Subversion Repositories planix.SVN

#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;
}