1 /* 2 * include/net/9p/client.h 3 * 4 * 9P Client Definitions 5 * 6 * Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com> 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 29 #include <linux/utsname.h> 30 31 /* Number of requests per row */ 32 #define P9_ROW_MAXTAG 255 33 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 37 * @p9_proto_2000L: 9P2000.L extension 38 */ 39 40 enum p9_proto_versions{ 41 p9_proto_legacy, 42 p9_proto_2000u, 43 p9_proto_2000L, 44 }; 45 46 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, 59 BeginDisconnect, 60 Disconnected, 61 Hung, 62 }; 63 64 /** 65 * enum p9_req_status_t - status of a request 66 * @REQ_STATUS_IDLE: request slot unused 67 * @REQ_STATUS_ALLOC: request has been allocated but not sent 68 * @REQ_STATUS_UNSENT: request waiting to be sent 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 73 * @REQ_STATUS_ERROR: request encountered an error on the client side 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, 84 REQ_STATUS_UNSENT, 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 96 * @flush_tag: tag of request being flushed (for flush requests) 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) 101 * @req_list: link for higher level objects to chain requests 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 106 * tag id is a index into an array. (We use tag+1 so that we can accommodate 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; 120 void *aux; 121 122 struct list_head req_list; 123 }; 124 125 /** 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 130 * @proto_version: 9P protocol version to use 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 136 * @tagpool - transaction id accounting for session 137 * @reqs - 2D array of requests 138 * @max_tag - current maximum tag id allocated 139 * @name - node name used as client id 140 * 141 * The client structure is used to keep track of various per-client 142 * state that has been instantiated. 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. 151 * 152 * Bugs: duplicated data and potentially unnecessary elements. 153 */ 154 155 struct p9_client { 156 spinlock_t lock; /* protect client structure */ 157 unsigned int msize; 158 unsigned char proto_version; 159 struct p9_trans_module *trans_mod; 160 enum p9_trans_status status; 161 void *trans; 162 struct p9_conn *conn; 163 164 struct p9_idpool *fidpool; 165 struct list_head fidlist; 166 167 struct p9_idpool *tagpool; 168 struct p9_req_t *reqs[P9_ROW_MAXTAG]; 169 int max_tag; 170 171 char name[__NEW_UTS_LEN + 1]; 172 }; 173 174 /** 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 182 * @rdir: readdir accounting structure (allocated on demand) 183 * @flist: per-client-instance fid tracking 184 * @dlist: per-dentry fid tracking 185 * 186 * TODO: This needs lots of explanation. 187 */ 188 189 struct p9_fid { 190 struct p9_client *clnt; 191 u32 fid; 192 int mode; 193 struct p9_qid qid; 194 u32 iounit; 195 kuid_t uid; 196 197 void *rdir; 198 199 struct list_head flist; 200 struct hlist_node dlist; /* list of all fids attached to a dentry */ 201 }; 202 203 /** 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 }; 217 218 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb); 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); 223 struct p9_client *p9_client_create(const char *dev_name, char *options); 224 void p9_client_destroy(struct p9_client *clnt); 225 void p9_client_disconnect(struct p9_client *clnt); 226 void p9_client_begin_disconnect(struct p9_client *clnt); 227 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid, 228 char *uname, kuid_t n_uname, char *aname); 229 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname, 230 char **wnames, int clone); 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); 234 int p9_client_link(struct p9_fid *fid, struct p9_fid *oldfid, char *newname); 235 int p9_client_symlink(struct p9_fid *fid, char *name, char *symname, kgid_t gid, 236 struct p9_qid *qid); 237 int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode, 238 kgid_t gid, struct p9_qid *qid); 239 int p9_client_clunk(struct p9_fid *fid); 240 int p9_client_fsync(struct p9_fid *fid, int datasync); 241 int p9_client_remove(struct p9_fid *fid); 242 int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags); 243 int p9_client_read(struct p9_fid *fid, char *data, char __user *udata, 244 u64 offset, u32 count); 245 int p9_client_write(struct p9_fid *fid, char *data, const char __user *udata, 246 u64 offset, u32 count); 247 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset); 248 int p9dirent_read(struct p9_client *clnt, char *buf, int len, 249 struct p9_dirent *dirent); 250 struct p9_wstat *p9_client_stat(struct p9_fid *fid); 251 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst); 252 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *attr); 253 254 struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid, 255 u64 request_mask); 256 257 int p9_client_mknod_dotl(struct p9_fid *oldfid, char *name, int mode, 258 dev_t rdev, kgid_t gid, struct p9_qid *); 259 int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode, 260 kgid_t gid, struct p9_qid *); 261 int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status); 262 int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *fl); 263 struct p9_req_t *p9_tag_lookup(struct p9_client *, u16); 264 void p9_client_cb(struct p9_client *c, struct p9_req_t *req); 265 266 int p9_parse_header(struct p9_fcall *, int32_t *, int8_t *, int16_t *, int); 267 int p9stat_read(struct p9_client *, char *, int, struct p9_wstat *); 268 void p9stat_free(struct p9_wstat *); 269 270 int p9_is_proto_dotu(struct p9_client *clnt); 271 int p9_is_proto_dotl(struct p9_client *clnt); 272 struct p9_fid *p9_client_xattrwalk(struct p9_fid *, const char *, u64 *); 273 int p9_client_xattrcreate(struct p9_fid *, const char *, u64, int); 274 int p9_client_readlink(struct p9_fid *fid, char **target); 275 276 #endif /* NET_9P_CLIENT_H */ 277