2 * Copyright 2000, International Business Machines Corporation and others.
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
11 /* osi_vm.c implements:
13 * osi_VM_FlushVCache(avc, slept)
14 * osi_ubc_flush_dirty_and_wait(vp, flags)
15 * osi_VM_StoreAllSegments(avc)
16 * osi_VM_TryToSmush(avc, acred, sync)
17 * osi_VM_FlushPages(avc, credp)
18 * osi_VM_Truncate(avc, alen, acred)
21 #include <afsconfig.h>
22 #include "../afs/param.h"
26 #include "../afs/sysincludes.h" /* Standard vendor system headers */
27 #include "../afs/afsincludes.h" /* Afs-based standard headers */
28 #include "../afs/afs_stats.h" /* statistics */
29 #include <vm/vm_object.h>
30 #include <vm/vm_map.h>
34 /* Try to discard pages, in order to recycle a vcache entry.
36 * We also make some sanity checks: ref count, open count, held locks.
38 * We also do some non-VM-related chores, such as releasing the cred pointer
39 * (for AIX and Solaris) and releasing the gnode (for AIX).
41 * Locking: afs_xvcache lock is held. If it is dropped and re-acquired,
42 * *slept should be set to warn the caller.
44 * Formerly, afs_xvcache was dropped and re-acquired for Solaris, but now it
45 * is not dropped and re-acquired for any platform. It may be that *slept is
46 * therefore obsolescent.
48 * OSF/1 Locking: VN_LOCK has been called.
51 osi_VM_FlushVCache(avc, slept)
55 struct vm_object *obj;
57 if (VREFCOUNT(avc) > 1)
63 /* if a lock is held, give up */
64 if (CheckLock(&avc->lock) || afs_CheckBozonLock(&avc->pvnLock))
69 simple_lock(&vp->v_interlock);
70 if (VOP_GETVOBJECT(vp, &obj) == 0) {
71 vm_object_page_remove(obj, 0, 0, FALSE);
73 if (obj->ref_count == 0) {
75 simple_lock(&vp->v_interlock);
81 simple_unlock(&vp->v_interlock);
87 /* Try to store pages to cache, in order to store a file back to the server.
89 * Locking: the vcache entry's lock is held. It will usually be dropped and
93 osi_VM_StoreAllSegments(avc)
97 struct vm_object *obj;
99 ReleaseWriteLock(&avc->lock);
105 simple_lock(&vp->v_interlock);
106 if (VOP_GETVOBJECT(vp, &obj) == 0 &&
107 (obj->flags & OBJ_MIGHTBEDIRTY)) {
109 LK_INTERLOCK | LK_EXCLUSIVE | LK_RETRY | LK_NOOBJ, curproc)) {
110 if (VOP_GETVOBJECT(vp, &obj) == 0) {
111 vm_object_page_clean(obj, 0, 0, OBJPC_SYNC);
117 simple_unlock(&vp->v_interlock);
119 } while (anyio && (--tries > 0));
121 ObtainWriteLock(&avc->lock,94);
124 /* Try to invalidate pages, for "fs flush" or "fs flushv"; or
125 * try to free pages, when deleting a file.
127 * Locking: the vcache entry's lock is held. It may be dropped and
130 * Since we drop and re-obtain the lock, we can't guarantee that there won't
131 * be some pages around when we return, newly created by concurrent activity.
134 osi_VM_TryToSmush(avc, acred, sync)
136 struct AFS_UCRED *acred;
140 struct vm_object *obj;
142 ReleaseWriteLock(&avc->lock);
148 simple_lock(&vp->v_interlock);
149 if (VOP_GETVOBJECT(vp, &obj) == 0 &&
150 (obj->flags & OBJ_MIGHTBEDIRTY)) {
152 LK_INTERLOCK | LK_EXCLUSIVE | LK_RETRY | LK_NOOBJ, curproc)) {
153 if (VOP_GETVOBJECT(vp, &obj) == 0) {
154 vm_object_page_clean(obj, 0, 0, OBJPC_SYNC);
160 simple_unlock(&vp->v_interlock);
162 } while (anyio && (--tries > 0));
163 simple_lock(&vp->v_interlock);
164 if (VOP_GETVOBJECT(vp, &obj) == 0) {
165 vm_object_page_remove(obj, 0, 0, FALSE);
167 simple_unlock(&vp->v_interlock);
168 /*vinvalbuf(AFSTOV(avc),0, NOCRED, curproc, 0,0);*/
170 ObtainWriteLock(&avc->lock,59);
173 /* Purge VM for a file when its callback is revoked.
175 * Locking: No lock is held, not even the global lock.
178 osi_VM_FlushPages(avc, credp)
180 struct AFS_UCRED *credp;
183 struct vm_object *obj;
185 simple_lock(&vp->v_interlock);
186 if (VOP_GETVOBJECT(vp, &obj) == 0) {
187 vm_object_page_remove(obj, 0, 0, FALSE);
189 simple_unlock(&vp->v_interlock);
190 /*vinvalbuf(AFSTOV(avc),0, NOCRED, curproc, 0,0);*/
193 /* Purge pages beyond end-of-file, when truncating a file.
195 * Locking: no lock is held, not even the global lock.
196 * activeV is raised. This is supposed to block pageins, but at present
197 * it only works on Solaris.
200 osi_VM_Truncate(avc, alen, acred)
203 struct AFS_UCRED *acred;
205 vnode_pager_setsize(AFSTOV(avc), alen);