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>
19 0dc99502 2005-01-14 devnull #define MaxBlock (1UL<<31)
21 056fe1ba 2003-11-23 devnull static char ENotDir[] = "walk in non-directory";
22 056fe1ba 2003-11-23 devnull static char ETooBig[] = "file too big";
23 e5d47e6e 2004-12-28 devnull /* static char EBadAddr[] = "bad address"; */
24 056fe1ba 2003-11-23 devnull static char ELabelMismatch[] = "label mismatch";
26 056fe1ba 2003-11-23 devnull static int sizetodepth(uvlong s, int psize, int dsize);
27 056fe1ba 2003-11-23 devnull static VtBlock *fileload(VtFile *r, VtEntry *e);
28 056fe1ba 2003-11-23 devnull static int shrinkdepth(VtFile*, VtBlock*, VtEntry*, int);
29 056fe1ba 2003-11-23 devnull static int shrinksize(VtFile*, VtEntry*, uvlong);
30 056fe1ba 2003-11-23 devnull static int growdepth(VtFile*, VtBlock*, VtEntry*, int);
32 056fe1ba 2003-11-23 devnull #define ISLOCKED(r) ((r)->b != nil)
33 056fe1ba 2003-11-23 devnull #define DEPTH(t) ((t)&VtTypeDepthMask)
35 056fe1ba 2003-11-23 devnull static VtFile *
36 056fe1ba 2003-11-23 devnull vtfilealloc(VtCache *c, VtBlock *b, VtFile *p, u32int offset, int mode)
39 056fe1ba 2003-11-23 devnull VtEntry e;
40 056fe1ba 2003-11-23 devnull VtFile *r;
42 056fe1ba 2003-11-23 devnull assert(p==nil || ISLOCKED(p));
44 056fe1ba 2003-11-23 devnull if(p == nil){
45 056fe1ba 2003-11-23 devnull assert(offset == 0);
48 056fe1ba 2003-11-23 devnull epb = p->dsize / VtEntrySize;
50 23fb2edb 2005-07-24 devnull if(b->type != VtDirType){
51 23fb2edb 2005-07-24 devnull werrstr("bad block type %#uo", b->type);
52 23fb2edb 2005-07-24 devnull return nil;
56 056fe1ba 2003-11-23 devnull * a non-active entry is the only thing that
57 056fe1ba 2003-11-23 devnull * can legitimately happen here. all the others
58 056fe1ba 2003-11-23 devnull * get prints.
60 056fe1ba 2003-11-23 devnull if(vtentryunpack(&e, b->data, offset % epb) < 0){
61 23fb2edb 2005-07-24 devnull fprint(2, "vtentryunpack failed: %r (%.*H)\n", VtEntrySize, b->data+VtEntrySize*(offset%epb));
62 23fb2edb 2005-07-24 devnull return nil;
64 056fe1ba 2003-11-23 devnull if(!(e.flags & VtEntryActive)){
65 23fb2edb 2005-07-24 devnull werrstr("entry not active");
66 23fb2edb 2005-07-24 devnull return nil;
69 056fe1ba 2003-11-23 devnull if(DEPTH(e.type) < sizetodepth(e.size, e.psize, e.dsize)){
70 056fe1ba 2003-11-23 devnull fprint(2, "depth %ud size %llud psize %ud dsize %ud\n",
71 056fe1ba 2003-11-23 devnull DEPTH(e.type), e.size, e.psize, e.dsize);
72 23fb2edb 2005-07-24 devnull werrstr("bad depth");
73 23fb2edb 2005-07-24 devnull return nil;
76 056fe1ba 2003-11-23 devnull r = vtmallocz(sizeof(VtFile));
77 056fe1ba 2003-11-23 devnull r->c = c;
78 75d04888 2009-05-25 rsc r->bsize = b->size;
79 056fe1ba 2003-11-23 devnull r->mode = mode;
80 056fe1ba 2003-11-23 devnull r->dsize = e.dsize;
81 c1e6f642 2005-07-13 devnull r->psize = e.psize;
82 056fe1ba 2003-11-23 devnull r->gen = e.gen;
83 d23a617a 2004-03-15 devnull r->dir = (e.type & VtTypeBaseMask) == VtDirType;
84 056fe1ba 2003-11-23 devnull r->ref = 1;
85 056fe1ba 2003-11-23 devnull r->parent = p;
87 056fe1ba 2003-11-23 devnull qlock(&p->lk);
88 056fe1ba 2003-11-23 devnull assert(mode == VtOREAD || p->mode == VtORDWR);
89 056fe1ba 2003-11-23 devnull p->ref++;
90 056fe1ba 2003-11-23 devnull qunlock(&p->lk);
92 7cb74894 2004-06-17 devnull assert(b->addr != NilBlock);
93 7cb74894 2004-06-17 devnull r->local = 1;
95 056fe1ba 2003-11-23 devnull memmove(r->score, b->score, VtScoreSize);
96 056fe1ba 2003-11-23 devnull r->offset = offset;
97 056fe1ba 2003-11-23 devnull r->epb = epb;
99 056fe1ba 2003-11-23 devnull return r;
102 056fe1ba 2003-11-23 devnull VtFile *
103 056fe1ba 2003-11-23 devnull vtfileroot(VtCache *c, u32int addr, int mode)
105 056fe1ba 2003-11-23 devnull VtFile *r;
106 056fe1ba 2003-11-23 devnull VtBlock *b;
108 056fe1ba 2003-11-23 devnull b = vtcachelocal(c, addr, VtDirType);
109 056fe1ba 2003-11-23 devnull if(b == nil)
110 056fe1ba 2003-11-23 devnull return nil;
111 056fe1ba 2003-11-23 devnull r = vtfilealloc(c, b, nil, 0, mode);
112 056fe1ba 2003-11-23 devnull vtblockput(b);
113 056fe1ba 2003-11-23 devnull return r;
117 056fe1ba 2003-11-23 devnull vtfileopenroot(VtCache *c, VtEntry *e)
119 056fe1ba 2003-11-23 devnull VtBlock *b;
120 056fe1ba 2003-11-23 devnull VtFile *f;
122 75d04888 2009-05-25 rsc b = vtcacheallocblock(c, VtDirType, VtEntrySize);
123 056fe1ba 2003-11-23 devnull if(b == nil)
124 056fe1ba 2003-11-23 devnull return nil;
126 056fe1ba 2003-11-23 devnull vtentrypack(e, b->data, 0);
127 056fe1ba 2003-11-23 devnull f = vtfilealloc(c, b, nil, 0, VtORDWR);
128 056fe1ba 2003-11-23 devnull vtblockput(b);
129 056fe1ba 2003-11-23 devnull return f;
132 056fe1ba 2003-11-23 devnull VtFile *
133 056fe1ba 2003-11-23 devnull vtfilecreateroot(VtCache *c, int psize, int dsize, int type)
135 056fe1ba 2003-11-23 devnull VtEntry e;
137 056fe1ba 2003-11-23 devnull memset(&e, 0, sizeof e);
138 056fe1ba 2003-11-23 devnull e.flags = VtEntryActive;
139 056fe1ba 2003-11-23 devnull e.psize = psize;
140 056fe1ba 2003-11-23 devnull e.dsize = dsize;
141 d23a617a 2004-03-15 devnull e.type = type;
142 056fe1ba 2003-11-23 devnull memmove(e.score, vtzeroscore, VtScoreSize);
144 056fe1ba 2003-11-23 devnull return vtfileopenroot(c, &e);
147 056fe1ba 2003-11-23 devnull VtFile *
148 056fe1ba 2003-11-23 devnull vtfileopen(VtFile *r, u32int offset, int mode)
150 056fe1ba 2003-11-23 devnull ulong bn;
151 056fe1ba 2003-11-23 devnull VtBlock *b;
153 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
154 056fe1ba 2003-11-23 devnull if(!r->dir){
155 056fe1ba 2003-11-23 devnull werrstr(ENotDir);
156 056fe1ba 2003-11-23 devnull return nil;
159 056fe1ba 2003-11-23 devnull bn = offset/(r->dsize/VtEntrySize);
161 056fe1ba 2003-11-23 devnull b = vtfileblock(r, bn, mode);
162 056fe1ba 2003-11-23 devnull if(b == nil)
163 056fe1ba 2003-11-23 devnull return nil;
164 056fe1ba 2003-11-23 devnull r = vtfilealloc(r->c, b, r, offset, mode);
165 056fe1ba 2003-11-23 devnull vtblockput(b);
166 056fe1ba 2003-11-23 devnull return r;
170 3082404e 2005-07-13 devnull vtfilecreate(VtFile *r, int psize, int dsize, int type)
172 23fb2edb 2005-07-24 devnull return _vtfilecreate(r, -1, psize, dsize, type);
176 23fb2edb 2005-07-24 devnull _vtfilecreate(VtFile *r, int o, int psize, int dsize, int type)
179 056fe1ba 2003-11-23 devnull VtBlock *b;
180 056fe1ba 2003-11-23 devnull u32int bn, size;
181 056fe1ba 2003-11-23 devnull VtEntry e;
182 056fe1ba 2003-11-23 devnull int epb;
183 056fe1ba 2003-11-23 devnull VtFile *rr;
184 23fb2edb 2005-07-24 devnull u32int offset;
186 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
187 3082404e 2005-07-13 devnull assert(type == VtDirType || type == VtDataType);
189 056fe1ba 2003-11-23 devnull if(!r->dir){
190 056fe1ba 2003-11-23 devnull werrstr(ENotDir);
191 056fe1ba 2003-11-23 devnull return nil;
194 056fe1ba 2003-11-23 devnull epb = r->dsize/VtEntrySize;
196 056fe1ba 2003-11-23 devnull size = vtfilegetdirsize(r);
198 056fe1ba 2003-11-23 devnull * look at a random block to see if we can find an empty entry
200 23fb2edb 2005-07-24 devnull if(o == -1){
201 23fb2edb 2005-07-24 devnull offset = lnrand(size+1);
202 23fb2edb 2005-07-24 devnull offset -= offset % epb;
204 23fb2edb 2005-07-24 devnull offset = o;
206 056fe1ba 2003-11-23 devnull /* try the given block and then try the last block */
207 056fe1ba 2003-11-23 devnull for(;;){
208 056fe1ba 2003-11-23 devnull bn = offset/epb;
209 056fe1ba 2003-11-23 devnull b = vtfileblock(r, bn, VtORDWR);
210 056fe1ba 2003-11-23 devnull if(b == nil)
211 056fe1ba 2003-11-23 devnull return nil;
212 056fe1ba 2003-11-23 devnull for(i=offset%r->epb; i<epb; i++){
213 056fe1ba 2003-11-23 devnull if(vtentryunpack(&e, b->data, i) < 0)
214 056fe1ba 2003-11-23 devnull continue;
215 056fe1ba 2003-11-23 devnull if((e.flags&VtEntryActive) == 0 && e.gen != ~0)
216 056fe1ba 2003-11-23 devnull goto Found;
218 056fe1ba 2003-11-23 devnull vtblockput(b);
219 056fe1ba 2003-11-23 devnull if(offset == size){
220 056fe1ba 2003-11-23 devnull fprint(2, "vtfilecreate: cannot happen\n");
221 056fe1ba 2003-11-23 devnull werrstr("vtfilecreate: cannot happen");
222 056fe1ba 2003-11-23 devnull return nil;
224 056fe1ba 2003-11-23 devnull offset = size;
228 056fe1ba 2003-11-23 devnull /* found an entry - gen already set */
229 056fe1ba 2003-11-23 devnull e.psize = psize;
230 056fe1ba 2003-11-23 devnull e.dsize = dsize;
231 056fe1ba 2003-11-23 devnull e.flags = VtEntryActive;
232 3082404e 2005-07-13 devnull e.type = type;
233 056fe1ba 2003-11-23 devnull e.size = 0;
234 056fe1ba 2003-11-23 devnull memmove(e.score, vtzeroscore, VtScoreSize);
235 056fe1ba 2003-11-23 devnull vtentrypack(&e, b->data, i);
237 056fe1ba 2003-11-23 devnull offset = bn*epb + i;
238 056fe1ba 2003-11-23 devnull if(offset+1 > size){
239 056fe1ba 2003-11-23 devnull if(vtfilesetdirsize(r, offset+1) < 0){
240 056fe1ba 2003-11-23 devnull vtblockput(b);
241 056fe1ba 2003-11-23 devnull return nil;
245 056fe1ba 2003-11-23 devnull rr = vtfilealloc(r->c, b, r, offset, VtORDWR);
246 056fe1ba 2003-11-23 devnull vtblockput(b);
247 056fe1ba 2003-11-23 devnull return rr;
250 056fe1ba 2003-11-23 devnull static int
251 056fe1ba 2003-11-23 devnull vtfilekill(VtFile *r, int doremove)
253 056fe1ba 2003-11-23 devnull VtEntry e;
254 056fe1ba 2003-11-23 devnull VtBlock *b;
256 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
257 056fe1ba 2003-11-23 devnull b = fileload(r, &e);
258 056fe1ba 2003-11-23 devnull if(b == nil)
259 056fe1ba 2003-11-23 devnull return -1;
261 056fe1ba 2003-11-23 devnull if(doremove==0 && e.size == 0){
262 056fe1ba 2003-11-23 devnull /* already truncated */
263 056fe1ba 2003-11-23 devnull vtblockput(b);
264 056fe1ba 2003-11-23 devnull return 0;
267 056fe1ba 2003-11-23 devnull if(doremove){
268 056fe1ba 2003-11-23 devnull if(e.gen != ~0)
269 056fe1ba 2003-11-23 devnull e.gen++;
270 056fe1ba 2003-11-23 devnull e.dsize = 0;
271 056fe1ba 2003-11-23 devnull e.psize = 0;
272 056fe1ba 2003-11-23 devnull e.flags = 0;
274 056fe1ba 2003-11-23 devnull e.flags &= ~VtEntryLocal;
275 056fe1ba 2003-11-23 devnull e.type = 0;
276 056fe1ba 2003-11-23 devnull e.size = 0;
277 056fe1ba 2003-11-23 devnull memmove(e.score, vtzeroscore, VtScoreSize);
278 056fe1ba 2003-11-23 devnull vtentrypack(&e, b->data, r->offset % r->epb);
279 056fe1ba 2003-11-23 devnull vtblockput(b);
281 056fe1ba 2003-11-23 devnull if(doremove){
282 056fe1ba 2003-11-23 devnull vtfileunlock(r);
283 056fe1ba 2003-11-23 devnull vtfileclose(r);
286 056fe1ba 2003-11-23 devnull return 0;
290 056fe1ba 2003-11-23 devnull vtfileremove(VtFile *r)
292 056fe1ba 2003-11-23 devnull return vtfilekill(r, 1);
296 056fe1ba 2003-11-23 devnull vtfiletruncate(VtFile *r)
298 056fe1ba 2003-11-23 devnull return vtfilekill(r, 0);
302 056fe1ba 2003-11-23 devnull vtfilegetsize(VtFile *r)
304 056fe1ba 2003-11-23 devnull VtEntry e;
305 056fe1ba 2003-11-23 devnull VtBlock *b;
307 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
308 056fe1ba 2003-11-23 devnull b = fileload(r, &e);
309 056fe1ba 2003-11-23 devnull if(b == nil)
310 056fe1ba 2003-11-23 devnull return ~(uvlong)0;
311 056fe1ba 2003-11-23 devnull vtblockput(b);
313 056fe1ba 2003-11-23 devnull return e.size;
316 056fe1ba 2003-11-23 devnull static int
317 056fe1ba 2003-11-23 devnull shrinksize(VtFile *r, VtEntry *e, uvlong size)
319 75d04888 2009-05-25 rsc int i, depth, bsiz, type, isdir, ppb;
320 056fe1ba 2003-11-23 devnull uvlong ptrsz;
321 056fe1ba 2003-11-23 devnull uchar score[VtScoreSize];
322 056fe1ba 2003-11-23 devnull VtBlock *b;
324 75d04888 2009-05-25 rsc b = vtcacheglobal(r->c, e->score, e->type, r->dsize);
325 056fe1ba 2003-11-23 devnull if(b == nil)
326 056fe1ba 2003-11-23 devnull return -1;
328 056fe1ba 2003-11-23 devnull ptrsz = e->dsize;
329 056fe1ba 2003-11-23 devnull ppb = e->psize/VtScoreSize;
330 056fe1ba 2003-11-23 devnull type = e->type;
331 056fe1ba 2003-11-23 devnull depth = DEPTH(type);
332 056fe1ba 2003-11-23 devnull for(i=0; i+1<depth; i++)
333 056fe1ba 2003-11-23 devnull ptrsz *= ppb;
335 056fe1ba 2003-11-23 devnull isdir = r->dir;
336 589ae3a3 2008-10-26 rsc while(DEPTH(type) > 0){
337 056fe1ba 2003-11-23 devnull if(b->addr == NilBlock){
338 056fe1ba 2003-11-23 devnull /* not worth copying the block just so we can zero some of it */
339 056fe1ba 2003-11-23 devnull vtblockput(b);
340 056fe1ba 2003-11-23 devnull return -1;
344 056fe1ba 2003-11-23 devnull * invariant: each pointer in the tree rooted at b accounts for ptrsz bytes
347 056fe1ba 2003-11-23 devnull /* zero the pointers to unnecessary blocks */
348 056fe1ba 2003-11-23 devnull i = (size+ptrsz-1)/ptrsz;
349 056fe1ba 2003-11-23 devnull for(; i<ppb; i++)
350 056fe1ba 2003-11-23 devnull memmove(b->data+i*VtScoreSize, vtzeroscore, VtScoreSize);
352 056fe1ba 2003-11-23 devnull /* recurse (go around again) on the partially necessary block */
353 056fe1ba 2003-11-23 devnull i = size/ptrsz;
354 056fe1ba 2003-11-23 devnull size = size%ptrsz;
355 056fe1ba 2003-11-23 devnull if(size == 0){
356 056fe1ba 2003-11-23 devnull vtblockput(b);
357 056fe1ba 2003-11-23 devnull return 0;
359 056fe1ba 2003-11-23 devnull ptrsz /= ppb;
361 056fe1ba 2003-11-23 devnull memmove(score, b->data+i*VtScoreSize, VtScoreSize);
362 056fe1ba 2003-11-23 devnull vtblockput(b);
363 75d04888 2009-05-25 rsc if(type == VtDataType || type == VtDirType)
364 75d04888 2009-05-25 rsc bsiz = r->dsize;
366 75d04888 2009-05-25 rsc bsiz = r->psize;
367 75d04888 2009-05-25 rsc b = vtcacheglobal(r->c, score, type, bsiz);
368 056fe1ba 2003-11-23 devnull if(b == nil)
369 056fe1ba 2003-11-23 devnull return -1;
372 056fe1ba 2003-11-23 devnull if(b->addr == NilBlock){
373 056fe1ba 2003-11-23 devnull vtblockput(b);
374 056fe1ba 2003-11-23 devnull return -1;
378 056fe1ba 2003-11-23 devnull * No one ever truncates BtDir blocks.
380 056fe1ba 2003-11-23 devnull if(depth==0 && !isdir && e->dsize > size)
381 056fe1ba 2003-11-23 devnull memset(b->data+size, 0, e->dsize-size);
382 056fe1ba 2003-11-23 devnull vtblockput(b);
383 056fe1ba 2003-11-23 devnull return 0;
387 3f6a501b 2005-12-30 devnull vtfilesetsize(VtFile *r, u64int size)
389 056fe1ba 2003-11-23 devnull int depth, edepth;
390 056fe1ba 2003-11-23 devnull VtEntry e;
391 056fe1ba 2003-11-23 devnull VtBlock *b;
393 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
394 056fe1ba 2003-11-23 devnull if(size == 0)
395 056fe1ba 2003-11-23 devnull return vtfiletruncate(r);
397 056fe1ba 2003-11-23 devnull if(size > VtMaxFileSize || size > ((uvlong)MaxBlock)*r->dsize){
398 056fe1ba 2003-11-23 devnull werrstr(ETooBig);
399 056fe1ba 2003-11-23 devnull return -1;
402 056fe1ba 2003-11-23 devnull b = fileload(r, &e);
403 056fe1ba 2003-11-23 devnull if(b == nil)
404 056fe1ba 2003-11-23 devnull return -1;
406 056fe1ba 2003-11-23 devnull /* quick out */
407 056fe1ba 2003-11-23 devnull if(e.size == size){
408 056fe1ba 2003-11-23 devnull vtblockput(b);
409 056fe1ba 2003-11-23 devnull return 0;
412 056fe1ba 2003-11-23 devnull depth = sizetodepth(size, e.psize, e.dsize);
413 056fe1ba 2003-11-23 devnull edepth = DEPTH(e.type);
414 056fe1ba 2003-11-23 devnull if(depth < edepth){
415 056fe1ba 2003-11-23 devnull if(shrinkdepth(r, b, &e, depth) < 0){
416 056fe1ba 2003-11-23 devnull vtblockput(b);
417 056fe1ba 2003-11-23 devnull return -1;
419 056fe1ba 2003-11-23 devnull }else if(depth > edepth){
420 056fe1ba 2003-11-23 devnull if(growdepth(r, b, &e, depth) < 0){
421 056fe1ba 2003-11-23 devnull vtblockput(b);
422 056fe1ba 2003-11-23 devnull return -1;
426 056fe1ba 2003-11-23 devnull if(size < e.size)
427 056fe1ba 2003-11-23 devnull shrinksize(r, &e, size);
429 056fe1ba 2003-11-23 devnull e.size = size;
430 056fe1ba 2003-11-23 devnull vtentrypack(&e, b->data, r->offset % r->epb);
431 056fe1ba 2003-11-23 devnull vtblockput(b);
433 056fe1ba 2003-11-23 devnull return 0;
437 056fe1ba 2003-11-23 devnull vtfilesetdirsize(VtFile *r, u32int ds)
439 056fe1ba 2003-11-23 devnull uvlong size;
440 056fe1ba 2003-11-23 devnull int epb;
442 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
443 056fe1ba 2003-11-23 devnull epb = r->dsize/VtEntrySize;
445 056fe1ba 2003-11-23 devnull size = (uvlong)r->dsize*(ds/epb);
446 056fe1ba 2003-11-23 devnull size += VtEntrySize*(ds%epb);
447 056fe1ba 2003-11-23 devnull return vtfilesetsize(r, size);
451 056fe1ba 2003-11-23 devnull vtfilegetdirsize(VtFile *r)
453 056fe1ba 2003-11-23 devnull ulong ds;
454 056fe1ba 2003-11-23 devnull uvlong size;
455 056fe1ba 2003-11-23 devnull int epb;
457 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
458 056fe1ba 2003-11-23 devnull epb = r->dsize/VtEntrySize;
460 056fe1ba 2003-11-23 devnull size = vtfilegetsize(r);
461 056fe1ba 2003-11-23 devnull ds = epb*(size/r->dsize);
462 056fe1ba 2003-11-23 devnull ds += (size%r->dsize)/VtEntrySize;
463 056fe1ba 2003-11-23 devnull return ds;
467 056fe1ba 2003-11-23 devnull vtfilegetentry(VtFile *r, VtEntry *e)
469 056fe1ba 2003-11-23 devnull VtBlock *b;
471 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
472 056fe1ba 2003-11-23 devnull b = fileload(r, e);
473 056fe1ba 2003-11-23 devnull if(b == nil)
474 056fe1ba 2003-11-23 devnull return -1;
475 056fe1ba 2003-11-23 devnull vtblockput(b);
477 056fe1ba 2003-11-23 devnull return 0;
481 056fe1ba 2003-11-23 devnull vtfilesetentry(VtFile *r, VtEntry *e)
483 056fe1ba 2003-11-23 devnull VtBlock *b;
484 056fe1ba 2003-11-23 devnull VtEntry ee;
486 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
487 056fe1ba 2003-11-23 devnull b = fileload(r, &ee);
488 056fe1ba 2003-11-23 devnull if(b == nil)
489 056fe1ba 2003-11-23 devnull return -1;
490 056fe1ba 2003-11-23 devnull vtentrypack(e, b->data, r->offset % r->epb);
491 056fe1ba 2003-11-23 devnull vtblockput(b);
492 056fe1ba 2003-11-23 devnull return 0;
495 056fe1ba 2003-11-23 devnull static VtBlock *
496 75d04888 2009-05-25 rsc blockwalk(VtFile *r, VtBlock *p, int index, VtCache *c, int mode, VtEntry *e)
498 056fe1ba 2003-11-23 devnull VtBlock *b;
499 75d04888 2009-05-25 rsc int type, size;
500 056fe1ba 2003-11-23 devnull uchar *score;
501 056fe1ba 2003-11-23 devnull VtEntry oe;
503 056fe1ba 2003-11-23 devnull switch(p->type){
504 056fe1ba 2003-11-23 devnull case VtDataType:
505 056fe1ba 2003-11-23 devnull assert(0);
506 056fe1ba 2003-11-23 devnull case VtDirType:
507 056fe1ba 2003-11-23 devnull type = e->type;
508 056fe1ba 2003-11-23 devnull score = e->score;
510 056fe1ba 2003-11-23 devnull default:
511 056fe1ba 2003-11-23 devnull type = p->type - 1;
512 056fe1ba 2003-11-23 devnull score = p->data+index*VtScoreSize;
515 cbeb0b26 2006-04-01 devnull /*print("walk from %V/%d ty %d to %V ty %d\n", p->score, index, p->type, score, type); */
517 75d04888 2009-05-25 rsc if(type == VtDirType || type == VtDataType)
518 75d04888 2009-05-25 rsc size = r->dsize;
520 75d04888 2009-05-25 rsc size = r->psize;
521 056fe1ba 2003-11-23 devnull if(mode == VtOWRITE && vtglobaltolocal(score) == NilBlock){
522 75d04888 2009-05-25 rsc b = vtcacheallocblock(c, type, size);
524 056fe1ba 2003-11-23 devnull goto HaveCopy;
526 75d04888 2009-05-25 rsc b = vtcacheglobal(c, score, type, size);
528 056fe1ba 2003-11-23 devnull if(b == nil || mode == VtOREAD)
529 056fe1ba 2003-11-23 devnull return b;
531 056fe1ba 2003-11-23 devnull if(vtglobaltolocal(b->score) != NilBlock)
532 056fe1ba 2003-11-23 devnull return b;
534 056fe1ba 2003-11-23 devnull oe = *e;
537 056fe1ba 2003-11-23 devnull * Copy on write.
539 056fe1ba 2003-11-23 devnull e->flags |= VtEntryLocal;
541 056fe1ba 2003-11-23 devnull b = vtblockcopy(b/*, e->tag, fs->ehi, fs->elo*/);
542 056fe1ba 2003-11-23 devnull if(b == nil)
543 056fe1ba 2003-11-23 devnull return nil;
545 056fe1ba 2003-11-23 devnull HaveCopy:
546 056fe1ba 2003-11-23 devnull if(p->type == VtDirType){
547 056fe1ba 2003-11-23 devnull memmove(e->score, b->score, VtScoreSize);
548 056fe1ba 2003-11-23 devnull vtentrypack(e, p->data, index);
550 056fe1ba 2003-11-23 devnull memmove(p->data+index*VtScoreSize, b->score, VtScoreSize);
552 056fe1ba 2003-11-23 devnull return b;
556 056fe1ba 2003-11-23 devnull * Change the depth of the VtFile r.
557 056fe1ba 2003-11-23 devnull * The entry e for r is contained in block p.
559 056fe1ba 2003-11-23 devnull static int
560 056fe1ba 2003-11-23 devnull growdepth(VtFile *r, VtBlock *p, VtEntry *e, int depth)
562 056fe1ba 2003-11-23 devnull VtBlock *b, *bb;
563 056fe1ba 2003-11-23 devnull VtEntry oe;
565 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
566 056fe1ba 2003-11-23 devnull assert(depth <= VtPointerDepth);
568 75d04888 2009-05-25 rsc b = vtcacheglobal(r->c, e->score, e->type, r->dsize);
569 056fe1ba 2003-11-23 devnull if(b == nil)
570 056fe1ba 2003-11-23 devnull return -1;
572 056fe1ba 2003-11-23 devnull oe = *e;
575 056fe1ba 2003-11-23 devnull * Keep adding layers until we get to the right depth
576 056fe1ba 2003-11-23 devnull * or an error occurs.
578 056fe1ba 2003-11-23 devnull while(DEPTH(e->type) < depth){
579 75d04888 2009-05-25 rsc bb = vtcacheallocblock(r->c, e->type+1, r->psize);
580 056fe1ba 2003-11-23 devnull if(bb == nil)
582 056fe1ba 2003-11-23 devnull memmove(bb->data, b->score, VtScoreSize);
583 056fe1ba 2003-11-23 devnull memmove(e->score, bb->score, VtScoreSize);
584 056fe1ba 2003-11-23 devnull e->type++;
585 056fe1ba 2003-11-23 devnull e->flags |= VtEntryLocal;
586 056fe1ba 2003-11-23 devnull vtblockput(b);
590 056fe1ba 2003-11-23 devnull vtentrypack(e, p->data, r->offset % r->epb);
591 056fe1ba 2003-11-23 devnull vtblockput(b);
593 056fe1ba 2003-11-23 devnull if(DEPTH(e->type) == depth)
594 056fe1ba 2003-11-23 devnull return 0;
595 056fe1ba 2003-11-23 devnull return -1;
598 056fe1ba 2003-11-23 devnull static int
599 056fe1ba 2003-11-23 devnull shrinkdepth(VtFile *r, VtBlock *p, VtEntry *e, int depth)
601 056fe1ba 2003-11-23 devnull VtBlock *b, *nb, *ob, *rb;
602 056fe1ba 2003-11-23 devnull VtEntry oe;
604 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
605 056fe1ba 2003-11-23 devnull assert(depth <= VtPointerDepth);
607 75d04888 2009-05-25 rsc rb = vtcacheglobal(r->c, e->score, e->type, r->psize);
608 056fe1ba 2003-11-23 devnull if(rb == nil)
612 056fe1ba 2003-11-23 devnull * Walk down to the new root block.
613 056fe1ba 2003-11-23 devnull * We may stop early, but something is better than nothing.
615 056fe1ba 2003-11-23 devnull oe = *e;
617 056fe1ba 2003-11-23 devnull ob = nil;
619 056fe1ba 2003-11-23 devnull for(; DEPTH(e->type) > depth; e->type--){
620 75d04888 2009-05-25 rsc nb = vtcacheglobal(r->c, b->data, e->type-1, r->psize);
621 056fe1ba 2003-11-23 devnull if(nb == nil)
623 056fe1ba 2003-11-23 devnull if(ob!=nil && ob!=rb)
624 056fe1ba 2003-11-23 devnull vtblockput(ob);
629 056fe1ba 2003-11-23 devnull if(b == rb){
630 056fe1ba 2003-11-23 devnull vtblockput(rb);
631 056fe1ba 2003-11-23 devnull return 0;
635 056fe1ba 2003-11-23 devnull * Right now, e points at the root block rb, b is the new root block,
636 056fe1ba 2003-11-23 devnull * and ob points at b. To update:
638 056fe1ba 2003-11-23 devnull * (i) change e to point at b
639 056fe1ba 2003-11-23 devnull * (ii) zero the pointer ob -> b
640 056fe1ba 2003-11-23 devnull * (iii) free the root block
642 056fe1ba 2003-11-23 devnull * p (the block containing e) must be written before
643 056fe1ba 2003-11-23 devnull * anything else.
646 056fe1ba 2003-11-23 devnull /* (i) */
647 056fe1ba 2003-11-23 devnull memmove(e->score, b->score, VtScoreSize);
648 056fe1ba 2003-11-23 devnull vtentrypack(e, p->data, r->offset % r->epb);
650 056fe1ba 2003-11-23 devnull /* (ii) */
651 056fe1ba 2003-11-23 devnull memmove(ob->data, vtzeroscore, VtScoreSize);
653 056fe1ba 2003-11-23 devnull /* (iii) */
654 056fe1ba 2003-11-23 devnull vtblockput(rb);
655 056fe1ba 2003-11-23 devnull if(ob!=nil && ob!=rb)
656 056fe1ba 2003-11-23 devnull vtblockput(ob);
657 056fe1ba 2003-11-23 devnull vtblockput(b);
659 056fe1ba 2003-11-23 devnull if(DEPTH(e->type) == depth)
660 056fe1ba 2003-11-23 devnull return 0;
661 056fe1ba 2003-11-23 devnull return -1;
664 056fe1ba 2003-11-23 devnull static int
665 056fe1ba 2003-11-23 devnull mkindices(VtEntry *e, u32int bn, int *index)
667 056fe1ba 2003-11-23 devnull int i, np;
669 59a96820 2004-06-17 devnull memset(index, 0, (VtPointerDepth+1)*sizeof(int));
671 056fe1ba 2003-11-23 devnull np = e->psize/VtScoreSize;
672 056fe1ba 2003-11-23 devnull for(i=0; bn > 0; i++){
673 056fe1ba 2003-11-23 devnull if(i >= VtPointerDepth){
674 d23a617a 2004-03-15 devnull werrstr("bad address 0x%lux", (ulong)bn);
675 056fe1ba 2003-11-23 devnull return -1;
677 056fe1ba 2003-11-23 devnull index[i] = bn % np;
678 056fe1ba 2003-11-23 devnull bn /= np;
680 056fe1ba 2003-11-23 devnull return i;
683 056fe1ba 2003-11-23 devnull VtBlock *
684 056fe1ba 2003-11-23 devnull vtfileblock(VtFile *r, u32int bn, int mode)
686 056fe1ba 2003-11-23 devnull VtBlock *b, *bb;
687 056fe1ba 2003-11-23 devnull int index[VtPointerDepth+1];
688 056fe1ba 2003-11-23 devnull VtEntry e;
692 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
693 056fe1ba 2003-11-23 devnull assert(bn != NilBlock);
695 056fe1ba 2003-11-23 devnull b = fileload(r, &e);
696 056fe1ba 2003-11-23 devnull if(b == nil)
697 056fe1ba 2003-11-23 devnull return nil;
699 056fe1ba 2003-11-23 devnull i = mkindices(&e, bn, index);
700 056fe1ba 2003-11-23 devnull if(i < 0)
701 6fc7da3c 2006-10-19 devnull goto Err;
702 056fe1ba 2003-11-23 devnull if(i > DEPTH(e.type)){
703 056fe1ba 2003-11-23 devnull if(mode == VtOREAD){
704 d23a617a 2004-03-15 devnull werrstr("bad address 0x%lux", (ulong)bn);
705 056fe1ba 2003-11-23 devnull goto Err;
707 056fe1ba 2003-11-23 devnull index[i] = 0;
708 056fe1ba 2003-11-23 devnull if(growdepth(r, b, &e, i) < 0)
709 056fe1ba 2003-11-23 devnull goto Err;
712 056fe1ba 2003-11-23 devnull assert(b->type == VtDirType);
714 056fe1ba 2003-11-23 devnull index[DEPTH(e.type)] = r->offset % r->epb;
716 056fe1ba 2003-11-23 devnull /* mode for intermediate block */
717 056fe1ba 2003-11-23 devnull m = mode;
718 056fe1ba 2003-11-23 devnull if(m == VtOWRITE)
719 056fe1ba 2003-11-23 devnull m = VtORDWR;
721 056fe1ba 2003-11-23 devnull for(i=DEPTH(e.type); i>=0; i--){
722 75d04888 2009-05-25 rsc bb = blockwalk(r, b, index[i], r->c, i==0 ? mode : m, &e);
723 056fe1ba 2003-11-23 devnull if(bb == nil)
724 056fe1ba 2003-11-23 devnull goto Err;
725 056fe1ba 2003-11-23 devnull vtblockput(b);
728 6fc7da3c 2006-10-19 devnull b->pc = getcallerpc(&r);
729 056fe1ba 2003-11-23 devnull return b;
731 056fe1ba 2003-11-23 devnull vtblockput(b);
732 056fe1ba 2003-11-23 devnull return nil;
736 d23a617a 2004-03-15 devnull vtfileblockscore(VtFile *r, u32int bn, uchar score[VtScoreSize])
738 056fe1ba 2003-11-23 devnull VtBlock *b, *bb;
739 056fe1ba 2003-11-23 devnull int index[VtPointerDepth+1];
740 056fe1ba 2003-11-23 devnull VtEntry e;
743 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
744 056fe1ba 2003-11-23 devnull assert(bn != NilBlock);
746 056fe1ba 2003-11-23 devnull b = fileload(r, &e);
747 056fe1ba 2003-11-23 devnull if(b == nil)
748 056fe1ba 2003-11-23 devnull return -1;
750 e9b70a5f 2008-06-15 rsc if(DEPTH(e.type) == 0){
751 e9b70a5f 2008-06-15 rsc memmove(score, e.score, VtScoreSize);
752 e9b70a5f 2008-06-15 rsc vtblockput(b);
756 056fe1ba 2003-11-23 devnull i = mkindices(&e, bn, index);
757 056fe1ba 2003-11-23 devnull if(i < 0){
758 056fe1ba 2003-11-23 devnull vtblockput(b);
759 056fe1ba 2003-11-23 devnull return -1;
761 056fe1ba 2003-11-23 devnull if(i > DEPTH(e.type)){
762 056fe1ba 2003-11-23 devnull memmove(score, vtzeroscore, VtScoreSize);
763 056fe1ba 2003-11-23 devnull vtblockput(b);
764 056fe1ba 2003-11-23 devnull return 0;
767 056fe1ba 2003-11-23 devnull index[DEPTH(e.type)] = r->offset % r->epb;
769 056fe1ba 2003-11-23 devnull for(i=DEPTH(e.type); i>=1; i--){
770 75d04888 2009-05-25 rsc bb = blockwalk(r, b, index[i], r->c, VtOREAD, &e);
771 056fe1ba 2003-11-23 devnull if(bb == nil)
772 056fe1ba 2003-11-23 devnull goto Err;
773 056fe1ba 2003-11-23 devnull vtblockput(b);
775 056fe1ba 2003-11-23 devnull if(memcmp(b->score, vtzeroscore, VtScoreSize) == 0)
779 056fe1ba 2003-11-23 devnull memmove(score, b->data+index[0]*VtScoreSize, VtScoreSize);
780 056fe1ba 2003-11-23 devnull vtblockput(b);
781 056fe1ba 2003-11-23 devnull return 0;
784 056fe1ba 2003-11-23 devnull vtblockput(b);
785 056fe1ba 2003-11-23 devnull return -1;
789 056fe1ba 2003-11-23 devnull vtfileincref(VtFile *r)
791 056fe1ba 2003-11-23 devnull qlock(&r->lk);
792 056fe1ba 2003-11-23 devnull r->ref++;
793 056fe1ba 2003-11-23 devnull qunlock(&r->lk);
797 056fe1ba 2003-11-23 devnull vtfileclose(VtFile *r)
799 056fe1ba 2003-11-23 devnull if(r == nil)
801 056fe1ba 2003-11-23 devnull qlock(&r->lk);
802 056fe1ba 2003-11-23 devnull r->ref--;
803 056fe1ba 2003-11-23 devnull if(r->ref){
804 056fe1ba 2003-11-23 devnull qunlock(&r->lk);
807 056fe1ba 2003-11-23 devnull assert(r->ref == 0);
808 056fe1ba 2003-11-23 devnull qunlock(&r->lk);
809 056fe1ba 2003-11-23 devnull if(r->parent)
810 056fe1ba 2003-11-23 devnull vtfileclose(r->parent);
811 056fe1ba 2003-11-23 devnull memset(r, ~0, sizeof(*r));
812 056fe1ba 2003-11-23 devnull vtfree(r);
816 056fe1ba 2003-11-23 devnull * Retrieve the block containing the entry for r.
817 056fe1ba 2003-11-23 devnull * If a snapshot has happened, we might need
818 056fe1ba 2003-11-23 devnull * to get a new copy of the block. We avoid this
819 056fe1ba 2003-11-23 devnull * in the common case by caching the score for
820 056fe1ba 2003-11-23 devnull * the block and the last epoch in which it was valid.
822 056fe1ba 2003-11-23 devnull * We use r->mode to tell the difference between active
823 056fe1ba 2003-11-23 devnull * file system VtFiles (VtORDWR) and VtFiles for the
824 056fe1ba 2003-11-23 devnull * snapshot file system (VtOREAD).
826 056fe1ba 2003-11-23 devnull static VtBlock*
827 056fe1ba 2003-11-23 devnull fileloadblock(VtFile *r, int mode)
829 056fe1ba 2003-11-23 devnull char e[ERRMAX];
830 056fe1ba 2003-11-23 devnull u32int addr;
831 056fe1ba 2003-11-23 devnull VtBlock *b;
833 056fe1ba 2003-11-23 devnull switch(r->mode){
834 056fe1ba 2003-11-23 devnull default:
835 056fe1ba 2003-11-23 devnull assert(0);
836 056fe1ba 2003-11-23 devnull case VtORDWR:
837 056fe1ba 2003-11-23 devnull assert(r->mode == VtORDWR);
838 056fe1ba 2003-11-23 devnull if(r->local == 1){
839 75d04888 2009-05-25 rsc b = vtcacheglobal(r->c, r->score, VtDirType, r->bsize);
840 056fe1ba 2003-11-23 devnull if(b == nil)
841 056fe1ba 2003-11-23 devnull return nil;
842 6fc7da3c 2006-10-19 devnull b->pc = getcallerpc(&r);
843 056fe1ba 2003-11-23 devnull return b;
845 056fe1ba 2003-11-23 devnull assert(r->parent != nil);
846 056fe1ba 2003-11-23 devnull if(vtfilelock(r->parent, VtORDWR) < 0)
847 056fe1ba 2003-11-23 devnull return nil;
848 056fe1ba 2003-11-23 devnull b = vtfileblock(r->parent, r->offset/r->epb, VtORDWR);
849 056fe1ba 2003-11-23 devnull vtfileunlock(r->parent);
850 056fe1ba 2003-11-23 devnull if(b == nil)
851 056fe1ba 2003-11-23 devnull return nil;
852 056fe1ba 2003-11-23 devnull memmove(r->score, b->score, VtScoreSize);
853 056fe1ba 2003-11-23 devnull r->local = 1;
854 056fe1ba 2003-11-23 devnull return b;
856 056fe1ba 2003-11-23 devnull case VtOREAD:
857 056fe1ba 2003-11-23 devnull if(mode == VtORDWR){
858 056fe1ba 2003-11-23 devnull werrstr("read/write lock of read-only file");
859 056fe1ba 2003-11-23 devnull return nil;
861 056fe1ba 2003-11-23 devnull addr = vtglobaltolocal(r->score);
862 056fe1ba 2003-11-23 devnull if(addr == NilBlock)
863 75d04888 2009-05-25 rsc return vtcacheglobal(r->c, r->score, VtDirType, r->bsize);
865 056fe1ba 2003-11-23 devnull b = vtcachelocal(r->c, addr, VtDirType);
867 056fe1ba 2003-11-23 devnull return b;
870 056fe1ba 2003-11-23 devnull * If it failed because the epochs don't match, the block has been
871 056fe1ba 2003-11-23 devnull * archived and reclaimed. Rewalk from the parent and get the
872 056fe1ba 2003-11-23 devnull * new pointer. This can't happen in the VtORDWR case
873 056fe1ba 2003-11-23 devnull * above because blocks in the current epoch don't get
874 056fe1ba 2003-11-23 devnull * reclaimed. The fact that we're VtOREAD means we're
875 056fe1ba 2003-11-23 devnull * a snapshot. (Or else the file system is read-only, but then
876 056fe1ba 2003-11-23 devnull * the archiver isn't going around deleting blocks.)
878 056fe1ba 2003-11-23 devnull rerrstr(e, sizeof e);
879 056fe1ba 2003-11-23 devnull if(strcmp(e, ELabelMismatch) == 0){
880 056fe1ba 2003-11-23 devnull if(vtfilelock(r->parent, VtOREAD) < 0)
881 056fe1ba 2003-11-23 devnull return nil;
882 056fe1ba 2003-11-23 devnull b = vtfileblock(r->parent, r->offset/r->epb, VtOREAD);
883 056fe1ba 2003-11-23 devnull vtfileunlock(r->parent);
885 056fe1ba 2003-11-23 devnull fprint(2, "vtfilealloc: lost %V found %V\n",
886 056fe1ba 2003-11-23 devnull r->score, b->score);
887 056fe1ba 2003-11-23 devnull memmove(r->score, b->score, VtScoreSize);
888 056fe1ba 2003-11-23 devnull return b;
891 056fe1ba 2003-11-23 devnull return nil;
896 056fe1ba 2003-11-23 devnull vtfilelock(VtFile *r, int mode)
898 056fe1ba 2003-11-23 devnull VtBlock *b;
900 056fe1ba 2003-11-23 devnull if(mode == -1)
901 056fe1ba 2003-11-23 devnull mode = r->mode;
903 056fe1ba 2003-11-23 devnull b = fileloadblock(r, mode);
904 056fe1ba 2003-11-23 devnull if(b == nil)
905 056fe1ba 2003-11-23 devnull return -1;
907 056fe1ba 2003-11-23 devnull * The fact that we are holding b serves as the
908 056fe1ba 2003-11-23 devnull * lock entitling us to write to r->b.
910 056fe1ba 2003-11-23 devnull assert(r->b == nil);
911 056fe1ba 2003-11-23 devnull r->b = b;
912 6fc7da3c 2006-10-19 devnull b->pc = getcallerpc(&r);
913 056fe1ba 2003-11-23 devnull return 0;
917 056fe1ba 2003-11-23 devnull * Lock two (usually sibling) VtFiles. This needs special care
918 056fe1ba 2003-11-23 devnull * because the Entries for both vtFiles might be in the same block.
919 056fe1ba 2003-11-23 devnull * We also try to lock blocks in left-to-right order within the tree.
922 056fe1ba 2003-11-23 devnull vtfilelock2(VtFile *r, VtFile *rr, int mode)
924 056fe1ba 2003-11-23 devnull VtBlock *b, *bb;
926 056fe1ba 2003-11-23 devnull if(rr == nil)
927 056fe1ba 2003-11-23 devnull return vtfilelock(r, mode);
929 056fe1ba 2003-11-23 devnull if(mode == -1)
930 056fe1ba 2003-11-23 devnull mode = r->mode;
932 056fe1ba 2003-11-23 devnull if(r->parent==rr->parent && r->offset/r->epb == rr->offset/rr->epb){
933 056fe1ba 2003-11-23 devnull b = fileloadblock(r, mode);
934 056fe1ba 2003-11-23 devnull if(b == nil)
935 056fe1ba 2003-11-23 devnull return -1;
936 056fe1ba 2003-11-23 devnull vtblockduplock(b);
938 056fe1ba 2003-11-23 devnull }else if(r->parent==rr->parent || r->offset > rr->offset){
939 056fe1ba 2003-11-23 devnull bb = fileloadblock(rr, mode);
940 056fe1ba 2003-11-23 devnull b = fileloadblock(r, mode);
942 056fe1ba 2003-11-23 devnull b = fileloadblock(r, mode);
943 056fe1ba 2003-11-23 devnull bb = fileloadblock(rr, mode);
945 056fe1ba 2003-11-23 devnull if(b == nil || bb == nil){
947 056fe1ba 2003-11-23 devnull vtblockput(b);
949 056fe1ba 2003-11-23 devnull vtblockput(bb);
950 056fe1ba 2003-11-23 devnull return -1;
954 056fe1ba 2003-11-23 devnull * The fact that we are holding b and bb serves
955 056fe1ba 2003-11-23 devnull * as the lock entitling us to write to r->b and rr->b.
957 056fe1ba 2003-11-23 devnull r->b = b;
958 056fe1ba 2003-11-23 devnull rr->b = bb;
959 6fc7da3c 2006-10-19 devnull b->pc = getcallerpc(&r);
960 6fc7da3c 2006-10-19 devnull bb->pc = getcallerpc(&r);
961 056fe1ba 2003-11-23 devnull return 0;
965 056fe1ba 2003-11-23 devnull vtfileunlock(VtFile *r)
967 056fe1ba 2003-11-23 devnull VtBlock *b;
969 056fe1ba 2003-11-23 devnull if(r->b == nil){
970 056fe1ba 2003-11-23 devnull fprint(2, "vtfileunlock: already unlocked\n");
971 056fe1ba 2003-11-23 devnull abort();
973 056fe1ba 2003-11-23 devnull b = r->b;
974 056fe1ba 2003-11-23 devnull r->b = nil;
975 056fe1ba 2003-11-23 devnull vtblockput(b);
978 056fe1ba 2003-11-23 devnull static VtBlock*
979 056fe1ba 2003-11-23 devnull fileload(VtFile *r, VtEntry *e)
981 056fe1ba 2003-11-23 devnull VtBlock *b;
983 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
984 056fe1ba 2003-11-23 devnull b = r->b;
985 056fe1ba 2003-11-23 devnull if(vtentryunpack(e, b->data, r->offset % r->epb) < 0)
986 056fe1ba 2003-11-23 devnull return nil;
987 056fe1ba 2003-11-23 devnull vtblockduplock(b);
988 056fe1ba 2003-11-23 devnull return b;
991 056fe1ba 2003-11-23 devnull static int
992 056fe1ba 2003-11-23 devnull sizetodepth(uvlong s, int psize, int dsize)
997 056fe1ba 2003-11-23 devnull /* determine pointer depth */
998 056fe1ba 2003-11-23 devnull np = psize/VtScoreSize;
999 056fe1ba 2003-11-23 devnull s = (s + dsize - 1)/dsize;
1000 056fe1ba 2003-11-23 devnull for(d = 0; s > 1; d++)
1001 056fe1ba 2003-11-23 devnull s = (s + np - 1)/np;
1002 056fe1ba 2003-11-23 devnull return d;
1006 056fe1ba 2003-11-23 devnull vtfileread(VtFile *f, void *data, long count, vlong offset)
1008 056fe1ba 2003-11-23 devnull int frag;
1009 056fe1ba 2003-11-23 devnull VtBlock *b;
1010 056fe1ba 2003-11-23 devnull VtEntry e;
1012 056fe1ba 2003-11-23 devnull assert(ISLOCKED(f));
1014 056fe1ba 2003-11-23 devnull vtfilegetentry(f, &e);
1015 056fe1ba 2003-11-23 devnull if(count == 0)
1016 056fe1ba 2003-11-23 devnull return 0;
1017 056fe1ba 2003-11-23 devnull if(count < 0 || offset < 0){
1018 056fe1ba 2003-11-23 devnull werrstr("vtfileread: bad offset or count");
1019 056fe1ba 2003-11-23 devnull return -1;
1021 056fe1ba 2003-11-23 devnull if(offset >= e.size)
1022 056fe1ba 2003-11-23 devnull return 0;
1024 056fe1ba 2003-11-23 devnull if(offset+count > e.size)
1025 056fe1ba 2003-11-23 devnull count = e.size - offset;
1027 056fe1ba 2003-11-23 devnull frag = offset % e.dsize;
1028 056fe1ba 2003-11-23 devnull if(frag+count > e.dsize)
1029 056fe1ba 2003-11-23 devnull count = e.dsize - frag;
1031 056fe1ba 2003-11-23 devnull b = vtfileblock(f, offset/e.dsize, VtOREAD);
1032 056fe1ba 2003-11-23 devnull if(b == nil)
1033 056fe1ba 2003-11-23 devnull return -1;
1035 056fe1ba 2003-11-23 devnull memmove(data, b->data+frag, count);
1036 056fe1ba 2003-11-23 devnull vtblockput(b);
1037 056fe1ba 2003-11-23 devnull return count;
1040 056fe1ba 2003-11-23 devnull static long
1041 056fe1ba 2003-11-23 devnull filewrite1(VtFile *f, void *data, long count, vlong offset)
1043 056fe1ba 2003-11-23 devnull int frag, m;
1044 056fe1ba 2003-11-23 devnull VtBlock *b;
1045 056fe1ba 2003-11-23 devnull VtEntry e;
1047 056fe1ba 2003-11-23 devnull vtfilegetentry(f, &e);
1048 056fe1ba 2003-11-23 devnull if(count < 0 || offset < 0){
1049 6ce75e8d 2007-04-21 devnull werrstr("vtfilewrite: bad offset or count");
1050 056fe1ba 2003-11-23 devnull return -1;
1053 056fe1ba 2003-11-23 devnull frag = offset % e.dsize;
1054 056fe1ba 2003-11-23 devnull if(frag+count > e.dsize)
1055 056fe1ba 2003-11-23 devnull count = e.dsize - frag;
1057 056fe1ba 2003-11-23 devnull m = VtORDWR;
1058 056fe1ba 2003-11-23 devnull if(frag == 0 && count == e.dsize)
1059 056fe1ba 2003-11-23 devnull m = VtOWRITE;
1061 056fe1ba 2003-11-23 devnull b = vtfileblock(f, offset/e.dsize, m);
1062 056fe1ba 2003-11-23 devnull if(b == nil)
1063 056fe1ba 2003-11-23 devnull return -1;
1065 056fe1ba 2003-11-23 devnull memmove(b->data+frag, data, count);
1066 e9b70a5f 2008-06-15 rsc if(m == VtOWRITE && frag+count < e.dsize)
1067 e9b70a5f 2008-06-15 rsc memset(b->data+frag+count, 0, e.dsize-frag-count);
1069 056fe1ba 2003-11-23 devnull if(offset+count > e.size){
1070 056fe1ba 2003-11-23 devnull vtfilegetentry(f, &e);
1071 056fe1ba 2003-11-23 devnull e.size = offset+count;
1072 056fe1ba 2003-11-23 devnull vtfilesetentry(f, &e);
1075 056fe1ba 2003-11-23 devnull vtblockput(b);
1076 056fe1ba 2003-11-23 devnull return count;
1080 056fe1ba 2003-11-23 devnull vtfilewrite(VtFile *f, void *data, long count, vlong offset)
1082 056fe1ba 2003-11-23 devnull long tot, m;
1084 056fe1ba 2003-11-23 devnull assert(ISLOCKED(f));
1086 056fe1ba 2003-11-23 devnull tot = 0;
1088 056fe1ba 2003-11-23 devnull while(tot < count){
1089 056fe1ba 2003-11-23 devnull m = filewrite1(f, (char*)data+tot, count-tot, offset+tot);
1090 056fe1ba 2003-11-23 devnull if(m <= 0)
1092 056fe1ba 2003-11-23 devnull tot += m;
1094 056fe1ba 2003-11-23 devnull if(tot==0)
1095 056fe1ba 2003-11-23 devnull return m;
1096 056fe1ba 2003-11-23 devnull return tot;
1099 056fe1ba 2003-11-23 devnull static int
1100 056fe1ba 2003-11-23 devnull flushblock(VtCache *c, VtBlock *bb, uchar score[VtScoreSize], int ppb, int epb,
1101 056fe1ba 2003-11-23 devnull int type)
1103 056fe1ba 2003-11-23 devnull u32int addr;
1104 056fe1ba 2003-11-23 devnull VtBlock *b;
1105 056fe1ba 2003-11-23 devnull VtEntry e;
1108 056fe1ba 2003-11-23 devnull addr = vtglobaltolocal(score);
1109 056fe1ba 2003-11-23 devnull if(addr == NilBlock)
1110 056fe1ba 2003-11-23 devnull return 0;
1112 056fe1ba 2003-11-23 devnull if(bb){
1113 056fe1ba 2003-11-23 devnull b = bb;
1114 056fe1ba 2003-11-23 devnull if(memcmp(b->score, score, VtScoreSize) != 0)
1115 056fe1ba 2003-11-23 devnull abort();
1117 056fe1ba 2003-11-23 devnull if((b = vtcachelocal(c, addr, type)) == nil)
1118 056fe1ba 2003-11-23 devnull return -1;
1120 056fe1ba 2003-11-23 devnull switch(type){
1121 056fe1ba 2003-11-23 devnull case VtDataType:
1124 056fe1ba 2003-11-23 devnull case VtDirType:
1125 056fe1ba 2003-11-23 devnull for(i=0; i<epb; i++){
1126 056fe1ba 2003-11-23 devnull if(vtentryunpack(&e, b->data, i) < 0)
1127 056fe1ba 2003-11-23 devnull goto Err;
1128 e9b70a5f 2008-06-15 rsc if(!(e.flags&VtEntryActive))
1130 056fe1ba 2003-11-23 devnull if(flushblock(c, nil, e.score, e.psize/VtScoreSize, e.dsize/VtEntrySize,
1131 056fe1ba 2003-11-23 devnull e.type) < 0)
1132 056fe1ba 2003-11-23 devnull goto Err;
1133 e9b70a5f 2008-06-15 rsc vtentrypack(&e, b->data, i);
1137 056fe1ba 2003-11-23 devnull default: /* VtPointerTypeX */
1138 056fe1ba 2003-11-23 devnull for(i=0; i<ppb; i++){
1139 056fe1ba 2003-11-23 devnull if(flushblock(c, nil, b->data+VtScoreSize*i, ppb, epb, type-1) < 0)
1140 056fe1ba 2003-11-23 devnull goto Err;
1145 056fe1ba 2003-11-23 devnull if(vtblockwrite(b) < 0)
1146 056fe1ba 2003-11-23 devnull goto Err;
1147 056fe1ba 2003-11-23 devnull memmove(score, b->score, VtScoreSize);
1148 056fe1ba 2003-11-23 devnull if(b != bb)
1149 056fe1ba 2003-11-23 devnull vtblockput(b);
1150 056fe1ba 2003-11-23 devnull return 0;
1153 056fe1ba 2003-11-23 devnull if(b != bb)
1154 056fe1ba 2003-11-23 devnull vtblockput(b);
1155 056fe1ba 2003-11-23 devnull return -1;
1159 056fe1ba 2003-11-23 devnull vtfileflush(VtFile *f)
1161 056fe1ba 2003-11-23 devnull int ret;
1162 056fe1ba 2003-11-23 devnull VtBlock *b;
1163 056fe1ba 2003-11-23 devnull VtEntry e;
1165 056fe1ba 2003-11-23 devnull assert(ISLOCKED(f));
1166 056fe1ba 2003-11-23 devnull b = fileload(f, &e);
1167 056fe1ba 2003-11-23 devnull if(!(e.flags&VtEntryLocal)){
1168 056fe1ba 2003-11-23 devnull vtblockput(b);
1169 056fe1ba 2003-11-23 devnull return 0;
1172 056fe1ba 2003-11-23 devnull ret = flushblock(f->c, nil, e.score, e.psize/VtScoreSize, e.dsize/VtEntrySize,
1173 056fe1ba 2003-11-23 devnull e.type);
1174 7cb74894 2004-06-17 devnull if(ret < 0){
1175 056fe1ba 2003-11-23 devnull vtblockput(b);
1176 056fe1ba 2003-11-23 devnull return -1;
1179 056fe1ba 2003-11-23 devnull vtentrypack(&e, b->data, f->offset % f->epb);
1180 056fe1ba 2003-11-23 devnull vtblockput(b);
1181 056fe1ba 2003-11-23 devnull return 0;
1185 056fe1ba 2003-11-23 devnull vtfileflushbefore(VtFile *r, u64int offset)
1187 056fe1ba 2003-11-23 devnull VtBlock *b, *bb;
1188 056fe1ba 2003-11-23 devnull VtEntry e;
1189 59a96820 2004-06-17 devnull int i, base, depth, ppb, epb, doflush;
1190 59a96820 2004-06-17 devnull int index[VtPointerDepth+1], j, ret;
1191 056fe1ba 2003-11-23 devnull VtBlock *bi[VtPointerDepth+2];
1192 056fe1ba 2003-11-23 devnull uchar *score;
1194 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
1195 056fe1ba 2003-11-23 devnull if(offset == 0)
1196 056fe1ba 2003-11-23 devnull return 0;
1198 056fe1ba 2003-11-23 devnull b = fileload(r, &e);
1199 056fe1ba 2003-11-23 devnull if(b == nil)
1200 056fe1ba 2003-11-23 devnull return -1;
1203 59a96820 2004-06-17 devnull * compute path through tree for the last written byte and the next one.
1205 056fe1ba 2003-11-23 devnull ret = -1;
1206 056fe1ba 2003-11-23 devnull memset(bi, 0, sizeof bi);
1207 056fe1ba 2003-11-23 devnull depth = DEPTH(e.type);
1208 056fe1ba 2003-11-23 devnull bi[depth+1] = b;
1209 056fe1ba 2003-11-23 devnull i = mkindices(&e, (offset-1)/e.dsize, index);
1210 056fe1ba 2003-11-23 devnull if(i < 0)
1211 056fe1ba 2003-11-23 devnull goto Err;
1212 056fe1ba 2003-11-23 devnull if(i > depth)
1213 056fe1ba 2003-11-23 devnull goto Err;
1214 056fe1ba 2003-11-23 devnull ppb = e.psize / VtScoreSize;
1215 056fe1ba 2003-11-23 devnull epb = e.dsize / VtEntrySize;
1218 59a96820 2004-06-17 devnull * load the blocks along the last written byte
1220 056fe1ba 2003-11-23 devnull index[depth] = r->offset % r->epb;
1221 056fe1ba 2003-11-23 devnull for(i=depth; i>=0; i--){
1222 75d04888 2009-05-25 rsc bb = blockwalk(r, b, index[i], r->c, VtORDWR, &e);
1223 056fe1ba 2003-11-23 devnull if(bb == nil)
1224 056fe1ba 2003-11-23 devnull goto Err;
1225 056fe1ba 2003-11-23 devnull bi[i] = bb;
1226 056fe1ba 2003-11-23 devnull b = bb;
1228 056fe1ba 2003-11-23 devnull ret = 0;
1231 59a96820 2004-06-17 devnull * walk up the path from leaf to root, flushing anything that
1232 59a96820 2004-06-17 devnull * has been finished.
1234 056fe1ba 2003-11-23 devnull base = e.type&~VtTypeDepthMask;
1235 005ee04b 2004-06-17 devnull for(i=0; i<=depth; i++){
1236 59a96820 2004-06-17 devnull doflush = 0;
1237 056fe1ba 2003-11-23 devnull if(i == 0){
1238 59a96820 2004-06-17 devnull /* leaf: data or dir block */
1239 59a96820 2004-06-17 devnull if(offset%e.dsize == 0)
1240 59a96820 2004-06-17 devnull doflush = 1;
1243 59a96820 2004-06-17 devnull * interior node: pointer blocks.
1244 59a96820 2004-06-17 devnull * specifically, b = bi[i] is a block whose index[i-1]'th entry
1245 59a96820 2004-06-17 devnull * points at bi[i-1].
1247 056fe1ba 2003-11-23 devnull b = bi[i];
1250 59a96820 2004-06-17 devnull * the index entries up to but not including index[i-1] point at
1251 59a96820 2004-06-17 devnull * finished blocks, so flush them for sure.
1253 056fe1ba 2003-11-23 devnull for(j=0; j<index[i-1]; j++)
1254 056fe1ba 2003-11-23 devnull if(flushblock(r->c, nil, b->data+j*VtScoreSize, ppb, epb, base+i-1) < 0)
1255 056fe1ba 2003-11-23 devnull goto Err;
1258 59a96820 2004-06-17 devnull * if index[i-1] is the last entry in the block and is global
1259 59a96820 2004-06-17 devnull * (i.e. the kid is flushed), then we can flush this block.
1261 59a96820 2004-06-17 devnull if(j==ppb-1 && vtglobaltolocal(b->data+j*VtScoreSize)==NilBlock)
1262 59a96820 2004-06-17 devnull doflush = 1;
1264 59a96820 2004-06-17 devnull if(doflush){
1265 056fe1ba 2003-11-23 devnull if(i == depth)
1266 056fe1ba 2003-11-23 devnull score = e.score;
1268 056fe1ba 2003-11-23 devnull score = bi[i+1]->data+index[i]*VtScoreSize;
1269 056fe1ba 2003-11-23 devnull if(flushblock(r->c, bi[i], score, ppb, epb, base+i) < 0)
1270 056fe1ba 2003-11-23 devnull goto Err;
1275 056fe1ba 2003-11-23 devnull /* top: entry. do this always so that the score is up-to-date */
1276 056fe1ba 2003-11-23 devnull vtentrypack(&e, bi[depth+1]->data, index[depth]);
1277 056fe1ba 2003-11-23 devnull for(i=0; i<nelem(bi); i++)
1278 056fe1ba 2003-11-23 devnull if(bi[i])
1279 056fe1ba 2003-11-23 devnull vtblockput(bi[i]);
1280 056fe1ba 2003-11-23 devnull return ret;
