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"
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 #include "afs/nfsclient.h"
19 /* This file contains Solaris VM-related code for the cache manager. */
27 #include <vm/seg_map.h>
28 #include <vm/seg_vn.h>
30 #include <sys/modctl.h>
31 #include <sys/syscall.h>
32 #include <sys/debug.h>
33 #include <sys/fs_subr.h>
35 /* Try to invalidate pages, in order to recycle a dcache entry.
37 * This function only exists for Solaris. For other platforms, it's OK to
38 * recycle a dcache entry without invalidating pages, because the strategy
39 * function can call afs_GetDCache().
41 * Locking: only the global lock is held on entry.
44 osi_VM_GetDownD(struct vcache *avc, struct dcache *adc)
50 afs_putpage(AFSTOV(avc), (offset_t) AFS_CHUNKTOBASE(adc->f.chunk),
51 AFS_CHUNKTOSIZE(adc->f.chunk), B_INVAL, CRED());
57 /* Does this dcache conflict with a multiPage request for this vcache?
59 * This function only exists for Solaris. This is used by afs_GetDownD to
60 * calculate if trying to evict the given dcache may deadlock with an
61 * in-progress afs_getpage call that is trying to get more than one page at
62 * once. See afs_getpage for details. We return 0 if we do NOT conflict,
63 * nonzero otherwise. If we return nonzero, we should NOT try to evict the
64 * given dcache entry from the cache.
66 * Locking: tvc->vlock is write-locked on entry (and GLOCK is held)
69 osi_VM_MultiPageConflict(struct vcache *avc, struct dcache *adc)
71 struct multiPage_range *range;
72 for (range = (struct multiPage_range *)avc->multiPage.next;
73 range != &avc->multiPage;
74 range = (struct multiPage_range *)QNext(&range->q)) {
76 if (adc->f.chunk >= AFS_CHUNK(range->off) &&
77 adc->f.chunk <= AFS_CHUNK(range->off + range->len - 1)) {
85 /* Try to discard pages, in order to recycle a vcache entry.
87 * We also make some sanity checks: ref count, open count, held locks.
89 * We also do some non-VM-related chores, such as releasing the cred pointer
90 * (for AIX and Solaris) and releasing the gnode (for AIX).
92 * Locking: afs_xvcache lock is held. If it is dropped and re-acquired,
93 * *slept should be set to warn the caller.
95 * Formerly, afs_xvcache was dropped and re-acquired for Solaris, but now it
96 * is not dropped and re-acquired for any platform. It may be that *slept is
97 * therefore obsolescent.
100 osi_VM_FlushVCache(struct vcache *avc, int *slept)
102 if (avc->vrefCount != 0)
108 /* if a lock is held, give up */
109 if (CheckLock(&avc->lock))
113 pvn_vplist_dirty(AFSTOV(avc), 0, NULL, B_TRUNC | B_INVAL, CRED());
116 /* Might as well make the obvious check */
117 if (AFSTOV(avc)->v_pages)
118 return EBUSY; /* should be all gone still */
120 rw_destroy(&avc->rwlock);
130 /* Try to store pages to cache, in order to store a file back to the server.
132 * Locking: the vcache entry's lock is held. It will usually be dropped and
136 osi_VM_StoreAllSegments(struct vcache *avc)
139 (void)pvn_vplist_dirty(AFSTOV(avc), (u_offset_t) 0, afs_putapage, 0,
144 /* Try to invalidate pages, for "fs flush" or "fs flushv"; or
145 * try to free pages, when deleting a file.
147 * Locking: the vcache entry's lock is held. It may be dropped and
151 osi_VM_TryToSmush(struct vcache *avc, afs_ucred_t *acred, int sync)
154 (void)pvn_vplist_dirty(AFSTOV(avc), (u_offset_t) 0, afs_putapage,
155 (sync ? B_INVAL : B_FREE), acred);
159 /* Purge VM for a file when its callback is revoked.
161 * Locking: No lock is held, not even the global lock.
164 osi_VM_FlushPages(struct vcache *avc, afs_ucred_t *credp)
166 extern int afs_pvn_vptrunc;
169 (void)afs_putpage(AFSTOV(avc), (offset_t) 0, 0, B_TRUNC | B_INVAL, credp);
172 /* Zero no-longer-used part of last page, when truncating a file
174 * This function only exists for Solaris. Other platforms do not support it.
176 * Locking: the vcache entry lock is held. It is released and re-obtained.
177 * The caller will raise activeV (to prevent pageins), but this function must
178 * be called first, since it causes a pagein.
181 osi_VM_PreTruncate(struct vcache *avc, int alen, afs_ucred_t *acred)
184 int pageOffset = (alen & PAGEOFFSET);
186 if (pageOffset == 0) {
190 ReleaseWriteLock(&avc->lock);
192 pp = page_lookup(AFSTOV(avc), alen - pageOffset, SE_EXCL);
194 pagezero(pp, pageOffset, PAGESIZE - pageOffset);
198 ObtainWriteLock(&avc->lock, 563);
201 /* Purge pages beyond end-of-file, when truncating a file.
203 * Locking: no lock is held, not even the global lock.
204 * Pageins are blocked (activeV is raised).
207 osi_VM_Truncate(struct vcache *avc, int alen, afs_ucred_t *acred)
210 * It's OK to specify afs_putapage here, even though we aren't holding
211 * the vcache entry lock, because it isn't going to get called.
213 pvn_vplist_dirty(AFSTOV(avc), alen, afs_putapage, B_TRUNC | B_INVAL,