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Diffstat (limited to 'net/9p/mod.c')
| -rw-r--r-- | net/9p/mod.c | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/net/9p/mod.c b/net/9p/mod.c new file mode 100644 index 000000000..55576c186 --- /dev/null +++ b/net/9p/mod.c @@ -0,0 +1,212 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * 9P entry point + * + * Copyright (C) 2007 by Latchesar Ionkov <lucho@ionkov.net> + * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com> + * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov> + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/kmod.h> +#include <linux/errno.h> +#include <linux/sched.h> +#include <linux/moduleparam.h> +#include <net/9p/9p.h> +#include <linux/fs.h> +#include <linux/parser.h> +#include <net/9p/client.h> +#include <net/9p/transport.h> +#include <linux/list.h> +#include <linux/spinlock.h> + +#ifdef CONFIG_NET_9P_DEBUG +unsigned int p9_debug_level; /* feature-rific global debug level */ +EXPORT_SYMBOL(p9_debug_level); +module_param_named(debug, p9_debug_level, uint, 0); +MODULE_PARM_DESC(debug, "9P debugging level"); + +void _p9_debug(enum p9_debug_flags level, const char *func, + const char *fmt, ...) +{ + struct va_format vaf; + va_list args; + + if ((p9_debug_level & level) != level) + return; + + va_start(args, fmt); + + vaf.fmt = fmt; + vaf.va = &args; + + if (level == P9_DEBUG_9P) + pr_notice("(%8.8d) %pV", task_pid_nr(current), &vaf); + else + pr_notice("-- %s (%d): %pV", func, task_pid_nr(current), &vaf); + + va_end(args); +} +EXPORT_SYMBOL(_p9_debug); +#endif + +/* Dynamic Transport Registration Routines */ + +static DEFINE_SPINLOCK(v9fs_trans_lock); +static LIST_HEAD(v9fs_trans_list); + +/** + * 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) +{ + spin_lock(&v9fs_trans_lock); + list_add_tail(&m->list, &v9fs_trans_list); + spin_unlock(&v9fs_trans_lock); +} +EXPORT_SYMBOL(v9fs_register_trans); + +/** + * v9fs_unregister_trans - unregister a 9p transport + * @m: the transport to remove + * + */ +void v9fs_unregister_trans(struct p9_trans_module *m) +{ + spin_lock(&v9fs_trans_lock); + list_del_init(&m->list); + spin_unlock(&v9fs_trans_lock); +} +EXPORT_SYMBOL(v9fs_unregister_trans); + +static struct p9_trans_module *_p9_get_trans_by_name(const char *s) +{ + struct p9_trans_module *t, *found = NULL; + + spin_lock(&v9fs_trans_lock); + + list_for_each_entry(t, &v9fs_trans_list, list) + if (strcmp(t->name, s) == 0 && + try_module_get(t->owner)) { + found = t; + break; + } + + spin_unlock(&v9fs_trans_lock); + + return found; +} + +/** + * v9fs_get_trans_by_name - get transport with the matching name + * @s: string identifying transport + * + */ +struct p9_trans_module *v9fs_get_trans_by_name(const char *s) +{ + struct p9_trans_module *found = NULL; + + found = _p9_get_trans_by_name(s); + +#ifdef CONFIG_MODULES + if (!found) { + request_module("9p-%s", s); + found = _p9_get_trans_by_name(s); + } +#endif + + return found; +} +EXPORT_SYMBOL(v9fs_get_trans_by_name); + +static const char * const v9fs_default_transports[] = { + "virtio", "tcp", "fd", "unix", "xen", "rdma", +}; + +/** + * v9fs_get_default_trans - get the default transport + * + */ + +struct p9_trans_module *v9fs_get_default_trans(void) +{ + struct p9_trans_module *t, *found = NULL; + int i; + + spin_lock(&v9fs_trans_lock); + + list_for_each_entry(t, &v9fs_trans_list, list) + if (t->def && try_module_get(t->owner)) { + found = t; + break; + } + + if (!found) + list_for_each_entry(t, &v9fs_trans_list, list) + if (try_module_get(t->owner)) { + found = t; + break; + } + + spin_unlock(&v9fs_trans_lock); + + for (i = 0; !found && i < ARRAY_SIZE(v9fs_default_transports); i++) + found = v9fs_get_trans_by_name(v9fs_default_transports[i]); + + return found; +} +EXPORT_SYMBOL(v9fs_get_default_trans); + +/** + * v9fs_put_trans - put trans + * @m: transport to put + * + */ +void v9fs_put_trans(struct p9_trans_module *m) +{ + if (m) + module_put(m->owner); +} + +/** + * init_p9 - Initialize module + * + */ +static int __init init_p9(void) +{ + int ret; + + ret = p9_client_init(); + if (ret) + return ret; + + p9_error_init(); + pr_info("Installing 9P2000 support\n"); + + return ret; +} + +/** + * exit_p9 - shutdown module + * + */ + +static void __exit exit_p9(void) +{ + pr_info("Unloading 9P2000 support\n"); + + p9_client_exit(); +} + +module_init(init_p9) +module_exit(exit_p9) + +MODULE_AUTHOR("Latchesar Ionkov <lucho@ionkov.net>"); +MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>"); +MODULE_AUTHOR("Ron Minnich <rminnich@lanl.gov>"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Plan 9 Resource Sharing Support (9P2000)"); |