release/src-rt-6.x/linux/linux-2.6/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 static inline int coda_fideq(struct CodaFid *fid1, struct CodaFid *fid2)
  15 {
  16         return memcmp(fid1, fid2, sizeof(*fid1)) == 0;
  17 }
  18
  19 static const struct inode_operations coda_symlink_inode_operations = {
  20         .readlink       = generic_readlink,
  21         .follow_link    = page_follow_link_light,
  22         .put_link       = page_put_link,
  23         .setattr        = coda_setattr,
  24 };
  25
  26 /* cnode.c */
  27 static void coda_fill_inode(struct inode *inode, struct coda_vattr *attr)
  28 {
  29         coda_vattr_to_iattr(inode, attr);
  30
  31         if (S_ISREG(inode->i_mode)) {
  32                 inode->i_op = &coda_file_inode_operations;
  33                 inode->i_fop = &coda_file_operations;
  34         } else if (S_ISDIR(inode->i_mode)) {
  35                 inode->i_op = &coda_dir_inode_operations;
  36                 inode->i_fop = &coda_dir_operations;
  37         } else if (S_ISLNK(inode->i_mode)) {
  38                 inode->i_op = &coda_symlink_inode_operations;
  39                 inode->i_data.a_ops = &coda_symlink_aops;
  40                 inode->i_mapping = &inode->i_data;
  41         } else
  42                 init_special_inode(inode, inode->i_mode, huge_decode_dev(attr->va_rdev));
  43 }
  44
  45 static int coda_test_inode(struct inode *inode, void *data)
  46 {
  47         struct CodaFid *fid = (struct CodaFid *)data;
  48         return coda_fideq(&(ITOC(inode)->c_fid), fid);
  49 }
  50
  51 static int coda_set_inode(struct inode *inode, void *data)
  52 {
  53         struct CodaFid *fid = (struct CodaFid *)data;
  54         ITOC(inode)->c_fid = *fid;
  55         return 0;
  56 }
  57
  58 static int coda_fail_inode(struct inode *inode, void *data)
  59 {
  60         return -1;
  61 }
  62
  63 struct inode * coda_iget(struct super_block * sb, struct CodaFid * fid,
  64                          struct coda_vattr * attr)
  65 {
  66         struct inode *inode;
  67         struct coda_inode_info *cii;
  68         unsigned long hash = coda_f2i(fid);
  69
  70         inode = iget5_locked(sb, hash, coda_test_inode, coda_set_inode, fid);
  71
  72         if (!inode)
  73                 return ERR_PTR(-ENOMEM);
  74
  75         if (inode->i_state & I_NEW) {
  76                 cii = ITOC(inode);
  77                 /* we still need to set i_ino for things like stat(2) */
  78                 inode->i_ino = hash;
  79                 cii->c_mapcount = 0;
  80                 unlock_new_inode(inode);
  81         }
  82
  83         /* always replace the attributes, type might have changed */
  84         coda_fill_inode(inode, attr);
  85         return inode;
  86 }
  87
  88 /* this is effectively coda_iget:
  89    - get attributes (might be cached)
  90    - get the inode for the fid using vfs iget
  91    - link the two up if this is needed
  92    - fill in the attributes
  93 */
  94 int coda_cnode_make(struct inode **inode, struct CodaFid *fid, struct super_block *sb)
  95 {
  96         struct coda_vattr attr;
  97         int error;
  98
  99         /* We get inode numbers from Venus -- see venus source */
 100         error = venus_getattr(sb, fid, &attr);
 101         if ( error ) {
 102             *inode = NULL;
 103             return error;
 104         }
 105
 106         *inode = coda_iget(sb, fid, &attr);
 107         if ( IS_ERR(*inode) ) {
 108                 printk("coda_cnode_make: coda_iget failed\n");
 109                 return PTR_ERR(*inode);
 110         }
 111         return 0;
 112 }
 113
 114
 115 void coda_replace_fid(struct inode *inode, struct CodaFid *oldfid,
 116                       struct CodaFid *newfid)
 117 {
 118         struct coda_inode_info *cii;
 119         unsigned long hash = coda_f2i(newfid);
 120
 121         cii = ITOC(inode);
 122
 123         BUG_ON(!coda_fideq(&cii->c_fid, oldfid));
 124
 125         /* replace fid and rehash inode */
 126         /* XXX we probably need to hold some lock here! */
 127         remove_inode_hash(inode);
 128         cii->c_fid = *newfid;
 129         inode->i_ino = hash;
 130         __insert_inode_hash(inode, hash);
 131 }
 132
 133 /* convert a fid to an inode. */
 134 struct inode *coda_fid_to_inode(struct CodaFid *fid, struct super_block *sb)
 135 {
 136         struct inode *inode;
 137         unsigned long hash = coda_f2i(fid);
 138
 139         if ( !sb ) {
 140                 printk("coda_fid_to_inode: no sb!\n");
 141                 return NULL;
 142         }
 143
 144         inode = iget5_locked(sb, hash, coda_test_inode, coda_fail_inode, fid);
 145         if ( !inode )
 146                 return NULL;
 147
 148         /* we should never see newly created inodes because we intentionally
 149          * fail in the initialization callback */
 150         BUG_ON(inode->i_state & I_NEW);
 151
 152         return inode;
 153 }
 154
 155 /* the CONTROL inode is made without asking attributes from Venus */
 156 int coda_cnode_makectl(struct inode **inode, struct super_block *sb)
 157 {
 158         int error = -ENOMEM;
 159
 160         *inode = new_inode(sb);
 161         if (*inode) {
 162                 (*inode)->i_ino = CTL_INO;
 163                 (*inode)->i_op = &coda_ioctl_inode_operations;
 164                 (*inode)->i_fop = &coda_ioctl_operations;
 165                 (*inode)->i_mode = 0444;
 166                 error = 0;
 167         }
 168
 169         return error;
 170 }
 171