/* * linux/fs/9p/v9fs.c * * This file contains functions assisting in mapping VFS to 9P2000 * * Copyright (C) 2004 by Eric Van Hensbergen * Copyright (C) 2002 by Ron Minnich * * 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 * */ #include #include #include #include #include #include #include #include #include #include #include "v9fs.h" #include "v9fs_vfs.h" /* * Dynamic Transport Registration Routines * */ static LIST_HEAD(v9fs_trans_list); static struct p9_trans_module *v9fs_default_trans; /** * v9fs_register_trans - register a new transport with 9p * @m - structure describing the transport module and entry points * */ void v9fs_register_trans(struct p9_trans_module *m) { list_add_tail(&m->list, &v9fs_trans_list); if (m->def) v9fs_default_trans = m; } EXPORT_SYMBOL(v9fs_register_trans); /** * v9fs_match_trans - match transport versus registered transports * @arg: string identifying transport * */ static struct p9_trans_module *v9fs_match_trans(const substring_t *name) { struct list_head *p; struct p9_trans_module *t = NULL; list_for_each(p, &v9fs_trans_list) { t = list_entry(p, struct p9_trans_module, list); if (strncmp(t->name, name->from, name->to-name->from) == 0) { P9_DPRINTK(P9_DEBUG_TRANS, "trans=%s\n", t->name); break; } } return t; } /* * Option Parsing (code inspired by NFS code) * NOTE: each transport will parse its own options */ enum { /* Options that take integer arguments */ Opt_debug, Opt_msize, Opt_dfltuid, Opt_dfltgid, Opt_afid, /* String options */ Opt_uname, Opt_remotename, Opt_trans, /* Options that take no arguments */ Opt_legacy, Opt_nodevmap, /* Cache options */ Opt_cache_loose, /* Error token */ Opt_err }; static match_table_t tokens = { {Opt_debug, "debug=%x"}, {Opt_msize, "msize=%u"}, {Opt_dfltuid, "dfltuid=%u"}, {Opt_dfltgid, "dfltgid=%u"}, {Opt_afid, "afid=%u"}, {Opt_uname, "uname=%s"}, {Opt_remotename, "aname=%s"}, {Opt_trans, "trans=%s"}, {Opt_legacy, "noextend"}, {Opt_nodevmap, "nodevmap"}, {Opt_cache_loose, "cache=loose"}, {Opt_cache_loose, "loose"}, {Opt_err, NULL} }; /** * v9fs_parse_options - parse mount options into session structure * @options: options string passed from mount * @v9ses: existing v9fs session information * */ static void v9fs_parse_options(struct v9fs_session_info *v9ses) { char *options = v9ses->options; substring_t args[MAX_OPT_ARGS]; char *p; int option; int ret; /* setup defaults */ v9ses->maxdata = 8192; v9ses->flags = V9FS_EXTENDED; v9ses->afid = ~0; v9ses->debug = 0; v9ses->cache = 0; v9ses->trans = v9fs_default_trans; if (!options) return; while ((p = strsep(&options, ",")) != NULL) { int token; if (!*p) continue; token = match_token(p, tokens, args); if (token < Opt_uname) { if ((ret = match_int(&args[0], &option)) < 0) { P9_DPRINTK(P9_DEBUG_ERROR, "integer field, but no integer?\n"); continue; } } switch (token) { case Opt_debug: v9ses->debug = option; #ifdef CONFIG_NET_9P_DEBUG p9_debug_level = option; #endif break; case Opt_msize: v9ses->maxdata = option; break; case Opt_dfltuid: v9ses->dfltuid = option; break; case Opt_dfltgid: v9ses->dfltgid = option; break; case Opt_afid: v9ses->afid = option; break; case Opt_trans: v9ses->trans = v9fs_match_trans(&args[0]); break; case Opt_uname: match_strcpy(v9ses->name, &args[0]); break; case Opt_remotename: match_strcpy(v9ses->remotename, &args[0]); break; case Opt_legacy: v9ses->flags &= ~V9FS_EXTENDED; break; case Opt_nodevmap: v9ses->nodev = 1; break; case Opt_cache_loose: v9ses->cache = CACHE_LOOSE; break; default: continue; } } } /** * v9fs_session_init - initialize session * @v9ses: session information structure * @dev_name: device being mounted * @data: options * */ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses, const char *dev_name, char *data) { int retval = -EINVAL; struct p9_trans *trans = NULL; struct p9_fid *fid; v9ses->name = __getname(); if (!v9ses->name) return ERR_PTR(-ENOMEM); v9ses->remotename = __getname(); if (!v9ses->remotename) { __putname(v9ses->name); return ERR_PTR(-ENOMEM); } strcpy(v9ses->name, V9FS_DEFUSER); strcpy(v9ses->remotename, V9FS_DEFANAME); v9ses->dfltuid = V9FS_DEFUID; v9ses->dfltgid = V9FS_DEFGID; v9ses->options = kstrdup(data, GFP_KERNEL); v9fs_parse_options(v9ses); if ((v9ses->trans == NULL) && !list_empty(&v9fs_trans_list)) v9ses->trans = list_first_entry(&v9fs_trans_list, struct p9_trans_module, list); if (v9ses->trans == NULL) { retval = -EPROTONOSUPPORT; P9_DPRINTK(P9_DEBUG_ERROR, "No transport defined or default transport\n"); goto error; } trans = v9ses->trans->create(dev_name, v9ses->options); if (IS_ERR(trans)) { retval = PTR_ERR(trans); trans = NULL; goto error; } if ((v9ses->maxdata+P9_IOHDRSZ) > v9ses->trans->maxsize) v9ses->maxdata = v9ses->trans->maxsize-P9_IOHDRSZ; v9ses->clnt = p9_client_create(trans, v9ses->maxdata+P9_IOHDRSZ, v9fs_extended(v9ses)); if (IS_ERR(v9ses->clnt)) { retval = PTR_ERR(v9ses->clnt); v9ses->clnt = NULL; P9_DPRINTK(P9_DEBUG_ERROR, "problem initializing 9p client\n"); goto error; } fid = p9_client_attach(v9ses->clnt, NULL, v9ses->name, v9ses->remotename); if (IS_ERR(fid)) { retval = PTR_ERR(fid); fid = NULL; P9_DPRINTK(P9_DEBUG_ERROR, "cannot attach\n"); goto error; } return fid; error: v9fs_session_close(v9ses); return ERR_PTR(retval); } /** * v9fs_session_close - shutdown a session * @v9ses: session information structure * */ void v9fs_session_close(struct v9fs_session_info *v9ses) { if (v9ses->clnt) { p9_client_destroy(v9ses->clnt); v9ses->clnt = NULL; } __putname(v9ses->name); __putname(v9ses->remotename); kfree(v9ses->options); } /** * v9fs_session_cancel - mark transport as disconnected * and cancel all pending requests. */ void v9fs_session_cancel(struct v9fs_session_info *v9ses) { P9_DPRINTK(P9_DEBUG_ERROR, "cancel session %p\n", v9ses); p9_client_disconnect(v9ses->clnt); } extern int v9fs_error_init(void); /** * v9fs_init - Initialize module * */ static int __init init_v9fs(void) { printk(KERN_INFO "Installing v9fs 9p2000 file system support\n"); /* TODO: Setup list of registered trasnport modules */ return register_filesystem(&v9fs_fs_type); } /** * v9fs_init - shutdown module * */ static void __exit exit_v9fs(void) { unregister_filesystem(&v9fs_fs_type); } module_init(init_v9fs) module_exit(exit_v9fs) MODULE_AUTHOR("Latchesar Ionkov "); MODULE_AUTHOR("Eric Van Hensbergen "); MODULE_AUTHOR("Ron Minnich "); MODULE_LICENSE("GPL");