123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174 |
- #include "all.h"
- enum{
- MAXWREN = 7,
- };
- #define WMAGIC "kfs wren device\n"
- typedef struct Wren Wren;
- struct Wren{
- QLock;
- Device dev;
- uvlong size;
- int fd;
- };
- static Wren *wrens;
- static int maxwren;
- char *wrenfile;
- int nwren;
- int badmagic;
- static Wren *
- wren(Device dev)
- {
- int i;
- for(i = 0; i < maxwren; i++)
- if(devcmp(dev, wrens[i].dev) == 0)
- return &wrens[i];
- panic("can't find wren for %D", dev);
- return 0;
- }
- void
- wreninit(Device dev)
- {
- char buf[MAXBUFSIZE];
- Wren *w;
- Dir *d;
- int fd, i;
- if(wrens == 0)
- wrens = ialloc(MAXWREN * sizeof *wrens);
- w = &wrens[maxwren];
- fd = open(wrenfile, ORDWR);
- if(fd < 0)
- panic("can't open %s", wrenfile);
- if((d = dirfstat(fd)) == nil)
- panic("can't stat %s\n", wrenfile);
- seek(fd, 0, 0);
- i = read(fd, buf, sizeof buf);
- if(i < sizeof buf)
- panic("can't read %s", wrenfile);
- badmagic = 0;
- RBUFSIZE = 1024;
- if(strncmp(buf+256, WMAGIC, strlen(WMAGIC)) == 0){
- RBUFSIZE = atol(buf+256+strlen(WMAGIC));
- if(RBUFSIZE % 512){
- fprint(2, "kfs: bad buffersize(%d): assuming 1k blocks\n", RBUFSIZE);
- RBUFSIZE = 1024;
- }
- }else
- badmagic = 1;
- w->dev = dev;
- w->size = d->length;
- free(d);
- w->fd = fd;
- maxwren++;
- }
- void
- wrenream(Device dev)
- {
- Wren *w;
- char buf[MAXBUFSIZE];
- int fd, i;
- if(RBUFSIZE % 512)
- panic("kfs: bad buffersize(%d): restart a multiple of 512\n", RBUFSIZE);
- if(RBUFSIZE > sizeof(buf))
- panic("kfs: bad buffersize(%d): must be at most %d\n", RBUFSIZE, sizeof(buf));
- print("kfs: reaming the file system using %d byte blocks\n", RBUFSIZE);
- w = wren(dev);
- fd = w->fd;
- memset(buf, 0, sizeof buf);
- sprint(buf+256, "%s%d\n", WMAGIC, RBUFSIZE);
- qlock(w);
- i = seek(fd, 0, 0) < 0 || write(fd, buf, RBUFSIZE) != RBUFSIZE;
- qunlock(w);
- if(i < 0)
- panic("can't ream disk");
- }
- int
- wrentag(char *p, int tag, long qpath)
- {
- Tag *t;
- t = (Tag*)(p+BUFSIZE);
- return t->tag != tag || (qpath&~QPDIR) != t->path;
- }
- int
- wrencheck(Device dev)
- {
- char buf[MAXBUFSIZE];
- if(badmagic)
- return 1;
- if(RBUFSIZE > sizeof(buf))
- panic("kfs: bad buffersize(%d): must be at most %d\n", RBUFSIZE, sizeof(buf));
- if(wrenread(dev, wrensuper(dev), buf) || wrentag(buf, Tsuper, QPSUPER)
- || wrenread(dev, wrenroot(dev), buf) || wrentag(buf, Tdir, QPROOT))
- return 1;
- if(((Dentry *)buf)[0].mode & DALLOC)
- return 0;
- return 1;
- }
- long
- wrensize(Device dev)
- {
- return wren(dev)->size / RBUFSIZE;
- }
- long
- wrensuper(Device dev)
- {
- USED(dev);
- return 1;
- }
- long
- wrenroot(Device dev)
- {
- USED(dev);
- return 2;
- }
- int
- wrenread(Device dev, long addr, void *b)
- {
- Wren *w;
- int fd, i;
- w = wren(dev);
- fd = w->fd;
- qlock(w);
- i = seek(fd, (vlong)addr*RBUFSIZE, 0) == -1 || read(fd, b, RBUFSIZE) != RBUFSIZE;
- qunlock(w);
- if(i)
- print("wrenread failed: %r\n");
- return i;
- }
- int
- wrenwrite(Device dev, long addr, void *b)
- {
- Wren *w;
- int fd, i;
- w = wren(dev);
- fd = w->fd;
- qlock(w);
- i = seek(fd, (vlong)addr*RBUFSIZE, 0) == -1 || write(fd, b, RBUFSIZE) != RBUFSIZE;
- qunlock(w);
- if(i)
- print("wrenwrite failed: %r\n");
- return i;
- }
|