src/afs/HPUX/osi_vm.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 #include <afsconfig.h>
  11 #include "afs/param.h"
  12
  13
  14 #include "afs/sysincludes.h"    /* Standard vendor system headers */
  15 #include "afsincludes.h"        /* Afs-based standard headers */
  16 #include "afs/afs_stats.h"      /* statistics */
  17
  18 /* Try to discard pages, in order to recycle a vcache entry.
  19  *
  20  * We also make some sanity checks:  ref count, open count, held locks.
  21  *
  22  * We also do some non-VM-related chores, such as releasing the cred pointer
  23  * (for AIX and Solaris) and releasing the gnode (for AIX).
  24  *
  25  * Locking:  afs_xvcache lock is held. It must not be dropped.
  26  */
  27 int
  28 osi_VM_FlushVCache(struct vcache *avc)
  29 {
  30     if (avc->vrefCount > 1)
  31         return EBUSY;
  32
  33     if (avc->opens)
  34         return EBUSY;
  35
  36     return 0;
  37 }
  38
  39 /* Try to store pages to cache, in order to store a file back to the server.
  40  *
  41  * Locking:  the vcache entry's lock is held.  It will usually be dropped and
  42  * re-obtained.
  43  */
  44 void
  45 osi_VM_StoreAllSegments(struct vcache *avc)
  46 {
  47     ;                           /* Nothing here yet */
  48 }
  49
  50 /* Try to invalidate pages, for "fs flush" or "fs flushv"; or
  51  * try to free pages, when deleting a file.
  52  *
  53  * Locking:  the vcache entry's lock is held.  It may be dropped and
  54  * re-obtained.
  55  */
  56 void
  57 osi_VM_TryToSmush(struct vcache *avc, afs_ucred_t *acred, int sync)
  58 {
  59     struct vnode *vp = AFSTOV(avc);
  60
  61     /* Flush the delayed write blocks associated with this vnode
  62      * from the buffer cache
  63      */
  64     if ((vp->v_flag & VTEXT) == 0) {
  65         mpurge(vp);
  66     }
  67     /* Mark the cached blocks on the free list as invalid; it invalidates blocks
  68      * associated with vp which are on the freelist.
  69      */
  70     binvalfree(vp);
  71     mpurge(vp);
  72 }
  73
  74 /* Purge VM for a file when its callback is revoked.
  75  *
  76  * Locking:  No lock is held, not even the global lock.
  77  */
  78 void
  79 osi_VM_FlushPages(struct vcache *avc, afs_ucred_t *credp)
  80 {
  81     ;                           /* Nothing here yet */
  82 }
  83
  84 /* Purge pages beyond end-of-file, when truncating a file.
  85  *
  86  * Locking:  no lock is held, not even the global lock.
  87  * activeV is raised.  This is supposed to block pageins, but at present
  88  * it only works on Solaris.
  89  */
  90 void
  91 osi_VM_Truncate(struct vcache *avc, int alen, afs_ucred_t *acred)
  92 {
  93     ;                           /* Nothing here yet */
  94 }