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 kmem_cache_t * 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, SLAB_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, kmem_cache_t * 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         if (kmem_cache_destroy(coda_inode_cachep))
  84                 printk(KERN_INFO "coda_inode_cache: not all structures were freed\n");
  85 }
  86
  87 static int coda_remount(struct super_block *sb, int *flags, char *data)
  88 {
  89         *flags |= MS_NODIRATIME;
  90         return 0;
  91 }
  92
  93 /* exported operations */
  94 static struct super_operations coda_super_operations =
  95 {
  96         .alloc_inode    = coda_alloc_inode,
  97         .destroy_inode  = coda_destroy_inode,
  98         .clear_inode    = coda_clear_inode,
  99         .put_super      = coda_put_super,
 100         .statfs         = coda_statfs,
 101         .remount_fs     = coda_remount,
 102 };
 103
 104 static int get_device_index(struct coda_mount_data *data)
 105 {
 106         struct file *file;
 107         struct inode *inode;
 108         int idx;
 109
 110         if(data == NULL) {
 111                 printk("coda_read_super: Bad mount data\n");
 112                 return -1;
 113         }
 114
 115         if(data->version != CODA_MOUNT_VERSION) {
 116                 printk("coda_read_super: Bad mount version\n");
 117                 return -1;
 118         }
 119
 120         file = fget(data->fd);
 121         inode = NULL;
 122         if(file)
 123                 inode = file->f_dentry->d_inode;
 124
 125         if(!inode || !S_ISCHR(inode->i_mode) ||
 126            imajor(inode) != CODA_PSDEV_MAJOR) {
 127                 if(file)
 128                         fput(file);
 129
 130                 printk("coda_read_super: Bad file\n");
 131                 return -1;
 132         }
 133
 134         idx = iminor(inode);
 135         fput(file);
 136
 137         if(idx < 0 || idx >= MAX_CODADEVS) {
 138                 printk("coda_read_super: Bad minor number\n");
 139                 return -1;
 140         }
 141
 142         return idx;
 143 }
 144
 145 static int coda_fill_super(struct super_block *sb, void *data, int silent)
 146 {
 147         struct inode *root = NULL;
 148         struct coda_sb_info *sbi = NULL;
 149         struct venus_comm *vc = NULL;
 150         struct CodaFid fid;
 151         int error;
 152         int idx;
 153
 154         idx = get_device_index((struct coda_mount_data *) data);
 155
 156         /* Ignore errors in data, for backward compatibility */
 157         if(idx == -1)
 158                 idx = 0;
 159
 160         printk(KERN_INFO "coda_read_super: device index: %i\n", idx);
 161
 162         vc = &coda_comms[idx];
 163         if (!vc->vc_inuse) {
 164                 printk("coda_read_super: No pseudo device\n");
 165                 return -EINVAL;
 166         }
 167
 168         if ( vc->vc_sb ) {
 169                 printk("coda_read_super: Device already mounted\n");
 170                 return -EBUSY;
 171         }
 172
 173         sbi = kmalloc(sizeof(struct coda_sb_info), GFP_KERNEL);
 174         if(!sbi) {
 175                 return -ENOMEM;
 176         }
 177
 178         vc->vc_sb = sb;
 179
 180         sbi->sbi_vcomm = vc;
 181
 182         sb->s_fs_info = sbi;
 183         sb->s_flags |= MS_NODIRATIME; /* probably even noatime */
 184         sb->s_blocksize = 1024; /* XXXXX  what do we put here?? */
 185         sb->s_blocksize_bits = 10;
 186         sb->s_magic = CODA_SUPER_MAGIC;
 187         sb->s_op = &coda_super_operations;
 188
 189         /* get root fid from Venus: this needs the root inode */
 190         error = venus_rootfid(sb, &fid);
 191         if ( error ) {
 192                 printk("coda_read_super: coda_get_rootfid failed with %d\n",
 193                        error);
 194                 goto error;
 195         }
 196         printk("coda_read_super: rootfid is %s\n", coda_f2s(&fid));
 197
 198         /* make root inode */
 199         error = coda_cnode_make(&root, &fid, sb);
 200         if ( error || !root ) {
 201             printk("Failure of coda_cnode_make for root: error %d\n", error);
 202             goto error;
 203         }
 204
 205         printk("coda_read_super: rootinode is %ld dev %s\n",
 206                root->i_ino, root->i_sb->s_id);
 207         sb->s_root = d_alloc_root(root);
 208         if (!sb->s_root)
 209                 goto error;
 210         return 0;
 211
 212  error:
 213         if (sbi) {
 214                 kfree(sbi);
 215                 if(vc)
 216                         vc->vc_sb = NULL;
 217         }
 218         if (root)
 219                 iput(root);
 220
 221         return -EINVAL;
 222 }
 223
 224 static void coda_put_super(struct super_block *sb)
 225 {
 226         struct coda_sb_info *sbi;
 227
 228         sbi = coda_sbp(sb);
 229         sbi->sbi_vcomm->vc_sb = NULL;
 230
 231         printk("Coda: Bye bye.\n");
 232         kfree(sbi);
 233 }
 234
 235 static void coda_clear_inode(struct inode *inode)
 236 {
 237         coda_cache_clear_inode(inode);
 238 }
 239
 240 int coda_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 241 {
 242         int err = coda_revalidate_inode(dentry);
 243         if (!err)
 244                 generic_fillattr(dentry->d_inode, stat);
 245         return err;
 246 }
 247
 248 int coda_setattr(struct dentry *de, struct iattr *iattr)
 249 {
 250         struct inode *inode = de->d_inode;
 251         struct coda_vattr vattr;
 252         int error;
 253
 254         lock_kernel();
 255
 256         memset(&vattr, 0, sizeof(vattr));
 257
 258         inode->i_ctime = CURRENT_TIME_SEC;
 259         coda_iattr_to_vattr(iattr, &vattr);
 260         vattr.va_type = C_VNON; /* cannot set type */
 261
 262         /* Venus is responsible for truncating the container-file!!! */
 263         error = venus_setattr(inode->i_sb, coda_i2f(inode), &vattr);
 264
 265         if ( !error ) {
 266                 coda_vattr_to_iattr(inode, &vattr);
 267                 coda_cache_clear_inode(inode);
 268         }
 269
 270         unlock_kernel();
 271
 272         return error;
 273 }
 274
 275 struct inode_operations coda_file_inode_operations = {
 276         .permission     = coda_permission,
 277         .getattr        = coda_getattr,
 278         .setattr        = coda_setattr,
 279 };
 280
 281 static int coda_statfs(struct dentry *dentry, struct kstatfs *buf)
 282 {
 283         int error;
 284
 285         lock_kernel();
 286
 287         error = venus_statfs(dentry, buf);
 288
 289         unlock_kernel();
 290
 291         if (error) {
 292                 /* fake something like AFS does */
 293                 buf->f_blocks = 9000000;
 294                 buf->f_bfree  = 9000000;
 295                 buf->f_bavail = 9000000;
 296                 buf->f_files  = 9000000;
 297                 buf->f_ffree  = 9000000;
 298         }
 299
 300         /* and fill in the rest */
 301         buf->f_type = CODA_SUPER_MAGIC;
 302         buf->f_bsize = 1024;
 303         buf->f_namelen = CODA_MAXNAMLEN;
 304
 305         return 0;
 306 }
 307
 308 /* init_coda: used by filesystems.c to register coda */
 309
 310 static int coda_get_sb(struct file_system_type *fs_type,
 311         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
 312 {
 313         return get_sb_nodev(fs_type, flags, data, coda_fill_super, mnt);
 314 }
 315
 316 struct file_system_type coda_fs_type = {
 317         .owner          = THIS_MODULE,
 318         .name           = "coda",
 319         .get_sb         = coda_get_sb,
 320         .kill_sb        = kill_anon_super,
 321         .fs_flags       = FS_BINARY_MOUNTDATA,
 322 };
 323