1 // SPDX-License-Identifier: GPL-2.0
3 * Hypervisor filesystem for Linux on s390
5 * Diag 0C implementation
7 * Copyright IBM Corp. 2014
10 #include <linux/slab.h>
11 #include <linux/cpu.h>
13 #include <asm/hypfs.h>
16 #define DBFS_D0C_HDR_VERSION 0
19 * Execute diagnose 0c in 31 bit mode
21 static void diag0c(struct hypfs_diag0c_entry *entry)
23 diag_stat_inc(DIAG_STAT_X00C);
28 : /* no output register */
34 * Get hypfs_diag0c_entry from CPU vector and store diag0c data
36 static void diag0c_fn(void *data)
38 diag0c(((void **) data)[smp_processor_id()]);
42 * Allocate buffer and store diag 0c data
44 static void *diag0c_store(unsigned int *count)
46 struct hypfs_diag0c_data *diag0c_data;
47 unsigned int cpu_count, cpu, i;
51 cpu_count = num_online_cpus();
52 cpu_vec = kmalloc(sizeof(*cpu_vec) * num_possible_cpus(), GFP_KERNEL);
54 goto fail_put_online_cpus;
55 /* Note: Diag 0c needs 8 byte alignment and real storage */
56 diag0c_data = kzalloc(sizeof(struct hypfs_diag0c_hdr) +
57 cpu_count * sizeof(struct hypfs_diag0c_entry),
58 GFP_KERNEL | GFP_DMA);
60 goto fail_kfree_cpu_vec;
62 /* Fill CPU vector for each online CPU */
63 for_each_online_cpu(cpu) {
64 diag0c_data->entry[i].cpu = cpu;
65 cpu_vec[cpu] = &diag0c_data->entry[i++];
67 /* Collect data all CPUs */
68 on_each_cpu(diag0c_fn, cpu_vec, 1);
78 return ERR_PTR(-ENOMEM);
82 * Hypfs DBFS callback: Free diag 0c data
84 static void dbfs_diag0c_free(const void *data)
90 * Hypfs DBFS callback: Create diag 0c data
92 static int dbfs_diag0c_create(void **data, void **data_free_ptr, size_t *size)
94 struct hypfs_diag0c_data *diag0c_data;
97 diag0c_data = diag0c_store(&count);
98 if (IS_ERR(diag0c_data))
99 return PTR_ERR(diag0c_data);
100 memset(&diag0c_data->hdr, 0, sizeof(diag0c_data->hdr));
101 get_tod_clock_ext(diag0c_data->hdr.tod_ext);
102 diag0c_data->hdr.len = count * sizeof(struct hypfs_diag0c_entry);
103 diag0c_data->hdr.version = DBFS_D0C_HDR_VERSION;
104 diag0c_data->hdr.count = count;
106 *data_free_ptr = diag0c_data;
107 *size = diag0c_data->hdr.len + sizeof(struct hypfs_diag0c_hdr);
112 * Hypfs DBFS file structure
114 static struct hypfs_dbfs_file dbfs_file_0c = {
116 .data_create = dbfs_diag0c_create,
117 .data_free = dbfs_diag0c_free,
121 * Initialize diag 0c interface for z/VM
123 int __init hypfs_diag0c_init(void)
127 return hypfs_dbfs_create_file(&dbfs_file_0c);
131 * Shutdown diag 0c interface for z/VM
133 void hypfs_diag0c_exit(void)
137 hypfs_dbfs_remove_file(&dbfs_file_0c);