1 /* 2 * linux/fs/9p/vfs_dir.c 3 * 4 * This file contains vfs directory ops for the 9P2000 protocol. 5 * 6 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com> 7 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov> 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License version 2 11 * as published by the Free Software Foundation. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to: 20 * Free Software Foundation 21 * 51 Franklin Street, Fifth Floor 22 * Boston, MA 02111-1301 USA 23 * 24 */ 25 26 #include <linux/module.h> 27 #include <linux/errno.h> 28 #include <linux/fs.h> 29 #include <linux/file.h> 30 #include <linux/stat.h> 31 #include <linux/string.h> 32 #include <linux/smp_lock.h> 33 #include <linux/sched.h> 34 #include <linux/inet.h> 35 #include <linux/idr.h> 36 37 #include "debug.h" 38 #include "v9fs.h" 39 #include "9p.h" 40 #include "conv.h" 41 #include "v9fs_vfs.h" 42 #include "fid.h" 43 44 /** 45 * dt_type - return file type 46 * @mistat: mistat structure 47 * 48 */ 49 50 static inline int dt_type(struct v9fs_stat *mistat) 51 { 52 unsigned long perm = mistat->mode; 53 int rettype = DT_REG; 54 55 if (perm & V9FS_DMDIR) 56 rettype = DT_DIR; 57 if (perm & V9FS_DMSYMLINK) 58 rettype = DT_LNK; 59 60 return rettype; 61 } 62 63 /** 64 * v9fs_dir_readdir - read a directory 65 * @filep: opened file structure 66 * @dirent: directory structure ??? 67 * @filldir: function to populate directory structure ??? 68 * 69 */ 70 71 static int v9fs_dir_readdir(struct file *filp, void *dirent, filldir_t filldir) 72 { 73 struct v9fs_fcall *fcall = NULL; 74 struct inode *inode = filp->f_path.dentry->d_inode; 75 struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode); 76 struct v9fs_fid *file = filp->private_data; 77 unsigned int i, n, s; 78 int fid = -1; 79 int ret = 0; 80 struct v9fs_stat stat; 81 int over = 0; 82 83 dprintk(DEBUG_VFS, "name %s\n", filp->f_path.dentry->d_name.name); 84 85 fid = file->fid; 86 87 if (file->rdir_fcall && (filp->f_pos != file->rdir_pos)) { 88 kfree(file->rdir_fcall); 89 file->rdir_fcall = NULL; 90 } 91 92 if (file->rdir_fcall) { 93 n = file->rdir_fcall->params.rread.count; 94 i = file->rdir_fpos; 95 while (i < n) { 96 s = v9fs_deserialize_stat( 97 file->rdir_fcall->params.rread.data + i, 98 n - i, &stat, v9ses->extended); 99 100 if (s == 0) { 101 dprintk(DEBUG_ERROR, 102 "error while deserializing stat\n"); 103 ret = -EIO; 104 goto FreeStructs; 105 } 106 107 over = filldir(dirent, stat.name.str, stat.name.len, 108 filp->f_pos, v9fs_qid2ino(&stat.qid), 109 dt_type(&stat)); 110 111 if (over) { 112 file->rdir_fpos = i; 113 file->rdir_pos = filp->f_pos; 114 break; 115 } 116 117 i += s; 118 filp->f_pos += s; 119 } 120 121 if (!over) { 122 kfree(file->rdir_fcall); 123 file->rdir_fcall = NULL; 124 } 125 } 126 127 while (!over) { 128 ret = v9fs_t_read(v9ses, fid, filp->f_pos, 129 v9ses->maxdata-V9FS_IOHDRSZ, &fcall); 130 if (ret < 0) { 131 dprintk(DEBUG_ERROR, "error while reading: %d: %p\n", 132 ret, fcall); 133 goto FreeStructs; 134 } else if (ret == 0) 135 break; 136 137 n = ret; 138 i = 0; 139 while (i < n) { 140 s = v9fs_deserialize_stat(fcall->params.rread.data + i, 141 n - i, &stat, v9ses->extended); 142 143 if (s == 0) { 144 dprintk(DEBUG_ERROR, 145 "error while deserializing stat\n"); 146 return -EIO; 147 } 148 149 over = filldir(dirent, stat.name.str, stat.name.len, 150 filp->f_pos, v9fs_qid2ino(&stat.qid), 151 dt_type(&stat)); 152 153 if (over) { 154 file->rdir_fcall = fcall; 155 file->rdir_fpos = i; 156 file->rdir_pos = filp->f_pos; 157 fcall = NULL; 158 break; 159 } 160 161 i += s; 162 filp->f_pos += s; 163 } 164 165 kfree(fcall); 166 } 167 168 FreeStructs: 169 kfree(fcall); 170 return ret; 171 } 172 173 /** 174 * v9fs_dir_release - close a directory 175 * @inode: inode of the directory 176 * @filp: file pointer to a directory 177 * 178 */ 179 180 int v9fs_dir_release(struct inode *inode, struct file *filp) 181 { 182 struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode); 183 struct v9fs_fid *fid = filp->private_data; 184 int fidnum = -1; 185 186 dprintk(DEBUG_VFS, "inode: %p filp: %p fid: %d\n", inode, filp, 187 fid->fid); 188 fidnum = fid->fid; 189 190 filemap_write_and_wait(inode->i_mapping); 191 192 if (fidnum >= 0) { 193 dprintk(DEBUG_VFS, "fidopen: %d v9f->fid: %d\n", fid->fidopen, 194 fid->fid); 195 196 if (v9fs_t_clunk(v9ses, fidnum)) 197 dprintk(DEBUG_ERROR, "clunk failed\n"); 198 199 kfree(fid->rdir_fcall); 200 kfree(fid); 201 202 filp->private_data = NULL; 203 } 204 205 return 0; 206 } 207 208 const struct file_operations v9fs_dir_operations = { 209 .read = generic_read_dir, 210 .readdir = v9fs_dir_readdir, 211 .open = v9fs_file_open, 212 .release = v9fs_dir_release, 213 }; 214