linux/arch/s390/hypfs/hypfs_diag.c
Michael Holzheu 237d6e6884 s390/hypfs: Use get_free_page() instead of kmalloc to ensure page alignment
Since commit d86bd1bece ("mm/slub: support left redzone") it is no longer
guaranteed that kmalloc(PAGE_SIZE) returns page aligned memory.

After the above commit we get an error for diag224 because aligned
memory is required. This leads to the following user visible error:

 # mount none -t s390_hypfs /sys/hypervisor/
 mount: unknown filesystem type 's390_hypfs'

 # dmesg | grep hypfs
 hypfs.cccfb8: The hardware system does not provide all functions
               required by hypfs
 hypfs.7a79f0: Initialization of hypfs failed with rc=-61

Fix this problem and use get_free_page() instead of kmalloc() to get
correctly aligned memory.

Cc: stable@vger.kernel.org # v3.6+
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-10-28 10:08:58 +02:00

616 lines
16 KiB
C

/*
* Hypervisor filesystem for Linux on s390. Diag 204 and 224
* implementation.
*
* Copyright IBM Corp. 2006, 2008
* Author(s): Michael Holzheu <holzheu@de.ibm.com>
*/
#define KMSG_COMPONENT "hypfs"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/vmalloc.h>
#include <linux/mm.h>
#include <asm/diag.h>
#include <asm/ebcdic.h>
#include "hypfs.h"
#define TMP_SIZE 64 /* size of temporary buffers */
#define DBFS_D204_HDR_VERSION 0
static char *diag224_cpu_names; /* diag 224 name table */
static enum diag204_sc diag204_store_sc; /* used subcode for store */
static enum diag204_format diag204_info_type; /* used diag 204 data format */
static void *diag204_buf; /* 4K aligned buffer for diag204 data */
static void *diag204_buf_vmalloc; /* vmalloc pointer for diag204 data */
static int diag204_buf_pages; /* number of pages for diag204 data */
static struct dentry *dbfs_d204_file;
/*
* DIAG 204 member access functions.
*
* Since we have two different diag 204 data formats for old and new s390
* machines, we do not access the structs directly, but use getter functions for
* each struct member instead. This should make the code more readable.
*/
/* Time information block */
static inline int info_blk_hdr__size(enum diag204_format type)
{
if (type == DIAG204_INFO_SIMPLE)
return sizeof(struct diag204_info_blk_hdr);
else /* DIAG204_INFO_EXT */
return sizeof(struct diag204_x_info_blk_hdr);
}
static inline __u8 info_blk_hdr__npar(enum diag204_format type, void *hdr)
{
if (type == DIAG204_INFO_SIMPLE)
return ((struct diag204_info_blk_hdr *)hdr)->npar;
else /* DIAG204_INFO_EXT */
return ((struct diag204_x_info_blk_hdr *)hdr)->npar;
}
static inline __u8 info_blk_hdr__flags(enum diag204_format type, void *hdr)
{
if (type == DIAG204_INFO_SIMPLE)
return ((struct diag204_info_blk_hdr *)hdr)->flags;
else /* DIAG204_INFO_EXT */
return ((struct diag204_x_info_blk_hdr *)hdr)->flags;
}
static inline __u16 info_blk_hdr__pcpus(enum diag204_format type, void *hdr)
{
if (type == DIAG204_INFO_SIMPLE)
return ((struct diag204_info_blk_hdr *)hdr)->phys_cpus;
else /* DIAG204_INFO_EXT */
return ((struct diag204_x_info_blk_hdr *)hdr)->phys_cpus;
}
/* Partition header */
static inline int part_hdr__size(enum diag204_format type)
{
if (type == DIAG204_INFO_SIMPLE)
return sizeof(struct diag204_part_hdr);
else /* DIAG204_INFO_EXT */
return sizeof(struct diag204_x_part_hdr);
}
static inline __u8 part_hdr__rcpus(enum diag204_format type, void *hdr)
{
if (type == DIAG204_INFO_SIMPLE)
return ((struct diag204_part_hdr *)hdr)->cpus;
else /* DIAG204_INFO_EXT */
return ((struct diag204_x_part_hdr *)hdr)->rcpus;
}
static inline void part_hdr__part_name(enum diag204_format type, void *hdr,
char *name)
{
if (type == DIAG204_INFO_SIMPLE)
memcpy(name, ((struct diag204_part_hdr *)hdr)->part_name,
DIAG204_LPAR_NAME_LEN);
else /* DIAG204_INFO_EXT */
memcpy(name, ((struct diag204_x_part_hdr *)hdr)->part_name,
DIAG204_LPAR_NAME_LEN);
EBCASC(name, DIAG204_LPAR_NAME_LEN);
name[DIAG204_LPAR_NAME_LEN] = 0;
strim(name);
}
/* CPU info block */
static inline int cpu_info__size(enum diag204_format type)
{
if (type == DIAG204_INFO_SIMPLE)
return sizeof(struct diag204_cpu_info);
else /* DIAG204_INFO_EXT */
return sizeof(struct diag204_x_cpu_info);
}
static inline __u8 cpu_info__ctidx(enum diag204_format type, void *hdr)
{
if (type == DIAG204_INFO_SIMPLE)
return ((struct diag204_cpu_info *)hdr)->ctidx;
else /* DIAG204_INFO_EXT */
return ((struct diag204_x_cpu_info *)hdr)->ctidx;
}
static inline __u16 cpu_info__cpu_addr(enum diag204_format type, void *hdr)
{
if (type == DIAG204_INFO_SIMPLE)
return ((struct diag204_cpu_info *)hdr)->cpu_addr;
else /* DIAG204_INFO_EXT */
return ((struct diag204_x_cpu_info *)hdr)->cpu_addr;
}
static inline __u64 cpu_info__acc_time(enum diag204_format type, void *hdr)
{
if (type == DIAG204_INFO_SIMPLE)
return ((struct diag204_cpu_info *)hdr)->acc_time;
else /* DIAG204_INFO_EXT */
return ((struct diag204_x_cpu_info *)hdr)->acc_time;
}
static inline __u64 cpu_info__lp_time(enum diag204_format type, void *hdr)
{
if (type == DIAG204_INFO_SIMPLE)
return ((struct diag204_cpu_info *)hdr)->lp_time;
else /* DIAG204_INFO_EXT */
return ((struct diag204_x_cpu_info *)hdr)->lp_time;
}
static inline __u64 cpu_info__online_time(enum diag204_format type, void *hdr)
{
if (type == DIAG204_INFO_SIMPLE)
return 0; /* online_time not available in simple info */
else /* DIAG204_INFO_EXT */
return ((struct diag204_x_cpu_info *)hdr)->online_time;
}
/* Physical header */
static inline int phys_hdr__size(enum diag204_format type)
{
if (type == DIAG204_INFO_SIMPLE)
return sizeof(struct diag204_phys_hdr);
else /* DIAG204_INFO_EXT */
return sizeof(struct diag204_x_phys_hdr);
}
static inline __u8 phys_hdr__cpus(enum diag204_format type, void *hdr)
{
if (type == DIAG204_INFO_SIMPLE)
return ((struct diag204_phys_hdr *)hdr)->cpus;
else /* DIAG204_INFO_EXT */
return ((struct diag204_x_phys_hdr *)hdr)->cpus;
}
/* Physical CPU info block */
static inline int phys_cpu__size(enum diag204_format type)
{
if (type == DIAG204_INFO_SIMPLE)
return sizeof(struct diag204_phys_cpu);
else /* DIAG204_INFO_EXT */
return sizeof(struct diag204_x_phys_cpu);
}
static inline __u16 phys_cpu__cpu_addr(enum diag204_format type, void *hdr)
{
if (type == DIAG204_INFO_SIMPLE)
return ((struct diag204_phys_cpu *)hdr)->cpu_addr;
else /* DIAG204_INFO_EXT */
return ((struct diag204_x_phys_cpu *)hdr)->cpu_addr;
}
static inline __u64 phys_cpu__mgm_time(enum diag204_format type, void *hdr)
{
if (type == DIAG204_INFO_SIMPLE)
return ((struct diag204_phys_cpu *)hdr)->mgm_time;
else /* DIAG204_INFO_EXT */
return ((struct diag204_x_phys_cpu *)hdr)->mgm_time;
}
static inline __u64 phys_cpu__ctidx(enum diag204_format type, void *hdr)
{
if (type == DIAG204_INFO_SIMPLE)
return ((struct diag204_phys_cpu *)hdr)->ctidx;
else /* DIAG204_INFO_EXT */
return ((struct diag204_x_phys_cpu *)hdr)->ctidx;
}
/* Diagnose 204 functions */
/*
* For the old diag subcode 4 with simple data format we have to use real
* memory. If we use subcode 6 or 7 with extended data format, we can (and
* should) use vmalloc, since we need a lot of memory in that case. Currently
* up to 93 pages!
*/
static void diag204_free_buffer(void)
{
if (!diag204_buf)
return;
if (diag204_buf_vmalloc) {
vfree(diag204_buf_vmalloc);
diag204_buf_vmalloc = NULL;
} else {
free_pages((unsigned long) diag204_buf, 0);
}
diag204_buf = NULL;
}
static void *page_align_ptr(void *ptr)
{
return (void *) PAGE_ALIGN((unsigned long) ptr);
}
static void *diag204_alloc_vbuf(int pages)
{
/* The buffer has to be page aligned! */
diag204_buf_vmalloc = vmalloc(PAGE_SIZE * (pages + 1));
if (!diag204_buf_vmalloc)
return ERR_PTR(-ENOMEM);
diag204_buf = page_align_ptr(diag204_buf_vmalloc);
diag204_buf_pages = pages;
return diag204_buf;
}
static void *diag204_alloc_rbuf(void)
{
diag204_buf = (void*)__get_free_pages(GFP_KERNEL,0);
if (!diag204_buf)
return ERR_PTR(-ENOMEM);
diag204_buf_pages = 1;
return diag204_buf;
}
static void *diag204_get_buffer(enum diag204_format fmt, int *pages)
{
if (diag204_buf) {
*pages = diag204_buf_pages;
return diag204_buf;
}
if (fmt == DIAG204_INFO_SIMPLE) {
*pages = 1;
return diag204_alloc_rbuf();
} else {/* DIAG204_INFO_EXT */
*pages = diag204((unsigned long)DIAG204_SUBC_RSI |
(unsigned long)DIAG204_INFO_EXT, 0, NULL);
if (*pages <= 0)
return ERR_PTR(-ENOSYS);
else
return diag204_alloc_vbuf(*pages);
}
}
/*
* diag204_probe() has to find out, which type of diagnose 204 implementation
* we have on our machine. Currently there are three possible scanarios:
* - subcode 4 + simple data format (only one page)
* - subcode 4-6 + extended data format
* - subcode 4-7 + extended data format
*
* Subcode 5 is used to retrieve the size of the data, provided by subcodes
* 6 and 7. Subcode 7 basically has the same function as subcode 6. In addition
* to subcode 6 it provides also information about secondary cpus.
* In order to get as much information as possible, we first try
* subcode 7, then 6 and if both fail, we use subcode 4.
*/
static int diag204_probe(void)
{
void *buf;
int pages, rc;
buf = diag204_get_buffer(DIAG204_INFO_EXT, &pages);
if (!IS_ERR(buf)) {
if (diag204((unsigned long)DIAG204_SUBC_STIB7 |
(unsigned long)DIAG204_INFO_EXT, pages, buf) >= 0) {
diag204_store_sc = DIAG204_SUBC_STIB7;
diag204_info_type = DIAG204_INFO_EXT;
goto out;
}
if (diag204((unsigned long)DIAG204_SUBC_STIB6 |
(unsigned long)DIAG204_INFO_EXT, pages, buf) >= 0) {
diag204_store_sc = DIAG204_SUBC_STIB6;
diag204_info_type = DIAG204_INFO_EXT;
goto out;
}
diag204_free_buffer();
}
/* subcodes 6 and 7 failed, now try subcode 4 */
buf = diag204_get_buffer(DIAG204_INFO_SIMPLE, &pages);
if (IS_ERR(buf)) {
rc = PTR_ERR(buf);
goto fail_alloc;
}
if (diag204((unsigned long)DIAG204_SUBC_STIB4 |
(unsigned long)DIAG204_INFO_SIMPLE, pages, buf) >= 0) {
diag204_store_sc = DIAG204_SUBC_STIB4;
diag204_info_type = DIAG204_INFO_SIMPLE;
goto out;
} else {
rc = -ENOSYS;
goto fail_store;
}
out:
rc = 0;
fail_store:
diag204_free_buffer();
fail_alloc:
return rc;
}
static int diag204_do_store(void *buf, int pages)
{
int rc;
rc = diag204((unsigned long) diag204_store_sc |
(unsigned long) diag204_info_type, pages, buf);
return rc < 0 ? -ENOSYS : 0;
}
static void *diag204_store(void)
{
void *buf;
int pages, rc;
buf = diag204_get_buffer(diag204_info_type, &pages);
if (IS_ERR(buf))
goto out;
rc = diag204_do_store(buf, pages);
if (rc)
return ERR_PTR(rc);
out:
return buf;
}
/* Diagnose 224 functions */
static int diag224_get_name_table(void)
{
/* memory must be below 2GB */
diag224_cpu_names = (char *) __get_free_page(GFP_KERNEL | GFP_DMA);
if (!diag224_cpu_names)
return -ENOMEM;
if (diag224(diag224_cpu_names)) {
free_page((unsigned long) diag224_cpu_names);
return -EOPNOTSUPP;
}
EBCASC(diag224_cpu_names + 16, (*diag224_cpu_names + 1) * 16);
return 0;
}
static void diag224_delete_name_table(void)
{
free_page((unsigned long) diag224_cpu_names);
}
static int diag224_idx2name(int index, char *name)
{
memcpy(name, diag224_cpu_names + ((index + 1) * DIAG204_CPU_NAME_LEN),
DIAG204_CPU_NAME_LEN);
name[DIAG204_CPU_NAME_LEN] = 0;
strim(name);
return 0;
}
struct dbfs_d204_hdr {
u64 len; /* Length of d204 buffer without header */
u16 version; /* Version of header */
u8 sc; /* Used subcode */
char reserved[53];
} __attribute__ ((packed));
struct dbfs_d204 {
struct dbfs_d204_hdr hdr; /* 64 byte header */
char buf[]; /* d204 buffer */
} __attribute__ ((packed));
static int dbfs_d204_create(void **data, void **data_free_ptr, size_t *size)
{
struct dbfs_d204 *d204;
int rc, buf_size;
void *base;
buf_size = PAGE_SIZE * (diag204_buf_pages + 1) + sizeof(d204->hdr);
base = vzalloc(buf_size);
if (!base)
return -ENOMEM;
d204 = page_align_ptr(base + sizeof(d204->hdr)) - sizeof(d204->hdr);
rc = diag204_do_store(d204->buf, diag204_buf_pages);
if (rc) {
vfree(base);
return rc;
}
d204->hdr.version = DBFS_D204_HDR_VERSION;
d204->hdr.len = PAGE_SIZE * diag204_buf_pages;
d204->hdr.sc = diag204_store_sc;
*data = d204;
*data_free_ptr = base;
*size = d204->hdr.len + sizeof(struct dbfs_d204_hdr);
return 0;
}
static struct hypfs_dbfs_file dbfs_file_d204 = {
.name = "diag_204",
.data_create = dbfs_d204_create,
.data_free = vfree,
};
__init int hypfs_diag_init(void)
{
int rc;
if (diag204_probe()) {
pr_err("The hardware system does not support hypfs\n");
return -ENODATA;
}
if (diag204_info_type == DIAG204_INFO_EXT) {
rc = hypfs_dbfs_create_file(&dbfs_file_d204);
if (rc)
return rc;
}
if (MACHINE_IS_LPAR) {
rc = diag224_get_name_table();
if (rc) {
pr_err("The hardware system does not provide all "
"functions required by hypfs\n");
debugfs_remove(dbfs_d204_file);
return rc;
}
}
return 0;
}
void hypfs_diag_exit(void)
{
debugfs_remove(dbfs_d204_file);
diag224_delete_name_table();
diag204_free_buffer();
hypfs_dbfs_remove_file(&dbfs_file_d204);
}
/*
* Functions to create the directory structure
* *******************************************
*/
static int hypfs_create_cpu_files(struct dentry *cpus_dir, void *cpu_info)
{
struct dentry *cpu_dir;
char buffer[TMP_SIZE];
void *rc;
snprintf(buffer, TMP_SIZE, "%d", cpu_info__cpu_addr(diag204_info_type,
cpu_info));
cpu_dir = hypfs_mkdir(cpus_dir, buffer);
rc = hypfs_create_u64(cpu_dir, "mgmtime",
cpu_info__acc_time(diag204_info_type, cpu_info) -
cpu_info__lp_time(diag204_info_type, cpu_info));
if (IS_ERR(rc))
return PTR_ERR(rc);
rc = hypfs_create_u64(cpu_dir, "cputime",
cpu_info__lp_time(diag204_info_type, cpu_info));
if (IS_ERR(rc))
return PTR_ERR(rc);
if (diag204_info_type == DIAG204_INFO_EXT) {
rc = hypfs_create_u64(cpu_dir, "onlinetime",
cpu_info__online_time(diag204_info_type,
cpu_info));
if (IS_ERR(rc))
return PTR_ERR(rc);
}
diag224_idx2name(cpu_info__ctidx(diag204_info_type, cpu_info), buffer);
rc = hypfs_create_str(cpu_dir, "type", buffer);
return PTR_RET(rc);
}
static void *hypfs_create_lpar_files(struct dentry *systems_dir, void *part_hdr)
{
struct dentry *cpus_dir;
struct dentry *lpar_dir;
char lpar_name[DIAG204_LPAR_NAME_LEN + 1];
void *cpu_info;
int i;
part_hdr__part_name(diag204_info_type, part_hdr, lpar_name);
lpar_name[DIAG204_LPAR_NAME_LEN] = 0;
lpar_dir = hypfs_mkdir(systems_dir, lpar_name);
if (IS_ERR(lpar_dir))
return lpar_dir;
cpus_dir = hypfs_mkdir(lpar_dir, "cpus");
if (IS_ERR(cpus_dir))
return cpus_dir;
cpu_info = part_hdr + part_hdr__size(diag204_info_type);
for (i = 0; i < part_hdr__rcpus(diag204_info_type, part_hdr); i++) {
int rc;
rc = hypfs_create_cpu_files(cpus_dir, cpu_info);
if (rc)
return ERR_PTR(rc);
cpu_info += cpu_info__size(diag204_info_type);
}
return cpu_info;
}
static int hypfs_create_phys_cpu_files(struct dentry *cpus_dir, void *cpu_info)
{
struct dentry *cpu_dir;
char buffer[TMP_SIZE];
void *rc;
snprintf(buffer, TMP_SIZE, "%i", phys_cpu__cpu_addr(diag204_info_type,
cpu_info));
cpu_dir = hypfs_mkdir(cpus_dir, buffer);
if (IS_ERR(cpu_dir))
return PTR_ERR(cpu_dir);
rc = hypfs_create_u64(cpu_dir, "mgmtime",
phys_cpu__mgm_time(diag204_info_type, cpu_info));
if (IS_ERR(rc))
return PTR_ERR(rc);
diag224_idx2name(phys_cpu__ctidx(diag204_info_type, cpu_info), buffer);
rc = hypfs_create_str(cpu_dir, "type", buffer);
return PTR_RET(rc);
}
static void *hypfs_create_phys_files(struct dentry *parent_dir, void *phys_hdr)
{
int i;
void *cpu_info;
struct dentry *cpus_dir;
cpus_dir = hypfs_mkdir(parent_dir, "cpus");
if (IS_ERR(cpus_dir))
return cpus_dir;
cpu_info = phys_hdr + phys_hdr__size(diag204_info_type);
for (i = 0; i < phys_hdr__cpus(diag204_info_type, phys_hdr); i++) {
int rc;
rc = hypfs_create_phys_cpu_files(cpus_dir, cpu_info);
if (rc)
return ERR_PTR(rc);
cpu_info += phys_cpu__size(diag204_info_type);
}
return cpu_info;
}
int hypfs_diag_create_files(struct dentry *root)
{
struct dentry *systems_dir, *hyp_dir;
void *time_hdr, *part_hdr;
int i, rc;
void *buffer, *ptr;
buffer = diag204_store();
if (IS_ERR(buffer))
return PTR_ERR(buffer);
systems_dir = hypfs_mkdir(root, "systems");
if (IS_ERR(systems_dir)) {
rc = PTR_ERR(systems_dir);
goto err_out;
}
time_hdr = (struct x_info_blk_hdr *)buffer;
part_hdr = time_hdr + info_blk_hdr__size(diag204_info_type);
for (i = 0; i < info_blk_hdr__npar(diag204_info_type, time_hdr); i++) {
part_hdr = hypfs_create_lpar_files(systems_dir, part_hdr);
if (IS_ERR(part_hdr)) {
rc = PTR_ERR(part_hdr);
goto err_out;
}
}
if (info_blk_hdr__flags(diag204_info_type, time_hdr) &
DIAG204_LPAR_PHYS_FLG) {
ptr = hypfs_create_phys_files(root, part_hdr);
if (IS_ERR(ptr)) {
rc = PTR_ERR(ptr);
goto err_out;
}
}
hyp_dir = hypfs_mkdir(root, "hyp");
if (IS_ERR(hyp_dir)) {
rc = PTR_ERR(hyp_dir);
goto err_out;
}
ptr = hypfs_create_str(hyp_dir, "type", "LPAR Hypervisor");
if (IS_ERR(ptr)) {
rc = PTR_ERR(ptr);
goto err_out;
}
rc = 0;
err_out:
return rc;
}