]> git.sesse.net Git - bcachefs-tools-debian/blobdiff - c_src/libbcachefs/util.h
move Rust sources to top level, C sources into c_src
[bcachefs-tools-debian] / c_src / libbcachefs / util.h
diff --git a/c_src/libbcachefs/util.h b/c_src/libbcachefs/util.h
new file mode 100644 (file)
index 0000000..c75fc31
--- /dev/null
@@ -0,0 +1,878 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _BCACHEFS_UTIL_H
+#define _BCACHEFS_UTIL_H
+
+#include <linux/bio.h>
+#include <linux/blkdev.h>
+#include <linux/closure.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/ratelimit.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/workqueue.h>
+
+#include "mean_and_variance.h"
+
+#include "darray.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))
+
+/* Userspace doesn't align allocations as nicely as the kernel allocators: */
+static inline size_t buf_pages(void *p, size_t len)
+{
+       return DIV_ROUND_UP(len +
+                           ((unsigned long) p & (PAGE_SIZE - 1)),
+                           PAGE_SIZE);
+}
+
+static inline void vpfree(void *p, size_t size)
+{
+       if (is_vmalloc_addr(p))
+               vfree(p);
+       else
+               free_pages((unsigned long) p, get_order(size));
+}
+
+static inline void *vpmalloc(size_t size, gfp_t gfp_mask)
+{
+       return (void *) __get_free_pages(gfp_mask|__GFP_NOWARN,
+                                        get_order(size)) ?:
+               __vmalloc(size, gfp_mask);
+}
+
+static inline void kvpfree(void *p, size_t size)
+{
+       if (size < PAGE_SIZE)
+               kfree(p);
+       else
+               vpfree(p, size);
+}
+
+static inline void *kvpmalloc(size_t size, gfp_t gfp_mask)
+{
+       return size < PAGE_SIZE
+               ? kmalloc(size, gfp_mask)
+               : vpmalloc(size, gfp_mask);
+}
+
+int mempool_init_kvpmalloc_pool(mempool_t *, int, size_t);
+
+#define HEAP(type)                                                     \
+struct {                                                               \
+       size_t size, used;                                              \
+       type *data;                                                     \
+}
+
+#define DECLARE_HEAP(type, name) HEAP(type) name
+
+#define init_heap(heap, _size, gfp)                                    \
+({                                                                     \
+       (heap)->used = 0;                                               \
+       (heap)->size = (_size);                                         \
+       (heap)->data = kvpmalloc((heap)->size * sizeof((heap)->data[0]),\
+                                (gfp));                                \
+})
+
+#define free_heap(heap)                                                        \
+do {                                                                   \
+       kvpfree((heap)->data, (heap)->size * sizeof((heap)->data[0]));  \
+       (heap)->data = NULL;                                            \
+} while (0)
+
+#define heap_set_backpointer(h, i, _fn)                                        \
+do {                                                                   \
+       void (*fn)(typeof(h), size_t) = _fn;                            \
+       if (fn)                                                         \
+               fn(h, i);                                               \
+} while (0)
+
+#define heap_swap(h, i, j, set_backpointer)                            \
+do {                                                                   \
+       swap((h)->data[i], (h)->data[j]);                               \
+       heap_set_backpointer(h, i, set_backpointer);                    \
+       heap_set_backpointer(h, j, set_backpointer);                    \
+} while (0)
+
+#define heap_peek(h)                                                   \
+({                                                                     \
+       EBUG_ON(!(h)->used);                                            \
+       (h)->data[0];                                                   \
+})
+
+#define heap_full(h)   ((h)->used == (h)->size)
+
+#define heap_sift_down(h, i, cmp, set_backpointer)                     \
+do {                                                                   \
+       size_t _c, _j = i;                                              \
+                                                                       \
+       for (; _j * 2 + 1 < (h)->used; _j = _c) {                       \
+               _c = _j * 2 + 1;                                        \
+               if (_c + 1 < (h)->used &&                               \
+                   cmp(h, (h)->data[_c], (h)->data[_c + 1]) >= 0)      \
+                       _c++;                                           \
+                                                                       \
+               if (cmp(h, (h)->data[_c], (h)->data[_j]) >= 0)          \
+                       break;                                          \
+               heap_swap(h, _c, _j, set_backpointer);                  \
+       }                                                               \
+} while (0)
+
+#define heap_sift_up(h, i, cmp, set_backpointer)                       \
+do {                                                                   \
+       while (i) {                                                     \
+               size_t p = (i - 1) / 2;                                 \
+               if (cmp(h, (h)->data[i], (h)->data[p]) >= 0)            \
+                       break;                                          \
+               heap_swap(h, i, p, set_backpointer);                    \
+               i = p;                                                  \
+       }                                                               \
+} while (0)
+
+#define __heap_add(h, d, cmp, set_backpointer)                         \
+({                                                                     \
+       size_t _i = (h)->used++;                                        \
+       (h)->data[_i] = d;                                              \
+       heap_set_backpointer(h, _i, set_backpointer);                   \
+                                                                       \
+       heap_sift_up(h, _i, cmp, set_backpointer);                      \
+       _i;                                                             \
+})
+
+#define heap_add(h, d, cmp, set_backpointer)                           \
+({                                                                     \
+       bool _r = !heap_full(h);                                        \
+       if (_r)                                                         \
+               __heap_add(h, d, cmp, set_backpointer);                 \
+       _r;                                                             \
+})
+
+#define heap_add_or_replace(h, new, cmp, set_backpointer)              \
+do {                                                                   \
+       if (!heap_add(h, new, cmp, set_backpointer) &&                  \
+           cmp(h, new, heap_peek(h)) >= 0) {                           \
+               (h)->data[0] = new;                                     \
+               heap_set_backpointer(h, 0, set_backpointer);            \
+               heap_sift_down(h, 0, cmp, set_backpointer);             \
+       }                                                               \
+} while (0)
+
+#define heap_del(h, i, cmp, set_backpointer)                           \
+do {                                                                   \
+       size_t _i = (i);                                                \
+                                                                       \
+       BUG_ON(_i >= (h)->used);                                        \
+       (h)->used--;                                                    \
+       if ((_i) < (h)->used) {                                         \
+               heap_swap(h, _i, (h)->used, set_backpointer);           \
+               heap_sift_up(h, _i, cmp, set_backpointer);              \
+               heap_sift_down(h, _i, cmp, set_backpointer);            \
+       }                                                               \
+} while (0)
+
+#define heap_pop(h, d, cmp, set_backpointer)                           \
+({                                                                     \
+       bool _r = (h)->used;                                            \
+       if (_r) {                                                       \
+               (d) = (h)->data[0];                                     \
+               heap_del(h, 0, cmp, set_backpointer);                   \
+       }                                                               \
+       _r;                                                             \
+})
+
+#define heap_resort(heap, cmp, set_backpointer)                                \
+do {                                                                   \
+       ssize_t _i;                                                     \
+       for (_i = (ssize_t) (heap)->used / 2 -  1; _i >= 0; --_i)       \
+               heap_sift_down(heap, _i, cmp, set_backpointer);         \
+} 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_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(char *, const char * const[]);
+
+void bch2_prt_u64_binary(struct printbuf *, u64, unsigned);
+
+void bch2_print_string_as_lines(const char *prefix, const char *lines);
+
+typedef DARRAY(unsigned long) bch_stacktrace;
+int bch2_save_backtrace(bch_stacktrace *stack, struct task_struct *, unsigned);
+void bch2_prt_backtrace(struct printbuf *, bch_stacktrace *);
+int bch2_prt_task_backtrace(struct printbuf *, struct task_struct *, unsigned);
+
+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
+}
+
+#define NR_QUANTILES   15
+#define QUANTILE_IDX(i)        inorder_to_eytzinger0(i, NR_QUANTILES)
+#define QUANTILE_FIRST eytzinger0_first(NR_QUANTILES)
+#define QUANTILE_LAST  eytzinger0_last(NR_QUANTILES)
+
+struct bch2_quantiles {
+       struct bch2_quantile_entry {
+               u64     m;
+               u64     step;
+       }               entries[NR_QUANTILES];
+};
+
+struct bch2_time_stat_buffer {
+       unsigned        nr;
+       struct bch2_time_stat_buffer_entry {
+               u64     start;
+               u64     end;
+       }               entries[32];
+};
+
+struct bch2_time_stats {
+       spinlock_t      lock;
+       /* all fields are in nanoseconds */
+       u64             min_duration;
+       u64             max_duration;
+       u64             total_duration;
+       u64             max_freq;
+       u64             min_freq;
+       u64             last_event;
+       struct bch2_quantiles quantiles;
+
+       struct mean_and_variance          duration_stats;
+       struct mean_and_variance_weighted duration_stats_weighted;
+       struct mean_and_variance          freq_stats;
+       struct mean_and_variance_weighted freq_stats_weighted;
+       struct bch2_time_stat_buffer __percpu *buffer;
+};
+
+#ifndef CONFIG_BCACHEFS_NO_LATENCY_ACCT
+void __bch2_time_stats_update(struct bch2_time_stats *stats, u64, u64);
+
+static inline void bch2_time_stats_update(struct bch2_time_stats *stats, u64 start)
+{
+       __bch2_time_stats_update(stats, start, local_clock());
+}
+
+static inline bool track_event_change(struct bch2_time_stats *stats,
+                                     u64 *start, bool v)
+{
+       if (v != !!*start) {
+               if (!v) {
+                       bch2_time_stats_update(stats, *start);
+                       *start = 0;
+               } else {
+                       *start = local_clock() ?: 1;
+                       return true;
+               }
+       }
+
+       return false;
+}
+#else
+static inline void __bch2_time_stats_update(struct bch2_time_stats *stats, u64 start, u64 end) {}
+static inline void bch2_time_stats_update(struct bch2_time_stats *stats, u64 start) {}
+static inline bool track_event_change(struct bch2_time_stats *stats,
+                                     u64 *start, bool v)
+{
+       bool ret = v && !*start;
+       *start = v;
+       return ret;
+}
+#endif
+
+void bch2_time_stats_to_text(struct printbuf *, struct bch2_time_stats *);
+
+void bch2_time_stats_exit(struct bch2_time_stats *);
+void bch2_time_stats_init(struct bch2_time_stats *);
+
+#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;                 \
+})
+
+/* 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);
+int bch2_bio_alloc_pages(struct bio *, size_t, gfp_t);
+
+static inline sector_t bdev_sectors(struct block_device *bdev)
+{
+       return bdev->bd_inode->i_size >> 9;
+}
+
+#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;                                                           \
+})
+
+size_t bch2_rand_range(size_t);
+
+void memcpy_to_bio(struct bio *, struct bvec_iter, const void *);
+void memcpy_from_bio(void *, struct bio *, struct bvec_iter);
+
+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)
+{
+#ifdef CONFIG_X86_64
+       long d0, d1, d2;
+
+       asm volatile("rep ; movsq"
+                    : "=&c" (d0), "=&D" (d1), "=&S" (d2)
+                    : "0" (u64s), "1" (dst), "2" (src)
+                    : "memory");
+#else
+       u64 *d = dst;
+       const u64 *s = src;
+
+       while (u64s--)
+               *d++ = *s++;
+#endif
+}
+
+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 __memmove_u64s_down(void *dst, const void *src,
+                                      unsigned u64s)
+{
+       __memcpy_u64s(dst, src, u64s);
+}
+
+static inline void memmove_u64s_down(void *dst, const void *src,
+                                    unsigned u64s)
+{
+       EBUG_ON(dst > src);
+
+       __memmove_u64s_down(dst, src, u64s);
+}
+
+static inline void __memmove_u64s_down_small(void *dst, const void *src,
+                                      unsigned u64s)
+{
+       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, const void *_src,
+                                    unsigned u64s)
+{
+       u64 *dst = (u64 *) _dst + u64s - 1;
+       u64 *src = (u64 *) _src + u64s - 1;
+
+#ifdef CONFIG_X86_64
+       long d0, d1, d2;
+
+       asm volatile("std ;\n"
+                    "rep ; movsq\n"
+                    "cld ;\n"
+                    : "=&c" (d0), "=&D" (d1), "=&S" (d2)
+                    : "0" (u64s), "1" (dst), "2" (src)
+                    : "memory");
+#else
+       while (u64s--)
+               *dst-- = *src--;
+#endif
+}
+
+static inline void memmove_u64s_up(void *dst, const void *src,
+                                  unsigned u64s)
+{
+       EBUG_ON(dst < src);
+
+       __memmove_u64s_up(dst, src, u64s);
+}
+
+static inline void memmove_u64s(void *dst, const void *src,
+                               unsigned u64s)
+{
+       if (dst < src)
+               __memmove_u64s_down(dst, src, u64s);
+       else
+               __memmove_u64s_up(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)
+{
+       unsigned rem = round_up(bytes, sizeof(u64)) - bytes;
+
+       memset(s + bytes, c, rem);
+}
+
+void sort_cmp_size(void *base, size_t num, size_t size,
+         int (*cmp_func)(const void *, const void *, size_t),
+         void (*swap_func)(void *, void *, size_t));
+
+/* 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(_array, _nr, _size, _old_gap, _new_gap)       \
+       __move_gap(_array, sizeof(_array[0]), _nr, _size, _old_gap, _new_gap)
+
+#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)
+
+static inline u64 percpu_u64_get(u64 __percpu *src)
+{
+       u64 ret = 0;
+       int cpu;
+
+       for_each_possible_cpu(cpu)
+               ret += *per_cpu_ptr(src, cpu);
+       return ret;
+}
+
+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)
+{
+       unsigned i;
+
+       for (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);
+
+#define cmp_int(l, r)          ((l > r) - (l < r))
+
+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>
+
+#define QSTR(n) { { { .len = strlen(n) } }, .name = n }
+
+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);
+}
+
+void bch2_darray_str_exit(darray_str *);
+int bch2_split_devs(const char *, darray_str *);
+
+#endif /* _BCACHEFS_UTIL_H */