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
10 #include <afsconfig.h>
11 #include "../afs/param.h"
15 #include "../afs/sysincludes.h" /* Standard vendor system headers */
16 #include "../afs/afsincludes.h" /* Afs-based standard headers */
17 #include "../afs/afs_stats.h" /* statistics */
18 #include "sys/flock.h" /* for IGN_PID */
20 extern struct vnodeops Afs_vnodeops;
22 /* Try to discard pages, in order to recycle a vcache entry.
24 * We also make some sanity checks: ref count, open count, held locks.
26 * We also do some non-VM-related chores, such as releasing the cred pointer
27 * (for AIX and Solaris) and releasing the gnode (for AIX).
29 * Locking: afs_xvcache lock is held. If it is dropped and re-acquired,
30 * *slept should be set to warn the caller.
32 * Formerly, afs_xvcache was dropped and re-acquired for Solaris, but now it
33 * is not dropped and re-acquired for any platform. It may be that *slept is
34 * therefore obsolescent.
36 int osi_VM_FlushVCache(struct vcache *avc, int *slept)
39 vnode_t *vp = &avc->v;
41 if (avc->vrefCount != 0)
48 * Just in case someone is still referring to the vnode we give up
49 * trying to get rid of this guy.
51 if (CheckLock(&avc->lock) || LockWaiters(&avc->lock))
57 * we just need to avoid the race
58 * in vn_rele between the ref count going to 0 and VOP_INACTIVE
60 * Note that although we checked vcount above, we didn't have the lock
62 if (vp->v_count > 0 || (vp->v_flag & VINACT)) {
69 * Since we store on last close and on VOP_INACTIVE
70 * there should be NO dirty pages
71 * Note that we hold the xvcache lock the entire time.
74 PTOSSVP(vp, (off_t)0, (off_t)MAXLONG);
77 /* afs_chkpgoob will drop and re-acquire the global lock. */
79 osi_Assert(!VN_GET_PGCNT(vp));
80 osi_Assert(!AFS_VN_MAPPED(vp));
81 osi_Assert(!AFS_VN_DIRTY(&avc->v));
83 #if defined(AFS_SGI65_ENV)
85 cleanlocks(vp, IGN_PID, 0);
86 mutex_destroy(&vp->v_filocksem);
87 #else /* AFS_SGI65_ENV */
88 if (vp->v_filocksem) {
91 cleanlocks(vp, &curprocp->p_flid);
93 cleanlocks(vp, IGN_PID, 0);
95 osi_Assert(vp->v_filocks == NULL);
96 mutex_destroy(vp->v_filocksem);
97 kmem_free(vp->v_filocksem, sizeof *vp->v_filocksem);
98 vp->v_filocksem = NULL;
100 #endif /* AFS_SGI65_ENV */
102 if (avc->vrefCount) osi_Panic("flushVcache: vm race");
105 vnode_pcache_reclaim(vp); /* this can sleep */
106 vnode_pcache_free(vp);
107 if (vp->v_op != &Afs_vnodeops) {
108 VOP_RECLAIM(vp, FSYNC_WAIT, code);
113 ktrace_free(vp->v_trace);
114 #endif /* VNODE_TRACING */
115 vn_bhv_remove(VN_BHV_HEAD(vp), &(avc->vc_bhv_desc));
116 vn_bhv_head_destroy(&(vp->v_bh));
117 destroy_bitlock(&vp->v_pcacheflag);
118 mutex_destroy(&vp->v_buf_lock);
120 bhv_remove(VN_BHV_HEAD(vp), &(avc->vc_bhv_desc));
121 bhv_head_destroy(&(vp->v_bh));
123 vp->v_flag = 0; /* debug */
124 #if defined(DEBUG) && defined(VNODE_INIT_BITLOCK)
125 destroy_bitlock(&vp->v_flag);
128 AFS_VN_DESTROY_BUF_LOCK(vp);
130 #endif /* AFS_SGI64_ENV */
135 /* Try to invalidate pages, for "fs flush" or "fs flushv"; or
136 * try to free pages, when deleting a file.
138 * Locking: the vcache entry's lock is held. It may be dropped and
141 * Since we drop and re-obtain the lock, we can't guarantee that there won't
142 * be some pages around when we return, newly created by concurrent activity.
144 void osi_VM_TryToSmush(struct vcache *avc, struct AFS_UCRED *acred, int sync)
146 ReleaseWriteLock(&avc->lock);
148 /* current remapf restriction - cannot have VOP_RWLOCK */
149 osi_Assert(OSI_GET_LOCKID() != avc->vc_rwlockid);
150 if (((vnode_t *)avc)->v_type == VREG && AFS_VN_MAPPED(((vnode_t *)avc)))
151 remapf(((vnode_t *)avc), 0, 0);
152 PTOSSVP(AFSTOV(avc), (off_t)0, (off_t)MAXLONG);
154 ObtainWriteLock(&avc->lock,62);
157 /* Flush and invalidate pages, for fsync() with INVAL flag
159 * Locking: only the global lock is held.
161 void osi_VM_FSyncInval(struct vcache *avc)
164 PFLUSHINVALVP((vnode_t *)avc, (off_t)0, (off_t)avc->m.Length);
168 /* Try to store pages to cache, in order to store a file back to the server.
170 * Locking: the vcache entry's lock is held. It will usually be dropped and
173 void osi_VM_StoreAllSegments(struct vcache *avc)
176 osi_Assert(valusema(&avc->vc_rwlock) <= 0);
177 osi_Assert(OSI_GET_LOCKID() == avc->vc_rwlockid);
178 osi_Assert(avc->vrefCount > 0);
179 ReleaseWriteLock(&avc->lock);
180 /* We may call back into AFS via:
181 * pflushvp->chunkpush->do_pdflush->mp_afs_bmap
185 /* Write out dirty pages list to avoid B_DELWRI buffers. */
186 while (VN_GET_DPAGES((vnode_t*)avc)) {
187 pdflush(AFSTOV(avc), 0);
190 PFLUSHVP(AFSTOV(avc), (off_t)avc->m.Length, (off_t)0, error);
194 * If this fails (due to quota overage, etc.)
195 * what can we do?? we need to sure that
196 * that the VM cache is cleared of dirty pages
197 * We note that pinvalfree ignores write errors & otherwise
198 * does what we want (we don't use this normally since
199 * it also unhashes pages ..)
201 PINVALFREE((vnode_t *)avc, avc->m.Length);
203 ObtainWriteLock(&avc->lock,121);
204 if (error && avc->m.LinkCount)
205 cmn_err(CE_WARN, "AFS:Failed to push back pages for vnode 0x%x error %d (from afs_StoreOnLastReference)",
209 /* Purge VM for a file when its callback is revoked.
211 * Locking: No lock is held, not even the global lock.
213 void osi_VM_FlushPages(struct vcache *avc, struct AFS_UCRED *credp)
215 vnode_t *vp = (vnode_t *)avc;
217 remapf(vp, /*avc->m.Length*/ 0, 0);
219 /* Used to grab locks and recheck avc->m.DataVersion and
220 * avc->execsOrWriters here, but we have to drop locks before calling
221 * ptossvp() anyway, so why bother.
225 * ptossvp tosses all pages associated with this vnode
226 * All in-use pages are marked BAD
228 PTOSSVP(vp, (off_t)0, (off_t)MAXLONG);
231 /* Purge pages beyond end-of-file, when truncating a file.
233 * Locking: no lock is held, not even the global lock.
234 * activeV is raised. This is supposed to block pageins, but at present
235 * it only works on Solaris.
237 void osi_VM_Truncate(struct vcache *avc, int alen, struct AFS_UCRED *acred)
239 PTOSSVP(&avc->v, (off_t)alen, (off_t)MAXLONG);