[linux-block.git] / include / linux / dax.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_DAX_H
#define _LINUX_DAX_H

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

/* Flag for synchronous flush */
#define DAXDEV_F_SYNC (1UL << 0)

typedef unsigned long dax_entry_t;

struct iomap_ops;
struct iomap;
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 *);
	/*
	 * Validate whether this device is usable as an fsdax backing
	 * device.
	 */
	bool (*dax_supported)(struct dax_device *, struct block_device *, int,
			sector_t, sector_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 *);
	/* copy_to_iter: required operation for fs-dax direct-i/o */
	size_t (*copy_to_iter)(struct dax_device *, pgoff_t, void *, size_t,
			struct iov_iter *);
	/* zero_page_range: required operation. Zero page range   */
	int (*zero_page_range)(struct dax_device *, pgoff_t, size_t);
};

extern struct attribute_group dax_attribute_group;

#if IS_ENABLED(CONFIG_DAX)
struct dax_device *alloc_dax(void *private, const char *host,
		const struct dax_operations *ops, unsigned long flags);
void put_dax(struct dax_device *dax_dev);
void kill_dax(struct dax_device *dax_dev);
void dax_write_cache(struct dax_device *dax_dev, bool wc);
bool dax_write_cache_enabled(struct dax_device *dax_dev);
bool __dax_synchronous(struct dax_device *dax_dev);
static inline bool dax_synchronous(struct dax_device *dax_dev)
{
	return  __dax_synchronous(dax_dev);
}
void __set_dax_synchronous(struct dax_device *dax_dev);
static inline void set_dax_synchronous(struct dax_device *dax_dev)
{
	__set_dax_synchronous(dax_dev);
}
/*
 * Check if given mapping is supported by the file / underlying device.
 */
static inline bool daxdev_mapping_supported(struct vm_area_struct *vma,
					     struct dax_device *dax_dev)
{
	if (!(vma->vm_flags & VM_SYNC))
		return true;
	if (!IS_DAX(file_inode(vma->vm_file)))
		return false;
	return dax_synchronous(dax_dev);
}
#else
static inline struct dax_device *alloc_dax(void *private, const char *host,
		const struct dax_operations *ops, unsigned long flags)
{
	/*
	 * Callers should check IS_ENABLED(CONFIG_DAX) to know if this
	 * NULL is an error or expected.
	 */
	return NULL;
}
static inline void put_dax(struct dax_device *dax_dev)
{
}
static inline void kill_dax(struct dax_device *dax_dev)
{
}
static inline void dax_write_cache(struct dax_device *dax_dev, bool wc)
{
}
static inline bool dax_write_cache_enabled(struct dax_device *dax_dev)
{
	return false;
}
static inline bool dax_synchronous(struct dax_device *dax_dev)
{
	return true;
}
static inline void set_dax_synchronous(struct dax_device *dax_dev)
{
}
static inline bool daxdev_mapping_supported(struct vm_area_struct *vma,
				struct dax_device *dax_dev)
{
	return !(vma->vm_flags & VM_SYNC);
}
#endif

struct writeback_control;
int bdev_dax_pgoff(struct block_device *, sector_t, size_t, pgoff_t *pgoff);
#if IS_ENABLED(CONFIG_FS_DAX)
bool generic_fsdax_supported(struct dax_device *dax_dev,
		struct block_device *bdev, int blocksize, sector_t start,
		sector_t sectors);

bool dax_supported(struct dax_device *dax_dev, struct block_device *bdev,
		int blocksize, sector_t start, sector_t len);

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

struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev);
int dax_writeback_mapping_range(struct address_space *mapping,
		struct dax_device *dax_dev, struct writeback_control *wbc);

struct page *dax_layout_busy_page(struct address_space *mapping);
struct page *dax_layout_busy_page_range(struct address_space *mapping, loff_t start, loff_t end);
dax_entry_t dax_lock_page(struct page *page);
void dax_unlock_page(struct page *page, dax_entry_t cookie);
#else
#define generic_fsdax_supported		NULL

static inline bool dax_supported(struct dax_device *dax_dev,
		struct block_device *bdev, int blocksize, sector_t start,
		sector_t len)
{
	return false;
}

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

static inline struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev)
{
	return NULL;
}

static inline struct page *dax_layout_busy_page(struct address_space *mapping)
{
	return NULL;
}

static inline struct page *dax_layout_busy_page_range(struct address_space *mapping, pgoff_t start, pgoff_t nr_pages)
{
	return NULL;
}

static inline int dax_writeback_mapping_range(struct address_space *mapping,
		struct dax_device *dax_dev, struct writeback_control *wbc)
{
	return -EOPNOTSUPP;
}

static inline dax_entry_t dax_lock_page(struct page *page)
{
	if (IS_DAX(page->mapping->host))
		return ~0UL;
	return 0;
}

static inline void dax_unlock_page(struct page *page, dax_entry_t cookie)
{
}
#endif

#if IS_ENABLED(CONFIG_DAX)
int dax_read_lock(void);
void dax_read_unlock(int id);
#else
static inline int dax_read_lock(void)
{
	return 0;
}

static inline void dax_read_unlock(int id)
{
}
#endif /* CONFIG_DAX */
bool dax_alive(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);
size_t dax_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
		size_t bytes, struct iov_iter *i);
int dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff,
			size_t nr_pages);
void dax_flush(struct dax_device *dax_dev, void *addr, size_t size);

ssize_t dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter,
		const struct iomap_ops *ops);
vm_fault_t dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
		    pfn_t *pfnp, int *errp, const struct iomap_ops *ops);
vm_fault_t dax_finish_sync_fault(struct vm_fault *vmf,
		enum page_entry_size pe_size, pfn_t pfn);
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);
s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap);
static inline bool dax_mapping(struct address_space *mapping)
{
	return mapping->host && IS_DAX(mapping->host);
}

#ifdef CONFIG_DEV_DAX_HMEM_DEVICES
void hmem_register_device(int target_nid, struct resource *r);
#else
static inline void hmem_register_device(int target_nid, struct resource *r)
{
}
#endif

#endif
Commit	Line	Data
b2441318	1	/* SPDX-License-Identifier: GPL-2.0 */
c94c2acf MW	2	#ifndef _LINUX_DAX_H
	3	#define _LINUX_DAX_H
	4
	5	#include <linux/fs.h>
	6	#include <linux/mm.h>
4f622938	7	#include <linux/radix-tree.h>
c94c2acf	8
fefc1d97 PG	9	/* Flag for synchronous flush */
	10	#define DAXDEV_F_SYNC (1UL << 0)
	11
27359fd6 MW	12	typedef unsigned long dax_entry_t;
27359fd6 MW	13
a254e568	14	struct iomap_ops;
4f3b4f16	15	struct iomap;
6568b08b DW	16	struct dax_device;
	17	struct dax_operations {
	18	/*
	19	* direct_access: translate a device-relative
	20	* logical-page-offset into an absolute physical pfn. Return the
	21	* number of pages available for DAX at that pfn.
	22	*/
	23	long (direct_access)(struct dax_device , pgoff_t, long,
	24	void *, pfn_t );
7bf7eac8 DW	25	/*
	26	* Validate whether this device is usable as an fsdax backing
	27	* device.
	28	*/
	29	bool (dax_supported)(struct dax_device , struct block_device *, int,
	30	sector_t, sector_t);
5d61e43b	31	/* copy_from_iter: required operation for fs-dax direct-i/o */
0aed55af DW	32	size_t (copy_from_iter)(struct dax_device , pgoff_t, void *, size_t,
0aed55af DW	33	struct iov_iter *);
b3a9a0c3 DW	34	/* copy_to_iter: required operation for fs-dax direct-i/o */
	35	size_t (copy_to_iter)(struct dax_device , pgoff_t, void *, size_t,
	36	struct iov_iter *);
f605a263 VG	37	/* zero_page_range: required operation. Zero page range */
f605a263 VG	38	int (zero_page_range)(struct dax_device , pgoff_t, size_t);
6568b08b	39	};
a254e568	40
6e0c90d6 DW	41	extern struct attribute_group dax_attribute_group;
6e0c90d6 DW	42
f5705aa8	43	#if IS_ENABLED(CONFIG_DAX)
976431b0	44	struct dax_device alloc_dax(void private, const char *host,
fefc1d97	45	const struct dax_operations *ops, unsigned long flags);
f5705aa8	46	void put_dax(struct dax_device *dax_dev);
976431b0 DW	47	void kill_dax(struct dax_device *dax_dev);
	48	void dax_write_cache(struct dax_device *dax_dev, bool wc);
	49	bool dax_write_cache_enabled(struct dax_device *dax_dev);
fefc1d97 PG	50	bool __dax_synchronous(struct dax_device *dax_dev);
	51	static inline bool dax_synchronous(struct dax_device *dax_dev)
	52	{
	53	return __dax_synchronous(dax_dev);
	54	}
	55	void __set_dax_synchronous(struct dax_device *dax_dev);
	56	static inline void set_dax_synchronous(struct dax_device *dax_dev)
	57	{
	58	__set_dax_synchronous(dax_dev);
	59	}
32de1484 PG	60	/*
	61	* Check if given mapping is supported by the file / underlying device.
	62	*/
	63	static inline bool daxdev_mapping_supported(struct vm_area_struct *vma,
	64	struct dax_device *dax_dev)
	65	{
	66	if (!(vma->vm_flags & VM_SYNC))
	67	return true;
	68	if (!IS_DAX(file_inode(vma->vm_file)))
	69	return false;
	70	return dax_synchronous(dax_dev);
	71	}
f5705aa8	72	#else
976431b0	73	static inline struct dax_device alloc_dax(void private, const char *host,
fefc1d97	74	const struct dax_operations *ops, unsigned long flags)
976431b0 DW	75	{
	76	/*
	77	* Callers should check IS_ENABLED(CONFIG_DAX) to know if this
	78	* NULL is an error or expected.
	79	*/
	80	return NULL;
	81	}
f5705aa8 DW	82	static inline void put_dax(struct dax_device *dax_dev)
	83	{
	84	}
976431b0 DW	85	static inline void kill_dax(struct dax_device *dax_dev)
	86	{
	87	}
	88	static inline void dax_write_cache(struct dax_device *dax_dev, bool wc)
	89	{
	90	}
	91	static inline bool dax_write_cache_enabled(struct dax_device *dax_dev)
	92	{
	93	return false;
	94	}
fefc1d97 PG	95	static inline bool dax_synchronous(struct dax_device *dax_dev)
	96	{
	97	return true;
	98	}
	99	static inline void set_dax_synchronous(struct dax_device *dax_dev)
	100	{
	101	}
32de1484 PG	102	static inline bool daxdev_mapping_supported(struct vm_area_struct *vma,
	103	struct dax_device *dax_dev)
	104	{
	105	return !(vma->vm_flags & VM_SYNC);
	106	}
f5705aa8 DW	107	#endif
f5705aa8 DW	108
f44c7763	109	struct writeback_control;
ef510424 DW	110	int bdev_dax_pgoff(struct block_device , sector_t, size_t, pgoff_t pgoff);
ef510424 DW	111	#if IS_ENABLED(CONFIG_FS_DAX)
cd93a2a4	112	bool generic_fsdax_supported(struct dax_device *dax_dev,
7bf7eac8 DW	113	struct block_device *bdev, int blocksize, sector_t start,
7bf7eac8 DW	114	sector_t sectors);
7bf7eac8	115
60b8340f CH	116	bool dax_supported(struct dax_device dax_dev, struct block_device bdev,
	117	int blocksize, sector_t start, sector_t len);
	118
f5705aa8 DW	119	static inline void fs_put_dax(struct dax_device *dax_dev)
	120	{
	121	put_dax(dax_dev);
	122	}
	123
78f35473	124	struct dax_device fs_dax_get_by_bdev(struct block_device bdev);
f44c7763	125	int dax_writeback_mapping_range(struct address_space *mapping,
3f666c56	126	struct dax_device dax_dev, struct writeback_control wbc);
5fac7408 DW	127
5fac7408 DW	128	struct page dax_layout_busy_page(struct address_space mapping);
6bbdd563	129	struct page dax_layout_busy_page_range(struct address_space mapping, loff_t start, loff_t end);
27359fd6 MW	130	dax_entry_t dax_lock_page(struct page *page);
27359fd6 MW	131	void dax_unlock_page(struct page *page, dax_entry_t cookie);
ef510424	132	#else
cd93a2a4	133	#define generic_fsdax_supported NULL
7bf7eac8	134
60b8340f CH	135	static inline bool dax_supported(struct dax_device *dax_dev,
	136	struct block_device *bdev, int blocksize, sector_t start,
	137	sector_t len)
	138	{
	139	return false;
	140	}
	141
f5705aa8	142	static inline void fs_put_dax(struct dax_device *dax_dev)
ef510424 DW	143	{
ef510424 DW	144	}
78f35473 DW	145
	146	static inline struct dax_device fs_dax_get_by_bdev(struct block_device bdev)
	147	{
	148	return NULL;
	149	}
f44c7763	150
5fac7408 DW	151	static inline struct page dax_layout_busy_page(struct address_space mapping)
	152	{
	153	return NULL;
	154	}
	155
6bbdd563 VG	156	static inline struct page dax_layout_busy_page_range(struct address_space mapping, pgoff_t start, pgoff_t nr_pages)
	157	{
	158	return NULL;
	159	}
	160
f44c7763	161	static inline int dax_writeback_mapping_range(struct address_space *mapping,
3f666c56	162	struct dax_device dax_dev, struct writeback_control wbc)
f44c7763 DW	163	{
	164	return -EOPNOTSUPP;
	165	}
c2a7d2a1	166
27359fd6	167	static inline dax_entry_t dax_lock_page(struct page *page)
c2a7d2a1 DW	168	{
c2a7d2a1 DW	169	if (IS_DAX(page->mapping->host))
27359fd6 MW	170	return ~0UL;
27359fd6 MW	171	return 0;
c2a7d2a1 DW	172	}
c2a7d2a1 DW	173
27359fd6	174	static inline void dax_unlock_page(struct page *page, dax_entry_t cookie)
c2a7d2a1 DW	175	{
c2a7d2a1 DW	176	}
ef510424 DW	177	#endif
ef510424 DW	178
e2ec5128	179	#if IS_ENABLED(CONFIG_DAX)
7b6be844 DW	180	int dax_read_lock(void);
7b6be844 DW	181	void dax_read_unlock(int id);
e2ec5128 JK	182	#else
	183	static inline int dax_read_lock(void)
	184	{
	185	return 0;
	186	}
	187
	188	static inline void dax_read_unlock(int id)
	189	{
	190	}
	191	#endif /* CONFIG_DAX */
c1d6e828	192	bool dax_alive(struct dax_device *dax_dev);
c1d6e828	193	void dax_get_private(struct dax_device dax_dev);
b0686260 DW	194	long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages,
b0686260 DW	195	void *kaddr, pfn_t pfn);
7e026c8c DW	196	size_t dax_copy_from_iter(struct dax_device dax_dev, pgoff_t pgoff, void addr,
7e026c8c DW	197	size_t bytes, struct iov_iter *i);
b3a9a0c3 DW	198	size_t dax_copy_to_iter(struct dax_device dax_dev, pgoff_t pgoff, void addr,
b3a9a0c3 DW	199	size_t bytes, struct iov_iter *i);
f605a263 VG	200	int dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff,
f605a263 VG	201	size_t nr_pages);
c3ca015f	202	void dax_flush(struct dax_device dax_dev, void addr, size_t size);
7b6be844	203
11c59c92	204	ssize_t dax_iomap_rw(struct kiocb iocb, struct iov_iter iter,
8ff6daa1	205	const struct iomap_ops *ops);
f77bc3a8	206	vm_fault_t dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
c0b24625	207	pfn_t pfnp, int errp, const struct iomap_ops *ops);
ab77dab4 SJ	208	vm_fault_t dax_finish_sync_fault(struct vm_fault *vmf,
ab77dab4 SJ	209	enum page_entry_size pe_size, pfn_t pfn);
ac401cc7	210	int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index);
c6dcf52c JK	211	int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
c6dcf52c JK	212	pgoff_t index);
81ee8e52	213	s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap);
f9fe48be RZ	214	static inline bool dax_mapping(struct address_space *mapping)
	215	{
	216	return mapping->host && IS_DAX(mapping->host);
	217	}
7f6d5b52	218
c01044cc DW	219	#ifdef CONFIG_DEV_DAX_HMEM_DEVICES
	220	void hmem_register_device(int target_nid, struct resource *r);
	221	#else
	222	static inline void hmem_register_device(int target_nid, struct resource *r)
	223	{
	224	}
	225	#endif
	226
c94c2acf	227	#endif