2 056fe1ba 2003-11-23 devnull * Manage tree of VtFiles stored in the block cache.
4 056fe1ba 2003-11-23 devnull * The single point of truth for the info about the VtFiles themselves
5 056fe1ba 2003-11-23 devnull * is the block data. Because of this, there is no explicit locking of
6 056fe1ba 2003-11-23 devnull * VtFile structures, and indeed there may be more than one VtFile
7 056fe1ba 2003-11-23 devnull * structure for a given Venti file. They synchronize through the
8 056fe1ba 2003-11-23 devnull * block cache.
10 056fe1ba 2003-11-23 devnull * This is a bit simpler than fossil because there are no epochs
11 056fe1ba 2003-11-23 devnull * or tags or anything else. Just mutable local blocks and immutable
12 056fe1ba 2003-11-23 devnull * Venti blocks.
15 056fe1ba 2003-11-23 devnull #include <u.h>
16 056fe1ba 2003-11-23 devnull #include <libc.h>
17 056fe1ba 2003-11-23 devnull #include <venti.h>
21 056fe1ba 2003-11-23 devnull MaxBlock = (1UL<<31),
24 056fe1ba 2003-11-23 devnull static char EBadEntry[] = "bad VtEntry";
25 056fe1ba 2003-11-23 devnull static char ENotDir[] = "walk in non-directory";
26 056fe1ba 2003-11-23 devnull static char ETooBig[] = "file too big";
27 056fe1ba 2003-11-23 devnull static char EBadAddr[] = "bad address";
28 056fe1ba 2003-11-23 devnull static char ELabelMismatch[] = "label mismatch";
30 056fe1ba 2003-11-23 devnull static int sizetodepth(uvlong s, int psize, int dsize);
31 056fe1ba 2003-11-23 devnull static VtBlock *fileload(VtFile *r, VtEntry *e);
32 056fe1ba 2003-11-23 devnull static int shrinkdepth(VtFile*, VtBlock*, VtEntry*, int);
33 056fe1ba 2003-11-23 devnull static int shrinksize(VtFile*, VtEntry*, uvlong);
34 056fe1ba 2003-11-23 devnull static int growdepth(VtFile*, VtBlock*, VtEntry*, int);
36 056fe1ba 2003-11-23 devnull #define ISLOCKED(r) ((r)->b != nil)
37 056fe1ba 2003-11-23 devnull #define DEPTH(t) ((t)&VtTypeDepthMask)
39 056fe1ba 2003-11-23 devnull static VtFile *
40 056fe1ba 2003-11-23 devnull vtfilealloc(VtCache *c, VtBlock *b, VtFile *p, u32int offset, int mode)
43 056fe1ba 2003-11-23 devnull u32int size;
44 056fe1ba 2003-11-23 devnull VtEntry e;
45 056fe1ba 2003-11-23 devnull VtFile *r;
47 056fe1ba 2003-11-23 devnull assert(p==nil || ISLOCKED(p));
49 056fe1ba 2003-11-23 devnull if(p == nil){
50 056fe1ba 2003-11-23 devnull assert(offset == 0);
53 056fe1ba 2003-11-23 devnull epb = p->dsize / VtEntrySize;
55 056fe1ba 2003-11-23 devnull if(b->type != VtDirType)
56 056fe1ba 2003-11-23 devnull goto Bad;
59 056fe1ba 2003-11-23 devnull * a non-active entry is the only thing that
60 056fe1ba 2003-11-23 devnull * can legitimately happen here. all the others
61 056fe1ba 2003-11-23 devnull * get prints.
63 056fe1ba 2003-11-23 devnull if(vtentryunpack(&e, b->data, offset % epb) < 0){
64 056fe1ba 2003-11-23 devnull fprint(2, "vtentryunpack failed\n");
65 056fe1ba 2003-11-23 devnull goto Bad;
67 056fe1ba 2003-11-23 devnull if(!(e.flags & VtEntryActive)){
68 056fe1ba 2003-11-23 devnull if(0)fprint(2, "not active\n");
69 056fe1ba 2003-11-23 devnull goto Bad;
71 056fe1ba 2003-11-23 devnull if(e.psize < 256 || e.dsize < 256){
72 056fe1ba 2003-11-23 devnull fprint(2, "psize %ud dsize %ud\n", e.psize, e.dsize);
73 056fe1ba 2003-11-23 devnull goto Bad;
76 056fe1ba 2003-11-23 devnull if(DEPTH(e.type) < sizetodepth(e.size, e.psize, e.dsize)){
77 056fe1ba 2003-11-23 devnull fprint(2, "depth %ud size %llud psize %ud dsize %ud\n",
78 056fe1ba 2003-11-23 devnull DEPTH(e.type), e.size, e.psize, e.dsize);
79 056fe1ba 2003-11-23 devnull goto Bad;
82 056fe1ba 2003-11-23 devnull size = vtcacheblocksize(c);
83 056fe1ba 2003-11-23 devnull if(e.dsize > size || e.psize > size){
84 056fe1ba 2003-11-23 devnull fprint(2, "psize %ud dsize %ud blocksize %ud\n", e.psize, e.dsize, size);
85 056fe1ba 2003-11-23 devnull goto Bad;
88 056fe1ba 2003-11-23 devnull r = vtmallocz(sizeof(VtFile));
89 056fe1ba 2003-11-23 devnull r->c = c;
90 056fe1ba 2003-11-23 devnull r->mode = mode;
91 056fe1ba 2003-11-23 devnull r->dsize = e.dsize;
92 056fe1ba 2003-11-23 devnull r->gen = e.gen;
93 d23a617a 2004-03-15 devnull r->dir = (e.type & VtTypeBaseMask) == VtDirType;
94 056fe1ba 2003-11-23 devnull r->ref = 1;
95 056fe1ba 2003-11-23 devnull r->parent = p;
97 056fe1ba 2003-11-23 devnull qlock(&p->lk);
98 056fe1ba 2003-11-23 devnull assert(mode == VtOREAD || p->mode == VtORDWR);
99 056fe1ba 2003-11-23 devnull p->ref++;
100 056fe1ba 2003-11-23 devnull qunlock(&p->lk);
102 056fe1ba 2003-11-23 devnull memmove(r->score, b->score, VtScoreSize);
103 056fe1ba 2003-11-23 devnull r->offset = offset;
104 056fe1ba 2003-11-23 devnull r->epb = epb;
106 056fe1ba 2003-11-23 devnull return r;
108 056fe1ba 2003-11-23 devnull werrstr(EBadEntry);
109 056fe1ba 2003-11-23 devnull return nil;
113 056fe1ba 2003-11-23 devnull VtFile *
114 056fe1ba 2003-11-23 devnull vtfileroot(VtCache *c, u32int addr, int mode)
116 056fe1ba 2003-11-23 devnull VtFile *r;
117 056fe1ba 2003-11-23 devnull VtBlock *b;
119 056fe1ba 2003-11-23 devnull b = vtcachelocal(c, addr, VtDirType);
120 056fe1ba 2003-11-23 devnull if(b == nil)
121 056fe1ba 2003-11-23 devnull return nil;
123 056fe1ba 2003-11-23 devnull r = vtfilealloc(c, b, nil, 0, mode);
124 056fe1ba 2003-11-23 devnull vtblockput(b);
125 056fe1ba 2003-11-23 devnull return r;
129 056fe1ba 2003-11-23 devnull vtfileopenroot(VtCache *c, VtEntry *e)
131 056fe1ba 2003-11-23 devnull VtBlock *b;
132 056fe1ba 2003-11-23 devnull VtFile *f;
134 056fe1ba 2003-11-23 devnull b = vtcacheallocblock(c, VtDirType);
135 056fe1ba 2003-11-23 devnull if(b == nil)
136 056fe1ba 2003-11-23 devnull return nil;
138 056fe1ba 2003-11-23 devnull vtentrypack(e, b->data, 0);
139 056fe1ba 2003-11-23 devnull f = vtfilealloc(c, b, nil, 0, VtORDWR);
140 056fe1ba 2003-11-23 devnull vtblockput(b);
141 056fe1ba 2003-11-23 devnull return f;
144 056fe1ba 2003-11-23 devnull VtFile *
145 056fe1ba 2003-11-23 devnull vtfilecreateroot(VtCache *c, int psize, int dsize, int type)
147 056fe1ba 2003-11-23 devnull VtEntry e;
149 056fe1ba 2003-11-23 devnull memset(&e, 0, sizeof e);
150 056fe1ba 2003-11-23 devnull e.flags = VtEntryActive;
151 056fe1ba 2003-11-23 devnull e.psize = psize;
152 056fe1ba 2003-11-23 devnull e.dsize = dsize;
153 d23a617a 2004-03-15 devnull e.type = type;
154 056fe1ba 2003-11-23 devnull memmove(e.score, vtzeroscore, VtScoreSize);
156 056fe1ba 2003-11-23 devnull return vtfileopenroot(c, &e);
159 056fe1ba 2003-11-23 devnull VtFile *
160 056fe1ba 2003-11-23 devnull vtfileopen(VtFile *r, u32int offset, int mode)
162 056fe1ba 2003-11-23 devnull ulong bn;
163 056fe1ba 2003-11-23 devnull VtBlock *b;
165 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
166 056fe1ba 2003-11-23 devnull if(!r->dir){
167 056fe1ba 2003-11-23 devnull werrstr(ENotDir);
168 056fe1ba 2003-11-23 devnull return nil;
171 056fe1ba 2003-11-23 devnull bn = offset/(r->dsize/VtEntrySize);
173 056fe1ba 2003-11-23 devnull b = vtfileblock(r, bn, mode);
174 056fe1ba 2003-11-23 devnull if(b == nil)
175 056fe1ba 2003-11-23 devnull return nil;
176 056fe1ba 2003-11-23 devnull r = vtfilealloc(r->c, b, r, offset, mode);
177 056fe1ba 2003-11-23 devnull vtblockput(b);
178 056fe1ba 2003-11-23 devnull return r;
181 056fe1ba 2003-11-23 devnull VtFile *
182 056fe1ba 2003-11-23 devnull vtfilecreate(VtFile *r, int psize, int dsize, int dir)
185 056fe1ba 2003-11-23 devnull VtBlock *b;
186 056fe1ba 2003-11-23 devnull u32int bn, size;
187 056fe1ba 2003-11-23 devnull VtEntry e;
188 056fe1ba 2003-11-23 devnull int epb;
189 056fe1ba 2003-11-23 devnull VtFile *rr;
190 056fe1ba 2003-11-23 devnull u32int offset;
192 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
194 056fe1ba 2003-11-23 devnull if(!r->dir){
195 056fe1ba 2003-11-23 devnull werrstr(ENotDir);
196 056fe1ba 2003-11-23 devnull return nil;
199 056fe1ba 2003-11-23 devnull epb = r->dsize/VtEntrySize;
201 056fe1ba 2003-11-23 devnull size = vtfilegetdirsize(r);
203 056fe1ba 2003-11-23 devnull * look at a random block to see if we can find an empty entry
205 056fe1ba 2003-11-23 devnull offset = lnrand(size+1);
206 056fe1ba 2003-11-23 devnull offset -= offset % epb;
208 056fe1ba 2003-11-23 devnull /* try the given block and then try the last block */
209 056fe1ba 2003-11-23 devnull for(;;){
210 056fe1ba 2003-11-23 devnull bn = offset/epb;
211 056fe1ba 2003-11-23 devnull b = vtfileblock(r, bn, VtORDWR);
212 056fe1ba 2003-11-23 devnull if(b == nil)
213 056fe1ba 2003-11-23 devnull return nil;
214 056fe1ba 2003-11-23 devnull for(i=offset%r->epb; i<epb; i++){
215 056fe1ba 2003-11-23 devnull if(vtentryunpack(&e, b->data, i) < 0)
216 056fe1ba 2003-11-23 devnull continue;
217 056fe1ba 2003-11-23 devnull if((e.flags&VtEntryActive) == 0 && e.gen != ~0)
218 056fe1ba 2003-11-23 devnull goto Found;
220 056fe1ba 2003-11-23 devnull vtblockput(b);
221 056fe1ba 2003-11-23 devnull if(offset == size){
222 056fe1ba 2003-11-23 devnull fprint(2, "vtfilecreate: cannot happen\n");
223 056fe1ba 2003-11-23 devnull werrstr("vtfilecreate: cannot happen");
224 056fe1ba 2003-11-23 devnull return nil;
226 056fe1ba 2003-11-23 devnull offset = size;
230 056fe1ba 2003-11-23 devnull /* found an entry - gen already set */
231 056fe1ba 2003-11-23 devnull e.psize = psize;
232 056fe1ba 2003-11-23 devnull e.dsize = dsize;
233 056fe1ba 2003-11-23 devnull e.flags = VtEntryActive;
234 056fe1ba 2003-11-23 devnull e.type = dir ? VtDirType : VtDataType;
235 056fe1ba 2003-11-23 devnull e.size = 0;
236 056fe1ba 2003-11-23 devnull memmove(e.score, vtzeroscore, VtScoreSize);
237 056fe1ba 2003-11-23 devnull vtentrypack(&e, b->data, i);
239 056fe1ba 2003-11-23 devnull offset = bn*epb + i;
240 056fe1ba 2003-11-23 devnull if(offset+1 > size){
241 056fe1ba 2003-11-23 devnull if(vtfilesetdirsize(r, offset+1) < 0){
242 056fe1ba 2003-11-23 devnull vtblockput(b);
243 056fe1ba 2003-11-23 devnull return nil;
247 056fe1ba 2003-11-23 devnull rr = vtfilealloc(r->c, b, r, offset, VtORDWR);
248 056fe1ba 2003-11-23 devnull vtblockput(b);
249 056fe1ba 2003-11-23 devnull return rr;
252 056fe1ba 2003-11-23 devnull static int
253 056fe1ba 2003-11-23 devnull vtfilekill(VtFile *r, int doremove)
255 056fe1ba 2003-11-23 devnull VtEntry e;
256 056fe1ba 2003-11-23 devnull VtBlock *b;
258 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
259 056fe1ba 2003-11-23 devnull b = fileload(r, &e);
260 056fe1ba 2003-11-23 devnull if(b == nil)
261 056fe1ba 2003-11-23 devnull return -1;
263 056fe1ba 2003-11-23 devnull if(doremove==0 && e.size == 0){
264 056fe1ba 2003-11-23 devnull /* already truncated */
265 056fe1ba 2003-11-23 devnull vtblockput(b);
266 056fe1ba 2003-11-23 devnull return 0;
269 056fe1ba 2003-11-23 devnull if(doremove){
270 056fe1ba 2003-11-23 devnull if(e.gen != ~0)
271 056fe1ba 2003-11-23 devnull e.gen++;
272 056fe1ba 2003-11-23 devnull e.dsize = 0;
273 056fe1ba 2003-11-23 devnull e.psize = 0;
274 056fe1ba 2003-11-23 devnull e.flags = 0;
276 056fe1ba 2003-11-23 devnull e.flags &= ~VtEntryLocal;
277 056fe1ba 2003-11-23 devnull e.type = 0;
278 056fe1ba 2003-11-23 devnull e.size = 0;
279 056fe1ba 2003-11-23 devnull memmove(e.score, vtzeroscore, VtScoreSize);
280 056fe1ba 2003-11-23 devnull vtentrypack(&e, b->data, r->offset % r->epb);
281 056fe1ba 2003-11-23 devnull vtblockput(b);
283 056fe1ba 2003-11-23 devnull if(doremove){
284 056fe1ba 2003-11-23 devnull vtfileunlock(r);
285 056fe1ba 2003-11-23 devnull vtfileclose(r);
288 056fe1ba 2003-11-23 devnull return 0;
292 056fe1ba 2003-11-23 devnull vtfileremove(VtFile *r)
294 056fe1ba 2003-11-23 devnull return vtfilekill(r, 1);
298 056fe1ba 2003-11-23 devnull vtfiletruncate(VtFile *r)
300 056fe1ba 2003-11-23 devnull return vtfilekill(r, 0);
304 056fe1ba 2003-11-23 devnull vtfilegetsize(VtFile *r)
306 056fe1ba 2003-11-23 devnull VtEntry e;
307 056fe1ba 2003-11-23 devnull VtBlock *b;
309 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
310 056fe1ba 2003-11-23 devnull b = fileload(r, &e);
311 056fe1ba 2003-11-23 devnull if(b == nil)
312 056fe1ba 2003-11-23 devnull return ~(uvlong)0;
313 056fe1ba 2003-11-23 devnull vtblockput(b);
315 056fe1ba 2003-11-23 devnull return e.size;
318 056fe1ba 2003-11-23 devnull static int
319 056fe1ba 2003-11-23 devnull shrinksize(VtFile *r, VtEntry *e, uvlong size)
321 056fe1ba 2003-11-23 devnull int i, depth, type, isdir, ppb;
322 056fe1ba 2003-11-23 devnull uvlong ptrsz;
323 056fe1ba 2003-11-23 devnull uchar score[VtScoreSize];
324 056fe1ba 2003-11-23 devnull VtBlock *b;
326 056fe1ba 2003-11-23 devnull b = vtcacheglobal(r->c, e->score, e->type);
327 056fe1ba 2003-11-23 devnull if(b == nil)
328 056fe1ba 2003-11-23 devnull return -1;
330 056fe1ba 2003-11-23 devnull ptrsz = e->dsize;
331 056fe1ba 2003-11-23 devnull ppb = e->psize/VtScoreSize;
332 056fe1ba 2003-11-23 devnull type = e->type;
333 056fe1ba 2003-11-23 devnull depth = DEPTH(type);
334 056fe1ba 2003-11-23 devnull for(i=0; i+1<depth; i++)
335 056fe1ba 2003-11-23 devnull ptrsz *= ppb;
337 056fe1ba 2003-11-23 devnull isdir = r->dir;
338 056fe1ba 2003-11-23 devnull while(depth > 0){
339 056fe1ba 2003-11-23 devnull if(b->addr == NilBlock){
340 056fe1ba 2003-11-23 devnull /* not worth copying the block just so we can zero some of it */
341 056fe1ba 2003-11-23 devnull vtblockput(b);
342 056fe1ba 2003-11-23 devnull return -1;
346 056fe1ba 2003-11-23 devnull * invariant: each pointer in the tree rooted at b accounts for ptrsz bytes
349 056fe1ba 2003-11-23 devnull /* zero the pointers to unnecessary blocks */
350 056fe1ba 2003-11-23 devnull i = (size+ptrsz-1)/ptrsz;
351 056fe1ba 2003-11-23 devnull for(; i<ppb; i++)
352 056fe1ba 2003-11-23 devnull memmove(b->data+i*VtScoreSize, vtzeroscore, VtScoreSize);
354 056fe1ba 2003-11-23 devnull /* recurse (go around again) on the partially necessary block */
355 056fe1ba 2003-11-23 devnull i = size/ptrsz;
356 056fe1ba 2003-11-23 devnull size = size%ptrsz;
357 056fe1ba 2003-11-23 devnull if(size == 0){
358 056fe1ba 2003-11-23 devnull vtblockput(b);
359 056fe1ba 2003-11-23 devnull return 0;
361 056fe1ba 2003-11-23 devnull ptrsz /= ppb;
363 056fe1ba 2003-11-23 devnull memmove(score, b->data+i*VtScoreSize, VtScoreSize);
364 056fe1ba 2003-11-23 devnull vtblockput(b);
365 056fe1ba 2003-11-23 devnull b = vtcacheglobal(r->c, score, type);
366 056fe1ba 2003-11-23 devnull if(b == nil)
367 056fe1ba 2003-11-23 devnull return -1;
370 056fe1ba 2003-11-23 devnull if(b->addr == NilBlock){
371 056fe1ba 2003-11-23 devnull vtblockput(b);
372 056fe1ba 2003-11-23 devnull return -1;
376 056fe1ba 2003-11-23 devnull * No one ever truncates BtDir blocks.
378 056fe1ba 2003-11-23 devnull if(depth==0 && !isdir && e->dsize > size)
379 056fe1ba 2003-11-23 devnull memset(b->data+size, 0, e->dsize-size);
380 056fe1ba 2003-11-23 devnull vtblockput(b);
381 056fe1ba 2003-11-23 devnull return 0;
385 056fe1ba 2003-11-23 devnull vtfilesetsize(VtFile *r, uvlong size)
387 056fe1ba 2003-11-23 devnull int depth, edepth;
388 056fe1ba 2003-11-23 devnull VtEntry e;
389 056fe1ba 2003-11-23 devnull VtBlock *b;
391 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
392 056fe1ba 2003-11-23 devnull if(size == 0)
393 056fe1ba 2003-11-23 devnull return vtfiletruncate(r);
395 056fe1ba 2003-11-23 devnull if(size > VtMaxFileSize || size > ((uvlong)MaxBlock)*r->dsize){
396 056fe1ba 2003-11-23 devnull werrstr(ETooBig);
397 056fe1ba 2003-11-23 devnull return -1;
400 056fe1ba 2003-11-23 devnull b = fileload(r, &e);
401 056fe1ba 2003-11-23 devnull if(b == nil)
402 056fe1ba 2003-11-23 devnull return -1;
404 056fe1ba 2003-11-23 devnull /* quick out */
405 056fe1ba 2003-11-23 devnull if(e.size == size){
406 056fe1ba 2003-11-23 devnull vtblockput(b);
407 056fe1ba 2003-11-23 devnull return 0;
410 056fe1ba 2003-11-23 devnull depth = sizetodepth(size, e.psize, e.dsize);
411 056fe1ba 2003-11-23 devnull edepth = DEPTH(e.type);
412 056fe1ba 2003-11-23 devnull if(depth < edepth){
413 056fe1ba 2003-11-23 devnull if(shrinkdepth(r, b, &e, depth) < 0){
414 056fe1ba 2003-11-23 devnull vtblockput(b);
415 056fe1ba 2003-11-23 devnull return -1;
417 056fe1ba 2003-11-23 devnull }else if(depth > edepth){
418 056fe1ba 2003-11-23 devnull if(growdepth(r, b, &e, depth) < 0){
419 056fe1ba 2003-11-23 devnull vtblockput(b);
420 056fe1ba 2003-11-23 devnull return -1;
424 056fe1ba 2003-11-23 devnull if(size < e.size)
425 056fe1ba 2003-11-23 devnull shrinksize(r, &e, size);
427 056fe1ba 2003-11-23 devnull e.size = size;
428 056fe1ba 2003-11-23 devnull vtentrypack(&e, b->data, r->offset % r->epb);
429 056fe1ba 2003-11-23 devnull vtblockput(b);
431 056fe1ba 2003-11-23 devnull return 0;
435 056fe1ba 2003-11-23 devnull vtfilesetdirsize(VtFile *r, u32int ds)
437 056fe1ba 2003-11-23 devnull uvlong size;
438 056fe1ba 2003-11-23 devnull int epb;
440 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
441 056fe1ba 2003-11-23 devnull epb = r->dsize/VtEntrySize;
443 056fe1ba 2003-11-23 devnull size = (uvlong)r->dsize*(ds/epb);
444 056fe1ba 2003-11-23 devnull size += VtEntrySize*(ds%epb);
445 056fe1ba 2003-11-23 devnull return vtfilesetsize(r, size);
449 056fe1ba 2003-11-23 devnull vtfilegetdirsize(VtFile *r)
451 056fe1ba 2003-11-23 devnull ulong ds;
452 056fe1ba 2003-11-23 devnull uvlong size;
453 056fe1ba 2003-11-23 devnull int epb;
455 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
456 056fe1ba 2003-11-23 devnull epb = r->dsize/VtEntrySize;
458 056fe1ba 2003-11-23 devnull size = vtfilegetsize(r);
459 056fe1ba 2003-11-23 devnull ds = epb*(size/r->dsize);
460 056fe1ba 2003-11-23 devnull ds += (size%r->dsize)/VtEntrySize;
461 056fe1ba 2003-11-23 devnull return ds;
465 056fe1ba 2003-11-23 devnull vtfilegetentry(VtFile *r, VtEntry *e)
467 056fe1ba 2003-11-23 devnull VtBlock *b;
469 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
470 056fe1ba 2003-11-23 devnull b = fileload(r, e);
471 056fe1ba 2003-11-23 devnull if(b == nil)
472 056fe1ba 2003-11-23 devnull return -1;
473 056fe1ba 2003-11-23 devnull vtblockput(b);
475 056fe1ba 2003-11-23 devnull return 0;
479 056fe1ba 2003-11-23 devnull vtfilesetentry(VtFile *r, VtEntry *e)
481 056fe1ba 2003-11-23 devnull VtBlock *b;
482 056fe1ba 2003-11-23 devnull VtEntry ee;
484 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
485 056fe1ba 2003-11-23 devnull b = fileload(r, &ee);
486 056fe1ba 2003-11-23 devnull if(b == nil)
487 056fe1ba 2003-11-23 devnull return -1;
488 056fe1ba 2003-11-23 devnull vtentrypack(e, b->data, r->offset % r->epb);
489 056fe1ba 2003-11-23 devnull vtblockput(b);
490 056fe1ba 2003-11-23 devnull return 0;
493 056fe1ba 2003-11-23 devnull static VtBlock *
494 056fe1ba 2003-11-23 devnull blockwalk(VtBlock *p, int index, VtCache *c, int mode, VtEntry *e)
496 056fe1ba 2003-11-23 devnull VtBlock *b;
497 056fe1ba 2003-11-23 devnull int type;
498 056fe1ba 2003-11-23 devnull uchar *score;
499 056fe1ba 2003-11-23 devnull VtEntry oe;
501 056fe1ba 2003-11-23 devnull switch(p->type){
502 056fe1ba 2003-11-23 devnull case VtDataType:
503 056fe1ba 2003-11-23 devnull assert(0);
504 056fe1ba 2003-11-23 devnull case VtDirType:
505 056fe1ba 2003-11-23 devnull type = e->type;
506 056fe1ba 2003-11-23 devnull score = e->score;
508 056fe1ba 2003-11-23 devnull default:
509 056fe1ba 2003-11-23 devnull type = p->type - 1;
510 056fe1ba 2003-11-23 devnull score = p->data+index*VtScoreSize;
513 056fe1ba 2003-11-23 devnull //print("walk from %V/%d ty %d to %V ty %d\n", p->score, index, p->type, score, type);
515 056fe1ba 2003-11-23 devnull if(mode == VtOWRITE && vtglobaltolocal(score) == NilBlock){
516 056fe1ba 2003-11-23 devnull b = vtcacheallocblock(c, type);
518 056fe1ba 2003-11-23 devnull goto HaveCopy;
520 056fe1ba 2003-11-23 devnull b = vtcacheglobal(c, score, type);
522 056fe1ba 2003-11-23 devnull if(b == nil || mode == VtOREAD)
523 056fe1ba 2003-11-23 devnull return b;
525 056fe1ba 2003-11-23 devnull if(vtglobaltolocal(b->score) != NilBlock)
526 056fe1ba 2003-11-23 devnull return b;
528 056fe1ba 2003-11-23 devnull oe = *e;
531 056fe1ba 2003-11-23 devnull * Copy on write.
533 056fe1ba 2003-11-23 devnull e->flags |= VtEntryLocal;
535 056fe1ba 2003-11-23 devnull b = vtblockcopy(b/*, e->tag, fs->ehi, fs->elo*/);
536 056fe1ba 2003-11-23 devnull if(b == nil)
537 056fe1ba 2003-11-23 devnull return nil;
539 056fe1ba 2003-11-23 devnull HaveCopy:
540 056fe1ba 2003-11-23 devnull if(p->type == VtDirType){
541 056fe1ba 2003-11-23 devnull memmove(e->score, b->score, VtScoreSize);
542 056fe1ba 2003-11-23 devnull vtentrypack(e, p->data, index);
544 056fe1ba 2003-11-23 devnull memmove(p->data+index*VtScoreSize, b->score, VtScoreSize);
546 056fe1ba 2003-11-23 devnull return b;
550 056fe1ba 2003-11-23 devnull * Change the depth of the VtFile r.
551 056fe1ba 2003-11-23 devnull * The entry e for r is contained in block p.
553 056fe1ba 2003-11-23 devnull static int
554 056fe1ba 2003-11-23 devnull growdepth(VtFile *r, VtBlock *p, VtEntry *e, int depth)
556 056fe1ba 2003-11-23 devnull VtBlock *b, *bb;
557 056fe1ba 2003-11-23 devnull VtEntry oe;
559 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
560 056fe1ba 2003-11-23 devnull assert(depth <= VtPointerDepth);
562 056fe1ba 2003-11-23 devnull b = vtcacheglobal(r->c, e->score, e->type);
563 056fe1ba 2003-11-23 devnull if(b == nil)
564 056fe1ba 2003-11-23 devnull return -1;
566 056fe1ba 2003-11-23 devnull oe = *e;
569 056fe1ba 2003-11-23 devnull * Keep adding layers until we get to the right depth
570 056fe1ba 2003-11-23 devnull * or an error occurs.
572 056fe1ba 2003-11-23 devnull while(DEPTH(e->type) < depth){
573 056fe1ba 2003-11-23 devnull bb = vtcacheallocblock(r->c, e->type+1);
574 056fe1ba 2003-11-23 devnull if(bb == nil)
576 056fe1ba 2003-11-23 devnull memmove(bb->data, b->score, VtScoreSize);
577 056fe1ba 2003-11-23 devnull memmove(e->score, bb->score, VtScoreSize);
578 056fe1ba 2003-11-23 devnull e->type++;
579 056fe1ba 2003-11-23 devnull e->flags |= VtEntryLocal;
580 056fe1ba 2003-11-23 devnull vtblockput(b);
584 056fe1ba 2003-11-23 devnull vtentrypack(e, p->data, r->offset % r->epb);
585 056fe1ba 2003-11-23 devnull vtblockput(b);
587 056fe1ba 2003-11-23 devnull if(DEPTH(e->type) == depth)
588 056fe1ba 2003-11-23 devnull return 0;
589 056fe1ba 2003-11-23 devnull return -1;
592 056fe1ba 2003-11-23 devnull static int
593 056fe1ba 2003-11-23 devnull shrinkdepth(VtFile *r, VtBlock *p, VtEntry *e, int depth)
595 056fe1ba 2003-11-23 devnull VtBlock *b, *nb, *ob, *rb;
596 056fe1ba 2003-11-23 devnull VtEntry oe;
598 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
599 056fe1ba 2003-11-23 devnull assert(depth <= VtPointerDepth);
601 056fe1ba 2003-11-23 devnull rb = vtcacheglobal(r->c, e->score, e->type);
602 056fe1ba 2003-11-23 devnull if(rb == nil)
603 056fe1ba 2003-11-23 devnull return 0;
606 056fe1ba 2003-11-23 devnull * Walk down to the new root block.
607 056fe1ba 2003-11-23 devnull * We may stop early, but something is better than nothing.
609 056fe1ba 2003-11-23 devnull oe = *e;
611 056fe1ba 2003-11-23 devnull ob = nil;
613 056fe1ba 2003-11-23 devnull for(; DEPTH(e->type) > depth; e->type--){
614 056fe1ba 2003-11-23 devnull nb = vtcacheglobal(r->c, b->data, e->type-1);
615 056fe1ba 2003-11-23 devnull if(nb == nil)
617 056fe1ba 2003-11-23 devnull if(ob!=nil && ob!=rb)
618 056fe1ba 2003-11-23 devnull vtblockput(ob);
623 056fe1ba 2003-11-23 devnull if(b == rb){
624 056fe1ba 2003-11-23 devnull vtblockput(rb);
625 056fe1ba 2003-11-23 devnull return 0;
629 056fe1ba 2003-11-23 devnull * Right now, e points at the root block rb, b is the new root block,
630 056fe1ba 2003-11-23 devnull * and ob points at b. To update:
632 056fe1ba 2003-11-23 devnull * (i) change e to point at b
633 056fe1ba 2003-11-23 devnull * (ii) zero the pointer ob -> b
634 056fe1ba 2003-11-23 devnull * (iii) free the root block
636 056fe1ba 2003-11-23 devnull * p (the block containing e) must be written before
637 056fe1ba 2003-11-23 devnull * anything else.
640 056fe1ba 2003-11-23 devnull /* (i) */
641 056fe1ba 2003-11-23 devnull memmove(e->score, b->score, VtScoreSize);
642 056fe1ba 2003-11-23 devnull vtentrypack(e, p->data, r->offset % r->epb);
644 056fe1ba 2003-11-23 devnull /* (ii) */
645 056fe1ba 2003-11-23 devnull memmove(ob->data, vtzeroscore, VtScoreSize);
647 056fe1ba 2003-11-23 devnull /* (iii) */
648 056fe1ba 2003-11-23 devnull vtblockput(rb);
649 056fe1ba 2003-11-23 devnull if(ob!=nil && ob!=rb)
650 056fe1ba 2003-11-23 devnull vtblockput(ob);
651 056fe1ba 2003-11-23 devnull vtblockput(b);
653 056fe1ba 2003-11-23 devnull if(DEPTH(e->type) == depth)
654 056fe1ba 2003-11-23 devnull return 0;
655 056fe1ba 2003-11-23 devnull return -1;
658 056fe1ba 2003-11-23 devnull static int
659 056fe1ba 2003-11-23 devnull mkindices(VtEntry *e, u32int bn, int *index)
661 056fe1ba 2003-11-23 devnull int i, np;
662 d23a617a 2004-03-15 devnull u32int obn;
664 d23a617a 2004-03-15 devnull obn = bn;
665 056fe1ba 2003-11-23 devnull memset(index, 0, VtPointerDepth*sizeof(int));
667 056fe1ba 2003-11-23 devnull np = e->psize/VtScoreSize;
668 056fe1ba 2003-11-23 devnull for(i=0; bn > 0; i++){
669 056fe1ba 2003-11-23 devnull if(i >= VtPointerDepth){
670 d23a617a 2004-03-15 devnull werrstr("bad address 0x%lux", (ulong)bn);
671 056fe1ba 2003-11-23 devnull return -1;
673 056fe1ba 2003-11-23 devnull index[i] = bn % np;
674 056fe1ba 2003-11-23 devnull bn /= np;
676 056fe1ba 2003-11-23 devnull return i;
679 056fe1ba 2003-11-23 devnull VtBlock *
680 056fe1ba 2003-11-23 devnull vtfileblock(VtFile *r, u32int bn, int mode)
682 056fe1ba 2003-11-23 devnull VtBlock *b, *bb;
683 056fe1ba 2003-11-23 devnull int index[VtPointerDepth+1];
684 056fe1ba 2003-11-23 devnull VtEntry e;
688 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
689 056fe1ba 2003-11-23 devnull assert(bn != NilBlock);
691 056fe1ba 2003-11-23 devnull b = fileload(r, &e);
692 056fe1ba 2003-11-23 devnull if(b == nil)
693 056fe1ba 2003-11-23 devnull return nil;
695 056fe1ba 2003-11-23 devnull i = mkindices(&e, bn, index);
696 056fe1ba 2003-11-23 devnull if(i < 0)
697 056fe1ba 2003-11-23 devnull return nil;
698 056fe1ba 2003-11-23 devnull if(i > DEPTH(e.type)){
699 056fe1ba 2003-11-23 devnull if(mode == VtOREAD){
700 d23a617a 2004-03-15 devnull werrstr("bad address 0x%lux", (ulong)bn);
701 056fe1ba 2003-11-23 devnull goto Err;
703 056fe1ba 2003-11-23 devnull index[i] = 0;
704 056fe1ba 2003-11-23 devnull if(growdepth(r, b, &e, i) < 0)
705 056fe1ba 2003-11-23 devnull goto Err;
708 056fe1ba 2003-11-23 devnull assert(b->type == VtDirType);
710 056fe1ba 2003-11-23 devnull index[DEPTH(e.type)] = r->offset % r->epb;
712 056fe1ba 2003-11-23 devnull /* mode for intermediate block */
713 056fe1ba 2003-11-23 devnull m = mode;
714 056fe1ba 2003-11-23 devnull if(m == VtOWRITE)
715 056fe1ba 2003-11-23 devnull m = VtORDWR;
717 056fe1ba 2003-11-23 devnull for(i=DEPTH(e.type); i>=0; i--){
718 056fe1ba 2003-11-23 devnull bb = blockwalk(b, index[i], r->c, i==0 ? mode : m, &e);
719 056fe1ba 2003-11-23 devnull if(bb == nil)
720 056fe1ba 2003-11-23 devnull goto Err;
721 056fe1ba 2003-11-23 devnull vtblockput(b);
724 056fe1ba 2003-11-23 devnull return b;
726 056fe1ba 2003-11-23 devnull vtblockput(b);
727 056fe1ba 2003-11-23 devnull return nil;
731 d23a617a 2004-03-15 devnull vtfileblockscore(VtFile *r, u32int bn, uchar score[VtScoreSize])
733 056fe1ba 2003-11-23 devnull VtBlock *b, *bb;
734 056fe1ba 2003-11-23 devnull int index[VtPointerDepth+1];
735 056fe1ba 2003-11-23 devnull VtEntry e;
738 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
739 056fe1ba 2003-11-23 devnull assert(bn != NilBlock);
741 056fe1ba 2003-11-23 devnull b = fileload(r, &e);
742 056fe1ba 2003-11-23 devnull if(b == nil)
743 056fe1ba 2003-11-23 devnull return -1;
745 056fe1ba 2003-11-23 devnull i = mkindices(&e, bn, index);
746 056fe1ba 2003-11-23 devnull if(i < 0){
747 056fe1ba 2003-11-23 devnull vtblockput(b);
748 056fe1ba 2003-11-23 devnull return -1;
750 056fe1ba 2003-11-23 devnull if(i > DEPTH(e.type)){
751 056fe1ba 2003-11-23 devnull memmove(score, vtzeroscore, VtScoreSize);
752 056fe1ba 2003-11-23 devnull vtblockput(b);
753 056fe1ba 2003-11-23 devnull return 0;
756 056fe1ba 2003-11-23 devnull index[DEPTH(e.type)] = r->offset % r->epb;
758 056fe1ba 2003-11-23 devnull for(i=DEPTH(e.type); i>=1; i--){
759 056fe1ba 2003-11-23 devnull bb = blockwalk(b, index[i], r->c, VtOREAD, &e);
760 056fe1ba 2003-11-23 devnull if(bb == nil)
761 056fe1ba 2003-11-23 devnull goto Err;
762 056fe1ba 2003-11-23 devnull vtblockput(b);
764 056fe1ba 2003-11-23 devnull if(memcmp(b->score, vtzeroscore, VtScoreSize) == 0)
768 056fe1ba 2003-11-23 devnull memmove(score, b->data+index[0]*VtScoreSize, VtScoreSize);
769 056fe1ba 2003-11-23 devnull vtblockput(b);
770 056fe1ba 2003-11-23 devnull return 0;
773 056fe1ba 2003-11-23 devnull fprint(2, "vtfileblockhash: %r\n");
774 056fe1ba 2003-11-23 devnull vtblockput(b);
775 056fe1ba 2003-11-23 devnull return -1;
779 056fe1ba 2003-11-23 devnull vtfileincref(VtFile *r)
781 056fe1ba 2003-11-23 devnull qlock(&r->lk);
782 056fe1ba 2003-11-23 devnull r->ref++;
783 056fe1ba 2003-11-23 devnull qunlock(&r->lk);
787 056fe1ba 2003-11-23 devnull vtfileclose(VtFile *r)
789 056fe1ba 2003-11-23 devnull if(r == nil)
791 056fe1ba 2003-11-23 devnull qlock(&r->lk);
792 056fe1ba 2003-11-23 devnull r->ref--;
793 056fe1ba 2003-11-23 devnull if(r->ref){
794 056fe1ba 2003-11-23 devnull qunlock(&r->lk);
797 056fe1ba 2003-11-23 devnull assert(r->ref == 0);
798 056fe1ba 2003-11-23 devnull qunlock(&r->lk);
799 056fe1ba 2003-11-23 devnull if(r->parent)
800 056fe1ba 2003-11-23 devnull vtfileclose(r->parent);
801 056fe1ba 2003-11-23 devnull memset(r, ~0, sizeof(*r));
802 056fe1ba 2003-11-23 devnull vtfree(r);
806 056fe1ba 2003-11-23 devnull * Retrieve the block containing the entry for r.
807 056fe1ba 2003-11-23 devnull * If a snapshot has happened, we might need
808 056fe1ba 2003-11-23 devnull * to get a new copy of the block. We avoid this
809 056fe1ba 2003-11-23 devnull * in the common case by caching the score for
810 056fe1ba 2003-11-23 devnull * the block and the last epoch in which it was valid.
812 056fe1ba 2003-11-23 devnull * We use r->mode to tell the difference between active
813 056fe1ba 2003-11-23 devnull * file system VtFiles (VtORDWR) and VtFiles for the
814 056fe1ba 2003-11-23 devnull * snapshot file system (VtOREAD).
816 056fe1ba 2003-11-23 devnull static VtBlock*
817 056fe1ba 2003-11-23 devnull fileloadblock(VtFile *r, int mode)
819 056fe1ba 2003-11-23 devnull char e[ERRMAX];
820 056fe1ba 2003-11-23 devnull u32int addr;
821 056fe1ba 2003-11-23 devnull VtBlock *b;
823 056fe1ba 2003-11-23 devnull switch(r->mode){
824 056fe1ba 2003-11-23 devnull default:
825 056fe1ba 2003-11-23 devnull assert(0);
826 056fe1ba 2003-11-23 devnull case VtORDWR:
827 056fe1ba 2003-11-23 devnull assert(r->mode == VtORDWR);
828 056fe1ba 2003-11-23 devnull if(r->local == 1){
829 056fe1ba 2003-11-23 devnull b = vtcacheglobal(r->c, r->score, VtDirType);
830 056fe1ba 2003-11-23 devnull if(b == nil)
831 056fe1ba 2003-11-23 devnull return nil;
832 056fe1ba 2003-11-23 devnull return b;
834 056fe1ba 2003-11-23 devnull assert(r->parent != nil);
835 056fe1ba 2003-11-23 devnull if(vtfilelock(r->parent, VtORDWR) < 0)
836 056fe1ba 2003-11-23 devnull return nil;
837 056fe1ba 2003-11-23 devnull b = vtfileblock(r->parent, r->offset/r->epb, VtORDWR);
838 056fe1ba 2003-11-23 devnull vtfileunlock(r->parent);
839 056fe1ba 2003-11-23 devnull if(b == nil)
840 056fe1ba 2003-11-23 devnull return nil;
841 056fe1ba 2003-11-23 devnull memmove(r->score, b->score, VtScoreSize);
842 056fe1ba 2003-11-23 devnull r->local = 1;
843 056fe1ba 2003-11-23 devnull return b;
845 056fe1ba 2003-11-23 devnull case VtOREAD:
846 056fe1ba 2003-11-23 devnull if(mode == VtORDWR){
847 056fe1ba 2003-11-23 devnull werrstr("read/write lock of read-only file");
848 056fe1ba 2003-11-23 devnull return nil;
850 056fe1ba 2003-11-23 devnull addr = vtglobaltolocal(r->score);
851 056fe1ba 2003-11-23 devnull if(addr == NilBlock)
852 056fe1ba 2003-11-23 devnull return vtcacheglobal(r->c, r->score, VtDirType);
854 056fe1ba 2003-11-23 devnull b = vtcachelocal(r->c, addr, VtDirType);
856 056fe1ba 2003-11-23 devnull return b;
859 056fe1ba 2003-11-23 devnull * If it failed because the epochs don't match, the block has been
860 056fe1ba 2003-11-23 devnull * archived and reclaimed. Rewalk from the parent and get the
861 056fe1ba 2003-11-23 devnull * new pointer. This can't happen in the VtORDWR case
862 056fe1ba 2003-11-23 devnull * above because blocks in the current epoch don't get
863 056fe1ba 2003-11-23 devnull * reclaimed. The fact that we're VtOREAD means we're
864 056fe1ba 2003-11-23 devnull * a snapshot. (Or else the file system is read-only, but then
865 056fe1ba 2003-11-23 devnull * the archiver isn't going around deleting blocks.)
867 056fe1ba 2003-11-23 devnull rerrstr(e, sizeof e);
868 056fe1ba 2003-11-23 devnull if(strcmp(e, ELabelMismatch) == 0){
869 056fe1ba 2003-11-23 devnull if(vtfilelock(r->parent, VtOREAD) < 0)
870 056fe1ba 2003-11-23 devnull return nil;
871 056fe1ba 2003-11-23 devnull b = vtfileblock(r->parent, r->offset/r->epb, VtOREAD);
872 056fe1ba 2003-11-23 devnull vtfileunlock(r->parent);
874 056fe1ba 2003-11-23 devnull fprint(2, "vtfilealloc: lost %V found %V\n",
875 056fe1ba 2003-11-23 devnull r->score, b->score);
876 056fe1ba 2003-11-23 devnull memmove(r->score, b->score, VtScoreSize);
877 056fe1ba 2003-11-23 devnull return b;
880 056fe1ba 2003-11-23 devnull return nil;
885 056fe1ba 2003-11-23 devnull vtfilelock(VtFile *r, int mode)
887 056fe1ba 2003-11-23 devnull VtBlock *b;
889 056fe1ba 2003-11-23 devnull if(mode == -1)
890 056fe1ba 2003-11-23 devnull mode = r->mode;
892 056fe1ba 2003-11-23 devnull b = fileloadblock(r, mode);
893 056fe1ba 2003-11-23 devnull if(b == nil)
894 056fe1ba 2003-11-23 devnull return -1;
896 056fe1ba 2003-11-23 devnull * The fact that we are holding b serves as the
897 056fe1ba 2003-11-23 devnull * lock entitling us to write to r->b.
899 056fe1ba 2003-11-23 devnull assert(r->b == nil);
900 056fe1ba 2003-11-23 devnull r->b = b;
901 056fe1ba 2003-11-23 devnull return 0;
905 056fe1ba 2003-11-23 devnull * Lock two (usually sibling) VtFiles. This needs special care
906 056fe1ba 2003-11-23 devnull * because the Entries for both vtFiles might be in the same block.
907 056fe1ba 2003-11-23 devnull * We also try to lock blocks in left-to-right order within the tree.
910 056fe1ba 2003-11-23 devnull vtfilelock2(VtFile *r, VtFile *rr, int mode)
912 056fe1ba 2003-11-23 devnull VtBlock *b, *bb;
914 056fe1ba 2003-11-23 devnull if(rr == nil)
915 056fe1ba 2003-11-23 devnull return vtfilelock(r, mode);
917 056fe1ba 2003-11-23 devnull if(mode == -1)
918 056fe1ba 2003-11-23 devnull mode = r->mode;
920 056fe1ba 2003-11-23 devnull if(r->parent==rr->parent && r->offset/r->epb == rr->offset/rr->epb){
921 056fe1ba 2003-11-23 devnull b = fileloadblock(r, mode);
922 056fe1ba 2003-11-23 devnull if(b == nil)
923 056fe1ba 2003-11-23 devnull return -1;
924 056fe1ba 2003-11-23 devnull vtblockduplock(b);
926 056fe1ba 2003-11-23 devnull }else if(r->parent==rr->parent || r->offset > rr->offset){
927 056fe1ba 2003-11-23 devnull bb = fileloadblock(rr, mode);
928 056fe1ba 2003-11-23 devnull b = fileloadblock(r, mode);
930 056fe1ba 2003-11-23 devnull b = fileloadblock(r, mode);
931 056fe1ba 2003-11-23 devnull bb = fileloadblock(rr, mode);
933 056fe1ba 2003-11-23 devnull if(b == nil || bb == nil){
935 056fe1ba 2003-11-23 devnull vtblockput(b);
937 056fe1ba 2003-11-23 devnull vtblockput(bb);
938 056fe1ba 2003-11-23 devnull return -1;
942 056fe1ba 2003-11-23 devnull * The fact that we are holding b and bb serves
943 056fe1ba 2003-11-23 devnull * as the lock entitling us to write to r->b and rr->b.
945 056fe1ba 2003-11-23 devnull r->b = b;
946 056fe1ba 2003-11-23 devnull rr->b = bb;
947 056fe1ba 2003-11-23 devnull return 0;
951 056fe1ba 2003-11-23 devnull vtfileunlock(VtFile *r)
953 056fe1ba 2003-11-23 devnull VtBlock *b;
955 056fe1ba 2003-11-23 devnull if(r->b == nil){
956 056fe1ba 2003-11-23 devnull fprint(2, "vtfileunlock: already unlocked\n");
957 056fe1ba 2003-11-23 devnull abort();
959 056fe1ba 2003-11-23 devnull b = r->b;
960 056fe1ba 2003-11-23 devnull r->b = nil;
961 056fe1ba 2003-11-23 devnull vtblockput(b);
964 056fe1ba 2003-11-23 devnull static VtBlock*
965 056fe1ba 2003-11-23 devnull fileload(VtFile *r, VtEntry *e)
967 056fe1ba 2003-11-23 devnull VtBlock *b;
969 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
970 056fe1ba 2003-11-23 devnull b = r->b;
971 056fe1ba 2003-11-23 devnull if(vtentryunpack(e, b->data, r->offset % r->epb) < 0)
972 056fe1ba 2003-11-23 devnull return nil;
973 056fe1ba 2003-11-23 devnull vtblockduplock(b);
974 056fe1ba 2003-11-23 devnull return b;
977 056fe1ba 2003-11-23 devnull static int
978 056fe1ba 2003-11-23 devnull sizetodepth(uvlong s, int psize, int dsize)
983 056fe1ba 2003-11-23 devnull /* determine pointer depth */
984 056fe1ba 2003-11-23 devnull np = psize/VtScoreSize;
985 056fe1ba 2003-11-23 devnull s = (s + dsize - 1)/dsize;
986 056fe1ba 2003-11-23 devnull for(d = 0; s > 1; d++)
987 056fe1ba 2003-11-23 devnull s = (s + np - 1)/np;
988 056fe1ba 2003-11-23 devnull return d;
992 056fe1ba 2003-11-23 devnull vtfileread(VtFile *f, void *data, long count, vlong offset)
994 056fe1ba 2003-11-23 devnull int frag;
995 056fe1ba 2003-11-23 devnull VtBlock *b;
996 056fe1ba 2003-11-23 devnull VtEntry e;
998 056fe1ba 2003-11-23 devnull assert(ISLOCKED(f));
1000 056fe1ba 2003-11-23 devnull vtfilegetentry(f, &e);
1001 056fe1ba 2003-11-23 devnull if(count == 0)
1002 056fe1ba 2003-11-23 devnull return 0;
1003 056fe1ba 2003-11-23 devnull if(count < 0 || offset < 0){
1004 056fe1ba 2003-11-23 devnull werrstr("vtfileread: bad offset or count");
1005 056fe1ba 2003-11-23 devnull return -1;
1007 056fe1ba 2003-11-23 devnull if(offset >= e.size)
1008 056fe1ba 2003-11-23 devnull return 0;
1010 056fe1ba 2003-11-23 devnull if(offset+count > e.size)
1011 056fe1ba 2003-11-23 devnull count = e.size - offset;
1013 056fe1ba 2003-11-23 devnull frag = offset % e.dsize;
1014 056fe1ba 2003-11-23 devnull if(frag+count > e.dsize)
1015 056fe1ba 2003-11-23 devnull count = e.dsize - frag;
1017 056fe1ba 2003-11-23 devnull b = vtfileblock(f, offset/e.dsize, VtOREAD);
1018 056fe1ba 2003-11-23 devnull if(b == nil)
1019 056fe1ba 2003-11-23 devnull return -1;
1021 056fe1ba 2003-11-23 devnull memmove(data, b->data+frag, count);
1022 056fe1ba 2003-11-23 devnull vtblockput(b);
1023 056fe1ba 2003-11-23 devnull return count;
1026 056fe1ba 2003-11-23 devnull static long
1027 056fe1ba 2003-11-23 devnull filewrite1(VtFile *f, void *data, long count, vlong offset)
1029 056fe1ba 2003-11-23 devnull int frag, m;
1030 056fe1ba 2003-11-23 devnull VtBlock *b;
1031 056fe1ba 2003-11-23 devnull VtEntry e;
1033 056fe1ba 2003-11-23 devnull vtfilegetentry(f, &e);
1034 056fe1ba 2003-11-23 devnull if(count < 0 || offset < 0){
1035 056fe1ba 2003-11-23 devnull werrstr("vtfilewrite: bad offset or count");
1036 056fe1ba 2003-11-23 devnull return -1;
1039 056fe1ba 2003-11-23 devnull frag = offset % e.dsize;
1040 056fe1ba 2003-11-23 devnull if(frag+count > e.dsize)
1041 056fe1ba 2003-11-23 devnull count = e.dsize - frag;
1043 056fe1ba 2003-11-23 devnull m = VtORDWR;
1044 056fe1ba 2003-11-23 devnull if(frag == 0 && count == e.dsize)
1045 056fe1ba 2003-11-23 devnull m = VtOWRITE;
1047 056fe1ba 2003-11-23 devnull b = vtfileblock(f, offset/e.dsize, m);
1048 056fe1ba 2003-11-23 devnull if(b == nil)
1049 056fe1ba 2003-11-23 devnull return -1;
1051 056fe1ba 2003-11-23 devnull memmove(b->data+frag, data, count);
1053 056fe1ba 2003-11-23 devnull if(offset+count > e.size){
1054 056fe1ba 2003-11-23 devnull vtfilegetentry(f, &e);
1055 056fe1ba 2003-11-23 devnull e.size = offset+count;
1056 056fe1ba 2003-11-23 devnull vtfilesetentry(f, &e);
1059 056fe1ba 2003-11-23 devnull vtblockput(b);
1060 056fe1ba 2003-11-23 devnull return count;
1064 056fe1ba 2003-11-23 devnull vtfilewrite(VtFile *f, void *data, long count, vlong offset)
1066 056fe1ba 2003-11-23 devnull long tot, m;
1068 056fe1ba 2003-11-23 devnull assert(ISLOCKED(f));
1070 056fe1ba 2003-11-23 devnull tot = 0;
1072 056fe1ba 2003-11-23 devnull while(tot < count){
1073 056fe1ba 2003-11-23 devnull m = filewrite1(f, (char*)data+tot, count-tot, offset+tot);
1074 056fe1ba 2003-11-23 devnull if(m <= 0)
1076 056fe1ba 2003-11-23 devnull tot += m;
1078 056fe1ba 2003-11-23 devnull if(tot==0)
1079 056fe1ba 2003-11-23 devnull return m;
1080 056fe1ba 2003-11-23 devnull return tot;
1083 056fe1ba 2003-11-23 devnull static int
1084 056fe1ba 2003-11-23 devnull flushblock(VtCache *c, VtBlock *bb, uchar score[VtScoreSize], int ppb, int epb,
1085 056fe1ba 2003-11-23 devnull int type)
1087 056fe1ba 2003-11-23 devnull u32int addr;
1088 056fe1ba 2003-11-23 devnull VtBlock *b;
1089 056fe1ba 2003-11-23 devnull VtEntry e;
1092 056fe1ba 2003-11-23 devnull addr = vtglobaltolocal(score);
1093 056fe1ba 2003-11-23 devnull if(addr == NilBlock)
1094 056fe1ba 2003-11-23 devnull return 0;
1096 056fe1ba 2003-11-23 devnull if(bb){
1097 056fe1ba 2003-11-23 devnull b = bb;
1098 056fe1ba 2003-11-23 devnull if(memcmp(b->score, score, VtScoreSize) != 0)
1099 056fe1ba 2003-11-23 devnull abort();
1101 056fe1ba 2003-11-23 devnull if((b = vtcachelocal(c, addr, type)) == nil)
1102 056fe1ba 2003-11-23 devnull return -1;
1104 056fe1ba 2003-11-23 devnull switch(type){
1105 056fe1ba 2003-11-23 devnull case VtDataType:
1108 056fe1ba 2003-11-23 devnull case VtDirType:
1109 056fe1ba 2003-11-23 devnull for(i=0; i<epb; i++){
1110 056fe1ba 2003-11-23 devnull if(vtentryunpack(&e, b->data, i) < 0)
1111 056fe1ba 2003-11-23 devnull goto Err;
1112 056fe1ba 2003-11-23 devnull if(flushblock(c, nil, e.score, e.psize/VtScoreSize, e.dsize/VtEntrySize,
1113 056fe1ba 2003-11-23 devnull e.type) < 0)
1114 056fe1ba 2003-11-23 devnull goto Err;
1118 056fe1ba 2003-11-23 devnull default: /* VtPointerTypeX */
1119 056fe1ba 2003-11-23 devnull for(i=0; i<ppb; i++){
1120 056fe1ba 2003-11-23 devnull if(flushblock(c, nil, b->data+VtScoreSize*i, ppb, epb, type-1) < 0)
1121 056fe1ba 2003-11-23 devnull goto Err;
1126 056fe1ba 2003-11-23 devnull if(vtblockwrite(b) < 0)
1127 056fe1ba 2003-11-23 devnull goto Err;
1128 056fe1ba 2003-11-23 devnull memmove(score, b->score, VtScoreSize);
1129 056fe1ba 2003-11-23 devnull if(b != bb)
1130 056fe1ba 2003-11-23 devnull vtblockput(b);
1131 056fe1ba 2003-11-23 devnull return 0;
1134 056fe1ba 2003-11-23 devnull if(b != bb)
1135 056fe1ba 2003-11-23 devnull vtblockput(b);
1136 056fe1ba 2003-11-23 devnull return -1;
1140 056fe1ba 2003-11-23 devnull vtfileflush(VtFile *f)
1142 056fe1ba 2003-11-23 devnull int ret;
1143 056fe1ba 2003-11-23 devnull VtBlock *b;
1144 056fe1ba 2003-11-23 devnull VtEntry e;
1146 056fe1ba 2003-11-23 devnull assert(ISLOCKED(f));
1147 056fe1ba 2003-11-23 devnull b = fileload(f, &e);
1148 056fe1ba 2003-11-23 devnull if(!(e.flags&VtEntryLocal)){
1149 056fe1ba 2003-11-23 devnull vtblockput(b);
1150 056fe1ba 2003-11-23 devnull return 0;
1153 056fe1ba 2003-11-23 devnull ret = flushblock(f->c, nil, e.score, e.psize/VtScoreSize, e.dsize/VtEntrySize,
1154 056fe1ba 2003-11-23 devnull e.type);
1155 056fe1ba 2003-11-23 devnull if(!ret){
1156 056fe1ba 2003-11-23 devnull vtblockput(b);
1157 056fe1ba 2003-11-23 devnull return -1;
1160 056fe1ba 2003-11-23 devnull vtentrypack(&e, b->data, f->offset % f->epb);
1161 056fe1ba 2003-11-23 devnull vtblockput(b);
1162 056fe1ba 2003-11-23 devnull return 0;
1166 056fe1ba 2003-11-23 devnull vtfileflushbefore(VtFile *r, u64int offset)
1168 056fe1ba 2003-11-23 devnull VtBlock *b, *bb;
1169 056fe1ba 2003-11-23 devnull VtEntry e;
1170 056fe1ba 2003-11-23 devnull int i, base, depth, ppb, epb, ok;
1171 056fe1ba 2003-11-23 devnull int index[VtPointerDepth+1], index1[VtPointerDepth+1], j, ret;
1172 056fe1ba 2003-11-23 devnull VtBlock *bi[VtPointerDepth+2];
1173 056fe1ba 2003-11-23 devnull uchar *score;
1175 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
1176 056fe1ba 2003-11-23 devnull if(offset == 0)
1177 056fe1ba 2003-11-23 devnull return 0;
1179 056fe1ba 2003-11-23 devnull b = fileload(r, &e);
1180 056fe1ba 2003-11-23 devnull if(b == nil)
1181 056fe1ba 2003-11-23 devnull return -1;
1183 056fe1ba 2003-11-23 devnull ret = -1;
1184 056fe1ba 2003-11-23 devnull memset(bi, 0, sizeof bi);
1185 056fe1ba 2003-11-23 devnull depth = DEPTH(e.type);
1186 056fe1ba 2003-11-23 devnull bi[depth+1] = b;
1187 056fe1ba 2003-11-23 devnull i = mkindices(&e, (offset-1)/e.dsize, index);
1188 056fe1ba 2003-11-23 devnull if(i < 0)
1189 056fe1ba 2003-11-23 devnull goto Err;
1190 056fe1ba 2003-11-23 devnull if(i > depth)
1191 056fe1ba 2003-11-23 devnull goto Err;
1192 056fe1ba 2003-11-23 devnull mkindices(&e, offset/e.dsize, index1);
1193 056fe1ba 2003-11-23 devnull ppb = e.psize / VtScoreSize;
1194 056fe1ba 2003-11-23 devnull epb = e.dsize / VtEntrySize;
1196 056fe1ba 2003-11-23 devnull index[depth] = r->offset % r->epb;
1197 056fe1ba 2003-11-23 devnull for(i=depth; i>=0; i--){
1198 056fe1ba 2003-11-23 devnull bb = blockwalk(b, index[i], r->c, VtORDWR, &e);
1199 056fe1ba 2003-11-23 devnull if(bb == nil)
1200 056fe1ba 2003-11-23 devnull goto Err;
1201 056fe1ba 2003-11-23 devnull bi[i] = bb;
1202 056fe1ba 2003-11-23 devnull b = bb;
1204 056fe1ba 2003-11-23 devnull ret = 0;
1206 056fe1ba 2003-11-23 devnull base = e.type&~VtTypeDepthMask;
1207 056fe1ba 2003-11-23 devnull for(i=0; i<depth; i++){
1208 056fe1ba 2003-11-23 devnull if(i == 0){
1209 056fe1ba 2003-11-23 devnull /* bottom: data or dir block */
1210 056fe1ba 2003-11-23 devnull ok = offset%e.dsize == 0;
1212 056fe1ba 2003-11-23 devnull /* middle: pointer blocks */
1213 056fe1ba 2003-11-23 devnull b = bi[i];
1215 056fe1ba 2003-11-23 devnull * flush everything up to the break
1217 056fe1ba 2003-11-23 devnull for(j=0; j<index[i-1]; j++)
1218 056fe1ba 2003-11-23 devnull if(flushblock(r->c, nil, b->data+j*VtScoreSize, ppb, epb, base+i-1) < 0)
1219 056fe1ba 2003-11-23 devnull goto Err;
1221 056fe1ba 2003-11-23 devnull * if the rest of the block is already flushed,
1222 056fe1ba 2003-11-23 devnull * we can flush the whole block.
1224 056fe1ba 2003-11-23 devnull ok = 1;
1225 056fe1ba 2003-11-23 devnull for(; j<ppb; j++)
1226 056fe1ba 2003-11-23 devnull if(vtglobaltolocal(b->data+j*VtScoreSize) != NilBlock)
1227 056fe1ba 2003-11-23 devnull ok = 0;
1229 056fe1ba 2003-11-23 devnull if(ok){
1230 056fe1ba 2003-11-23 devnull if(i == depth)
1231 056fe1ba 2003-11-23 devnull score = e.score;
1233 056fe1ba 2003-11-23 devnull score = bi[i+1]->data+index[i]*VtScoreSize;
1234 056fe1ba 2003-11-23 devnull if(flushblock(r->c, bi[i], score, ppb, epb, base+i) < 0)
1235 056fe1ba 2003-11-23 devnull goto Err;
1240 056fe1ba 2003-11-23 devnull /* top: entry. do this always so that the score is up-to-date */
1241 056fe1ba 2003-11-23 devnull vtentrypack(&e, bi[depth+1]->data, index[depth]);
1242 056fe1ba 2003-11-23 devnull for(i=0; i<nelem(bi); i++)
1243 056fe1ba 2003-11-23 devnull if(bi[i])
1244 056fe1ba 2003-11-23 devnull vtblockput(bi[i]);
1245 056fe1ba 2003-11-23 devnull return ret;
