src/afs/VNOPS/afs_vnop_strategy.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_ustrategy
  13  */
  14
  15 #include <afsconfig.h>
  16 #include "afs/param.h"
  17
  18
  19 #if !defined(AFS_HPUX_ENV) && !defined(AFS_SGI_ENV) && !defined(AFS_LINUX20_ENV) && !defined(AFS_DARWIN80_ENV)
  20
  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 #if defined(AFS_SUN5_ENV) || defined(AFS_DARWIN_ENV) || defined(AFS_XBSD_ENV)
  31 int afs_ustrategy(struct buf *abp, afs_ucred_t *credp)
  32 #else
  33 int afs_ustrategy(struct buf *abp)
  34 #endif
  35 {
  36     afs_int32 code;
  37     struct uio tuio;
  38     struct iovec tiovec[1];
  39     struct vcache *tvc = VTOAFS(abp->b_vp);
  40     afs_int32 len = abp->b_bcount;
  41 #ifdef  AFS_AIX41_ENV
  42     struct ucred *credp;
  43 #elif defined(UKERNEL)
  44     afs_ucred_t *credp = get_user_struct()->u_cred;
  45 #elif !defined(AFS_SUN5_ENV) && !defined(AFS_DARWIN_ENV) && !defined(AFS_XBSD_ENV)
  46     afs_ucred_t *credp = u.u_cred;
  47 #endif
  48
  49     memset(&tuio, 0, sizeof(tuio));
  50     memset(&tiovec, 0, sizeof(tiovec));
  51
  52     AFS_STATCNT(afs_ustrategy);
  53 #ifdef  AFS_AIX41_ENV
  54     /*
  55      * So that it won't change while reading it
  56      */
  57     ObtainReadLock(&tvc->lock);
  58     if (tvc->credp) {
  59         credp = tvc->credp;
  60         crhold(credp);
  61     } else {
  62         credp = crref();
  63     }
  64     ReleaseReadLock(&tvc->lock);
  65     osi_Assert(credp);
  66 #endif
  67 #ifdef AFS_FBSD_ENV
  68     if (abp->b_iocmd == BIO_READ) {
  69 #else
  70     if ((abp->b_flags & B_READ) == B_READ) {
  71 #endif
  72         /* read b_bcount bytes into kernel address b_un.b_addr starting
  73          * at byte DEV_BSIZE * b_blkno.  Bzero anything we can't read,
  74          * and finally call iodone(abp).  File is in abp->b_vp.  Credentials
  75          * are from u area??
  76          */
  77         tuio.afsio_iov = tiovec;
  78         tuio.afsio_iovcnt = 1;
  79 #if defined(AFS_SUN5_ENV) || defined(AFS_XBSD_ENV)
  80 # ifdef AFS_64BIT_CLIENT
  81 #  ifdef AFS_SUN5_ENV
  82         tuio.afsio_offset = (afs_offs_t) ldbtob(abp->b_lblkno);
  83 #  else
  84         tuio.afsio_offset = (afs_offs_t) dbtob(abp->b_blkno);
  85 #  endif
  86 # else /* AFS_64BIT_CLIENT */
  87         tuio.afsio_offset = (u_int) dbtob(abp->b_blkno);
  88 # endif /* AFS_64BIT_CLIENT */
  89 #else
  90         tuio.afsio_offset = DEV_BSIZE * abp->b_blkno;
  91 #endif
  92 #if defined(AFS_NBSD40_ENV)
  93         UIO_SETUP_SYSSPACE(&tuio);
  94 #else
  95         tuio.afsio_seg = AFS_UIOSYS;
  96 #endif
  97 #ifdef AFS_UIOFMODE
  98         tuio.afsio_fmode = 0;
  99 #endif
 100         tuio.afsio_resid = abp->b_bcount;
 101 #if defined(AFS_NBSD40_ENV) || defined(FBSD_STRUCT_BUF_NO_SAVEADDR)
 102         tiovec[0].iov_base = abp->b_data;
 103 #elif defined(AFS_XBSD_ENV)
 104         tiovec[0].iov_base = abp->b_saveaddr;
 105 #else
 106         tiovec[0].iov_base = abp->b_un.b_addr;
 107 #endif /* AFS_XBSD_ENV */
 108         tiovec[0].iov_len = abp->b_bcount;
 109         /* are user's credentials valid here?  probably, but this
 110          * sure seems like the wrong things to do. */
 111 #if     defined(AFS_SUN5_ENV)
 112         code = afs_nlrdwr(VTOAFS(abp->b_vp), &tuio, UIO_READ, 0, credp);
 113 #else
 114         code = afs_rdwr(VTOAFS(abp->b_vp), &tuio, UIO_READ, 0, credp);
 115 #endif
 116         if (code == 0) {
 117             if (tuio.afsio_resid > 0)
 118 #if defined(AFS_NBSD40_ENV) || defined(FBSD_STRUCT_BUF_NO_SAVEADDR)
 119                 memset((char *)abp->b_data + (uintptr_t)abp->b_bcount - tuio.afsio_resid, 0,
 120                        tuio.afsio_resid);
 121 #elif defined(AFS_XBSD_ENV)
 122                 memset(abp->b_saveaddr + abp->b_bcount - tuio.afsio_resid, 0,
 123                        tuio.afsio_resid);
 124 #else
 125                 memset(abp->b_un.b_addr + abp->b_bcount - tuio.afsio_resid, 0,
 126                        tuio.afsio_resid);
 127 #endif /* AFS_XBSD_ENV */
 128 #ifdef  AFS_AIX32_ENV
 129             /*
 130              * If we read a block that is past EOF and the user was not storing
 131              * to it, go ahead and write protect the page. This way we will detect
 132              * storing beyond EOF in the future
 133              */
 134             if (dbtob(abp->b_blkno) + abp->b_bcount > tvc->f.m.Length) {
 135                 if ((abp->b_flags & B_PFSTORE) == 0) {
 136                     AFS_GUNLOCK();
 137                     vm_protectp(tvc->segid, dbtob(abp->b_blkno) / PAGESIZE,
 138                                 abp->b_bcount / PAGESIZE, RDONLY);
 139                     AFS_GLOCK();
 140                 }
 141             }
 142 #endif
 143         }
 144     } else {
 145         tuio.afsio_iov = tiovec;
 146         tuio.afsio_iovcnt = 1;
 147 #if defined(AFS_SUN5_ENV)
 148 #ifdef AFS_64BIT_CLIENT
 149 #ifdef AFS_SUN5_ENV
 150         tuio.afsio_offset = (afs_offs_t) ldbtob(abp->b_lblkno);
 151 #else
 152         tuio.afsio_offset = (afs_offs_t) dbtob(abp->b_blkno);
 153 #endif
 154 #else /* AFS_64BIT_CLIENT */
 155         tuio.afsio_offset = (u_int) dbtob(abp->b_blkno);
 156 #endif /* AFS_64BIT_CLIENT */
 157 #ifdef  AFS_SUN5_ENV
 158 #ifdef  AFS_SUN59_ENV
 159         tuio.uio_limit = curproc->p_fsz_ctl.rlim_cur;
 160 #else
 161         tuio.uio_limit = u.u_rlimit[RLIMIT_FSIZE].rlim_cur;
 162 #endif
 163 #endif
 164 #else
 165         tuio.afsio_offset = DEV_BSIZE * abp->b_blkno;
 166 #endif
 167 #if defined(AFS_NBSD40_ENV)
 168         UIO_SETUP_SYSSPACE(&tuio);
 169 #else
 170         tuio.afsio_seg = AFS_UIOSYS;
 171 #endif
 172 #ifdef AFS_UIOFMODE
 173         tuio.afsio_fmode = 0;
 174 #endif
 175 #ifdef  AFS_AIX32_ENV
 176         /*
 177          * XXX It this really right? Ideally we should always write block size multiple
 178          * and not any arbitrary size, right? XXX
 179          */
 180         len = MIN(len, tvc->f.m.Length - dbtob(abp->b_blkno));
 181 #endif
 182         tuio.afsio_resid = len;
 183 #if defined(AFS_NBSD40_ENV) || defined(FBSD_STRUCT_BUF_NO_SAVEADDR)
 184         tiovec[0].iov_base = abp->b_data;
 185 #elif defined(AFS_XBSD_ENV)
 186         tiovec[0].iov_base = abp->b_saveaddr;
 187 #else
 188         tiovec[0].iov_base = abp->b_un.b_addr;
 189 #endif /* AFS_XBSD_ENV */
 190         tiovec[0].iov_len = len;
 191         /* are user's credentials valid here?  probably, but this
 192          * sure seems like the wrong things to do. */
 193 #if     defined(AFS_SUN5_ENV)
 194         code = afs_nlrdwr(VTOAFS(abp->b_vp), &tuio, UIO_WRITE, 0, credp);
 195 #else
 196         code = afs_rdwr(VTOAFS(abp->b_vp), &tuio, UIO_WRITE, 0, credp);
 197 #endif
 198     }
 199
 200 #if defined (AFS_XBSD_ENV)
 201     if (code) {
 202         abp->b_error = code;
 203 #if !defined(AFS_FBSD_ENV) && !defined(AFS_NBSD50_ENV)
 204         abp->b_flags |= B_ERROR;
 205 #endif
 206     }
 207 #endif
 208
 209 #if defined(AFS_AIX32_ENV)
 210     crfree(credp);
 211 #elif defined(AFS_FBSD60_ENV)
 212     (*abp->b_iodone)(abp);
 213 #elif defined(AFS_FBSD_ENV)
 214     biodone(&abp->b_io);
 215 #elif defined(AFS_NBSD40_ENV)
 216     abp->b_resid = tuio.uio_resid;
 217     biodone(abp);
 218 #elif defined(AFS_XBSD_ENV)
 219     biodone(abp);
 220 #elif !defined(AFS_SUN5_ENV)
 221     iodone(abp);
 222 #endif
 223
 224     afs_Trace3(afs_iclSetp, CM_TRACE_STRATEGYDONE, ICL_TYPE_POINTER, tvc,
 225                ICL_TYPE_INT32, code, ICL_TYPE_LONG, tuio.afsio_resid);
 226     return code;
 227 }
 228
 229 #endif /* !AFS_HPUX_ENV  && !AFS_SGI_ENV && !AFS_LINUX20_ENV */