arch/xtensa/include/asm/highmem.h

Source file repositories/reference/linux-study-clean/arch/xtensa/include/asm/highmem.h

File Facts

System
Linux kernel
Corpus path
arch/xtensa/include/asm/highmem.h
Extension
.h
Size
2173 bytes
Lines
85
Domain
Architecture Layer
Bucket
arch/xtensa
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

#ifndef _XTENSA_HIGHMEM_H
#define _XTENSA_HIGHMEM_H

#ifdef CONFIG_HIGHMEM
#include <linux/wait.h>
#include <linux/pgtable.h>
#include <asm/cacheflush.h>
#include <asm/fixmap.h>

#define PKMAP_BASE		((FIXADDR_START -			\
				  (LAST_PKMAP + 1) * PAGE_SIZE) & PMD_MASK)
#define LAST_PKMAP		(PTRS_PER_PTE * DCACHE_N_COLORS)
#define LAST_PKMAP_MASK		(LAST_PKMAP - 1)
#define PKMAP_NR(virt)		(((virt) - PKMAP_BASE) >> PAGE_SHIFT)
#define PKMAP_ADDR(nr)		(PKMAP_BASE + ((nr) << PAGE_SHIFT))

#define kmap_prot		PAGE_KERNEL_EXEC

#if DCACHE_WAY_SIZE > PAGE_SIZE
#define get_pkmap_color get_pkmap_color
static inline int get_pkmap_color(const struct page *page)
{
	return DCACHE_ALIAS(page_to_phys(page));
}

extern unsigned int last_pkmap_nr_arr[];

static inline unsigned int get_next_pkmap_nr(unsigned int color)
{
	last_pkmap_nr_arr[color] =
		(last_pkmap_nr_arr[color] + DCACHE_N_COLORS) & LAST_PKMAP_MASK;
	return last_pkmap_nr_arr[color] + color;
}

static inline int no_more_pkmaps(unsigned int pkmap_nr, unsigned int color)
{
	return pkmap_nr < DCACHE_N_COLORS;
}

static inline int get_pkmap_entries_count(unsigned int color)
{
	return LAST_PKMAP / DCACHE_N_COLORS;
}

extern wait_queue_head_t pkmap_map_wait_arr[];

static inline wait_queue_head_t *get_pkmap_wait_queue_head(unsigned int color)
{
	return pkmap_map_wait_arr + color;
}

enum fixed_addresses kmap_local_map_idx(int type, unsigned long pfn);
#define arch_kmap_local_map_idx		kmap_local_map_idx

enum fixed_addresses kmap_local_unmap_idx(int type, unsigned long addr);
#define arch_kmap_local_unmap_idx	kmap_local_unmap_idx

#endif

extern pte_t *pkmap_page_table;

static inline void flush_cache_kmaps(void)
{
	flush_cache_all();
}

#define arch_kmap_local_post_unmap(vaddr)	\
	local_flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE)

void kmap_init(void);

#endif /* CONFIG_HIGHMEM */
#endif

Annotation

Implementation Notes