1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * 9P Client Definitions 4 * 5 * Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com> 6 * Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net> 7 */ 8 9 #ifndef NET_9P_CLIENT_H 10 #define NET_9P_CLIENT_H 11 12 #include <linux/utsname.h> 13 #include <linux/idr.h> 14 15 /* Number of requests per row */ 16 #define P9_ROW_MAXTAG 255 17 18 /** enum p9_proto_versions - 9P protocol versions 19 * @p9_proto_legacy: 9P Legacy mode, pre-9P2000.u 20 * @p9_proto_2000u: 9P2000.u extension 21 * @p9_proto_2000L: 9P2000.L extension 22 */ 23 24 enum p9_proto_versions { 25 p9_proto_legacy, 26 p9_proto_2000u, 27 p9_proto_2000L, 28 }; 29 30 31 /** 32 * enum p9_trans_status - different states of underlying transports 33 * @Connected: transport is connected and healthy 34 * @Disconnected: transport has been disconnected 35 * @Hung: transport is connected by wedged 36 * 37 * This enumeration details the various states a transport 38 * instatiation can be in. 39 */ 40 41 enum p9_trans_status { 42 Connected, 43 BeginDisconnect, 44 Disconnected, 45 Hung, 46 }; 47 48 /** 49 * enum p9_req_status_t - status of a request 50 * @REQ_STATUS_ALLOC: request has been allocated but not sent 51 * @REQ_STATUS_UNSENT: request waiting to be sent 52 * @REQ_STATUS_SENT: request sent to server 53 * @REQ_STATUS_RCVD: response received from server 54 * @REQ_STATUS_FLSHD: request has been flushed 55 * @REQ_STATUS_ERROR: request encountered an error on the client side 56 */ 57 58 enum p9_req_status_t { 59 REQ_STATUS_ALLOC, 60 REQ_STATUS_UNSENT, 61 REQ_STATUS_SENT, 62 REQ_STATUS_RCVD, 63 REQ_STATUS_FLSHD, 64 REQ_STATUS_ERROR, 65 }; 66 67 /** 68 * struct p9_req_t - request slots 69 * @status: status of this request slot 70 * @t_err: transport error 71 * @wq: wait_queue for the client to block on for this request 72 * @tc: the request fcall structure 73 * @rc: the response fcall structure 74 * @req_list: link for higher level objects to chain requests 75 */ 76 struct p9_req_t { 77 int status; 78 int t_err; 79 struct kref refcount; 80 wait_queue_head_t wq; 81 struct p9_fcall tc; 82 struct p9_fcall rc; 83 struct list_head req_list; 84 }; 85 86 /** 87 * struct p9_client - per client instance state 88 * @lock: protect @fids and @reqs 89 * @msize: maximum data size negotiated by protocol 90 * @proto_version: 9P protocol version to use 91 * @trans_mod: module API instantiated with this client 92 * @status: connection state 93 * @trans: tranport instance state and API 94 * @fids: All active FID handles 95 * @reqs: All active requests. 96 * @name: node name used as client id 97 * 98 * The client structure is used to keep track of various per-client 99 * state that has been instantiated. 100 */ 101 struct p9_client { 102 spinlock_t lock; 103 unsigned int msize; 104 unsigned char proto_version; 105 struct p9_trans_module *trans_mod; 106 enum p9_trans_status status; 107 void *trans; 108 struct kmem_cache *fcall_cache; 109 110 union { 111 struct { 112 int rfd; 113 int wfd; 114 } fd; 115 struct { 116 u16 port; 117 bool privport; 118 119 } tcp; 120 } trans_opts; 121 122 struct idr fids; 123 struct idr reqs; 124 125 char name[__NEW_UTS_LEN + 1]; 126 }; 127 128 /** 129 * struct p9_fid - file system entity handle 130 * @clnt: back pointer to instantiating &p9_client 131 * @fid: numeric identifier for this handle 132 * @mode: current mode of this fid (enum?) 133 * @qid: the &p9_qid server identifier this handle points to 134 * @iounit: the server reported maximum transaction size for this file 135 * @uid: the numeric uid of the local user who owns this handle 136 * @rdir: readdir accounting structure (allocated on demand) 137 * @dlist: per-dentry fid tracking 138 * 139 * TODO: This needs lots of explanation. 140 */ 141 enum fid_source { 142 FID_FROM_OTHER, 143 FID_FROM_INODE, 144 FID_FROM_DENTRY, 145 }; 146 147 struct p9_fid { 148 struct p9_client *clnt; 149 u32 fid; 150 refcount_t count; 151 int mode; 152 struct p9_qid qid; 153 u32 iounit; 154 kuid_t uid; 155 156 void *rdir; 157 158 struct hlist_node dlist; /* list of all fids attached to a dentry */ 159 struct hlist_node ilist; 160 }; 161 162 /** 163 * struct p9_dirent - directory entry structure 164 * @qid: The p9 server qid for this dirent 165 * @d_off: offset to the next dirent 166 * @d_type: type of file 167 * @d_name: file name 168 */ 169 170 struct p9_dirent { 171 struct p9_qid qid; 172 u64 d_off; 173 unsigned char d_type; 174 char d_name[256]; 175 }; 176 177 struct iov_iter; 178 179 int p9_show_client_options(struct seq_file *m, struct p9_client *clnt); 180 int p9_client_statfs(struct p9_fid *fid, struct p9_rstatfs *sb); 181 int p9_client_rename(struct p9_fid *fid, struct p9_fid *newdirfid, 182 const char *name); 183 int p9_client_renameat(struct p9_fid *olddirfid, const char *old_name, 184 struct p9_fid *newdirfid, const char *new_name); 185 struct p9_client *p9_client_create(const char *dev_name, char *options); 186 void p9_client_destroy(struct p9_client *clnt); 187 void p9_client_disconnect(struct p9_client *clnt); 188 void p9_client_begin_disconnect(struct p9_client *clnt); 189 struct p9_fid *p9_client_attach(struct p9_client *clnt, struct p9_fid *afid, 190 const char *uname, kuid_t n_uname, const char *aname); 191 struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname, 192 const unsigned char * const *wnames, int clone); 193 int p9_client_open(struct p9_fid *fid, int mode); 194 int p9_client_fcreate(struct p9_fid *fid, const char *name, u32 perm, int mode, 195 char *extension); 196 int p9_client_link(struct p9_fid *fid, struct p9_fid *oldfid, const char *newname); 197 int p9_client_symlink(struct p9_fid *fid, const char *name, const char *symname, 198 kgid_t gid, struct p9_qid *qid); 199 int p9_client_create_dotl(struct p9_fid *ofid, const char *name, u32 flags, u32 mode, 200 kgid_t gid, struct p9_qid *qid); 201 int p9_client_clunk(struct p9_fid *fid); 202 int p9_client_fsync(struct p9_fid *fid, int datasync); 203 int p9_client_remove(struct p9_fid *fid); 204 int p9_client_unlinkat(struct p9_fid *dfid, const char *name, int flags); 205 int p9_client_read(struct p9_fid *fid, u64 offset, struct iov_iter *to, int *err); 206 int p9_client_read_once(struct p9_fid *fid, u64 offset, struct iov_iter *to, 207 int *err); 208 int p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err); 209 int p9_client_readdir(struct p9_fid *fid, char *data, u32 count, u64 offset); 210 int p9dirent_read(struct p9_client *clnt, char *buf, int len, 211 struct p9_dirent *dirent); 212 struct p9_wstat *p9_client_stat(struct p9_fid *fid); 213 int p9_client_wstat(struct p9_fid *fid, struct p9_wstat *wst); 214 int p9_client_setattr(struct p9_fid *fid, struct p9_iattr_dotl *attr); 215 216 struct p9_stat_dotl *p9_client_getattr_dotl(struct p9_fid *fid, 217 u64 request_mask); 218 219 int p9_client_mknod_dotl(struct p9_fid *oldfid, const char *name, int mode, 220 dev_t rdev, kgid_t gid, struct p9_qid *qid); 221 int p9_client_mkdir_dotl(struct p9_fid *fid, const char *name, int mode, 222 kgid_t gid, struct p9_qid *qid); 223 int p9_client_lock_dotl(struct p9_fid *fid, struct p9_flock *flock, u8 *status); 224 int p9_client_getlock_dotl(struct p9_fid *fid, struct p9_getlock *fl); 225 void p9_fcall_fini(struct p9_fcall *fc); 226 struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag); 227 228 static inline void p9_req_get(struct p9_req_t *r) 229 { 230 kref_get(&r->refcount); 231 } 232 233 static inline int p9_req_try_get(struct p9_req_t *r) 234 { 235 return kref_get_unless_zero(&r->refcount); 236 } 237 238 int p9_req_put(struct p9_req_t *r); 239 240 void p9_client_cb(struct p9_client *c, struct p9_req_t *req, int status); 241 242 int p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, 243 int16_t *tag, int rewind); 244 int p9stat_read(struct p9_client *clnt, char *buf, int len, 245 struct p9_wstat *st); 246 void p9stat_free(struct p9_wstat *stbuf); 247 248 int p9_is_proto_dotu(struct p9_client *clnt); 249 int p9_is_proto_dotl(struct p9_client *clnt); 250 struct p9_fid *p9_client_xattrwalk(struct p9_fid *file_fid, 251 const char *attr_name, u64 *attr_size); 252 int p9_client_xattrcreate(struct p9_fid *fid, const char *name, 253 u64 attr_size, int flags); 254 int p9_client_readlink(struct p9_fid *fid, char **target); 255 256 int p9_client_init(void); 257 void p9_client_exit(void); 258 259 #endif /* NET_9P_CLIENT_H */ 260