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Diffstat (limited to 'kernel/include/net/9p/client.h')
| -rw-r--r-- | kernel/include/net/9p/client.h | 272 |
1 files changed, 272 insertions, 0 deletions
diff --git a/kernel/include/net/9p/client.h b/kernel/include/net/9p/client.h new file mode 100644 index 000000000..c6b97e58c --- /dev/null +++ b/kernel/include/net/9p/client.h @@ -0,0 +1,272 @@ +/* + * 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_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_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 + * @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_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]; +}; + +struct iov_iter; + +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, u64 offset, struct iov_iter *to, int *err); +int p9_client_write(struct p9_fid *fid, u64 offset, struct iov_iter *from, int *err); +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 status); + +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 */ |