fs/coda/cnode.c

   1 /* cnode related routines for the coda kernel code
   2    (C) 1996 Peter Braam
   3    */
   4
   5 #include <linux/types.h>
   6 #include <linux/string.h>
   7 #include <linux/time.h>
   8
   9 #include <linux/coda.h>
  10 #include <linux/coda_linux.h>
  11 #include <linux/coda_fs_i.h>
  12 #include <linux/coda_psdev.h>
  13
  14 inline int coda_fideq(ViceFid *fid1, ViceFid *fid2)
  15 {
  16         if (fid1->Vnode != fid2->Vnode)   return 0;
  17         if (fid1->Volume != fid2->Volume) return 0;
  18         if (fid1->Unique != fid2->Unique) return 0;
  19         return 1;
  20 }
  21
  22 inline int coda_isnullfid(ViceFid *fid)
  23 {
  24         if (fid->Vnode || fid->Volume || fid->Unique) return 0;
  25         return 1;
  26 }
  27
  28 static struct inode_operations coda_symlink_inode_operations = {
  29         .readlink       = page_readlink,
  30         .follow_link    = page_follow_link,
  31         .setattr        = coda_setattr,
  32 };
  33
  34 /* cnode.c */
  35 static void coda_fill_inode(struct inode *inode, struct coda_vattr *attr)
  36 {
  37         coda_vattr_to_iattr(inode, attr);
  38
  39         if (S_ISREG(inode->i_mode)) {
  40                 inode->i_op = &coda_file_inode_operations;
  41                 inode->i_fop = &coda_file_operations;
  42         } else if (S_ISDIR(inode->i_mode)) {
  43                 inode->i_op = &coda_dir_inode_operations;
  44                 inode->i_fop = &coda_dir_operations;
  45         } else if (S_ISLNK(inode->i_mode)) {
  46                 inode->i_op = &coda_symlink_inode_operations;
  47                 inode->i_data.a_ops = &coda_symlink_aops;
  48                 inode->i_mapping = &inode->i_data;
  49         } else
  50                 init_special_inode(inode, inode->i_mode, attr->va_rdev);
  51 }
  52
  53 static int coda_test_inode(struct inode *inode, void *data)
  54 {
  55         ViceFid *fid = (ViceFid *)data;
  56         return coda_fideq(&(ITOC(inode)->c_fid), fid);
  57 }
  58
  59 static int coda_set_inode(struct inode *inode, void *data)
  60 {
  61         ViceFid *fid = (ViceFid *)data;
  62         ITOC(inode)->c_fid = *fid;
  63         return 0;
  64 }
  65
  66 static int coda_fail_inode(struct inode *inode, void *data)
  67 {
  68         return -1;
  69 }
  70
  71 struct inode * coda_iget(struct super_block * sb, ViceFid * fid,
  72                          struct coda_vattr * attr)
  73 {
  74         struct inode *inode;
  75         struct coda_inode_info *cii;
  76         struct coda_sb_info *sbi = coda_sbp(sb);
  77         unsigned long hash = coda_f2i(fid);
  78
  79         inode = iget5_locked(sb, hash, coda_test_inode, coda_set_inode, fid);
  80
  81         if (!inode)
  82                 return ERR_PTR(-ENOMEM);
  83
  84         if (inode->i_state & I_NEW) {
  85                 cii = ITOC(inode);
  86                 /* we still need to set i_ino for things like stat(2) */
  87                 inode->i_ino = hash;
  88                 cii->c_mapcount = 0;
  89                 list_add(&cii->c_cilist, &sbi->sbi_cihead);
  90                 unlock_new_inode(inode);
  91         }
  92
  93         /* always replace the attributes, type might have changed */
  94         coda_fill_inode(inode, attr);
  95         return inode;
  96 }
  97
  98 /* this is effectively coda_iget:
  99    - get attributes (might be cached)
 100    - get the inode for the fid using vfs iget
 101    - link the two up if this is needed
 102    - fill in the attributes
 103 */
 104 int coda_cnode_make(struct inode **inode, ViceFid *fid, struct super_block *sb)
 105 {
 106         struct coda_vattr attr;
 107         int error;
 108
 109         /* We get inode numbers from Venus -- see venus source */
 110         error = venus_getattr(sb, fid, &attr);
 111         if ( error ) {
 112             *inode = NULL;
 113             return error;
 114         }
 115
 116         *inode = coda_iget(sb, fid, &attr);
 117         if ( IS_ERR(*inode) ) {
 118                 printk("coda_cnode_make: coda_iget failed\n");
 119                 return PTR_ERR(*inode);
 120         }
 121         return 0;
 122 }
 123
 124
 125 void coda_replace_fid(struct inode *inode, struct ViceFid *oldfid,
 126                       struct ViceFid *newfid)
 127 {
 128         struct coda_inode_info *cii;
 129         unsigned long hash = coda_f2i(newfid);
 130
 131         cii = ITOC(inode);
 132
 133         if (!coda_fideq(&cii->c_fid, oldfid))
 134                 BUG();
 135
 136         /* replace fid and rehash inode */
 137         /* XXX we probably need to hold some lock here! */
 138         remove_inode_hash(inode);
 139         cii->c_fid = *newfid;
 140         inode->i_ino = hash;
 141         __insert_inode_hash(inode, hash);
 142 }
 143
 144 /* convert a fid to an inode. */
 145 struct inode *coda_fid_to_inode(ViceFid *fid, struct super_block *sb)
 146 {
 147         struct inode *inode;
 148         unsigned long hash = coda_f2i(fid);
 149
 150         if ( !sb ) {
 151                 printk("coda_fid_to_inode: no sb!\n");
 152                 return NULL;
 153         }
 154
 155         inode = iget5_locked(sb, hash, coda_test_inode, coda_fail_inode, fid);
 156         if ( !inode )
 157                 return NULL;
 158
 159         /* we should never see newly created inodes because we intentionally
 160          * fail in the initialization callback */
 161         BUG_ON(inode->i_state & I_NEW);
 162
 163         return inode;
 164 }
 165
 166 /* the CONTROL inode is made without asking attributes from Venus */
 167 int coda_cnode_makectl(struct inode **inode, struct super_block *sb)
 168 {
 169         int error = -ENOMEM;
 170
 171         *inode = new_inode(sb);
 172         if (*inode) {
 173                 (*inode)->i_ino = CTL_INO;
 174                 (*inode)->i_op = &coda_ioctl_inode_operations;
 175                 (*inode)->i_fop = &coda_ioctl_operations;
 176                 (*inode)->i_mode = 0444;
 177                 error = 0;
 178         }
 179
 180         return error;
 181 }
 182