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Release 4.14 arch/s390/kvm/sthyi.c

Directory: arch/s390/kvm
/*
 * store hypervisor information instruction emulation functions.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License (version 2 only)
 * as published by the Free Software Foundation.
 *
 * Copyright IBM Corp. 2016
 * Author(s): Janosch Frank <frankja@linux.vnet.ibm.com>
 */
#include <linux/kvm_host.h>
#include <linux/errno.h>
#include <linux/pagemap.h>
#include <linux/vmalloc.h>
#include <linux/ratelimit.h>

#include <asm/kvm_host.h>
#include <asm/asm-offsets.h>
#include <asm/sclp.h>
#include <asm/diag.h>
#include <asm/sysinfo.h>
#include <asm/ebcdic.h>

#include "kvm-s390.h"
#include "gaccess.h"
#include "trace.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;
};


static inline u64 cpu_id(u8 ctidx, void *diag224_buf) { return *((u64 *)(diag224_buf + (ctidx + 1) * DIAG204_CPU_NAME_LEN)); }

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Janosch Frank34100.00%1100.00%
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/* * 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; }

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Janosch Frank18100.00%1100.00%
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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; }

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Janosch Frank99100.00%1100.00%
Total99100.00%1100.00%


static void fill_stsi_mac(struct sthyi_sctns *sctns, struct sysinfo_1_1_1 *sysinfo) { if (stsi(sysinfo, 1, 1, 1)) return; sclp_ocf_cpc_name_copy(sctns->mac.infmname); 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 | MAC_NAME_VLD; }

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Janosch Frank137100.00%1100.00%
Total137100.00%1100.00%


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; }

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Janosch Frank70100.00%1100.00%
Total70100.00%1100.00%


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); }

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Janosch Frank58100.00%1100.00%
Total58100.00%1100.00%


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; }

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Janosch Frank132100.00%1100.00%
Total132100.00%1100.00%

/* 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]; }

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Janosch Frank296100.00%1100.00%
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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(PAGE_SIZE * pages); 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); }

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Janosch Frank531100.00%2100.00%
Total531100.00%2100.00%


static int sthyi(u64 vaddr) { register u64 code asm("0") = 0; register u64 addr asm("2") = vaddr; int cc; asm volatile( ".insn rre,0xB2560000,%[code],%[addr]\n" "ipm %[cc]\n" "srl %[cc],28\n" : [cc] "=d" (cc) : [code] "d" (code), [addr] "a" (addr) : "3", "memory", "cc"); return cc; }

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Janosch Frank3797.37%150.00%
Heiko Carstens12.63%150.00%
Total38100.00%2100.00%


int handle_sthyi(struct kvm_vcpu *vcpu) { int reg1, reg2, r = 0; u64 code, addr, cc = 0; struct sthyi_sctns *sctns = NULL; if (!test_kvm_facility(vcpu->kvm, 74)) return kvm_s390_inject_program_int(vcpu, PGM_OPERATION); /* * STHYI requires extensive locking in the higher hypervisors * and is very computational/memory expensive. Therefore we * ratelimit the executions per VM. */ if (!__ratelimit(&vcpu->kvm->arch.sthyi_limit)) { kvm_s390_retry_instr(vcpu); return 0; } kvm_s390_get_regs_rre(vcpu, &reg1, &reg2); code = vcpu->run->s.regs.gprs[reg1]; addr = vcpu->run->s.regs.gprs[reg2]; vcpu->stat.instruction_sthyi++; VCPU_EVENT(vcpu, 3, "STHYI: fc: %llu addr: 0x%016llx", code, addr); trace_kvm_s390_handle_sthyi(vcpu, code, addr); if (reg1 == reg2 || reg1 & 1 || reg2 & 1) return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION); if (code & 0xffff) { cc = 3; goto out; } if (addr & ~PAGE_MASK) return kvm_s390_inject_program_int(vcpu, PGM_SPECIFICATION); sctns = (void *)get_zeroed_page(GFP_KERNEL); if (!sctns) return -ENOMEM; /* * If we are a guest, we don't want to emulate an emulated * instruction. We ask the hypervisor to provide the data. */ if (test_facility(74)) { cc = sthyi((u64)sctns); goto out; } fill_hdr(sctns); fill_stsi(sctns); fill_diag(sctns); out: if (!cc) { r = write_guest(vcpu, addr, reg2, sctns, PAGE_SIZE); if (r) { free_page((unsigned long)sctns); return kvm_s390_inject_prog_cond(vcpu, r); } } free_page((unsigned long)sctns); vcpu->run->s.regs.gprs[reg2 + 1] = cc ? 4 : 0; kvm_s390_set_psw_cc(vcpu, cc); return r; }

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Janosch Frank31389.94%250.00%
Christian Bornträger205.75%125.00%
Heiko Carstens154.31%125.00%
Total348100.00%4100.00%


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Janosch Frank213298.34%350.00%
Christian Bornträger200.92%116.67%
Heiko Carstens160.74%233.33%
Total2168100.00%6100.00%
Directory: arch/s390/kvm
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