[GitHub/moto-9609/android_kernel_motorola_exynos9610.git] / include / linux / dax.h

#ifndef _LINUX_DAX_H
#define _LINUX_DAX_H

#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/radix-tree.h>
#include <asm/pgtable.h>

struct iomap_ops;
struct dax_device;
struct dax_operations {
	/*
	 * direct_access: translate a device-relative
	 * logical-page-offset into an absolute physical pfn. Return the
	 * number of pages available for DAX at that pfn.
	 */
	long (*direct_access)(struct dax_device *, pgoff_t, long,
			void **, pfn_t *);
	/* copy_from_iter: required operation for fs-dax direct-i/o */
	size_t (*copy_from_iter)(struct dax_device *, pgoff_t, void *, size_t,
			struct iov_iter *);
	/* flush: optional driver-specific cache management after writes */
	void (*flush)(struct dax_device *, pgoff_t, void *, size_t);
};

extern struct attribute_group dax_attribute_group;

#if IS_ENABLED(CONFIG_DAX)
struct dax_device *dax_get_by_host(const char *host);
void put_dax(struct dax_device *dax_dev);
#else
static inline struct dax_device *dax_get_by_host(const char *host)
{
	return NULL;
}

static inline void put_dax(struct dax_device *dax_dev)
{
}
#endif

int bdev_dax_pgoff(struct block_device *, sector_t, size_t, pgoff_t *pgoff);
#if IS_ENABLED(CONFIG_FS_DAX)
int __bdev_dax_supported(struct super_block *sb, int blocksize);
static inline int bdev_dax_supported(struct super_block *sb, int blocksize)
{
	return __bdev_dax_supported(sb, blocksize);
}

static inline struct dax_device *fs_dax_get_by_host(const char *host)
{
	return dax_get_by_host(host);
}

static inline void fs_put_dax(struct dax_device *dax_dev)
{
	put_dax(dax_dev);
}

#else
static inline int bdev_dax_supported(struct super_block *sb, int blocksize)
{
	return -EOPNOTSUPP;
}

static inline struct dax_device *fs_dax_get_by_host(const char *host)
{
	return NULL;
}

static inline void fs_put_dax(struct dax_device *dax_dev)
{
}
#endif

int dax_read_lock(void);
void dax_read_unlock(int id);
struct dax_device *alloc_dax(void *private, const char *host,
		const struct dax_operations *ops);
bool dax_alive(struct dax_device *dax_dev);
void kill_dax(struct dax_device *dax_dev);
void *dax_get_private(struct dax_device *dax_dev);
long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages,
		void **kaddr, pfn_t *pfn);
size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
		size_t bytes, struct iov_iter *i);
void dax_flush(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
		size_t size);
void dax_write_cache(struct dax_device *dax_dev, bool wc);
bool dax_write_cache_enabled(struct dax_device *dax_dev);

/*
 * We use lowest available bit in exceptional entry for locking, one bit for
 * the entry size (PMD) and two more to tell us if the entry is a huge zero
 * page (HZP) or an empty entry that is just used for locking.  In total four
 * special bits.
 *
 * If the PMD bit isn't set the entry has size PAGE_SIZE, and if the HZP and
 * EMPTY bits aren't set the entry is a normal DAX entry with a filesystem
 * block allocation.
 */
#define RADIX_DAX_SHIFT	(RADIX_TREE_EXCEPTIONAL_SHIFT + 4)
#define RADIX_DAX_ENTRY_LOCK (1 << RADIX_TREE_EXCEPTIONAL_SHIFT)
#define RADIX_DAX_PMD (1 << (RADIX_TREE_EXCEPTIONAL_SHIFT + 1))
#define RADIX_DAX_HZP (1 << (RADIX_TREE_EXCEPTIONAL_SHIFT + 2))
#define RADIX_DAX_EMPTY (1 << (RADIX_TREE_EXCEPTIONAL_SHIFT + 3))

static inline unsigned long dax_radix_sector(void *entry)
{
	return (unsigned long)entry >> RADIX_DAX_SHIFT;
}

static inline void *dax_radix_locked_entry(sector_t sector, unsigned long flags)
{
	return (void *)(RADIX_TREE_EXCEPTIONAL_ENTRY | flags |
			((unsigned long)sector << RADIX_DAX_SHIFT) |
			RADIX_DAX_ENTRY_LOCK);
}

ssize_t dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter,
		const struct iomap_ops *ops);
int dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
		    const struct iomap_ops *ops);
int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index);
int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
				      pgoff_t index);
void dax_wake_mapping_entry_waiter(struct address_space *mapping,
		pgoff_t index, void *entry, bool wake_all);

#ifdef CONFIG_FS_DAX
int __dax_zero_page_range(struct block_device *bdev,
		struct dax_device *dax_dev, sector_t sector,
		unsigned int offset, unsigned int length);
#else
static inline int __dax_zero_page_range(struct block_device *bdev,
		struct dax_device *dax_dev, sector_t sector,
		unsigned int offset, unsigned int length)
{
	return -ENXIO;
}
#endif

#ifdef CONFIG_FS_DAX_PMD
static inline unsigned int dax_radix_order(void *entry)
{
	if ((unsigned long)entry & RADIX_DAX_PMD)
		return PMD_SHIFT - PAGE_SHIFT;
	return 0;
}
#else
static inline unsigned int dax_radix_order(void *entry)
{
	return 0;
}
#endif
int dax_pfn_mkwrite(struct vm_fault *vmf);

static inline bool dax_mapping(struct address_space *mapping)
{
	return mapping->host && IS_DAX(mapping->host);
}

struct writeback_control;
int dax_writeback_mapping_range(struct address_space *mapping,
		struct block_device *bdev, struct writeback_control *wbc);
#endif
Commit	Line	Data
c94c2acf MW	1	#ifndef _LINUX_DAX_H
	2	#define _LINUX_DAX_H
	3
	4	#include <linux/fs.h>
	5	#include <linux/mm.h>
4f622938	6	#include <linux/radix-tree.h>
c94c2acf MW	7	#include <asm/pgtable.h>
c94c2acf MW	8
a254e568	9	struct iomap_ops;
6568b08b DW	10	struct dax_device;
	11	struct dax_operations {
	12	/*
	13	* direct_access: translate a device-relative
	14	* logical-page-offset into an absolute physical pfn. Return the
	15	* number of pages available for DAX at that pfn.
	16	*/
	17	long (direct_access)(struct dax_device , pgoff_t, long,
	18	void *, pfn_t );
5d61e43b	19	/* copy_from_iter: required operation for fs-dax direct-i/o */
0aed55af DW	20	size_t (copy_from_iter)(struct dax_device , pgoff_t, void *, size_t,
0aed55af DW	21	struct iov_iter *);
3c1cebff DW	22	/* flush: optional driver-specific cache management after writes */
3c1cebff DW	23	void (flush)(struct dax_device , pgoff_t, void *, size_t);
6568b08b	24	};
a254e568	25
6e0c90d6 DW	26	extern struct attribute_group dax_attribute_group;
6e0c90d6 DW	27
f5705aa8 DW	28	#if IS_ENABLED(CONFIG_DAX)
	29	struct dax_device dax_get_by_host(const char host);
	30	void put_dax(struct dax_device *dax_dev);
	31	#else
	32	static inline struct dax_device dax_get_by_host(const char host)
	33	{
	34	return NULL;
	35	}
	36
	37	static inline void put_dax(struct dax_device *dax_dev)
	38	{
	39	}
	40	#endif
	41
ef510424 DW	42	int bdev_dax_pgoff(struct block_device , sector_t, size_t, pgoff_t pgoff);
	43	#if IS_ENABLED(CONFIG_FS_DAX)
	44	int __bdev_dax_supported(struct super_block *sb, int blocksize);
	45	static inline int bdev_dax_supported(struct super_block *sb, int blocksize)
	46	{
	47	return __bdev_dax_supported(sb, blocksize);
	48	}
f5705aa8 DW	49
	50	static inline struct dax_device fs_dax_get_by_host(const char host)
	51	{
	52	return dax_get_by_host(host);
	53	}
	54
	55	static inline void fs_put_dax(struct dax_device *dax_dev)
	56	{
	57	put_dax(dax_dev);
	58	}
	59
ef510424 DW	60	#else
	61	static inline int bdev_dax_supported(struct super_block *sb, int blocksize)
	62	{
	63	return -EOPNOTSUPP;
	64	}
ef510424	65
f5705aa8	66	static inline struct dax_device fs_dax_get_by_host(const char host)
ef510424 DW	67	{
	68	return NULL;
	69	}
	70
f5705aa8	71	static inline void fs_put_dax(struct dax_device *dax_dev)
ef510424 DW	72	{
	73	}
	74	#endif
	75
7b6be844 DW	76	int dax_read_lock(void);
7b6be844 DW	77	void dax_read_unlock(int id);
c1d6e828 DW	78	struct dax_device alloc_dax(void private, const char *host,
c1d6e828 DW	79	const struct dax_operations *ops);
c1d6e828 DW	80	bool dax_alive(struct dax_device *dax_dev);
	81	void kill_dax(struct dax_device *dax_dev);
	82	void dax_get_private(struct dax_device dax_dev);
b0686260 DW	83	long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages,
b0686260 DW	84	void *kaddr, pfn_t pfn);
7e026c8c DW	85	size_t dax_copy_from_iter(struct dax_device dax_dev, pgoff_t pgoff, void addr,
7e026c8c DW	86	size_t bytes, struct iov_iter *i);
abebfbe2 DW	87	void dax_flush(struct dax_device dax_dev, pgoff_t pgoff, void addr,
abebfbe2 DW	88	size_t size);
6e0c90d6	89	void dax_write_cache(struct dax_device *dax_dev, bool wc);
273752c9	90	bool dax_write_cache_enabled(struct dax_device *dax_dev);
7b6be844	91
fa28f729	92	/*
642261ac RZ	93	* We use lowest available bit in exceptional entry for locking, one bit for
	94	* the entry size (PMD) and two more to tell us if the entry is a huge zero
	95	* page (HZP) or an empty entry that is just used for locking. In total four
	96	* special bits.
	97	*
	98	* If the PMD bit isn't set the entry has size PAGE_SIZE, and if the HZP and
	99	* EMPTY bits aren't set the entry is a normal DAX entry with a filesystem
	100	* block allocation.
fa28f729	101	*/
642261ac	102	#define RADIX_DAX_SHIFT (RADIX_TREE_EXCEPTIONAL_SHIFT + 4)
e804315d	103	#define RADIX_DAX_ENTRY_LOCK (1 << RADIX_TREE_EXCEPTIONAL_SHIFT)
642261ac RZ	104	#define RADIX_DAX_PMD (1 << (RADIX_TREE_EXCEPTIONAL_SHIFT + 1))
	105	#define RADIX_DAX_HZP (1 << (RADIX_TREE_EXCEPTIONAL_SHIFT + 2))
	106	#define RADIX_DAX_EMPTY (1 << (RADIX_TREE_EXCEPTIONAL_SHIFT + 3))
fa28f729	107
642261ac RZ	108	static inline unsigned long dax_radix_sector(void *entry)
	109	{
	110	return (unsigned long)entry >> RADIX_DAX_SHIFT;
	111	}
	112
	113	static inline void *dax_radix_locked_entry(sector_t sector, unsigned long flags)
	114	{
	115	return (void *)(RADIX_TREE_EXCEPTIONAL_ENTRY \| flags \|
	116	((unsigned long)sector << RADIX_DAX_SHIFT) \|
	117	RADIX_DAX_ENTRY_LOCK);
	118	}
e804315d	119
11c59c92	120	ssize_t dax_iomap_rw(struct kiocb iocb, struct iov_iter iter,
8ff6daa1	121	const struct iomap_ops *ops);
c791ace1 DJ	122	int dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
c791ace1 DJ	123	const struct iomap_ops *ops);
ac401cc7	124	int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index);
c6dcf52c JK	125	int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
c6dcf52c JK	126	pgoff_t index);
ac401cc7	127	void dax_wake_mapping_entry_waiter(struct address_space *mapping,
63e95b5c	128	pgoff_t index, void *entry, bool wake_all);
d1a5f2b4 DW	129
d1a5f2b4 DW	130	#ifdef CONFIG_FS_DAX
cccbce67 DW	131	int __dax_zero_page_range(struct block_device *bdev,
cccbce67 DW	132	struct dax_device *dax_dev, sector_t sector,
679c8bd3	133	unsigned int offset, unsigned int length);
d1a5f2b4	134	#else
679c8bd3	135	static inline int __dax_zero_page_range(struct block_device *bdev,
cccbce67 DW	136	struct dax_device *dax_dev, sector_t sector,
cccbce67 DW	137	unsigned int offset, unsigned int length)
679c8bd3 CH	138	{
	139	return -ENXIO;
	140	}
d1a5f2b4 DW	141	#endif
d1a5f2b4 DW	142
642261ac RZ	143	#ifdef CONFIG_FS_DAX_PMD
	144	static inline unsigned int dax_radix_order(void *entry)
	145	{
	146	if ((unsigned long)entry & RADIX_DAX_PMD)
	147	return PMD_SHIFT - PAGE_SHIFT;
	148	return 0;
	149	}
642261ac RZ	150	#else
	151	static inline unsigned int dax_radix_order(void *entry)
	152	{
	153	return 0;
	154	}
642261ac	155	#endif
11bac800	156	int dax_pfn_mkwrite(struct vm_fault *vmf);
c94c2acf	157
f9fe48be RZ	158	static inline bool dax_mapping(struct address_space *mapping)
	159	{
	160	return mapping->host && IS_DAX(mapping->host);
	161	}
7f6d5b52 RZ	162
	163	struct writeback_control;
	164	int dax_writeback_mapping_range(struct address_space *mapping,
	165	struct block_device bdev, struct writeback_control wbc);
c94c2acf	166	#endif