1 0c98da8b 2005-07-13 devnull #include <u.h>
  2 0c98da8b 2005-07-13 devnull #include <libc.h>
  3 0c98da8b 2005-07-13 devnull #include <diskfs.h>
  4 0c98da8b 2005-07-13 devnull #include <venti.h>
  5 0c98da8b 2005-07-13 devnull 
  6 0c98da8b 2005-07-13 devnull extern void vtlibthread(void);
  7 0c98da8b 2005-07-13 devnull 
  8 0c98da8b 2005-07-13 devnull typedef struct DiskVenti DiskVenti;
  9 0c98da8b 2005-07-13 devnull struct DiskVenti
 10 0c98da8b 2005-07-13 devnull {
 11 0c98da8b 2005-07-13 devnull 	Disk disk;
 12 0c98da8b 2005-07-13 devnull 	VtEntry e;
 13 0c98da8b 2005-07-13 devnull 	VtCache *c;
 14 0c98da8b 2005-07-13 devnull };
 15 0c98da8b 2005-07-13 devnull 
 16 d3285dcb 2005-12-16 devnull extern int nfilereads;
 17 6519f895 2007-11-05 rsc extern void _nfilereads_darwin_sucks(void);
 18 0c98da8b 2005-07-13 devnull 
 19 0c98da8b 2005-07-13 devnull /*
 20 0c98da8b 2005-07-13 devnull  * This part is like file.c but doesn't require storing the root block
 21 0c98da8b 2005-07-13 devnull  * in the cache permanently and doesn't care about locking since
 22 0c98da8b 2005-07-13 devnull  * all the blocks are read-only.  Perhaps at some point this functionality
 23 0c98da8b 2005-07-13 devnull  * should go into libvac in some form.
 24 0c98da8b 2005-07-13 devnull  */
 25 0c98da8b 2005-07-13 devnull static int
 26 0c98da8b 2005-07-13 devnull vtfileindices(VtEntry *e, u32int bn, int *index)
 27 0c98da8b 2005-07-13 devnull {
 28 0c98da8b 2005-07-13 devnull 	int i, np;
 29 0c98da8b 2005-07-13 devnull 
 30 0c98da8b 2005-07-13 devnull 	memset(index, 0, VtPointerDepth*sizeof(int));
 31 0c98da8b 2005-07-13 devnull 
 32 0c98da8b 2005-07-13 devnull 	np = e->psize/VtScoreSize;
 33 0c98da8b 2005-07-13 devnull 	for(i=0; bn > 0; i++){
 34 0c98da8b 2005-07-13 devnull 		if(i >= VtPointerDepth){
 35 0c98da8b 2005-07-13 devnull 			werrstr("bad block number %lud", (ulong)bn);
 36 0c98da8b 2005-07-13 devnull 			return -1;
 37 0c98da8b 2005-07-13 devnull 		}
 38 0c98da8b 2005-07-13 devnull 		index[i] = bn % np;
 39 0c98da8b 2005-07-13 devnull 		bn /= np;
 40 0c98da8b 2005-07-13 devnull 	}
 41 0c98da8b 2005-07-13 devnull 	return i;
 42 0c98da8b 2005-07-13 devnull }
 43 0c98da8b 2005-07-13 devnull 
 44 e77222a4 2006-05-04 devnull VtBlock *_vtfileblock(VtCache*, VtEntry*, u32int);	/* avoid auto-inline by putting later in file */
 45 0c98da8b 2005-07-13 devnull static void
 46 0c98da8b 2005-07-13 devnull diskventiblockput(Block *b)
 47 0c98da8b 2005-07-13 devnull {
 48 0c98da8b 2005-07-13 devnull 	vtblockput(b->priv);
 49 0c98da8b 2005-07-13 devnull 	free(b);
 50 0c98da8b 2005-07-13 devnull }
 51 0c98da8b 2005-07-13 devnull 
 52 0c98da8b 2005-07-13 devnull static Block*
 53 0c98da8b 2005-07-13 devnull diskventiread(Disk *dd, u32int len, u64int offset)
 54 0c98da8b 2005-07-13 devnull {
 55 0c98da8b 2005-07-13 devnull 	DiskVenti *d = (DiskVenti*)dd;
 56 0c98da8b 2005-07-13 devnull 	VtBlock *vb;
 57 0c98da8b 2005-07-13 devnull 	Block *b;
 58 0c98da8b 2005-07-13 devnull 	int frag;
 59 0c98da8b 2005-07-13 devnull 
 60 0c98da8b 2005-07-13 devnull nfilereads++;
 61 0c98da8b 2005-07-13 devnull 	vb = _vtfileblock(d->c, &d->e, offset/d->e.dsize);
 62 0c98da8b 2005-07-13 devnull 	if(vb == nil)
 63 0c98da8b 2005-07-13 devnull 		return nil;
 64 0c98da8b 2005-07-13 devnull 
 65 0c98da8b 2005-07-13 devnull 	b = mallocz(sizeof(Block), 1);
 66 0c98da8b 2005-07-13 devnull 	if(b == nil){
 67 0c98da8b 2005-07-13 devnull 		vtblockput(vb);
 68 0c98da8b 2005-07-13 devnull 		return nil;
 69 0c98da8b 2005-07-13 devnull 	}
 70 0c98da8b 2005-07-13 devnull 
 71 0c98da8b 2005-07-13 devnull 	b->priv = vb;
 72 0c98da8b 2005-07-13 devnull 	b->_close = diskventiblockput;
 73 0c98da8b 2005-07-13 devnull 	frag = offset%d->e.dsize;
 74 0c98da8b 2005-07-13 devnull 	b->data = (uchar*)vb->data + frag;
 75 0c98da8b 2005-07-13 devnull 	b->len = d->e.dsize - frag;
 76 0c98da8b 2005-07-13 devnull 	if(b->len > len)
 77 0c98da8b 2005-07-13 devnull 		b->len = len;
 78 0c98da8b 2005-07-13 devnull 	return b;
 79 0c98da8b 2005-07-13 devnull }
 80 0c98da8b 2005-07-13 devnull 
 81 e77222a4 2006-05-04 devnull VtBlock*
 82 e77222a4 2006-05-04 devnull _vtfileblock(VtCache *c, VtEntry *e, u32int bn)
 83 e77222a4 2006-05-04 devnull {
 84 cd27286e 2006-05-05 devnull 	VtBlock *b;
 85 e77222a4 2006-05-04 devnull 	int i, d, index[VtPointerDepth+1], t;
 86 e77222a4 2006-05-04 devnull 	uchar score[VtScoreSize];
 87 e77222a4 2006-05-04 devnull 
 88 e77222a4 2006-05-04 devnull 	i = vtfileindices(e, bn, index);
 89 e77222a4 2006-05-04 devnull 	if(i < 0)
 90 e77222a4 2006-05-04 devnull 		return nil;
 91 e77222a4 2006-05-04 devnull 	d = (e->type&VtTypeDepthMask);
 92 e77222a4 2006-05-04 devnull 	if(i > d){
 93 e77222a4 2006-05-04 devnull 		werrstr("bad address %d > %d (%x %x)", i, d, e->type, e->flags);
 94 e77222a4 2006-05-04 devnull 		return nil;
 95 e77222a4 2006-05-04 devnull 	}
 96 e77222a4 2006-05-04 devnull 
 97 e77222a4 2006-05-04 devnull /*fprint(2, "vtread %V\n", e->score); */
 98 75d04888 2009-05-25 rsc 	b = vtcacheglobal(c, e->score, e->type, d == 0 ? e->dsize : e->psize);
 99 e77222a4 2006-05-04 devnull 	for(i=d-1; i>=0 && b; i--){
100 e77222a4 2006-05-04 devnull 		t = VtDataType+i;
101 e77222a4 2006-05-04 devnull /*fprint(2, "vtread %V\n", b->data+index[i]*VtScoreSize); */
102 e77222a4 2006-05-04 devnull 		memmove(score, b->data+index[i]*VtScoreSize, VtScoreSize);
103 e77222a4 2006-05-04 devnull 		vtblockput(b);
104 75d04888 2009-05-25 rsc 		b = vtcacheglobal(c, score, t, i == 0 ? e->dsize : e->psize);
105 e77222a4 2006-05-04 devnull 	}
106 e77222a4 2006-05-04 devnull 	return b;
107 e77222a4 2006-05-04 devnull }
108 e77222a4 2006-05-04 devnull 
109 0c98da8b 2005-07-13 devnull static void
110 0c98da8b 2005-07-13 devnull diskventiclose(Disk *dd)
111 0c98da8b 2005-07-13 devnull {
112 0c98da8b 2005-07-13 devnull 	DiskVenti *d = (DiskVenti*)dd;
113 0c98da8b 2005-07-13 devnull 	free(d);
114 0c98da8b 2005-07-13 devnull }
115 0c98da8b 2005-07-13 devnull 
116 0c98da8b 2005-07-13 devnull Disk*
117 0c98da8b 2005-07-13 devnull diskopenventi(VtCache *c, uchar score[VtScoreSize])
118 0c98da8b 2005-07-13 devnull {
119 0c98da8b 2005-07-13 devnull 	DiskVenti *d;
120 0c98da8b 2005-07-13 devnull 	VtEntry e;
121 0c98da8b 2005-07-13 devnull 	VtRoot root;
122 0c98da8b 2005-07-13 devnull 	VtBlock *b;
123 0c98da8b 2005-07-13 devnull 
124 75d04888 2009-05-25 rsc 	if((b = vtcacheglobal(c, score, VtRootType, VtRootSize)) == nil)
125 0c98da8b 2005-07-13 devnull 		goto Err;
126 0c98da8b 2005-07-13 devnull 	if(vtrootunpack(&root, b->data) < 0)
127 0c98da8b 2005-07-13 devnull 		goto Err;
128 0c98da8b 2005-07-13 devnull 	if(root.blocksize < 512 || (root.blocksize&(root.blocksize-1))){
129 0c98da8b 2005-07-13 devnull 		werrstr("bad blocksize %d", root.blocksize);
130 0c98da8b 2005-07-13 devnull 		goto Err;
131 0c98da8b 2005-07-13 devnull 	}
132 0c98da8b 2005-07-13 devnull 	vtblockput(b);
133 0c98da8b 2005-07-13 devnull 
134 75d04888 2009-05-25 rsc 	if((b = vtcacheglobal(c, root.score, VtDirType, VtEntrySize)) == nil)
135 0c98da8b 2005-07-13 devnull 		goto Err;
136 0c98da8b 2005-07-13 devnull 	if(vtentryunpack(&e, b->data, 0) < 0)
137 0c98da8b 2005-07-13 devnull 		goto Err;
138 0c98da8b 2005-07-13 devnull 	vtblockput(b);
139 0c98da8b 2005-07-13 devnull 	b = nil;
140 0c98da8b 2005-07-13 devnull 	if((e.type&VtTypeBaseMask) != VtDataType){
141 0c98da8b 2005-07-13 devnull 		werrstr("not a single file");
142 0c98da8b 2005-07-13 devnull 		goto Err;
143 0c98da8b 2005-07-13 devnull 	}
144 0c98da8b 2005-07-13 devnull 
145 0c98da8b 2005-07-13 devnull 	d = mallocz(sizeof(DiskVenti), 1);
146 0c98da8b 2005-07-13 devnull 	if(d == nil)
147 0c98da8b 2005-07-13 devnull 		goto Err;
148 0c98da8b 2005-07-13 devnull 
149 0c98da8b 2005-07-13 devnull 	d->disk._read = diskventiread;
150 0c98da8b 2005-07-13 devnull 	d->disk._close = diskventiclose;
151 0c98da8b 2005-07-13 devnull 	d->e = e;
152 0c98da8b 2005-07-13 devnull 	d->c = c;
153 0c98da8b 2005-07-13 devnull 	return &d->disk;
154 0c98da8b 2005-07-13 devnull 
155 0c98da8b 2005-07-13 devnull Err:
156 0c98da8b 2005-07-13 devnull 	if(b)
157 0c98da8b 2005-07-13 devnull 		vtblockput(b);
158 6519f895 2007-11-05 rsc 
159 6519f895 2007-11-05 rsc 	_nfilereads_darwin_sucks();  /* force Darwin ld to pull in file.o */
160 0c98da8b 2005-07-13 devnull 	return nil;
161 0c98da8b 2005-07-13 devnull }