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#ifndef _ASM_X86_CACHEFLUSH_H
#define _ASM_X86_CACHEFLUSH_H

/* Caches aren't brain-dead on the intel. */
#include <asm-generic/cacheflush.h>
#include <asm/special_insns.h>
#include <asm/uaccess.h>

#ifdef CONFIG_X86_PAT
/*
 * X86 PAT uses page flags WC and Uncached together to keep track of
 * memory type of pages that have backing page struct. X86 PAT supports 3
 * different memory types, _PAGE_CACHE_MODE_WB, _PAGE_CACHE_MODE_WC and
 * _PAGE_CACHE_MODE_UC_MINUS and fourth state where page's memory type has not
 * been changed from its default (value of -1 used to denote this).
 * Note we do not support _PAGE_CACHE_MODE_UC here.
 */

#define _PGMT_DEFAULT		0
#define _PGMT_WC		(1UL << PG_arch_1)
#define _PGMT_UC_MINUS		(1UL << PG_uncached)
#define _PGMT_WB		(1UL << PG_uncached | 1UL << PG_arch_1)
#define _PGMT_MASK		(1UL << PG_uncached | 1UL << PG_arch_1)
#define _PGMT_CLEAR_MASK	(~_PGMT_MASK)

static inline enum page_cache_mode get_page_memtype(struct page *pg)
{
	unsigned long pg_flags = pg->flags & _PGMT_MASK;

if (pg_flags == _PGMT_DEFAULT)
		return -1;
	else if (pg_flags == _PGMT_WC)
		return _PAGE_CACHE_MODE_WC;
	else if (pg_flags == _PGMT_UC_MINUS)
		return _PAGE_CACHE_MODE_UC_MINUS;
	else
		return _PAGE_CACHE_MODE_WB;
}

static inline void set_page_memtype(struct page *pg,
				    enum page_cache_mode memtype)
{
	unsigned long memtype_flags;
	unsigned long old_flags;
	unsigned long new_flags;

switch (memtype) {
	case _PAGE_CACHE_MODE_WC:
		memtype_flags = _PGMT_WC;
		break;
	case _PAGE_CACHE_MODE_UC_MINUS:
		memtype_flags = _PGMT_UC_MINUS;
		break;
	case _PAGE_CACHE_MODE_WB:
		memtype_flags = _PGMT_WB;
		break;
	default:
		memtype_flags = _PGMT_DEFAULT;
		break;
	}

do {
		old_flags = pg->flags;
		new_flags = (old_flags & _PGMT_CLEAR_MASK) | memtype_flags;
	} while (cmpxchg(&pg->flags, old_flags, new_flags) != old_flags);
}
#else
static inline enum page_cache_mode get_page_memtype(struct page *pg)
{
	return -1;
}
static inline void set_page_memtype(struct page *pg,
				    enum page_cache_mode memtype)
{
}
#endif

/*
 * The set_memory_* API can be used to change various attributes of a virtual
 * address range. The attributes include:
 * Cachability   : UnCached, WriteCombining, WriteBack
 * Executability : eXeutable, NoteXecutable
 * Read/Write    : ReadOnly, ReadWrite
 * Presence      : NotPresent
 * Encryption    : Encrypted, Decrypted
 *
 * Within a category, the attributes are mutually exclusive.
 *
 * The implementation of this API will take care of various aspects that
 * are associated with changing such attributes, such as:
 * - Flushing TLBs
 * - Flushing CPU caches
 * - Making sure aliases of the memory behind the mapping don't violate
 *   coherency rules as defined by the CPU in the system.
 *
 * What this API does not do:
 * - Provide exclusion between various callers - including callers that
 *   operation on other mappings of the same physical page
 * - Restore default attributes when a page is freed
 * - Guarantee that mappings other than the requested one are
 *   in any state, other than that these do not violate rules for
 *   the CPU you have. Do not depend on any effects on other mappings,
 *   CPUs other than the one you have may have more relaxed rules.
 * The caller is required to take care of these.
 */

int _set_memory_uc(unsigned long addr, int numpages);
int _set_memory_wc(unsigned long addr, int numpages);
int _set_memory_wb(unsigned long addr, int numpages);
int set_memory_uc(unsigned long addr, int numpages);
int set_memory_wc(unsigned long addr, int numpages);
int set_memory_wb(unsigned long addr, int numpages);
int set_memory_x(unsigned long addr, int numpages);
int set_memory_nx(unsigned long addr, int numpages);
int set_memory_ro(unsigned long addr, int numpages);
int set_memory_rw(unsigned long addr, int numpages);
int set_memory_np(unsigned long addr, int numpages);
int set_memory_4k(unsigned long addr, int numpages);
int set_memory_encrypted(unsigned long addr, int numpages);
int set_memory_decrypted(unsigned long addr, int numpages);

int set_memory_array_uc(unsigned long *addr, int addrinarray);
int set_memory_array_wc(unsigned long *addr, int addrinarray);
int set_memory_array_wb(unsigned long *addr, int addrinarray);

int set_pages_array_uc(struct page **pages, int addrinarray);
int set_pages_array_wc(struct page **pages, int addrinarray);
int set_pages_array_wb(struct page **pages, int addrinarray);

/*
 * For legacy compatibility with the old APIs, a few functions
 * are provided that work on a "struct page".
 * These functions operate ONLY on the 1:1 kernel mapping of the
 * memory that the struct page represents, and internally just
 * call the set_memory_* function. See the description of the
 * set_memory_* function for more details on conventions.
 *
 * These APIs should be considered *deprecated* and are likely going to
 * be removed in the future.
 * The reason for this is the implicit operation on the 1:1 mapping only,
 * making this not a generally useful API.
 *
 * Specifically, many users of the old APIs had a virtual address,
 * called virt_to_page() or vmalloc_to_page() on that address to
 * get a struct page* that the old API required.
 * To convert these cases, use set_memory_*() on the original
 * virtual address, do not use these functions.
 */

int set_pages_uc(struct page *page, int numpages);
int set_pages_wb(struct page *page, int numpages);
int set_pages_x(struct page *page, int numpages);
int set_pages_nx(struct page *page, int numpages);
int set_pages_ro(struct page *page, int numpages);
int set_pages_rw(struct page *page, int numpages);

void clflush_cache_range(void *addr, unsigned int size);

#define mmio_flush_range(addr, size) clflush_cache_range(addr, size)

#ifdef CONFIG_DEBUG_RODATA
void mark_rodata_ro(void);
extern const int rodata_test_data;
extern int kernel_set_to_readonly;
void set_kernel_text_rw(void);
void set_kernel_text_ro(void);
#else
static inline void set_kernel_text_rw(void) { }
static inline void set_kernel_text_ro(void) { }
#endif

#ifdef CONFIG_X86_64
static inline int set_mce_nospec(unsigned long pfn)
{
	unsigned long decoy_addr;
	int rc;

/*
	 * Mark the linear address as UC to make sure we don't log more
	 * errors because of speculative access to the page.
	 * We would like to just call:
	 *      set_memory_uc((unsigned long)pfn_to_kaddr(pfn), 1);
	 * but doing that would radically increase the odds of a
	 * speculative access to the poison page because we'd have
	 * the virtual address of the kernel 1:1 mapping sitting
	 * around in registers.
	 * Instead we get tricky.  We create a non-canonical address
	 * that looks just like the one we want, but has bit 63 flipped.
	 * This relies on set_memory_uc() properly sanitizing any __pa()
	 * results with __PHYSICAL_MASK or PTE_PFN_MASK.
	 */
	decoy_addr = (pfn << PAGE_SHIFT) + (PAGE_OFFSET ^ BIT(63));

rc = set_memory_uc(decoy_addr, 1);
	if (rc)
		printk(KERN_WARNING
		       "Could not invalidate pfn=0x%lx from 1:1 map\n", pfn);
	return rc;
}
#define set_mce_nospec set_mce_nospec

/* Restore full speculative operation to the pfn. */
static inline int clear_mce_nospec(unsigned long pfn)
{
	return set_memory_wb((unsigned long) pfn_to_kaddr(pfn), 1);
}
#define clear_mce_nospec clear_mce_nospec
#else
/*
 * Few people would run a 32-bit kernel on a machine that supports
 * recoverable errors because they have too much memory to boot 32-bit.
 */
#endif

#ifdef CONFIG_DEBUG_RODATA_TEST
int rodata_test(void);
#else
static inline int rodata_test(void)
{
	return 0;
}
#endif

#endif /* _ASM_X86_CACHEFLUSH_H */

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