/* Try to discard pages, in order to recycle a vcache entry.
*
* We also make some sanity checks: ref count, open count, held locks.
*
* We also do some non-VM-related chores, such as releasing the cred pointer
* (for AIX and Solaris) and releasing the gnode (for AIX).
*
* Locking: afs_xvcache lock is held. If it is dropped and re-acquired,
* *slept should be set to warn the caller.
*
* Formerly, afs_xvcache was dropped and re-acquired for Solaris, but now it
* is not dropped and re-acquired for any platform. It may be that *slept is
* therefore obsolescent.
*
* OSF/1 Locking: VN_LOCK has been called.
* We do not lock the vnode here, but instead require that it be exclusive
* locked by code calling osi_VM_StoreAllSegments directly, or scheduling it
* from the bqueue - Matt
* Maybe better to just call vnode_pager_setsize()?
*/
int
osi_VM_FlushVCache(struct vcache *avc, int *slept)
{
struct vm_object *obj;
struct vnode *vp;
if (VREFCOUNT(avc) > 1)
return EBUSY;
if (avc->opens)
return EBUSY;
/* if a lock is held, give up */
if (CheckLock(&avc->lock))
return EBUSY;
return(0);
AFS_GUNLOCK();
vp = AFSTOV(avc);
#ifndef AFS_FBSD70_ENV
lock_vnode(vp);
#endif
if (VOP_GETVOBJECT(vp, &obj) == 0) {
VM_OBJECT_LOCK(obj);
vm_object_page_remove(obj, 0, 0, FALSE);
#if 1
if (obj->ref_count == 0) {
simple_lock(&vp->v_interlock);
vgonel(vp, curthread);
vp->v_tag = VT_AFS;
SetAfsVnode(vp);
}
#endif
VM_OBJECT_UNLOCK(obj);
}
#ifndef AFS_FBSD70_ENV
unlock_vnode(vp);
#endif
AFS_GLOCK();
return 0;
}
int
osi_TryEvictVCache(struct vcache *avc, int *slept, int defersleep) {
int code;
struct dentry *dentry;
struct list_head *cur, *head;
/* First, see if we can evict the inode from the dcache */
if (defersleep && avc != afs_globalVp && VREFCOUNT(avc) > 1 && avc->opens == 0) {
*slept = 1;
ReleaseWriteLock(&afs_xvcache);
AFS_GUNLOCK();
afs_linux_lock_dcache();
head = &(AFSTOV(avc))->i_dentry;
restart:
cur = head;
while ((cur = cur->next) != head) {
dentry = list_entry(cur, struct dentry, d_alias);
if (d_unhashed(dentry))
continue;
dget_locked(dentry);
afs_linux_unlock_dcache();
if (d_invalidate(dentry) == -EBUSY) {
dput(dentry);
/* perhaps lock and try to continue? (use cur as head?) */
goto inuse;
}
dput(dentry);
afs_linux_lock_dcache();
goto restart;
}
afs_linux_unlock_dcache();
inuse:
AFS_GLOCK();
ObtainWriteLock(&afs_xvcache, 733);
}
/* Note that we don't set CDirty here, this is OK because the unlink
* RPC is called synchronously */
int
afs_remove(OSI_VC_DECL(adp), char *aname, afs_ucred_t *acred)
{
struct vrequest treq;
register struct dcache *tdc;
struct VenusFid unlinkFid;
register afs_int32 code;
register struct vcache *tvc;
afs_size_t offset, len;
struct afs_fakestat_state fakestate;
OSI_VC_CONVERT(adp);
AFS_STATCNT(afs_remove);
afs_Trace2(afs_iclSetp, CM_TRACE_REMOVE, ICL_TYPE_POINTER, adp,
ICL_TYPE_STRING, aname);
if ((code = afs_InitReq(&treq, acred))) {
return code;
}
afs_InitFakeStat(&fakestate);
AFS_DISCON_LOCK();
code = afs_EvalFakeStat(&adp, &fakestate, &treq);
if (code)
goto done;
/* Check if this is dynroot */
if (afs_IsDynroot(adp)) {
code = afs_DynrootVOPRemove(adp, acred, aname);
goto done;
}
if (afs_IsDynrootMount(adp)) {
code = ENOENT;
goto done;
}
if (strlen(aname) > AFSNAMEMAX) {
code = ENAMETOOLONG;
goto done;
}
tagain:
code = afs_VerifyVCache(adp, &treq);
tvc = NULL;
if (code) {
code = afs_CheckCode(code, &treq, 23);
goto done;
}
/** If the volume is read-only, return error without making an RPC to the
* fileserver
*/
if (adp->f.states & CRO) {
code = EROFS;
goto done;
}
/* If we're running disconnected without logging, go no further... */
if (AFS_IS_DISCONNECTED && !AFS_IS_DISCON_RW) {
code = ENETDOWN;
goto done;
}
tdc = afs_GetDCache(adp, (afs_size_t) 0, &treq, &offset, &len, 1); /* test for error below */
ObtainWriteLock(&adp->lock, 142);
if (tdc)
ObtainSharedLock(&tdc->lock, 638);
/*
* Make sure that the data in the cache is current. We may have
* received a callback while we were waiting for the write lock.
*/
if (!(adp->f.states & CStatd)
|| (tdc && !hsame(adp->f.m.DataVersion, tdc->f.versionNo))) {
ReleaseWriteLock(&adp->lock);
if (tdc) {
ReleaseSharedLock(&tdc->lock);
afs_PutDCache(tdc);
}
goto tagain;
}
unlinkFid.Fid.Vnode = 0;
if (!tvc) {
tvc = osi_dnlc_lookup(adp, aname, WRITE_LOCK);
}
/* This should not be necessary since afs_lookup() has already
* done the work.
*/
if (!tvc)
if (tdc) {
code = afs_dir_Lookup(tdc, aname, &unlinkFid.Fid);
if (code == 0) {
afs_int32 cached = 0;
unlinkFid.Cell = adp->f.fid.Cell;
unlinkFid.Fid.Volume = adp->f.fid.Fid.Volume;
if (unlinkFid.Fid.Unique == 0) {
tvc =
afs_LookupVCache(&unlinkFid, &treq, &cached, adp,
aname);
} else {
ObtainReadLock(&afs_xvcache);
tvc = afs_FindVCache(&unlinkFid, 0, DO_STATS);
ReleaseReadLock(&afs_xvcache);
}
}
}
if (AFS_IS_DISCON_RW) {
if (!adp->f.shadow.vnode && !(adp->f.ddirty_flags & VDisconCreate)) {
/* Make shadow copy of parent dir. */
afs_MakeShadowDir(adp, tdc);
}
/* Can't hold a dcache lock whilst we're getting a vcache one */
if (tdc)
ReleaseSharedLock(&tdc->lock);
/* XXX - We're holding adp->lock still, and we've got no
* guarantee about whether the ordering matches the lock hierarchy */
ObtainWriteLock(&tvc->lock, 713);
/* If we were locally created, then we don't need to do very
* much beyond ensuring that we don't exist anymore */
if (tvc->f.ddirty_flags & VDisconCreate) {
afs_DisconRemoveDirty(tvc);
} else {
/* Add removed file vcache to dirty list. */
afs_DisconAddDirty(tvc, VDisconRemove, 1);
}
adp->f.m.LinkCount--;
ReleaseWriteLock(&tvc->lock);
if (tdc)
ObtainSharedLock(&tdc->lock, 714);
}
if (tvc && osi_Active(tvc)) {
/* about to delete whole file, prefetch it first */
ReleaseWriteLock(&adp->lock);
if (tdc)
ReleaseSharedLock(&tdc->lock);
ObtainWriteLock(&tvc->lock, 143);
FetchWholeEnchilada(tvc, &treq);
ReleaseWriteLock(&tvc->lock);
ObtainWriteLock(&adp->lock, 144);
/* Technically I don't think we need this back, but let's hold it
anyway; The "got" reference should actually be sufficient. */
if (tdc)
ObtainSharedLock(&tdc->lock, 640);
}
osi_dnlc_remove(adp, aname, tvc);
Tadp1 = adp;
#ifndef AFS_DARWIN80_ENV
Tadpr = VREFCOUNT(adp);
#endif
Ttvc = tvc;
Tnam = aname;
Tnam1 = 0;
#ifndef AFS_DARWIN80_ENV
if (tvc)
Ttvcr = VREFCOUNT(tvc);
#endif
#ifdef AFS_AIX_ENV
if (tvc && VREFCOUNT_GT(tvc, 2) && tvc->opens > 0
&& !(tvc->f.states & CUnlinked)) {
#else
if (tvc && VREFCOUNT_GT(tvc, 1) && tvc->opens > 0
&& !(tvc->f.states & CUnlinked)) {
#endif
char *unlname = afs_newname();
ReleaseWriteLock(&adp->lock);
if (tdc)
ReleaseSharedLock(&tdc->lock);
code = afsrename(adp, aname, adp, unlname, acred, &treq);
Tnam1 = unlname;
if (!code) {
struct VenusFid *oldmvid = NULL;
if (tvc->mvid)
oldmvid = tvc->mvid;
tvc->mvid = (struct VenusFid *)unlname;
if (oldmvid)
osi_FreeSmallSpace(oldmvid);
crhold(acred);
if (tvc->uncred) {
crfree(tvc->uncred);
}
tvc->uncred = acred;
tvc->f.states |= CUnlinked;
/* if rename succeeded, remove should not */
ObtainWriteLock(&tvc->lock, 715);
if (tvc->f.ddirty_flags & VDisconRemove) {
tvc->f.ddirty_flags &= ~VDisconRemove;
}
ReleaseWriteLock(&tvc->lock);
} else {
osi_FreeSmallSpace(unlname);
}
if (tdc)
afs_PutDCache(tdc);
afs_PutVCache(tvc);
} else {
code = afsremove(adp, tdc, tvc, aname, acred, &treq);
}
done:
afs_PutFakeStat(&fakestate);
#ifndef AFS_DARWIN80_ENV
/* we can't track by thread, it's not exported in the KPI; only do
this on !macos */
osi_Assert(!WriteLocked(&adp->lock) || (adp->lock.pid_writer != MyPidxx));
#endif
AFS_DISCON_UNLOCK();
return code;
}
/* afs_remunlink -- This tries to delete the file at the server after it has
* been renamed when unlinked locally but now has been finally released.
*
* CAUTION -- may be called with avc unheld. */
int
afs_remunlink(register struct vcache *avc, register int doit)
{
afs_ucred_t *cred;
char *unlname;
struct vcache *adp;
struct vrequest treq;
struct VenusFid dirFid;
register struct dcache *tdc;
afs_int32 code = 0;
if (NBObtainWriteLock(&avc->lock, 423))
return 0;
#if defined(AFS_DARWIN80_ENV)
if (vnode_get(AFSTOV(avc))) {
ReleaseWriteLock(&avc->lock);
return 0;
}
#endif
if (avc->mvid && (doit || (avc->f.states & CUnlinkedDel))) {
if ((code = afs_InitReq(&treq, avc->uncred))) {
ReleaseWriteLock(&avc->lock);
} else {
/* Must bump the refCount because GetVCache may block.
* Also clear mvid so no other thread comes here if we block.
*/
unlname = (char *)avc->mvid;
avc->mvid = NULL;
cred = avc->uncred;
avc->uncred = NULL;
#if defined(AFS_DARWIN_ENV) && !defined(AFS_DARWIN80_ENV)
VREF(AFSTOV(avc));
#else
AFS_FAST_HOLD(avc);
#endif
/* We'll only try this once. If it fails, just release the vnode.
* Clear after doing hold so that NewVCache doesn't find us yet.
*/
avc->f.states &= ~(CUnlinked | CUnlinkedDel);
ReleaseWriteLock(&avc->lock);
dirFid.Cell = avc->f.fid.Cell;
dirFid.Fid.Volume = avc->f.fid.Fid.Volume;
dirFid.Fid.Vnode = avc->f.parent.vnode;
dirFid.Fid.Unique = avc->f.parent.unique;
adp = afs_GetVCache(&dirFid, &treq, NULL, NULL);
if (adp) {
tdc = afs_FindDCache(adp, (afs_size_t) 0);
ObtainWriteLock(&adp->lock, 159);
if (tdc)
ObtainSharedLock(&tdc->lock, 639);
/* afsremove releases the adp & tdc locks, and does vn_rele(avc) */
code = afsremove(adp, tdc, avc, unlname, cred, &treq);
afs_PutVCache(adp);
} else {
/* we failed - and won't be back to try again. */
afs_PutVCache(avc);
}
osi_FreeSmallSpace(unlname);
crfree(cred);
}
} else {
#if defined(AFS_DARWIN80_ENV)
vnode_put(AFSTOV(avc));
#endif
ReleaseWriteLock(&avc->lock);
}
return code;
}
int
osi_TryEvictVCache(struct vcache *avc, int *slept, int defersleep) {
int code;
struct dentry *dentry;
struct inode *inode = AFSTOV(avc);
struct list_head *cur, *head;
/* First, see if we can evict the inode from the dcache */
if (defersleep && avc != afs_globalVp && VREFCOUNT(avc) > 1 && avc->opens == 0) {
*slept = 1;
ReleaseWriteLock(&afs_xvcache);
AFS_GUNLOCK();
#if defined(HAVE_DCACHE_LOCK)
spin_lock(&dcache_lock);
head = &inode->i_dentry;
restart:
cur = head;
while ((cur = cur->next) != head) {
dentry = list_entry(cur, struct dentry, d_alias);
if (d_unhashed(dentry))
continue;
dget_locked(dentry);
spin_unlock(&dcache_lock);
if (d_invalidate(dentry) == -EBUSY) {
dput(dentry);
/* perhaps lock and try to continue? (use cur as head?) */
goto inuse;
}
dput(dentry);
spin_lock(&dcache_lock);
goto restart;
}
spin_unlock(&dcache_lock);
#else /* HAVE_DCACHE_LOCK */
spin_lock(&inode->i_lock);
head = &inode->i_dentry;
restart:
cur = head;
while ((cur = cur->next) != head) {
dentry = list_entry(cur, struct dentry, d_alias);
spin_lock(&dentry->d_lock);
if (d_unhashed(dentry)) {
spin_unlock(&dentry->d_lock);
continue;
}
spin_unlock(&dentry->d_lock);
dget(dentry);
spin_unlock(&inode->i_lock);
if (d_invalidate(dentry) == -EBUSY) {
dput(dentry);
/* perhaps lock and try to continue? (use cur as head?) */
goto inuse;
}
dput(dentry);
spin_lock(&inode->i_lock);
goto restart;
}
spin_unlock(&inode->i_lock);
#endif /* HAVE_DCACHE_LOCK */
inuse:
AFS_GLOCK();
ObtainWriteLock(&afs_xvcache, 733);
}
int
SRXAFSCB_GetCE(struct rx_call *a_call, afs_int32 a_index,
struct AFSDBCacheEntry *a_result)
{
int i; /*Loop variable */
struct vcache *tvc; /*Ptr to current cache entry */
int code; /*Return code */
XSTATS_DECLS;
RX_AFS_GLOCK();
XSTATS_START_CMTIME(AFS_STATS_CM_RPCIDX_GETCE);
AFS_STATCNT(SRXAFSCB_GetCE);
for (i = 0; i < VCSIZE; i++) {
for (tvc = afs_vhashT[i]; tvc; tvc = tvc->hnext) {
if (a_index == 0)
goto searchDone;
a_index--;
} /*Zip through current hash chain */
} /*Zip through hash chains */
searchDone:
if (tvc == NULL) {
/*Past EOF */
code = 1;
goto fcnDone;
}
/*
* Copy out the located entry.
*/
a_result->addr = afs_data_pointer_to_int32(tvc);
a_result->cell = tvc->f.fid.Cell;
a_result->netFid.Volume = tvc->f.fid.Fid.Volume;
a_result->netFid.Vnode = tvc->f.fid.Fid.Vnode;
a_result->netFid.Unique = tvc->f.fid.Fid.Unique;
a_result->lock.waitStates = tvc->lock.wait_states;
a_result->lock.exclLocked = tvc->lock.excl_locked;
a_result->lock.readersReading = tvc->lock.readers_reading;
a_result->lock.numWaiting = tvc->lock.num_waiting;
#if defined(INSTRUMENT_LOCKS)
a_result->lock.pid_last_reader = MyPidxx2Pid(tvc->lock.pid_last_reader);
a_result->lock.pid_writer = MyPidxx2Pid(tvc->lock.pid_writer);
a_result->lock.src_indicator = tvc->lock.src_indicator;
#else
/* On osf20 , the vcache does not maintain these three fields */
a_result->lock.pid_last_reader = 0;
a_result->lock.pid_writer = 0;
a_result->lock.src_indicator = 0;
#endif /* INSTRUMENT_LOCKS */
#ifdef AFS_64BIT_CLIENT
a_result->Length = (afs_int32) tvc->f.m.Length & 0xffffffff;
#else /* AFS_64BIT_CLIENT */
a_result->Length = tvc->f.m.Length;
#endif /* AFS_64BIT_CLIENT */
a_result->DataVersion = hgetlo(tvc->f.m.DataVersion);
a_result->callback = afs_data_pointer_to_int32(tvc->callback); /* XXXX Now a pointer; change it XXXX */
a_result->cbExpires = tvc->cbExpires;
if (tvc->f.states & CVInit) {
a_result->refCount = 1;
} else {
#ifdef AFS_DARWIN80_ENV
a_result->refCount = vnode_isinuse(AFSTOV(tvc),0)?1:0; /* XXX fix */
#else
a_result->refCount = VREFCOUNT(tvc);
#endif
}
a_result->opens = tvc->opens;
a_result->writers = tvc->execsOrWriters;
a_result->mvstat = tvc->mvstat;
a_result->states = tvc->f.states;
code = 0;
/*
* Return our results.
*/
fcnDone:
XSTATS_END_TIME;
RX_AFS_GUNLOCK();
return (code);
} /*SRXAFSCB_GetCE */
