diff options
Diffstat (limited to 'fs/9p/v9fs.c')
| -rw-r--r-- | fs/9p/v9fs.c | 520 |
1 files changed, 454 insertions, 66 deletions
diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c index 9b0f0222e8b..6894b085f0e 100644 --- a/fs/9p/v9fs.c +++ b/fs/9p/v9fs.c @@ -23,39 +23,47 @@ * */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + #include <linux/module.h> #include <linux/errno.h> #include <linux/fs.h> #include <linux/sched.h> #include <linux/parser.h> #include <linux/idr.h> +#include <linux/slab.h> #include <net/9p/9p.h> -#include <net/9p/transport.h> #include <net/9p/client.h> +#include <net/9p/transport.h> #include "v9fs.h" #include "v9fs_vfs.h" +#include "cache.h" + +static DEFINE_SPINLOCK(v9fs_sessionlist_lock); +static LIST_HEAD(v9fs_sessionlist); +struct kmem_cache *v9fs_inode_cache; /* - * Option Parsing (code inspired by NFS code) - * NOTE: each transport will parse its own options - */ + * Option Parsing (code inspired by NFS code) + * NOTE: each transport will parse its own options + */ enum { /* Options that take integer arguments */ Opt_debug, Opt_dfltuid, Opt_dfltgid, Opt_afid, /* String options */ - Opt_uname, Opt_remotename, Opt_trans, + Opt_uname, Opt_remotename, Opt_trans, Opt_cache, Opt_cachetag, /* Options that take no arguments */ Opt_nodevmap, /* Cache options */ - Opt_cache_loose, + Opt_cache_loose, Opt_fscache, Opt_mmap, /* Access options */ - Opt_access, + Opt_access, Opt_posixacl, /* Error token */ Opt_err }; -static match_table_t tokens = { +static const match_table_t tokens = { {Opt_debug, "debug=%x"}, {Opt_dfltuid, "dfltuid=%u"}, {Opt_dfltgid, "dfltgid=%u"}, @@ -63,52 +71,86 @@ static match_table_t tokens = { {Opt_uname, "uname=%s"}, {Opt_remotename, "aname=%s"}, {Opt_nodevmap, "nodevmap"}, - {Opt_cache_loose, "cache=loose"}, + {Opt_cache, "cache=%s"}, {Opt_cache_loose, "loose"}, + {Opt_fscache, "fscache"}, + {Opt_mmap, "mmap"}, + {Opt_cachetag, "cachetag=%s"}, {Opt_access, "access=%s"}, + {Opt_posixacl, "posixacl"}, {Opt_err, NULL} }; +/* Interpret mount options for cache mode */ +static int get_cache_mode(char *s) +{ + int version = -EINVAL; + + if (!strcmp(s, "loose")) { + version = CACHE_LOOSE; + p9_debug(P9_DEBUG_9P, "Cache mode: loose\n"); + } else if (!strcmp(s, "fscache")) { + version = CACHE_FSCACHE; + p9_debug(P9_DEBUG_9P, "Cache mode: fscache\n"); + } else if (!strcmp(s, "mmap")) { + version = CACHE_MMAP; + p9_debug(P9_DEBUG_9P, "Cache mode: mmap\n"); + } else if (!strcmp(s, "none")) { + version = CACHE_NONE; + p9_debug(P9_DEBUG_9P, "Cache mode: none\n"); + } else + pr_info("Unknown Cache mode %s\n", s); + return version; +} + /** * v9fs_parse_options - parse mount options into session structure - * @options: options string passed from mount * @v9ses: existing v9fs session information * + * Return 0 upon success, -ERRNO upon failure. */ -static void v9fs_parse_options(struct v9fs_session_info *v9ses) +static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts) { - char *options; + char *options, *tmp_options; substring_t args[MAX_OPT_ARGS]; char *p; int option = 0; char *s, *e; - int ret; + int ret = 0; /* setup defaults */ v9ses->afid = ~0; v9ses->debug = 0; - v9ses->cache = 0; + v9ses->cache = CACHE_NONE; +#ifdef CONFIG_9P_FSCACHE + v9ses->cachetag = NULL; +#endif + + if (!opts) + return 0; - if (!v9ses->options) - return; + tmp_options = kstrdup(opts, GFP_KERNEL); + if (!tmp_options) { + ret = -ENOMEM; + goto fail_option_alloc; + } + options = tmp_options; - options = kstrdup(v9ses->options, GFP_KERNEL); while ((p = strsep(&options, ",")) != NULL) { - int token; + int token, r; if (!*p) continue; token = match_token(p, tokens, args); - if (token < Opt_uname) { - ret = match_int(&args[0], &option); - if (ret < 0) { - P9_DPRINTK(P9_DEBUG_ERROR, - "integer field, but no integer?\n"); - continue; - } - } switch (token) { case Opt_debug: + r = match_int(&args[0], &option); + if (r < 0) { + p9_debug(P9_DEBUG_ERROR, + "integer field, but no integer?\n"); + ret = r; + continue; + } v9ses->debug = option; #ifdef CONFIG_NET_9P_DEBUG p9_debug_level = option; @@ -116,19 +158,62 @@ static void v9fs_parse_options(struct v9fs_session_info *v9ses) break; case Opt_dfltuid: - v9ses->dfltuid = option; + r = match_int(&args[0], &option); + if (r < 0) { + p9_debug(P9_DEBUG_ERROR, + "integer field, but no integer?\n"); + ret = r; + continue; + } + v9ses->dfltuid = make_kuid(current_user_ns(), option); + if (!uid_valid(v9ses->dfltuid)) { + p9_debug(P9_DEBUG_ERROR, + "uid field, but not a uid?\n"); + ret = -EINVAL; + continue; + } break; case Opt_dfltgid: - v9ses->dfltgid = option; + r = match_int(&args[0], &option); + if (r < 0) { + p9_debug(P9_DEBUG_ERROR, + "integer field, but no integer?\n"); + ret = r; + continue; + } + v9ses->dfltgid = make_kgid(current_user_ns(), option); + if (!gid_valid(v9ses->dfltgid)) { + p9_debug(P9_DEBUG_ERROR, + "gid field, but not a gid?\n"); + ret = -EINVAL; + continue; + } break; case Opt_afid: + r = match_int(&args[0], &option); + if (r < 0) { + p9_debug(P9_DEBUG_ERROR, + "integer field, but no integer?\n"); + ret = r; + continue; + } v9ses->afid = option; break; case Opt_uname: - match_strcpy(v9ses->uname, &args[0]); + kfree(v9ses->uname); + v9ses->uname = match_strdup(&args[0]); + if (!v9ses->uname) { + ret = -ENOMEM; + goto free_and_return; + } break; case Opt_remotename: - match_strcpy(v9ses->aname, &args[0]); + kfree(v9ses->aname); + v9ses->aname = match_strdup(&args[0]); + if (!v9ses->aname) { + ret = -ENOMEM; + goto free_and_return; + } break; case Opt_nodevmap: v9ses->nodev = 1; @@ -136,28 +221,92 @@ static void v9fs_parse_options(struct v9fs_session_info *v9ses) case Opt_cache_loose: v9ses->cache = CACHE_LOOSE; break; + case Opt_fscache: + v9ses->cache = CACHE_FSCACHE; + break; + case Opt_mmap: + v9ses->cache = CACHE_MMAP; + break; + case Opt_cachetag: +#ifdef CONFIG_9P_FSCACHE + v9ses->cachetag = match_strdup(&args[0]); +#endif + break; + case Opt_cache: + s = match_strdup(&args[0]); + if (!s) { + ret = -ENOMEM; + p9_debug(P9_DEBUG_ERROR, + "problem allocating copy of cache arg\n"); + goto free_and_return; + } + ret = get_cache_mode(s); + if (ret == -EINVAL) { + kfree(s); + goto free_and_return; + } + + v9ses->cache = ret; + kfree(s); + break; case Opt_access: s = match_strdup(&args[0]); + if (!s) { + ret = -ENOMEM; + p9_debug(P9_DEBUG_ERROR, + "problem allocating copy of access arg\n"); + goto free_and_return; + } + v9ses->flags &= ~V9FS_ACCESS_MASK; if (strcmp(s, "user") == 0) v9ses->flags |= V9FS_ACCESS_USER; else if (strcmp(s, "any") == 0) v9ses->flags |= V9FS_ACCESS_ANY; - else { + else if (strcmp(s, "client") == 0) { + v9ses->flags |= V9FS_ACCESS_CLIENT; + } else { + uid_t uid; v9ses->flags |= V9FS_ACCESS_SINGLE; - v9ses->uid = simple_strtol(s, &e, 10); - if (*e != '\0') - v9ses->uid = ~0; + uid = simple_strtoul(s, &e, 10); + if (*e != '\0') { + ret = -EINVAL; + pr_info("Unknown access argument %s\n", + s); + kfree(s); + goto free_and_return; + } + v9ses->uid = make_kuid(current_user_ns(), uid); + if (!uid_valid(v9ses->uid)) { + ret = -EINVAL; + pr_info("Uknown uid %s\n", s); + kfree(s); + goto free_and_return; + } } + kfree(s); break; + case Opt_posixacl: +#ifdef CONFIG_9P_FS_POSIX_ACL + v9ses->flags |= V9FS_POSIX_ACL; +#else + p9_debug(P9_DEBUG_ERROR, + "Not defined CONFIG_9P_FS_POSIX_ACL. Ignoring posixacl option\n"); +#endif + break; + default: continue; } } - kfree(options); + +free_and_return: + kfree(tmp_options); +fail_option_alloc: + return ret; } /** @@ -173,67 +322,109 @@ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses, { int retval = -EINVAL; struct p9_fid *fid; + int rc; - v9ses->uname = __getname(); + v9ses->uname = kstrdup(V9FS_DEFUSER, GFP_KERNEL); if (!v9ses->uname) return ERR_PTR(-ENOMEM); - v9ses->aname = __getname(); + v9ses->aname = kstrdup(V9FS_DEFANAME, GFP_KERNEL); if (!v9ses->aname) { - __putname(v9ses->uname); + kfree(v9ses->uname); return ERR_PTR(-ENOMEM); } + init_rwsem(&v9ses->rename_sem); + + rc = bdi_setup_and_register(&v9ses->bdi, "9p", BDI_CAP_MAP_COPY); + if (rc) { + kfree(v9ses->aname); + kfree(v9ses->uname); + return ERR_PTR(rc); + } - v9ses->flags = V9FS_EXTENDED | V9FS_ACCESS_USER; - strcpy(v9ses->uname, V9FS_DEFUSER); - strcpy(v9ses->aname, V9FS_DEFANAME); - v9ses->uid = ~0; + spin_lock(&v9fs_sessionlist_lock); + list_add(&v9ses->slist, &v9fs_sessionlist); + spin_unlock(&v9fs_sessionlist_lock); + + v9ses->uid = INVALID_UID; v9ses->dfltuid = V9FS_DEFUID; v9ses->dfltgid = V9FS_DEFGID; - v9ses->options = kstrdup(data, GFP_KERNEL); - v9fs_parse_options(v9ses); - - v9ses->clnt = p9_client_create(dev_name, v9ses->options); + v9ses->clnt = p9_client_create(dev_name, data); if (IS_ERR(v9ses->clnt)) { retval = PTR_ERR(v9ses->clnt); v9ses->clnt = NULL; - P9_DPRINTK(P9_DEBUG_ERROR, "problem initializing 9p client\n"); + p9_debug(P9_DEBUG_ERROR, "problem initializing 9p client\n"); goto error; } - if (!v9ses->clnt->dotu) - v9ses->flags &= ~V9FS_EXTENDED; + v9ses->flags = V9FS_ACCESS_USER; - v9ses->maxdata = v9ses->clnt->msize; + if (p9_is_proto_dotl(v9ses->clnt)) { + v9ses->flags = V9FS_ACCESS_CLIENT; + v9ses->flags |= V9FS_PROTO_2000L; + } else if (p9_is_proto_dotu(v9ses->clnt)) { + v9ses->flags |= V9FS_PROTO_2000U; + } + + rc = v9fs_parse_options(v9ses, data); + if (rc < 0) { + retval = rc; + goto error; + } + v9ses->maxdata = v9ses->clnt->msize - P9_IOHDRSZ; + + if (!v9fs_proto_dotl(v9ses) && + ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) { + /* + * We support ACCESS_CLIENT only for dotl. + * Fall back to ACCESS_USER + */ + v9ses->flags &= ~V9FS_ACCESS_MASK; + v9ses->flags |= V9FS_ACCESS_USER; + } + /*FIXME !! */ /* for legacy mode, fall back to V9FS_ACCESS_ANY */ - if (!v9fs_extended(v9ses) && + if (!(v9fs_proto_dotu(v9ses) || v9fs_proto_dotl(v9ses)) && ((v9ses->flags&V9FS_ACCESS_MASK) == V9FS_ACCESS_USER)) { v9ses->flags &= ~V9FS_ACCESS_MASK; v9ses->flags |= V9FS_ACCESS_ANY; - v9ses->uid = ~0; + v9ses->uid = INVALID_UID; + } + if (!v9fs_proto_dotl(v9ses) || + !((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) { + /* + * We support ACL checks on clinet only if the protocol is + * 9P2000.L and access is V9FS_ACCESS_CLIENT. + */ + v9ses->flags &= ~V9FS_ACL_MASK; } - fid = p9_client_attach(v9ses->clnt, NULL, v9ses->uname, ~0, + fid = p9_client_attach(v9ses->clnt, NULL, v9ses->uname, INVALID_UID, v9ses->aname); if (IS_ERR(fid)) { retval = PTR_ERR(fid); fid = NULL; - P9_DPRINTK(P9_DEBUG_ERROR, "cannot attach\n"); + p9_debug(P9_DEBUG_ERROR, "cannot attach\n"); goto error; } if ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_SINGLE) fid->uid = v9ses->uid; else - fid->uid = ~0; + fid->uid = INVALID_UID; + +#ifdef CONFIG_9P_FSCACHE + /* register the session for caching */ + v9fs_cache_session_get_cookie(v9ses); +#endif return fid; error: - v9fs_session_close(v9ses); + bdi_destroy(&v9ses->bdi); return ERR_PTR(retval); } @@ -250,41 +441,238 @@ void v9fs_session_close(struct v9fs_session_info *v9ses) v9ses->clnt = NULL; } - __putname(v9ses->uname); - __putname(v9ses->aname); - kfree(v9ses->options); +#ifdef CONFIG_9P_FSCACHE + if (v9ses->fscache) { + v9fs_cache_session_put_cookie(v9ses); + kfree(v9ses->cachetag); + } +#endif + kfree(v9ses->uname); + kfree(v9ses->aname); + + bdi_destroy(&v9ses->bdi); + + spin_lock(&v9fs_sessionlist_lock); + list_del(&v9ses->slist); + spin_unlock(&v9fs_sessionlist_lock); } /** - * v9fs_session_cancel - mark transport as disconnected - * and cancel all pending requests. + * v9fs_session_cancel - terminate a session + * @v9ses: session to terminate + * + * 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_debug(P9_DEBUG_ERROR, "cancel session %p\n", v9ses); p9_client_disconnect(v9ses->clnt); } +/** + * v9fs_session_begin_cancel - Begin terminate of a session + * @v9ses: session to terminate + * + * After this call we don't allow any request other than clunk. + */ + +void v9fs_session_begin_cancel(struct v9fs_session_info *v9ses) +{ + p9_debug(P9_DEBUG_ERROR, "begin cancel session %p\n", v9ses); + p9_client_begin_disconnect(v9ses->clnt); +} + extern int v9fs_error_init(void); +static struct kobject *v9fs_kobj; + +#ifdef CONFIG_9P_FSCACHE +/** + * caches_show - list caches associated with a session + * + * Returns the size of buffer written. + */ + +static ssize_t caches_show(struct kobject *kobj, + struct kobj_attribute *attr, + char *buf) +{ + ssize_t n = 0, count = 0, limit = PAGE_SIZE; + struct v9fs_session_info *v9ses; + + spin_lock(&v9fs_sessionlist_lock); + list_for_each_entry(v9ses, &v9fs_sessionlist, slist) { + if (v9ses->cachetag) { + n = snprintf(buf, limit, "%s\n", v9ses->cachetag); + if (n < 0) { + count = n; + break; + } + + count += n; + limit -= n; + } + } + + spin_unlock(&v9fs_sessionlist_lock); + return count; +} + +static struct kobj_attribute v9fs_attr_cache = __ATTR_RO(caches); +#endif /* CONFIG_9P_FSCACHE */ + +static struct attribute *v9fs_attrs[] = { +#ifdef CONFIG_9P_FSCACHE + &v9fs_attr_cache.attr, +#endif + NULL, +}; + +static struct attribute_group v9fs_attr_group = { + .attrs = v9fs_attrs, +}; + +/** + * v9fs_sysfs_init - Initialize the v9fs sysfs interface + * + */ + +static int __init v9fs_sysfs_init(void) +{ + v9fs_kobj = kobject_create_and_add("9p", fs_kobj); + if (!v9fs_kobj) + return -ENOMEM; + + if (sysfs_create_group(v9fs_kobj, &v9fs_attr_group)) { + kobject_put(v9fs_kobj); + return -ENOMEM; + } + + return 0; +} + /** - * v9fs_init - Initialize module + * v9fs_sysfs_cleanup - Unregister the v9fs sysfs interface + * + */ + +static void v9fs_sysfs_cleanup(void) +{ + sysfs_remove_group(v9fs_kobj, &v9fs_attr_group); + kobject_put(v9fs_kobj); +} + +static void v9fs_inode_init_once(void *foo) +{ + struct v9fs_inode *v9inode = (struct v9fs_inode *)foo; +#ifdef CONFIG_9P_FSCACHE + v9inode->fscache = NULL; +#endif + memset(&v9inode->qid, 0, sizeof(v9inode->qid)); + inode_init_once(&v9inode->vfs_inode); +} + +/** + * v9fs_init_inode_cache - initialize a cache for 9P + * Returns 0 on success. + */ +static int v9fs_init_inode_cache(void) +{ + v9fs_inode_cache = kmem_cache_create("v9fs_inode_cache", + sizeof(struct v9fs_inode), + 0, (SLAB_RECLAIM_ACCOUNT| + SLAB_MEM_SPREAD), + v9fs_inode_init_once); + if (!v9fs_inode_cache) + return -ENOMEM; + + return 0; +} + +/** + * v9fs_destroy_inode_cache - destroy the cache of 9P inode + * + */ +static void v9fs_destroy_inode_cache(void) +{ + /* + * Make sure all delayed rcu free inodes are flushed before we + * destroy cache. + */ + rcu_barrier(); + kmem_cache_destroy(v9fs_inode_cache); +} + +static int v9fs_cache_register(void) +{ + int ret; + ret = v9fs_init_inode_cache(); + if (ret < 0) + return ret; +#ifdef CONFIG_9P_FSCACHE + ret = fscache_register_netfs(&v9fs_cache_netfs); + if (ret < 0) + v9fs_destroy_inode_cache(); +#endif + return ret; +} + +static void v9fs_cache_unregister(void) +{ + v9fs_destroy_inode_cache(); +#ifdef CONFIG_9P_FSCACHE + fscache_unregister_netfs(&v9fs_cache_netfs); +#endif +} + +/** + * init_v9fs - Initialize module * */ static int __init init_v9fs(void) { - printk(KERN_INFO "Installing v9fs 9p2000 file system support\n"); + int err; + pr_info("Installing v9fs 9p2000 file system support\n"); /* TODO: Setup list of registered trasnport modules */ - return register_filesystem(&v9fs_fs_type); + + err = v9fs_cache_register(); + if (err < 0) { + pr_err("Failed to register v9fs for caching\n"); + return err; + } + + err = v9fs_sysfs_init(); + if (err < 0) { + pr_err("Failed to register with sysfs\n"); + goto out_cache; + } + err = register_filesystem(&v9fs_fs_type); + if (err < 0) { + pr_err("Failed to register filesystem\n"); + goto out_sysfs_cleanup; + } + + return 0; + +out_sysfs_cleanup: + v9fs_sysfs_cleanup(); + +out_cache: + v9fs_cache_unregister(); + + return err; } /** - * v9fs_init - shutdown module + * exit_v9fs - shutdown module * */ static void __exit exit_v9fs(void) { + v9fs_sysfs_cleanup(); + v9fs_cache_unregister(); unregister_filesystem(&v9fs_fs_type); } |