linux_dsm_epyc7002/arch/s390/include/asm/mem_detect.h
Vasily Gorbik 9b692102d8 s390/mem_detect: provide single get_mem_detect_end
get_mem_detect_end is already used in couple of places with potential
to be utilized in more cases. Provide single get_mem_detect_end
implementation in asm/mem_detect.h to be used by kasan and startup code.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2019-08-26 12:51:18 +02:00

95 lines
2.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_S390_MEM_DETECT_H
#define _ASM_S390_MEM_DETECT_H
#include <linux/types.h>
enum mem_info_source {
MEM_DETECT_NONE = 0,
MEM_DETECT_SCLP_STOR_INFO,
MEM_DETECT_DIAG260,
MEM_DETECT_SCLP_READ_INFO,
MEM_DETECT_BIN_SEARCH
};
struct mem_detect_block {
u64 start;
u64 end;
};
/*
* Storage element id is defined as 1 byte (up to 256 storage elements).
* In practise only storage element id 0 and 1 are used).
* According to architecture one storage element could have as much as
* 1020 subincrements. 255 mem_detect_blocks are embedded in mem_detect_info.
* If more mem_detect_blocks are required, a block of memory from already
* known mem_detect_block is taken (entries_extended points to it).
*/
#define MEM_INLINED_ENTRIES 255 /* (PAGE_SIZE - 16) / 16 */
struct mem_detect_info {
u32 count;
u8 info_source;
struct mem_detect_block entries[MEM_INLINED_ENTRIES];
struct mem_detect_block *entries_extended;
};
extern struct mem_detect_info mem_detect;
void add_mem_detect_block(u64 start, u64 end);
static inline int __get_mem_detect_block(u32 n, unsigned long *start,
unsigned long *end)
{
if (n >= mem_detect.count) {
*start = 0;
*end = 0;
return -1;
}
if (n < MEM_INLINED_ENTRIES) {
*start = (unsigned long)mem_detect.entries[n].start;
*end = (unsigned long)mem_detect.entries[n].end;
} else {
*start = (unsigned long)mem_detect.entries_extended[n - MEM_INLINED_ENTRIES].start;
*end = (unsigned long)mem_detect.entries_extended[n - MEM_INLINED_ENTRIES].end;
}
return 0;
}
/**
* for_each_mem_detect_block - early online memory range iterator
* @i: an integer used as loop variable
* @p_start: ptr to unsigned long for start address of the range
* @p_end: ptr to unsigned long for end address of the range
*
* Walks over detected online memory ranges.
*/
#define for_each_mem_detect_block(i, p_start, p_end) \
for (i = 0, __get_mem_detect_block(i, p_start, p_end); \
i < mem_detect.count; \
i++, __get_mem_detect_block(i, p_start, p_end))
static inline void get_mem_detect_reserved(unsigned long *start,
unsigned long *size)
{
*start = (unsigned long)mem_detect.entries_extended;
if (mem_detect.count > MEM_INLINED_ENTRIES)
*size = (mem_detect.count - MEM_INLINED_ENTRIES) * sizeof(struct mem_detect_block);
else
*size = 0;
}
static inline unsigned long get_mem_detect_end(void)
{
unsigned long start;
unsigned long end;
if (mem_detect.count) {
__get_mem_detect_block(mem_detect.count - 1, &start, &end);
return end;
}
return 0;
}
#endif