DragonFly On-Line Manual Pages

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

NAME
     fetch, fubyte, fuword32, fuwordadd32, fuword64, fuwordadd64 -- fetch data
     from user-space

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

     int
     fubyte(const uint8_t *base);

     int32_t
     fuword32(const uint32_t *base);

     uint32_t
     fuwordadd32(volatile uint32_t *p, uint32_t val);

     int64_t
     fuword64(const uint64_t *base);

     uint64_t
     fuwordadd64(volatile uint64_t *p, uint64_t val);

DESCRIPTION
     The fetch functions are designed to copy small amounts of data from user-
     space.

     The fetch routines provide the following functionality:

     fubyte()       Fetches a byte of data from the user-space address base.

     fuword32()     Fetches 32 bits of data from the user-space address base.

     fuwordadd32()  Fetches 32 bits of data from the user-space address p,
                    adds val, and stores the result back to the user-space
                    address p.

     fuword64()     Fetches 64 bits of data from the user-space address base.

     fuwordadd64()  Fetches 64 bits of data from the user-space address p,
                    adds val, and stores the result back to the user-space
                    address p.

RETURN VALUES
     The fetch functions return the data fetched or -1 on failure.

SEE ALSO
     copy(9), store(9)

DragonFly 5.3                  November 17, 2018                 DragonFly 5.3