Beispiel #1
0
int
vtfileflush(VtFile *f)
{
	int ret;
	VtBlock *b;
	VtEntry e;

	assert(ISLOCKED(f));
	b = fileload(f, &e);
	if(!(e.flags&VtEntryLocal)){
		vtblockput(b);
		return 0;
	}

	ret = flushblock(f->c, nil, e.score, e.psize/VtScoreSize, e.dsize/VtEntrySize,
		e.type);
	if(ret < 0){
		vtblockput(b);
		return -1;
	}

	vtentrypack(&e, b->data, f->offset % f->epb);
	vtblockput(b);
	return 0;
}
Beispiel #2
0
/*
 * Change the depth of the VtFile r.
 * The entry e for r is contained in block p.
 */
static int
growdepth(VtFile *r, VtBlock *p, VtEntry *e, int depth)
{
	VtBlock *b, *bb;

	assert(ISLOCKED(r));
	assert(depth <= VtPointerDepth);

	b = vtcacheglobal(r->c, e->score, e->type);
	if(b == nil)
		return -1;

	/*
	 * Keep adding layers until we get to the right depth
	 * or an error occurs.
	 */
	while(DEPTH(e->type) < depth){
		bb = vtcacheallocblock(r->c, e->type+1);
		if(bb == nil)
			break;
		memmove(bb->data, b->score, VtScoreSize);
		memmove(e->score, bb->score, VtScoreSize);	
		e->type++;
		e->flags |= VtEntryLocal;
		vtblockput(b);
		b = bb;
	}

	vtentrypack(e, p->data, r->offset % r->epb);
	vtblockput(b);

	if(DEPTH(e->type) == depth)
		return 0;
	return -1;
}
Beispiel #3
0
static int
flushblock(VtCache *c, VtBlock *bb, uint8_t score[VtScoreSize], int ppb,
	   int epb,
	int type)
{
	uint32_t addr;
	VtBlock *b;
	VtEntry e;
	int i;

	addr = vtglobaltolocal(score);
	if(addr == NilBlock)
		return 0;

	if(bb){
		b = bb;
		if(memcmp(b->score, score, VtScoreSize) != 0)
			abort();
	}else
		if((b = vtcachelocal(c, addr, type)) == nil)
			return -1;

	switch(type){
	case VtDataType:
		break;

	case VtDirType:
		for(i=0; i<epb; i++){
			if(vtentryunpack(&e, b->data, i) < 0)
				goto Err;
			if(!(e.flags&VtEntryActive))
				continue;
			if(flushblock(c, nil, e.score, e.psize/VtScoreSize, e.dsize/VtEntrySize,
				e.type) < 0)
				goto Err;
			vtentrypack(&e, b->data, i);
		}
		break;
	
	default:	/* VtPointerTypeX */
		for(i=0; i<ppb; i++){
			if(flushblock(c, nil, b->data+VtScoreSize*i, ppb, epb, type-1) < 0)
				goto Err;
		}
		break;
	}

	if(vtblockwrite(b) < 0)
		goto Err;
	memmove(score, b->score, VtScoreSize);
	if(b != bb)
		vtblockput(b);
	return 0;

Err:
	if(b != bb)
		vtblockput(b);
	return -1;
}
Beispiel #4
0
VtBlock *
vtfileblock(VtFile *r, u32int bn, int mode)
{
	VtBlock *b, *bb;
	int index[VtPointerDepth+1];
	VtEntry e;
	int i;
	int m;

	assert(ISLOCKED(r));
	assert(bn != NilBlock);

	b = fileload(r, &e);
	if(b == nil)
		return nil;

	i = mkindices(&e, bn, index);
	if(i < 0)
		goto Err;
	if(i > DEPTH(e.type)){
		if(mode == VtOREAD){
			werrstr("bad address 0x%lux", (ulong)bn);
			goto Err;
		}
		index[i] = 0;
		if(growdepth(r, b, &e, i) < 0)
			goto Err;
	}

assert(b->type == VtDirType);

	index[DEPTH(e.type)] = r->offset % r->epb;

	/* mode for intermediate block */
	m = mode;
	/* why is this here? *
	if(m == VtOWRITE)
		m = VtORDWR;
	* well we disable it */

	for(i=DEPTH(e.type); i>=0; i--){
		bb = blockwalk(b, index[i], r->c, i==0 ? mode : m, &e);
		if(bb == nil)
			goto Err;
		vtblockput(b);
		b = bb;
	}
	b->pc = getcallerpc(&r);
	return b;
Err:
	vtblockput(b);
	return nil;
}
Beispiel #5
0
int
vtfilesetsize(VtFile *r, u64int size)
{
	int depth, edepth;
	VtEntry e;
	VtBlock *b;

	assert(ISLOCKED(r));
	if(size == 0)
		return vtfiletruncate(r);

	if(size > VtMaxFileSize || size > ((uvlong)MaxBlock)*r->dsize){
		werrstr(ETooBig);
		return -1;
	}

	b = fileload(r, &e);
	if(b == nil)
		return -1;

	/* quick out */
	if(e.size == size){
		vtblockput(b);
		return 0;
	}

	depth = sizetodepth(size, e.psize, e.dsize);
	edepth = DEPTH(e.type);
	if(depth < edepth){
		if(shrinkdepth(r, b, &e, depth) < 0){
			vtblockput(b);
			return -1;
		}
	}else if(depth > edepth){
		if(growdepth(r, b, &e, depth) < 0){
			vtblockput(b);
			return -1;
		}
	}

	if(size < e.size)
		shrinksize(r, &e, size);

	e.size = size;
	vtentrypack(&e, b->data, r->offset % r->epb);
	vtblockput(b);

	return 0;
}
Beispiel #6
0
long
vtfileread(VtFile *f, void *data, long count, vlong offset)
{
	int frag;
	VtBlock *b;
	VtEntry e;

	assert(ISLOCKED(f));

	vtfilegetentry(f, &e);
	if(count == 0)
		return 0;
	if(count < 0 || offset < 0){
		werrstr("vtfileread: bad offset or count");
		return -1;
	}
	if(offset >= e.size)
		return 0;

	if(offset+count > e.size)
		count = e.size - offset;

	frag = offset % e.dsize;
	if(frag+count > e.dsize)
		count = e.dsize - frag;

	b = vtfileblock(f, offset/e.dsize, VtOREAD);
	if(b == nil)
		return -1;

	memmove(data, b->data+frag, count);
	vtblockput(b);
	return count;
}
Beispiel #7
0
/*
 * Lock two (usually sibling) VtFiles.  This needs special care
 * because the Entries for both vtFiles might be in the same block.
 * We also try to lock blocks in left-to-right order within the tree.
 */
int
vtfilelock2(VtFile *r, VtFile *rr, int mode)
{
	VtBlock *b, *bb;

	if(rr == nil)
		return vtfilelock(r, mode);

	if(mode == -1)
		mode = r->mode;

	if(r->parent==rr->parent && r->offset/r->epb == rr->offset/rr->epb){
		b = fileloadblock(r, mode);
		if(b == nil)
			return -1;
		vtblockduplock(b);
		bb = b;
	}else if(r->parent==rr->parent || r->offset > rr->offset){
		bb = fileloadblock(rr, mode);
		b = fileloadblock(r, mode);
	}else{
		b = fileloadblock(r, mode);
		bb = fileloadblock(rr, mode);
	}
	if(b == nil || bb == nil){
		if(b)
			vtblockput(b);
		if(bb)
			vtblockput(bb);
		return -1;
	}

	/*
	 * The fact that we are holding b and bb serves
	 * as the lock entitling us to write to r->b and rr->b.
	 */
	r->b = b;
	rr->b = bb;
	b->pc = getcallerpc(&r);
	bb->pc = getcallerpc(&r);
	return 0;
}
Beispiel #8
0
int
vtfilegetentry(VtFile *r, VtEntry *e)
{
	VtBlock *b;

	assert(ISLOCKED(r));
	b = fileload(r, e);
	if(b == nil)
		return -1;
	vtblockput(b);

	return 0;
}
Beispiel #9
0
VtFile *
vtfileroot(VtCache *c, u32int addr, int mode)
{
	VtFile *r;
	VtBlock *b;

	b = vtcachelocal(c, addr, VtDirType);
	if(b == nil)
		return nil;
	r = vtfilealloc(c, b, nil, 0, mode);
	vtblockput(b);
	return r;
}
Beispiel #10
0
void
vtfileunlock(VtFile *r)
{
	VtBlock *b;

	if(r->b == nil){
		fprint(2, "vtfileunlock: already unlocked\n");
		abort();
	}
	b = r->b;
	r->b = nil;
	vtblockput(b);
}
Beispiel #11
0
static int
vtfilekill(VtFile *r, int doremove)
{
	VtEntry e;
	VtBlock *b;

	assert(ISLOCKED(r));
	b = fileload(r, &e);
	if(b == nil)
		return -1;

	if(doremove==0 && e.size == 0){
		/* already truncated */
		vtblockput(b);
		return 0;
	}

	if(doremove){
		if(e.gen != ~0)
			e.gen++;
		e.dsize = 0;
		e.psize = 0;
		e.flags = 0;
	}else
		e.flags &= ~VtEntryLocal;
	e.type = 0;
	e.size = 0;
	memmove(e.score, vtzeroscore, VtScoreSize);
	vtentrypack(&e, b->data, r->offset % r->epb);
	vtblockput(b);

	if(doremove){
		vtfileunlock(r);
		vtfileclose(r);
	}

	return 0;
}
Beispiel #12
0
uvlong
vtfilegetsize(VtFile *r)
{
	VtEntry e;
	VtBlock *b;

	assert(ISLOCKED(r));
	b = fileload(r, &e);
	if(b == nil)
		return ~(uvlong)0;
	vtblockput(b);

	return e.size;
}
Beispiel #13
0
int
vtfilesetentry(VtFile *r, VtEntry *e)
{
	VtBlock *b;
	VtEntry ee;

	assert(ISLOCKED(r));
	b = fileload(r, &ee);
	if(b == nil)
		return -1;
	vtentrypack(e, b->data, r->offset % r->epb);
	vtblockput(b);
	return 0;
}
Beispiel #14
0
VtFile*
vtfileopenroot(VtCache *c, VtEntry *e)
{
	VtBlock *b;
	VtFile *f;

	b = vtcacheallocblock(c, VtDirType);
	if(b == nil)
		return nil;

	vtentrypack(e, b->data, 0);
	f = vtfilealloc(c, b, nil, 0, VtORDWR);
	vtblockput(b);
	return f;
}
Beispiel #15
0
int
vtfileblockscore(VtFile *r, u32int bn, uchar score[VtScoreSize])
{
	VtBlock *b, *bb;
	int index[VtPointerDepth+1];
	VtEntry e;
	int i;

	assert(ISLOCKED(r));
	assert(bn != NilBlock);

	b = fileload(r, &e);
	if(b == nil)
		return -1;

	if(DEPTH(e.type) == 0){
		memmove(score, e.score, VtScoreSize);
		vtblockput(b);
		return 0;
	}

	i = mkindices(&e, bn, index);
	if(i < 0){
		vtblockput(b);
		return -1;
	}
	if(i > DEPTH(e.type)){
		memmove(score, vtzeroscore, VtScoreSize);
		vtblockput(b);
		return 0;
	}

	index[DEPTH(e.type)] = r->offset % r->epb;

	for(i=DEPTH(e.type); i>=1; i--){
		bb = blockwalk(b, index[i], r->c, VtOREAD, &e);
		if(bb == nil)
			goto Err;
		vtblockput(b);
		b = bb;
		if(memcmp(b->score, vtzeroscore, VtScoreSize) == 0)
			break;
	}

	memmove(score, b->data+index[0]*VtScoreSize, VtScoreSize);
	vtblockput(b);
	return 0;

Err:
	vtblockput(b);
	return -1;
}
Beispiel #16
0
VtFile *
vtfileopen(VtFile *r, u32int offset, int mode)
{
	ulong bn;
	VtBlock *b;

	assert(ISLOCKED(r));
	if(!r->dir){
		werrstr(ENotDir);
		return nil;
	}

	bn = offset/(r->dsize/VtEntrySize);

	b = vtfileblock(r, bn, mode);
	if(b == nil)
		return nil;
	r = vtfilealloc(r->c, b, r, offset, mode);
	vtblockput(b);
	return r;
}
Beispiel #17
0
static long
filewrite1(VtFile *f, void *data, long count, vlong offset)
{
	int frag, m;
	VtBlock *b;
	VtEntry e;

	vtfilegetentry(f, &e);
	if(count < 0 || offset < 0){
		werrstr("vtfilewrite: bad offset or count");
		return -1;
	}

	frag = offset % e.dsize;
	if(frag+count > e.dsize)
		count = e.dsize - frag;

	m = VtORDWR;
	if(frag == 0 && count == e.dsize)
		m = VtOWRITE;

	b = vtfileblock(f, offset/e.dsize, m);
	if(b == nil)
		return -1;

	memmove(b->data+frag, data, count);
	if(m == VtOWRITE && frag+count < e.dsize)
		memset(b->data+frag+count, 0, e.dsize-frag-count);

	if(offset+count > e.size){
		vtfilegetentry(f, &e);
		e.size = offset+count;
		vtfilesetentry(f, &e);
	}

	vtblockput(b);
	return count;
}
Beispiel #18
0
void
threadmain(int argc, char **argv)
{
	char *pref, *mountname, *mountplace;
	uchar score[VtScoreSize], prev[VtScoreSize];
	int i, fd, csize;
	vlong bsize;
	Tm tm;
	VtEntry e;
	VtBlock *b;
	VtCache *c;
	VtRoot root;
	char *tmp, *tmpnam;

	fmtinstall('F', vtfcallfmt);
	fmtinstall('H', encodefmt);
	fmtinstall('T', timefmt);
	fmtinstall('V', vtscorefmt);

	mountname = sysname();
	mountplace = nil;
	ARGBEGIN{
	default:
		usage();
		break;
	case 'D':
		debug++;
		break;
	case 'V':
		chattyventi = 1;
		break;
	case 'f':
		fastwrites = 1;
		break;
	case 'i':
		incremental = 1;
		break;
	case 'm':
		mountname = EARGF(usage());
		break;
	case 'M':
		mountplace = EARGF(usage());
		i = strlen(mountplace);
		if(i > 0 && mountplace[i-1] == '/')
			mountplace[i-1] = 0;
		break;
	case 'n':
		nop = 1;
		break;
	case 's':
		statustime = atoi(EARGF(usage()));
		break;
	case 'v':
		verbose = 1;
		break;
	case 'w':
		nwritethread = atoi(EARGF(usage()));
		break;
	}ARGEND

	if(argc != 1 && argc != 2)
		usage();

	if(statustime)
		print("# %T vbackup %s %s\n", argv[0], argc>=2 ? argv[1] : "");

	/*
	 * open fs
	 */
	if((disk = diskopenfile(argv[0])) == nil)
		sysfatal("diskopen: %r");
	if((disk = diskcache(disk, 32768, 2*MAXQ+16)) == nil)
		sysfatal("diskcache: %r");
	if((fsys = fsysopen(disk)) == nil)
		sysfatal("fsysopen: %r");

	/*
	 * connect to venti
	 */
	if((z = vtdial(nil)) == nil)
		sysfatal("vtdial: %r");
	if(vtconnect(z) < 0)
		sysfatal("vtconnect: %r");

	/*
	 * set up venti block cache
	 */
	zero = vtmallocz(fsys->blocksize);
	bsize = fsys->blocksize;
	csize = 50;	/* plenty; could probably do with 5 */

	if(verbose)
		fprint(2, "cache %d blocks\n", csize);
	c = vtcachealloc(z, bsize*csize);
	zcache = c;

	/*
	 * parse starting score
	 */
	memset(prev, 0, sizeof prev);
	if(argc == 1){
		vfile = vtfilecreateroot(c, (fsys->blocksize/VtScoreSize)*VtScoreSize,
			fsys->blocksize, VtDataType);
		if(vfile == nil)
			sysfatal("vtfilecreateroot: %r");
		vtfilelock(vfile, VtORDWR);
		if(vtfilewrite(vfile, zero, 1, bsize*fsys->nblock-1) != 1)
			sysfatal("vtfilewrite: %r");
		if(vtfileflush(vfile) < 0)
			sysfatal("vtfileflush: %r");
	}else{
		if(vtparsescore(argv[1], &pref, score) < 0)
			sysfatal("bad score: %r");
		if(pref!=nil && strcmp(pref, fsys->type) != 0)
			sysfatal("score is %s but fsys is %s", pref, fsys->type);
		b = vtcacheglobal(c, score, VtRootType, VtRootSize);
		if(b){
			if(vtrootunpack(&root, b->data) < 0)
				sysfatal("bad root: %r");
			if(strcmp(root.type, fsys->type) != 0)
				sysfatal("root is %s but fsys is %s", root.type, fsys->type);
			memmove(prev, score, VtScoreSize);
			memmove(score, root.score, VtScoreSize);
			vtblockput(b);
		}
		b = vtcacheglobal(c, score, VtDirType, VtEntrySize);
		if(b == nil)
			sysfatal("vtcacheglobal %V: %r", score);
		if(vtentryunpack(&e, b->data, 0) < 0)
			sysfatal("%V: vtentryunpack failed", score);
		if(verbose)
			fprint(2, "entry: size %llud psize %d dsize %d\n",
				e.size, e.psize, e.dsize);
		vtblockput(b);
		if((vfile = vtfileopenroot(c, &e)) == nil)
			sysfatal("vtfileopenroot: %r");
		vtfilelock(vfile, VtORDWR);
		if(e.dsize != bsize)
			sysfatal("file system block sizes don't match %d %lld", e.dsize, bsize);
		if(e.size != fsys->nblock*bsize)
			sysfatal("file system block counts don't match %lld %lld", e.size, fsys->nblock*bsize);
	}

	tmpnam = nil;
	if(incremental){
		if(vtfilegetentry(vfile, &e) < 0)
			sysfatal("vtfilegetentry: %r");
		if((vscores = vtfileopenroot(c, &e)) == nil)
			sysfatal("vtfileopenroot: %r");
		vtfileunlock(vfile);
	}else{
		/*
		 * write scores of blocks into temporary file
		 */
		if((tmp = getenv("TMP")) != nil){
			/* okay, good */
		}else if(access("/var/tmp", 0) >= 0)
			tmp = "/var/tmp";
		else
			tmp = "/tmp";
		tmpnam = smprint("%s/vbackup.XXXXXX", tmp);
		if(tmpnam == nil)
			sysfatal("smprint: %r");
	
		if((fd = opentemp(tmpnam, ORDWR|ORCLOSE)) < 0)
			sysfatal("opentemp %s: %r", tmpnam);
		if(statustime)
			print("# %T reading scores into %s\n", tmpnam);
		if(verbose)
			fprint(2, "read scores into %s...\n", tmpnam);
	
		Binit(&bscores, fd, OWRITE);
		for(i=0; i<fsys->nblock; i++){
			if(vtfileblockscore(vfile, i, score) < 0)
				sysfatal("vtfileblockhash %d: %r", i);
			if(Bwrite(&bscores, score, VtScoreSize) != VtScoreSize)
				sysfatal("Bwrite: %r");
		}
		Bterm(&bscores);
		vtfileunlock(vfile);
	
		/*
		 * prep scores for rereading
		 */
		seek(fd, 0, 0);
		Binit(&bscores, fd, OREAD);
	}

	/*
	 * start the main processes 
	 */
	if(statustime)
		print("# %T starting procs\n");
	qcmp = qalloc();
	qventi = qalloc();

	rlock(&endlk);
	proccreate(fsysproc, nil, STACK);
	rlock(&endlk);
	proccreate(ventiproc, nil, STACK);
	rlock(&endlk);
	proccreate(cmpproc, nil, STACK);
	if(statustime){
		rlock(&endlk);
		proccreate(statusproc, nil, STACK);
	}

	/*
	 * wait for processes to finish
	 */
	wlock(&endlk);
	
	qfree(qcmp);
	qfree(qventi);

	if(statustime)
		print("# %T procs exited: %d of %d %d-byte blocks changed, "
			"%d read, %d written, %d skipped, %d copied\n",
			nchange, fsys->nblock, fsys->blocksize,
			vtcachenread, vtcachenwrite, nskip, vtcachencopy);

	/*
	 * prepare root block
	 */
	if(incremental)
		vtfileclose(vscores);
	vtfilelock(vfile, -1);
	if(vtfileflush(vfile) < 0)
		sysfatal("vtfileflush: %r");
	if(vtfilegetentry(vfile, &e) < 0)
		sysfatal("vtfilegetentry: %r");
	vtfileunlock(vfile);
	vtfileclose(vfile);

	b = vtcacheallocblock(c, VtDirType, VtEntrySize);
	if(b == nil)
		sysfatal("vtcacheallocblock: %r");
	vtentrypack(&e, b->data, 0);
	if(vtblockwrite(b) < 0)
		sysfatal("vtblockwrite: %r");

	memset(&root, 0, sizeof root);
	strecpy(root.name, root.name+sizeof root.name, argv[0]);
	strecpy(root.type, root.type+sizeof root.type, fsys->type);
	memmove(root.score, b->score, VtScoreSize);
	root.blocksize = fsys->blocksize;
	memmove(root.prev, prev, VtScoreSize);
	vtblockput(b);

	b = vtcacheallocblock(c, VtRootType, VtRootSize);
	if(b == nil)
		sysfatal("vtcacheallocblock: %r");
	vtrootpack(&root, b->data);
	if(vtblockwrite(b) < 0)
		sysfatal("vtblockwrite: %r");

	tm = *localtime(time(0));
	tm.year += 1900;
	tm.mon++;
	if(mountplace == nil)
		mountplace = guessmountplace(argv[0]);
	print("mount /%s/%d/%02d%02d%s %s:%V %d/%02d%02d/%02d%02d\n",
		mountname, tm.year, tm.mon, tm.mday, 
		mountplace,
		root.type, b->score,
		tm.year, tm.mon, tm.mday, tm.hour, tm.min);
	print("# %T %s %s:%V\n", argv[0], root.type, b->score);
	if(statustime)
		print("# %T venti sync\n");
	vtblockput(b);
	if(vtsync(z) < 0)
		sysfatal("vtsync: %r");
	if(statustime)
		print("# %T synced\n");
	
	fsysclose(fsys);
	diskclose(disk);
	vtcachefree(zcache);

	// Vtgoodbye hangs on Linux - not sure why.
	// Probably vtfcallrpc doesn't quite get the
	// remote hangup right.  Also probably related
	// to the vtrecvproc problem below.
	// vtgoodbye(z);

	// Leak here, because I can't seem to make
	// the vtrecvproc exit.
	// vtfreeconn(z);

	free(tmpnam);
	z = nil;
	zcache = nil;
	fsys = nil;
	disk = nil;
	threadexitsall(nil);
}
Beispiel #19
0
int
vtfileflushbefore(VtFile *r, u64int offset)
{
	VtBlock *b, *bb;
	VtEntry e;
	int i, base, depth, ppb, epb, doflush;
	int index[VtPointerDepth+1], j, ret;
	VtBlock *bi[VtPointerDepth+2];
	uchar *score;

	assert(ISLOCKED(r));
	if(offset == 0)
		return 0;

	b = fileload(r, &e);
	if(b == nil)
		return -1;

	/*
	 * compute path through tree for the last written byte and the next one.
	 */
	ret = -1;
	memset(bi, 0, sizeof bi);
	depth = DEPTH(e.type);
	bi[depth+1] = b;
	i = mkindices(&e, (offset-1)/e.dsize, index);
	if(i < 0)
		goto Err;
	if(i > depth)
		goto Err;
	ppb = e.psize / VtScoreSize;
	epb = e.dsize / VtEntrySize;

	/*
	 * load the blocks along the last written byte
	 */
	index[depth] = r->offset % r->epb;
	for(i=depth; i>=0; i--){
		bb = blockwalk(b, index[i], r->c, VtORDWR, &e);
		if(bb == nil)
			goto Err;
		bi[i] = bb;
		b = bb;
	}
	ret = 0;

	/*
	 * walk up the path from leaf to root, flushing anything that
	 * has been finished.
	 */
	base = e.type&~VtTypeDepthMask;
	for(i=0; i<=depth; i++){
		doflush = 0;
		if(i == 0){
			/* leaf: data or dir block */
			if(offset%e.dsize == 0)
				doflush = 1;
		}else{
			/*
			 * interior node: pointer blocks.
			 * specifically, b = bi[i] is a block whose index[i-1]'th entry 
			 * points at bi[i-1].  
			 */
			b = bi[i];

			/*
			 * the index entries up to but not including index[i-1] point at 
			 * finished blocks, so flush them for sure.
			 */
			for(j=0; j<index[i-1]; j++)
				if(flushblock(r->c, nil, b->data+j*VtScoreSize, ppb, epb, base+i-1) < 0)
					goto Err;

			/*
			 * if index[i-1] is the last entry in the block and is global
			 * (i.e. the kid is flushed), then we can flush this block.
			 */
			if(j==ppb-1 && vtglobaltolocal(b->data+j*VtScoreSize)==NilBlock)
				doflush = 1;
		}
		if(doflush){
			if(i == depth)
				score = e.score;
			else
				score = bi[i+1]->data+index[i]*VtScoreSize;
			if(flushblock(r->c, bi[i], score, ppb, epb, base+i) < 0)
				goto Err;
		}
	}

Err:
	/* top: entry.  do this always so that the score is up-to-date */
	vtentrypack(&e, bi[depth+1]->data, index[depth]);
	for(i=0; i<nelem(bi); i++)
		if(bi[i])
			vtblockput(bi[i]);
	return ret;
}
Beispiel #20
0
static int
shrinkdepth(VtFile *r, VtBlock *p, VtEntry *e, int depth)
{
	VtBlock *b, *nb, *ob, *rb;
	VtEntry oe;

	assert(ISLOCKED(r));
	assert(depth <= VtPointerDepth);

	rb = vtcacheglobal(r->c, e->score, e->type);
	if(rb == nil)
		return -1;

	/*
	 * Walk down to the new root block.
	 * We may stop early, but something is better than nothing.
	 */
	oe = *e;

	ob = nil;
	b = rb;
	for(; DEPTH(e->type) > depth; e->type--){
		nb = vtcacheglobal(r->c, b->data, e->type-1);
		if(nb == nil)
			break;
		if(ob!=nil && ob!=rb)
			vtblockput(ob);
		ob = b;
		b = nb;
	}

	if(b == rb){
		vtblockput(rb);
		return 0;
	}

	/*
	 * Right now, e points at the root block rb, b is the new root block,
	 * and ob points at b.  To update:
	 *
	 *	(i) change e to point at b
	 *	(ii) zero the pointer ob -> b
	 *	(iii) free the root block
	 *
	 * p (the block containing e) must be written before
	 * anything else.
 	 */

	/* (i) */
	memmove(e->score, b->score, VtScoreSize);
	vtentrypack(e, p->data, r->offset % r->epb);

	/* (ii) */
	memmove(ob->data, vtzeroscore, VtScoreSize);

	/* (iii) */
	vtblockput(rb);
	if(ob!=nil && ob!=rb)
		vtblockput(ob);
	vtblockput(b);

	if(DEPTH(e->type) == depth)
		return 0;
	return -1;
}
Beispiel #21
0
VtFile*
_vtfilecreate(VtFile *r, int o, int psize, int dsize, int type)
{
	int i;
	VtBlock *b;
	u32int bn, size;
	VtEntry e;
	int epb;
	VtFile *rr;
	u32int offset;
	
	assert(ISLOCKED(r));
	assert(psize <= VtMaxLumpSize);
	assert(dsize <= VtMaxLumpSize);
	assert(type == VtDirType || type == VtDataType);

	if(!r->dir){
		werrstr(ENotDir);
		return nil;
	}

	epb = r->dsize/VtEntrySize;

	size = vtfilegetdirsize(r);
	/*
	 * look at a random block to see if we can find an empty entry
	 */
	if(o == -1){
		offset = lnrand(size+1);
		offset -= offset % epb;
	}else
		offset = o;

	/* try the given block and then try the last block */
	for(;;){
		bn = offset/epb;
		b = vtfileblock(r, bn, VtORDWR);
		if(b == nil)
			return nil;
		for(i=offset%r->epb; i<epb; i++){
			if(vtentryunpack(&e, b->data, i) < 0)
				continue;
			if((e.flags&VtEntryActive) == 0 && e.gen != ~0)
				goto Found;
		}
		vtblockput(b);
		if(offset == size){
			fprint(2, "vtfilecreate: cannot happen\n");
			werrstr("vtfilecreate: cannot happen");
			return nil;
		}
		offset = size;
	}

Found:
	/* found an entry - gen already set */
	e.psize = psize;
	e.dsize = dsize;
	e.flags = VtEntryActive;
	e.type = type;
	e.size = 0;
	memmove(e.score, vtzeroscore, VtScoreSize);
	vtentrypack(&e, b->data, i);

	offset = bn*epb + i;
	if(offset+1 > size){
		if(vtfilesetdirsize(r, offset+1) < 0){
			vtblockput(b);
			return nil;
		}
	}

	rr = vtfilealloc(r->c, b, r, offset, VtORDWR);
	vtblockput(b);
	return rr;
}
Beispiel #22
0
static int
shrinksize(VtFile *r, VtEntry *e, uvlong size)
{
	int i, depth, type, isdir, ppb;
	uvlong ptrsz;
	uchar score[VtScoreSize];
	VtBlock *b;

	b = vtcacheglobal(r->c, e->score, e->type);
	if(b == nil)
		return -1;

	ptrsz = e->dsize;
	ppb = e->psize/VtScoreSize;
	type = e->type;
	depth = DEPTH(type);
	for(i=0; i+1<depth; i++)
		ptrsz *= ppb;

	isdir = r->dir;
	while(depth > 0){
		if(b->addr == NilBlock){
			/* not worth copying the block just so we can zero some of it */
			vtblockput(b);
			return -1;
		}

		/*
		 * invariant: each pointer in the tree rooted at b accounts for ptrsz bytes
		 */

		/* zero the pointers to unnecessary blocks */
		i = (size+ptrsz-1)/ptrsz;
		for(; i<ppb; i++)
			memmove(b->data+i*VtScoreSize, vtzeroscore, VtScoreSize);

		/* recurse (go around again) on the partially necessary block */
		i = size/ptrsz;
		size = size%ptrsz;
		if(size == 0){
			vtblockput(b);
			return 0;
		}
		ptrsz /= ppb;
		type--;
		memmove(score, b->data+i*VtScoreSize, VtScoreSize);
		vtblockput(b);
		b = vtcacheglobal(r->c, score, type);
		if(b == nil)
			return -1;
	}

	if(b->addr == NilBlock){
		vtblockput(b);
		return -1;
	}

	/*
	 * No one ever truncates BtDir blocks.
	 */
	if(depth==0 && !isdir && e->dsize > size)
		memset(b->data+size, 0, e->dsize-size);
	vtblockput(b);
	return 0;
}