xref: /openbmc/linux/arch/s390/hypfs/hypfs_vm.c (revision 6b342707)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *    Hypervisor filesystem for Linux on s390. z/VM implementation.
4  *
5  *    Copyright IBM Corp. 2006
6  *    Author(s): Michael Holzheu <holzheu@de.ibm.com>
7  */
8 
9 #include <linux/types.h>
10 #include <linux/errno.h>
11 #include <linux/string.h>
12 #include <linux/vmalloc.h>
13 #include <asm/diag.h>
14 #include <asm/ebcdic.h>
15 #include <asm/timex.h>
16 #include "hypfs.h"
17 
18 #define NAME_LEN 8
19 #define DBFS_D2FC_HDR_VERSION 0
20 
21 static char local_guest[] = "        ";
22 static char all_guests[] = "*       ";
23 static char *all_groups = all_guests;
24 static char *guest_query;
25 
26 struct diag2fc_data {
27 	__u32 version;
28 	__u32 flags;
29 	__u64 used_cpu;
30 	__u64 el_time;
31 	__u64 mem_min_kb;
32 	__u64 mem_max_kb;
33 	__u64 mem_share_kb;
34 	__u64 mem_used_kb;
35 	__u32 pcpus;
36 	__u32 lcpus;
37 	__u32 vcpus;
38 	__u32 ocpus;
39 	__u32 cpu_max;
40 	__u32 cpu_shares;
41 	__u32 cpu_use_samp;
42 	__u32 cpu_delay_samp;
43 	__u32 page_wait_samp;
44 	__u32 idle_samp;
45 	__u32 other_samp;
46 	__u32 total_samp;
47 	char  guest_name[NAME_LEN];
48 };
49 
50 struct diag2fc_parm_list {
51 	char userid[NAME_LEN];
52 	char aci_grp[NAME_LEN];
53 	__u64 addr;
54 	__u32 size;
55 	__u32 fmt;
56 };
57 
58 static int diag2fc(int size, char* query, void *addr)
59 {
60 	unsigned long residual_cnt;
61 	unsigned long rc;
62 	struct diag2fc_parm_list parm_list;
63 
64 	memcpy(parm_list.userid, query, NAME_LEN);
65 	ASCEBC(parm_list.userid, NAME_LEN);
66 	memcpy(parm_list.aci_grp, all_groups, NAME_LEN);
67 	ASCEBC(parm_list.aci_grp, NAME_LEN);
68 	parm_list.addr = (unsigned long)addr;
69 	parm_list.size = size;
70 	parm_list.fmt = 0x02;
71 	rc = -1;
72 
73 	diag_stat_inc(DIAG_STAT_X2FC);
74 	asm volatile(
75 		"	diag    %0,%1,0x2fc\n"
76 		"0:	nopr	%%r7\n"
77 		EX_TABLE(0b,0b)
78 		: "=d" (residual_cnt), "+d" (rc) : "0" (&parm_list) : "memory");
79 
80 	if ((rc != 0 ) && (rc != -2))
81 		return rc;
82 	else
83 		return -residual_cnt;
84 }
85 
86 /*
87  * Allocate buffer for "query" and store diag 2fc at "offset"
88  */
89 static void *diag2fc_store(char *query, unsigned int *count, int offset)
90 {
91 	void *data;
92 	int size;
93 
94 	do {
95 		size = diag2fc(0, query, NULL);
96 		if (size < 0)
97 			return ERR_PTR(-EACCES);
98 		data = vmalloc(size + offset);
99 		if (!data)
100 			return ERR_PTR(-ENOMEM);
101 		if (diag2fc(size, query, data + offset) == 0)
102 			break;
103 		vfree(data);
104 	} while (1);
105 	*count = (size / sizeof(struct diag2fc_data));
106 
107 	return data;
108 }
109 
110 static void diag2fc_free(const void *data)
111 {
112 	vfree(data);
113 }
114 
115 #define ATTRIBUTE(dir, name, member) \
116 do { \
117 	void *rc; \
118 	rc = hypfs_create_u64(dir, name, member); \
119 	if (IS_ERR(rc)) \
120 		return PTR_ERR(rc); \
121 } while(0)
122 
123 static int hypfs_vm_create_guest(struct dentry *systems_dir,
124 				 struct diag2fc_data *data)
125 {
126 	char guest_name[NAME_LEN + 1] = {};
127 	struct dentry *guest_dir, *cpus_dir, *samples_dir, *mem_dir;
128 	int dedicated_flag, capped_value;
129 
130 	capped_value = (data->flags & 0x00000006) >> 1;
131 	dedicated_flag = (data->flags & 0x00000008) >> 3;
132 
133 	/* guest dir */
134 	memcpy(guest_name, data->guest_name, NAME_LEN);
135 	EBCASC(guest_name, NAME_LEN);
136 	strim(guest_name);
137 	guest_dir = hypfs_mkdir(systems_dir, guest_name);
138 	if (IS_ERR(guest_dir))
139 		return PTR_ERR(guest_dir);
140 	ATTRIBUTE(guest_dir, "onlinetime_us", data->el_time);
141 
142 	/* logical cpu information */
143 	cpus_dir = hypfs_mkdir(guest_dir, "cpus");
144 	if (IS_ERR(cpus_dir))
145 		return PTR_ERR(cpus_dir);
146 	ATTRIBUTE(cpus_dir, "cputime_us", data->used_cpu);
147 	ATTRIBUTE(cpus_dir, "capped", capped_value);
148 	ATTRIBUTE(cpus_dir, "dedicated", dedicated_flag);
149 	ATTRIBUTE(cpus_dir, "count", data->vcpus);
150 	/*
151 	 * Note: The "weight_min" attribute got the wrong name.
152 	 * The value represents the number of non-stopped (operating)
153 	 * CPUS.
154 	 */
155 	ATTRIBUTE(cpus_dir, "weight_min", data->ocpus);
156 	ATTRIBUTE(cpus_dir, "weight_max", data->cpu_max);
157 	ATTRIBUTE(cpus_dir, "weight_cur", data->cpu_shares);
158 
159 	/* memory information */
160 	mem_dir = hypfs_mkdir(guest_dir, "mem");
161 	if (IS_ERR(mem_dir))
162 		return PTR_ERR(mem_dir);
163 	ATTRIBUTE(mem_dir, "min_KiB", data->mem_min_kb);
164 	ATTRIBUTE(mem_dir, "max_KiB", data->mem_max_kb);
165 	ATTRIBUTE(mem_dir, "used_KiB", data->mem_used_kb);
166 	ATTRIBUTE(mem_dir, "share_KiB", data->mem_share_kb);
167 
168 	/* samples */
169 	samples_dir = hypfs_mkdir(guest_dir, "samples");
170 	if (IS_ERR(samples_dir))
171 		return PTR_ERR(samples_dir);
172 	ATTRIBUTE(samples_dir, "cpu_using", data->cpu_use_samp);
173 	ATTRIBUTE(samples_dir, "cpu_delay", data->cpu_delay_samp);
174 	ATTRIBUTE(samples_dir, "mem_delay", data->page_wait_samp);
175 	ATTRIBUTE(samples_dir, "idle", data->idle_samp);
176 	ATTRIBUTE(samples_dir, "other", data->other_samp);
177 	ATTRIBUTE(samples_dir, "total", data->total_samp);
178 	return 0;
179 }
180 
181 int hypfs_vm_create_files(struct dentry *root)
182 {
183 	struct dentry *dir, *file;
184 	struct diag2fc_data *data;
185 	unsigned int count = 0;
186 	int rc, i;
187 
188 	data = diag2fc_store(guest_query, &count, 0);
189 	if (IS_ERR(data))
190 		return PTR_ERR(data);
191 
192 	/* Hpervisor Info */
193 	dir = hypfs_mkdir(root, "hyp");
194 	if (IS_ERR(dir)) {
195 		rc = PTR_ERR(dir);
196 		goto failed;
197 	}
198 	file = hypfs_create_str(dir, "type", "z/VM Hypervisor");
199 	if (IS_ERR(file)) {
200 		rc = PTR_ERR(file);
201 		goto failed;
202 	}
203 
204 	/* physical cpus */
205 	dir = hypfs_mkdir(root, "cpus");
206 	if (IS_ERR(dir)) {
207 		rc = PTR_ERR(dir);
208 		goto failed;
209 	}
210 	file = hypfs_create_u64(dir, "count", data->lcpus);
211 	if (IS_ERR(file)) {
212 		rc = PTR_ERR(file);
213 		goto failed;
214 	}
215 
216 	/* guests */
217 	dir = hypfs_mkdir(root, "systems");
218 	if (IS_ERR(dir)) {
219 		rc = PTR_ERR(dir);
220 		goto failed;
221 	}
222 
223 	for (i = 0; i < count; i++) {
224 		rc = hypfs_vm_create_guest(dir, &(data[i]));
225 		if (rc)
226 			goto failed;
227 	}
228 	diag2fc_free(data);
229 	return 0;
230 
231 failed:
232 	diag2fc_free(data);
233 	return rc;
234 }
235 
236 struct dbfs_d2fc_hdr {
237 	u64	len;		/* Length of d2fc buffer without header */
238 	u16	version;	/* Version of header */
239 	union tod_clock tod_ext; /* TOD clock for d2fc */
240 	u64	count;		/* Number of VM guests in d2fc buffer */
241 	char	reserved[30];
242 } __attribute__ ((packed));
243 
244 struct dbfs_d2fc {
245 	struct dbfs_d2fc_hdr	hdr;	/* 64 byte header */
246 	char			buf[];	/* d2fc buffer */
247 } __attribute__ ((packed));
248 
249 static int dbfs_diag2fc_create(void **data, void **data_free_ptr, size_t *size)
250 {
251 	struct dbfs_d2fc *d2fc;
252 	unsigned int count;
253 
254 	d2fc = diag2fc_store(guest_query, &count, sizeof(d2fc->hdr));
255 	if (IS_ERR(d2fc))
256 		return PTR_ERR(d2fc);
257 	store_tod_clock_ext(&d2fc->hdr.tod_ext);
258 	d2fc->hdr.len = count * sizeof(struct diag2fc_data);
259 	d2fc->hdr.version = DBFS_D2FC_HDR_VERSION;
260 	d2fc->hdr.count = count;
261 	memset(&d2fc->hdr.reserved, 0, sizeof(d2fc->hdr.reserved));
262 	*data = d2fc;
263 	*data_free_ptr = d2fc;
264 	*size = d2fc->hdr.len + sizeof(struct dbfs_d2fc_hdr);
265 	return 0;
266 }
267 
268 static struct hypfs_dbfs_file dbfs_file_2fc = {
269 	.name		= "diag_2fc",
270 	.data_create	= dbfs_diag2fc_create,
271 	.data_free	= diag2fc_free,
272 };
273 
274 int hypfs_vm_init(void)
275 {
276 	if (!MACHINE_IS_VM)
277 		return 0;
278 	if (diag2fc(0, all_guests, NULL) > 0)
279 		guest_query = all_guests;
280 	else if (diag2fc(0, local_guest, NULL) > 0)
281 		guest_query = local_guest;
282 	else
283 		return -EACCES;
284 	hypfs_dbfs_create_file(&dbfs_file_2fc);
285 	return 0;
286 }
287 
288 void hypfs_vm_exit(void)
289 {
290 	if (!MACHINE_IS_VM)
291 		return;
292 	hypfs_dbfs_remove_file(&dbfs_file_2fc);
293 }
294