[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>

typedef unsigned long dax_entry_t;

struct dax_device;
struct gendisk;
struct iomap_ops;
struct iomap_iter;
struct iomap;

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);
};

#if IS_ENABLED(CONFIG_DAX)
struct dax_device *alloc_dax(void *private, const struct dax_operations *ops);
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);
void set_dax_synchronous(struct dax_device *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 struct dax_operations *ops)
{
	/*
	 * 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;
#if defined(CONFIG_BLOCK) && defined(CONFIG_FS_DAX)
int dax_add_host(struct dax_device *dax_dev, struct gendisk *disk);
void dax_remove_host(struct gendisk *disk);
struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev,
		u64 *start_off);
static inline void fs_put_dax(struct dax_device *dax_dev)
{
	put_dax(dax_dev);
}
#else
static inline int dax_add_host(struct dax_device *dax_dev, struct gendisk *disk)
{
	return 0;
}
static inline void dax_remove_host(struct gendisk *disk)
{
}
static inline struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev,
		u64 *start_off)
{
	return NULL;
}
static inline void fs_put_dax(struct dax_device *dax_dev)
{
}
#endif /* CONFIG_BLOCK && CONFIG_FS_DAX */

#if IS_ENABLED(CONFIG_FS_DAX)
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
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

int dax_zero_range(struct inode *inode, loff_t pos, loff_t len, bool *did_zero,
		const struct iomap_ops *ops);
int dax_truncate_page(struct inode *inode, loff_t pos, bool *did_zero,
		const struct iomap_ops *ops);

#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);
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
27359fd6 MW	9	typedef unsigned long dax_entry_t;
27359fd6 MW	10
fb08a190 CH	11	struct dax_device;
fb08a190 CH	12	struct gendisk;
a254e568	13	struct iomap_ops;
c6f40468	14	struct iomap_iter;
4f3b4f16	15	struct iomap;
fb08a190	16
6568b08b DW	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
f5705aa8	41	#if IS_ENABLED(CONFIG_DAX)
30c6828a	42	struct dax_device alloc_dax(void private, const struct dax_operations *ops);
f5705aa8	43	void put_dax(struct dax_device *dax_dev);
976431b0 DW	44	void kill_dax(struct dax_device *dax_dev);
	45	void dax_write_cache(struct dax_device *dax_dev, bool wc);
	46	bool dax_write_cache_enabled(struct dax_device *dax_dev);
fd1d00ec CH	47	bool dax_synchronous(struct dax_device *dax_dev);
fd1d00ec CH	48	void set_dax_synchronous(struct dax_device *dax_dev);
32de1484 PG	49	/*
	50	* Check if given mapping is supported by the file / underlying device.
	51	*/
	52	static inline bool daxdev_mapping_supported(struct vm_area_struct *vma,
	53	struct dax_device *dax_dev)
	54	{
	55	if (!(vma->vm_flags & VM_SYNC))
	56	return true;
	57	if (!IS_DAX(file_inode(vma->vm_file)))
	58	return false;
	59	return dax_synchronous(dax_dev);
	60	}
f5705aa8	61	#else
fb08a190	62	static inline struct dax_device alloc_dax(void private,
30c6828a	63	const struct dax_operations *ops)
976431b0 DW	64	{
	65	/*
	66	* Callers should check IS_ENABLED(CONFIG_DAX) to know if this
	67	* NULL is an error or expected.
	68	*/
	69	return NULL;
	70	}
f5705aa8 DW	71	static inline void put_dax(struct dax_device *dax_dev)
	72	{
	73	}
976431b0 DW	74	static inline void kill_dax(struct dax_device *dax_dev)
	75	{
	76	}
	77	static inline void dax_write_cache(struct dax_device *dax_dev, bool wc)
	78	{
	79	}
	80	static inline bool dax_write_cache_enabled(struct dax_device *dax_dev)
	81	{
	82	return false;
	83	}
fefc1d97 PG	84	static inline bool dax_synchronous(struct dax_device *dax_dev)
	85	{
	86	return true;
	87	}
	88	static inline void set_dax_synchronous(struct dax_device *dax_dev)
	89	{
	90	}
32de1484 PG	91	static inline bool daxdev_mapping_supported(struct vm_area_struct *vma,
	92	struct dax_device *dax_dev)
	93	{
	94	return !(vma->vm_flags & VM_SYNC);
	95	}
f5705aa8 DW	96	#endif
f5705aa8 DW	97
f44c7763	98	struct writeback_control;
2ede8923	99	#if defined(CONFIG_BLOCK) && defined(CONFIG_FS_DAX)
fb08a190 CH	100	int dax_add_host(struct dax_device dax_dev, struct gendisk disk);
fb08a190 CH	101	void dax_remove_host(struct gendisk *disk);
2ede8923 CH	102	struct dax_device fs_dax_get_by_bdev(struct block_device bdev,
2ede8923 CH	103	u64 *start_off);
f5705aa8 DW	104	static inline void fs_put_dax(struct dax_device *dax_dev)
	105	{
	106	put_dax(dax_dev);
	107	}
ef510424	108	#else
fb08a190 CH	109	static inline int dax_add_host(struct dax_device dax_dev, struct gendisk disk)
	110	{
	111	return 0;
	112	}
	113	static inline void dax_remove_host(struct gendisk *disk)
	114	{
	115	}
cd913c76 CH	116	static inline struct dax_device fs_dax_get_by_bdev(struct block_device bdev,
cd913c76 CH	117	u64 *start_off)
78f35473 DW	118	{
	119	return NULL;
	120	}
2ede8923 CH	121	static inline void fs_put_dax(struct dax_device *dax_dev)
	122	{
	123	}
	124	#endif /* CONFIG_BLOCK && CONFIG_FS_DAX */
f44c7763	125
2ede8923 CH	126	#if IS_ENABLED(CONFIG_FS_DAX)
	127	int dax_writeback_mapping_range(struct address_space *mapping,
	128	struct dax_device dax_dev, struct writeback_control wbc);
	129
	130	struct page dax_layout_busy_page(struct address_space mapping);
	131	struct page dax_layout_busy_page_range(struct address_space mapping, loff_t start, loff_t end);
	132	dax_entry_t dax_lock_page(struct page *page);
	133	void dax_unlock_page(struct page *page, dax_entry_t cookie);
	134	#else
5fac7408 DW	135	static inline struct page dax_layout_busy_page(struct address_space mapping)
	136	{
	137	return NULL;
	138	}
	139
6bbdd563 VG	140	static inline struct page dax_layout_busy_page_range(struct address_space mapping, pgoff_t start, pgoff_t nr_pages)
	141	{
	142	return NULL;
	143	}
	144
f44c7763	145	static inline int dax_writeback_mapping_range(struct address_space *mapping,
3f666c56	146	struct dax_device dax_dev, struct writeback_control wbc)
f44c7763 DW	147	{
	148	return -EOPNOTSUPP;
	149	}
c2a7d2a1	150
27359fd6	151	static inline dax_entry_t dax_lock_page(struct page *page)
c2a7d2a1 DW	152	{
c2a7d2a1 DW	153	if (IS_DAX(page->mapping->host))
27359fd6 MW	154	return ~0UL;
27359fd6 MW	155	return 0;
c2a7d2a1 DW	156	}
c2a7d2a1 DW	157
27359fd6	158	static inline void dax_unlock_page(struct page *page, dax_entry_t cookie)
c2a7d2a1 DW	159	{
c2a7d2a1 DW	160	}
ef510424 DW	161	#endif
ef510424 DW	162
c6f40468 CH	163	int dax_zero_range(struct inode inode, loff_t pos, loff_t len, bool did_zero,
	164	const struct iomap_ops *ops);
	165	int dax_truncate_page(struct inode inode, loff_t pos, bool did_zero,
	166	const struct iomap_ops *ops);
	167
e2ec5128	168	#if IS_ENABLED(CONFIG_DAX)
7b6be844 DW	169	int dax_read_lock(void);
7b6be844 DW	170	void dax_read_unlock(int id);
e2ec5128 JK	171	#else
	172	static inline int dax_read_lock(void)
	173	{
	174	return 0;
	175	}
	176
	177	static inline void dax_read_unlock(int id)
	178	{
	179	}
	180	#endif /* CONFIG_DAX */
c1d6e828	181	bool dax_alive(struct dax_device *dax_dev);
c1d6e828	182	void dax_get_private(struct dax_device dax_dev);
b0686260 DW	183	long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages,
b0686260 DW	184	void *kaddr, pfn_t pfn);
7e026c8c DW	185	size_t dax_copy_from_iter(struct dax_device dax_dev, pgoff_t pgoff, void addr,
7e026c8c DW	186	size_t bytes, struct iov_iter *i);
b3a9a0c3 DW	187	size_t dax_copy_to_iter(struct dax_device dax_dev, pgoff_t pgoff, void addr,
b3a9a0c3 DW	188	size_t bytes, struct iov_iter *i);
f605a263 VG	189	int dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff,
f605a263 VG	190	size_t nr_pages);
c3ca015f	191	void dax_flush(struct dax_device dax_dev, void addr, size_t size);
7b6be844	192
11c59c92	193	ssize_t dax_iomap_rw(struct kiocb iocb, struct iov_iter iter,
8ff6daa1	194	const struct iomap_ops *ops);
f77bc3a8	195	vm_fault_t dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
c0b24625	196	pfn_t pfnp, int errp, const struct iomap_ops *ops);
ab77dab4 SJ	197	vm_fault_t dax_finish_sync_fault(struct vm_fault *vmf,
ab77dab4 SJ	198	enum page_entry_size pe_size, pfn_t pfn);
ac401cc7	199	int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index);
c6dcf52c JK	200	int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
c6dcf52c JK	201	pgoff_t index);
f9fe48be RZ	202	static inline bool dax_mapping(struct address_space *mapping)
	203	{
	204	return mapping->host && IS_DAX(mapping->host);
	205	}
7f6d5b52	206
c01044cc DW	207	#ifdef CONFIG_DEV_DAX_HMEM_DEVICES
	208	void hmem_register_device(int target_nid, struct resource *r);
	209	#else
	210	static inline void hmem_register_device(int target_nid, struct resource *r)
	211	{
	212	}
	213	#endif
	214
c94c2acf	215	#endif