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#include <u.h>
#include <libc.h>
#include <auth.h>
#include <fcall.h>
#include <thread.h>
#include <9p.h>
#include "flashfs.h"
static char* file;
static int fd;
static uchar *ones;
static int isdev;
struct {
int dfd; /* data */
int cfd; /* control */
} flash;
void
initdata(char *f, int)
{
char err[ERRMAX];
char buf[1024], *fld[8];
int n;
Dir *d;
isdev = 1;
flash.dfd = open(f, ORDWR);
if(flash.dfd < 0){
errstr(err, sizeof err);
if((flash.dfd = create(f, ORDWR, 0666)) >= 0){
fprint(2, "warning: created plain file %s\n", buf);
goto Plain;
}
errstr(err, sizeof err); /* restore open error */
sysfatal("opening %s: %r", f);
}
if(snprint(buf, sizeof buf, "%sctl", f) != strlen(f)+3)
sysfatal("path too long: %s", f);
flash.cfd = open(buf, ORDWR);
if(flash.cfd < 0){
fprint(2, "warning: cannot open %s (%r); assuming plain file\n", buf);
Plain:
isdev = 0;
if(sectsize == 0)
sectsize = 512;
if(nsects == 0){
if((d = dirstat(f)) == nil)
sysfatal("stat %s: %r", f);
nsects = d->length / sectsize;
free(d);
}
ones = emalloc9p(sectsize);
memset(ones, ~0, sectsize);
}else{
n = read(flash.cfd, buf, sizeof(buf)-1);
if(n <= 0)
sysfatal("reading %sctl: %r", f);
buf[n] = 0;
n = tokenize(buf, fld, nelem(fld));
if(n < 7)
sysfatal("bad flash geometry");
nsects = atoi(fld[5]);
sectsize = atoi(fld[6]);
if(nsects < 8)
sysfatal("unreasonable value for nsects: %lud", nsects);
if(sectsize < 512)
sysfatal("unreasonable value for sectsize: %lud", sectsize);
}
}
void
clearsect(int sect)
{
if(isdev==0){
if(pwrite(flash.dfd, ones, sectsize, sect*sectsize) != sectsize)
sysfatal("couldn't erase sector %d: %r", sect);
}else{
if(fprint(flash.cfd, "erase %lud", sect * sectsize) < 0)
sysfatal("couldn't erase sector %d: %r", sect);
}
}
void
readdata(int sect, void *buff, ulong count, ulong off)
{
long n;
ulong m;
m = sect * sectsize + off;
n = pread(flash.dfd, buff, count, m);
if(n < 0)
sysfatal("error reading at %lux: %r", m);
if(n != count)
sysfatal("short read at %lux, %ld instead of %lud", m, n, count);
}
int
writedata(int err, int sect, void *buff, ulong count, ulong off)
{
long n;
ulong m;
m = sect*sectsize + off;
n = pwrite(flash.dfd, buff, count, m);
if(n < 0){
if(err)
return 0;
sysfatal("error writing at %lux: %r", m);
}
if(n != count){
if(err)
return 0;
sysfatal("short write at %lud, %ld instead of %lud", m, n, count);
}
return 1;
}
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