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_array(num_possible_cpus(), sizeof(*cpu_vec),
55 goto fail_put_online_cpus;
56 /* Note: Diag 0c needs 8 byte alignment and real storage */
57 diag0c_data = kzalloc(sizeof(struct hypfs_diag0c_hdr) +
58 cpu_count * sizeof(struct hypfs_diag0c_entry),
59 GFP_KERNEL | GFP_DMA);
61 goto fail_kfree_cpu_vec;
63 /* Fill CPU vector for each online CPU */
64 for_each_online_cpu(cpu) {
65 diag0c_data->entry[i].cpu = cpu;
66 cpu_vec[cpu] = &diag0c_data->entry[i++];
68 /* Collect data all CPUs */
69 on_each_cpu(diag0c_fn, cpu_vec, 1);
79 return ERR_PTR(-ENOMEM);
83 * Hypfs DBFS callback: Free diag 0c data
85 static void dbfs_diag0c_free(const void *data)
91 * Hypfs DBFS callback: Create diag 0c data
93 static int dbfs_diag0c_create(void **data, void **data_free_ptr, size_t *size)
95 struct hypfs_diag0c_data *diag0c_data;
98 diag0c_data = diag0c_store(&count);
99 if (IS_ERR(diag0c_data))
100 return PTR_ERR(diag0c_data);
101 memset(&diag0c_data->hdr, 0, sizeof(diag0c_data->hdr));
102 get_tod_clock_ext(diag0c_data->hdr.tod_ext);
103 diag0c_data->hdr.len = count * sizeof(struct hypfs_diag0c_entry);
104 diag0c_data->hdr.version = DBFS_D0C_HDR_VERSION;
105 diag0c_data->hdr.count = count;
107 *data_free_ptr = diag0c_data;
108 *size = diag0c_data->hdr.len + sizeof(struct hypfs_diag0c_hdr);
113 * Hypfs DBFS file structure
115 static struct hypfs_dbfs_file dbfs_file_0c = {
117 .data_create = dbfs_diag0c_create,
118 .data_free = dbfs_diag0c_free,
122 * Initialize diag 0c interface for z/VM
124 int __init hypfs_diag0c_init(void)
128 return hypfs_dbfs_create_file(&dbfs_file_0c);
132 * Shutdown diag 0c interface for z/VM
134 void hypfs_diag0c_exit(void)
138 hypfs_dbfs_remove_file(&dbfs_file_0c);