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#include <stdio.h>
#include <string.h>
#include "umdev.h"
#include "stdlib.h"
#include <errno.h>
#include <linux/fs.h>
#include <linux/hdreg.h>
#include <config.h>
#define STD_SIZE 64*1024
#define STD_SECTORSIZE 512
#define READONLY 1
#define MBR 2
struct ramdisk {
char *diskdata;
char flags;
unsigned long long rd_size;
struct hd_geometry rd_geom;
};
static int rd_open(char type, dev_t device, struct dev_info *di)
{
return 0;
}
static int rd_read(char type, dev_t device, char *buf, size_t len, loff_t pos, struct dev_info *di)
{
struct ramdisk *ramdisk = umdev_getprivatedata(di->devhandle);
if (ramdisk) {
loff_t size=ramdisk->rd_size*STD_SECTORSIZE;
size_t rlen;
if (pos > size) pos=size;
if (pos+len <= size)
rlen=len;
else
rlen=size-pos;
memcpy(buf,ramdisk->diskdata+pos,rlen);
return rlen;
}
else
return -ENODEV;
}
static int rd_write(char type, dev_t device, const char *buf, size_t len, loff_t pos, struct dev_info *di)
{
struct ramdisk *ramdisk = umdev_getprivatedata(di->devhandle);
if (ramdisk) {
if (ramdisk->flags & READONLY)
return -EACCES;
else {
loff_t size=ramdisk->rd_size*STD_SECTORSIZE;
size_t rlen;
if (pos > size) pos=size;
if (pos+len <= size)
rlen=len;
else
rlen=size-pos;
memcpy(ramdisk->diskdata+pos,buf,rlen);
return rlen;
}
}
else
return -ENODEV;
}
static int rd_release(char type, dev_t device, struct dev_info *di)
{
return 0;
}
static loff_t rd_lseek(char type, dev_t device, loff_t offset, int whence, loff_t pos, struct dev_info *di)
{
struct ramdisk *ramdisk = umdev_getprivatedata(di->devhandle);
if (ramdisk) {
loff_t size=ramdisk->rd_size*STD_SECTORSIZE;
loff_t rv;
switch (whence) {
case SEEK_SET:
rv=offset;
break;
case SEEK_CUR:
rv=pos+offset;
break;
case SEEK_END:
rv=size+offset;
break;
}
if (rv<0) rv=0;
if (rv>size) rv=size;
return rv;
}
else
return -ENODEV;
}
static void rd_setmbr(char *s,struct ramdisk *rd)
{
rd->flags |= MBR;
}
static void rd_setsize(char *s,struct ramdisk *rd)
{
if (s) {
int len=strlen(s);
long long size=atoi(s);
switch (s[len-1]) {
case 'k':
case 'K': size *= 1024 / STD_SECTORSIZE; break;
case 'm':
case 'M': size *= 1024 * 1024 / STD_SECTORSIZE; break;
case 'g':
case 'G': size *= 1024 * 1024 * 1024 / STD_SECTORSIZE; break;
}
rd->rd_size=size;
}
}
static struct devargitem umdevargtab[] = {
{"size=", rd_setsize},
{"mbr", rd_setmbr},
};
#define UMDEVARGTABSIZE sizeof(umdevargtab)/sizeof(struct devargitem)
static int rd_init(char type, dev_t device, char *path, unsigned long flags, char *args,struct umdev *devhandle)
{
struct ramdisk *ramdisk=calloc(1,sizeof (struct ramdisk));
if(args)
devargs(args, umdevargtab, UMDEVARGTABSIZE, ramdisk);
if (ramdisk) {
if (ramdisk->rd_size == 0)
ramdisk->rd_size=STD_SIZE;
ramdisk->rd_geom.start=0;
if (ramdisk->rd_size == (unsigned int) ramdisk->rd_size) {
ramdisk->rd_geom.heads=16;
ramdisk->rd_geom.sectors=16;
ramdisk->rd_geom.cylinders=(ramdisk->rd_size+(ramdisk->rd_geom.heads*ramdisk->rd_geom.sectors)-1)/(ramdisk->rd_geom.heads*ramdisk->rd_geom.sectors);
} else {
ramdisk->rd_geom.heads=128;
ramdisk->rd_geom.sectors=128;
ramdisk->rd_geom.cylinders=(ramdisk->rd_size+(ramdisk->rd_geom.heads*ramdisk->rd_geom.sectors)-1)/(ramdisk->rd_geom.heads*ramdisk->rd_geom.sectors);
}
ramdisk->rd_size=ramdisk->rd_geom.heads*ramdisk->rd_geom.sectors*ramdisk->rd_geom.cylinders;
if (!ramdisk->diskdata) {
ramdisk->diskdata=malloc(ramdisk->rd_size * STD_SECTORSIZE);
if (!ramdisk->diskdata) {
free(ramdisk);
return -ENOMEM;
}
}
mode_t mode=umdev_getmode(devhandle);
mode = (mode & ~S_IFMT) | S_IFBLK;
umdev_setmode(devhandle, mode);
umdev_setprivatedata(devhandle,ramdisk);
return 0;
} else
return -ENODEV;
}
static int rd_fini(char type, dev_t device, struct umdev *devhandle)
{
struct ramdisk *ramdisk = umdev_getprivatedata(devhandle);
if (ramdisk) {
free(ramdisk->diskdata);
free(ramdisk);
}
return 0;
}
static int rd_ioctl(char type, dev_t device, int req, void * arg, struct dev_info *di)
{
struct ramdisk *ramdisk = umdev_getprivatedata(di->devhandle);
if (ramdisk) {
switch (req) {
case BLKROSET: if (*(int *)arg != 0)
ramdisk->flags |= READONLY;
break;
case BLKROGET: *(int *)arg = ((ramdisk->flags & READONLY) != 0);
break;
case BLKSSZGET: *(int *)arg = STD_SECTORSIZE;
break;
case BLKRRPART: break;
case BLKGETSIZE: *(int *)arg = ramdisk->rd_size *
((ramdisk->flags & MBR)?1:STD_SECTORSIZE);
break;
case BLKGETSIZE64: *(long long *)arg = ramdisk->rd_size * STD_SECTORSIZE;
//printk("BLKGETSIZE64 %lld\n",*(long long *)arg);
break;
case HDIO_GETGEO: {
struct hd_geometry *hdg = arg;
*hdg=ramdisk->rd_geom;
}
break;
default: return -EINVAL;
}
return 0;
} else
return -ENODEV;
}
static int rd_ioctl_params(char type, dev_t device, int req, struct dev_info *di)
{
switch (req) {
case BLKROSET: return (sizeof(int) | IOCTL_R);
case BLKROGET: return (sizeof(int) | IOCTL_W);
case BLKSSZGET: return (sizeof(int) | IOCTL_W);
case BLKRRPART: return 0;
case BLKGETSIZE: return (sizeof(int) | IOCTL_W);
case BLKGETSIZE64: return (sizeof(long long) | IOCTL_W);
case HDIO_GETGEO: return (sizeof(struct hd_geometry) | IOCTL_W);
default: return 0;
}
}
struct umdev_operations umdev_ops={
.open=rd_open,
.read=rd_read,
.write=rd_write,
.release=rd_release,
.lseek=rd_lseek,
.init=rd_init,
.ioctl=rd_ioctl,
.ioctlparms=rd_ioctl_params,
.fini=rd_fini,
};
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