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