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/extable.h>
14 #include <asm/diag.h>
15 #include <asm/ebcdic.h>
16 #include <asm/timex.h>
17 #include "hypfs.h"
18 
19 #define NAME_LEN 8
20 #define DBFS_D2FC_HDR_VERSION 0
21 
22 static char local_guest[] = "        ";
23 static char all_guests[] = "*       ";
24 static char *all_groups = all_guests;
25 static char *guest_query;
26 
27 struct diag2fc_data {
28 	__u32 version;
29 	__u32 flags;
30 	__u64 used_cpu;
31 	__u64 el_time;
32 	__u64 mem_min_kb;
33 	__u64 mem_max_kb;
34 	__u64 mem_share_kb;
35 	__u64 mem_used_kb;
36 	__u32 pcpus;
37 	__u32 lcpus;
38 	__u32 vcpus;
39 	__u32 ocpus;
40 	__u32 cpu_max;
41 	__u32 cpu_shares;
42 	__u32 cpu_use_samp;
43 	__u32 cpu_delay_samp;
44 	__u32 page_wait_samp;
45 	__u32 idle_samp;
46 	__u32 other_samp;
47 	__u32 total_samp;
48 	char  guest_name[NAME_LEN];
49 };
50 
51 struct diag2fc_parm_list {
52 	char userid[NAME_LEN];
53 	char aci_grp[NAME_LEN];
54 	__u64 addr;
55 	__u32 size;
56 	__u32 fmt;
57 };
58 
diag2fc(int size,char * query,void * addr)59 static int diag2fc(int size, char* query, void *addr)
60 {
61 	unsigned long residual_cnt;
62 	unsigned long rc;
63 	struct diag2fc_parm_list parm_list;
64 
65 	memcpy(parm_list.userid, query, NAME_LEN);
66 	ASCEBC(parm_list.userid, NAME_LEN);
67 	memcpy(parm_list.aci_grp, all_groups, NAME_LEN);
68 	ASCEBC(parm_list.aci_grp, NAME_LEN);
69 	parm_list.addr = (unsigned long)addr;
70 	parm_list.size = size;
71 	parm_list.fmt = 0x02;
72 	rc = -1;
73 
74 	diag_stat_inc(DIAG_STAT_X2FC);
75 	asm volatile(
76 		"	diag    %0,%1,0x2fc\n"
77 		"0:	nopr	%%r7\n"
78 		EX_TABLE(0b,0b)
79 		: "=d" (residual_cnt), "+d" (rc) : "0" (&parm_list) : "memory");
80 
81 	if ((rc != 0 ) && (rc != -2))
82 		return rc;
83 	else
84 		return -residual_cnt;
85 }
86 
87 /*
88  * Allocate buffer for "query" and store diag 2fc at "offset"
89  */
diag2fc_store(char * query,unsigned int * count,int offset)90 static void *diag2fc_store(char *query, unsigned int *count, int offset)
91 {
92 	void *data;
93 	int size;
94 
95 	do {
96 		size = diag2fc(0, query, NULL);
97 		if (size < 0)
98 			return ERR_PTR(-EACCES);
99 		data = vmalloc(size + offset);
100 		if (!data)
101 			return ERR_PTR(-ENOMEM);
102 		if (diag2fc(size, query, data + offset) == 0)
103 			break;
104 		vfree(data);
105 	} while (1);
106 	*count = (size / sizeof(struct diag2fc_data));
107 
108 	return data;
109 }
110 
diag2fc_free(const void * data)111 static void diag2fc_free(const void *data)
112 {
113 	vfree(data);
114 }
115 
116 #define ATTRIBUTE(dir, name, member) \
117 do { \
118 	void *rc; \
119 	rc = hypfs_create_u64(dir, name, member); \
120 	if (IS_ERR(rc)) \
121 		return PTR_ERR(rc); \
122 } while(0)
123 
hypfs_vm_create_guest(struct dentry * systems_dir,struct diag2fc_data * data)124 static int hypfs_vm_create_guest(struct dentry *systems_dir,
125 				 struct diag2fc_data *data)
126 {
127 	char guest_name[NAME_LEN + 1] = {};
128 	struct dentry *guest_dir, *cpus_dir, *samples_dir, *mem_dir;
129 	int dedicated_flag, capped_value;
130 
131 	capped_value = (data->flags & 0x00000006) >> 1;
132 	dedicated_flag = (data->flags & 0x00000008) >> 3;
133 
134 	/* guest dir */
135 	memcpy(guest_name, data->guest_name, NAME_LEN);
136 	EBCASC(guest_name, NAME_LEN);
137 	strim(guest_name);
138 	guest_dir = hypfs_mkdir(systems_dir, guest_name);
139 	if (IS_ERR(guest_dir))
140 		return PTR_ERR(guest_dir);
141 	ATTRIBUTE(guest_dir, "onlinetime_us", data->el_time);
142 
143 	/* logical cpu information */
144 	cpus_dir = hypfs_mkdir(guest_dir, "cpus");
145 	if (IS_ERR(cpus_dir))
146 		return PTR_ERR(cpus_dir);
147 	ATTRIBUTE(cpus_dir, "cputime_us", data->used_cpu);
148 	ATTRIBUTE(cpus_dir, "capped", capped_value);
149 	ATTRIBUTE(cpus_dir, "dedicated", dedicated_flag);
150 	ATTRIBUTE(cpus_dir, "count", data->vcpus);
151 	/*
152 	 * Note: The "weight_min" attribute got the wrong name.
153 	 * The value represents the number of non-stopped (operating)
154 	 * CPUS.
155 	 */
156 	ATTRIBUTE(cpus_dir, "weight_min", data->ocpus);
157 	ATTRIBUTE(cpus_dir, "weight_max", data->cpu_max);
158 	ATTRIBUTE(cpus_dir, "weight_cur", data->cpu_shares);
159 
160 	/* memory information */
161 	mem_dir = hypfs_mkdir(guest_dir, "mem");
162 	if (IS_ERR(mem_dir))
163 		return PTR_ERR(mem_dir);
164 	ATTRIBUTE(mem_dir, "min_KiB", data->mem_min_kb);
165 	ATTRIBUTE(mem_dir, "max_KiB", data->mem_max_kb);
166 	ATTRIBUTE(mem_dir, "used_KiB", data->mem_used_kb);
167 	ATTRIBUTE(mem_dir, "share_KiB", data->mem_share_kb);
168 
169 	/* samples */
170 	samples_dir = hypfs_mkdir(guest_dir, "samples");
171 	if (IS_ERR(samples_dir))
172 		return PTR_ERR(samples_dir);
173 	ATTRIBUTE(samples_dir, "cpu_using", data->cpu_use_samp);
174 	ATTRIBUTE(samples_dir, "cpu_delay", data->cpu_delay_samp);
175 	ATTRIBUTE(samples_dir, "mem_delay", data->page_wait_samp);
176 	ATTRIBUTE(samples_dir, "idle", data->idle_samp);
177 	ATTRIBUTE(samples_dir, "other", data->other_samp);
178 	ATTRIBUTE(samples_dir, "total", data->total_samp);
179 	return 0;
180 }
181 
hypfs_vm_create_files(struct dentry * root)182 int hypfs_vm_create_files(struct dentry *root)
183 {
184 	struct dentry *dir, *file;
185 	struct diag2fc_data *data;
186 	unsigned int count = 0;
187 	int rc, i;
188 
189 	data = diag2fc_store(guest_query, &count, 0);
190 	if (IS_ERR(data))
191 		return PTR_ERR(data);
192 
193 	/* Hypervisor Info */
194 	dir = hypfs_mkdir(root, "hyp");
195 	if (IS_ERR(dir)) {
196 		rc = PTR_ERR(dir);
197 		goto failed;
198 	}
199 	file = hypfs_create_str(dir, "type", "z/VM Hypervisor");
200 	if (IS_ERR(file)) {
201 		rc = PTR_ERR(file);
202 		goto failed;
203 	}
204 
205 	/* physical cpus */
206 	dir = hypfs_mkdir(root, "cpus");
207 	if (IS_ERR(dir)) {
208 		rc = PTR_ERR(dir);
209 		goto failed;
210 	}
211 	file = hypfs_create_u64(dir, "count", data->lcpus);
212 	if (IS_ERR(file)) {
213 		rc = PTR_ERR(file);
214 		goto failed;
215 	}
216 
217 	/* guests */
218 	dir = hypfs_mkdir(root, "systems");
219 	if (IS_ERR(dir)) {
220 		rc = PTR_ERR(dir);
221 		goto failed;
222 	}
223 
224 	for (i = 0; i < count; i++) {
225 		rc = hypfs_vm_create_guest(dir, &(data[i]));
226 		if (rc)
227 			goto failed;
228 	}
229 	diag2fc_free(data);
230 	return 0;
231 
232 failed:
233 	diag2fc_free(data);
234 	return rc;
235 }
236 
237 struct dbfs_d2fc_hdr {
238 	u64	len;		/* Length of d2fc buffer without header */
239 	u16	version;	/* Version of header */
240 	union tod_clock tod_ext; /* TOD clock for d2fc */
241 	u64	count;		/* Number of VM guests in d2fc buffer */
242 	char	reserved[30];
243 } __attribute__ ((packed));
244 
245 struct dbfs_d2fc {
246 	struct dbfs_d2fc_hdr	hdr;	/* 64 byte header */
247 	char			buf[];	/* d2fc buffer */
248 } __attribute__ ((packed));
249 
dbfs_diag2fc_create(void ** data,void ** data_free_ptr,size_t * size)250 static int dbfs_diag2fc_create(void **data, void **data_free_ptr, size_t *size)
251 {
252 	struct dbfs_d2fc *d2fc;
253 	unsigned int count;
254 
255 	d2fc = diag2fc_store(guest_query, &count, sizeof(d2fc->hdr));
256 	if (IS_ERR(d2fc))
257 		return PTR_ERR(d2fc);
258 	store_tod_clock_ext(&d2fc->hdr.tod_ext);
259 	d2fc->hdr.len = count * sizeof(struct diag2fc_data);
260 	d2fc->hdr.version = DBFS_D2FC_HDR_VERSION;
261 	d2fc->hdr.count = count;
262 	memset(&d2fc->hdr.reserved, 0, sizeof(d2fc->hdr.reserved));
263 	*data = d2fc;
264 	*data_free_ptr = d2fc;
265 	*size = d2fc->hdr.len + sizeof(struct dbfs_d2fc_hdr);
266 	return 0;
267 }
268 
269 static struct hypfs_dbfs_file dbfs_file_2fc = {
270 	.name		= "diag_2fc",
271 	.data_create	= dbfs_diag2fc_create,
272 	.data_free	= diag2fc_free,
273 };
274 
hypfs_vm_init(void)275 int hypfs_vm_init(void)
276 {
277 	if (!MACHINE_IS_VM)
278 		return 0;
279 	if (diag2fc(0, all_guests, NULL) > 0)
280 		guest_query = all_guests;
281 	else if (diag2fc(0, local_guest, NULL) > 0)
282 		guest_query = local_guest;
283 	else
284 		return -EACCES;
285 	hypfs_dbfs_create_file(&dbfs_file_2fc);
286 	return 0;
287 }
288 
hypfs_vm_exit(void)289 void hypfs_vm_exit(void)
290 {
291 	if (!MACHINE_IS_VM)
292 		return;
293 	hypfs_dbfs_remove_file(&dbfs_file_2fc);
294 }
295