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/mutex.h>
  19 #include <linux/spinlock.h>
  20 #include <linux/file.h>
  21 #include <linux/vfs.h>
  22 #include <linux/slab.h>
  23
  24 #include <asm/system.h>
  25 #include <asm/uaccess.h>
  26
  27 #include <linux/fs.h>
  28 #include <linux/vmalloc.h>
  29
  30 #include <linux/coda.h>
  31 #include <linux/coda_linux.h>
  32 #include <linux/coda_psdev.h>
  33 #include <linux/coda_fs_i.h>
  34 #include <linux/coda_cache.h>
  35
  36 #include "coda_int.h"
  37
  38 /* VFS super_block ops */
  39 static void coda_evict_inode(struct inode *);
  40 static void coda_put_super(struct super_block *);
  41 static int coda_statfs(struct dentry *dentry, struct kstatfs *buf);
  42
  43 static struct kmem_cache * coda_inode_cachep;
  44
  45 static struct inode *coda_alloc_inode(struct super_block *sb)
  46 {
  47         struct coda_inode_info *ei;
  48         ei = (struct coda_inode_info *)kmem_cache_alloc(coda_inode_cachep, GFP_KERNEL);
  49         if (!ei)
  50                 return NULL;
  51         memset(&ei->c_fid, 0, sizeof(struct CodaFid));
  52         ei->c_flags = 0;
  53         ei->c_uid = 0;
  54         ei->c_cached_perm = 0;
  55         spin_lock_init(&ei->c_lock);
  56         return &ei->vfs_inode;
  57 }
  58
  59 static void coda_destroy_inode(struct inode *inode)
  60 {
  61         kmem_cache_free(coda_inode_cachep, ITOC(inode));
  62 }
  63
  64 static void init_once(void *foo)
  65 {
  66         struct coda_inode_info *ei = (struct coda_inode_info *) foo;
  67
  68         inode_init_once(&ei->vfs_inode);
  69 }
  70
  71 int coda_init_inodecache(void)
  72 {
  73         coda_inode_cachep = kmem_cache_create("coda_inode_cache",
  74                                 sizeof(struct coda_inode_info),
  75                                 0, SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
  76                                 init_once);
  77         if (coda_inode_cachep == NULL)
  78                 return -ENOMEM;
  79         return 0;
  80 }
  81
  82 void coda_destroy_inodecache(void)
  83 {
  84         kmem_cache_destroy(coda_inode_cachep);
  85 }
  86
  87 static int coda_remount(struct super_block *sb, int *flags, char *data)
  88 {
  89         *flags |= MS_NOATIME;
  90         return 0;
  91 }
  92
  93 /* exported operations */
  94 static const struct super_operations coda_super_operations =
  95 {
  96         .alloc_inode    = coda_alloc_inode,
  97         .destroy_inode  = coda_destroy_inode,
  98         .evict_inode    = coda_evict_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_path.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 venus_comm *vc;
 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         mutex_lock(&vc->vc_mutex);
 163
 164         if (!vc->vc_inuse) {
 165                 printk("coda_read_super: No pseudo device\n");
 166                 error = -EINVAL;
 167                 goto unlock_out;
 168         }
 169
 170         if (vc->vc_sb) {
 171                 printk("coda_read_super: Device already mounted\n");
 172                 error = -EBUSY;
 173                 goto unlock_out;
 174         }
 175
 176         error = bdi_setup_and_register(&vc->bdi, "coda", BDI_CAP_MAP_COPY);
 177         if (error)
 178                 goto unlock_out;
 179
 180         vc->vc_sb = sb;
 181         mutex_unlock(&vc->vc_mutex);
 182
 183         sb->s_fs_info = vc;
 184         sb->s_flags |= MS_NOATIME;
 185         sb->s_blocksize = 4096; /* XXXXX  what do we put here?? */
 186         sb->s_blocksize_bits = 12;
 187         sb->s_magic = CODA_SUPER_MAGIC;
 188         sb->s_op = &coda_super_operations;
 189         sb->s_bdi = &vc->bdi;
 190
 191         /* get root fid from Venus: this needs the root inode */
 192         error = venus_rootfid(sb, &fid);
 193         if ( error ) {
 194                 printk("coda_read_super: coda_get_rootfid failed with %d\n",
 195                        error);
 196                 goto error;
 197         }
 198         printk("coda_read_super: rootfid is %s\n", coda_f2s(&fid));
 199
 200         /* make root inode */
 201         error = coda_cnode_make(&root, &fid, sb);
 202         if ( error || !root ) {
 203             printk("Failure of coda_cnode_make for root: error %d\n", error);
 204             goto error;
 205         }
 206
 207         printk("coda_read_super: rootinode is %ld dev %s\n",
 208                root->i_ino, root->i_sb->s_id);
 209         sb->s_root = d_alloc_root(root);
 210         if (!sb->s_root) {
 211                 error = -EINVAL;
 212                 goto error;
 213         }
 214         return 0;
 215
 216 error:
 217         if (root)
 218                 iput(root);
 219
 220         mutex_lock(&vc->vc_mutex);
 221         bdi_destroy(&vc->bdi);
 222         vc->vc_sb = NULL;
 223         sb->s_fs_info = NULL;
 224 unlock_out:
 225         mutex_unlock(&vc->vc_mutex);
 226         return error;
 227 }
 228
 229 static void coda_put_super(struct super_block *sb)
 230 {
 231         struct venus_comm *vcp = coda_vcp(sb);
 232         mutex_lock(&vcp->vc_mutex);
 233         bdi_destroy(&vcp->bdi);
 234         vcp->vc_sb = NULL;
 235         sb->s_fs_info = NULL;
 236         mutex_unlock(&vcp->vc_mutex);
 237
 238         printk("Coda: Bye bye.\n");
 239 }
 240
 241 static void coda_evict_inode(struct inode *inode)
 242 {
 243         truncate_inode_pages(&inode->i_data, 0);
 244         end_writeback(inode);
 245         coda_cache_clear_inode(inode);
 246 }
 247
 248 int coda_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 249 {
 250         int err = coda_revalidate_inode(dentry);
 251         if (!err)
 252                 generic_fillattr(dentry->d_inode, stat);
 253         return err;
 254 }
 255
 256 int coda_setattr(struct dentry *de, struct iattr *iattr)
 257 {
 258         struct inode *inode = de->d_inode;
 259         struct coda_vattr vattr;
 260         int error;
 261
 262         memset(&vattr, 0, sizeof(vattr));
 263
 264         inode->i_ctime = CURRENT_TIME_SEC;
 265         coda_iattr_to_vattr(iattr, &vattr);
 266         vattr.va_type = C_VNON; /* cannot set type */
 267
 268         /* Venus is responsible for truncating the container-file!!! */
 269         error = venus_setattr(inode->i_sb, coda_i2f(inode), &vattr);
 270
 271         if (!error) {
 272                 coda_vattr_to_iattr(inode, &vattr);
 273                 coda_cache_clear_inode(inode);
 274         }
 275         return error;
 276 }
 277
 278 const struct inode_operations coda_file_inode_operations = {
 279         .permission     = coda_permission,
 280         .getattr        = coda_getattr,
 281         .setattr        = coda_setattr,
 282 };
 283
 284 static int coda_statfs(struct dentry *dentry, struct kstatfs *buf)
 285 {
 286         int error;
 287
 288         error = venus_statfs(dentry, buf);
 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 = 4096;
 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 struct dentry *coda_mount(struct file_system_type *fs_type,
 310         int flags, const char *dev_name, void *data)
 311 {
 312         return mount_nodev(fs_type, flags, data, coda_fill_super);
 313 }
 314
 315 struct file_system_type coda_fs_type = {
 316         .owner          = THIS_MODULE,
 317         .name           = "coda",
 318         .mount          = coda_mount,
 319         .kill_sb        = kill_anon_super,
 320         .fs_flags       = FS_BINARY_MOUNTDATA,
 321 };
 322