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 #include <linux/slab.h>
  22
  23 #include <asm/system.h>
  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_linux.h>
  31 #include <linux/coda_psdev.h>
  32 #include <linux/coda_fs_i.h>
  33 #include <linux/coda_cache.h>
  34
  35 #include "coda_int.h"
  36
  37 /* VFS super_block ops */
  38 static void coda_evict_inode(struct inode *);
  39 static void coda_put_super(struct super_block *);
  40 static int coda_statfs(struct dentry *dentry, struct kstatfs *buf);
  41
  42 static struct kmem_cache * coda_inode_cachep;
  43
  44 static struct inode *coda_alloc_inode(struct super_block *sb)
  45 {
  46         struct coda_inode_info *ei;
  47         ei = (struct coda_inode_info *)kmem_cache_alloc(coda_inode_cachep, GFP_KERNEL);
  48         if (!ei)
  49                 return NULL;
  50         memset(&ei->c_fid, 0, sizeof(struct CodaFid));
  51         ei->c_flags = 0;
  52         ei->c_uid = 0;
  53         ei->c_cached_perm = 0;
  54         return &ei->vfs_inode;
  55 }
  56
  57 static void coda_destroy_inode(struct inode *inode)
  58 {
  59         kmem_cache_free(coda_inode_cachep, ITOC(inode));
  60 }
  61
  62 static void init_once(void *foo)
  63 {
  64         struct coda_inode_info *ei = (struct coda_inode_info *) foo;
  65
  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);
  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_NOATIME;
  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         .evict_inode    = coda_evict_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 venus_comm *vc = NULL;
 147         struct CodaFid fid;
 148         int error;
 149         int idx;
 150
 151         idx = get_device_index((struct coda_mount_data *) data);
 152
 153         /* Ignore errors in data, for backward compatibility */
 154         if(idx == -1)
 155                 idx = 0;
 156
 157         printk(KERN_INFO "coda_read_super: device index: %i\n", idx);
 158
 159         vc = &coda_comms[idx];
 160         if (!vc->vc_inuse) {
 161                 printk("coda_read_super: No pseudo device\n");
 162                 return -EINVAL;
 163         }
 164
 165         if ( vc->vc_sb ) {
 166                 printk("coda_read_super: Device already mounted\n");
 167                 return -EBUSY;
 168         }
 169
 170         error = bdi_setup_and_register(&vc->bdi, "coda", BDI_CAP_MAP_COPY);
 171         if (error)
 172                 goto bdi_err;
 173
 174         vc->vc_sb = sb;
 175
 176         sb->s_fs_info = vc;
 177         sb->s_flags |= MS_NOATIME;
 178         sb->s_blocksize = 4096; /* XXXXX  what do we put here?? */
 179         sb->s_blocksize_bits = 12;
 180         sb->s_magic = CODA_SUPER_MAGIC;
 181         sb->s_op = &coda_super_operations;
 182         sb->s_bdi = &vc->bdi;
 183
 184         /* get root fid from Venus: this needs the root inode */
 185         error = venus_rootfid(sb, &fid);
 186         if ( error ) {
 187                 printk("coda_read_super: coda_get_rootfid failed with %d\n",
 188                        error);
 189                 goto error;
 190         }
 191         printk("coda_read_super: rootfid is %s\n", coda_f2s(&fid));
 192
 193         /* make root inode */
 194         error = coda_cnode_make(&root, &fid, sb);
 195         if ( error || !root ) {
 196             printk("Failure of coda_cnode_make for root: error %d\n", error);
 197             goto error;
 198         }
 199
 200         printk("coda_read_super: rootinode is %ld dev %s\n",
 201                root->i_ino, root->i_sb->s_id);
 202         sb->s_root = d_alloc_root(root);
 203         if (!sb->s_root)
 204                 goto error;
 205         return 0;
 206
 207  error:
 208         bdi_destroy(&vc->bdi);
 209  bdi_err:
 210         if (root)
 211                 iput(root);
 212         if (vc)
 213                 vc->vc_sb = NULL;
 214
 215         return -EINVAL;
 216 }
 217
 218 static void coda_put_super(struct super_block *sb)
 219 {
 220         bdi_destroy(&coda_vcp(sb)->bdi);
 221         coda_vcp(sb)->vc_sb = NULL;
 222         sb->s_fs_info = NULL;
 223
 224         printk("Coda: Bye bye.\n");
 225 }
 226
 227 static void coda_evict_inode(struct inode *inode)
 228 {
 229         truncate_inode_pages(&inode->i_data, 0);
 230         end_writeback(inode);
 231         coda_cache_clear_inode(inode);
 232 }
 233
 234 int coda_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 235 {
 236         int err = coda_revalidate_inode(dentry);
 237         if (!err)
 238                 generic_fillattr(dentry->d_inode, stat);
 239         return err;
 240 }
 241
 242 int coda_setattr(struct dentry *de, struct iattr *iattr)
 243 {
 244         struct inode *inode = de->d_inode;
 245         struct coda_vattr vattr;
 246         int error;
 247
 248         lock_kernel();
 249
 250         memset(&vattr, 0, sizeof(vattr));
 251
 252         inode->i_ctime = CURRENT_TIME_SEC;
 253         coda_iattr_to_vattr(iattr, &vattr);
 254         vattr.va_type = C_VNON; /* cannot set type */
 255
 256         /* Venus is responsible for truncating the container-file!!! */
 257         error = venus_setattr(inode->i_sb, coda_i2f(inode), &vattr);
 258
 259         if ( !error ) {
 260                 coda_vattr_to_iattr(inode, &vattr);
 261                 coda_cache_clear_inode(inode);
 262         }
 263
 264         unlock_kernel();
 265
 266         return error;
 267 }
 268
 269 const struct inode_operations coda_file_inode_operations = {
 270         .permission     = coda_permission,
 271         .getattr        = coda_getattr,
 272         .setattr        = coda_setattr,
 273 };
 274
 275 static int coda_statfs(struct dentry *dentry, struct kstatfs *buf)
 276 {
 277         int error;
 278
 279         lock_kernel();
 280
 281         error = venus_statfs(dentry, buf);
 282
 283         unlock_kernel();
 284
 285         if (error) {
 286                 /* fake something like AFS does */
 287                 buf->f_blocks = 9000000;
 288                 buf->f_bfree  = 9000000;
 289                 buf->f_bavail = 9000000;
 290                 buf->f_files  = 9000000;
 291                 buf->f_ffree  = 9000000;
 292         }
 293
 294         /* and fill in the rest */
 295         buf->f_type = CODA_SUPER_MAGIC;
 296         buf->f_bsize = 4096;
 297         buf->f_namelen = CODA_MAXNAMLEN;
 298
 299         return 0;
 300 }
 301
 302 /* init_coda: used by filesystems.c to register coda */
 303
 304 static int coda_get_sb(struct file_system_type *fs_type,
 305         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
 306 {
 307         return get_sb_nodev(fs_type, flags, data, coda_fill_super, mnt);
 308 }
 309
 310 struct file_system_type coda_fs_type = {
 311         .owner          = THIS_MODULE,
 312         .name           = "coda",
 313         .get_sb         = coda_get_sb,
 314         .kill_sb        = kill_anon_super,
 315         .fs_flags       = FS_BINARY_MOUNTDATA,
 316 };
 317