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Release 4.15 arch/s390/kernel/sthyi.c

Directory: arch/s390/kernel
// 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)); }

Contributors

PersonTokensPropCommitsCommitProp
Janosch Frank34100.00%1100.00%
Total34100.00%1100.00%

/* * 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%
Total18100.00%1100.00%


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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PersonTokensPropCommitsCommitProp
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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PersonTokensPropCommitsCommitProp
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); }

Contributors

PersonTokensPropCommitsCommitProp
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%
Total296100.00%1100.00%


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); }

Contributors

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


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

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PersonTokensPropCommitsCommitProp
Janosch Frank3767.27%150.00%
QingFeng Hao1832.73%150.00%
Total55100.00%2100.00%


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; }

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PersonTokensPropCommitsCommitProp
Janosch Frank4667.65%133.33%
QingFeng Hao2232.35%266.67%
Total68100.00%3100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
QingFeng Hao53100.00%1100.00%
Total53100.00%1100.00%


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; }

Contributors

PersonTokensPropCommitsCommitProp
QingFeng Hao53100.00%1100.00%
Total53100.00%1100.00%

/* * 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; }

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QingFeng Hao87100.00%1100.00%
Total87100.00%1100.00%

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; }

Overall Contributors

PersonTokensPropCommitsCommitProp
Janosch Frank185181.51%228.57%
QingFeng Hao41818.41%342.86%
Martin Schwidefsky10.04%114.29%
Greg Kroah-Hartman10.04%114.29%
Total2271100.00%7100.00%
Directory: arch/s390/kernel
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