Staging
v0.7.0
v0.7.0
https://github.com/torvalds/linux
Tip revision: 80e78fcce86de0288793a0ef0f6acf37656ee4cf authored by Linus Torvalds on 11 September 2022, 20:22:01 UTC
Linux 6.0-rc5
Linux 6.0-rc5
Tip revision: 80e78fc
sthyi.c
// SPDX-License-Identifier: GPL-2.0
/*
* store hypervisor information instruction emulation functions.
*
* Copyright IBM Corp. 2016
* Author(s): Janosch Frank <frankja@linux.vnet.ibm.com>
*/
#include <linux/errno.h>
#include <linux/pagemap.h>
#include <linux/vmalloc.h>
#include <linux/syscalls.h>
#include <linux/mutex.h>
#include <asm/asm-offsets.h>
#include <asm/sclp.h>
#include <asm/diag.h>
#include <asm/sysinfo.h>
#include <asm/ebcdic.h>
#include <asm/facility.h>
#include <asm/sthyi.h>
#include "entry.h"
#define DED_WEIGHT 0xffff
/*
* CP and IFL as EBCDIC strings, SP/0x40 determines the end of string
* as they are justified with spaces.
*/
#define CP 0xc3d7404040404040UL
#define IFL 0xc9c6d34040404040UL
enum hdr_flags {
HDR_NOT_LPAR = 0x10,
HDR_STACK_INCM = 0x20,
HDR_STSI_UNAV = 0x40,
HDR_PERF_UNAV = 0x80,
};
enum mac_validity {
MAC_NAME_VLD = 0x20,
MAC_ID_VLD = 0x40,
MAC_CNT_VLD = 0x80,
};
enum par_flag {
PAR_MT_EN = 0x80,
};
enum par_validity {
PAR_GRP_VLD = 0x08,
PAR_ID_VLD = 0x10,
PAR_ABS_VLD = 0x20,
PAR_WGHT_VLD = 0x40,
PAR_PCNT_VLD = 0x80,
};
struct hdr_sctn {
u8 infhflg1;
u8 infhflg2; /* reserved */
u8 infhval1; /* reserved */
u8 infhval2; /* reserved */
u8 reserved[3];
u8 infhygct;
u16 infhtotl;
u16 infhdln;
u16 infmoff;
u16 infmlen;
u16 infpoff;
u16 infplen;
u16 infhoff1;
u16 infhlen1;
u16 infgoff1;
u16 infglen1;
u16 infhoff2;
u16 infhlen2;
u16 infgoff2;
u16 infglen2;
u16 infhoff3;
u16 infhlen3;
u16 infgoff3;
u16 infglen3;
u8 reserved2[4];
} __packed;
struct mac_sctn {
u8 infmflg1; /* reserved */
u8 infmflg2; /* reserved */
u8 infmval1;
u8 infmval2; /* reserved */
u16 infmscps;
u16 infmdcps;
u16 infmsifl;
u16 infmdifl;
char infmname[8];
char infmtype[4];
char infmmanu[16];
char infmseq[16];
char infmpman[4];
u8 reserved[4];
} __packed;
struct par_sctn {
u8 infpflg1;
u8 infpflg2; /* reserved */
u8 infpval1;
u8 infpval2; /* reserved */
u16 infppnum;
u16 infpscps;
u16 infpdcps;
u16 infpsifl;
u16 infpdifl;
u16 reserved;
char infppnam[8];
u32 infpwbcp;
u32 infpabcp;
u32 infpwbif;
u32 infpabif;
char infplgnm[8];
u32 infplgcp;
u32 infplgif;
} __packed;
struct sthyi_sctns {
struct hdr_sctn hdr;
struct mac_sctn mac;
struct par_sctn par;
} __packed;
struct cpu_inf {
u64 lpar_cap;
u64 lpar_grp_cap;
u64 lpar_weight;
u64 all_weight;
int cpu_num_ded;
int cpu_num_shd;
};
struct lpar_cpu_inf {
struct cpu_inf cp;
struct cpu_inf ifl;
};
/*
* STHYI requires extensive locking in the higher hypervisors
* and is very computational/memory expensive. Therefore we
* cache the retrieved data whose valid period is 1s.
*/
#define CACHE_VALID_JIFFIES HZ
struct sthyi_info {
void *info;
unsigned long end;
};
static DEFINE_MUTEX(sthyi_mutex);
static struct sthyi_info sthyi_cache;
static inline u64 cpu_id(u8 ctidx, void *diag224_buf)
{
return *((u64 *)(diag224_buf + (ctidx + 1) * DIAG204_CPU_NAME_LEN));
}
/*
* Scales the cpu capping from the lpar range to the one expected in
* sthyi data.
*
* diag204 reports a cap in hundredths of processor units.
* z/VM's range for one core is 0 - 0x10000.
*/
static u32 scale_cap(u32 in)
{
return (0x10000 * in) / 100;
}
static void fill_hdr(struct sthyi_sctns *sctns)
{
sctns->hdr.infhdln = sizeof(sctns->hdr);
sctns->hdr.infmoff = sizeof(sctns->hdr);
sctns->hdr.infmlen = sizeof(sctns->mac);
sctns->hdr.infplen = sizeof(sctns->par);
sctns->hdr.infpoff = sctns->hdr.infhdln + sctns->hdr.infmlen;
sctns->hdr.infhtotl = sctns->hdr.infpoff + sctns->hdr.infplen;
}
static void fill_stsi_mac(struct sthyi_sctns *sctns,
struct sysinfo_1_1_1 *sysinfo)
{
sclp_ocf_cpc_name_copy(sctns->mac.infmname);
if (*(u64 *)sctns->mac.infmname != 0)
sctns->mac.infmval1 |= MAC_NAME_VLD;
if (stsi(sysinfo, 1, 1, 1))
return;
memcpy(sctns->mac.infmtype, sysinfo->type, sizeof(sctns->mac.infmtype));
memcpy(sctns->mac.infmmanu, sysinfo->manufacturer, sizeof(sctns->mac.infmmanu));
memcpy(sctns->mac.infmpman, sysinfo->plant, sizeof(sctns->mac.infmpman));
memcpy(sctns->mac.infmseq, sysinfo->sequence, sizeof(sctns->mac.infmseq));
sctns->mac.infmval1 |= MAC_ID_VLD;
}
static void fill_stsi_par(struct sthyi_sctns *sctns,
struct sysinfo_2_2_2 *sysinfo)
{
if (stsi(sysinfo, 2, 2, 2))
return;
sctns->par.infppnum = sysinfo->lpar_number;
memcpy(sctns->par.infppnam, sysinfo->name, sizeof(sctns->par.infppnam));
sctns->par.infpval1 |= PAR_ID_VLD;
}
static void fill_stsi(struct sthyi_sctns *sctns)
{
void *sysinfo;
/* Errors are handled through the validity bits in the response. */
sysinfo = (void *)__get_free_page(GFP_KERNEL);
if (!sysinfo)
return;
fill_stsi_mac(sctns, sysinfo);
fill_stsi_par(sctns, sysinfo);
free_pages((unsigned long)sysinfo, 0);
}
static void fill_diag_mac(struct sthyi_sctns *sctns,
struct diag204_x_phys_block *block,
void *diag224_buf)
{
int i;
for (i = 0; i < block->hdr.cpus; i++) {
switch (cpu_id(block->cpus[i].ctidx, diag224_buf)) {
case CP:
if (block->cpus[i].weight == DED_WEIGHT)
sctns->mac.infmdcps++;
else
sctns->mac.infmscps++;
break;
case IFL:
if (block->cpus[i].weight == DED_WEIGHT)
sctns->mac.infmdifl++;
else
sctns->mac.infmsifl++;
break;
}
}
sctns->mac.infmval1 |= MAC_CNT_VLD;
}
/* Returns a pointer to the the next partition block. */
static struct diag204_x_part_block *lpar_cpu_inf(struct lpar_cpu_inf *part_inf,
bool this_lpar,
void *diag224_buf,
struct diag204_x_part_block *block)
{
int i, capped = 0, weight_cp = 0, weight_ifl = 0;
struct cpu_inf *cpu_inf;
for (i = 0; i < block->hdr.rcpus; i++) {
if (!(block->cpus[i].cflag & DIAG204_CPU_ONLINE))
continue;
switch (cpu_id(block->cpus[i].ctidx, diag224_buf)) {
case CP:
cpu_inf = &part_inf->cp;
if (block->cpus[i].cur_weight < DED_WEIGHT)
weight_cp |= block->cpus[i].cur_weight;
break;
case IFL:
cpu_inf = &part_inf->ifl;
if (block->cpus[i].cur_weight < DED_WEIGHT)
weight_ifl |= block->cpus[i].cur_weight;
break;
default:
continue;
}
if (!this_lpar)
continue;
capped |= block->cpus[i].cflag & DIAG204_CPU_CAPPED;
cpu_inf->lpar_cap |= block->cpus[i].cpu_type_cap;
cpu_inf->lpar_grp_cap |= block->cpus[i].group_cpu_type_cap;
if (block->cpus[i].weight == DED_WEIGHT)
cpu_inf->cpu_num_ded += 1;
else
cpu_inf->cpu_num_shd += 1;
}
if (this_lpar && capped) {
part_inf->cp.lpar_weight = weight_cp;
part_inf->ifl.lpar_weight = weight_ifl;
}
part_inf->cp.all_weight += weight_cp;
part_inf->ifl.all_weight += weight_ifl;
return (struct diag204_x_part_block *)&block->cpus[i];
}
static void fill_diag(struct sthyi_sctns *sctns)
{
int i, r, pages;
bool this_lpar;
void *diag204_buf;
void *diag224_buf = NULL;
struct diag204_x_info_blk_hdr *ti_hdr;
struct diag204_x_part_block *part_block;
struct diag204_x_phys_block *phys_block;
struct lpar_cpu_inf lpar_inf = {};
/* Errors are handled through the validity bits in the response. */
pages = diag204((unsigned long)DIAG204_SUBC_RSI |
(unsigned long)DIAG204_INFO_EXT, 0, NULL);
if (pages <= 0)
return;
diag204_buf = vmalloc(array_size(pages, PAGE_SIZE));
if (!diag204_buf)
return;
r = diag204((unsigned long)DIAG204_SUBC_STIB7 |
(unsigned long)DIAG204_INFO_EXT, pages, diag204_buf);
if (r < 0)
goto out;
diag224_buf = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
if (!diag224_buf || diag224(diag224_buf))
goto out;
ti_hdr = diag204_buf;
part_block = diag204_buf + sizeof(*ti_hdr);
for (i = 0; i < ti_hdr->npar; i++) {
/*
* For the calling lpar we also need to get the cpu
* caps and weights. The time information block header
* specifies the offset to the partition block of the
* caller lpar, so we know when we process its data.
*/
this_lpar = (void *)part_block - diag204_buf == ti_hdr->this_part;
part_block = lpar_cpu_inf(&lpar_inf, this_lpar, diag224_buf,
part_block);
}
phys_block = (struct diag204_x_phys_block *)part_block;
part_block = diag204_buf + ti_hdr->this_part;
if (part_block->hdr.mtid)
sctns->par.infpflg1 = PAR_MT_EN;
sctns->par.infpval1 |= PAR_GRP_VLD;
sctns->par.infplgcp = scale_cap(lpar_inf.cp.lpar_grp_cap);
sctns->par.infplgif = scale_cap(lpar_inf.ifl.lpar_grp_cap);
memcpy(sctns->par.infplgnm, part_block->hdr.hardware_group_name,
sizeof(sctns->par.infplgnm));
sctns->par.infpscps = lpar_inf.cp.cpu_num_shd;
sctns->par.infpdcps = lpar_inf.cp.cpu_num_ded;
sctns->par.infpsifl = lpar_inf.ifl.cpu_num_shd;
sctns->par.infpdifl = lpar_inf.ifl.cpu_num_ded;
sctns->par.infpval1 |= PAR_PCNT_VLD;
sctns->par.infpabcp = scale_cap(lpar_inf.cp.lpar_cap);
sctns->par.infpabif = scale_cap(lpar_inf.ifl.lpar_cap);
sctns->par.infpval1 |= PAR_ABS_VLD;
/*
* Everything below needs global performance data to be
* meaningful.
*/
if (!(ti_hdr->flags & DIAG204_LPAR_PHYS_FLG)) {
sctns->hdr.infhflg1 |= HDR_PERF_UNAV;
goto out;
}
fill_diag_mac(sctns, phys_block, diag224_buf);
if (lpar_inf.cp.lpar_weight) {
sctns->par.infpwbcp = sctns->mac.infmscps * 0x10000 *
lpar_inf.cp.lpar_weight / lpar_inf.cp.all_weight;
}
if (lpar_inf.ifl.lpar_weight) {
sctns->par.infpwbif = sctns->mac.infmsifl * 0x10000 *
lpar_inf.ifl.lpar_weight / lpar_inf.ifl.all_weight;
}
sctns->par.infpval1 |= PAR_WGHT_VLD;
out:
free_page((unsigned long)diag224_buf);
vfree(diag204_buf);
}
static int sthyi(u64 vaddr, u64 *rc)
{
union register_pair r1 = { .even = 0, }; /* subcode */
union register_pair r2 = { .even = vaddr, };
int cc;
asm volatile(
".insn rre,0xB2560000,%[r1],%[r2]\n"
"ipm %[cc]\n"
"srl %[cc],28\n"
: [cc] "=&d" (cc), [r2] "+&d" (r2.pair)
: [r1] "d" (r1.pair)
: "memory", "cc");
*rc = r2.odd;
return cc;
}
static int fill_dst(void *dst, u64 *rc)
{
struct sthyi_sctns *sctns = (struct sthyi_sctns *)dst;
/*
* If the facility is on, we don't want to emulate the instruction.
* We ask the hypervisor to provide the data.
*/
if (test_facility(74))
return sthyi((u64)dst, rc);
fill_hdr(sctns);
fill_stsi(sctns);
fill_diag(sctns);
*rc = 0;
return 0;
}
static int sthyi_init_cache(void)
{
if (sthyi_cache.info)
return 0;
sthyi_cache.info = (void *)get_zeroed_page(GFP_KERNEL);
if (!sthyi_cache.info)
return -ENOMEM;
sthyi_cache.end = jiffies - 1; /* expired */
return 0;
}
static int sthyi_update_cache(u64 *rc)
{
int r;
memset(sthyi_cache.info, 0, PAGE_SIZE);
r = fill_dst(sthyi_cache.info, rc);
if (r)
return r;
sthyi_cache.end = jiffies + CACHE_VALID_JIFFIES;
return r;
}
/*
* sthyi_fill - Fill page with data returned by the STHYI instruction
*
* @dst: Pointer to zeroed page
* @rc: Pointer for storing the return code of the instruction
*
* Fills the destination with system information returned by the STHYI
* instruction. The data is generated by emulation or execution of STHYI,
* if available. The return value is the condition code that would be
* returned, the rc parameter is the return code which is passed in
* register R2 + 1.
*/
int sthyi_fill(void *dst, u64 *rc)
{
int r;
mutex_lock(&sthyi_mutex);
r = sthyi_init_cache();
if (r)
goto out;
if (time_is_before_jiffies(sthyi_cache.end)) {
/* cache expired */
r = sthyi_update_cache(rc);
if (r)
goto out;
}
*rc = 0;
memcpy(dst, sthyi_cache.info, PAGE_SIZE);
out:
mutex_unlock(&sthyi_mutex);
return r;
}
EXPORT_SYMBOL_GPL(sthyi_fill);
SYSCALL_DEFINE4(s390_sthyi, unsigned long, function_code, void __user *, buffer,
u64 __user *, return_code, unsigned long, flags)
{
u64 sthyi_rc;
void *info;
int r;
if (flags)
return -EINVAL;
if (function_code != STHYI_FC_CP_IFL_CAP)
return -EOPNOTSUPP;
info = (void *)get_zeroed_page(GFP_KERNEL);
if (!info)
return -ENOMEM;
r = sthyi_fill(info, &sthyi_rc);
if (r < 0)
goto out;
if (return_code && put_user(sthyi_rc, return_code)) {
r = -EFAULT;
goto out;
}
if (copy_to_user(buffer, info, PAGE_SIZE))
r = -EFAULT;
out:
free_page((unsigned long)info);
return r;
}