1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Hypervisor filesystem for Linux on s390.
4*4882a593Smuzhiyun * Set Partition-Resource Parameter interface.
5*4882a593Smuzhiyun *
6*4882a593Smuzhiyun * Copyright IBM Corp. 2013
7*4882a593Smuzhiyun * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
8*4882a593Smuzhiyun */
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun #include <linux/compat.h>
11*4882a593Smuzhiyun #include <linux/errno.h>
12*4882a593Smuzhiyun #include <linux/gfp.h>
13*4882a593Smuzhiyun #include <linux/string.h>
14*4882a593Smuzhiyun #include <linux/types.h>
15*4882a593Smuzhiyun #include <linux/uaccess.h>
16*4882a593Smuzhiyun #include <asm/diag.h>
17*4882a593Smuzhiyun #include <asm/sclp.h>
18*4882a593Smuzhiyun #include "hypfs.h"
19*4882a593Smuzhiyun
20*4882a593Smuzhiyun #define DIAG304_SET_WEIGHTS 0
21*4882a593Smuzhiyun #define DIAG304_QUERY_PRP 1
22*4882a593Smuzhiyun #define DIAG304_SET_CAPPING 2
23*4882a593Smuzhiyun
24*4882a593Smuzhiyun #define DIAG304_CMD_MAX 2
25*4882a593Smuzhiyun
__hypfs_sprp_diag304(void * data,unsigned long cmd)26*4882a593Smuzhiyun static inline unsigned long __hypfs_sprp_diag304(void *data, unsigned long cmd)
27*4882a593Smuzhiyun {
28*4882a593Smuzhiyun register unsigned long _data asm("2") = (unsigned long) data;
29*4882a593Smuzhiyun register unsigned long _rc asm("3");
30*4882a593Smuzhiyun register unsigned long _cmd asm("4") = cmd;
31*4882a593Smuzhiyun
32*4882a593Smuzhiyun asm volatile("diag %1,%2,0x304\n"
33*4882a593Smuzhiyun : "=d" (_rc) : "d" (_data), "d" (_cmd) : "memory");
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun return _rc;
36*4882a593Smuzhiyun }
37*4882a593Smuzhiyun
hypfs_sprp_diag304(void * data,unsigned long cmd)38*4882a593Smuzhiyun static unsigned long hypfs_sprp_diag304(void *data, unsigned long cmd)
39*4882a593Smuzhiyun {
40*4882a593Smuzhiyun diag_stat_inc(DIAG_STAT_X304);
41*4882a593Smuzhiyun return __hypfs_sprp_diag304(data, cmd);
42*4882a593Smuzhiyun }
43*4882a593Smuzhiyun
hypfs_sprp_free(const void * data)44*4882a593Smuzhiyun static void hypfs_sprp_free(const void *data)
45*4882a593Smuzhiyun {
46*4882a593Smuzhiyun free_page((unsigned long) data);
47*4882a593Smuzhiyun }
48*4882a593Smuzhiyun
hypfs_sprp_create(void ** data_ptr,void ** free_ptr,size_t * size)49*4882a593Smuzhiyun static int hypfs_sprp_create(void **data_ptr, void **free_ptr, size_t *size)
50*4882a593Smuzhiyun {
51*4882a593Smuzhiyun unsigned long rc;
52*4882a593Smuzhiyun void *data;
53*4882a593Smuzhiyun
54*4882a593Smuzhiyun data = (void *) get_zeroed_page(GFP_KERNEL);
55*4882a593Smuzhiyun if (!data)
56*4882a593Smuzhiyun return -ENOMEM;
57*4882a593Smuzhiyun rc = hypfs_sprp_diag304(data, DIAG304_QUERY_PRP);
58*4882a593Smuzhiyun if (rc != 1) {
59*4882a593Smuzhiyun *data_ptr = *free_ptr = NULL;
60*4882a593Smuzhiyun *size = 0;
61*4882a593Smuzhiyun free_page((unsigned long) data);
62*4882a593Smuzhiyun return -EIO;
63*4882a593Smuzhiyun }
64*4882a593Smuzhiyun *data_ptr = *free_ptr = data;
65*4882a593Smuzhiyun *size = PAGE_SIZE;
66*4882a593Smuzhiyun return 0;
67*4882a593Smuzhiyun }
68*4882a593Smuzhiyun
__hypfs_sprp_ioctl(void __user * user_area)69*4882a593Smuzhiyun static int __hypfs_sprp_ioctl(void __user *user_area)
70*4882a593Smuzhiyun {
71*4882a593Smuzhiyun struct hypfs_diag304 *diag304;
72*4882a593Smuzhiyun unsigned long cmd;
73*4882a593Smuzhiyun void __user *udata;
74*4882a593Smuzhiyun void *data;
75*4882a593Smuzhiyun int rc;
76*4882a593Smuzhiyun
77*4882a593Smuzhiyun rc = -ENOMEM;
78*4882a593Smuzhiyun data = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
79*4882a593Smuzhiyun diag304 = kzalloc(sizeof(*diag304), GFP_KERNEL);
80*4882a593Smuzhiyun if (!data || !diag304)
81*4882a593Smuzhiyun goto out;
82*4882a593Smuzhiyun
83*4882a593Smuzhiyun rc = -EFAULT;
84*4882a593Smuzhiyun if (copy_from_user(diag304, user_area, sizeof(*diag304)))
85*4882a593Smuzhiyun goto out;
86*4882a593Smuzhiyun rc = -EINVAL;
87*4882a593Smuzhiyun if ((diag304->args[0] >> 8) != 0 || diag304->args[1] > DIAG304_CMD_MAX)
88*4882a593Smuzhiyun goto out;
89*4882a593Smuzhiyun
90*4882a593Smuzhiyun rc = -EFAULT;
91*4882a593Smuzhiyun udata = (void __user *)(unsigned long) diag304->data;
92*4882a593Smuzhiyun if (diag304->args[1] == DIAG304_SET_WEIGHTS ||
93*4882a593Smuzhiyun diag304->args[1] == DIAG304_SET_CAPPING)
94*4882a593Smuzhiyun if (copy_from_user(data, udata, PAGE_SIZE))
95*4882a593Smuzhiyun goto out;
96*4882a593Smuzhiyun
97*4882a593Smuzhiyun cmd = *(unsigned long *) &diag304->args[0];
98*4882a593Smuzhiyun diag304->rc = hypfs_sprp_diag304(data, cmd);
99*4882a593Smuzhiyun
100*4882a593Smuzhiyun if (diag304->args[1] == DIAG304_QUERY_PRP)
101*4882a593Smuzhiyun if (copy_to_user(udata, data, PAGE_SIZE)) {
102*4882a593Smuzhiyun rc = -EFAULT;
103*4882a593Smuzhiyun goto out;
104*4882a593Smuzhiyun }
105*4882a593Smuzhiyun
106*4882a593Smuzhiyun rc = copy_to_user(user_area, diag304, sizeof(*diag304)) ? -EFAULT : 0;
107*4882a593Smuzhiyun out:
108*4882a593Smuzhiyun kfree(diag304);
109*4882a593Smuzhiyun free_page((unsigned long) data);
110*4882a593Smuzhiyun return rc;
111*4882a593Smuzhiyun }
112*4882a593Smuzhiyun
hypfs_sprp_ioctl(struct file * file,unsigned int cmd,unsigned long arg)113*4882a593Smuzhiyun static long hypfs_sprp_ioctl(struct file *file, unsigned int cmd,
114*4882a593Smuzhiyun unsigned long arg)
115*4882a593Smuzhiyun {
116*4882a593Smuzhiyun void __user *argp;
117*4882a593Smuzhiyun
118*4882a593Smuzhiyun if (!capable(CAP_SYS_ADMIN))
119*4882a593Smuzhiyun return -EACCES;
120*4882a593Smuzhiyun if (is_compat_task())
121*4882a593Smuzhiyun argp = compat_ptr(arg);
122*4882a593Smuzhiyun else
123*4882a593Smuzhiyun argp = (void __user *) arg;
124*4882a593Smuzhiyun switch (cmd) {
125*4882a593Smuzhiyun case HYPFS_DIAG304:
126*4882a593Smuzhiyun return __hypfs_sprp_ioctl(argp);
127*4882a593Smuzhiyun default: /* unknown ioctl number */
128*4882a593Smuzhiyun return -ENOTTY;
129*4882a593Smuzhiyun }
130*4882a593Smuzhiyun return 0;
131*4882a593Smuzhiyun }
132*4882a593Smuzhiyun
133*4882a593Smuzhiyun static struct hypfs_dbfs_file hypfs_sprp_file = {
134*4882a593Smuzhiyun .name = "diag_304",
135*4882a593Smuzhiyun .data_create = hypfs_sprp_create,
136*4882a593Smuzhiyun .data_free = hypfs_sprp_free,
137*4882a593Smuzhiyun .unlocked_ioctl = hypfs_sprp_ioctl,
138*4882a593Smuzhiyun };
139*4882a593Smuzhiyun
hypfs_sprp_init(void)140*4882a593Smuzhiyun void hypfs_sprp_init(void)
141*4882a593Smuzhiyun {
142*4882a593Smuzhiyun if (!sclp.has_sprp)
143*4882a593Smuzhiyun return;
144*4882a593Smuzhiyun hypfs_dbfs_create_file(&hypfs_sprp_file);
145*4882a593Smuzhiyun }
146*4882a593Smuzhiyun
hypfs_sprp_exit(void)147*4882a593Smuzhiyun void hypfs_sprp_exit(void)
148*4882a593Smuzhiyun {
149*4882a593Smuzhiyun if (!sclp.has_sprp)
150*4882a593Smuzhiyun return;
151*4882a593Smuzhiyun hypfs_dbfs_remove_file(&hypfs_sprp_file);
152*4882a593Smuzhiyun }
153