Archipelago » qemu

/* User memory access */

#include <stdio.h>

#include <string.h>

#include "qemu.h"

/* copy_from_user() and copy_to_user() are usually used to copy data

 * buffers between the target and host.  These internally perform

 * locking/unlocking of the memory.

 */

abi_long copy_from_user(void *hptr, abi_ulong gaddr, size_t len)

{

    abi_long ret = 0;

    void *ghptr;

    if ((ghptr = lock_user(VERIFY_READ, gaddr, len, 1))) {

        memcpy(hptr, ghptr, len);

        unlock_user(ghptr, gaddr, 0);

    } else

        ret = -TARGET_EFAULT;

    return ret;

}

abi_long copy_to_user(abi_ulong gaddr, void *hptr, size_t len)

{

    abi_long ret = 0;

    void *ghptr;

    if ((ghptr = lock_user(VERIFY_WRITE, gaddr, len, 0))) {

        memcpy(ghptr, hptr, len);

        unlock_user(ghptr, gaddr, len);

    } else

        ret = -TARGET_EFAULT;

    return ret;

}

/* Return the length of a string in target memory.  */

/* FIXME - this doesn't check access_ok() - it's rather complicated to

 * do it correctly because we need to check the bytes in a page and then

 * skip to the next page and check the bytes there until we find the

 * terminator.  There should be a general function to do this that

 * can look for any byte terminator in a buffer - not strlen().

 */

abi_long target_strlen(abi_ulong gaddr)

{

    return strlen(g2h(gaddr));

}