DragonFly On-Line Manual Pages

COPY(9)               DragonFly Kernel Developer's Manual              COPY(9)

NAME
     copy, copyin, copyin_nofault, copyout, copyout_nofault, copystr,
     copyinstr -- kernel copy functions

SYNOPSIS
     #include <sys/types.h>
     #include <sys/systm.h>

     int
     copyin(const void *uaddr, void *kaddr, size_t len);

     int
     copyin_nofault(const void *uaddr, void *kaddr, size_t len);

     int
     copyout(const void *kaddr, void *uaddr, size_t len);

     int
     copyout_nofault(const void *kaddr, void *uaddr, size_t len);

     int
     copystr(const void *kfaddr, void *kdaddr, size_t len, size_t *done);

     int
     copyinstr(const void *uaddr, void *kaddr, size_t len, size_t *done);

DESCRIPTION
     The copy functions are designed to copy contiguous data from one address
     to another.  All but copystr() copy data from user-space to kernel-space
     or vice-versa.

     The copyin() and copyin_nofault() functions copy len bytes of data from
     the user-space address uaddr to the kernel-space address kaddr.

     The copyout() and copyout_nofault() functions copy len bytes of data from
     the kernel-space address kaddr to the user-space address uaddr.

     The copyin_nofault() and copyout_nofault() functions require that the
     kernel-space and user-space data be accessible without incurring a page
     fault.  The source and destination addresses must be physically mapped
     for read and write access, respectively, and neither the source nor des-
     tination addresses may be pageable.

     The copystr() function copies a NUL-terminated string, at most len bytes
     long, from kernel-space address kfaddr to kernel-space address kdaddr.
     The number of bytes actually copied, including the terminating NUL, is
     returned in *done (if done is non-NULL).

     The copyinstr() function copies a NUL-terminated string, at most len
     bytes long, from user-space address uaddr to kernel-space address kaddr.
     The number of bytes actually copied, including the terminating NUL, is
     returned in *done (if done is non-NULL).

RETURN VALUES
     The copy functions return 0 on success or EFAULT if a bad address is
     encountered.  In addition, the copyin_nofault() and copyout_nofault()
     functions return EFAULT if a page fault occurs, and the copystr() and
     copyinstr() functions return ENAMETOOLONG if the string is longer than
     len bytes.

SEE ALSO
     fetch(9), store(9)

DragonFly 3.5                    July 9, 2011                    DragonFly 3.5