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

#include <linux/bio.h>
#include <linux/blkdev.h>
#include <linux/errno.h>
#include <linux/freezer.h>
#include <linux/kernel.h>
#include <linux/sched/clock.h>
#include <linux/llist.h>
#include <linux/log2.h>
#include <linux/percpu.h>
#include <linux/preempt.h>
#include <linux/random.h>
#include <linux/ratelimit.h>
#include <linux/slab.h>
#include <linux/sort.h>
#include <linux/version.h>
#include <linux/vmalloc.h>
#include <linux/workqueue.h>

#include "closure.h"
#include "mean_and_variance.h"

#include "darray.h"
#include "time_stats.h"

struct closure;

#ifdef CONFIG_BCACHEFS_DEBUG
#define EBUG_ON(cond)		BUG_ON(cond)
#else
#define EBUG_ON(cond)
#endif

#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
#define CPU_BIG_ENDIAN		0
#elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
#define CPU_BIG_ENDIAN		1
#endif

/* type hackery */

#define type_is_exact(_val, _type)					\
	__builtin_types_compatible_p(typeof(_val), _type)

#define type_is(_val, _type)						\
	(__builtin_types_compatible_p(typeof(_val), _type) ||		\
	 __builtin_types_compatible_p(typeof(_val), const _type))

#if defined(__KERNEL__) && LINUX_VERSION_CODE < KERNEL_VERSION(6,18,0)
static inline struct bio_vec *bio_inline_vecs(struct bio *bio)
{
	return (struct bio_vec *)(bio + 1);
}
#endif

/*
 * 7.1 introduced bdev_rot() and removed bdev_nonrot(). Shim bdev_rot for
 * older kernels and userspace so call sites can always use bdev_rot.
 */
#if !defined(__KERNEL__) || LINUX_VERSION_CODE < KERNEL_VERSION(7,0,0)
static inline bool bdev_rot(struct block_device *bdev)
{
	return !bdev_nonrot(bdev);
}
#endif

DEFINE_FREE(bio_put, struct bio *, if (_T) bio_put(_T))

/*
 * Number of bvecs needed to describe [p, p+len) in a bio, matching how
 * bch2_bio_map() will add it: physically contiguous buffers take one bvec,
 * vmalloc buffers take one bvec per page.
 */
static inline size_t buf_nr_bvecs(void *p, size_t len)
{
	return is_vmalloc_addr(p)
		? DIV_ROUND_UP(len + ((unsigned long) p & (PAGE_SIZE - 1)),
			       PAGE_SIZE)
		: 1;
}

static inline void *bch2_kvmalloc_noprof(size_t n, gfp_t flags)
{
#if LINUX_VERSION_CODE < KERNEL_VERSION(6,18,0)
	void *p = unlikely(n >= INT_MAX)
		? vmalloc_noprof(n)
		: kvmalloc_noprof(n, flags & ~__GFP_ZERO);
#else
	void *p = unlikely(n >= INT_MAX)
		? vmalloc_noprof(n)
		: kvmalloc_node_align_noprof(n, 1, flags & ~__GFP_ZERO, NUMA_NO_NODE);
#endif
	if (p && (flags & __GFP_ZERO))
		memset(p, 0, n);
	return p;
}
#define bch2_kvmalloc(...)			alloc_hooks(bch2_kvmalloc_noprof(__VA_ARGS__))

#define init_heap(heap, _size, gfp)					\
({									\
	(heap)->nr = 0;						\
	(heap)->size = (_size);						\
	(heap)->data = kvmalloc((heap)->size * sizeof((heap)->data[0]),\
				 (gfp));				\
})

#define free_heap(heap)							\
do {									\
	kvfree((heap)->data);						\
	(heap)->data = NULL;						\
} while (0)

#define ANYSINT_MAX(t)							\
	((((t) 1 << (sizeof(t) * 8 - 2)) - (t) 1) * (t) 2 + (t) 1)

#include "printbuf.h"

#define prt_vprintf(_out, ...)		bch2_prt_vprintf(_out, __VA_ARGS__)
#define prt_printf(_out, ...)		bch2_prt_printf(_out, __VA_ARGS__)
#define printbuf_str(_buf)		bch2_printbuf_str(_buf)
#define printbuf_exit(_buf)		bch2_printbuf_exit(_buf)

#define printbuf_tabstops_reset(_buf)	bch2_printbuf_tabstops_reset(_buf)
#define printbuf_tabstop_pop(_buf)	bch2_printbuf_tabstop_pop(_buf)
#define printbuf_tabstop_push(_buf, _n)	bch2_printbuf_tabstop_push(_buf, _n)

#define printbuf_indent_add(_out, _n)	bch2_printbuf_indent_add(_out, _n)
#define printbuf_indent_add_nextline(_out, _n)	bch2_printbuf_indent_add_nextline(_out, _n)
#define printbuf_indent_sub(_out, _n)	bch2_printbuf_indent_sub(_out, _n)

#define prt_newline(_out)		bch2_prt_newline(_out)
#define prt_tab(_out)			bch2_prt_tab(_out)
#define prt_tab_rjust(_out)		bch2_prt_tab_rjust(_out)

#define prt_bytes_indented(...)		bch2_prt_bytes_indented(__VA_ARGS__)
#define prt_u64(_out, _v)		prt_printf(_out, "%llu", (u64) (_v))
#define prt_human_readable_u64(...)	bch2_prt_human_readable_u64(__VA_ARGS__)
#define prt_human_readable_s64(...)	bch2_prt_human_readable_s64(__VA_ARGS__)
#define prt_units_u64(...)		bch2_prt_units_u64(__VA_ARGS__)
#define prt_units_s64(...)		bch2_prt_units_s64(__VA_ARGS__)
#define prt_string_option(...)		bch2_prt_string_option(__VA_ARGS__)
#define prt_bitflags(...)		bch2_prt_bitflags(__VA_ARGS__)
#define prt_bitflags_vector(...)	bch2_prt_bitflags_vector(__VA_ARGS__)

void bch2_pr_time_units(struct printbuf *, u64);
void bch2_prt_datetime(struct printbuf *, time64_t);

#ifdef __KERNEL__
static inline void uuid_unparse_lower(u8 *uuid, char *out)
{
	sprintf(out, "%pUb", uuid);
}
#else
#include <uuid/uuid.h>
#endif

static inline void pr_uuid(struct printbuf *out, u8 *uuid)
{
	char uuid_str[40];

	uuid_unparse_lower(uuid, uuid_str);
	prt_printf(out, "%s", uuid_str);
}

int bch2_strtoint_h(const char *, int *);
int bch2_strtouint_h(const char *, unsigned int *);
int bch2_strtoll_h(const char *, long long *);
int bch2_strtoull_h(const char *, unsigned long long *);
int bch2_strtou64_h(const char *, u64 *);

static inline int bch2_strtol_h(const char *cp, long *res)
{
#if BITS_PER_LONG == 32
	return bch2_strtoint_h(cp, (int *) res);
#else
	return bch2_strtoll_h(cp, (long long *) res);
#endif
}

static inline int bch2_strtoul_h(const char *cp, long *res)
{
#if BITS_PER_LONG == 32
	return bch2_strtouint_h(cp, (unsigned int *) res);
#else
	return bch2_strtoull_h(cp, (unsigned long long *) res);
#endif
}

#define strtoi_h(cp, res)						\
	( type_is(*res, int)		? bch2_strtoint_h(cp, (void *) res)\
	: type_is(*res, long)		? bch2_strtol_h(cp, (void *) res)\
	: type_is(*res, long long)	? bch2_strtoll_h(cp, (void *) res)\
	: type_is(*res, unsigned)	? bch2_strtouint_h(cp, (void *) res)\
	: type_is(*res, unsigned long)	? bch2_strtoul_h(cp, (void *) res)\
	: type_is(*res, unsigned long long) ? bch2_strtoull_h(cp, (void *) res)\
	: -EINVAL)

#define strtoul_safe(cp, var)						\
({									\
	unsigned long _v;						\
	int _r = kstrtoul(cp, 10, &_v);					\
	if (!_r)							\
		var = _v;						\
	_r;								\
})

#define strtoul_safe_clamp(cp, var, min, max)				\
({									\
	unsigned long _v;						\
	int _r = kstrtoul(cp, 10, &_v);					\
	if (!_r)							\
		var = clamp_t(typeof(var), _v, min, max);		\
	_r;								\
})

#define strtoul_safe_restrict(cp, var, min, max)			\
({									\
	unsigned long _v;						\
	int _r = kstrtoul(cp, 10, &_v);					\
	if (!_r && _v >= min && _v <= max)				\
		var = _v;						\
	else								\
		_r = -EINVAL;						\
	_r;								\
})

#define snprint(out, var)						\
	prt_printf(out,							\
		   type_is(var, int)		? "%i\n"		\
		 : type_is(var, unsigned)	? "%u\n"		\
		 : type_is(var, long)		? "%li\n"		\
		 : type_is(var, unsigned long)	? "%lu\n"		\
		 : type_is(var, s64)		? "%lli\n"		\
		 : type_is(var, u64)		? "%llu\n"		\
		 : type_is(var, char *)		? "%s\n"		\
		 : "%i\n", var)

bool bch2_is_zero(const void *, size_t);

u64 bch2_read_flag_list(const char *, const char * const[]);

void bch2_prt_u64_base2_nbits(struct printbuf *, u64, unsigned);
void bch2_prt_u64_base2(struct printbuf *, u64);

void bch2_print_string_as_lines(const char *, const char *);

DEFINE_DARRAY_NAMED(bch_stacktrace, unsigned long);

int bch2_save_backtrace(bch_stacktrace *stack, struct task_struct *, unsigned, gfp_t);
void bch2_prt_backtrace(struct printbuf *, bch_stacktrace *);
int bch2_prt_task_backtrace(struct printbuf *, struct task_struct *, unsigned, gfp_t);

static inline void prt_bdevname(struct printbuf *out, struct block_device *bdev)
{
#ifdef __KERNEL__
	prt_printf(out, "%pg", bdev);
#else
	prt_str(out, bdev->name);
#endif
}

void bch2_time_stats_to_text(struct printbuf *, struct bch2_time_stats *);
void bch2_time_stats_json_to_text(struct printbuf *, struct bch2_time_stats *,
				  const char *epoch_name, unsigned int flags);

#define ewma_add(ewma, val, weight)					\
({									\
	typeof(ewma) _ewma = (ewma);					\
	typeof(weight) _weight = (weight);				\
									\
	(((_ewma << _weight) - _ewma) + (val)) >> _weight;		\
})

struct bch_ratelimit {
	/* Next time we want to do some work, in nanoseconds */
	u64			next;

	/*
	 * Rate at which we want to do work, in units per nanosecond
	 * The units here correspond to the units passed to
	 * bch2_ratelimit_increment()
	 */
	unsigned		rate;
};

static inline void bch2_ratelimit_reset(struct bch_ratelimit *d)
{
	d->next = local_clock();
}

u64 bch2_ratelimit_delay(struct bch_ratelimit *);
void bch2_ratelimit_increment(struct bch_ratelimit *, u64);

struct bch_pd_controller {
	struct bch_ratelimit	rate;
	unsigned long		last_update;

	s64			last_actual;
	s64			smoothed_derivative;

	unsigned		p_term_inverse;
	unsigned		d_smooth;
	unsigned		d_term;

	/* for exporting to sysfs (no effect on behavior) */
	s64			last_derivative;
	s64			last_proportional;
	s64			last_change;
	s64			last_target;

	/*
	 * If true, the rate will not increase if bch2_ratelimit_delay()
	 * is not being called often enough.
	 */
	bool			backpressure;
};

void bch2_pd_controller_update(struct bch_pd_controller *, s64, s64, int);
void bch2_pd_controller_init(struct bch_pd_controller *);
void bch2_pd_controller_debug_to_text(struct printbuf *, struct bch_pd_controller *);

#define sysfs_pd_controller_attribute(name)				\
	rw_attribute(name##_rate);					\
	rw_attribute(name##_rate_bytes);				\
	rw_attribute(name##_rate_d_term);				\
	rw_attribute(name##_rate_p_term_inverse);			\
	read_attribute(name##_rate_debug)

#define sysfs_pd_controller_files(name)					\
	&sysfs_##name##_rate,						\
	&sysfs_##name##_rate_bytes,					\
	&sysfs_##name##_rate_d_term,					\
	&sysfs_##name##_rate_p_term_inverse,				\
	&sysfs_##name##_rate_debug

#define sysfs_pd_controller_show(name, var)				\
do {									\
	sysfs_hprint(name##_rate,		(var)->rate.rate);	\
	sysfs_print(name##_rate_bytes,		(var)->rate.rate);	\
	sysfs_print(name##_rate_d_term,		(var)->d_term);		\
	sysfs_print(name##_rate_p_term_inverse,	(var)->p_term_inverse);	\
									\
	if (attr == &sysfs_##name##_rate_debug)				\
		bch2_pd_controller_debug_to_text(out, var);		\
} while (0)

#define sysfs_pd_controller_store(name, var)				\
do {									\
	sysfs_strtoul_clamp(name##_rate,				\
			    (var)->rate.rate, 1, UINT_MAX);		\
	sysfs_strtoul_clamp(name##_rate_bytes,				\
			    (var)->rate.rate, 1, UINT_MAX);		\
	sysfs_strtoul(name##_rate_d_term,	(var)->d_term);		\
	sysfs_strtoul_clamp(name##_rate_p_term_inverse,			\
			    (var)->p_term_inverse, 1, INT_MAX);		\
} while (0)

#define container_of_or_null(ptr, type, member)				\
({									\
	typeof(ptr) _ptr = ptr;						\
	_ptr ? container_of(_ptr, type, member) : NULL;			\
})

static inline struct list_head *list_pop(struct list_head *head)
{
	if (list_empty(head))
		return NULL;

	struct list_head *ret = head->next;
	list_del_init(ret);
	return ret;
}

#define list_pop_entry(head, type, member)		\
	container_of_or_null(list_pop(head), type, member)

/* Does linear interpolation between powers of two */
static inline unsigned fract_exp_two(unsigned x, unsigned fract_bits)
{
	unsigned fract = x & ~(~0 << fract_bits);

	x >>= fract_bits;
	x   = 1 << x;
	x  += (x * fract) >> fract_bits;

	return x;
}

void bch2_bio_map(struct bio *bio, void *base, size_t);
struct bio *bch2_bio_map_and_chain(struct block_device *, void *, size_t,
				   sector_t, blk_opf_t, gfp_t,
				   struct bio_set *);
int bch2_bio_submit_buf_wait(struct block_device *, void *, size_t, sector_t, blk_opf_t);
int bch2_bio_alloc_pages(struct bio *, unsigned, size_t, gfp_t);

#define closure_bio_submit(bio, cl)					\
do {									\
	closure_get(cl);						\
	submit_bio(bio);						\
} while (0)

#define kthread_wait(cond)						\
({									\
	int _ret = 0;							\
									\
	while (1) {							\
		set_current_state(TASK_INTERRUPTIBLE);			\
		if (kthread_should_stop()) {				\
			_ret = -1;					\
			break;						\
		}							\
									\
		if (cond)						\
			break;						\
									\
		schedule();						\
	}								\
	set_current_state(TASK_RUNNING);				\
	_ret;								\
})

#define kthread_wait_freezable(cond)					\
({									\
	int _ret = 0;							\
	while (1) {							\
		set_current_state(TASK_INTERRUPTIBLE);			\
		if (kthread_should_stop()) {				\
			_ret = -1;					\
			break;						\
		}							\
									\
		if (cond)						\
			break;						\
									\
		schedule();						\
		try_to_freeze();					\
	}								\
	set_current_state(TASK_RUNNING);				\
	_ret;								\
})

u64 bch2_get_random_u64_below(u64);

/*
 * All-ones mask of width @bits, defined for the full range 0..64 — unlike
 * (1ULL << bits) - 1 (UB at 64) or ~0ULL >> (64 - bits) (UB at 0).
 * Compiles branchless (cmov).
 */
static inline u64 u64_bitmask(unsigned bits)
{
	return bits ? ~0ULL >> (64 - bits) : 0;
}

void memcpy_to_bio(struct bio *, struct bvec_iter, const void *);
void memcpy_from_bio(void *, struct bio *, struct bvec_iter);

#ifdef CONFIG_BCACHEFS_DEBUG
void bch2_corrupt_bio(struct bio *);

static inline void bch2_maybe_corrupt_bio(struct bio *bio, unsigned ratio)
{
	if (ratio && !get_random_u32_below(ratio))
		bch2_corrupt_bio(bio);
}
#else
#define bch2_maybe_corrupt_bio(...)	do {} while (0)
#endif

void bch2_bio_to_text(struct printbuf *, struct bio *);

static inline void __memcpy_u64s(void *dst, const void *src,
				 unsigned u64s)
{
	unsafe_memcpy(dst, src, u64s * 8,
		      "dst is a u64s array sized by the caller, not a single field");
}

/*
 * For small, bounded copies (a key, a handful of u64s): the open-coded loop is
 * tighter codegen than a memcpy() call / its inline expansion. For larger or
 * variable-size copies (key + value, bulk), use memcpy_u64s() so we get the
 * fast-string path.
 */
static inline void memcpy_u64s_small(void *dst, const void *src,
				     unsigned u64s)
{
	u64 *d = dst;
	const u64 *s = src;

	while (u64s--)
		*d++ = *s++;
}

static inline void memcpy_u64s(void *dst, const void *src,
			       unsigned u64s)
{
	EBUG_ON(!(dst >= src + u64s * sizeof(u64) ||
		 dst + u64s * sizeof(u64) <= src));

	__memcpy_u64s(dst, src, u64s);
}

static inline void memset_u64s_small(void *dst, u64 c,
			       unsigned u64s)
{
	u64 *d = dst;

	while (u64s--)
		*d++ = c;
}

/*
 * Fortify can't see the real object size for u64s-array copies, same as
 * __memcpy_u64s() - but there's no unsafe_memmove(), so go underneath
 * fortify by hand:
 */
static inline void __memmove_u64s(void *dst, const void *src,
				  unsigned u64s)
{
#ifdef _LINUX_FORTIFY_STRING_H_
	__underlying_memmove(dst, src, u64s * 8);
#else
	memmove(dst, src, u64s * 8);
#endif
}

static inline void memmove_u64s_down(void *dst, const void *src,
				     unsigned u64s)
{
	EBUG_ON(dst > src);

	__memmove_u64s(dst, src, u64s);
}

static inline void __memmove_u64s_down_small(void *dst, const void *src,
				       unsigned u64s)
{
	/* dst <= src: a forward copy can't clobber unread source */
	memcpy_u64s_small(dst, src, u64s);
}

static inline void memmove_u64s_down_small(void *dst, const void *src,
				     unsigned u64s)
{
	EBUG_ON(dst > src);

	__memmove_u64s_down_small(dst, src, u64s);
}

static inline void __memmove_u64s_up_small(void *_dst, const void *_src,
					   unsigned u64s)
{
	u64 *dst = (u64 *) _dst + u64s;
	u64 *src = (u64 *) _src + u64s;

	while (u64s--)
		*--dst = *--src;
}

static inline void memmove_u64s_up_small(void *dst, const void *src,
					 unsigned u64s)
{
	EBUG_ON(dst < src);

	__memmove_u64s_up_small(dst, src, u64s);
}

static inline void memmove_u64s_up(void *dst, void *src,
				   unsigned u64s)
{
	EBUG_ON(dst < src);

	__memmove_u64s(dst, src, u64s);
}

static inline void memmove_u64s(void *dst, void *src,
				unsigned u64s)
{
	__memmove_u64s(dst, src, u64s);
}

/* Set the last few bytes up to a u64 boundary given an offset into a buffer. */
static inline void memset_u64s_tail(void *s, int c, unsigned bytes)
{
	while (bytes & 7) {
		((char *) s)[bytes] = c;
		bytes++;
	}
}

/* just the memmove, doesn't update @_nr */
#define __array_insert_item(_array, _nr, _pos)				\
	memmove(&(_array)[(_pos) + 1],					\
		&(_array)[(_pos)],					\
		sizeof((_array)[0]) * ((_nr) - (_pos)))

#define array_insert_item(_array, _nr, _pos, _new_item)			\
do {									\
	__array_insert_item(_array, _nr, _pos);				\
	(_nr)++;							\
	(_array)[(_pos)] = (_new_item);					\
} while (0)

#define array_remove_items(_array, _nr, _pos, _nr_to_remove)		\
do {									\
	(_nr) -= (_nr_to_remove);					\
	memmove(&(_array)[(_pos)],					\
		&(_array)[(_pos) + (_nr_to_remove)],			\
		sizeof((_array)[0]) * ((_nr) - (_pos)));		\
} while (0)

#define array_remove_item(_array, _nr, _pos)				\
	array_remove_items(_array, _nr, _pos, 1)

static inline void __move_gap(void *array, size_t element_size,
			      size_t nr, size_t size,
			      size_t old_gap, size_t new_gap)
{
	size_t gap_end = old_gap + size - nr;

	if (new_gap < old_gap) {
		size_t move = old_gap - new_gap;

		memmove(array + element_size * (gap_end - move),
			array + element_size * (old_gap - move),
				element_size * move);
	} else if (new_gap > old_gap) {
		size_t move = new_gap - old_gap;

		memmove(array + element_size * old_gap,
			array + element_size * gap_end,
				element_size * move);
	}
}

/* Move the gap in a gap buffer: */
#define move_gap(_d, _new_gap)						\
do {									\
	BUG_ON(_new_gap > (_d)->nr);					\
	BUG_ON((_d)->gap > (_d)->nr);					\
									\
	__move_gap((_d)->data, sizeof((_d)->data[0]),			\
		   (_d)->nr, (_d)->size, (_d)->gap, _new_gap);		\
	(_d)->gap = _new_gap;						\
} while (0)

#define bubble_sort(_base, _nr, _cmp)					\
do {									\
	ssize_t _i, _last;						\
	bool _swapped = true;						\
									\
	for (_last= (ssize_t) (_nr) - 1; _last > 0 && _swapped; --_last) {\
		_swapped = false;					\
		for (_i = 0; _i < _last; _i++)				\
			if (_cmp((_base)[_i], (_base)[_i + 1]) > 0) {	\
				swap((_base)[_i], (_base)[_i + 1]);	\
				_swapped = true;			\
			}						\
	}								\
} while (0)

#define per_cpu_sum(_p)							\
({									\
	TYPEOF_UNQUAL(*_p) _ret = 0;					\
									\
	int cpu;							\
	for_each_possible_cpu(cpu)					\
		_ret += *per_cpu_ptr(_p, cpu);				\
	_ret;								\
})

static inline u64 percpu_u64_get(u64 __percpu *src)
{
	return per_cpu_sum(src);
}

static inline void percpu_u64_set(u64 __percpu *dst, u64 src)
{
	int cpu;

	for_each_possible_cpu(cpu)
		*per_cpu_ptr(dst, cpu) = 0;
	this_cpu_write(*dst, src);
}

static inline void acc_u64s(u64 *acc, const u64 *src, unsigned nr)
{
	for (unsigned i = 0; i < nr; i++)
		acc[i] += src[i];
}

static inline void acc_u64s_percpu(u64 *acc, const u64 __percpu *src,
				   unsigned nr)
{
	int cpu;

	for_each_possible_cpu(cpu)
		acc_u64s(acc, per_cpu_ptr(src, cpu), nr);
}

static inline void percpu_memset(void __percpu *p, int c, size_t bytes)
{
	int cpu;

	for_each_possible_cpu(cpu)
		memset(per_cpu_ptr(p, cpu), c, bytes);
}

u64 *bch2_acc_percpu_u64s(u64 __percpu *, unsigned);

static inline int u8_cmp(u8 l, u8 r)
{
	return cmp_int(l, r);
}

static inline int cmp_le32(__le32 l, __le32 r)
{
	return cmp_int(le32_to_cpu(l), le32_to_cpu(r));
}

#include <linux/uuid.h>

static inline bool qstr_eq(const struct qstr l, const struct qstr r)
{
	return l.len == r.len && !memcmp(l.name, r.name, l.len);
}

int bch2_split_devs(const char *, darray_const_str *);

#ifdef __KERNEL__

__must_check
static inline int copy_to_user_errcode(void __user *to, const void *from, unsigned long n)
{
	return copy_to_user(to, from, n) ? -EFAULT : 0;
}

__must_check
static inline int copy_from_user_errcode(void *to, const void __user *from, unsigned long n)
{
	return copy_from_user(to, from, n) ? -EFAULT : 0;
}

#endif

static inline void mod_bit(long nr, volatile unsigned long *addr, bool v)
{
	if (v)
		set_bit(nr, addr);
	else
		clear_bit(nr, addr);
}

static inline void __set_bit_le64(size_t bit, __le64 *addr)
{
	addr[bit / 64] |= cpu_to_le64(BIT_ULL(bit % 64));
}

static inline void __clear_bit_le64(size_t bit, __le64 *addr)
{
	addr[bit / 64] &= ~cpu_to_le64(BIT_ULL(bit % 64));
}

static inline bool test_bit_le64(size_t bit, __le64 *addr)
{
	return (addr[bit / 64] & cpu_to_le64(BIT_ULL(bit % 64))) != 0;
}

static inline bool __test_and_set_bit_le64(size_t bit, __le64 *addr)
{
	bool ret = test_bit_le64(bit, addr);
	__set_bit_le64(bit, addr);
	return ret;
}

static inline void memcpy_swab(void *_dst, void *_src, size_t len)
{
	u8 *dst = _dst + len;
	u8 *src = _src;

	while (len--)
		*--dst = *src++;
}

#define set_flags(_map, _in, _out)					\
do {									\
	unsigned _i;							\
									\
	for (_i = 0; _i < ARRAY_SIZE(_map); _i++)			\
		if ((_in) & (1 << _i))					\
			(_out) |= _map[_i];				\
		else							\
			(_out) &= ~_map[_i];				\
} while (0)

#define map_flags(_map, _in)						\
({									\
	unsigned _out = 0;						\
									\
	set_flags(_map, _in, _out);					\
	_out;								\
})

#define map_flags_rev(_map, _in)					\
({									\
	unsigned _i, _out = 0;						\
									\
	for (_i = 0; _i < ARRAY_SIZE(_map); _i++)			\
		if ((_in) & _map[_i]) {					\
			(_out) |= 1 << _i;				\
			(_in) &= ~_map[_i];				\
		}							\
	(_out);								\
})

#define map_defined(_map)						\
({									\
	unsigned _in = ~0;						\
									\
	map_flags_rev(_map, _in);					\
})

#define try(_do)							\
do {									\
	typeof(_do) _ret = (_do);					\
	if (unlikely(_ret))						\
		return _ret;						\
} while (0)

#define errptr_try(_do)							\
({									\
	typeof(_do) _ret = (_do);					\
	if (IS_ERR(_ret))						\
		return PTR_ERR(_ret);					\
	_ret;								\
})

#include <linux/sched/mm.h>

struct memalloc_flags { unsigned flags; };

DEFINE_CLASS(memalloc_flags, struct memalloc_flags,
	     memalloc_flags_restore(_T.flags),
	     (struct memalloc_flags) { memalloc_flags_save(_flags) },
	     unsigned _flags)
__DEFINE_CLASS_IS_CONDITIONAL(memalloc_flags, false);

static inline void *class_memalloc_flags_lock_ptr(class_memalloc_flags_t *_T)
{
	return _T;
}

#if !defined(__KERNEL__) || LINUX_VERSION_CODE >= KERNEL_VERSION(6,19,0)
void *mempool_kvmalloc(gfp_t gfp_mask, void *pool_data);
void mempool_kvfree(void *element, void *pool_data);

static inline int mempool_init_kvmalloc_pool(mempool_t *pool, int min_nr, size_t size)
{
        return mempool_init(pool, min_nr, mempool_kvmalloc, mempool_kvfree, (void *) size);
}

static inline mempool_t *mempool_create_kvmalloc_pool(int min_nr, size_t size)
{
        return mempool_create(min_nr, mempool_kvmalloc, mempool_kvfree, (void *) size);
}
#endif

#include <linux/wait_bit.h>

int bch2_bit_wait_io_timeout(struct wait_bit_key *, int);

/*
 * wait_on_bit_io_timeout() - missing from <linux/wait_bit.h>; same as
 * wait_on_bit_timeout() but uses io_schedule_timeout() so the wait is
 * accounted as iowait.
 */
static inline int wait_on_bit_io_timeout(unsigned long *word, int bit,
					 unsigned mode, unsigned long timeout)
{
	might_sleep();
	if (!test_bit_acquire(bit, word))
		return 0;
	return out_of_line_wait_on_bit_timeout(word, bit,
					       bch2_bit_wait_io_timeout,
					       mode, timeout);
}

/*
 * bch2_alloc_percpu_init(): run init() on every per-cpu instance of a
 * dynamically-allocated percpu variable.
 *
 * Kernel: iterates for_each_possible_cpu and calls init() once per cpu
 * at allocation time.
 *
 * Userspace: alloc_percpu() returns an offset into a per-thread chunk;
 * threads come and go dynamically, so init() must also be called for
 * each thread that's spawned later. The userspace shim stashes the
 * (init, ctx) pair alongside the percpu variable so it can call init()
 * for every existing chunk now and every future chunk at thread
 * creation time.
 *
 * The init function takes (per-instance ptr, caller ctx, cpu id).
 */
#ifdef __KERNEL__
#define bch2_alloc_percpu_init(_pcv, _init, _ctx)			\
do {									\
	int _cpu;							\
	for_each_possible_cpu(_cpu)					\
		(_init)(per_cpu_ptr((_pcv), _cpu), (_ctx), _cpu);	\
} while (0)
#else
void __bch2_alloc_percpu_init(void *pcv,
			      void (*init)(void *, void *, unsigned),
			      void *ctx);
#define bch2_alloc_percpu_init(_pcv, _init, _ctx)			\
	__bch2_alloc_percpu_init((_pcv),				\
		(void (*)(void *, void *, unsigned))(_init), (_ctx))
#endif

static inline u64 system_totalram_bytes(void)
{
	struct sysinfo i;
	si_meminfo(&i);

	return i.totalram * i.mem_unit;
}

#endif /* _BCACHEFS_UTIL_H */
