[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);
	/* 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

void set_dax_nocache(struct dax_device *dax_dev);
void set_dax_nomc(struct dax_device *dax_dev);

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);
f605a263 VG	31	/* zero_page_range: required operation. Zero page range */
f605a263 VG	32	int (zero_page_range)(struct dax_device , pgoff_t, size_t);
6568b08b	33	};
a254e568	34
f5705aa8	35	#if IS_ENABLED(CONFIG_DAX)
30c6828a	36	struct dax_device alloc_dax(void private, const struct dax_operations *ops);
f5705aa8	37	void put_dax(struct dax_device *dax_dev);
976431b0 DW	38	void kill_dax(struct dax_device *dax_dev);
	39	void dax_write_cache(struct dax_device *dax_dev, bool wc);
	40	bool dax_write_cache_enabled(struct dax_device *dax_dev);
fd1d00ec CH	41	bool dax_synchronous(struct dax_device *dax_dev);
fd1d00ec CH	42	void set_dax_synchronous(struct dax_device *dax_dev);
32de1484 PG	43	/*
	44	* Check if given mapping is supported by the file / underlying device.
	45	*/
	46	static inline bool daxdev_mapping_supported(struct vm_area_struct *vma,
	47	struct dax_device *dax_dev)
	48	{
	49	if (!(vma->vm_flags & VM_SYNC))
	50	return true;
	51	if (!IS_DAX(file_inode(vma->vm_file)))
	52	return false;
	53	return dax_synchronous(dax_dev);
	54	}
f5705aa8	55	#else
fb08a190	56	static inline struct dax_device alloc_dax(void private,
30c6828a	57	const struct dax_operations *ops)
976431b0 DW	58	{
	59	/*
	60	* Callers should check IS_ENABLED(CONFIG_DAX) to know if this
	61	* NULL is an error or expected.
	62	*/
	63	return NULL;
	64	}
f5705aa8 DW	65	static inline void put_dax(struct dax_device *dax_dev)
	66	{
	67	}
976431b0 DW	68	static inline void kill_dax(struct dax_device *dax_dev)
	69	{
	70	}
	71	static inline void dax_write_cache(struct dax_device *dax_dev, bool wc)
	72	{
	73	}
	74	static inline bool dax_write_cache_enabled(struct dax_device *dax_dev)
	75	{
	76	return false;
	77	}
fefc1d97 PG	78	static inline bool dax_synchronous(struct dax_device *dax_dev)
	79	{
	80	return true;
	81	}
	82	static inline void set_dax_synchronous(struct dax_device *dax_dev)
	83	{
	84	}
32de1484 PG	85	static inline bool daxdev_mapping_supported(struct vm_area_struct *vma,
	86	struct dax_device *dax_dev)
	87	{
	88	return !(vma->vm_flags & VM_SYNC);
	89	}
f5705aa8 DW	90	#endif
f5705aa8 DW	91
7ac5360c CH	92	void set_dax_nocache(struct dax_device *dax_dev);
	93	void set_dax_nomc(struct dax_device *dax_dev);
	94
f44c7763	95	struct writeback_control;
2ede8923	96	#if defined(CONFIG_BLOCK) && defined(CONFIG_FS_DAX)
fb08a190 CH	97	int dax_add_host(struct dax_device dax_dev, struct gendisk disk);
fb08a190 CH	98	void dax_remove_host(struct gendisk *disk);
2ede8923 CH	99	struct dax_device fs_dax_get_by_bdev(struct block_device bdev,
2ede8923 CH	100	u64 *start_off);
f5705aa8 DW	101	static inline void fs_put_dax(struct dax_device *dax_dev)
	102	{
	103	put_dax(dax_dev);
	104	}
ef510424	105	#else
fb08a190 CH	106	static inline int dax_add_host(struct dax_device dax_dev, struct gendisk disk)
	107	{
	108	return 0;
	109	}
	110	static inline void dax_remove_host(struct gendisk *disk)
	111	{
	112	}
cd913c76 CH	113	static inline struct dax_device fs_dax_get_by_bdev(struct block_device bdev,
cd913c76 CH	114	u64 *start_off)
78f35473 DW	115	{
	116	return NULL;
	117	}
2ede8923 CH	118	static inline void fs_put_dax(struct dax_device *dax_dev)
	119	{
	120	}
	121	#endif /* CONFIG_BLOCK && CONFIG_FS_DAX */
f44c7763	122
2ede8923 CH	123	#if IS_ENABLED(CONFIG_FS_DAX)
	124	int dax_writeback_mapping_range(struct address_space *mapping,
	125	struct dax_device dax_dev, struct writeback_control wbc);
	126
	127	struct page dax_layout_busy_page(struct address_space mapping);
	128	struct page dax_layout_busy_page_range(struct address_space mapping, loff_t start, loff_t end);
	129	dax_entry_t dax_lock_page(struct page *page);
	130	void dax_unlock_page(struct page *page, dax_entry_t cookie);
	131	#else
5fac7408 DW	132	static inline struct page dax_layout_busy_page(struct address_space mapping)
	133	{
	134	return NULL;
	135	}
	136
6bbdd563 VG	137	static inline struct page dax_layout_busy_page_range(struct address_space mapping, pgoff_t start, pgoff_t nr_pages)
	138	{
	139	return NULL;
	140	}
	141
f44c7763	142	static inline int dax_writeback_mapping_range(struct address_space *mapping,
3f666c56	143	struct dax_device dax_dev, struct writeback_control wbc)
f44c7763 DW	144	{
	145	return -EOPNOTSUPP;
	146	}
c2a7d2a1	147
27359fd6	148	static inline dax_entry_t dax_lock_page(struct page *page)
c2a7d2a1 DW	149	{
c2a7d2a1 DW	150	if (IS_DAX(page->mapping->host))
27359fd6 MW	151	return ~0UL;
27359fd6 MW	152	return 0;
c2a7d2a1 DW	153	}
c2a7d2a1 DW	154
27359fd6	155	static inline void dax_unlock_page(struct page *page, dax_entry_t cookie)
c2a7d2a1 DW	156	{
c2a7d2a1 DW	157	}
ef510424 DW	158	#endif
ef510424 DW	159
c6f40468 CH	160	int dax_zero_range(struct inode inode, loff_t pos, loff_t len, bool did_zero,
	161	const struct iomap_ops *ops);
	162	int dax_truncate_page(struct inode inode, loff_t pos, bool did_zero,
	163	const struct iomap_ops *ops);
	164
e2ec5128	165	#if IS_ENABLED(CONFIG_DAX)
7b6be844 DW	166	int dax_read_lock(void);
7b6be844 DW	167	void dax_read_unlock(int id);
e2ec5128 JK	168	#else
	169	static inline int dax_read_lock(void)
	170	{
	171	return 0;
	172	}
	173
	174	static inline void dax_read_unlock(int id)
	175	{
	176	}
	177	#endif /* CONFIG_DAX */
c1d6e828	178	bool dax_alive(struct dax_device *dax_dev);
c1d6e828	179	void dax_get_private(struct dax_device dax_dev);
b0686260 DW	180	long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages,
b0686260 DW	181	void *kaddr, pfn_t pfn);
7e026c8c DW	182	size_t dax_copy_from_iter(struct dax_device dax_dev, pgoff_t pgoff, void addr,
7e026c8c DW	183	size_t bytes, struct iov_iter *i);
b3a9a0c3 DW	184	size_t dax_copy_to_iter(struct dax_device dax_dev, pgoff_t pgoff, void addr,
b3a9a0c3 DW	185	size_t bytes, struct iov_iter *i);
f605a263 VG	186	int dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff,
f605a263 VG	187	size_t nr_pages);
c3ca015f	188	void dax_flush(struct dax_device dax_dev, void addr, size_t size);
7b6be844	189
11c59c92	190	ssize_t dax_iomap_rw(struct kiocb iocb, struct iov_iter iter,
8ff6daa1	191	const struct iomap_ops *ops);
f77bc3a8	192	vm_fault_t dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
c0b24625	193	pfn_t pfnp, int errp, const struct iomap_ops *ops);
ab77dab4 SJ	194	vm_fault_t dax_finish_sync_fault(struct vm_fault *vmf,
ab77dab4 SJ	195	enum page_entry_size pe_size, pfn_t pfn);
ac401cc7	196	int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index);
c6dcf52c JK	197	int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
c6dcf52c JK	198	pgoff_t index);
f9fe48be RZ	199	static inline bool dax_mapping(struct address_space *mapping)
	200	{
	201	return mapping->host && IS_DAX(mapping->host);
	202	}
7f6d5b52	203
c01044cc DW	204	#ifdef CONFIG_DEV_DAX_HMEM_DEVICES
	205	void hmem_register_device(int target_nid, struct resource *r);
	206	#else
	207	static inline void hmem_register_device(int target_nid, struct resource *r)
	208	{
	209	}
	210	#endif
	211
c94c2acf	212	#endif