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