1 /*
2  * Copyright (c) 2015 Dmitry V. Levin <ldv@altlinux.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. The name of the author may not be used to endorse or promote products
14  *    derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include "defs.h"
29 
30 enum {
31 	IOPRIO_WHO_PROCESS = 1,
32 	IOPRIO_WHO_PGRP,
33 	IOPRIO_WHO_USER
34 };
35 
36 #include "xlat/ioprio_who.h"
37 
38 enum {
39 	IOPRIO_CLASS_NONE,
40 	IOPRIO_CLASS_RT,
41 	IOPRIO_CLASS_BE,
42 	IOPRIO_CLASS_IDLE
43 };
44 
45 #include "xlat/ioprio_class.h"
46 
47 #define IOPRIO_CLASS_SHIFT	(13)
48 #define IOPRIO_PRIO_MASK	((1ul << IOPRIO_CLASS_SHIFT) - 1)
49 
50 #define IOPRIO_PRIO_CLASS(mask)	((mask) >> IOPRIO_CLASS_SHIFT)
51 #define IOPRIO_PRIO_DATA(mask)	((mask) & IOPRIO_PRIO_MASK)
52 
53 static const char *
sprint_ioprio(int ioprio)54 sprint_ioprio(int ioprio)
55 {
56 	static char outstr[256];
57 	const char *str;
58 	int class, data;
59 
60 	class = IOPRIO_PRIO_CLASS(ioprio);
61 	data = IOPRIO_PRIO_DATA(ioprio);
62 	str = xlookup(ioprio_class, class);
63 	if (str)
64 		sprintf(outstr, "IOPRIO_PRIO_VALUE(%s,%d)", str, data);
65 	else
66 		sprintf(outstr, "IOPRIO_PRIO_VALUE(%#x /* %s */,%d)",
67 			class, "IOPRIO_CLASS_???", data);
68 
69 	return outstr;
70 }
71 
SYS_FUNC(ioprio_get)72 SYS_FUNC(ioprio_get)
73 {
74 	if (entering(tcp)) {
75 		/* int which */
76 		printxval(ioprio_who, tcp->u_arg[0], "IOPRIO_WHO_???");
77 		/* int who */
78 		tprintf(", %d", (int) tcp->u_arg[1]);
79 		return 0;
80 	} else {
81 		if (syserror(tcp))
82 			return 0;
83 
84 		tcp->auxstr = sprint_ioprio(tcp->u_rval);
85 		return RVAL_STR;
86 	}
87 }
88 
SYS_FUNC(ioprio_set)89 SYS_FUNC(ioprio_set)
90 {
91 	/* int which */
92 	printxval(ioprio_who, tcp->u_arg[0], "IOPRIO_WHO_???");
93 	/* int who */
94 	tprintf(", %d, ", (int) tcp->u_arg[1]);
95 	/* int ioprio */
96 	tprints(sprint_ioprio(tcp->u_arg[2]));
97 
98 	return RVAL_DECODED;
99 }
100