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 /* Number of requests per row */ 30 #define P9_ROW_MAXTAG 255 31 32 /** enum p9_proto_versions - 9P protocol versions 33 * @p9_proto_legacy: 9P Legacy mode, pre-9P2000.u 34 * @p9_proto_2000u: 9P2000.u extension 35 * @p9_proto_2000L: 9P2000.L extension 36 */ 37 38 enum p9_proto_versions{ 39 p9_proto_legacy, 40 p9_proto_2000u, 41 p9_proto_2000L, 42 }; 43 44 45 /** 46 * enum p9_trans_status - different states of underlying transports 47 * @Connected: transport is connected and healthy 48 * @Disconnected: transport has been disconnected 49 * @Hung: transport is connected by wedged 50 * 51 * This enumeration details the various states a transport 52 * instatiation can be in. 53 */ 54 55 enum p9_trans_status { 56 Connected, 57 BeginDisconnect, 58 Disconnected, 59 Hung, 60 }; 61 62 /** 63 * enum p9_req_status_t - status of a request 64 * @REQ_STATUS_IDLE: request slot unused 65 * @REQ_STATUS_ALLOC: request has been allocated but not sent 66 * @REQ_STATUS_UNSENT: request waiting to be sent 67 * @REQ_STATUS_SENT: request sent to server 68 * @REQ_STATUS_FLSH: a flush has been sent for this request 69 * @REQ_STATUS_RCVD: response received from server 70 * @REQ_STATUS_FLSHD: request has been flushed 71 * @REQ_STATUS_ERROR: request encountered an error on the client side 72 * 73 * The @REQ_STATUS_IDLE state is used to mark a request slot as unused 74 * but use is actually tracked by the idpool structure which handles tag 75 * id allocation. 76 * 77 */ 78 79 enum p9_req_status_t { 80 REQ_STATUS_IDLE, 81 REQ_STATUS_ALLOC, 82 REQ_STATUS_UNSENT, 83 REQ_STATUS_SENT, 84 REQ_STATUS_FLSH, 85 REQ_STATUS_RCVD, 86 REQ_STATUS_FLSHD, 87 REQ_STATUS_ERROR, 88 }; 89 90 /** 91 * struct p9_req_t - request slots 92 * @status: status of this request slot 93 * @t_err: transport error 94 * @flush_tag: tag of request being flushed (for flush requests) 95 * @wq: wait_queue for the client to block on for this request 96 * @tc: the request fcall structure 97 * @rc: the response fcall structure 98 * @aux: transport specific data (provided for trans_fd migration) 99 * @req_list: link for higher level objects to chain requests 100 * 101 * Transport use an array to track outstanding requests 102 * instead of a list. While this may incurr overhead during initial 103 * allocation or expansion, it makes request lookup much easier as the 104 * tag id is a index into an array. (We use tag+1 so that we can accommodate 105 * the -1 tag for the T_VERSION request). 106 * This also has the nice effect of only having to allocate wait_queues 107 * once, instead of constantly allocating and freeing them. Its possible 108 * other resources could benefit from this scheme as well. 109 * 110 */ 111 112 struct p9_req_t { 113 int status; 114 int t_err; 115 wait_queue_head_t *wq; 116 struct p9_fcall *tc; 117 struct p9_fcall *rc; 118 void *aux; 119 120 struct list_head req_list; 121 }; 122 123 /** 124 * struct p9_client - per client instance state 125 * @lock: protect @fidlist 126 * @msize: maximum data size negotiated by protocol 127 * @dotu: extension flags negotiated by protocol 128 * @proto_version: 9P protocol version to use 129 * @trans_mod: module API instantiated with this client 130 * @trans: tranport instance state and API 131 * @conn: connection state information used by trans_fd 132 * @fidpool: fid handle accounting for session 133 * @fidlist: List of active fid handles 134 * @tagpool - transaction id accounting for session 135 * @reqs - 2D array of requests 136 * @max_tag - current maximum tag id allocated 137 * 138 * The client structure is used to keep track of various per-client 139 * state that has been instantiated. 140 * In order to minimize per-transaction overhead we use a 141 * simple array to lookup requests instead of a hash table 142 * or linked list. In order to support larger number of 143 * transactions, we make this a 2D array, allocating new rows 144 * when we need to grow the total number of the transactions. 145 * 146 * Each row is 256 requests and we'll support up to 256 rows for 147 * a total of 64k concurrent requests per session. 148 * 149 * Bugs: duplicated data and potentially unnecessary elements. 150 */ 151 152 struct p9_client { 153 spinlock_t lock; /* protect client structure */ 154 unsigned int msize; 155 unsigned char proto_version; 156 struct p9_trans_module *trans_mod; 157 enum p9_trans_status status; 158 void *trans; 159 struct p9_conn *conn; 160 161 struct p9_idpool *fidpool; 162 struct list_head fidlist; 163 164 struct p9_idpool *tagpool; 165 struct p9_req_t *reqs[P9_ROW_MAXTAG]; 166 int max_tag; 167 }; 168 169 /** 170 * struct p9_fid - file system entity handle 171 * @clnt: back pointer to instantiating &p9_client 172 * @fid: numeric identifier for this handle 173 * @mode: current mode of this fid (enum?) 174 * @qid: the &p9_qid server identifier this handle points to 175 * @iounit: the server reported maximum transaction size for this file 176 * @uid: the numeric uid of the local user who owns this handle 177 * @rdir: readdir accounting structure (allocated on demand) 178 * @flist: per-client-instance fid tracking 179 * @dlist: per-dentry fid tracking 180 * 181 * TODO: This needs lots of explanation. 182 */ 183 184 struct p9_fid { 185 struct p9_client *clnt; 186 u32 fid; 187 int mode; 188 struct p9_qid qid; 189 u32 iounit; 190 kuid_t uid; 191 192 void *rdir; 193 194 struct list_head flist; 195 struct hlist_node dlist; /* list of all fids attached to a dentry */ 196 }; 197 198 /** 199 * struct p9_dirent - directory entry structure 200 * @qid: The p9 server qid for this dirent 201 * @d_off: offset to the next dirent 202 * @d_type: type of file 203 * @d_name: file name 204 */ 205 206 struct p9_dirent { 207 struct p9_qid qid; 208 u64 d_off; 209 unsigned char d_type; 210 char d_name[256]; 211 }; 212 213 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb); 214 int p9_client_rename(struct p9_fid *fid, struct p9_fid *newdirfid, 215 const char *name); 216 int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name, 217 struct p9_fid *newdirfid, const char *new_name); 218 struct p9_client *p9_client_create(const char *dev_name, char *options); 219 void p9_client_destroy(struct p9_client *clnt); 220 void p9_client_disconnect(struct p9_client *clnt); 221 void p9_client_begin_disconnect(struct p9_client *clnt); 222 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid, 223 char *uname, kuid_t n_uname, char *aname); 224 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname, 225 char **wnames, int clone); 226 int p9_client_open(struct p9_fid *fid, int mode); 227 int p9_client_fcreate(struct p9_fid *fid, char *name, u32 perm, int mode, 228 char *extension); 229 int p9_client_link(struct p9_fid *fid, struct p9_fid *oldfid, char *newname); 230 int p9_client_symlink(struct p9_fid *fid, char *name, char *symname, kgid_t gid, 231 struct p9_qid *qid); 232 int p9_client_create_dotl(struct p9_fid *ofid, char *name, u32 flags, u32 mode, 233 kgid_t gid, struct p9_qid *qid); 234 int p9_client_clunk(struct p9_fid *fid); 235 int p9_client_fsync(struct p9_fid *fid, int datasync); 236 int p9_client_remove(struct p9_fid *fid); 237 int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags); 238 int p9_client_read(struct p9_fid *fid, char *data, char __user *udata, 239 u64 offset, u32 count); 240 int p9_client_write(struct p9_fid *fid, char *data, const char __user *udata, 241 u64 offset, u32 count); 242 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset); 243 int p9dirent_read(struct p9_client *clnt, char *buf, int len, 244 struct p9_dirent *dirent); 245 struct p9_wstat *p9_client_stat(struct p9_fid *fid); 246 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst); 247 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *attr); 248 249 struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid, 250 u64 request_mask); 251 252 int p9_client_mknod_dotl(struct p9_fid *oldfid, char *name, int mode, 253 dev_t rdev, kgid_t gid, struct p9_qid *); 254 int p9_client_mkdir_dotl(struct p9_fid *fid, char *name, int mode, 255 kgid_t gid, struct p9_qid *); 256 int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status); 257 int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *fl); 258 struct p9_req_t *p9_tag_lookup(struct p9_client *, u16); 259 void p9_client_cb(struct p9_client *c, struct p9_req_t *req); 260 261 int p9_parse_header(struct p9_fcall *, int32_t *, int8_t *, int16_t *, int); 262 int p9stat_read(struct p9_client *, char *, int, struct p9_wstat *); 263 void p9stat_free(struct p9_wstat *); 264 265 int p9_is_proto_dotu(struct p9_client *clnt); 266 int p9_is_proto_dotl(struct p9_client *clnt); 267 struct p9_fid *p9_client_xattrwalk(struct p9_fid *, const char *, u64 *); 268 int p9_client_xattrcreate(struct p9_fid *, const char *, u64, int); 269 int p9_client_readlink(struct p9_fid *fid, char **target); 270 271 #endif /* NET_9P_CLIENT_H */ 272