/* * linux/fs/9p/vfs_super.c * * This file contians superblock ops for 9P2000. It is intended that * you mount this file system on directories. * * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com> * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov> * * 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 <linux/kernel.h> #include <linux/module.h> #include <linux/errno.h> #include <linux/fs.h> #include <linux/file.h> #include <linux/stat.h> #include <linux/string.h> #include <linux/inet.h> #include <linux/pagemap.h> #include <linux/seq_file.h> #include <linux/mount.h> #include <linux/idr.h> #include <linux/sched.h> #include <net/9p/9p.h> #include <net/9p/client.h> #include "v9fs.h" #include "v9fs_vfs.h" #include "fid.h" static void v9fs_clear_inode(struct inode *); static const struct super_operations v9fs_super_ops; /** * v9fs_clear_inode - release an inode * @inode: inode to release * */ static void v9fs_clear_inode(struct inode *inode) { filemap_fdatawrite(inode->i_mapping); } /** * v9fs_set_super - set the superblock * @s: super block * @data: file system specific data * */ static int v9fs_set_super(struct super_block *s, void *data) { s->s_fs_info = data; return set_anon_super(s, data); } /** * v9fs_fill_super - populate superblock with info * @sb: superblock * @v9ses: session information * */ static void v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses, int flags) { sb->s_maxbytes = MAX_LFS_FILESIZE; sb->s_blocksize_bits = fls(v9ses->maxdata - 1); sb->s_blocksize = 1 << sb->s_blocksize_bits; sb->s_magic = V9FS_MAGIC; sb->s_op = &v9fs_super_ops; sb->s_flags = flags | MS_ACTIVE | MS_SYNCHRONOUS | MS_DIRSYNC | MS_NOATIME; } /** * v9fs_get_sb - mount a superblock * @fs_type: file system type * @flags: mount flags * @dev_name: device name that was mounted * @data: mount options * @mnt: mountpoint record to be instantiated * */ static int v9fs_get_sb(struct file_system_type *fs_type, int flags, const char *dev_name, void *data, struct vfsmount *mnt) { struct super_block *sb = NULL; struct inode *inode = NULL; struct dentry *root = NULL; struct v9fs_session_info *v9ses = NULL; struct p9_stat *st = NULL; int mode = S_IRWXUGO | S_ISVTX; uid_t uid = current->fsuid; gid_t gid = current->fsgid; struct p9_fid *fid; int retval = 0; P9_DPRINTK(P9_DEBUG_VFS, " \n"); st = NULL; v9ses = kzalloc(sizeof(struct v9fs_session_info), GFP_KERNEL); if (!v9ses) return -ENOMEM; fid = v9fs_session_init(v9ses, dev_name, data); if (IS_ERR(fid)) { retval = PTR_ERR(fid); fid = NULL; kfree(v9ses); v9ses = NULL; goto error; } st = p9_client_stat(fid); if (IS_ERR(st)) { retval = PTR_ERR(st); goto error; } sb = sget(fs_type, NULL, v9fs_set_super, v9ses); if (IS_ERR(sb)) { retval = PTR_ERR(sb); goto error; } v9fs_fill_super(sb, v9ses, flags); inode = v9fs_get_inode(sb, S_IFDIR | mode); if (IS_ERR(inode)) { retval = PTR_ERR(inode); goto error; } inode->i_uid = uid; inode->i_gid = gid; root = d_alloc_root(inode); if (!root) { retval = -ENOMEM; goto error; } sb->s_root = root; root->d_inode->i_ino = v9fs_qid2ino(&st->qid); v9fs_stat2inode(st, root->d_inode, sb); v9fs_fid_add(root, fid); kfree(st); return simple_set_mnt(mnt, sb); error: kfree(st); if (fid) p9_client_clunk(fid); if (v9ses) { v9fs_session_close(v9ses); kfree(v9ses); } if (sb) { up_write(&sb->s_umount); deactivate_super(sb); } return retval; } /** * v9fs_kill_super - Kill Superblock * @s: superblock * */ static void v9fs_kill_super(struct super_block *s) { struct v9fs_session_info *v9ses = s->s_fs_info; P9_DPRINTK(P9_DEBUG_VFS, " %p\n", s); v9fs_dentry_release(s->s_root); /* clunk root */ kill_anon_super(s); v9fs_session_close(v9ses); kfree(v9ses); P9_DPRINTK(P9_DEBUG_VFS, "exiting kill_super\n"); } /** * v9fs_show_options - Show mount options in /proc/mounts * @m: seq_file to write to * @mnt: mount descriptor * */ static int v9fs_show_options(struct seq_file *m, struct vfsmount *mnt) { struct v9fs_session_info *v9ses = mnt->mnt_sb->s_fs_info; seq_printf(m, "%s", v9ses->options); return 0; } static void v9fs_umount_begin(struct vfsmount *vfsmnt, int flags) { struct v9fs_session_info *v9ses = vfsmnt->mnt_sb->s_fs_info; if (flags & MNT_FORCE) v9fs_session_cancel(v9ses); } static const struct super_operations v9fs_super_ops = { .statfs = simple_statfs, .clear_inode = v9fs_clear_inode, .show_options = v9fs_show_options, .umount_begin = v9fs_umount_begin, }; struct file_system_type v9fs_fs_type = { .name = "9p", .get_sb = v9fs_get_sb, .kill_sb = v9fs_kill_super, .owner = THIS_MODULE, };