linux-sg2042/arch/s390/hypfs/hypfs_diag0c.c

140 lines
3.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Hypervisor filesystem for Linux on s390
*
* Diag 0C implementation
*
* Copyright IBM Corp. 2014
*/
#include <linux/slab.h>
#include <linux/cpu.h>
#include <asm/diag.h>
#include <asm/hypfs.h>
#include "hypfs.h"
#define DBFS_D0C_HDR_VERSION 0
/*
* Execute diagnose 0c in 31 bit mode
*/
static void diag0c(struct hypfs_diag0c_entry *entry)
{
diag_stat_inc(DIAG_STAT_X00C);
asm volatile (
" sam31\n"
" diag %0,%0,0x0c\n"
" sam64\n"
: /* no output register */
: "a" (entry)
: "memory");
}
/*
* Get hypfs_diag0c_entry from CPU vector and store diag0c data
*/
static void diag0c_fn(void *data)
{
diag0c(((void **) data)[smp_processor_id()]);
}
/*
* Allocate buffer and store diag 0c data
*/
static void *diag0c_store(unsigned int *count)
{
struct hypfs_diag0c_data *diag0c_data;
unsigned int cpu_count, cpu, i;
void **cpu_vec;
get_online_cpus();
cpu_count = num_online_cpus();
cpu_vec = kmalloc_array(num_possible_cpus(), sizeof(*cpu_vec),
GFP_KERNEL);
if (!cpu_vec)
goto fail_put_online_cpus;
/* Note: Diag 0c needs 8 byte alignment and real storage */
diag0c_data = kzalloc(sizeof(struct hypfs_diag0c_hdr) +
cpu_count * sizeof(struct hypfs_diag0c_entry),
GFP_KERNEL | GFP_DMA);
if (!diag0c_data)
goto fail_kfree_cpu_vec;
i = 0;
/* Fill CPU vector for each online CPU */
for_each_online_cpu(cpu) {
diag0c_data->entry[i].cpu = cpu;
cpu_vec[cpu] = &diag0c_data->entry[i++];
}
/* Collect data all CPUs */
on_each_cpu(diag0c_fn, cpu_vec, 1);
*count = cpu_count;
kfree(cpu_vec);
put_online_cpus();
return diag0c_data;
fail_kfree_cpu_vec:
kfree(cpu_vec);
fail_put_online_cpus:
put_online_cpus();
return ERR_PTR(-ENOMEM);
}
/*
* Hypfs DBFS callback: Free diag 0c data
*/
static void dbfs_diag0c_free(const void *data)
{
kfree(data);
}
/*
* Hypfs DBFS callback: Create diag 0c data
*/
static int dbfs_diag0c_create(void **data, void **data_free_ptr, size_t *size)
{
struct hypfs_diag0c_data *diag0c_data;
unsigned int count;
diag0c_data = diag0c_store(&count);
if (IS_ERR(diag0c_data))
return PTR_ERR(diag0c_data);
memset(&diag0c_data->hdr, 0, sizeof(diag0c_data->hdr));
get_tod_clock_ext(diag0c_data->hdr.tod_ext);
diag0c_data->hdr.len = count * sizeof(struct hypfs_diag0c_entry);
diag0c_data->hdr.version = DBFS_D0C_HDR_VERSION;
diag0c_data->hdr.count = count;
*data = diag0c_data;
*data_free_ptr = diag0c_data;
*size = diag0c_data->hdr.len + sizeof(struct hypfs_diag0c_hdr);
return 0;
}
/*
* Hypfs DBFS file structure
*/
static struct hypfs_dbfs_file dbfs_file_0c = {
.name = "diag_0c",
.data_create = dbfs_diag0c_create,
.data_free = dbfs_diag0c_free,
};
/*
* Initialize diag 0c interface for z/VM
*/
int __init hypfs_diag0c_init(void)
{
if (!MACHINE_IS_VM)
return 0;
return hypfs_dbfs_create_file(&dbfs_file_0c);
}
/*
* Shutdown diag 0c interface for z/VM
*/
void hypfs_diag0c_exit(void)
{
if (!MACHINE_IS_VM)
return;
hypfs_dbfs_remove_file(&dbfs_file_0c);
}