src/afs/VNOPS/afs_vnop_fid.c

   1 /*
   2  * Copyright 2000, International Business Machines Corporation and others.
   3  * All Rights Reserved.
   4  *
   5  * This software has been released under the terms of the IBM Public
   6  * License.  For details, see the LICENSE file in the top-level source
   7  * directory or online at http://www.openafs.org/dl/license10.html
   8  */
   9
  10 /*
  11  * Implements:
  12  * afs_fid
  13  *
  14  */
  15
  16 #include <afsconfig.h>
  17 #include "afs/param.h"
  18
  19
  20 #if !defined(AFS_LINUX20_ENV) && !defined(AFS_DARWIN_ENV) && !defined(AFS_OBSD_ENV) && !defined(AFS_NBSD_ENV)
  21 #include "afs/sysincludes.h"    /* Standard vendor system headers */
  22 #include "afsincludes.h"        /* Afs-based standard headers */
  23 #include "afs/afs_stats.h"      /* statistics */
  24 #include "afs/afs_cbqueue.h"
  25 #include "afs/nfsclient.h"
  26 #include "afs/afs_osidnlc.h"
  27
  28
  29
  30 int afs_fid_vnodeoverflow = 0, afs_fid_uniqueoverflow = 0;
  31
  32 /*
  33  *  afs_fid
  34  *
  35  * afs_fid can return two flavors of NFS fid, depending on if submounts are
  36  * allowed. The reason for this is that we can't guarantee that we found all
  37  * the entry points any OS might use to get the fid for the NFS mountd.
  38  * Hence we return a "magic" fid for all but /afs. If it goes through the
  39  * translator code, it will get transformed into a SmallFid that we recognize.
  40  * So, if submounts are disallowed, and an NFS client tries a submount, it will
  41  * get a fid which we don't recognize and the mount will either fail or we
  42  * will ignore subsequent requests for that mount.
  43  *
  44  * The Alpha fid is organized differently than for other platforms. Their
  45  * intention was to have the data portion of the fid aligned on a 4 byte
  46  * boundary. To do so, the fid is organized as:
  47  * u_short reserved
  48  * u_short len
  49  * char data[8]
  50  * The len field is the length of the entire fid, from reserved through data.
  51  * This length is used by fid_copy to include copying the reserved field.
  52  * Alpha's zero the reserved field before handing us the fid, but they use
  53  * it in fid_cmp. We use the reserved field to store the 16 bits of the Vnode.
  54  *
  55  * Note that the SmallFid only allows for 8 bits of the cell index and
  56  * 16 bits of the vnode.
  57  */
  58
  59 #ifdef AFS_AIX41_ENV
  60 int afs_iauth_initd = 0;
  61 #define USE_SMALLFID(C) (afs_iauth_initd && AFS_NFSXLATORREQ(C))
  62 #endif
  63
  64
  65 extern int afs_NFSRootOnly;     /* 1 => only allow NFS mounts of /afs. */
  66
  67 int
  68 #ifdef AFS_AIX41_ENV
  69 afs_fid(OSI_VC_DECL(avc), struct fid *fidpp, struct ucred *credp)
  70 #elif defined(AFS_SUN5_ENV)
  71 afs_fid(OSI_VC_DECL(avc), struct fid *fidpp)
  72 #else
  73 afs_fid(OSI_VC_DECL(avc), struct fid **fidpp)
  74 #endif                          /* AFS_AIX41_ENV */
  75 {
  76     struct SmallFid Sfid;
  77     long addr[2];
  78     struct cell *tcell;
  79     extern struct vcache *afs_globalVp;
  80     int SizeOfSmallFid = SIZEOF_SMALLFID;
  81     int rootvp = 0;
  82     OSI_VC_CONVERT(avc);
  83
  84     AFS_STATCNT(afs_fid);
  85
  86     if (afs_shuttingdown != AFS_RUNNING)
  87         return EIO;
  88
  89     if (afs_NFSRootOnly && (avc == afs_globalVp))
  90         rootvp = 1;
  91     if (!afs_NFSRootOnly || rootvp
  92 #ifdef AFS_AIX41_ENV
  93         || USE_SMALLFID(credp)
  94 #endif
  95         ) {
  96         tcell = afs_GetCell(avc->f.fid.Cell, READ_LOCK);
  97         Sfid.Volume = avc->f.fid.Fid.Volume;
  98         Sfid.Vnode = avc->f.fid.Fid.Vnode;
  99         Sfid.CellAndUnique =
 100             ((tcell->cellIndex << 24) + (avc->f.fid.Fid.Unique & 0xffffff));
 101         afs_PutCell(tcell, READ_LOCK);
 102         if (avc->f.fid.Fid.Vnode > 0xffff)
 103             afs_fid_vnodeoverflow++;
 104         if (avc->f.fid.Fid.Unique > 0xffffff)
 105             afs_fid_uniqueoverflow++;
 106     } else {
 107 #if defined(AFS_SUN5_64BIT_ENV) || (defined(AFS_SGI61_ENV) && (_MIPS_SZPTR == 64))
 108         addr[1] = (long)AFS_XLATOR_MAGIC << 48;
 109 #else /* defined(AFS_SGI61_ENV) && (_MIPS_SZPTR == 64) */
 110         addr[1] = AFS_XLATOR_MAGIC;
 111         SizeOfSmallFid = sizeof(addr);
 112 #endif /* defined(AFS_SGI61_ENV) && (_MIPS_SZPTR == 64) */
 113         addr[0] = (long)avc;
 114 #ifndef AFS_AIX41_ENV
 115         /* No post processing, so don't hold ref count. */
 116         AFS_FAST_HOLD(avc);
 117 #endif
 118     }
 119 #if     defined(AFS_AIX_ENV) || defined(AFS_SUN5_ENV)
 120     /* Use the fid pointer passed to us. */
 121     fidpp->fid_len = SizeOfSmallFid;
 122
 123     if (afs_NFSRootOnly) {
 124         if (rootvp
 125 #ifdef AFS_AIX41_ENV
 126             || USE_SMALLFID(credp)
 127 #endif
 128             ) {
 129             memcpy(fidpp->fid_data, (caddr_t) & Sfid, SizeOfSmallFid);
 130         } else {
 131             memcpy(fidpp->fid_data, (caddr_t) addr, SizeOfSmallFid);
 132         }
 133     } else {
 134         memcpy(fidpp->fid_data, (caddr_t) & Sfid, SizeOfSmallFid);
 135     }
 136 #else
 137     /* malloc a fid pointer ourselves. */
 138     *fidpp = (struct fid *)AFS_KALLOC(SizeOfSmallFid + 2);
 139     (*fidpp)->fid_len = SizeOfSmallFid;
 140     if (afs_NFSRootOnly) {
 141         if (rootvp) {
 142             memcpy((*fidpp)->fid_data, (char *)&Sfid, SizeOfSmallFid);
 143         } else {
 144             memcpy((*fidpp)->fid_data, (char *)addr, SizeOfSmallFid);
 145         }
 146     } else {
 147         memcpy((*fidpp)->fid_data, (char *)&Sfid, SizeOfSmallFid);
 148     }
 149 #endif
 150     return (0);
 151 }
 152
 153
 154 #endif /* !AFS_LINUX20_ENV */