fs/nfsd/nfsfh.h

   1 /* Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de> */
   2
   3 #ifndef _LINUX_NFSD_FH_INT_H
   4 #define _LINUX_NFSD_FH_INT_H
   5
   6 #include <linux/nfsd/nfsfh.h>
   7
   8 enum nfsd_fsid {
   9         FSID_DEV = 0,
  10         FSID_NUM,
  11         FSID_MAJOR_MINOR,
  12         FSID_ENCODE_DEV,
  13         FSID_UUID4_INUM,
  14         FSID_UUID8,
  15         FSID_UUID16,
  16         FSID_UUID16_INUM,
  17 };
  18
  19 enum fsid_source {
  20         FSIDSOURCE_DEV,
  21         FSIDSOURCE_FSID,
  22         FSIDSOURCE_UUID,
  23 };
  24 extern enum fsid_source fsid_source(struct svc_fh *fhp);
  25
  26
  27 /* This might look a little large to "inline" but in all calls except
  28  * one, 'vers' is constant so moste of the function disappears.
  29  */
  30 static inline void mk_fsid(int vers, u32 *fsidv, dev_t dev, ino_t ino,
  31                            u32 fsid, unsigned char *uuid)
  32 {
  33         u32 *up;
  34         switch(vers) {
  35         case FSID_DEV:
  36                 fsidv[0] = htonl((MAJOR(dev)<<16) |
  37                                  MINOR(dev));
  38                 fsidv[1] = ino_t_to_u32(ino);
  39                 break;
  40         case FSID_NUM:
  41                 fsidv[0] = fsid;
  42                 break;
  43         case FSID_MAJOR_MINOR:
  44                 fsidv[0] = htonl(MAJOR(dev));
  45                 fsidv[1] = htonl(MINOR(dev));
  46                 fsidv[2] = ino_t_to_u32(ino);
  47                 break;
  48
  49         case FSID_ENCODE_DEV:
  50                 fsidv[0] = new_encode_dev(dev);
  51                 fsidv[1] = ino_t_to_u32(ino);
  52                 break;
  53
  54         case FSID_UUID4_INUM:
  55                 /* 4 byte fsid and inode number */
  56                 up = (u32*)uuid;
  57                 fsidv[0] = ino_t_to_u32(ino);
  58                 fsidv[1] = up[0] ^ up[1] ^ up[2] ^ up[3];
  59                 break;
  60
  61         case FSID_UUID8:
  62                 /* 8 byte fsid  */
  63                 up = (u32*)uuid;
  64                 fsidv[0] = up[0] ^ up[2];
  65                 fsidv[1] = up[1] ^ up[3];
  66                 break;
  67
  68         case FSID_UUID16:
  69                 /* 16 byte fsid - NFSv3+ only */
  70                 memcpy(fsidv, uuid, 16);
  71                 break;
  72
  73         case FSID_UUID16_INUM:
  74                 /* 8 byte inode and 16 byte fsid */
  75                 *(u64*)fsidv = (u64)ino;
  76                 memcpy(fsidv+2, uuid, 16);
  77                 break;
  78         default: BUG();
  79         }
  80 }
  81
  82 static inline int key_len(int type)
  83 {
  84         switch(type) {
  85         case FSID_DEV:          return 8;
  86         case FSID_NUM:          return 4;
  87         case FSID_MAJOR_MINOR:  return 12;
  88         case FSID_ENCODE_DEV:   return 8;
  89         case FSID_UUID4_INUM:   return 8;
  90         case FSID_UUID8:        return 8;
  91         case FSID_UUID16:       return 16;
  92         case FSID_UUID16_INUM:  return 24;
  93         default: return 0;
  94         }
  95 }
  96
  97 /*
  98  * Shorthand for dprintk()'s
  99  */
 100 extern char * SVCFH_fmt(struct svc_fh *fhp);
 101
 102 /*
 103  * Function prototypes
 104  */
 105 __be32  fh_verify(struct svc_rqst *, struct svc_fh *, umode_t, int);
 106 __be32  fh_compose(struct svc_fh *, struct svc_export *, struct dentry *, struct svc_fh *);
 107 __be32  fh_update(struct svc_fh *);
 108 void    fh_put(struct svc_fh *);
 109
 110 static __inline__ struct svc_fh *
 111 fh_copy(struct svc_fh *dst, struct svc_fh *src)
 112 {
 113         WARN_ON(src->fh_dentry || src->fh_locked);
 114
 115         *dst = *src;
 116         return dst;
 117 }
 118
 119 static inline void
 120 fh_copy_shallow(struct knfsd_fh *dst, struct knfsd_fh *src)
 121 {
 122         dst->fh_size = src->fh_size;
 123         memcpy(&dst->fh_base, &src->fh_base, src->fh_size);
 124 }
 125
 126 static __inline__ struct svc_fh *
 127 fh_init(struct svc_fh *fhp, int maxsize)
 128 {
 129         memset(fhp, 0, sizeof(*fhp));
 130         fhp->fh_maxsize = maxsize;
 131         return fhp;
 132 }
 133
 134 #ifdef CONFIG_NFSD_V3
 135 /*
 136  * Fill in the pre_op attr for the wcc data
 137  */
 138 static inline void
 139 fill_pre_wcc(struct svc_fh *fhp)
 140 {
 141         struct inode    *inode;
 142
 143         inode = fhp->fh_dentry->d_inode;
 144         if (!fhp->fh_pre_saved) {
 145                 fhp->fh_pre_mtime = inode->i_mtime;
 146                 fhp->fh_pre_ctime = inode->i_ctime;
 147                 fhp->fh_pre_size  = inode->i_size;
 148                 fhp->fh_pre_change = inode->i_version;
 149                 fhp->fh_pre_saved = 1;
 150         }
 151 }
 152
 153 extern void fill_post_wcc(struct svc_fh *);
 154 #else
 155 #define fill_pre_wcc(ignored)
 156 #define fill_post_wcc(notused)
 157 #endif /* CONFIG_NFSD_V3 */
 158
 159
 160 /*
 161  * Lock a file handle/inode
 162  * NOTE: both fh_lock and fh_unlock are done "by hand" in
 163  * vfs.c:nfsd_rename as it needs to grab 2 i_mutex's at once
 164  * so, any changes here should be reflected there.
 165  */
 166
 167 static inline void
 168 fh_lock_nested(struct svc_fh *fhp, unsigned int subclass)
 169 {
 170         struct dentry   *dentry = fhp->fh_dentry;
 171         struct inode    *inode;
 172
 173         BUG_ON(!dentry);
 174
 175         if (fhp->fh_locked) {
 176                 printk(KERN_WARNING "fh_lock: %pd2 already locked!\n",
 177                         dentry);
 178                 return;
 179         }
 180
 181         inode = dentry->d_inode;
 182         mutex_lock_nested(&inode->i_mutex, subclass);
 183         fill_pre_wcc(fhp);
 184         fhp->fh_locked = 1;
 185 }
 186
 187 static inline void
 188 fh_lock(struct svc_fh *fhp)
 189 {
 190         fh_lock_nested(fhp, I_MUTEX_NORMAL);
 191 }
 192
 193 /*
 194  * Unlock a file handle/inode
 195  */
 196 static inline void
 197 fh_unlock(struct svc_fh *fhp)
 198 {
 199         if (fhp->fh_locked) {
 200                 fill_post_wcc(fhp);
 201                 mutex_unlock(&fhp->fh_dentry->d_inode->i_mutex);
 202                 fhp->fh_locked = 0;
 203         }
 204 }
 205
 206 #endif /* _LINUX_NFSD_FH_INT_H */