/* SPDX-License-Identifier: GPL-2.0-only */ /* * 9P Client Definitions * * Copyright (C) 2008 by Eric Van Hensbergen * Copyright (C) 2007 by Latchesar Ionkov */ #ifndef NET_9P_CLIENT_H #define NET_9P_CLIENT_H #include #include #include /* Number of requests per row */ #define P9_ROW_MAXTAG 255 /* DEFAULT MSIZE = 32 pages worth of payload + P9_HDRSZ + * room for write (16 extra) or read (11 extra) operands. */ #define DEFAULT_MSIZE ((128 * 1024) + P9_IOHDRSZ) /** 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_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 */ enum p9_req_status_t { 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 * @wq: wait_queue for the client to block on for this request * @tc: the request fcall structure * @rc: the response fcall structure * @req_list: link for higher level objects to chain requests */ struct p9_req_t { int status; int t_err; refcount_t refcount; wait_queue_head_t wq; struct p9_fcall tc; struct p9_fcall rc; struct list_head req_list; }; /** * struct p9_client - per client instance state * @lock: protect @fids and @reqs * @msize: maximum data size negotiated by protocol * @proto_version: 9P protocol version to use * @trans_mod: module API instantiated with this client * @status: connection state * @trans: tranport instance state and API * @fids: All active FID handles * @reqs: All active requests. * @name: node name used as client id * * The client structure is used to keep track of various per-client * state that has been instantiated. */ struct p9_client { spinlock_t lock; unsigned int msize; unsigned char proto_version; struct p9_trans_module *trans_mod; enum p9_trans_status status; void *trans; struct kmem_cache *fcall_cache; union { struct { int rfd; int wfd; } fd; struct { u16 port; bool privport; } tcp; } trans_opts; struct idr fids; struct idr reqs; char name[__NEW_UTS_LEN + 1]; }; /** * struct p9_fd_opts - holds client options during parsing * @msize: maximum data size negotiated by protocol * @prot-Oversion: 9P protocol version to use * @trans_mod: module API instantiated with this client * * These parsed options get transferred into client in * apply_client_options() */ struct p9_client_opts { unsigned int msize; unsigned char proto_version; struct p9_trans_module *trans_mod; }; /** * struct p9_fd_opts - per-transport options for fd transport * @rfd: file descriptor for reading (trans=fd) * @wfd: file descriptor for writing (trans=fd) * @port: port to connect to (trans=tcp) * @privport: port is privileged */ struct p9_fd_opts { int rfd; int wfd; u16 port; bool privport; }; /** * struct p9_rdma_opts - Collection of mount options for rdma transport * @port: port of connection * @privport: Whether a privileged port may be used * @sq_depth: The requested depth of the SQ. This really doesn't need * to be any deeper than the number of threads used in the client * @rq_depth: The depth of the RQ. Should be greater than or equal to SQ depth * @timeout: Time to wait in msecs for CM events */ struct p9_rdma_opts { short port; bool privport; int sq_depth; int rq_depth; long timeout; }; /** * struct p9_session_opts - holds parsed options for v9fs_session_info * @flags: session options of type &p9_session_flags * @nodev: set to 1 to disable device mapping * @debug: debug level * @afid: authentication handle * @cache: cache mode of type &p9_cache_bits * @cachetag: the tag of the cache associated with this session * @uname: string user name to mount hierarchy as * @aname: mount specifier for remote hierarchy * @dfltuid: default numeric userid to mount hierarchy as * @dfltgid: default numeric groupid to mount hierarchy as * @uid: if %V9FS_ACCESS_SINGLE, the numeric uid which mounted the hierarchy * @session_lock_timeout: retry interval for blocking locks * * This strucure holds options which are parsed and will be transferred * to the v9fs_session_info structure when mounted, and therefore largely * duplicates struct v9fs_session_info. */ struct p9_session_opts { unsigned int flags; unsigned char nodev; unsigned short debug; unsigned int afid; unsigned int cache; #ifdef CONFIG_9P_FSCACHE char *cachetag; #endif char *uname; char *aname; kuid_t dfltuid; kgid_t dfltgid; kuid_t uid; long session_lock_timeout; }; /* Used by mount API to store parsed mount options */ struct v9fs_context { struct p9_client_opts client_opts; struct p9_fd_opts fd_opts; struct p9_rdma_opts rdma_opts; struct p9_session_opts session_opts; }; /** * 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) * @dlist: per-dentry fid tracking * * TODO: This needs lots of explanation. */ enum fid_source { FID_FROM_OTHER, FID_FROM_INODE, FID_FROM_DENTRY, }; struct p9_fid { struct p9_client *clnt; u32 fid; refcount_t count; int mode; struct p9_qid qid; u32 iounit; kuid_t uid; void *rdir; struct hlist_node dlist; /* list of all fids attached to a dentry */ struct hlist_node ilist; }; /** * 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_show_client_options(struct seq_file *m, struct p9_client *clnt); 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(struct fs_context *fc); 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, const char *uname, kuid_t n_uname, const char *aname); struct p9_fid *p9_client_walk(struct p9_fid *oldfid, uint16_t nwname, const unsigned char * const *wnames, int clone); int p9_client_open(struct p9_fid *fid, int mode); int p9_client_fcreate(struct p9_fid *fid, const char *name, u32 perm, int mode, char *extension); int p9_client_link(struct p9_fid *fid, struct p9_fid *oldfid, const char *newname); int p9_client_symlink(struct p9_fid *fid, const char *name, const char *symname, kgid_t gid, struct p9_qid *qid); int p9_client_create_dotl(struct p9_fid *ofid, const 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_read_once(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); struct netfs_io_subrequest; void p9_client_write_subreq(struct netfs_io_subrequest *subreq); 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, const char *name, int mode, dev_t rdev, kgid_t gid, struct p9_qid *qid); int p9_client_mkdir_dotl(struct p9_fid *fid, const char *name, int mode, kgid_t gid, struct p9_qid *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); void p9_fcall_fini(struct p9_fcall *fc); struct p9_req_t *p9_tag_lookup(struct p9_client *c, u16 tag); static inline void p9_req_get(struct p9_req_t *r) { refcount_inc(&r->refcount); } static inline int p9_req_try_get(struct p9_req_t *r) { return refcount_inc_not_zero(&r->refcount); } int p9_req_put(struct p9_client *c, struct p9_req_t *r); /* We cannot have the real tracepoints in header files, * use a wrapper function */ DECLARE_TRACEPOINT(9p_fid_ref); void do_trace_9p_fid_get(struct p9_fid *fid); void do_trace_9p_fid_put(struct p9_fid *fid); /* fid reference counting helpers: * - fids used for any length of time should always be referenced through * p9_fid_get(), and released with p9_fid_put() * - v9fs_fid_lookup() or similar will automatically call get for you * and also require a put * - the *_fid_add() helpers will stash the fid in the inode, * at which point it is the responsibility of evict_inode() * to call the put * - the last put will automatically send a clunk to the server */ static inline struct p9_fid *p9_fid_get(struct p9_fid *fid) { if (tracepoint_enabled(9p_fid_ref)) do_trace_9p_fid_get(fid); refcount_inc(&fid->count); return fid; } static inline int p9_fid_put(struct p9_fid *fid) { if (!fid || IS_ERR(fid)) return 0; if (tracepoint_enabled(9p_fid_ref)) do_trace_9p_fid_put(fid); if (!refcount_dec_and_test(&fid->count)) return 0; return p9_client_clunk(fid); } void p9_client_cb(struct p9_client *c, struct p9_req_t *req, int status); int p9_parse_header(struct p9_fcall *pdu, int32_t *size, int8_t *type, int16_t *tag, int rewind); int p9stat_read(struct p9_client *clnt, char *buf, int len, struct p9_wstat *st); void p9stat_free(struct p9_wstat *stbuf); 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 *file_fid, const char *attr_name, u64 *attr_size); int p9_client_xattrcreate(struct p9_fid *fid, const char *name, u64 attr_size, int flags); int p9_client_readlink(struct p9_fid *fid, char **target); int p9_client_init(void); void p9_client_exit(void); #endif /* NET_9P_CLIENT_H */