From 119e9db233ad0f4cbd4cfb9f9385a7bca378b37d Mon Sep 17 00:00:00 2001 From: Zeng Chi Date: Mon, 21 Sep 2026 18:24:42 +0800 Subject: KVM: Don't pre-reserve xarray entries when storing empty/NULL attributes Skip the xarray reservation loop when clearing all memory attributes, as storing NULL only erases the entry and never needs to allocate, so no reservation (and no cleanup of a failed one) is required in that case. Suggested-by: Sean Christopherson Cc: David Ballesteros Signed-off-by: Zeng Chi Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com [sean: split to separate patch] Signed-off-by: Sean Christopherson --- include/net/9p/9p.h | 597 +++++++++++++++++++++++++++++++++++++++++++++ include/net/9p/client.h | 400 ++++++++++++++++++++++++++++++ include/net/9p/transport.h | 80 ++++++ 3 files changed, 1077 insertions(+) create mode 100644 include/net/9p/9p.h create mode 100644 include/net/9p/client.h create mode 100644 include/net/9p/transport.h (limited to 'include/net/9p') diff --git a/include/net/9p/9p.h b/include/net/9p/9p.h new file mode 100644 index 000000000..fd7a034b8 --- /dev/null +++ b/include/net/9p/9p.h @@ -0,0 +1,597 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * 9P protocol definitions. + * + * Copyright (C) 2005 by Latchesar Ionkov + * Copyright (C) 2004 by Eric Van Hensbergen + * Copyright (C) 2002 by Ron Minnich + */ + +#ifndef NET_9P_H +#define NET_9P_H + +/** + * enum p9_debug_flags - bits for mount time debug parameter + * @P9_DEBUG_ERROR: more verbose error messages including original error string + * @P9_DEBUG_9P: 9P protocol tracing + * @P9_DEBUG_VFS: VFS API tracing + * @P9_DEBUG_CONV: protocol conversion tracing + * @P9_DEBUG_MUX: trace management of concurrent transactions + * @P9_DEBUG_TRANS: transport tracing + * @P9_DEBUG_SLABS: memory management tracing + * @P9_DEBUG_FCALL: verbose dump of protocol messages + * @P9_DEBUG_FID: fid allocation/deallocation tracking + * @P9_DEBUG_PKT: packet marshalling/unmarshalling + * @P9_DEBUG_FSC: FS-cache tracing + * @P9_DEBUG_VPKT: Verbose packet debugging (full packet dump) + * @P9_DEBUG_CACHE: cache operations tracing + * @P9_DEBUG_MMAP: memory-mapped I/O tracing + * + * These flags are passed at mount time to turn on various levels of + * verbosity and tracing which will be output to the system logs. + */ + +enum p9_debug_flags { + P9_DEBUG_ERROR = (1<<0), + P9_DEBUG_9P = (1<<2), + P9_DEBUG_VFS = (1<<3), + P9_DEBUG_CONV = (1<<4), + P9_DEBUG_MUX = (1<<5), + P9_DEBUG_TRANS = (1<<6), + P9_DEBUG_SLABS = (1<<7), + P9_DEBUG_FCALL = (1<<8), + P9_DEBUG_FID = (1<<9), + P9_DEBUG_PKT = (1<<10), + P9_DEBUG_FSC = (1<<11), + P9_DEBUG_VPKT = (1<<12), + P9_DEBUG_CACHE = (1<<13), + P9_DEBUG_MMAP = (1<<14), +}; + +#ifdef CONFIG_NET_9P_DEBUG +extern unsigned int p9_debug_level; +__printf(3, 4) +void _p9_debug(enum p9_debug_flags level, const char *func, + const char *fmt, ...); +#define p9_debug(level, fmt, ...) \ + _p9_debug(level, __func__, fmt, ##__VA_ARGS__) +#else +#define p9_debug(level, fmt, ...) \ + no_printk(fmt, ##__VA_ARGS__) +#endif + +/** + * enum p9_msg_t - 9P message types + * @P9_TLERROR: not used + * @P9_RLERROR: response for any failed request for 9P2000.L + * @P9_TSTATFS: file system status request + * @P9_RSTATFS: file system status response + * @P9_TSYMLINK: make symlink request + * @P9_RSYMLINK: make symlink response + * @P9_TMKNOD: create a special file object request + * @P9_RMKNOD: create a special file object response + * @P9_TLOPEN: open a file for I/O (9P2000.L) + * @P9_RLOPEN: response with qid and iounit (9P2000.L) + * @P9_TLCREATE: prepare a handle for I/O on an new file for 9P2000.L + * @P9_RLCREATE: response with file access information for 9P2000.L + * @P9_TRENAME: rename request + * @P9_RRENAME: rename response + * @P9_TREADLINK: read symbolic link target (9P2000.L) + * @P9_RREADLINK: response with symbolic link target (9P2000.L) + * @P9_TGETATTR: get file attributes request (9P2000.L) + * @P9_RGETATTR: get file attributes response (9P2000.L) + * @P9_TSETATTR: set file attributes request (9P2000.L) + * @P9_RSETATTR: set file attributes response (9P2000.L) + * @P9_TXATTRWALK: prepare to read/list extended attributes (9P2000.L) + * @P9_RXATTRWALK: response with extended attribute size (9P2000.L) + * @P9_TXATTRCREATE: prepare to set extended attribute (9P2000.L) + * @P9_RXATTRCREATE: set extended attribute response (9P2000.L) + * @P9_TREADDIR: read directory entries request (9P2000.L) + * @P9_RREADDIR: read directory entries response (9P2000.L) + * @P9_TFSYNC: flush cached file data to storage request (9P2000.L) + * @P9_RFSYNC: flush cached file data to storage response (9P2000.L) + * @P9_TLOCK: acquire or release a POSIX record lock (9P2000.L) + * @P9_RLOCK: POSIX record lock response (9P2000.L) + * @P9_TGETLOCK: test for existence of POSIX record lock (9P2000.L) + * @P9_RGETLOCK: POSIX record lock test response (9P2000.L) + * @P9_TLINK: create a hard link (9P2000.L) + * @P9_RLINK: hard link response (9P2000.L) + * @P9_TRENAMEAT: safely rename across directories (9P2000.L) + * @P9_RRENAMEAT: rename response (9P2000.L) + * @P9_TUNLINKAT: unlink a file or directory (9P2000.L) + * @P9_RUNLINKAT: unlink response (9P2000.L) + * @P9_TMKDIR: create a directory request (9P2000.L) + * @P9_RMKDIR: create a directory response (9P2000.L) + * @P9_TVERSION: negotiate protocol version and message size + * @P9_RVERSION: version handshake response + * @P9_TAUTH: request to establish authentication channel + * @P9_RAUTH: response with authentication information + * @P9_TATTACH: establish user access to file service + * @P9_RATTACH: response with top level handle to file hierarchy + * @P9_TERROR: not used + * @P9_RERROR: response for any failed request + * @P9_TFLUSH: request to abort a previous request + * @P9_RFLUSH: response when previous request has been cancelled + * @P9_TWALK: descend a directory hierarchy + * @P9_RWALK: response with new handle for position within hierarchy + * @P9_TOPEN: prepare a handle for I/O on an existing file + * @P9_ROPEN: response with file access information + * @P9_TCREATE: prepare a handle for I/O on a new file + * @P9_RCREATE: response with file access information + * @P9_TREAD: request to transfer data from a file or directory + * @P9_RREAD: response with data requested + * @P9_TWRITE: reuqest to transfer data to a file + * @P9_RWRITE: response with out much data was transferred to file + * @P9_TCLUNK: forget about a handle to an entity within the file system + * @P9_RCLUNK: response when server has forgotten about the handle + * @P9_TREMOVE: request to remove an entity from the hierarchy + * @P9_RREMOVE: response when server has removed the entity + * @P9_TSTAT: request file entity attributes + * @P9_RSTAT: response with file entity attributes + * @P9_TWSTAT: request to update file entity attributes + * @P9_RWSTAT: response when file entity attributes are updated + * + * There are 14 basic operations in 9P2000, paired as + * requests and responses. The one special case is ERROR + * as there is no @P9_TERROR request for clients to transmit to + * the server, but the server may respond to any other request + * with an @P9_RERROR. + * + * See Also: http://plan9.bell-labs.com/sys/man/5/INDEX.html + */ + +enum p9_msg_t { + P9_TLERROR = 6, + P9_RLERROR, + P9_TSTATFS = 8, + P9_RSTATFS, + P9_TLOPEN = 12, + P9_RLOPEN, + P9_TLCREATE = 14, + P9_RLCREATE, + P9_TSYMLINK = 16, + P9_RSYMLINK, + P9_TMKNOD = 18, + P9_RMKNOD, + P9_TRENAME = 20, + P9_RRENAME, + P9_TREADLINK = 22, + P9_RREADLINK, + P9_TGETATTR = 24, + P9_RGETATTR, + P9_TSETATTR = 26, + P9_RSETATTR, + P9_TXATTRWALK = 30, + P9_RXATTRWALK, + P9_TXATTRCREATE = 32, + P9_RXATTRCREATE, + P9_TREADDIR = 40, + P9_RREADDIR, + P9_TFSYNC = 50, + P9_RFSYNC, + P9_TLOCK = 52, + P9_RLOCK, + P9_TGETLOCK = 54, + P9_RGETLOCK, + P9_TLINK = 70, + P9_RLINK, + P9_TMKDIR = 72, + P9_RMKDIR, + P9_TRENAMEAT = 74, + P9_RRENAMEAT, + P9_TUNLINKAT = 76, + P9_RUNLINKAT, + P9_TVERSION = 100, + P9_RVERSION, + P9_TAUTH = 102, + P9_RAUTH, + P9_TATTACH = 104, + P9_RATTACH, + P9_TERROR = 106, + P9_RERROR, + P9_TFLUSH = 108, + P9_RFLUSH, + P9_TWALK = 110, + P9_RWALK, + P9_TOPEN = 112, + P9_ROPEN, + P9_TCREATE = 114, + P9_RCREATE, + P9_TREAD = 116, + P9_RREAD, + P9_TWRITE = 118, + P9_RWRITE, + P9_TCLUNK = 120, + P9_RCLUNK, + P9_TREMOVE = 122, + P9_RREMOVE, + P9_TSTAT = 124, + P9_RSTAT, + P9_TWSTAT = 126, + P9_RWSTAT, +}; + +/** + * enum p9_open_mode_t - 9P open modes + * @P9_OREAD: open file for reading only + * @P9_OWRITE: open file for writing only + * @P9_ORDWR: open file for reading or writing + * @P9_OEXEC: open file for execution + * @P9_OTRUNC: truncate file to zero-length before opening it + * @P9_OREXEC: close the file when an exec(2) system call is made + * @P9_ORCLOSE: remove the file when the file is closed + * @P9_OAPPEND: open the file and seek to the end + * @P9_OEXCL: only create a file, do not open it + * @P9L_MODE_MASK: mask for protocol mode bits (client-side only) + * @P9L_DIRECT: disable client-side caching for this file + * @P9L_NOWRITECACHE: disable write caching for this file + * @P9L_LOOSE: enable loose cache consistency + * + * 9P open modes differ slightly from Posix standard modes. + * In particular, there are extra modes which specify different + * semantic behaviors than may be available on standard Posix + * systems. For example, @P9_OREXEC and @P9_ORCLOSE are modes that + * most likely will not be issued from the Linux VFS client, but may + * be supported by servers. + * + * See Also: http://plan9.bell-labs.com/magic/man2html/2/open + */ + +enum p9_open_mode_t { + P9_OREAD = 0x00, + P9_OWRITE = 0x01, + P9_ORDWR = 0x02, + P9_OEXEC = 0x03, + P9_OTRUNC = 0x10, + P9_OREXEC = 0x20, + P9_ORCLOSE = 0x40, + P9_OAPPEND = 0x80, + P9_OEXCL = 0x1000, + P9L_MODE_MASK = 0x1FFF, /* don't send anything under this to server */ + P9L_DIRECT = 0x2000, /* cache disabled */ + P9L_NOWRITECACHE = 0x4000, /* no write caching */ + P9L_LOOSE = 0x8000, /* loose cache */ +}; + +/** + * enum p9_perm_t - 9P permissions + * @P9_DMDIR: mode bit for directories + * @P9_DMAPPEND: mode bit for is append-only + * @P9_DMEXCL: mode bit for excluse use (only one open handle allowed) + * @P9_DMMOUNT: mode bit for mount points + * @P9_DMAUTH: mode bit for authentication file + * @P9_DMTMP: mode bit for non-backed-up files + * @P9_DMSYMLINK: mode bit for symbolic links (9P2000.u) + * @P9_DMLINK: mode bit for hard-link (9P2000.u) + * @P9_DMDEVICE: mode bit for device files (9P2000.u) + * @P9_DMNAMEDPIPE: mode bit for named pipe (9P2000.u) + * @P9_DMSOCKET: mode bit for socket (9P2000.u) + * @P9_DMSETUID: mode bit for setuid (9P2000.u) + * @P9_DMSETGID: mode bit for setgid (9P2000.u) + * @P9_DMSETVTX: mode bit for sticky bit (9P2000.u) + * + * 9P permissions differ slightly from Posix standard modes. + * + * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat + */ +enum p9_perm_t { + P9_DMDIR = 0x80000000, + P9_DMAPPEND = 0x40000000, + P9_DMEXCL = 0x20000000, + P9_DMMOUNT = 0x10000000, + P9_DMAUTH = 0x08000000, + P9_DMTMP = 0x04000000, +/* 9P2000.u extensions */ + P9_DMSYMLINK = 0x02000000, + P9_DMLINK = 0x01000000, + P9_DMDEVICE = 0x00800000, + P9_DMNAMEDPIPE = 0x00200000, + P9_DMSOCKET = 0x00100000, + P9_DMSETUID = 0x00080000, + P9_DMSETGID = 0x00040000, + P9_DMSETVTX = 0x00010000, +}; + +/* 9p2000.L open flags */ +#define P9_DOTL_RDONLY 00000000 +#define P9_DOTL_WRONLY 00000001 +#define P9_DOTL_RDWR 00000002 +#define P9_DOTL_NOACCESS 00000003 +#define P9_DOTL_CREATE 00000100 +#define P9_DOTL_EXCL 00000200 +#define P9_DOTL_NOCTTY 00000400 +#define P9_DOTL_TRUNC 00001000 +#define P9_DOTL_APPEND 00002000 +#define P9_DOTL_NONBLOCK 00004000 +#define P9_DOTL_DSYNC 00010000 +#define P9_DOTL_FASYNC 00020000 +#define P9_DOTL_DIRECT 00040000 +#define P9_DOTL_LARGEFILE 00100000 +#define P9_DOTL_DIRECTORY 00200000 +#define P9_DOTL_NOFOLLOW 00400000 +#define P9_DOTL_NOATIME 01000000 +#define P9_DOTL_CLOEXEC 02000000 +#define P9_DOTL_SYNC 04000000 + +/* 9p2000.L at flags */ +#define P9_DOTL_AT_REMOVEDIR 0x200 + +/* 9p2000.L lock type */ +#define P9_LOCK_TYPE_RDLCK 0 +#define P9_LOCK_TYPE_WRLCK 1 +#define P9_LOCK_TYPE_UNLCK 2 + +/** + * enum p9_qid_t - QID types + * @P9_QTDIR: directory + * @P9_QTAPPEND: append-only + * @P9_QTEXCL: excluse use (only one open handle allowed) + * @P9_QTMOUNT: mount points + * @P9_QTAUTH: authentication file + * @P9_QTTMP: non-backed-up files + * @P9_QTSYMLINK: symbolic links (9P2000.u) + * @P9_QTLINK: hard-link (9P2000.u) + * @P9_QTFILE: normal files + * + * QID types are a subset of permissions - they are primarily + * used to differentiate semantics for a file system entity via + * a jump-table. Their value is also the most significant 16 bits + * of the permission_t + * + * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat + */ +enum p9_qid_t { + P9_QTDIR = 0x80, + P9_QTAPPEND = 0x40, + P9_QTEXCL = 0x20, + P9_QTMOUNT = 0x10, + P9_QTAUTH = 0x08, + P9_QTTMP = 0x04, + P9_QTSYMLINK = 0x02, + P9_QTLINK = 0x01, + P9_QTFILE = 0x00, +}; + +/* 9P Magic Numbers */ +#define P9_NOTAG ((u16)(~0)) +#define P9_NOFID ((u32)(~0)) +#define P9_MAXWELEM 16 + +/* Minimal header size: size[4] type[1] tag[2] */ +#define P9_HDRSZ 7 + +/* ample room for Twrite/Rread header */ +#define P9_IOHDRSZ 24 + +/* Room for readdir header */ +#define P9_READDIRHDRSZ 24 + +/* size of header for zero copy read/write */ +#define P9_ZC_HDR_SZ 4096 + +/* maximum length of an error string */ +#define P9_ERRMAX 128 + +/** + * struct p9_qid - file system entity information + * @type: 8-bit type &p9_qid_t + * @version: 16-bit monotonically incrementing version number + * @path: 64-bit per-server-unique ID for a file system element + * + * qids are identifiers used by 9P servers to track file system + * entities. The type is used to differentiate semantics for operations + * on the entity (ie. read means something different on a directory than + * on a file). The path provides a server unique index for an entity + * (roughly analogous to an inode number), while the version is updated + * every time a file is modified and can be used to maintain cache + * coherency between clients and serves. + * Servers will often differentiate purely synthetic entities by setting + * their version to 0, signaling that they should never be cached and + * should be accessed synchronously. + * + * See Also://plan9.bell-labs.com/magic/man2html/2/stat + */ + +struct p9_qid { + u8 type; + u32 version; + u64 path; +}; + +/** + * struct p9_wstat - file system metadata information + * @size: length prefix for this stat structure instance + * @type: the type of the server (equivalent to a major number) + * @dev: the sub-type of the server (equivalent to a minor number) + * @qid: unique id from the server of type &p9_qid + * @mode: Plan 9 format permissions of type &p9_perm_t + * @atime: Last access/read time + * @mtime: Last modify/write time + * @length: file length + * @name: last element of path (aka filename) + * @uid: owner name + * @gid: group owner + * @muid: last modifier + * @extension: area used to encode extended UNIX support + * @n_uid: numeric user id of owner (part of 9p2000.u extension) + * @n_gid: numeric group id (part of 9p2000.u extension) + * @n_muid: numeric user id of laster modifier (part of 9p2000.u extension) + * + * See Also: http://plan9.bell-labs.com/magic/man2html/2/stat + */ + +struct p9_wstat { + u16 size; + u16 type; + u32 dev; + struct p9_qid qid; + u32 mode; + u32 atime; + u32 mtime; + u64 length; + const char *name; + const char *uid; + const char *gid; + const char *muid; + char *extension; /* 9p2000.u extensions */ + kuid_t n_uid; /* 9p2000.u extensions */ + kgid_t n_gid; /* 9p2000.u extensions */ + kuid_t n_muid; /* 9p2000.u extensions */ +}; + +struct p9_stat_dotl { + u64 st_result_mask; + struct p9_qid qid; + u32 st_mode; + kuid_t st_uid; + kgid_t st_gid; + u64 st_nlink; + u64 st_rdev; + u64 st_size; + u64 st_blksize; + u64 st_blocks; + u64 st_atime_sec; + u64 st_atime_nsec; + u64 st_mtime_sec; + u64 st_mtime_nsec; + u64 st_ctime_sec; + u64 st_ctime_nsec; + u64 st_btime_sec; + u64 st_btime_nsec; + u64 st_gen; + u64 st_data_version; +}; + +#define P9_STATS_MODE 0x00000001ULL +#define P9_STATS_NLINK 0x00000002ULL +#define P9_STATS_UID 0x00000004ULL +#define P9_STATS_GID 0x00000008ULL +#define P9_STATS_RDEV 0x00000010ULL +#define P9_STATS_ATIME 0x00000020ULL +#define P9_STATS_MTIME 0x00000040ULL +#define P9_STATS_CTIME 0x00000080ULL +#define P9_STATS_INO 0x00000100ULL +#define P9_STATS_SIZE 0x00000200ULL +#define P9_STATS_BLOCKS 0x00000400ULL + +#define P9_STATS_BTIME 0x00000800ULL +#define P9_STATS_GEN 0x00001000ULL +#define P9_STATS_DATA_VERSION 0x00002000ULL + +#define P9_STATS_BASIC 0x000007ffULL /* Mask for fields up to BLOCKS */ +#define P9_STATS_ALL 0x00003fffULL /* Mask for All fields above */ + +/** + * struct p9_iattr_dotl - P9 inode attribute for setattr + * @valid: bitfield specifying which fields are valid + * same as in struct iattr + * @mode: File permission bits + * @uid: user id of owner + * @gid: group id + * @size: File size + * @atime_sec: Last access time, seconds + * @atime_nsec: Last access time, nanoseconds + * @mtime_sec: Last modification time, seconds + * @mtime_nsec: Last modification time, nanoseconds + */ + +struct p9_iattr_dotl { + u32 valid; + u32 mode; + kuid_t uid; + kgid_t gid; + u64 size; + u64 atime_sec; + u64 atime_nsec; + u64 mtime_sec; + u64 mtime_nsec; +}; + +#define P9_LOCK_SUCCESS 0 +#define P9_LOCK_BLOCKED 1 +#define P9_LOCK_ERROR 2 +#define P9_LOCK_GRACE 3 + +#define P9_LOCK_FLAGS_BLOCK 1 +#define P9_LOCK_FLAGS_RECLAIM 2 + +/* struct p9_flock: POSIX lock structure + * @type - type of lock + * @flags - lock flags + * @start - starting offset of the lock + * @length - number of bytes + * @proc_id - process id which wants to take lock + * @client_id - client id + */ + +struct p9_flock { + u8 type; + u32 flags; + u64 start; + u64 length; + u32 proc_id; + char *client_id; +}; + +/* struct p9_getlock: getlock structure + * @type - type of lock + * @start - starting offset of the lock + * @length - number of bytes + * @proc_id - process id which wants to take lock + * @client_id - client id + */ + +struct p9_getlock { + u8 type; + u64 start; + u64 length; + u32 proc_id; + char *client_id; +}; + +struct p9_rstatfs { + u32 type; + u32 bsize; + u64 blocks; + u64 bfree; + u64 bavail; + u64 files; + u64 ffree; + u64 fsid; + u32 namelen; +}; + +/** + * struct p9_fcall - primary packet structure + * @size: prefixed length of the structure + * @id: protocol operating identifier of type &p9_msg_t + * @tag: transaction id of the request + * @offset: used by marshalling routines to track current position in buffer + * @capacity: used by marshalling routines to track total malloc'd capacity + * @sdata: payload + * @zc: whether zero-copy is used + * + * &p9_fcall represents the structure for all 9P RPC + * transactions. Requests are packaged into fcalls, and reponses + * must be extracted from them. + * + * See Also: http://plan9.bell-labs.com/magic/man2html/2/fcall + */ + +struct p9_fcall { + u32 size; + u8 id; + u16 tag; + + size_t offset; + size_t capacity; + + struct kmem_cache *cache; + u8 *sdata; + bool zc; +}; + +int p9_errstr2errno(char *errstr, int len); + +int p9_error_init(void); +#endif /* NET_9P_H */ diff --git a/include/net/9p/client.h b/include/net/9p/client.h new file mode 100644 index 000000000..55c6cb54b --- /dev/null +++ b/include/net/9p/client.h @@ -0,0 +1,400 @@ +/* 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 + * @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 */ diff --git a/include/net/9p/transport.h b/include/net/9p/transport.h new file mode 100644 index 000000000..a912bbaa8 --- /dev/null +++ b/include/net/9p/transport.h @@ -0,0 +1,80 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Transport Definition + * + * Copyright (C) 2005 by Latchesar Ionkov + * Copyright (C) 2004-2008 by Eric Van Hensbergen + */ + +#ifndef NET_9P_TRANSPORT_H +#define NET_9P_TRANSPORT_H + +#include + +#define P9_DEF_MIN_RESVPORT (665U) +#define P9_DEF_MAX_RESVPORT (1023U) + +#define P9_FD_PORT 564 + +#define P9_RDMA_PORT 5640 +#define P9_RDMA_SQ_DEPTH 32 +#define P9_RDMA_RQ_DEPTH 32 +#define P9_RDMA_TIMEOUT 30000 /* 30 seconds */ + +/** + * struct p9_trans_module - transport module interface + * @list: used to maintain a list of currently available transports + * @name: the human-readable name of the transport + * @maxsize: transport provided maximum packet size + * @pooled_rbuffers: currently only set for RDMA transport which pulls the + * response buffers from a shared pool, and accordingly + * we're less flexible when choosing the response message + * size in this case + * @def: set if this transport should be considered the default + * @supports_vmalloc: set if this transport can work with vmalloc'd buffers + * (non-physically contiguous memory). Transports requiring + * DMA should leave this as false. + * @create: member function to create a new connection on this transport + * @close: member function to discard a connection on this transport + * @request: member function to issue a request to the transport + * @cancel: member function to cancel a request (if it hasn't been sent) + * @cancelled: member function to notify that a cancelled request will not + * receive a reply + * + * This is the basic API for a transport module which is registered by the + * transport module with the 9P core network module and used by the client + * to instantiate a new connection on a transport. + * + * The transport module list is protected by v9fs_trans_lock. + */ + +struct p9_trans_module { + struct list_head list; + char *name; /* name of transport */ + int maxsize; /* max message size of transport */ + bool pooled_rbuffers; + bool def; /* this transport should be default */ + bool supports_vmalloc; /* can work with vmalloc'd buffers */ + struct module *owner; + int (*create)(struct p9_client *client, + struct fs_context *fc); + void (*close)(struct p9_client *client); + int (*request)(struct p9_client *client, struct p9_req_t *req); + int (*cancel)(struct p9_client *client, struct p9_req_t *req); + int (*cancelled)(struct p9_client *client, struct p9_req_t *req); + int (*zc_request)(struct p9_client *client, struct p9_req_t *req, + struct iov_iter *uidata, struct iov_iter *uodata, + int inlen, int outlen, int in_hdr_len); + int (*show_options)(struct seq_file *m, struct p9_client *client); +}; + +void v9fs_register_trans(struct p9_trans_module *m); +void v9fs_unregister_trans(struct p9_trans_module *m); +struct p9_trans_module *v9fs_get_trans_by_name(const char *s); +struct p9_trans_module *v9fs_get_default_trans(void); +void v9fs_put_trans(struct p9_trans_module *m); + +#define MODULE_ALIAS_9P(transport) \ + MODULE_ALIAS("9p-" transport) + +#endif /* NET_9P_TRANSPORT_H */ -- cgit v1.3.1