/* SPDX-License-Identifier: GPL-2.0-only *//* * 9P Client Definitions * *  Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com> *  Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net> */ #ifndef NET_9P_CLIENT_H#define NET_9P_CLIENT_H #include <linux/utsname.h>#include <linux/idr.h>#include <linux/tracepoint-defs.h> /* 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 * @ndentry_timeout_ms: Negative dentry lookup cache retention time in ms * * 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;	unsigned int ndentry_timeout_ms;#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 */