s390/mm: allocate Absolute Lowcore Area in decompressor

Move Absolute Lowcore Area allocation to the decompressor.
As result, get_abs_lowcore() and put_abs_lowcore() access
brackets become really straight and do not require complex
execution context analysis and LAP and interrupts tackling.

Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
This commit is contained in:
Alexander Gordeev 2022-12-19 21:08:27 +01:00 committed by Heiko Carstens
parent 8e9205d2a5
commit 2154e0b328
10 changed files with 36 additions and 75 deletions

View File

@ -66,5 +66,7 @@ extern unsigned char _compressed_end[];
extern struct vmlinux_info _vmlinux_info;
#define vmlinux _vmlinux_info
#define __abs_lowcore_pa(x) (((unsigned long)(x) - __abs_lowcore) % sizeof(struct lowcore))
#endif /* __ASSEMBLY__ */
#endif /* BOOT_BOOT_H */

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@ -6,6 +6,7 @@
#include <asm/sections.h>
#include <asm/mem_detect.h>
#include <asm/maccess.h>
#include <asm/abs_lowcore.h>
#include "decompressor.h"
#include "boot.h"
@ -29,6 +30,7 @@ unsigned long __bootdata(pgalloc_low);
enum populate_mode {
POPULATE_NONE,
POPULATE_ONE2ONE,
POPULATE_ABS_LOWCORE,
};
static void boot_check_oom(void)
@ -102,6 +104,8 @@ static unsigned long _pa(unsigned long addr, enum populate_mode mode)
return -1;
case POPULATE_ONE2ONE:
return addr;
case POPULATE_ABS_LOWCORE:
return __abs_lowcore_pa(addr);
default:
return -1;
}
@ -271,6 +275,8 @@ void setup_vmem(unsigned long online_end, unsigned long asce_limit)
pgtable_populate_begin(online_end);
pgtable_populate(0, sizeof(struct lowcore), POPULATE_ONE2ONE);
pgtable_populate(0, online_end, POPULATE_ONE2ONE);
pgtable_populate(__abs_lowcore, __abs_lowcore + sizeof(struct lowcore),
POPULATE_ABS_LOWCORE);
pgtable_populate(__memcpy_real_area, __memcpy_real_area + PAGE_SIZE,
POPULATE_NONE);
memcpy_real_ptep = __virt_to_kpte(__memcpy_real_area);

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@ -7,11 +7,21 @@
#define ABS_LOWCORE_MAP_SIZE (NR_CPUS * sizeof(struct lowcore))
extern unsigned long __abs_lowcore;
extern bool abs_lowcore_mapped;
struct lowcore *get_abs_lowcore(unsigned long *flags);
void put_abs_lowcore(struct lowcore *lc, unsigned long flags);
int abs_lowcore_map(int cpu, struct lowcore *lc, bool alloc);
void abs_lowcore_unmap(int cpu);
static inline struct lowcore *get_abs_lowcore(void)
{
int cpu;
cpu = get_cpu();
return ((struct lowcore *)__abs_lowcore) + cpu;
}
static inline void put_abs_lowcore(struct lowcore *lc)
{
put_cpu();
}
#endif /* _ASM_S390_ABS_LOWCORE_H */

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@ -3,12 +3,7 @@
#include <linux/pgtable.h>
#include <asm/abs_lowcore.h>
#define ABS_LOWCORE_UNMAPPED 1
#define ABS_LOWCORE_LAP_ON 2
#define ABS_LOWCORE_IRQS_ON 4
unsigned long __bootdata_preserved(__abs_lowcore);
bool __ro_after_init abs_lowcore_mapped;
int abs_lowcore_map(int cpu, struct lowcore *lc, bool alloc)
{
@ -49,47 +44,3 @@ void abs_lowcore_unmap(int cpu)
addr += PAGE_SIZE;
}
}
struct lowcore *get_abs_lowcore(unsigned long *flags)
{
unsigned long irq_flags;
union ctlreg0 cr0;
int cpu;
*flags = 0;
cpu = get_cpu();
if (abs_lowcore_mapped) {
return ((struct lowcore *)__abs_lowcore) + cpu;
} else {
if (cpu != 0)
panic("Invalid unmapped absolute lowcore access\n");
local_irq_save(irq_flags);
if (!irqs_disabled_flags(irq_flags))
*flags |= ABS_LOWCORE_IRQS_ON;
__ctl_store(cr0.val, 0, 0);
if (cr0.lap) {
*flags |= ABS_LOWCORE_LAP_ON;
__ctl_clear_bit(0, 28);
}
*flags |= ABS_LOWCORE_UNMAPPED;
return lowcore_ptr[0];
}
}
void put_abs_lowcore(struct lowcore *lc, unsigned long flags)
{
if (abs_lowcore_mapped) {
if (flags)
panic("Invalid mapped absolute lowcore release\n");
} else {
if (smp_processor_id() != 0)
panic("Invalid mapped absolute lowcore access\n");
if (!(flags & ABS_LOWCORE_UNMAPPED))
panic("Invalid unmapped absolute lowcore release\n");
if (flags & ABS_LOWCORE_LAP_ON)
__ctl_set_bit(0, 28);
if (flags & ABS_LOWCORE_IRQS_ON)
local_irq_enable();
}
put_cpu();
}

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@ -1986,15 +1986,14 @@ static void dump_reipl_run(struct shutdown_trigger *trigger)
{
unsigned long ipib = (unsigned long) reipl_block_actual;
struct lowcore *abs_lc;
unsigned long flags;
unsigned int csum;
csum = (__force unsigned int)
csum_partial(reipl_block_actual, reipl_block_actual->hdr.len, 0);
abs_lc = get_abs_lowcore(&flags);
abs_lc = get_abs_lowcore();
abs_lc->ipib = ipib;
abs_lc->ipib_checksum = csum;
put_abs_lowcore(abs_lc, flags);
put_abs_lowcore(abs_lc);
dump_run(trigger);
}

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@ -224,7 +224,6 @@ void machine_kexec_cleanup(struct kimage *image)
void arch_crash_save_vmcoreinfo(void)
{
struct lowcore *abs_lc;
unsigned long flags;
VMCOREINFO_SYMBOL(lowcore_ptr);
VMCOREINFO_SYMBOL(high_memory);
@ -232,9 +231,9 @@ void arch_crash_save_vmcoreinfo(void)
vmcoreinfo_append_str("SAMODE31=%lx\n", __samode31);
vmcoreinfo_append_str("EAMODE31=%lx\n", __eamode31);
vmcoreinfo_append_str("KERNELOFFSET=%lx\n", kaslr_offset());
abs_lc = get_abs_lowcore(&flags);
abs_lc = get_abs_lowcore();
abs_lc->vmcore_info = paddr_vmcoreinfo_note();
put_abs_lowcore(abs_lc, flags);
put_abs_lowcore(abs_lc);
}
void machine_shutdown(void)

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@ -59,15 +59,14 @@ void os_info_entry_add(int nr, void *ptr, u64 size)
void __init os_info_init(void)
{
struct lowcore *abs_lc;
unsigned long flags;
os_info.version_major = OS_INFO_VERSION_MAJOR;
os_info.version_minor = OS_INFO_VERSION_MINOR;
os_info.magic = OS_INFO_MAGIC;
os_info.csum = os_info_csum(&os_info);
abs_lc = get_abs_lowcore(&flags);
abs_lc = get_abs_lowcore();
abs_lc->os_info = __pa(&os_info);
put_abs_lowcore(abs_lc, flags);
put_abs_lowcore(abs_lc);
}
#ifdef CONFIG_CRASH_DUMP

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@ -418,7 +418,6 @@ static void __init setup_lowcore(void)
{
struct lowcore *lc, *abs_lc;
unsigned long mcck_stack;
unsigned long flags;
/*
* Setup lowcore for boot cpu
@ -493,7 +492,7 @@ static void __init setup_lowcore(void)
lc->kernel_asce = S390_lowcore.kernel_asce;
lc->user_asce = S390_lowcore.user_asce;
abs_lc = get_abs_lowcore(&flags);
abs_lc = get_abs_lowcore();
abs_lc->restart_stack = lc->restart_stack;
abs_lc->restart_fn = lc->restart_fn;
abs_lc->restart_data = lc->restart_data;
@ -503,13 +502,12 @@ static void __init setup_lowcore(void)
memcpy(abs_lc->cregs_save_area, lc->cregs_save_area, sizeof(abs_lc->cregs_save_area));
abs_lc->program_new_psw = lc->program_new_psw;
abs_lc->mcesad = lc->mcesad;
put_abs_lowcore(abs_lc, flags);
put_abs_lowcore(abs_lc);
set_prefix(__pa(lc));
lowcore_ptr[0] = lc;
if (abs_lowcore_map(0, lowcore_ptr[0], true))
if (abs_lowcore_map(0, lowcore_ptr[0], false))
panic("Couldn't setup absolute lowcore");
abs_lowcore_mapped = true;
}
static struct resource code_resource = {

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@ -323,7 +323,6 @@ static void pcpu_delegate(struct pcpu *pcpu,
{
struct lowcore *lc, *abs_lc;
unsigned int source_cpu;
unsigned long flags;
lc = lowcore_ptr[pcpu - pcpu_devices];
source_cpu = stap();
@ -341,12 +340,12 @@ static void pcpu_delegate(struct pcpu *pcpu,
lc->restart_data = (unsigned long)data;
lc->restart_source = source_cpu;
} else {
abs_lc = get_abs_lowcore(&flags);
abs_lc = get_abs_lowcore();
abs_lc->restart_stack = stack;
abs_lc->restart_fn = (unsigned long)func;
abs_lc->restart_data = (unsigned long)data;
abs_lc->restart_source = source_cpu;
put_abs_lowcore(abs_lc, flags);
put_abs_lowcore(abs_lc);
}
__bpon();
asm volatile(
@ -593,7 +592,6 @@ void smp_ctl_set_clear_bit(int cr, int bit, bool set)
{
struct ec_creg_mask_parms parms = { .cr = cr, };
struct lowcore *abs_lc;
unsigned long flags;
u64 ctlreg;
if (set) {
@ -604,11 +602,11 @@ void smp_ctl_set_clear_bit(int cr, int bit, bool set)
parms.andval = ~(1UL << bit);
}
spin_lock(&ctl_lock);
abs_lc = get_abs_lowcore(&flags);
abs_lc = get_abs_lowcore();
ctlreg = abs_lc->cregs_save_area[cr];
ctlreg = (ctlreg & parms.andval) | parms.orval;
abs_lc->cregs_save_area[cr] = ctlreg;
put_abs_lowcore(abs_lc, flags);
put_abs_lowcore(abs_lc);
spin_unlock(&ctl_lock);
on_each_cpu(smp_ctl_bit_callback, &parms, 1);
}

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@ -151,7 +151,6 @@ void *xlate_dev_mem_ptr(phys_addr_t addr)
void *ptr = phys_to_virt(addr);
void *bounce = ptr;
struct lowcore *abs_lc;
unsigned long flags;
unsigned long size;
int this_cpu, cpu;
@ -167,10 +166,10 @@ void *xlate_dev_mem_ptr(phys_addr_t addr)
goto out;
size = PAGE_SIZE - (addr & ~PAGE_MASK);
if (addr < sizeof(struct lowcore)) {
abs_lc = get_abs_lowcore(&flags);
abs_lc = get_abs_lowcore();
ptr = (void *)abs_lc + addr;
memcpy(bounce, ptr, size);
put_abs_lowcore(abs_lc, flags);
put_abs_lowcore(abs_lc);
} else if (cpu == this_cpu) {
ptr = (void *)(addr - virt_to_phys(lowcore_ptr[cpu]));
memcpy(bounce, ptr, size);