diff options
Diffstat (limited to 'fs/autofs/inode.c')
-rw-r--r-- | fs/autofs/inode.c | 371 |
1 files changed, 371 insertions, 0 deletions
diff --git a/fs/autofs/inode.c b/fs/autofs/inode.c new file mode 100644 index 000000000000..b51980fc274e --- /dev/null +++ b/fs/autofs/inode.c @@ -0,0 +1,371 @@ +/* + * Copyright 1997-1998 Transmeta Corporation -- All Rights Reserved + * Copyright 2005-2006 Ian Kent <raven@themaw.net> + * + * This file is part of the Linux kernel and is made available under + * the terms of the GNU General Public License, version 2, or at your + * option, any later version, incorporated herein by reference. + */ + +#include <linux/seq_file.h> +#include <linux/pagemap.h> +#include <linux/parser.h> +#include <linux/magic.h> + +#include "autofs_i.h" + +struct autofs_info *autofs_new_ino(struct autofs_sb_info *sbi) +{ + struct autofs_info *ino; + + ino = kzalloc(sizeof(*ino), GFP_KERNEL); + if (ino) { + INIT_LIST_HEAD(&ino->active); + INIT_LIST_HEAD(&ino->expiring); + ino->last_used = jiffies; + ino->sbi = sbi; + } + return ino; +} + +void autofs_clean_ino(struct autofs_info *ino) +{ + ino->uid = GLOBAL_ROOT_UID; + ino->gid = GLOBAL_ROOT_GID; + ino->last_used = jiffies; +} + +void autofs_free_ino(struct autofs_info *ino) +{ + kfree(ino); +} + +void autofs_kill_sb(struct super_block *sb) +{ + struct autofs_sb_info *sbi = autofs_sbi(sb); + + /* + * In the event of a failure in get_sb_nodev the superblock + * info is not present so nothing else has been setup, so + * just call kill_anon_super when we are called from + * deactivate_super. + */ + if (sbi) { + /* Free wait queues, close pipe */ + autofs_catatonic_mode(sbi); + put_pid(sbi->oz_pgrp); + } + + pr_debug("shutting down\n"); + kill_litter_super(sb); + if (sbi) + kfree_rcu(sbi, rcu); +} + +static int autofs_show_options(struct seq_file *m, struct dentry *root) +{ + struct autofs_sb_info *sbi = autofs_sbi(root->d_sb); + struct inode *root_inode = d_inode(root->d_sb->s_root); + + if (!sbi) + return 0; + + seq_printf(m, ",fd=%d", sbi->pipefd); + if (!uid_eq(root_inode->i_uid, GLOBAL_ROOT_UID)) + seq_printf(m, ",uid=%u", + from_kuid_munged(&init_user_ns, root_inode->i_uid)); + if (!gid_eq(root_inode->i_gid, GLOBAL_ROOT_GID)) + seq_printf(m, ",gid=%u", + from_kgid_munged(&init_user_ns, root_inode->i_gid)); + seq_printf(m, ",pgrp=%d", pid_vnr(sbi->oz_pgrp)); + seq_printf(m, ",timeout=%lu", sbi->exp_timeout/HZ); + seq_printf(m, ",minproto=%d", sbi->min_proto); + seq_printf(m, ",maxproto=%d", sbi->max_proto); + + if (autofs_type_offset(sbi->type)) + seq_printf(m, ",offset"); + else if (autofs_type_direct(sbi->type)) + seq_printf(m, ",direct"); + else + seq_printf(m, ",indirect"); +#ifdef CONFIG_CHECKPOINT_RESTORE + if (sbi->pipe) + seq_printf(m, ",pipe_ino=%ld", file_inode(sbi->pipe)->i_ino); + else + seq_printf(m, ",pipe_ino=-1"); +#endif + return 0; +} + +static void autofs_evict_inode(struct inode *inode) +{ + clear_inode(inode); + kfree(inode->i_private); +} + +static const struct super_operations autofs_sops = { + .statfs = simple_statfs, + .show_options = autofs_show_options, + .evict_inode = autofs_evict_inode, +}; + +enum {Opt_err, Opt_fd, Opt_uid, Opt_gid, Opt_pgrp, Opt_minproto, Opt_maxproto, + Opt_indirect, Opt_direct, Opt_offset}; + +static const match_table_t tokens = { + {Opt_fd, "fd=%u"}, + {Opt_uid, "uid=%u"}, + {Opt_gid, "gid=%u"}, + {Opt_pgrp, "pgrp=%u"}, + {Opt_minproto, "minproto=%u"}, + {Opt_maxproto, "maxproto=%u"}, + {Opt_indirect, "indirect"}, + {Opt_direct, "direct"}, + {Opt_offset, "offset"}, + {Opt_err, NULL} +}; + +static int parse_options(char *options, int *pipefd, kuid_t *uid, kgid_t *gid, + int *pgrp, bool *pgrp_set, unsigned int *type, + int *minproto, int *maxproto) +{ + char *p; + substring_t args[MAX_OPT_ARGS]; + int option; + + *uid = current_uid(); + *gid = current_gid(); + + *minproto = AUTOFS_MIN_PROTO_VERSION; + *maxproto = AUTOFS_MAX_PROTO_VERSION; + + *pipefd = -1; + + if (!options) + return 1; + + while ((p = strsep(&options, ",")) != NULL) { + int token; + + if (!*p) + continue; + + token = match_token(p, tokens, args); + switch (token) { + case Opt_fd: + if (match_int(args, pipefd)) + return 1; + break; + case Opt_uid: + if (match_int(args, &option)) + return 1; + *uid = make_kuid(current_user_ns(), option); + if (!uid_valid(*uid)) + return 1; + break; + case Opt_gid: + if (match_int(args, &option)) + return 1; + *gid = make_kgid(current_user_ns(), option); + if (!gid_valid(*gid)) + return 1; + break; + case Opt_pgrp: + if (match_int(args, &option)) + return 1; + *pgrp = option; + *pgrp_set = true; + break; + case Opt_minproto: + if (match_int(args, &option)) + return 1; + *minproto = option; + break; + case Opt_maxproto: + if (match_int(args, &option)) + return 1; + *maxproto = option; + break; + case Opt_indirect: + set_autofs_type_indirect(type); + break; + case Opt_direct: + set_autofs_type_direct(type); + break; + case Opt_offset: + set_autofs_type_offset(type); + break; + default: + return 1; + } + } + return (*pipefd < 0); +} + +int autofs_fill_super(struct super_block *s, void *data, int silent) +{ + struct inode *root_inode; + struct dentry *root; + struct file *pipe; + int pipefd; + struct autofs_sb_info *sbi; + struct autofs_info *ino; + int pgrp = 0; + bool pgrp_set = false; + int ret = -EINVAL; + + sbi = kzalloc(sizeof(*sbi), GFP_KERNEL); + if (!sbi) + return -ENOMEM; + pr_debug("starting up, sbi = %p\n", sbi); + + s->s_fs_info = sbi; + sbi->magic = AUTOFS_SBI_MAGIC; + sbi->pipefd = -1; + sbi->pipe = NULL; + sbi->catatonic = 1; + sbi->exp_timeout = 0; + sbi->oz_pgrp = NULL; + sbi->sb = s; + sbi->version = 0; + sbi->sub_version = 0; + set_autofs_type_indirect(&sbi->type); + sbi->min_proto = 0; + sbi->max_proto = 0; + mutex_init(&sbi->wq_mutex); + mutex_init(&sbi->pipe_mutex); + spin_lock_init(&sbi->fs_lock); + sbi->queues = NULL; + spin_lock_init(&sbi->lookup_lock); + INIT_LIST_HEAD(&sbi->active_list); + INIT_LIST_HEAD(&sbi->expiring_list); + s->s_blocksize = 1024; + s->s_blocksize_bits = 10; + s->s_magic = AUTOFS_SUPER_MAGIC; + s->s_op = &autofs_sops; + s->s_d_op = &autofs_dentry_operations; + s->s_time_gran = 1; + + /* + * Get the root inode and dentry, but defer checking for errors. + */ + ino = autofs_new_ino(sbi); + if (!ino) { + ret = -ENOMEM; + goto fail_free; + } + root_inode = autofs_get_inode(s, S_IFDIR | 0755); + root = d_make_root(root_inode); + if (!root) + goto fail_ino; + pipe = NULL; + + root->d_fsdata = ino; + + /* Can this call block? */ + if (parse_options(data, &pipefd, &root_inode->i_uid, &root_inode->i_gid, + &pgrp, &pgrp_set, &sbi->type, &sbi->min_proto, + &sbi->max_proto)) { + pr_err("called with bogus options\n"); + goto fail_dput; + } + + /* Test versions first */ + if (sbi->max_proto < AUTOFS_MIN_PROTO_VERSION || + sbi->min_proto > AUTOFS_MAX_PROTO_VERSION) { + pr_err("kernel does not match daemon version " + "daemon (%d, %d) kernel (%d, %d)\n", + sbi->min_proto, sbi->max_proto, + AUTOFS_MIN_PROTO_VERSION, AUTOFS_MAX_PROTO_VERSION); + goto fail_dput; + } + + /* Establish highest kernel protocol version */ + if (sbi->max_proto > AUTOFS_MAX_PROTO_VERSION) + sbi->version = AUTOFS_MAX_PROTO_VERSION; + else + sbi->version = sbi->max_proto; + sbi->sub_version = AUTOFS_PROTO_SUBVERSION; + + if (pgrp_set) { + sbi->oz_pgrp = find_get_pid(pgrp); + if (!sbi->oz_pgrp) { + pr_err("could not find process group %d\n", + pgrp); + goto fail_dput; + } + } else { + sbi->oz_pgrp = get_task_pid(current, PIDTYPE_PGID); + } + + if (autofs_type_trigger(sbi->type)) + __managed_dentry_set_managed(root); + + root_inode->i_fop = &autofs_root_operations; + root_inode->i_op = &autofs_dir_inode_operations; + + pr_debug("pipe fd = %d, pgrp = %u\n", pipefd, pid_nr(sbi->oz_pgrp)); + pipe = fget(pipefd); + + if (!pipe) { + pr_err("could not open pipe file descriptor\n"); + goto fail_put_pid; + } + ret = autofs_prepare_pipe(pipe); + if (ret < 0) + goto fail_fput; + sbi->pipe = pipe; + sbi->pipefd = pipefd; + sbi->catatonic = 0; + + /* + * Success! Install the root dentry now to indicate completion. + */ + s->s_root = root; + return 0; + + /* + * Failure ... clean up. + */ +fail_fput: + pr_err("pipe file descriptor does not contain proper ops\n"); + fput(pipe); +fail_put_pid: + put_pid(sbi->oz_pgrp); +fail_dput: + dput(root); + goto fail_free; +fail_ino: + autofs_free_ino(ino); +fail_free: + kfree(sbi); + s->s_fs_info = NULL; + return ret; +} + +struct inode *autofs_get_inode(struct super_block *sb, umode_t mode) +{ + struct inode *inode = new_inode(sb); + + if (inode == NULL) + return NULL; + + inode->i_mode = mode; + if (sb->s_root) { + inode->i_uid = d_inode(sb->s_root)->i_uid; + inode->i_gid = d_inode(sb->s_root)->i_gid; + } + inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode); + inode->i_ino = get_next_ino(); + + if (S_ISDIR(mode)) { + set_nlink(inode, 2); + inode->i_op = &autofs_dir_inode_operations; + inode->i_fop = &autofs_dir_operations; + } else if (S_ISLNK(mode)) { + inode->i_op = &autofs_symlink_inode_operations; + } else + WARN_ON(1); + + return inode; +} |