1 /* 2 * Super block/filesystem wide operations 3 * 4 * Copyright (C) 1996 Peter J. Braam <braam@maths.ox.ac.uk> and 5 * Michael Callahan <callahan@maths.ox.ac.uk> 6 * 7 * Rewritten for Linux 2.1. Peter Braam <braam@cs.cmu.edu> 8 * Copyright (C) Carnegie Mellon University 9 */ 10 11 #include <linux/module.h> 12 #include <linux/kernel.h> 13 #include <linux/mm.h> 14 #include <linux/string.h> 15 #include <linux/stat.h> 16 #include <linux/errno.h> 17 #include <linux/unistd.h> 18 #include <linux/mutex.h> 19 #include <linux/spinlock.h> 20 #include <linux/file.h> 21 #include <linux/vfs.h> 22 #include <linux/slab.h> 23 24 #include <asm/system.h> 25 #include <asm/uaccess.h> 26 27 #include <linux/fs.h> 28 #include <linux/vmalloc.h> 29 30 #include <linux/coda.h> 31 #include <linux/coda_psdev.h> 32 #include "coda_linux.h" 33 #include "coda_cache.h" 34 35 #include "coda_int.h" 36 37 /* VFS super_block ops */ 38 static void coda_evict_inode(struct inode *); 39 static void coda_put_super(struct super_block *); 40 static int coda_statfs(struct dentry *dentry, struct kstatfs *buf); 41 42 static struct kmem_cache * coda_inode_cachep; 43 44 static struct inode *coda_alloc_inode(struct super_block *sb) 45 { 46 struct coda_inode_info *ei; 47 ei = kmem_cache_alloc(coda_inode_cachep, GFP_KERNEL); 48 if (!ei) 49 return NULL; 50 memset(&ei->c_fid, 0, sizeof(struct CodaFid)); 51 ei->c_flags = 0; 52 ei->c_uid = 0; 53 ei->c_cached_perm = 0; 54 spin_lock_init(&ei->c_lock); 55 return &ei->vfs_inode; 56 } 57 58 static void coda_i_callback(struct rcu_head *head) 59 { 60 struct inode *inode = container_of(head, struct inode, i_rcu); 61 kmem_cache_free(coda_inode_cachep, ITOC(inode)); 62 } 63 64 static void coda_destroy_inode(struct inode *inode) 65 { 66 call_rcu(&inode->i_rcu, coda_i_callback); 67 } 68 69 static void init_once(void *foo) 70 { 71 struct coda_inode_info *ei = (struct coda_inode_info *) foo; 72 73 inode_init_once(&ei->vfs_inode); 74 } 75 76 int coda_init_inodecache(void) 77 { 78 coda_inode_cachep = kmem_cache_create("coda_inode_cache", 79 sizeof(struct coda_inode_info), 80 0, SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, 81 init_once); 82 if (coda_inode_cachep == NULL) 83 return -ENOMEM; 84 return 0; 85 } 86 87 void coda_destroy_inodecache(void) 88 { 89 kmem_cache_destroy(coda_inode_cachep); 90 } 91 92 static int coda_remount(struct super_block *sb, int *flags, char *data) 93 { 94 *flags |= MS_NOATIME; 95 return 0; 96 } 97 98 /* exported operations */ 99 static const struct super_operations coda_super_operations = 100 { 101 .alloc_inode = coda_alloc_inode, 102 .destroy_inode = coda_destroy_inode, 103 .evict_inode = coda_evict_inode, 104 .put_super = coda_put_super, 105 .statfs = coda_statfs, 106 .remount_fs = coda_remount, 107 }; 108 109 static int get_device_index(struct coda_mount_data *data) 110 { 111 struct file *file; 112 struct inode *inode; 113 int idx; 114 115 if(data == NULL) { 116 printk("coda_read_super: Bad mount data\n"); 117 return -1; 118 } 119 120 if(data->version != CODA_MOUNT_VERSION) { 121 printk("coda_read_super: Bad mount version\n"); 122 return -1; 123 } 124 125 file = fget(data->fd); 126 inode = NULL; 127 if(file) 128 inode = file->f_path.dentry->d_inode; 129 130 if(!inode || !S_ISCHR(inode->i_mode) || 131 imajor(inode) != CODA_PSDEV_MAJOR) { 132 if(file) 133 fput(file); 134 135 printk("coda_read_super: Bad file\n"); 136 return -1; 137 } 138 139 idx = iminor(inode); 140 fput(file); 141 142 if(idx < 0 || idx >= MAX_CODADEVS) { 143 printk("coda_read_super: Bad minor number\n"); 144 return -1; 145 } 146 147 return idx; 148 } 149 150 static int coda_fill_super(struct super_block *sb, void *data, int silent) 151 { 152 struct inode *root = NULL; 153 struct venus_comm *vc; 154 struct CodaFid fid; 155 int error; 156 int idx; 157 158 idx = get_device_index((struct coda_mount_data *) data); 159 160 /* Ignore errors in data, for backward compatibility */ 161 if(idx == -1) 162 idx = 0; 163 164 printk(KERN_INFO "coda_read_super: device index: %i\n", idx); 165 166 vc = &coda_comms[idx]; 167 mutex_lock(&vc->vc_mutex); 168 169 if (!vc->vc_inuse) { 170 printk("coda_read_super: No pseudo device\n"); 171 error = -EINVAL; 172 goto unlock_out; 173 } 174 175 if (vc->vc_sb) { 176 printk("coda_read_super: Device already mounted\n"); 177 error = -EBUSY; 178 goto unlock_out; 179 } 180 181 error = bdi_setup_and_register(&vc->bdi, "coda", BDI_CAP_MAP_COPY); 182 if (error) 183 goto unlock_out; 184 185 vc->vc_sb = sb; 186 mutex_unlock(&vc->vc_mutex); 187 188 sb->s_fs_info = vc; 189 sb->s_flags |= MS_NOATIME; 190 sb->s_blocksize = 4096; /* XXXXX what do we put here?? */ 191 sb->s_blocksize_bits = 12; 192 sb->s_magic = CODA_SUPER_MAGIC; 193 sb->s_op = &coda_super_operations; 194 sb->s_d_op = &coda_dentry_operations; 195 sb->s_bdi = &vc->bdi; 196 197 /* get root fid from Venus: this needs the root inode */ 198 error = venus_rootfid(sb, &fid); 199 if ( error ) { 200 printk("coda_read_super: coda_get_rootfid failed with %d\n", 201 error); 202 goto error; 203 } 204 printk("coda_read_super: rootfid is %s\n", coda_f2s(&fid)); 205 206 /* make root inode */ 207 root = coda_cnode_make(&fid, sb); 208 if (IS_ERR(root)) { 209 error = PTR_ERR(root); 210 printk("Failure of coda_cnode_make for root: error %d\n", error); 211 goto error; 212 } 213 214 printk("coda_read_super: rootinode is %ld dev %s\n", 215 root->i_ino, root->i_sb->s_id); 216 sb->s_root = d_make_root(root); 217 if (!sb->s_root) { 218 error = -EINVAL; 219 goto error; 220 } 221 return 0; 222 223 error: 224 mutex_lock(&vc->vc_mutex); 225 bdi_destroy(&vc->bdi); 226 vc->vc_sb = NULL; 227 sb->s_fs_info = NULL; 228 unlock_out: 229 mutex_unlock(&vc->vc_mutex); 230 return error; 231 } 232 233 static void coda_put_super(struct super_block *sb) 234 { 235 struct venus_comm *vcp = coda_vcp(sb); 236 mutex_lock(&vcp->vc_mutex); 237 bdi_destroy(&vcp->bdi); 238 vcp->vc_sb = NULL; 239 sb->s_fs_info = NULL; 240 mutex_unlock(&vcp->vc_mutex); 241 242 printk("Coda: Bye bye.\n"); 243 } 244 245 static void coda_evict_inode(struct inode *inode) 246 { 247 truncate_inode_pages(&inode->i_data, 0); 248 end_writeback(inode); 249 coda_cache_clear_inode(inode); 250 } 251 252 int coda_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) 253 { 254 int err = coda_revalidate_inode(dentry); 255 if (!err) 256 generic_fillattr(dentry->d_inode, stat); 257 return err; 258 } 259 260 int coda_setattr(struct dentry *de, struct iattr *iattr) 261 { 262 struct inode *inode = de->d_inode; 263 struct coda_vattr vattr; 264 int error; 265 266 memset(&vattr, 0, sizeof(vattr)); 267 268 inode->i_ctime = CURRENT_TIME_SEC; 269 coda_iattr_to_vattr(iattr, &vattr); 270 vattr.va_type = C_VNON; /* cannot set type */ 271 272 /* Venus is responsible for truncating the container-file!!! */ 273 error = venus_setattr(inode->i_sb, coda_i2f(inode), &vattr); 274 275 if (!error) { 276 coda_vattr_to_iattr(inode, &vattr); 277 coda_cache_clear_inode(inode); 278 } 279 return error; 280 } 281 282 const struct inode_operations coda_file_inode_operations = { 283 .permission = coda_permission, 284 .getattr = coda_getattr, 285 .setattr = coda_setattr, 286 }; 287 288 static int coda_statfs(struct dentry *dentry, struct kstatfs *buf) 289 { 290 int error; 291 292 error = venus_statfs(dentry, buf); 293 294 if (error) { 295 /* fake something like AFS does */ 296 buf->f_blocks = 9000000; 297 buf->f_bfree = 9000000; 298 buf->f_bavail = 9000000; 299 buf->f_files = 9000000; 300 buf->f_ffree = 9000000; 301 } 302 303 /* and fill in the rest */ 304 buf->f_type = CODA_SUPER_MAGIC; 305 buf->f_bsize = 4096; 306 buf->f_namelen = CODA_MAXNAMLEN; 307 308 return 0; 309 } 310 311 /* init_coda: used by filesystems.c to register coda */ 312 313 static struct dentry *coda_mount(struct file_system_type *fs_type, 314 int flags, const char *dev_name, void *data) 315 { 316 return mount_nodev(fs_type, flags, data, coda_fill_super); 317 } 318 319 struct file_system_type coda_fs_type = { 320 .owner = THIS_MODULE, 321 .name = "coda", 322 .mount = coda_mount, 323 .kill_sb = kill_anon_super, 324 .fs_flags = FS_BINARY_MOUNTDATA, 325 }; 326 327