linux/arch/sparc/kernel/hvapi.c
Paul Gortmaker 066bcaca51 sparc: move symbol exporters to use export.h not module.h
Many of the core sparc kernel files are not modules, but just
including module.h for exporting symbols.  Now these files can
use the lighter footprint export.h for this role.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:30:53 -04:00

200 lines
4.4 KiB
C

/* hvapi.c: Hypervisor API management.
*
* Copyright (C) 2007 David S. Miller <davem@davemloft.net>
*/
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/init.h>
#include <asm/hypervisor.h>
#include <asm/oplib.h>
/* If the hypervisor indicates that the API setting
* calls are unsupported, by returning HV_EBADTRAP or
* HV_ENOTSUPPORTED, we assume that API groups with the
* PRE_API flag set are major 1 minor 0.
*/
struct api_info {
unsigned long group;
unsigned long major;
unsigned long minor;
unsigned int refcnt;
unsigned int flags;
#define FLAG_PRE_API 0x00000001
};
static struct api_info api_table[] = {
{ .group = HV_GRP_SUN4V, .flags = FLAG_PRE_API },
{ .group = HV_GRP_CORE, .flags = FLAG_PRE_API },
{ .group = HV_GRP_INTR, },
{ .group = HV_GRP_SOFT_STATE, },
{ .group = HV_GRP_TM, },
{ .group = HV_GRP_PCI, .flags = FLAG_PRE_API },
{ .group = HV_GRP_LDOM, },
{ .group = HV_GRP_SVC_CHAN, .flags = FLAG_PRE_API },
{ .group = HV_GRP_NCS, .flags = FLAG_PRE_API },
{ .group = HV_GRP_RNG, },
{ .group = HV_GRP_PBOOT, },
{ .group = HV_GRP_TPM, },
{ .group = HV_GRP_SDIO, },
{ .group = HV_GRP_SDIO_ERR, },
{ .group = HV_GRP_REBOOT_DATA, },
{ .group = HV_GRP_NIAG_PERF, .flags = FLAG_PRE_API },
{ .group = HV_GRP_FIRE_PERF, },
{ .group = HV_GRP_N2_CPU, },
{ .group = HV_GRP_NIU, },
{ .group = HV_GRP_VF_CPU, },
{ .group = HV_GRP_KT_CPU, },
{ .group = HV_GRP_DIAG, .flags = FLAG_PRE_API },
};
static DEFINE_SPINLOCK(hvapi_lock);
static struct api_info *__get_info(unsigned long group)
{
int i;
for (i = 0; i < ARRAY_SIZE(api_table); i++) {
if (api_table[i].group == group)
return &api_table[i];
}
return NULL;
}
static void __get_ref(struct api_info *p)
{
p->refcnt++;
}
static void __put_ref(struct api_info *p)
{
if (--p->refcnt == 0) {
unsigned long ignore;
sun4v_set_version(p->group, 0, 0, &ignore);
p->major = p->minor = 0;
}
}
/* Register a hypervisor API specification. It indicates the
* API group and desired major+minor.
*
* If an existing API registration exists '0' (success) will
* be returned if it is compatible with the one being registered.
* Otherwise a negative error code will be returned.
*
* Otherwise an attempt will be made to negotiate the requested
* API group/major/minor with the hypervisor, and errors returned
* if that does not succeed.
*/
int sun4v_hvapi_register(unsigned long group, unsigned long major,
unsigned long *minor)
{
struct api_info *p;
unsigned long flags;
int ret;
spin_lock_irqsave(&hvapi_lock, flags);
p = __get_info(group);
ret = -EINVAL;
if (p) {
if (p->refcnt) {
ret = -EINVAL;
if (p->major == major) {
*minor = p->minor;
ret = 0;
}
} else {
unsigned long actual_minor;
unsigned long hv_ret;
hv_ret = sun4v_set_version(group, major, *minor,
&actual_minor);
ret = -EINVAL;
if (hv_ret == HV_EOK) {
*minor = actual_minor;
p->major = major;
p->minor = actual_minor;
ret = 0;
} else if (hv_ret == HV_EBADTRAP ||
hv_ret == HV_ENOTSUPPORTED) {
if (p->flags & FLAG_PRE_API) {
if (major == 1) {
p->major = 1;
p->minor = 0;
*minor = 0;
ret = 0;
}
}
}
}
if (ret == 0)
__get_ref(p);
}
spin_unlock_irqrestore(&hvapi_lock, flags);
return ret;
}
EXPORT_SYMBOL(sun4v_hvapi_register);
void sun4v_hvapi_unregister(unsigned long group)
{
struct api_info *p;
unsigned long flags;
spin_lock_irqsave(&hvapi_lock, flags);
p = __get_info(group);
if (p)
__put_ref(p);
spin_unlock_irqrestore(&hvapi_lock, flags);
}
EXPORT_SYMBOL(sun4v_hvapi_unregister);
int sun4v_hvapi_get(unsigned long group,
unsigned long *major,
unsigned long *minor)
{
struct api_info *p;
unsigned long flags;
int ret;
spin_lock_irqsave(&hvapi_lock, flags);
ret = -EINVAL;
p = __get_info(group);
if (p && p->refcnt) {
*major = p->major;
*minor = p->minor;
ret = 0;
}
spin_unlock_irqrestore(&hvapi_lock, flags);
return ret;
}
EXPORT_SYMBOL(sun4v_hvapi_get);
void __init sun4v_hvapi_init(void)
{
unsigned long group, major, minor;
group = HV_GRP_SUN4V;
major = 1;
minor = 0;
if (sun4v_hvapi_register(group, major, &minor))
goto bad;
group = HV_GRP_CORE;
major = 1;
minor = 1;
if (sun4v_hvapi_register(group, major, &minor))
goto bad;
return;
bad:
prom_printf("HVAPI: Cannot register API group "
"%lx with major(%u) minor(%u)\n",
group, major, minor);
prom_halt();
}