4 /* This is minimal version of Linux' linux/ioprio.h header file, which
8 #include <sys/syscall.h>
11 * Gives us 8 prio classes with 13-bits of data for each class
13 #define IOPRIO_BITS (16)
14 #define IOPRIO_CLASS_SHIFT (13)
15 #define IOPRIO_PRIO_MASK ((1UL << IOPRIO_CLASS_SHIFT) - 1)
17 #define IOPRIO_PRIO_CLASS(mask) ((mask) >> IOPRIO_CLASS_SHIFT)
18 #define IOPRIO_PRIO_DATA(mask) ((mask) & IOPRIO_PRIO_MASK)
19 #define IOPRIO_PRIO_VALUE(class, data) (((class) << IOPRIO_CLASS_SHIFT) | data)
21 #define ioprio_valid(mask) (IOPRIO_PRIO_CLASS((mask)) != IOPRIO_CLASS_NONE)
24 * These are the io priority groups as implemented by CFQ. RT is the realtime
25 * class, it always gets premium service. BE is the best-effort scheduling
26 * class, the default for any process. IDLE is the idle scheduling class, it
27 * is only served when no one else is using the disk.
37 * 8 best effort priority levels are supported
39 #define IOPRIO_BE_NR (8)
42 IOPRIO_WHO_PROCESS = 1,
47 static inline int ioprio_set(int which, int who, int ioprio) {
48 return syscall(__NR_ioprio_set, which, who, ioprio);
51 static inline int ioprio_get(int which, int who) {
52 return syscall(__NR_ioprio_get, which, who);