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>
6 0c98da8b 2005-07-13 devnull extern void vtlibthread(void);
8 0c98da8b 2005-07-13 devnull typedef struct DiskVenti DiskVenti;
9 0c98da8b 2005-07-13 devnull struct DiskVenti
11 0c98da8b 2005-07-13 devnull Disk disk;
12 0c98da8b 2005-07-13 devnull VtEntry e;
13 0c98da8b 2005-07-13 devnull VtCache *c;
16 d3285dcb 2005-12-16 devnull extern int nfilereads;
19 0c98da8b 2005-07-13 devnull * This part is like file.c but doesn't require storing the root block
20 0c98da8b 2005-07-13 devnull * in the cache permanently and doesn't care about locking since
21 0c98da8b 2005-07-13 devnull * all the blocks are read-only. Perhaps at some point this functionality
22 0c98da8b 2005-07-13 devnull * should go into libvac in some form.
24 0c98da8b 2005-07-13 devnull static int
25 0c98da8b 2005-07-13 devnull vtfileindices(VtEntry *e, u32int bn, int *index)
27 0c98da8b 2005-07-13 devnull int i, np;
29 0c98da8b 2005-07-13 devnull memset(index, 0, VtPointerDepth*sizeof(int));
31 0c98da8b 2005-07-13 devnull np = e->psize/VtScoreSize;
32 0c98da8b 2005-07-13 devnull memset(index, 0, sizeof(index));
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;
38 0c98da8b 2005-07-13 devnull index[i] = bn % np;
39 0c98da8b 2005-07-13 devnull bn /= np;
41 0c98da8b 2005-07-13 devnull return i;
44 0c98da8b 2005-07-13 devnull static VtBlock*
45 0c98da8b 2005-07-13 devnull _vtfileblock(VtCache *c, VtEntry *e, u32int bn)
47 0c98da8b 2005-07-13 devnull VtBlock *b, *bb;
48 0c98da8b 2005-07-13 devnull int i, d, index[VtPointerDepth+1], t;
50 0c98da8b 2005-07-13 devnull i = vtfileindices(e, bn, index);
51 0c98da8b 2005-07-13 devnull if(i < 0)
52 0c98da8b 2005-07-13 devnull return nil;
53 0c98da8b 2005-07-13 devnull d = (e->type&VtTypeDepthMask);
54 0c98da8b 2005-07-13 devnull if(i > d){
55 0c98da8b 2005-07-13 devnull werrstr("bad address %d > %d (%x %x)", i, d, e->type, e->flags);
56 0c98da8b 2005-07-13 devnull return nil;
59 0c98da8b 2005-07-13 devnull //fprint(2, "vtread %V\n", e->score);
60 0c98da8b 2005-07-13 devnull b = vtcacheglobal(c, e->score, e->type);
61 0c98da8b 2005-07-13 devnull if(b == nil)
62 0c98da8b 2005-07-13 devnull return nil;
64 0c98da8b 2005-07-13 devnull for(i=d-1; i>=0; i--){
65 0c98da8b 2005-07-13 devnull t = VtDataType+i;
66 0c98da8b 2005-07-13 devnull //fprint(2, "vtread %V\n", b->data+index[i]*VtScoreSize);
67 0c98da8b 2005-07-13 devnull bb = vtcacheglobal(c, b->data+index[i]*VtScoreSize, t);
68 0c98da8b 2005-07-13 devnull vtblockput(b);
69 0c98da8b 2005-07-13 devnull if(bb == nil)
70 0c98da8b 2005-07-13 devnull return nil;
73 0c98da8b 2005-07-13 devnull return b;
76 0c98da8b 2005-07-13 devnull static void
77 0c98da8b 2005-07-13 devnull diskventiblockput(Block *b)
79 0c98da8b 2005-07-13 devnull vtblockput(b->priv);
83 0c98da8b 2005-07-13 devnull static Block*
84 0c98da8b 2005-07-13 devnull diskventiread(Disk *dd, u32int len, u64int offset)
86 0c98da8b 2005-07-13 devnull DiskVenti *d = (DiskVenti*)dd;
87 0c98da8b 2005-07-13 devnull VtBlock *vb;
88 0c98da8b 2005-07-13 devnull Block *b;
89 0c98da8b 2005-07-13 devnull int frag;
91 0c98da8b 2005-07-13 devnull nfilereads++;
92 0c98da8b 2005-07-13 devnull vb = _vtfileblock(d->c, &d->e, offset/d->e.dsize);
93 0c98da8b 2005-07-13 devnull if(vb == nil)
94 0c98da8b 2005-07-13 devnull return nil;
96 0c98da8b 2005-07-13 devnull b = mallocz(sizeof(Block), 1);
97 0c98da8b 2005-07-13 devnull if(b == nil){
98 0c98da8b 2005-07-13 devnull vtblockput(vb);
99 0c98da8b 2005-07-13 devnull return nil;
102 0c98da8b 2005-07-13 devnull b->priv = vb;
103 0c98da8b 2005-07-13 devnull b->_close = diskventiblockput;
104 0c98da8b 2005-07-13 devnull frag = offset%d->e.dsize;
105 0c98da8b 2005-07-13 devnull b->data = (uchar*)vb->data + frag;
106 0c98da8b 2005-07-13 devnull b->len = d->e.dsize - frag;
107 0c98da8b 2005-07-13 devnull if(b->len > len)
108 0c98da8b 2005-07-13 devnull b->len = len;
109 0c98da8b 2005-07-13 devnull return b;
112 0c98da8b 2005-07-13 devnull static void
113 0c98da8b 2005-07-13 devnull diskventiclose(Disk *dd)
115 0c98da8b 2005-07-13 devnull DiskVenti *d = (DiskVenti*)dd;
116 0c98da8b 2005-07-13 devnull free(d);
120 0c98da8b 2005-07-13 devnull diskopenventi(VtCache *c, uchar score[VtScoreSize])
122 0c98da8b 2005-07-13 devnull DiskVenti *d;
123 0c98da8b 2005-07-13 devnull VtEntry e;
124 0c98da8b 2005-07-13 devnull VtRoot root;
125 0c98da8b 2005-07-13 devnull VtBlock *b;
127 0c98da8b 2005-07-13 devnull if((b = vtcacheglobal(c, score, VtRootType)) == nil)
128 0c98da8b 2005-07-13 devnull goto Err;
129 0c98da8b 2005-07-13 devnull if(vtrootunpack(&root, b->data) < 0)
130 0c98da8b 2005-07-13 devnull goto Err;
131 0c98da8b 2005-07-13 devnull if(root.blocksize < 512 || (root.blocksize&(root.blocksize-1))){
132 0c98da8b 2005-07-13 devnull werrstr("bad blocksize %d", root.blocksize);
133 0c98da8b 2005-07-13 devnull goto Err;
135 0c98da8b 2005-07-13 devnull vtblockput(b);
137 0c98da8b 2005-07-13 devnull if((b = vtcacheglobal(c, root.score, VtDirType)) == nil)
138 0c98da8b 2005-07-13 devnull goto Err;
139 0c98da8b 2005-07-13 devnull if(vtentryunpack(&e, b->data, 0) < 0)
140 0c98da8b 2005-07-13 devnull goto Err;
141 0c98da8b 2005-07-13 devnull vtblockput(b);
142 0c98da8b 2005-07-13 devnull b = nil;
143 0c98da8b 2005-07-13 devnull if((e.type&VtTypeBaseMask) != VtDataType){
144 0c98da8b 2005-07-13 devnull werrstr("not a single file");
145 0c98da8b 2005-07-13 devnull goto Err;
148 0c98da8b 2005-07-13 devnull d = mallocz(sizeof(DiskVenti), 1);
149 0c98da8b 2005-07-13 devnull if(d == nil)
150 0c98da8b 2005-07-13 devnull goto Err;
152 0c98da8b 2005-07-13 devnull d->disk._read = diskventiread;
153 0c98da8b 2005-07-13 devnull d->disk._close = diskventiclose;
154 0c98da8b 2005-07-13 devnull d->e = e;
155 0c98da8b 2005-07-13 devnull d->c = c;
156 0c98da8b 2005-07-13 devnull return &d->disk;
160 0c98da8b 2005-07-13 devnull vtblockput(b);
161 0c98da8b 2005-07-13 devnull return nil;
