/* * 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 <linux/slab.h> #include <linux/statfs.h> #include <linux/magic.h> #include <net/9p/9p.h> #include <net/9p/client.h> #include "v9fs.h" #include "v9fs_vfs.h" #include "fid.h" #include "xattr.h" #include "acl.h" static const struct super_operations v9fs_super_ops, v9fs_super_ops_dotl; /** * 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 * @flags: flags propagated from v9fs_mount() * */ static void v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses, int flags, void *data) { 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; if (v9fs_proto_dotl(v9ses)) { sb->s_op = &v9fs_super_ops_dotl; sb->s_xattr = v9fs_xattr_handlers; } else sb->s_op = &v9fs_super_ops; sb->s_bdi = &v9ses->bdi; if (v9ses->cache) sb->s_bdi->ra_pages = (VM_MAX_READAHEAD * 1024)/PAGE_CACHE_SIZE; sb->s_flags |= MS_ACTIVE | MS_DIRSYNC | MS_NOATIME; if (!v9ses->cache) sb->s_flags |= MS_SYNCHRONOUS; #ifdef CONFIG_9P_FS_POSIX_ACL if ((v9ses->flags & V9FS_ACL_MASK) == V9FS_POSIX_ACL) sb->s_flags |= MS_POSIXACL; #endif save_mount_options(sb, data); } /** * v9fs_mount - mount a superblock * @fs_type: file system type * @flags: mount flags * @dev_name: device name that was mounted * @data: mount options * */ static struct dentry *v9fs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, void *data) { struct super_block *sb = NULL; struct inode *inode = NULL; struct dentry *root = NULL; struct v9fs_session_info *v9ses = NULL; umode_t mode = S_IRWXUGO | S_ISVTX; struct p9_fid *fid; int retval = 0; p9_debug(P9_DEBUG_VFS, "\n"); v9ses = kzalloc(sizeof(struct v9fs_session_info), GFP_KERNEL); if (!v9ses) return ERR_PTR(-ENOMEM); fid = v9fs_session_init(v9ses, dev_name, data); if (IS_ERR(fid)) { retval = PTR_ERR(fid); /* * we need to call session_close to tear down some * of the data structure setup by session_init */ goto close_session; } sb = sget(fs_type, NULL, v9fs_set_super, flags, v9ses); if (IS_ERR(sb)) { retval = PTR_ERR(sb); goto clunk_fid; } v9fs_fill_super(sb, v9ses, flags, data); if (v9ses->cache) sb->s_d_op = &v9fs_cached_dentry_operations; else sb->s_d_op = &v9fs_dentry_operations; inode = v9fs_get_inode(sb, S_IFDIR | mode, 0); if (IS_ERR(inode)) { retval = PTR_ERR(inode); goto release_sb; } root = d_make_root(inode); if (!root) { retval = -ENOMEM; goto release_sb; } sb->s_root = root; if (v9fs_proto_dotl(v9ses)) { struct p9_stat_dotl *st = NULL; st = p9_client_getattr_dotl(fid, P9_STATS_BASIC); if (IS_ERR(st)) { retval = PTR_ERR(st); goto release_sb; } root->d_inode->i_ino = v9fs_qid2ino(&st->qid); v9fs_stat2inode_dotl(st, root->d_inode); kfree(st); } else { struct p9_wstat *st = NULL; st = p9_client_stat(fid); if (IS_ERR(st)) { retval = PTR_ERR(st); goto release_sb; } root->d_inode->i_ino = v9fs_qid2ino(&st->qid); v9fs_stat2inode(st, root->d_inode, sb); p9stat_free(st); kfree(st); } retval = v9fs_get_acl(inode, fid); if (retval) goto release_sb; v9fs_fid_add(root, fid); p9_debug(P9_DEBUG_VFS, " simple set mount, return 0\n"); return dget(sb->s_root); clunk_fid: p9_client_clunk(fid); close_session: v9fs_session_close(v9ses); kfree(v9ses); return ERR_PTR(retval); release_sb: /* * we will do the session_close and root dentry release * in the below call. But we need to clunk fid, because we haven't * attached the fid to dentry so it won't get clunked * automatically. */ p9_client_clunk(fid); deactivate_locked_super(sb); return ERR_PTR(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_debug(P9_DEBUG_VFS, " %p\n", s); kill_anon_super(s); v9fs_session_cancel(v9ses); v9fs_session_close(v9ses); kfree(v9ses); s->s_fs_info = NULL; p9_debug(P9_DEBUG_VFS, "exiting kill_super\n"); } static void v9fs_umount_begin(struct super_block *sb) { struct v9fs_session_info *v9ses; v9ses = sb->s_fs_info; v9fs_session_begin_cancel(v9ses); } static int v9fs_statfs(struct dentry *dentry, struct kstatfs *buf) { struct v9fs_session_info *v9ses; struct p9_fid *fid; struct p9_rstatfs rs; int res; fid = v9fs_fid_lookup(dentry); if (IS_ERR(fid)) { res = PTR_ERR(fid); goto done; } v9ses = v9fs_dentry2v9ses(dentry); if (v9fs_proto_dotl(v9ses)) { res = p9_client_statfs(fid, &rs); if (res == 0) { buf->f_type = rs.type; buf->f_bsize = rs.bsize; buf->f_blocks = rs.blocks; buf->f_bfree = rs.bfree; buf->f_bavail = rs.bavail; buf->f_files = rs.files; buf->f_ffree = rs.ffree; buf->f_fsid.val[0] = rs.fsid & 0xFFFFFFFFUL; buf->f_fsid.val[1] = (rs.fsid >> 32) & 0xFFFFFFFFUL; buf->f_namelen = rs.namelen; } if (res != -ENOSYS) goto done; } res = simple_statfs(dentry, buf); done: return res; } static int v9fs_drop_inode(struct inode *inode) { struct v9fs_session_info *v9ses; v9ses = v9fs_inode2v9ses(inode); if (v9ses->cache) return generic_drop_inode(inode); /* * in case of non cached mode always drop the * the inode because we want the inode attribute * to always match that on the server. */ return 1; } static int v9fs_write_inode(struct inode *inode, struct writeback_control *wbc) { int ret; struct p9_wstat wstat; struct v9fs_inode *v9inode; /* * send an fsync request to server irrespective of * wbc->sync_mode. */ p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode); v9inode = V9FS_I(inode); if (!v9inode->writeback_fid) return 0; v9fs_blank_wstat(&wstat); ret = p9_client_wstat(v9inode->writeback_fid, &wstat); if (ret < 0) { __mark_inode_dirty(inode, I_DIRTY_DATASYNC); return ret; } return 0; } static int v9fs_write_inode_dotl(struct inode *inode, struct writeback_control *wbc) { int ret; struct v9fs_inode *v9inode; /* * send an fsync request to server irrespective of * wbc->sync_mode. */ p9_debug(P9_DEBUG_VFS, "%s: inode %p\n", __func__, inode); v9inode = V9FS_I(inode); if (!v9inode->writeback_fid) return 0; ret = p9_client_fsync(v9inode->writeback_fid, 0); if (ret < 0) { __mark_inode_dirty(inode, I_DIRTY_DATASYNC); return ret; } return 0; } static const struct super_operations v9fs_super_ops = { .alloc_inode = v9fs_alloc_inode, .destroy_inode = v9fs_destroy_inode, .statfs = simple_statfs, .evict_inode = v9fs_evict_inode, .show_options = generic_show_options, .umount_begin = v9fs_umount_begin, .write_inode = v9fs_write_inode, }; static const struct super_operations v9fs_super_ops_dotl = { .alloc_inode = v9fs_alloc_inode, .destroy_inode = v9fs_destroy_inode, .statfs = v9fs_statfs, .drop_inode = v9fs_drop_inode, .evict_inode = v9fs_evict_inode, .show_options = generic_show_options, .umount_begin = v9fs_umount_begin, .write_inode = v9fs_write_inode_dotl, }; struct file_system_type v9fs_fs_type = { .name = "9p", .mount = v9fs_mount, .kill_sb = v9fs_kill_super, .owner = THIS_MODULE, .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT, };