fs/coda/inode.c

   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/smp_lock.h>
  19 #include <linux/file.h>
  20 #include <linux/vfs.h>
  21
  22 #include <asm/system.h>
  23 #include <asm/uaccess.h>
  24
  25 #include <linux/fs.h>
  26 #include <linux/vmalloc.h>
  27
  28 #include <linux/coda.h>
  29 #include <linux/coda_linux.h>
  30 #include <linux/coda_psdev.h>
  31 #include <linux/coda_fs_i.h>
  32 #include <linux/coda_cache.h>
  33
  34 #include "coda_int.h"
  35
  36 /* VFS super_block ops */
  37 static void coda_clear_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 = (struct coda_inode_info *)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         return &ei->vfs_inode;
  54 }
  55
  56 static void coda_destroy_inode(struct inode *inode)
  57 {
  58         kmem_cache_free(coda_inode_cachep, ITOC(inode));
  59 }
  60
  61 static void init_once(void * foo, struct kmem_cache * cachep, unsigned long flags)
  62 {
  63         struct coda_inode_info *ei = (struct coda_inode_info *) foo;
  64
  65         if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
  66             SLAB_CTOR_CONSTRUCTOR)
  67                 inode_init_once(&ei->vfs_inode);
  68 }
  69
  70 int coda_init_inodecache(void)
  71 {
  72         coda_inode_cachep = kmem_cache_create("coda_inode_cache",
  73                                 sizeof(struct coda_inode_info),
  74                                 0, SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
  75                                 init_once, NULL);
  76         if (coda_inode_cachep == NULL)
  77                 return -ENOMEM;
  78         return 0;
  79 }
  80
  81 void coda_destroy_inodecache(void)
  82 {
  83         kmem_cache_destroy(coda_inode_cachep);
  84 }
  85
  86 static int coda_remount(struct super_block *sb, int *flags, char *data)
  87 {
  88         *flags |= MS_NODIRATIME;
  89         return 0;
  90 }
  91
  92 /* exported operations */
  93 static struct super_operations coda_super_operations =
  94 {
  95         .alloc_inode    = coda_alloc_inode,
  96         .destroy_inode  = coda_destroy_inode,
  97         .clear_inode    = coda_clear_inode,
  98         .put_super      = coda_put_super,
  99         .statfs         = coda_statfs,
 100         .remount_fs     = coda_remount,
 101 };
 102
 103 static int get_device_index(struct coda_mount_data *data)
 104 {
 105         struct file *file;
 106         struct inode *inode;
 107         int idx;
 108
 109         if(data == NULL) {
 110                 printk("coda_read_super: Bad mount data\n");
 111                 return -1;
 112         }
 113
 114         if(data->version != CODA_MOUNT_VERSION) {
 115                 printk("coda_read_super: Bad mount version\n");
 116                 return -1;
 117         }
 118
 119         file = fget(data->fd);
 120         inode = NULL;
 121         if(file)
 122                 inode = file->f_path.dentry->d_inode;
 123
 124         if(!inode || !S_ISCHR(inode->i_mode) ||
 125            imajor(inode) != CODA_PSDEV_MAJOR) {
 126                 if(file)
 127                         fput(file);
 128
 129                 printk("coda_read_super: Bad file\n");
 130                 return -1;
 131         }
 132
 133         idx = iminor(inode);
 134         fput(file);
 135
 136         if(idx < 0 || idx >= MAX_CODADEVS) {
 137                 printk("coda_read_super: Bad minor number\n");
 138                 return -1;
 139         }
 140
 141         return idx;
 142 }
 143
 144 static int coda_fill_super(struct super_block *sb, void *data, int silent)
 145 {
 146         struct inode *root = NULL;
 147         struct coda_sb_info *sbi = NULL;
 148         struct venus_comm *vc = NULL;
 149         struct CodaFid fid;
 150         int error;
 151         int idx;
 152
 153         idx = get_device_index((struct coda_mount_data *) data);
 154
 155         /* Ignore errors in data, for backward compatibility */
 156         if(idx == -1)
 157                 idx = 0;
 158
 159         printk(KERN_INFO "coda_read_super: device index: %i\n", idx);
 160
 161         vc = &coda_comms[idx];
 162         if (!vc->vc_inuse) {
 163                 printk("coda_read_super: No pseudo device\n");
 164                 return -EINVAL;
 165         }
 166
 167         if ( vc->vc_sb ) {
 168                 printk("coda_read_super: Device already mounted\n");
 169                 return -EBUSY;
 170         }
 171
 172         sbi = kmalloc(sizeof(struct coda_sb_info), GFP_KERNEL);
 173         if(!sbi) {
 174                 return -ENOMEM;
 175         }
 176
 177         vc->vc_sb = sb;
 178
 179         sbi->sbi_vcomm = vc;
 180
 181         sb->s_fs_info = sbi;
 182         sb->s_flags |= MS_NODIRATIME; /* probably even noatime */
 183         sb->s_blocksize = 1024; /* XXXXX  what do we put here?? */
 184         sb->s_blocksize_bits = 10;
 185         sb->s_magic = CODA_SUPER_MAGIC;
 186         sb->s_op = &coda_super_operations;
 187
 188         /* get root fid from Venus: this needs the root inode */
 189         error = venus_rootfid(sb, &fid);
 190         if ( error ) {
 191                 printk("coda_read_super: coda_get_rootfid failed with %d\n",
 192                        error);
 193                 goto error;
 194         }
 195         printk("coda_read_super: rootfid is %s\n", coda_f2s(&fid));
 196
 197         /* make root inode */
 198         error = coda_cnode_make(&root, &fid, sb);
 199         if ( error || !root ) {
 200             printk("Failure of coda_cnode_make for root: error %d\n", error);
 201             goto error;
 202         }
 203
 204         printk("coda_read_super: rootinode is %ld dev %s\n",
 205                root->i_ino, root->i_sb->s_id);
 206         sb->s_root = d_alloc_root(root);
 207         if (!sb->s_root)
 208                 goto error;
 209         return 0;
 210
 211  error:
 212         if (sbi) {
 213                 kfree(sbi);
 214                 if(vc)
 215                         vc->vc_sb = NULL;
 216         }
 217         if (root)
 218                 iput(root);
 219
 220         return -EINVAL;
 221 }
 222
 223 static void coda_put_super(struct super_block *sb)
 224 {
 225         struct coda_sb_info *sbi;
 226
 227         sbi = coda_sbp(sb);
 228         sbi->sbi_vcomm->vc_sb = NULL;
 229
 230         printk("Coda: Bye bye.\n");
 231         kfree(sbi);
 232 }
 233
 234 static void coda_clear_inode(struct inode *inode)
 235 {
 236         coda_cache_clear_inode(inode);
 237 }
 238
 239 int coda_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 240 {
 241         int err = coda_revalidate_inode(dentry);
 242         if (!err)
 243                 generic_fillattr(dentry->d_inode, stat);
 244         return err;
 245 }
 246
 247 int coda_setattr(struct dentry *de, struct iattr *iattr)
 248 {
 249         struct inode *inode = de->d_inode;
 250         struct coda_vattr vattr;
 251         int error;
 252
 253         lock_kernel();
 254
 255         memset(&vattr, 0, sizeof(vattr));
 256
 257         inode->i_ctime = CURRENT_TIME_SEC;
 258         coda_iattr_to_vattr(iattr, &vattr);
 259         vattr.va_type = C_VNON; /* cannot set type */
 260
 261         /* Venus is responsible for truncating the container-file!!! */
 262         error = venus_setattr(inode->i_sb, coda_i2f(inode), &vattr);
 263
 264         if ( !error ) {
 265                 coda_vattr_to_iattr(inode, &vattr);
 266                 coda_cache_clear_inode(inode);
 267         }
 268
 269         unlock_kernel();
 270
 271         return error;
 272 }
 273
 274 struct inode_operations coda_file_inode_operations = {
 275         .permission     = coda_permission,
 276         .getattr        = coda_getattr,
 277         .setattr        = coda_setattr,
 278 };
 279
 280 static int coda_statfs(struct dentry *dentry, struct kstatfs *buf)
 281 {
 282         int error;
 283
 284         lock_kernel();
 285
 286         error = venus_statfs(dentry, buf);
 287
 288         unlock_kernel();
 289
 290         if (error) {
 291                 /* fake something like AFS does */
 292                 buf->f_blocks = 9000000;
 293                 buf->f_bfree  = 9000000;
 294                 buf->f_bavail = 9000000;
 295                 buf->f_files  = 9000000;
 296                 buf->f_ffree  = 9000000;
 297         }
 298
 299         /* and fill in the rest */
 300         buf->f_type = CODA_SUPER_MAGIC;
 301         buf->f_bsize = 1024;
 302         buf->f_namelen = CODA_MAXNAMLEN;
 303
 304         return 0;
 305 }
 306
 307 /* init_coda: used by filesystems.c to register coda */
 308
 309 static int coda_get_sb(struct file_system_type *fs_type,
 310         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
 311 {
 312         return get_sb_nodev(fs_type, flags, data, coda_fill_super, mnt);
 313 }
 314
 315 struct file_system_type coda_fs_type = {
 316         .owner          = THIS_MODULE,
 317         .name           = "coda",
 318         .get_sb         = coda_get_sb,
 319         .kill_sb        = kill_anon_super,
 320         .fs_flags       = FS_BINARY_MOUNTDATA,
 321 };
 322