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