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#include <mach/vm_param.h>
#include <machine/vm_param.h>
#include <vm/vm_kern.h>
#include <vm/vm_user.h>
#include <device/device_types.h>
#include <device/ds_routines.h>
#include <device/conf.h>
#include <device/ramdisk.h>
#include <kern/printf.h>
#include <string.h>
static struct ramdisk {
void *data;
vm_size_t size;
} ramdisk[RAMDISK_MAX];
static int ramdisk_num = 0;
/* Initial ramdisks are created from the boot scripts */
int ramdisk_create(vm_size_t size, const void *initdata, int *out_no)
{
struct ramdisk *rd = &ramdisk[ramdisk_num];
int err;
if(ramdisk_num >= RAMDISK_MAX)
return -1;
/* allocate the memory */
rd->size = round_page(size);
err = kmem_alloc(kernel_map, (vm_offset_t *) &rd->data, rd->size);
if(err != KERN_SUCCESS)
return err;
/* initialize */
if(initdata)
memcpy(rd->data, initdata, rd->size);
else
memset(rd->data, 0, rd->size);
/* report */
if(out_no) *out_no = ramdisk_num;
printf("%s%d: %lu bytes @%p\n", RAMDISK_NAME, ramdisk_num,
(unsigned long) rd->size, rd->data);
ramdisk_num++;
return KERN_SUCCESS;
}
/* On d_open() we just check whether the ramdisk exists */
int ramdisk_open(dev_t dev, int mode, io_req_t ior)
{
return (dev < ramdisk_num) ? D_SUCCESS : D_NO_SUCH_DEVICE;
}
/* d_getstat() is used to query the device characteristics */
int ramdisk_getstat(dev_t dev, dev_flavor_t flavor, dev_status_t status,
mach_msg_type_number_t *status_count)
{
switch(flavor) {
case DEV_GET_SIZE:
status[DEV_GET_SIZE_DEVICE_SIZE] = ramdisk[dev].size;
status[DEV_GET_SIZE_RECORD_SIZE] = RAMDISK_BLOCKSZ;
*status_count = DEV_GET_SIZE_COUNT;
return D_SUCCESS;
case DEV_GET_RECORDS:
status[DEV_GET_RECORDS_DEVICE_RECORDS]
= ramdisk[dev].size / RAMDISK_BLOCKSZ;
status[DEV_GET_RECORDS_RECORD_SIZE] = RAMDISK_BLOCKSZ;
*status_count = DEV_GET_RECORDS_COUNT;
return D_SUCCESS;
}
return D_INVALID_OPERATION;
}
/* TODO: implement freeramdisk with setstat() ? */
/* Check the given io request and compute a pointer to the ramdisk data and the
* amount to be handled. */
static int ramdisk_ioreq(int dev, io_req_t ior, void **data, int *amt)
{
vm_offset_t ofs = ior->io_recnum * RAMDISK_BLOCKSZ;
if(ofs >= ramdisk[dev].size)
return D_INVALID_RECNUM;
*data = (char*) ramdisk[dev].data + ofs;
*amt = ior->io_count;
if(ofs + *amt > ramdisk[dev].size)
*amt = ramdisk[dev].size - ofs;
return KERN_SUCCESS;
}
/* Copy data from a vm_map_copy by mapping it temporarily. */
static int mem_map_cpy(void *dst, vm_map_copy_t src, int amt)
{
vm_offset_t srcaddr;
int err;
err = vm_map_copyout(device_io_map, &srcaddr, src);
if (err != KERN_SUCCESS)
return err;
memcpy(dst, (void *) srcaddr, amt);
vm_deallocate(device_io_map, srcaddr, amt);
return KERN_SUCCESS;
}
int ramdisk_read(dev_t dev, io_req_t ior)
{
void *data;
int amt, err;
err = ramdisk_ioreq(dev, ior, &data, &amt);
if(err != KERN_SUCCESS)
return err;
err = device_read_alloc (ior, ior->io_count);
if (err != KERN_SUCCESS)
return err;
memcpy(ior->io_data, data, amt);
ior->io_residual = ior->io_count - amt;
return D_SUCCESS;
}
int ramdisk_write(dev_t dev, io_req_t ior)
{
void *data;
int amt, err;
err = ramdisk_ioreq(dev, ior, &data, &amt);
if(err != KERN_SUCCESS)
return err;
if (!(ior->io_op & IO_INBAND)) {
/* Out-of-band data is transmitted as a vm_map_copy */
err = mem_map_cpy(data, (vm_map_copy_t) ior->io_data, amt);
if(err != KERN_SUCCESS)
return err;
} else {
/* In-band data can be accessed directly */
memcpy(data, ior->io_data, amt);
}
ior->io_residual = ior->io_count - amt;
return D_SUCCESS;
}
vm_offset_t ramdisk_mmap(dev_t dev, vm_offset_t off, vm_prot_t prot)
{
if(dev >= ramdisk_num)
return -1;
if(off >= ramdisk[dev].size)
return -1;
return pmap_phys_to_frame(kvtophys((vm_offset_t) ramdisk[dev].data + off));
}
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