is a index into an array.  (We use tag+1 so that we can accommodate
 * the -1 tag for the T_VERSION request).
 * This also has the nice effect of only having to allocate wait_queues
 * once, instead of constantly allocating and freeing them.  Its possible
 * other resources could benefit from this scheme as well.
 *
 */

struct p9_req_t {
	int status;
	int t_err;
	wait_queue_head_t *wq;
	struct p9_fcall *tc;
	struct p9_fcall *rc;
	void *aux;

	struct list_head req_list;
};

/**
 * struct p9_client - per client instance state
 * @lock: protect @fidlist
 * @msize: maximum data size negotiated by protocol
 * @dotu: extension flags negotiated by protocol
 * @proto_version: 9P protocol version to use
 * @trans_mod: module API instantiated with this client
 * @trans: tranport instance state and API
 * @conn: connection state information used by trans_fd
 * @fidpool: fid handle accounting for session
 * @fidlist: List of active fid handles
 * @tagpool - transaction id accounting for session
 * @reqs - 2D array of requests
 * @max_tag - current maximum tag id allocated
 * @name - node name used as client id
 *
 * The client structure is used to keep track of various per-client
 * state that has been instantiated.
 * In order to minimize per-transaction overhead we use a
 * simple array to lookup requests instead of a hash table
 * or linked list.  In order to support larger number of
 * transactions, we make this a 2D array, allocating new rows
 * when we need to grow the total number of the transactions.
 *
 * Each row is 256 requests and we'll support up to 256 rows for
 * a total of 64k concurrent requests per session.
 *
 * Bugs: duplicated data and potentially unnecessary elements.
 */

struct p9_client {
	spinlock_t lock; /* protect client structure */
	unsigned int msize;
	unsigned char proto_version;
	struct p9_trans_module *trans_mod;
	enum p9_trans_status status;
	void *trans;
	struct p9_conn *conn;

	struct p9_idpool *fidpool;
	struct list_head fidlist;

	struct p9_idpool *tagpool;
	struct p9_req_t *reqs[P9_ROW_MAXTAG];
	int max_tag;

	char name[__NEW_UTS_LEN + 1];
};

/**
 * struct p9_fid - file system entity handle
 * @clnt: back pointer to instantiating &p9_client
 * @fid: numeric identifier for this handle
 * @mode: current mode of this fid (enum?)
 * @qid: the &p9_qid server identifier this handle points to
 * @iounit: the server reported maximum transaction size for this file
 * @uid: the numeric uid of the local user who owns this handle
 * @rdir: readdir accounting structure (allocated on demand)
 * @flist: per-client-instance fid tracking
 * @dlist: per-dentry fid tracking
 *
 * TODO: This needs lots of explanation.
 */

struct p9_fid {
	struct p9_client *clnt;
	u32 fid;
	int mode;
	struct p9_qid qid;
	u32 iounit;
	kuid_t uid;

	void *rdir;

	struct list_head flist;
	struct hlist_node dlist;	/* list of all fids attached to a dentry */
};

/**
 * struct p9_dirent - directory entry structure
 * @qid: The p9 server qid for this dirent
 * @d_off: offset to the next dirent
 * @d_type: type of file
 * @d_name: file name
 */

struct p9_dirent {
	struct p9_qid qid;
	u64 d_off;
	unsigned char d_type;
	char d_name[256];
};

int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb);
int p9_client_rename(struct p9_fid *fid, struct p9_fid *newdirfid,
		     const char *name);
int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name,
		       struct p9_fid *newdirfid, const char *new_name);
struct p9_client *p9_client_create(const char *dev_name, char *options);
void p9_client_destroy(struct p9_client *clnt);
void p9_client_disconnect(struct p9_client *clnt);
void p9_client_begin_disconnect(struct p9_client *clnt);
struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid,
				char *uname, kuid_t n_uname, char *aname);
struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname,
		char **wnames, int clone);
int p9_client_open(struct p9_fid *fid, int mode);
int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode,
							char *extension);
int p9_client_link(struct p9_fid *fid, struct p9_fid *oldfid, char *newname);
int p9_client_symlink(struct p9_fid *fid, char *name, char *symname, kgid_t gid,
							struct p9_qid *qid);
int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode,
		kgid_t gid, struct p9_qid *qid);
int p9_client_clunk(struct p9_fid *fid);
int p9_client_fsync(struct p9_fid *fid, int datasync);
int p9_client_remove(struct p9_fid *fid);
int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags);
int p9_client_read(struct p9_fid *fid, char *data, char __user *udata,
							u64 offset, u32 count);
int p9_client_write(struct p9_fid *fid, char *data, const char __user *udata,
							u64 offset, u32 count);
int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset);
int p9dirent_read(struct p9_client *clnt, char *buf, int len,
		  struct p9_dirent *dirent);
struct p9_wstat *p9_client_stat(struct p9_fid *fid);
int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst);
int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *attr);

struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid,
							u64 request_mask);

int p9_client_mknod_dotl(struct p9_fid *oldfid, char *name, int mode,
			dev_t rdev, kgid_t gid, struct p9_qid *);
int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode,
				kgid_t gid, struct p9_qid *);
int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status);
int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *fl);
struct p9_req_t *p9_tag_lookup(struct p9_client *, u16);
void p9_client_cb(struct p9_client *c, struct p9_req_t *req);

int p9_parse_header(struct p9_fcall *, int32_t *, int8_t *, int16_t *, int);
int p9stat_read(struct p9_client *, char *, int, struct p9_wstat *);
void p9stat_free(struct p9_wstat *);

int p9_is_proto_dotu(struct p9_client *clnt);
int p9_is_proto_dotl(struct p9_client *clnt);
struct p9_fid *p9_client_xattrwalk(struct p9_fid *, const char *, u64 *);
int p9_client_xattrcreate(struct p9_fid *, const char *, u64, int);
int p9_client_readlink(struct p9_fid *fid, char **target);

#endif /* NET_9P_CLIENT_H */
Commit	Line	Data
bd238fb4 LI	1	/*
	2	* include/net/9p/client.h
	3	*
	4	* 9P Client Definitions
	5	*
8a0dc95f	6	* Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
bd238fb4 LI	7	* Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net>
	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License version 2
	11	* as published by the Free Software Foundation.
	12	*
	13	* This program is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	* GNU General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License
	19	* along with this program; if not, write to:
	20	* Free Software Foundation
	21	* 51 Franklin Street, Fifth Floor
	22	* Boston, MA 02111-1301 USA
	23	*
	24	*/
	25
	26	#ifndef NET_9P_CLIENT_H
	27	#define NET_9P_CLIENT_H
	28
50192abe WD	29	#include <linux/utsname.h>
50192abe WD	30
fea511a6 EVH	31	/* Number of requests per row */
	32	#define P9_ROW_MAXTAG 255
	33
0fb80abd SK	34	/** enum p9_proto_versions - 9P protocol versions
	35	* @p9_proto_legacy: 9P Legacy mode, pre-9P2000.u
	36	* @p9_proto_2000u: 9P2000.u extension
45bc21ed	37	* @p9_proto_2000L: 9P2000.L extension
0fb80abd SK	38	*/
	39
	40	enum p9_proto_versions{
4d63055f PK	41	p9_proto_legacy,
	42	p9_proto_2000u,
	43	p9_proto_2000L,
0fb80abd SK	44	};
	45
	46
8b81ef58 EVH	47	/**
	48	* enum p9_trans_status - different states of underlying transports
	49	* @Connected: transport is connected and healthy
	50	* @Disconnected: transport has been disconnected
	51	* @Hung: transport is connected by wedged
	52	*
	53	* This enumeration details the various states a transport
	54	* instatiation can be in.
	55	*/
	56
	57	enum p9_trans_status {
	58	Connected,
6d96d3ab	59	BeginDisconnect,
8b81ef58 EVH	60	Disconnected,
	61	Hung,
	62	};
	63
fea511a6	64	/**
aca00763	65	* enum p9_req_status_t - status of a request
fea511a6 EVH	66	* @REQ_STATUS_IDLE: request slot unused
fea511a6 EVH	67	* @REQ_STATUS_ALLOC: request has been allocated but not sent
673d62cd	68	* @REQ_STATUS_UNSENT: request waiting to be sent
fea511a6 EVH	69	* @REQ_STATUS_SENT: request sent to server
	70	* @REQ_STATUS_FLSH: a flush has been sent for this request
	71	* @REQ_STATUS_RCVD: response received from server
	72	* @REQ_STATUS_FLSHD: request has been flushed
673d62cd	73	* @REQ_STATUS_ERROR: request encountered an error on the client side
fea511a6 EVH	74	*
	75	* The @REQ_STATUS_IDLE state is used to mark a request slot as unused
	76	* but use is actually tracked by the idpool structure which handles tag
	77	* id allocation.
	78	*
	79	*/
	80
	81	enum p9_req_status_t {
	82	REQ_STATUS_IDLE,
	83	REQ_STATUS_ALLOC,
673d62cd	84	REQ_STATUS_UNSENT,
fea511a6 EVH	85	REQ_STATUS_SENT,
	86	REQ_STATUS_FLSH,
	87	REQ_STATUS_RCVD,
	88	REQ_STATUS_FLSHD,
	89	REQ_STATUS_ERROR,
	90	};
	91
	92	/**
	93	* struct p9_req_t - request slots
	94	* @status: status of this request slot
	95	* @t_err: transport error
51a87c55	96	* @flush_tag: tag of request being flushed (for flush requests)
fea511a6 EVH	97	* @wq: wait_queue for the client to block on for this request
	98	* @tc: the request fcall structure
	99	* @rc: the response fcall structure
	100	* @aux: transport specific data (provided for trans_fd migration)
673d62cd	101	* @req_list: link for higher level objects to chain requests
fea511a6 EVH	102	*
	103	* Transport use an array to track outstanding requests
	104	* instead of a list. While this may incurr overhead during initial
	105	* allocation or expansion, it makes request lookup much easier as the
25985edc	106	* tag id is a index into an array. (We use tag+1 so that we can accommodate
fea511a6 EVH	107	* the -1 tag for the T_VERSION request).
	108	* This also has the nice effect of only having to allocate wait_queues
	109	* once, instead of constantly allocating and freeing them. Its possible
	110	* other resources could benefit from this scheme as well.
	111	*
	112	*/
	113
	114	struct p9_req_t {
	115	int status;
	116	int t_err;
	117	wait_queue_head_t *wq;
	118	struct p9_fcall *tc;
	119	struct p9_fcall *rc;
fea511a6	120	void *aux;
673d62cd	121
673d62cd	122	struct list_head req_list;
fea511a6 EVH	123	};
fea511a6 EVH	124
ee443996 EVH	125	/**
	126	* struct p9_client - per client instance state
	127	* @lock: protect @fidlist
	128	* @msize: maximum data size negotiated by protocol
	129	* @dotu: extension flags negotiated by protocol
0fb80abd	130	* @proto_version: 9P protocol version to use
ee443996 EVH	131	* @trans_mod: module API instantiated with this client
	132	* @trans: tranport instance state and API
	133	* @conn: connection state information used by trans_fd
	134	* @fidpool: fid handle accounting for session
	135	* @fidlist: List of active fid handles
fea511a6 EVH	136	* @tagpool - transaction id accounting for session
	137	* @reqs - 2D array of requests
	138	* @max_tag - current maximum tag id allocated
50192abe	139	* @name - node name used as client id
ee443996 EVH	140	*
	141	* The client structure is used to keep track of various per-client
	142	* state that has been instantiated.
fea511a6 EVH	143	* In order to minimize per-transaction overhead we use a
	144	* simple array to lookup requests instead of a hash table
	145	* or linked list. In order to support larger number of
	146	* transactions, we make this a 2D array, allocating new rows
	147	* when we need to grow the total number of the transactions.
	148	*
	149	* Each row is 256 requests and we'll support up to 256 rows for
	150	* a total of 64k concurrent requests per session.
ee443996 EVH	151	*
	152	* Bugs: duplicated data and potentially unnecessary elements.
	153	*/
	154
bd238fb4 LI	155	struct p9_client {
bd238fb4 LI	156	spinlock_t lock; /* protect client structure */
ef6b0807	157	unsigned int msize;
0fb80abd	158	unsigned char proto_version;
8a0dc95f	159	struct p9_trans_module *trans_mod;
8b81ef58 EVH	160	enum p9_trans_status status;
8b81ef58 EVH	161	void *trans;
bd238fb4 LI	162	struct p9_conn *conn;
	163
	164	struct p9_idpool *fidpool;
	165	struct list_head fidlist;
fea511a6 EVH	166
	167	struct p9_idpool *tagpool;
	168	struct p9_req_t *reqs[P9_ROW_MAXTAG];
	169	int max_tag;
50192abe WD	170
50192abe WD	171	char name[__NEW_UTS_LEN + 1];
bd238fb4 LI	172	};
bd238fb4 LI	173
ee443996 EVH	174	/**
	175	* struct p9_fid - file system entity handle
	176	* @clnt: back pointer to instantiating &p9_client
	177	* @fid: numeric identifier for this handle
	178	* @mode: current mode of this fid (enum?)
	179	* @qid: the &p9_qid server identifier this handle points to
	180	* @iounit: the server reported maximum transaction size for this file
	181	* @uid: the numeric uid of the local user who owns this handle
3e2796a9	182	* @rdir: readdir accounting structure (allocated on demand)
ee443996 EVH	183	* @flist: per-client-instance fid tracking
	184	* @dlist: per-dentry fid tracking
	185	*
	186	* TODO: This needs lots of explanation.
	187	*/
	188
bd238fb4 LI	189	struct p9_fid {
	190	struct p9_client *clnt;
	191	u32 fid;
	192	int mode;
	193	struct p9_qid qid;
	194	u32 iounit;
b4642556	195	kuid_t uid;
bd238fb4	196
3e2796a9 EVH	197	void *rdir;
3e2796a9 EVH	198
bd238fb4	199	struct list_head flist;
c4d30967	200	struct hlist_node dlist; /* list of all fids attached to a dentry */
bd238fb4 LI	201	};
bd238fb4 LI	202
7751bdb3 SK	203	/**
	204	* struct p9_dirent - directory entry structure
	205	* @qid: The p9 server qid for this dirent
	206	* @d_off: offset to the next dirent
	207	* @d_type: type of file
	208	* @d_name: file name
	209	*/
	210
	211	struct p9_dirent {
	212	struct p9_qid qid;
	213	u64 d_off;
	214	unsigned char d_type;
	215	char d_name[256];
	216	};
	217
bda8e775	218	int p9_client_statfs(struct p9_fid fid, struct p9_rstatfs sb);
9e8fb38e AK	219	int p9_client_rename(struct p9_fid fid, struct p9_fid newdirfid,
	220	const char *name);
	221	int p9_client_renameat(struct p9_fid olddirfid, const char old_name,
	222	struct p9_fid newdirfid, const char new_name);
8a0dc95f	223	struct p9_client p9_client_create(const char dev_name, char *options);
bd238fb4 LI	224	void p9_client_destroy(struct p9_client *clnt);
bd238fb4 LI	225	void p9_client_disconnect(struct p9_client *clnt);
6d96d3ab	226	void p9_client_begin_disconnect(struct p9_client *clnt);
bd238fb4	227	struct p9_fid p9_client_attach(struct p9_client clnt, struct p9_fid *afid,
f791f7c5	228	char uname, kuid_t n_uname, char aname);
b76225e2 HPB	229	struct p9_fid p9_client_walk(struct p9_fid oldfid, uint16_t nwname,
b76225e2 HPB	230	char **wnames, int clone);
bd238fb4 LI	231	int p9_client_open(struct p9_fid *fid, int mode);
	232	int p9_client_fcreate(struct p9_fid fid, char name, u32 perm, int mode,
	233	char *extension);
652df9a7	234	int p9_client_link(struct p9_fid fid, struct p9_fid oldfid, char *newname);
f791f7c5	235	int p9_client_symlink(struct p9_fid fid, char name, char *symname, kgid_t gid,
50cc42ff	236	struct p9_qid *qid);
5643135a	237	int p9_client_create_dotl(struct p9_fid ofid, char name, u32 flags, u32 mode,
f791f7c5	238	kgid_t gid, struct p9_qid *qid);
bd238fb4	239	int p9_client_clunk(struct p9_fid *fid);
b165d601	240	int p9_client_fsync(struct p9_fid *fid, int datasync);
bd238fb4	241	int p9_client_remove(struct p9_fid *fid);
48e370ff	242	int p9_client_unlinkat(struct p9_fid dfid, const char name, int flags);
0fc9655e EVH	243	int p9_client_read(struct p9_fid fid, char data, char __user *udata,
0fc9655e EVH	244	u64 offset, u32 count);
0fc9655e EVH	245	int p9_client_write(struct p9_fid fid, char data, const char __user *udata,
0fc9655e EVH	246	u64 offset, u32 count);
7751bdb3	247	int p9_client_readdir(struct p9_fid fid, char data, u32 count, u64 offset);
348b5901 AK	248	int p9dirent_read(struct p9_client clnt, char buf, int len,
348b5901 AK	249	struct p9_dirent *dirent);
51a87c55	250	struct p9_wstat p9_client_stat(struct p9_fid fid);
bd238fb4	251	int p9_client_wstat(struct p9_fid fid, struct p9_wstat wst);
87d7845a	252	int p9_client_setattr(struct p9_fid fid, struct p9_iattr_dotl attr);
bd238fb4	253
f0853122 SK	254	struct p9_stat_dotl p9_client_getattr_dotl(struct p9_fid fid,
	255	u64 request_mask);
	256
4b43516a	257	int p9_client_mknod_dotl(struct p9_fid oldfid, char name, int mode,
f791f7c5	258	dev_t rdev, kgid_t gid, struct p9_qid *);
01a622bd	259	int p9_client_mkdir_dotl(struct p9_fid fid, char name, int mode,
f791f7c5	260	kgid_t gid, struct p9_qid *);
a099027c	261	int p9_client_lock_dotl(struct p9_fid fid, struct p9_flock flock, u8 *status);
1d769cd1	262	int p9_client_getlock_dotl(struct p9_fid fid, struct p9_getlock fl);
fea511a6	263	struct p9_req_t p9_tag_lookup(struct p9_client , u16);
91b8534f	264	void p9_client_cb(struct p9_client c, struct p9_req_t req);
fea511a6	265
fc79d4b1	266	int p9_parse_header(struct p9_fcall , int32_t , int8_t , int16_t , int);
348b5901	267	int p9stat_read(struct p9_client , char , int, struct p9_wstat *);
51a87c55 EVH	268	void p9stat_free(struct p9_wstat *);
51a87c55 EVH	269
342fee1d SK	270	int p9_is_proto_dotu(struct p9_client *clnt);
342fee1d SK	271	int p9_is_proto_dotl(struct p9_client *clnt);
0ef63f34	272	struct p9_fid p9_client_xattrwalk(struct p9_fid , const char , u64 );
eda25e46	273	int p9_client_xattrcreate(struct p9_fid , const char , u64, int);
329176cc	274	int p9_client_readlink(struct p9_fid fid, char *target);
02da398b	275
bd238fb4	276	#endif /* NET_9P_CLIENT_H */