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 u32int size;
40 056fe1ba 2003-11-23 devnull VtEntry e;
41 056fe1ba 2003-11-23 devnull VtFile *r;
43 056fe1ba 2003-11-23 devnull assert(p==nil || ISLOCKED(p));
45 056fe1ba 2003-11-23 devnull if(p == nil){
46 056fe1ba 2003-11-23 devnull assert(offset == 0);
49 056fe1ba 2003-11-23 devnull epb = p->dsize / VtEntrySize;
51 23fb2edb 2005-07-24 devnull if(b->type != VtDirType){
52 23fb2edb 2005-07-24 devnull werrstr("bad block type %#uo", b->type);
53 23fb2edb 2005-07-24 devnull return nil;
57 056fe1ba 2003-11-23 devnull * a non-active entry is the only thing that
58 056fe1ba 2003-11-23 devnull * can legitimately happen here. all the others
59 056fe1ba 2003-11-23 devnull * get prints.
61 056fe1ba 2003-11-23 devnull if(vtentryunpack(&e, b->data, offset % epb) < 0){
62 23fb2edb 2005-07-24 devnull fprint(2, "vtentryunpack failed: %r (%.*H)\n", VtEntrySize, b->data+VtEntrySize*(offset%epb));
63 23fb2edb 2005-07-24 devnull return nil;
65 056fe1ba 2003-11-23 devnull if(!(e.flags & VtEntryActive)){
66 23fb2edb 2005-07-24 devnull werrstr("entry not active");
67 23fb2edb 2005-07-24 devnull return nil;
70 056fe1ba 2003-11-23 devnull if(DEPTH(e.type) < sizetodepth(e.size, e.psize, e.dsize)){
71 056fe1ba 2003-11-23 devnull fprint(2, "depth %ud size %llud psize %ud dsize %ud\n",
72 056fe1ba 2003-11-23 devnull DEPTH(e.type), e.size, e.psize, e.dsize);
73 23fb2edb 2005-07-24 devnull werrstr("bad depth");
74 23fb2edb 2005-07-24 devnull return nil;
77 056fe1ba 2003-11-23 devnull size = vtcacheblocksize(c);
78 056fe1ba 2003-11-23 devnull if(e.dsize > size || e.psize > size){
79 23fb2edb 2005-07-24 devnull werrstr("block sizes %ud, %ud bigger than cache block size %ud",
80 23fb2edb 2005-07-24 devnull e.psize, e.dsize, size);
81 23fb2edb 2005-07-24 devnull return nil;
84 056fe1ba 2003-11-23 devnull r = vtmallocz(sizeof(VtFile));
85 056fe1ba 2003-11-23 devnull r->c = c;
86 056fe1ba 2003-11-23 devnull r->mode = mode;
87 056fe1ba 2003-11-23 devnull r->dsize = e.dsize;
88 c1e6f642 2005-07-13 devnull r->psize = e.psize;
89 056fe1ba 2003-11-23 devnull r->gen = e.gen;
90 d23a617a 2004-03-15 devnull r->dir = (e.type & VtTypeBaseMask) == VtDirType;
91 056fe1ba 2003-11-23 devnull r->ref = 1;
92 056fe1ba 2003-11-23 devnull r->parent = p;
94 056fe1ba 2003-11-23 devnull qlock(&p->lk);
95 056fe1ba 2003-11-23 devnull assert(mode == VtOREAD || p->mode == VtORDWR);
96 056fe1ba 2003-11-23 devnull p->ref++;
97 056fe1ba 2003-11-23 devnull qunlock(&p->lk);
99 7cb74894 2004-06-17 devnull assert(b->addr != NilBlock);
100 7cb74894 2004-06-17 devnull r->local = 1;
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;
109 056fe1ba 2003-11-23 devnull VtFile *
110 056fe1ba 2003-11-23 devnull vtfileroot(VtCache *c, u32int addr, int mode)
112 056fe1ba 2003-11-23 devnull VtFile *r;
113 056fe1ba 2003-11-23 devnull VtBlock *b;
115 056fe1ba 2003-11-23 devnull b = vtcachelocal(c, addr, VtDirType);
116 056fe1ba 2003-11-23 devnull if(b == nil)
117 056fe1ba 2003-11-23 devnull return nil;
118 056fe1ba 2003-11-23 devnull r = vtfilealloc(c, b, nil, 0, mode);
119 056fe1ba 2003-11-23 devnull vtblockput(b);
120 056fe1ba 2003-11-23 devnull return r;
124 056fe1ba 2003-11-23 devnull vtfileopenroot(VtCache *c, VtEntry *e)
126 056fe1ba 2003-11-23 devnull VtBlock *b;
127 056fe1ba 2003-11-23 devnull VtFile *f;
129 056fe1ba 2003-11-23 devnull b = vtcacheallocblock(c, VtDirType);
130 056fe1ba 2003-11-23 devnull if(b == nil)
131 056fe1ba 2003-11-23 devnull return nil;
133 056fe1ba 2003-11-23 devnull vtentrypack(e, b->data, 0);
134 056fe1ba 2003-11-23 devnull f = vtfilealloc(c, b, nil, 0, VtORDWR);
135 056fe1ba 2003-11-23 devnull vtblockput(b);
136 056fe1ba 2003-11-23 devnull return f;
139 056fe1ba 2003-11-23 devnull VtFile *
140 056fe1ba 2003-11-23 devnull vtfilecreateroot(VtCache *c, int psize, int dsize, int type)
142 056fe1ba 2003-11-23 devnull VtEntry e;
144 056fe1ba 2003-11-23 devnull memset(&e, 0, sizeof e);
145 056fe1ba 2003-11-23 devnull e.flags = VtEntryActive;
146 056fe1ba 2003-11-23 devnull e.psize = psize;
147 056fe1ba 2003-11-23 devnull e.dsize = dsize;
148 d23a617a 2004-03-15 devnull e.type = type;
149 056fe1ba 2003-11-23 devnull memmove(e.score, vtzeroscore, VtScoreSize);
151 056fe1ba 2003-11-23 devnull return vtfileopenroot(c, &e);
154 056fe1ba 2003-11-23 devnull VtFile *
155 056fe1ba 2003-11-23 devnull vtfileopen(VtFile *r, u32int offset, int mode)
157 056fe1ba 2003-11-23 devnull ulong bn;
158 056fe1ba 2003-11-23 devnull VtBlock *b;
160 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
161 056fe1ba 2003-11-23 devnull if(!r->dir){
162 056fe1ba 2003-11-23 devnull werrstr(ENotDir);
163 056fe1ba 2003-11-23 devnull return nil;
166 056fe1ba 2003-11-23 devnull bn = offset/(r->dsize/VtEntrySize);
168 056fe1ba 2003-11-23 devnull b = vtfileblock(r, bn, mode);
169 056fe1ba 2003-11-23 devnull if(b == nil)
170 056fe1ba 2003-11-23 devnull return nil;
171 056fe1ba 2003-11-23 devnull r = vtfilealloc(r->c, b, r, offset, mode);
172 056fe1ba 2003-11-23 devnull vtblockput(b);
173 056fe1ba 2003-11-23 devnull return r;
177 3082404e 2005-07-13 devnull vtfilecreate(VtFile *r, int psize, int dsize, int type)
179 23fb2edb 2005-07-24 devnull return _vtfilecreate(r, -1, psize, dsize, type);
183 23fb2edb 2005-07-24 devnull _vtfilecreate(VtFile *r, int o, int psize, int dsize, int type)
186 056fe1ba 2003-11-23 devnull VtBlock *b;
187 056fe1ba 2003-11-23 devnull u32int bn, size;
188 056fe1ba 2003-11-23 devnull VtEntry e;
189 056fe1ba 2003-11-23 devnull int epb;
190 056fe1ba 2003-11-23 devnull VtFile *rr;
191 23fb2edb 2005-07-24 devnull u32int offset;
193 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
194 c5eb6860 2004-06-16 devnull assert(psize <= VtMaxLumpSize);
195 c5eb6860 2004-06-16 devnull assert(dsize <= VtMaxLumpSize);
196 3082404e 2005-07-13 devnull assert(type == VtDirType || type == VtDataType);
198 056fe1ba 2003-11-23 devnull if(!r->dir){
199 056fe1ba 2003-11-23 devnull werrstr(ENotDir);
200 056fe1ba 2003-11-23 devnull return nil;
203 056fe1ba 2003-11-23 devnull epb = r->dsize/VtEntrySize;
205 056fe1ba 2003-11-23 devnull size = vtfilegetdirsize(r);
207 056fe1ba 2003-11-23 devnull * look at a random block to see if we can find an empty entry
209 23fb2edb 2005-07-24 devnull if(o == -1){
210 23fb2edb 2005-07-24 devnull offset = lnrand(size+1);
211 23fb2edb 2005-07-24 devnull offset -= offset % epb;
213 23fb2edb 2005-07-24 devnull offset = o;
215 056fe1ba 2003-11-23 devnull /* try the given block and then try the last block */
216 056fe1ba 2003-11-23 devnull for(;;){
217 056fe1ba 2003-11-23 devnull bn = offset/epb;
218 056fe1ba 2003-11-23 devnull b = vtfileblock(r, bn, VtORDWR);
219 056fe1ba 2003-11-23 devnull if(b == nil)
220 056fe1ba 2003-11-23 devnull return nil;
221 056fe1ba 2003-11-23 devnull for(i=offset%r->epb; i<epb; i++){
222 056fe1ba 2003-11-23 devnull if(vtentryunpack(&e, b->data, i) < 0)
223 056fe1ba 2003-11-23 devnull continue;
224 056fe1ba 2003-11-23 devnull if((e.flags&VtEntryActive) == 0 && e.gen != ~0)
225 056fe1ba 2003-11-23 devnull goto Found;
227 056fe1ba 2003-11-23 devnull vtblockput(b);
228 056fe1ba 2003-11-23 devnull if(offset == size){
229 056fe1ba 2003-11-23 devnull fprint(2, "vtfilecreate: cannot happen\n");
230 056fe1ba 2003-11-23 devnull werrstr("vtfilecreate: cannot happen");
231 056fe1ba 2003-11-23 devnull return nil;
233 056fe1ba 2003-11-23 devnull offset = size;
237 056fe1ba 2003-11-23 devnull /* found an entry - gen already set */
238 056fe1ba 2003-11-23 devnull e.psize = psize;
239 056fe1ba 2003-11-23 devnull e.dsize = dsize;
240 056fe1ba 2003-11-23 devnull e.flags = VtEntryActive;
241 3082404e 2005-07-13 devnull e.type = type;
242 056fe1ba 2003-11-23 devnull e.size = 0;
243 056fe1ba 2003-11-23 devnull memmove(e.score, vtzeroscore, VtScoreSize);
244 056fe1ba 2003-11-23 devnull vtentrypack(&e, b->data, i);
246 056fe1ba 2003-11-23 devnull offset = bn*epb + i;
247 056fe1ba 2003-11-23 devnull if(offset+1 > size){
248 056fe1ba 2003-11-23 devnull if(vtfilesetdirsize(r, offset+1) < 0){
249 056fe1ba 2003-11-23 devnull vtblockput(b);
250 056fe1ba 2003-11-23 devnull return nil;
254 056fe1ba 2003-11-23 devnull rr = vtfilealloc(r->c, b, r, offset, VtORDWR);
255 056fe1ba 2003-11-23 devnull vtblockput(b);
256 056fe1ba 2003-11-23 devnull return rr;
259 056fe1ba 2003-11-23 devnull static int
260 056fe1ba 2003-11-23 devnull vtfilekill(VtFile *r, int doremove)
262 056fe1ba 2003-11-23 devnull VtEntry e;
263 056fe1ba 2003-11-23 devnull VtBlock *b;
265 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
266 056fe1ba 2003-11-23 devnull b = fileload(r, &e);
267 056fe1ba 2003-11-23 devnull if(b == nil)
268 056fe1ba 2003-11-23 devnull return -1;
270 056fe1ba 2003-11-23 devnull if(doremove==0 && e.size == 0){
271 056fe1ba 2003-11-23 devnull /* already truncated */
272 056fe1ba 2003-11-23 devnull vtblockput(b);
273 056fe1ba 2003-11-23 devnull return 0;
276 056fe1ba 2003-11-23 devnull if(doremove){
277 056fe1ba 2003-11-23 devnull if(e.gen != ~0)
278 056fe1ba 2003-11-23 devnull e.gen++;
279 056fe1ba 2003-11-23 devnull e.dsize = 0;
280 056fe1ba 2003-11-23 devnull e.psize = 0;
281 056fe1ba 2003-11-23 devnull e.flags = 0;
283 056fe1ba 2003-11-23 devnull e.flags &= ~VtEntryLocal;
284 056fe1ba 2003-11-23 devnull e.type = 0;
285 056fe1ba 2003-11-23 devnull e.size = 0;
286 056fe1ba 2003-11-23 devnull memmove(e.score, vtzeroscore, VtScoreSize);
287 056fe1ba 2003-11-23 devnull vtentrypack(&e, b->data, r->offset % r->epb);
288 056fe1ba 2003-11-23 devnull vtblockput(b);
290 056fe1ba 2003-11-23 devnull if(doremove){
291 056fe1ba 2003-11-23 devnull vtfileunlock(r);
292 056fe1ba 2003-11-23 devnull vtfileclose(r);
295 056fe1ba 2003-11-23 devnull return 0;
299 056fe1ba 2003-11-23 devnull vtfileremove(VtFile *r)
301 056fe1ba 2003-11-23 devnull return vtfilekill(r, 1);
305 056fe1ba 2003-11-23 devnull vtfiletruncate(VtFile *r)
307 056fe1ba 2003-11-23 devnull return vtfilekill(r, 0);
311 056fe1ba 2003-11-23 devnull vtfilegetsize(VtFile *r)
313 056fe1ba 2003-11-23 devnull VtEntry e;
314 056fe1ba 2003-11-23 devnull VtBlock *b;
316 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
317 056fe1ba 2003-11-23 devnull b = fileload(r, &e);
318 056fe1ba 2003-11-23 devnull if(b == nil)
319 056fe1ba 2003-11-23 devnull return ~(uvlong)0;
320 056fe1ba 2003-11-23 devnull vtblockput(b);
322 056fe1ba 2003-11-23 devnull return e.size;
325 056fe1ba 2003-11-23 devnull static int
326 056fe1ba 2003-11-23 devnull shrinksize(VtFile *r, VtEntry *e, uvlong size)
328 056fe1ba 2003-11-23 devnull int i, depth, type, isdir, ppb;
329 056fe1ba 2003-11-23 devnull uvlong ptrsz;
330 056fe1ba 2003-11-23 devnull uchar score[VtScoreSize];
331 056fe1ba 2003-11-23 devnull VtBlock *b;
333 056fe1ba 2003-11-23 devnull b = vtcacheglobal(r->c, e->score, e->type);
334 056fe1ba 2003-11-23 devnull if(b == nil)
335 056fe1ba 2003-11-23 devnull return -1;
337 056fe1ba 2003-11-23 devnull ptrsz = e->dsize;
338 056fe1ba 2003-11-23 devnull ppb = e->psize/VtScoreSize;
339 056fe1ba 2003-11-23 devnull type = e->type;
340 056fe1ba 2003-11-23 devnull depth = DEPTH(type);
341 056fe1ba 2003-11-23 devnull for(i=0; i+1<depth; i++)
342 056fe1ba 2003-11-23 devnull ptrsz *= ppb;
344 056fe1ba 2003-11-23 devnull isdir = r->dir;
345 056fe1ba 2003-11-23 devnull while(depth > 0){
346 056fe1ba 2003-11-23 devnull if(b->addr == NilBlock){
347 056fe1ba 2003-11-23 devnull /* not worth copying the block just so we can zero some of it */
348 056fe1ba 2003-11-23 devnull vtblockput(b);
349 056fe1ba 2003-11-23 devnull return -1;
353 056fe1ba 2003-11-23 devnull * invariant: each pointer in the tree rooted at b accounts for ptrsz bytes
356 056fe1ba 2003-11-23 devnull /* zero the pointers to unnecessary blocks */
357 056fe1ba 2003-11-23 devnull i = (size+ptrsz-1)/ptrsz;
358 056fe1ba 2003-11-23 devnull for(; i<ppb; i++)
359 056fe1ba 2003-11-23 devnull memmove(b->data+i*VtScoreSize, vtzeroscore, VtScoreSize);
361 056fe1ba 2003-11-23 devnull /* recurse (go around again) on the partially necessary block */
362 056fe1ba 2003-11-23 devnull i = size/ptrsz;
363 056fe1ba 2003-11-23 devnull size = size%ptrsz;
364 056fe1ba 2003-11-23 devnull if(size == 0){
365 056fe1ba 2003-11-23 devnull vtblockput(b);
366 056fe1ba 2003-11-23 devnull return 0;
368 056fe1ba 2003-11-23 devnull ptrsz /= ppb;
370 056fe1ba 2003-11-23 devnull memmove(score, b->data+i*VtScoreSize, VtScoreSize);
371 056fe1ba 2003-11-23 devnull vtblockput(b);
372 056fe1ba 2003-11-23 devnull b = vtcacheglobal(r->c, score, type);
373 056fe1ba 2003-11-23 devnull if(b == nil)
374 056fe1ba 2003-11-23 devnull return -1;
377 056fe1ba 2003-11-23 devnull if(b->addr == NilBlock){
378 056fe1ba 2003-11-23 devnull vtblockput(b);
379 056fe1ba 2003-11-23 devnull return -1;
383 056fe1ba 2003-11-23 devnull * No one ever truncates BtDir blocks.
385 056fe1ba 2003-11-23 devnull if(depth==0 && !isdir && e->dsize > size)
386 056fe1ba 2003-11-23 devnull memset(b->data+size, 0, e->dsize-size);
387 056fe1ba 2003-11-23 devnull vtblockput(b);
388 056fe1ba 2003-11-23 devnull return 0;
392 056fe1ba 2003-11-23 devnull vtfilesetsize(VtFile *r, uvlong size)
394 056fe1ba 2003-11-23 devnull int depth, edepth;
395 056fe1ba 2003-11-23 devnull VtEntry e;
396 056fe1ba 2003-11-23 devnull VtBlock *b;
398 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
399 056fe1ba 2003-11-23 devnull if(size == 0)
400 056fe1ba 2003-11-23 devnull return vtfiletruncate(r);
402 056fe1ba 2003-11-23 devnull if(size > VtMaxFileSize || size > ((uvlong)MaxBlock)*r->dsize){
403 056fe1ba 2003-11-23 devnull werrstr(ETooBig);
404 056fe1ba 2003-11-23 devnull return -1;
407 056fe1ba 2003-11-23 devnull b = fileload(r, &e);
408 056fe1ba 2003-11-23 devnull if(b == nil)
409 056fe1ba 2003-11-23 devnull return -1;
411 056fe1ba 2003-11-23 devnull /* quick out */
412 056fe1ba 2003-11-23 devnull if(e.size == size){
413 056fe1ba 2003-11-23 devnull vtblockput(b);
414 056fe1ba 2003-11-23 devnull return 0;
417 056fe1ba 2003-11-23 devnull depth = sizetodepth(size, e.psize, e.dsize);
418 056fe1ba 2003-11-23 devnull edepth = DEPTH(e.type);
419 056fe1ba 2003-11-23 devnull if(depth < edepth){
420 056fe1ba 2003-11-23 devnull if(shrinkdepth(r, b, &e, depth) < 0){
421 056fe1ba 2003-11-23 devnull vtblockput(b);
422 056fe1ba 2003-11-23 devnull return -1;
424 056fe1ba 2003-11-23 devnull }else if(depth > edepth){
425 056fe1ba 2003-11-23 devnull if(growdepth(r, b, &e, depth) < 0){
426 056fe1ba 2003-11-23 devnull vtblockput(b);
427 056fe1ba 2003-11-23 devnull return -1;
431 056fe1ba 2003-11-23 devnull if(size < e.size)
432 056fe1ba 2003-11-23 devnull shrinksize(r, &e, size);
434 056fe1ba 2003-11-23 devnull e.size = size;
435 056fe1ba 2003-11-23 devnull vtentrypack(&e, b->data, r->offset % r->epb);
436 056fe1ba 2003-11-23 devnull vtblockput(b);
438 056fe1ba 2003-11-23 devnull return 0;
442 056fe1ba 2003-11-23 devnull vtfilesetdirsize(VtFile *r, u32int ds)
444 056fe1ba 2003-11-23 devnull uvlong size;
445 056fe1ba 2003-11-23 devnull int epb;
447 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
448 056fe1ba 2003-11-23 devnull epb = r->dsize/VtEntrySize;
450 056fe1ba 2003-11-23 devnull size = (uvlong)r->dsize*(ds/epb);
451 056fe1ba 2003-11-23 devnull size += VtEntrySize*(ds%epb);
452 056fe1ba 2003-11-23 devnull return vtfilesetsize(r, size);
456 056fe1ba 2003-11-23 devnull vtfilegetdirsize(VtFile *r)
458 056fe1ba 2003-11-23 devnull ulong ds;
459 056fe1ba 2003-11-23 devnull uvlong size;
460 056fe1ba 2003-11-23 devnull int epb;
462 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
463 056fe1ba 2003-11-23 devnull epb = r->dsize/VtEntrySize;
465 056fe1ba 2003-11-23 devnull size = vtfilegetsize(r);
466 056fe1ba 2003-11-23 devnull ds = epb*(size/r->dsize);
467 056fe1ba 2003-11-23 devnull ds += (size%r->dsize)/VtEntrySize;
468 056fe1ba 2003-11-23 devnull return ds;
472 056fe1ba 2003-11-23 devnull vtfilegetentry(VtFile *r, VtEntry *e)
474 056fe1ba 2003-11-23 devnull VtBlock *b;
476 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
477 056fe1ba 2003-11-23 devnull b = fileload(r, e);
478 056fe1ba 2003-11-23 devnull if(b == nil)
479 056fe1ba 2003-11-23 devnull return -1;
480 056fe1ba 2003-11-23 devnull vtblockput(b);
482 056fe1ba 2003-11-23 devnull return 0;
486 056fe1ba 2003-11-23 devnull vtfilesetentry(VtFile *r, VtEntry *e)
488 056fe1ba 2003-11-23 devnull VtBlock *b;
489 056fe1ba 2003-11-23 devnull VtEntry ee;
491 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
492 056fe1ba 2003-11-23 devnull b = fileload(r, &ee);
493 056fe1ba 2003-11-23 devnull if(b == nil)
494 056fe1ba 2003-11-23 devnull return -1;
495 056fe1ba 2003-11-23 devnull vtentrypack(e, b->data, r->offset % r->epb);
496 056fe1ba 2003-11-23 devnull vtblockput(b);
497 056fe1ba 2003-11-23 devnull return 0;
500 056fe1ba 2003-11-23 devnull static VtBlock *
501 056fe1ba 2003-11-23 devnull blockwalk(VtBlock *p, int index, VtCache *c, int mode, VtEntry *e)
503 056fe1ba 2003-11-23 devnull VtBlock *b;
504 056fe1ba 2003-11-23 devnull int type;
505 056fe1ba 2003-11-23 devnull uchar *score;
506 056fe1ba 2003-11-23 devnull VtEntry oe;
508 056fe1ba 2003-11-23 devnull switch(p->type){
509 056fe1ba 2003-11-23 devnull case VtDataType:
510 056fe1ba 2003-11-23 devnull assert(0);
511 056fe1ba 2003-11-23 devnull case VtDirType:
512 056fe1ba 2003-11-23 devnull type = e->type;
513 056fe1ba 2003-11-23 devnull score = e->score;
515 056fe1ba 2003-11-23 devnull default:
516 056fe1ba 2003-11-23 devnull type = p->type - 1;
517 056fe1ba 2003-11-23 devnull score = p->data+index*VtScoreSize;
520 056fe1ba 2003-11-23 devnull //print("walk from %V/%d ty %d to %V ty %d\n", p->score, index, p->type, score, type);
522 056fe1ba 2003-11-23 devnull if(mode == VtOWRITE && vtglobaltolocal(score) == NilBlock){
523 056fe1ba 2003-11-23 devnull b = vtcacheallocblock(c, type);
525 056fe1ba 2003-11-23 devnull goto HaveCopy;
527 056fe1ba 2003-11-23 devnull b = vtcacheglobal(c, score, type);
529 056fe1ba 2003-11-23 devnull if(b == nil || mode == VtOREAD)
530 056fe1ba 2003-11-23 devnull return b;
532 056fe1ba 2003-11-23 devnull if(vtglobaltolocal(b->score) != NilBlock)
533 056fe1ba 2003-11-23 devnull return b;
535 056fe1ba 2003-11-23 devnull oe = *e;
538 056fe1ba 2003-11-23 devnull * Copy on write.
540 056fe1ba 2003-11-23 devnull e->flags |= VtEntryLocal;
542 056fe1ba 2003-11-23 devnull b = vtblockcopy(b/*, e->tag, fs->ehi, fs->elo*/);
543 056fe1ba 2003-11-23 devnull if(b == nil)
544 056fe1ba 2003-11-23 devnull return nil;
546 056fe1ba 2003-11-23 devnull HaveCopy:
547 056fe1ba 2003-11-23 devnull if(p->type == VtDirType){
548 056fe1ba 2003-11-23 devnull memmove(e->score, b->score, VtScoreSize);
549 056fe1ba 2003-11-23 devnull vtentrypack(e, p->data, index);
551 056fe1ba 2003-11-23 devnull memmove(p->data+index*VtScoreSize, b->score, VtScoreSize);
553 056fe1ba 2003-11-23 devnull return b;
557 056fe1ba 2003-11-23 devnull * Change the depth of the VtFile r.
558 056fe1ba 2003-11-23 devnull * The entry e for r is contained in block p.
560 056fe1ba 2003-11-23 devnull static int
561 056fe1ba 2003-11-23 devnull growdepth(VtFile *r, VtBlock *p, VtEntry *e, int depth)
563 056fe1ba 2003-11-23 devnull VtBlock *b, *bb;
564 056fe1ba 2003-11-23 devnull VtEntry oe;
566 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
567 056fe1ba 2003-11-23 devnull assert(depth <= VtPointerDepth);
569 056fe1ba 2003-11-23 devnull b = vtcacheglobal(r->c, e->score, e->type);
570 056fe1ba 2003-11-23 devnull if(b == nil)
571 056fe1ba 2003-11-23 devnull return -1;
573 056fe1ba 2003-11-23 devnull oe = *e;
576 056fe1ba 2003-11-23 devnull * Keep adding layers until we get to the right depth
577 056fe1ba 2003-11-23 devnull * or an error occurs.
579 056fe1ba 2003-11-23 devnull while(DEPTH(e->type) < depth){
580 056fe1ba 2003-11-23 devnull bb = vtcacheallocblock(r->c, e->type+1);
581 056fe1ba 2003-11-23 devnull if(bb == nil)
583 056fe1ba 2003-11-23 devnull memmove(bb->data, b->score, VtScoreSize);
584 056fe1ba 2003-11-23 devnull memmove(e->score, bb->score, VtScoreSize);
585 056fe1ba 2003-11-23 devnull e->type++;
586 056fe1ba 2003-11-23 devnull e->flags |= VtEntryLocal;
587 056fe1ba 2003-11-23 devnull vtblockput(b);
591 056fe1ba 2003-11-23 devnull vtentrypack(e, p->data, r->offset % r->epb);
592 056fe1ba 2003-11-23 devnull vtblockput(b);
594 056fe1ba 2003-11-23 devnull if(DEPTH(e->type) == depth)
595 056fe1ba 2003-11-23 devnull return 0;
596 056fe1ba 2003-11-23 devnull return -1;
599 056fe1ba 2003-11-23 devnull static int
600 056fe1ba 2003-11-23 devnull shrinkdepth(VtFile *r, VtBlock *p, VtEntry *e, int depth)
602 056fe1ba 2003-11-23 devnull VtBlock *b, *nb, *ob, *rb;
603 056fe1ba 2003-11-23 devnull VtEntry oe;
605 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
606 056fe1ba 2003-11-23 devnull assert(depth <= VtPointerDepth);
608 056fe1ba 2003-11-23 devnull rb = vtcacheglobal(r->c, e->score, e->type);
609 056fe1ba 2003-11-23 devnull if(rb == nil)
610 056fe1ba 2003-11-23 devnull return 0;
613 056fe1ba 2003-11-23 devnull * Walk down to the new root block.
614 056fe1ba 2003-11-23 devnull * We may stop early, but something is better than nothing.
616 056fe1ba 2003-11-23 devnull oe = *e;
618 056fe1ba 2003-11-23 devnull ob = nil;
620 056fe1ba 2003-11-23 devnull for(; DEPTH(e->type) > depth; e->type--){
621 056fe1ba 2003-11-23 devnull nb = vtcacheglobal(r->c, b->data, e->type-1);
622 056fe1ba 2003-11-23 devnull if(nb == nil)
624 056fe1ba 2003-11-23 devnull if(ob!=nil && ob!=rb)
625 056fe1ba 2003-11-23 devnull vtblockput(ob);
630 056fe1ba 2003-11-23 devnull if(b == rb){
631 056fe1ba 2003-11-23 devnull vtblockput(rb);
632 056fe1ba 2003-11-23 devnull return 0;
636 056fe1ba 2003-11-23 devnull * Right now, e points at the root block rb, b is the new root block,
637 056fe1ba 2003-11-23 devnull * and ob points at b. To update:
639 056fe1ba 2003-11-23 devnull * (i) change e to point at b
640 056fe1ba 2003-11-23 devnull * (ii) zero the pointer ob -> b
641 056fe1ba 2003-11-23 devnull * (iii) free the root block
643 056fe1ba 2003-11-23 devnull * p (the block containing e) must be written before
644 056fe1ba 2003-11-23 devnull * anything else.
647 056fe1ba 2003-11-23 devnull /* (i) */
648 056fe1ba 2003-11-23 devnull memmove(e->score, b->score, VtScoreSize);
649 056fe1ba 2003-11-23 devnull vtentrypack(e, p->data, r->offset % r->epb);
651 056fe1ba 2003-11-23 devnull /* (ii) */
652 056fe1ba 2003-11-23 devnull memmove(ob->data, vtzeroscore, VtScoreSize);
654 056fe1ba 2003-11-23 devnull /* (iii) */
655 056fe1ba 2003-11-23 devnull vtblockput(rb);
656 056fe1ba 2003-11-23 devnull if(ob!=nil && ob!=rb)
657 056fe1ba 2003-11-23 devnull vtblockput(ob);
658 056fe1ba 2003-11-23 devnull vtblockput(b);
660 056fe1ba 2003-11-23 devnull if(DEPTH(e->type) == depth)
661 056fe1ba 2003-11-23 devnull return 0;
662 056fe1ba 2003-11-23 devnull return -1;
665 056fe1ba 2003-11-23 devnull static int
666 056fe1ba 2003-11-23 devnull mkindices(VtEntry *e, u32int bn, int *index)
668 056fe1ba 2003-11-23 devnull int i, np;
670 59a96820 2004-06-17 devnull memset(index, 0, (VtPointerDepth+1)*sizeof(int));
672 056fe1ba 2003-11-23 devnull np = e->psize/VtScoreSize;
673 056fe1ba 2003-11-23 devnull for(i=0; bn > 0; i++){
674 056fe1ba 2003-11-23 devnull if(i >= VtPointerDepth){
675 d23a617a 2004-03-15 devnull werrstr("bad address 0x%lux", (ulong)bn);
676 056fe1ba 2003-11-23 devnull return -1;
678 056fe1ba 2003-11-23 devnull index[i] = bn % np;
679 056fe1ba 2003-11-23 devnull bn /= np;
681 056fe1ba 2003-11-23 devnull return i;
684 056fe1ba 2003-11-23 devnull VtBlock *
685 056fe1ba 2003-11-23 devnull vtfileblock(VtFile *r, u32int bn, int mode)
687 056fe1ba 2003-11-23 devnull VtBlock *b, *bb;
688 056fe1ba 2003-11-23 devnull int index[VtPointerDepth+1];
689 056fe1ba 2003-11-23 devnull VtEntry e;
693 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
694 056fe1ba 2003-11-23 devnull assert(bn != NilBlock);
696 056fe1ba 2003-11-23 devnull b = fileload(r, &e);
697 056fe1ba 2003-11-23 devnull if(b == nil)
698 056fe1ba 2003-11-23 devnull return nil;
700 056fe1ba 2003-11-23 devnull i = mkindices(&e, bn, index);
701 056fe1ba 2003-11-23 devnull if(i < 0)
702 056fe1ba 2003-11-23 devnull return nil;
703 056fe1ba 2003-11-23 devnull if(i > DEPTH(e.type)){
704 056fe1ba 2003-11-23 devnull if(mode == VtOREAD){
705 d23a617a 2004-03-15 devnull werrstr("bad address 0x%lux", (ulong)bn);
706 056fe1ba 2003-11-23 devnull goto Err;
708 056fe1ba 2003-11-23 devnull index[i] = 0;
709 056fe1ba 2003-11-23 devnull if(growdepth(r, b, &e, i) < 0)
710 056fe1ba 2003-11-23 devnull goto Err;
713 056fe1ba 2003-11-23 devnull assert(b->type == VtDirType);
715 056fe1ba 2003-11-23 devnull index[DEPTH(e.type)] = r->offset % r->epb;
717 056fe1ba 2003-11-23 devnull /* mode for intermediate block */
718 056fe1ba 2003-11-23 devnull m = mode;
719 056fe1ba 2003-11-23 devnull if(m == VtOWRITE)
720 056fe1ba 2003-11-23 devnull m = VtORDWR;
722 056fe1ba 2003-11-23 devnull for(i=DEPTH(e.type); i>=0; i--){
723 056fe1ba 2003-11-23 devnull bb = blockwalk(b, index[i], r->c, i==0 ? mode : m, &e);
724 056fe1ba 2003-11-23 devnull if(bb == nil)
725 056fe1ba 2003-11-23 devnull goto Err;
726 056fe1ba 2003-11-23 devnull vtblockput(b);
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 056fe1ba 2003-11-23 devnull i = mkindices(&e, bn, index);
751 056fe1ba 2003-11-23 devnull if(i < 0){
752 056fe1ba 2003-11-23 devnull vtblockput(b);
753 056fe1ba 2003-11-23 devnull return -1;
755 056fe1ba 2003-11-23 devnull if(i > DEPTH(e.type)){
756 056fe1ba 2003-11-23 devnull memmove(score, vtzeroscore, VtScoreSize);
757 056fe1ba 2003-11-23 devnull vtblockput(b);
758 056fe1ba 2003-11-23 devnull return 0;
761 056fe1ba 2003-11-23 devnull index[DEPTH(e.type)] = r->offset % r->epb;
763 056fe1ba 2003-11-23 devnull for(i=DEPTH(e.type); i>=1; i--){
764 056fe1ba 2003-11-23 devnull bb = blockwalk(b, index[i], r->c, VtOREAD, &e);
765 056fe1ba 2003-11-23 devnull if(bb == nil)
766 056fe1ba 2003-11-23 devnull goto Err;
767 056fe1ba 2003-11-23 devnull vtblockput(b);
769 056fe1ba 2003-11-23 devnull if(memcmp(b->score, vtzeroscore, VtScoreSize) == 0)
773 056fe1ba 2003-11-23 devnull memmove(score, b->data+index[0]*VtScoreSize, VtScoreSize);
774 056fe1ba 2003-11-23 devnull vtblockput(b);
775 056fe1ba 2003-11-23 devnull return 0;
778 056fe1ba 2003-11-23 devnull vtblockput(b);
779 056fe1ba 2003-11-23 devnull return -1;
783 056fe1ba 2003-11-23 devnull vtfileincref(VtFile *r)
785 056fe1ba 2003-11-23 devnull qlock(&r->lk);
786 056fe1ba 2003-11-23 devnull r->ref++;
787 056fe1ba 2003-11-23 devnull qunlock(&r->lk);
791 056fe1ba 2003-11-23 devnull vtfileclose(VtFile *r)
793 056fe1ba 2003-11-23 devnull if(r == nil)
795 056fe1ba 2003-11-23 devnull qlock(&r->lk);
796 056fe1ba 2003-11-23 devnull r->ref--;
797 056fe1ba 2003-11-23 devnull if(r->ref){
798 056fe1ba 2003-11-23 devnull qunlock(&r->lk);
801 056fe1ba 2003-11-23 devnull assert(r->ref == 0);
802 056fe1ba 2003-11-23 devnull qunlock(&r->lk);
803 056fe1ba 2003-11-23 devnull if(r->parent)
804 056fe1ba 2003-11-23 devnull vtfileclose(r->parent);
805 056fe1ba 2003-11-23 devnull memset(r, ~0, sizeof(*r));
806 056fe1ba 2003-11-23 devnull vtfree(r);
810 056fe1ba 2003-11-23 devnull * Retrieve the block containing the entry for r.
811 056fe1ba 2003-11-23 devnull * If a snapshot has happened, we might need
812 056fe1ba 2003-11-23 devnull * to get a new copy of the block. We avoid this
813 056fe1ba 2003-11-23 devnull * in the common case by caching the score for
814 056fe1ba 2003-11-23 devnull * the block and the last epoch in which it was valid.
816 056fe1ba 2003-11-23 devnull * We use r->mode to tell the difference between active
817 056fe1ba 2003-11-23 devnull * file system VtFiles (VtORDWR) and VtFiles for the
818 056fe1ba 2003-11-23 devnull * snapshot file system (VtOREAD).
820 056fe1ba 2003-11-23 devnull static VtBlock*
821 056fe1ba 2003-11-23 devnull fileloadblock(VtFile *r, int mode)
823 056fe1ba 2003-11-23 devnull char e[ERRMAX];
824 056fe1ba 2003-11-23 devnull u32int addr;
825 056fe1ba 2003-11-23 devnull VtBlock *b;
827 056fe1ba 2003-11-23 devnull switch(r->mode){
828 056fe1ba 2003-11-23 devnull default:
829 056fe1ba 2003-11-23 devnull assert(0);
830 056fe1ba 2003-11-23 devnull case VtORDWR:
831 056fe1ba 2003-11-23 devnull assert(r->mode == VtORDWR);
832 056fe1ba 2003-11-23 devnull if(r->local == 1){
833 056fe1ba 2003-11-23 devnull b = vtcacheglobal(r->c, r->score, VtDirType);
834 056fe1ba 2003-11-23 devnull if(b == nil)
835 056fe1ba 2003-11-23 devnull return nil;
836 056fe1ba 2003-11-23 devnull return b;
838 056fe1ba 2003-11-23 devnull assert(r->parent != nil);
839 056fe1ba 2003-11-23 devnull if(vtfilelock(r->parent, VtORDWR) < 0)
840 056fe1ba 2003-11-23 devnull return nil;
841 056fe1ba 2003-11-23 devnull b = vtfileblock(r->parent, r->offset/r->epb, VtORDWR);
842 056fe1ba 2003-11-23 devnull vtfileunlock(r->parent);
843 056fe1ba 2003-11-23 devnull if(b == nil)
844 056fe1ba 2003-11-23 devnull return nil;
845 056fe1ba 2003-11-23 devnull memmove(r->score, b->score, VtScoreSize);
846 056fe1ba 2003-11-23 devnull r->local = 1;
847 056fe1ba 2003-11-23 devnull return b;
849 056fe1ba 2003-11-23 devnull case VtOREAD:
850 056fe1ba 2003-11-23 devnull if(mode == VtORDWR){
851 056fe1ba 2003-11-23 devnull werrstr("read/write lock of read-only file");
852 056fe1ba 2003-11-23 devnull return nil;
854 056fe1ba 2003-11-23 devnull addr = vtglobaltolocal(r->score);
855 056fe1ba 2003-11-23 devnull if(addr == NilBlock)
856 056fe1ba 2003-11-23 devnull return vtcacheglobal(r->c, r->score, VtDirType);
858 056fe1ba 2003-11-23 devnull b = vtcachelocal(r->c, addr, VtDirType);
860 056fe1ba 2003-11-23 devnull return b;
863 056fe1ba 2003-11-23 devnull * If it failed because the epochs don't match, the block has been
864 056fe1ba 2003-11-23 devnull * archived and reclaimed. Rewalk from the parent and get the
865 056fe1ba 2003-11-23 devnull * new pointer. This can't happen in the VtORDWR case
866 056fe1ba 2003-11-23 devnull * above because blocks in the current epoch don't get
867 056fe1ba 2003-11-23 devnull * reclaimed. The fact that we're VtOREAD means we're
868 056fe1ba 2003-11-23 devnull * a snapshot. (Or else the file system is read-only, but then
869 056fe1ba 2003-11-23 devnull * the archiver isn't going around deleting blocks.)
871 056fe1ba 2003-11-23 devnull rerrstr(e, sizeof e);
872 056fe1ba 2003-11-23 devnull if(strcmp(e, ELabelMismatch) == 0){
873 056fe1ba 2003-11-23 devnull if(vtfilelock(r->parent, VtOREAD) < 0)
874 056fe1ba 2003-11-23 devnull return nil;
875 056fe1ba 2003-11-23 devnull b = vtfileblock(r->parent, r->offset/r->epb, VtOREAD);
876 056fe1ba 2003-11-23 devnull vtfileunlock(r->parent);
878 056fe1ba 2003-11-23 devnull fprint(2, "vtfilealloc: lost %V found %V\n",
879 056fe1ba 2003-11-23 devnull r->score, b->score);
880 056fe1ba 2003-11-23 devnull memmove(r->score, b->score, VtScoreSize);
881 056fe1ba 2003-11-23 devnull return b;
884 056fe1ba 2003-11-23 devnull return nil;
889 056fe1ba 2003-11-23 devnull vtfilelock(VtFile *r, int mode)
891 056fe1ba 2003-11-23 devnull VtBlock *b;
893 056fe1ba 2003-11-23 devnull if(mode == -1)
894 056fe1ba 2003-11-23 devnull mode = r->mode;
896 056fe1ba 2003-11-23 devnull b = fileloadblock(r, mode);
897 056fe1ba 2003-11-23 devnull if(b == nil)
898 056fe1ba 2003-11-23 devnull return -1;
900 056fe1ba 2003-11-23 devnull * The fact that we are holding b serves as the
901 056fe1ba 2003-11-23 devnull * lock entitling us to write to r->b.
903 056fe1ba 2003-11-23 devnull assert(r->b == nil);
904 056fe1ba 2003-11-23 devnull r->b = b;
905 056fe1ba 2003-11-23 devnull return 0;
909 056fe1ba 2003-11-23 devnull * Lock two (usually sibling) VtFiles. This needs special care
910 056fe1ba 2003-11-23 devnull * because the Entries for both vtFiles might be in the same block.
911 056fe1ba 2003-11-23 devnull * We also try to lock blocks in left-to-right order within the tree.
914 056fe1ba 2003-11-23 devnull vtfilelock2(VtFile *r, VtFile *rr, int mode)
916 056fe1ba 2003-11-23 devnull VtBlock *b, *bb;
918 056fe1ba 2003-11-23 devnull if(rr == nil)
919 056fe1ba 2003-11-23 devnull return vtfilelock(r, mode);
921 056fe1ba 2003-11-23 devnull if(mode == -1)
922 056fe1ba 2003-11-23 devnull mode = r->mode;
924 056fe1ba 2003-11-23 devnull if(r->parent==rr->parent && r->offset/r->epb == rr->offset/rr->epb){
925 056fe1ba 2003-11-23 devnull b = fileloadblock(r, mode);
926 056fe1ba 2003-11-23 devnull if(b == nil)
927 056fe1ba 2003-11-23 devnull return -1;
928 056fe1ba 2003-11-23 devnull vtblockduplock(b);
930 056fe1ba 2003-11-23 devnull }else if(r->parent==rr->parent || r->offset > rr->offset){
931 056fe1ba 2003-11-23 devnull bb = fileloadblock(rr, mode);
932 056fe1ba 2003-11-23 devnull b = fileloadblock(r, mode);
934 056fe1ba 2003-11-23 devnull b = fileloadblock(r, mode);
935 056fe1ba 2003-11-23 devnull bb = fileloadblock(rr, mode);
937 056fe1ba 2003-11-23 devnull if(b == nil || bb == nil){
939 056fe1ba 2003-11-23 devnull vtblockput(b);
941 056fe1ba 2003-11-23 devnull vtblockput(bb);
942 056fe1ba 2003-11-23 devnull return -1;
946 056fe1ba 2003-11-23 devnull * The fact that we are holding b and bb serves
947 056fe1ba 2003-11-23 devnull * as the lock entitling us to write to r->b and rr->b.
949 056fe1ba 2003-11-23 devnull r->b = b;
950 056fe1ba 2003-11-23 devnull rr->b = bb;
951 056fe1ba 2003-11-23 devnull return 0;
955 056fe1ba 2003-11-23 devnull vtfileunlock(VtFile *r)
957 056fe1ba 2003-11-23 devnull VtBlock *b;
959 056fe1ba 2003-11-23 devnull if(r->b == nil){
960 056fe1ba 2003-11-23 devnull fprint(2, "vtfileunlock: already unlocked\n");
961 056fe1ba 2003-11-23 devnull abort();
963 056fe1ba 2003-11-23 devnull b = r->b;
964 056fe1ba 2003-11-23 devnull r->b = nil;
965 056fe1ba 2003-11-23 devnull vtblockput(b);
968 056fe1ba 2003-11-23 devnull static VtBlock*
969 056fe1ba 2003-11-23 devnull fileload(VtFile *r, VtEntry *e)
971 056fe1ba 2003-11-23 devnull VtBlock *b;
973 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
974 056fe1ba 2003-11-23 devnull b = r->b;
975 056fe1ba 2003-11-23 devnull if(vtentryunpack(e, b->data, r->offset % r->epb) < 0)
976 056fe1ba 2003-11-23 devnull return nil;
977 056fe1ba 2003-11-23 devnull vtblockduplock(b);
978 056fe1ba 2003-11-23 devnull return b;
981 056fe1ba 2003-11-23 devnull static int
982 056fe1ba 2003-11-23 devnull sizetodepth(uvlong s, int psize, int dsize)
987 056fe1ba 2003-11-23 devnull /* determine pointer depth */
988 056fe1ba 2003-11-23 devnull np = psize/VtScoreSize;
989 056fe1ba 2003-11-23 devnull s = (s + dsize - 1)/dsize;
990 056fe1ba 2003-11-23 devnull for(d = 0; s > 1; d++)
991 056fe1ba 2003-11-23 devnull s = (s + np - 1)/np;
992 056fe1ba 2003-11-23 devnull return d;
996 056fe1ba 2003-11-23 devnull vtfileread(VtFile *f, void *data, long count, vlong offset)
998 056fe1ba 2003-11-23 devnull int frag;
999 056fe1ba 2003-11-23 devnull VtBlock *b;
1000 056fe1ba 2003-11-23 devnull VtEntry e;
1002 056fe1ba 2003-11-23 devnull assert(ISLOCKED(f));
1004 056fe1ba 2003-11-23 devnull vtfilegetentry(f, &e);
1005 056fe1ba 2003-11-23 devnull if(count == 0)
1006 056fe1ba 2003-11-23 devnull return 0;
1007 056fe1ba 2003-11-23 devnull if(count < 0 || offset < 0){
1008 056fe1ba 2003-11-23 devnull werrstr("vtfileread: bad offset or count");
1009 056fe1ba 2003-11-23 devnull return -1;
1011 056fe1ba 2003-11-23 devnull if(offset >= e.size)
1012 056fe1ba 2003-11-23 devnull return 0;
1014 056fe1ba 2003-11-23 devnull if(offset+count > e.size)
1015 056fe1ba 2003-11-23 devnull count = e.size - offset;
1017 056fe1ba 2003-11-23 devnull frag = offset % e.dsize;
1018 056fe1ba 2003-11-23 devnull if(frag+count > e.dsize)
1019 056fe1ba 2003-11-23 devnull count = e.dsize - frag;
1021 056fe1ba 2003-11-23 devnull b = vtfileblock(f, offset/e.dsize, VtOREAD);
1022 056fe1ba 2003-11-23 devnull if(b == nil)
1023 056fe1ba 2003-11-23 devnull return -1;
1025 056fe1ba 2003-11-23 devnull memmove(data, b->data+frag, count);
1026 056fe1ba 2003-11-23 devnull vtblockput(b);
1027 056fe1ba 2003-11-23 devnull return count;
1030 056fe1ba 2003-11-23 devnull static long
1031 056fe1ba 2003-11-23 devnull filewrite1(VtFile *f, void *data, long count, vlong offset)
1033 056fe1ba 2003-11-23 devnull int frag, m;
1034 056fe1ba 2003-11-23 devnull VtBlock *b;
1035 056fe1ba 2003-11-23 devnull VtEntry e;
1037 056fe1ba 2003-11-23 devnull vtfilegetentry(f, &e);
1038 056fe1ba 2003-11-23 devnull if(count < 0 || offset < 0){
1039 056fe1ba 2003-11-23 devnull werrstr("vtfilewrite: bad offset or count");
1040 056fe1ba 2003-11-23 devnull return -1;
1043 056fe1ba 2003-11-23 devnull frag = offset % e.dsize;
1044 056fe1ba 2003-11-23 devnull if(frag+count > e.dsize)
1045 056fe1ba 2003-11-23 devnull count = e.dsize - frag;
1047 056fe1ba 2003-11-23 devnull m = VtORDWR;
1048 056fe1ba 2003-11-23 devnull if(frag == 0 && count == e.dsize)
1049 056fe1ba 2003-11-23 devnull m = VtOWRITE;
1051 056fe1ba 2003-11-23 devnull b = vtfileblock(f, offset/e.dsize, m);
1052 056fe1ba 2003-11-23 devnull if(b == nil)
1053 056fe1ba 2003-11-23 devnull return -1;
1055 056fe1ba 2003-11-23 devnull memmove(b->data+frag, data, count);
1057 056fe1ba 2003-11-23 devnull if(offset+count > e.size){
1058 056fe1ba 2003-11-23 devnull vtfilegetentry(f, &e);
1059 056fe1ba 2003-11-23 devnull e.size = offset+count;
1060 056fe1ba 2003-11-23 devnull vtfilesetentry(f, &e);
1063 056fe1ba 2003-11-23 devnull vtblockput(b);
1064 056fe1ba 2003-11-23 devnull return count;
1068 056fe1ba 2003-11-23 devnull vtfilewrite(VtFile *f, void *data, long count, vlong offset)
1070 056fe1ba 2003-11-23 devnull long tot, m;
1072 056fe1ba 2003-11-23 devnull assert(ISLOCKED(f));
1074 056fe1ba 2003-11-23 devnull tot = 0;
1076 056fe1ba 2003-11-23 devnull while(tot < count){
1077 056fe1ba 2003-11-23 devnull m = filewrite1(f, (char*)data+tot, count-tot, offset+tot);
1078 056fe1ba 2003-11-23 devnull if(m <= 0)
1080 056fe1ba 2003-11-23 devnull tot += m;
1082 056fe1ba 2003-11-23 devnull if(tot==0)
1083 056fe1ba 2003-11-23 devnull return m;
1084 056fe1ba 2003-11-23 devnull return tot;
1087 056fe1ba 2003-11-23 devnull static int
1088 056fe1ba 2003-11-23 devnull flushblock(VtCache *c, VtBlock *bb, uchar score[VtScoreSize], int ppb, int epb,
1089 056fe1ba 2003-11-23 devnull int type)
1091 056fe1ba 2003-11-23 devnull u32int addr;
1092 056fe1ba 2003-11-23 devnull VtBlock *b;
1093 056fe1ba 2003-11-23 devnull VtEntry e;
1096 056fe1ba 2003-11-23 devnull addr = vtglobaltolocal(score);
1097 056fe1ba 2003-11-23 devnull if(addr == NilBlock)
1098 056fe1ba 2003-11-23 devnull return 0;
1100 056fe1ba 2003-11-23 devnull if(bb){
1101 056fe1ba 2003-11-23 devnull b = bb;
1102 056fe1ba 2003-11-23 devnull if(memcmp(b->score, score, VtScoreSize) != 0)
1103 056fe1ba 2003-11-23 devnull abort();
1105 056fe1ba 2003-11-23 devnull if((b = vtcachelocal(c, addr, type)) == nil)
1106 056fe1ba 2003-11-23 devnull return -1;
1108 056fe1ba 2003-11-23 devnull switch(type){
1109 056fe1ba 2003-11-23 devnull case VtDataType:
1112 056fe1ba 2003-11-23 devnull case VtDirType:
1113 056fe1ba 2003-11-23 devnull for(i=0; i<epb; i++){
1114 056fe1ba 2003-11-23 devnull if(vtentryunpack(&e, b->data, i) < 0)
1115 056fe1ba 2003-11-23 devnull goto Err;
1116 056fe1ba 2003-11-23 devnull if(flushblock(c, nil, e.score, e.psize/VtScoreSize, e.dsize/VtEntrySize,
1117 056fe1ba 2003-11-23 devnull e.type) < 0)
1118 056fe1ba 2003-11-23 devnull goto Err;
1122 056fe1ba 2003-11-23 devnull default: /* VtPointerTypeX */
1123 056fe1ba 2003-11-23 devnull for(i=0; i<ppb; i++){
1124 056fe1ba 2003-11-23 devnull if(flushblock(c, nil, b->data+VtScoreSize*i, ppb, epb, type-1) < 0)
1125 056fe1ba 2003-11-23 devnull goto Err;
1130 056fe1ba 2003-11-23 devnull if(vtblockwrite(b) < 0)
1131 056fe1ba 2003-11-23 devnull goto Err;
1132 056fe1ba 2003-11-23 devnull memmove(score, b->score, VtScoreSize);
1133 056fe1ba 2003-11-23 devnull if(b != bb)
1134 056fe1ba 2003-11-23 devnull vtblockput(b);
1135 056fe1ba 2003-11-23 devnull return 0;
1138 056fe1ba 2003-11-23 devnull if(b != bb)
1139 056fe1ba 2003-11-23 devnull vtblockput(b);
1140 056fe1ba 2003-11-23 devnull return -1;
1144 056fe1ba 2003-11-23 devnull vtfileflush(VtFile *f)
1146 056fe1ba 2003-11-23 devnull int ret;
1147 056fe1ba 2003-11-23 devnull VtBlock *b;
1148 056fe1ba 2003-11-23 devnull VtEntry e;
1150 056fe1ba 2003-11-23 devnull assert(ISLOCKED(f));
1151 056fe1ba 2003-11-23 devnull b = fileload(f, &e);
1152 056fe1ba 2003-11-23 devnull if(!(e.flags&VtEntryLocal)){
1153 056fe1ba 2003-11-23 devnull vtblockput(b);
1154 056fe1ba 2003-11-23 devnull return 0;
1157 056fe1ba 2003-11-23 devnull ret = flushblock(f->c, nil, e.score, e.psize/VtScoreSize, e.dsize/VtEntrySize,
1158 056fe1ba 2003-11-23 devnull e.type);
1159 7cb74894 2004-06-17 devnull if(ret < 0){
1160 056fe1ba 2003-11-23 devnull vtblockput(b);
1161 056fe1ba 2003-11-23 devnull return -1;
1164 056fe1ba 2003-11-23 devnull vtentrypack(&e, b->data, f->offset % f->epb);
1165 056fe1ba 2003-11-23 devnull vtblockput(b);
1166 056fe1ba 2003-11-23 devnull return 0;
1170 056fe1ba 2003-11-23 devnull vtfileflushbefore(VtFile *r, u64int offset)
1172 056fe1ba 2003-11-23 devnull VtBlock *b, *bb;
1173 056fe1ba 2003-11-23 devnull VtEntry e;
1174 59a96820 2004-06-17 devnull int i, base, depth, ppb, epb, doflush;
1175 59a96820 2004-06-17 devnull int index[VtPointerDepth+1], j, ret;
1176 056fe1ba 2003-11-23 devnull VtBlock *bi[VtPointerDepth+2];
1177 056fe1ba 2003-11-23 devnull uchar *score;
1179 056fe1ba 2003-11-23 devnull assert(ISLOCKED(r));
1180 056fe1ba 2003-11-23 devnull if(offset == 0)
1181 056fe1ba 2003-11-23 devnull return 0;
1183 056fe1ba 2003-11-23 devnull b = fileload(r, &e);
1184 056fe1ba 2003-11-23 devnull if(b == nil)
1185 056fe1ba 2003-11-23 devnull return -1;
1188 59a96820 2004-06-17 devnull * compute path through tree for the last written byte and the next one.
1190 056fe1ba 2003-11-23 devnull ret = -1;
1191 056fe1ba 2003-11-23 devnull memset(bi, 0, sizeof bi);
1192 056fe1ba 2003-11-23 devnull depth = DEPTH(e.type);
1193 056fe1ba 2003-11-23 devnull bi[depth+1] = b;
1194 056fe1ba 2003-11-23 devnull i = mkindices(&e, (offset-1)/e.dsize, index);
1195 056fe1ba 2003-11-23 devnull if(i < 0)
1196 056fe1ba 2003-11-23 devnull goto Err;
1197 056fe1ba 2003-11-23 devnull if(i > depth)
1198 056fe1ba 2003-11-23 devnull goto Err;
1199 056fe1ba 2003-11-23 devnull ppb = e.psize / VtScoreSize;
1200 056fe1ba 2003-11-23 devnull epb = e.dsize / VtEntrySize;
1203 59a96820 2004-06-17 devnull * load the blocks along the last written byte
1205 056fe1ba 2003-11-23 devnull index[depth] = r->offset % r->epb;
1206 056fe1ba 2003-11-23 devnull for(i=depth; i>=0; i--){
1207 056fe1ba 2003-11-23 devnull bb = blockwalk(b, index[i], r->c, VtORDWR, &e);
1208 056fe1ba 2003-11-23 devnull if(bb == nil)
1209 056fe1ba 2003-11-23 devnull goto Err;
1210 056fe1ba 2003-11-23 devnull bi[i] = bb;
1211 056fe1ba 2003-11-23 devnull b = bb;
1213 056fe1ba 2003-11-23 devnull ret = 0;
1216 59a96820 2004-06-17 devnull * walk up the path from leaf to root, flushing anything that
1217 59a96820 2004-06-17 devnull * has been finished.
1219 056fe1ba 2003-11-23 devnull base = e.type&~VtTypeDepthMask;
1220 005ee04b 2004-06-17 devnull for(i=0; i<=depth; i++){
1221 59a96820 2004-06-17 devnull doflush = 0;
1222 056fe1ba 2003-11-23 devnull if(i == 0){
1223 59a96820 2004-06-17 devnull /* leaf: data or dir block */
1224 59a96820 2004-06-17 devnull if(offset%e.dsize == 0)
1225 59a96820 2004-06-17 devnull doflush = 1;
1228 59a96820 2004-06-17 devnull * interior node: pointer blocks.
1229 59a96820 2004-06-17 devnull * specifically, b = bi[i] is a block whose index[i-1]'th entry
1230 59a96820 2004-06-17 devnull * points at bi[i-1].
1232 056fe1ba 2003-11-23 devnull b = bi[i];
1235 59a96820 2004-06-17 devnull * the index entries up to but not including index[i-1] point at
1236 59a96820 2004-06-17 devnull * finished blocks, so flush them for sure.
1238 056fe1ba 2003-11-23 devnull for(j=0; j<index[i-1]; j++)
1239 056fe1ba 2003-11-23 devnull if(flushblock(r->c, nil, b->data+j*VtScoreSize, ppb, epb, base+i-1) < 0)
1240 056fe1ba 2003-11-23 devnull goto Err;
1243 59a96820 2004-06-17 devnull * if index[i-1] is the last entry in the block and is global
1244 59a96820 2004-06-17 devnull * (i.e. the kid is flushed), then we can flush this block.
1246 59a96820 2004-06-17 devnull if(j==ppb-1 && vtglobaltolocal(b->data+j*VtScoreSize)==NilBlock)
1247 59a96820 2004-06-17 devnull doflush = 1;
1249 59a96820 2004-06-17 devnull if(doflush){
1250 056fe1ba 2003-11-23 devnull if(i == depth)
1251 056fe1ba 2003-11-23 devnull score = e.score;
1253 056fe1ba 2003-11-23 devnull score = bi[i+1]->data+index[i]*VtScoreSize;
1254 056fe1ba 2003-11-23 devnull if(flushblock(r->c, bi[i], score, ppb, epb, base+i) < 0)
1255 056fe1ba 2003-11-23 devnull goto Err;
1260 056fe1ba 2003-11-23 devnull /* top: entry. do this always so that the score is up-to-date */
1261 056fe1ba 2003-11-23 devnull vtentrypack(&e, bi[depth+1]->data, index[depth]);
1262 056fe1ba 2003-11-23 devnull for(i=0; i<nelem(bi); i++)
1263 056fe1ba 2003-11-23 devnull if(bi[i])
1264 056fe1ba 2003-11-23 devnull vtblockput(bi[i]);
1265 056fe1ba 2003-11-23 devnull return ret;
