[mirror_ubuntu-kernels.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 *dax_get_by_host(const char *host);
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);
}
bool dax_supported(struct dax_device *dax_dev, struct block_device *bdev,
		int blocksize, sector_t start, sector_t len);
/*
 * 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 *dax_get_by_host(const char *host)
{
	return NULL;
}
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 dax_supported(struct dax_device *dax_dev,
		struct block_device *bdev, int blocksize, sector_t start,
		sector_t len)
{
	return false;
}
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 __bdev_dax_supported(struct block_device *bdev, int blocksize);
static inline bool bdev_dax_supported(struct block_device *bdev, int blocksize)
{
	return __bdev_dax_supported(bdev, blocksize);
}

bool __generic_fsdax_supported(struct dax_device *dax_dev,
		struct block_device *bdev, int blocksize, sector_t start,
		sector_t sectors);
static inline bool generic_fsdax_supported(struct dax_device *dax_dev,
		struct block_device *bdev, int blocksize, sector_t start,
		sector_t sectors)
{
	return __generic_fsdax_supported(dax_dev, bdev, blocksize, start,
			sectors);
}

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
static inline bool bdev_dax_supported(struct block_device *bdev,
		int blocksize)
{
	return false;
}

static inline bool generic_fsdax_supported(struct dax_device *dax_dev,
		struct block_device *bdev, int blocksize, sector_t start,
		sector_t sectors)
{
	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 DW	43	#if IS_ENABLED(CONFIG_DAX)
f5705aa8 DW	44	struct dax_device dax_get_by_host(const char host);
976431b0	45	struct dax_device alloc_dax(void private, const char *host,
fefc1d97	46	const struct dax_operations *ops, unsigned long flags);
f5705aa8	47	void put_dax(struct dax_device *dax_dev);
976431b0 DW	48	void kill_dax(struct dax_device *dax_dev);
	49	void dax_write_cache(struct dax_device *dax_dev, bool wc);
	50	bool dax_write_cache_enabled(struct dax_device *dax_dev);
fefc1d97 PG	51	bool __dax_synchronous(struct dax_device *dax_dev);
	52	static inline bool dax_synchronous(struct dax_device *dax_dev)
	53	{
	54	return __dax_synchronous(dax_dev);
	55	}
	56	void __set_dax_synchronous(struct dax_device *dax_dev);
	57	static inline void set_dax_synchronous(struct dax_device *dax_dev)
	58	{
	59	__set_dax_synchronous(dax_dev);
	60	}
88b67edd JK	61	bool dax_supported(struct dax_device dax_dev, struct block_device bdev,
88b67edd JK	62	int blocksize, sector_t start, sector_t len);
32de1484 PG	63	/*
	64	* Check if given mapping is supported by the file / underlying device.
	65	*/
	66	static inline bool daxdev_mapping_supported(struct vm_area_struct *vma,
	67	struct dax_device *dax_dev)
	68	{
	69	if (!(vma->vm_flags & VM_SYNC))
	70	return true;
	71	if (!IS_DAX(file_inode(vma->vm_file)))
	72	return false;
	73	return dax_synchronous(dax_dev);
	74	}
f5705aa8 DW	75	#else
	76	static inline struct dax_device dax_get_by_host(const char host)
	77	{
	78	return NULL;
	79	}
976431b0	80	static inline struct dax_device alloc_dax(void private, const char *host,
fefc1d97	81	const struct dax_operations *ops, unsigned long flags)
976431b0 DW	82	{
	83	/*
	84	* Callers should check IS_ENABLED(CONFIG_DAX) to know if this
	85	* NULL is an error or expected.
	86	*/
	87	return NULL;
	88	}
f5705aa8 DW	89	static inline void put_dax(struct dax_device *dax_dev)
	90	{
	91	}
976431b0 DW	92	static inline void kill_dax(struct dax_device *dax_dev)
	93	{
	94	}
	95	static inline void dax_write_cache(struct dax_device *dax_dev, bool wc)
	96	{
	97	}
	98	static inline bool dax_write_cache_enabled(struct dax_device *dax_dev)
	99	{
	100	return false;
	101	}
fefc1d97 PG	102	static inline bool dax_synchronous(struct dax_device *dax_dev)
	103	{
	104	return true;
	105	}
	106	static inline void set_dax_synchronous(struct dax_device *dax_dev)
	107	{
	108	}
88b67edd JK	109	static inline bool dax_supported(struct dax_device *dax_dev,
	110	struct block_device *bdev, int blocksize, sector_t start,
	111	sector_t len)
	112	{
	113	return false;
	114	}
32de1484 PG	115	static inline bool daxdev_mapping_supported(struct vm_area_struct *vma,
	116	struct dax_device *dax_dev)
	117	{
	118	return !(vma->vm_flags & VM_SYNC);
	119	}
f5705aa8 DW	120	#endif
f5705aa8 DW	121
f44c7763	122	struct writeback_control;
ef510424 DW	123	int bdev_dax_pgoff(struct block_device , sector_t, size_t, pgoff_t pgoff);
ef510424 DW	124	#if IS_ENABLED(CONFIG_FS_DAX)
80660f20 DJ	125	bool __bdev_dax_supported(struct block_device *bdev, int blocksize);
80660f20 DJ	126	static inline bool bdev_dax_supported(struct block_device *bdev, int blocksize)
ef510424	127	{
ba23cba9	128	return __bdev_dax_supported(bdev, blocksize);
ef510424	129	}
f5705aa8	130
7bf7eac8 DW	131	bool __generic_fsdax_supported(struct dax_device *dax_dev,
	132	struct block_device *bdev, int blocksize, sector_t start,
	133	sector_t sectors);
	134	static inline bool generic_fsdax_supported(struct dax_device *dax_dev,
	135	struct block_device *bdev, int blocksize, sector_t start,
	136	sector_t sectors)
	137	{
	138	return __generic_fsdax_supported(dax_dev, bdev, blocksize, start,
	139	sectors);
	140	}
	141
f5705aa8 DW	142	static inline void fs_put_dax(struct dax_device *dax_dev)
	143	{
	144	put_dax(dax_dev);
	145	}
	146
78f35473	147	struct dax_device fs_dax_get_by_bdev(struct block_device bdev);
f44c7763	148	int dax_writeback_mapping_range(struct address_space *mapping,
3f666c56	149	struct dax_device dax_dev, struct writeback_control wbc);
5fac7408 DW	150
5fac7408 DW	151	struct page dax_layout_busy_page(struct address_space mapping);
6bbdd563	152	struct page dax_layout_busy_page_range(struct address_space mapping, loff_t start, loff_t end);
27359fd6 MW	153	dax_entry_t dax_lock_page(struct page *page);
27359fd6 MW	154	void dax_unlock_page(struct page *page, dax_entry_t cookie);
ef510424	155	#else
80660f20	156	static inline bool bdev_dax_supported(struct block_device *bdev,
ba23cba9	157	int blocksize)
ef510424	158	{
80660f20	159	return false;
ef510424	160	}
ef510424	161
7bf7eac8 DW	162	static inline bool generic_fsdax_supported(struct dax_device *dax_dev,
	163	struct block_device *bdev, int blocksize, sector_t start,
	164	sector_t sectors)
	165	{
	166	return false;
	167	}
	168
f5705aa8	169	static inline void fs_put_dax(struct dax_device *dax_dev)
ef510424 DW	170	{
ef510424 DW	171	}
78f35473 DW	172
	173	static inline struct dax_device fs_dax_get_by_bdev(struct block_device bdev)
	174	{
	175	return NULL;
	176	}
f44c7763	177
5fac7408 DW	178	static inline struct page dax_layout_busy_page(struct address_space mapping)
	179	{
	180	return NULL;
	181	}
	182
6bbdd563 VG	183	static inline struct page dax_layout_busy_page_range(struct address_space mapping, pgoff_t start, pgoff_t nr_pages)
	184	{
	185	return NULL;
	186	}
	187
f44c7763	188	static inline int dax_writeback_mapping_range(struct address_space *mapping,
3f666c56	189	struct dax_device dax_dev, struct writeback_control wbc)
f44c7763 DW	190	{
	191	return -EOPNOTSUPP;
	192	}
c2a7d2a1	193
27359fd6	194	static inline dax_entry_t dax_lock_page(struct page *page)
c2a7d2a1 DW	195	{
c2a7d2a1 DW	196	if (IS_DAX(page->mapping->host))
27359fd6 MW	197	return ~0UL;
27359fd6 MW	198	return 0;
c2a7d2a1 DW	199	}
c2a7d2a1 DW	200
27359fd6	201	static inline void dax_unlock_page(struct page *page, dax_entry_t cookie)
c2a7d2a1 DW	202	{
c2a7d2a1 DW	203	}
ef510424 DW	204	#endif
ef510424 DW	205
e2ec5128	206	#if IS_ENABLED(CONFIG_DAX)
7b6be844 DW	207	int dax_read_lock(void);
7b6be844 DW	208	void dax_read_unlock(int id);
e2ec5128 JK	209	#else
	210	static inline int dax_read_lock(void)
	211	{
	212	return 0;
	213	}
	214
	215	static inline void dax_read_unlock(int id)
	216	{
	217	}
	218	#endif /* CONFIG_DAX */
c1d6e828	219	bool dax_alive(struct dax_device *dax_dev);
c1d6e828	220	void dax_get_private(struct dax_device dax_dev);
b0686260 DW	221	long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages,
b0686260 DW	222	void *kaddr, pfn_t pfn);
7e026c8c DW	223	size_t dax_copy_from_iter(struct dax_device dax_dev, pgoff_t pgoff, void addr,
7e026c8c DW	224	size_t bytes, struct iov_iter *i);
b3a9a0c3 DW	225	size_t dax_copy_to_iter(struct dax_device dax_dev, pgoff_t pgoff, void addr,
b3a9a0c3 DW	226	size_t bytes, struct iov_iter *i);
f605a263 VG	227	int dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff,
f605a263 VG	228	size_t nr_pages);
c3ca015f	229	void dax_flush(struct dax_device dax_dev, void addr, size_t size);
7b6be844	230
11c59c92	231	ssize_t dax_iomap_rw(struct kiocb iocb, struct iov_iter iter,
8ff6daa1	232	const struct iomap_ops *ops);
f77bc3a8	233	vm_fault_t dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
c0b24625	234	pfn_t pfnp, int errp, const struct iomap_ops *ops);
ab77dab4 SJ	235	vm_fault_t dax_finish_sync_fault(struct vm_fault *vmf,
ab77dab4 SJ	236	enum page_entry_size pe_size, pfn_t pfn);
ac401cc7	237	int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index);
c6dcf52c JK	238	int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
c6dcf52c JK	239	pgoff_t index);
81ee8e52	240	s64 dax_iomap_zero(loff_t pos, u64 length, struct iomap *iomap);
f9fe48be RZ	241	static inline bool dax_mapping(struct address_space *mapping)
	242	{
	243	return mapping->host && IS_DAX(mapping->host);
	244	}
7f6d5b52	245
c01044cc DW	246	#ifdef CONFIG_DEV_DAX_HMEM_DEVICES
	247	void hmem_register_device(int target_nid, struct resource *r);
	248	#else
	249	static inline void hmem_register_device(int target_nid, struct resource *r)
	250	{
	251	}
	252	#endif
	253
c94c2acf	254	#endif