LXR linux/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
  14static inline int coda_fideq(struct CodaFid *fid1, struct CodaFid *fid2)
  15{
  16        return memcmp(fid1, fid2, sizeof(*fid1)) == 0;
  17}
  18
  19static 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 */
  27static 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
  45static 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
  51static 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
  58struct inode * coda_iget(struct super_block * sb, struct CodaFid * fid,
  59                         struct coda_vattr * attr)
  60{
  61        struct inode *inode;
  62        struct coda_inode_info *cii;
  63        unsigned long hash = coda_f2i(fid);
  64
  65        inode = iget5_locked(sb, hash, coda_test_inode, coda_set_inode, fid);
  66
  67        if (!inode)
  68                return ERR_PTR(-ENOMEM);
  69
  70        if (inode->i_state & I_NEW) {
  71                cii = ITOC(inode);
  72                /* we still need to set i_ino for things like stat(2) */
  73                inode->i_ino = hash;
  74                cii->c_mapcount = 0;
  75                unlock_new_inode(inode);
  76        }
  77
  78        /* always replace the attributes, type might have changed */
  79        coda_fill_inode(inode, attr);
  80        return inode;
  81}
  82
  83/* this is effectively coda_iget:
  84   - get attributes (might be cached)
  85   - get the inode for the fid using vfs iget
  86   - link the two up if this is needed
  87   - fill in the attributes
  88*/
  89int coda_cnode_make(struct inode **inode, struct CodaFid *fid, struct super_block *sb)
  90{
  91        struct coda_vattr attr;
  92        int error;
  93        
  94        /* We get inode numbers from Venus -- see venus source */
  95        error = venus_getattr(sb, fid, &attr);
  96        if ( error ) {
  97            *inode = NULL;
  98            return error;
  99        } 
 100
 101        *inode = coda_iget(sb, fid, &attr);
 102        if ( IS_ERR(*inode) ) {
 103                printk("coda_cnode_make: coda_iget failed\n");
 104                return PTR_ERR(*inode);
 105        }
 106        return 0;
 107}
 108
 109
 110void coda_replace_fid(struct inode *inode, struct CodaFid *oldfid, 
 111                      struct CodaFid *newfid)
 112{
 113        struct coda_inode_info *cii;
 114        unsigned long hash = coda_f2i(newfid);
 115        
 116        cii = ITOC(inode);
 117
 118        BUG_ON(!coda_fideq(&cii->c_fid, oldfid));
 119
 120        /* replace fid and rehash inode */
 121        /* XXX we probably need to hold some lock here! */
 122        remove_inode_hash(inode);
 123        cii->c_fid = *newfid;
 124        inode->i_ino = hash;
 125        __insert_inode_hash(inode, hash);
 126}
 127
 128/* convert a fid to an inode. */
 129struct inode *coda_fid_to_inode(struct CodaFid *fid, struct super_block *sb) 
 130{
 131        struct inode *inode;
 132        unsigned long hash = coda_f2i(fid);
 133
 134        if ( !sb ) {
 135                printk("coda_fid_to_inode: no sb!\n");
 136                return NULL;
 137        }
 138
 139        inode = ilookup5(sb, hash, coda_test_inode, fid);
 140        if ( !inode )
 141                return NULL;
 142
 143        /* we should never see newly created inodes because we intentionally
 144         * fail in the initialization callback */
 145        BUG_ON(inode->i_state & I_NEW);
 146
 147        return inode;
 148}
 149
 150/* the CONTROL inode is made without asking attributes from Venus */
 151int coda_cnode_makectl(struct inode **inode, struct super_block *sb)
 152{
 153        int error = -ENOMEM;
 154
 155        *inode = new_inode(sb);
 156        if (*inode) {
 157                (*inode)->i_ino = CTL_INO;
 158                (*inode)->i_op = &coda_ioctl_inode_operations;
 159                (*inode)->i_fop = &coda_ioctl_operations;
 160                (*inode)->i_mode = 0444;
 161                error = 0;
 162        }
 163
 164        return error;
 165}
 166
 167