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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef _BCACHEFS_FIFO_H3#define _BCACHEFS_FIFO_H4 5#include "util.h"6 7#define FIFO(type) \8struct { \9 size_t front, back, size, mask; \10 type *data; \11}12 13#define DECLARE_FIFO(type, name) FIFO(type) name14 15#define fifo_buf_size(fifo) \16 ((fifo)->size \17 ? roundup_pow_of_two((fifo)->size) * sizeof((fifo)->data[0]) \18 : 0)19 20#define init_fifo(fifo, _size, _gfp) \21({ \22 (fifo)->front = (fifo)->back = 0; \23 (fifo)->size = (_size); \24 (fifo)->mask = (fifo)->size \25 ? roundup_pow_of_two((fifo)->size) - 1 \26 : 0; \27 (fifo)->data = kvmalloc(fifo_buf_size(fifo), (_gfp)); \28})29 30#define free_fifo(fifo) \31do { \32 kvfree((fifo)->data); \33 (fifo)->data = NULL; \34} while (0)35 36#define fifo_swap(l, r) \37do { \38 swap((l)->front, (r)->front); \39 swap((l)->back, (r)->back); \40 swap((l)->size, (r)->size); \41 swap((l)->mask, (r)->mask); \42 swap((l)->data, (r)->data); \43} while (0)44 45#define fifo_move(dest, src) \46do { \47 typeof(*((dest)->data)) _t; \48 while (!fifo_full(dest) && \49 fifo_pop(src, _t)) \50 fifo_push(dest, _t); \51} while (0)52 53#define fifo_used(fifo) (((fifo)->back - (fifo)->front))54#define fifo_free(fifo) ((fifo)->size - fifo_used(fifo))55 56#define fifo_empty(fifo) ((fifo)->front == (fifo)->back)57#define fifo_full(fifo) (fifo_used(fifo) == (fifo)->size)58 59#define fifo_peek_front(fifo) ((fifo)->data[(fifo)->front & (fifo)->mask])60#define fifo_peek_back(fifo) ((fifo)->data[((fifo)->back - 1) & (fifo)->mask])61 62#define fifo_entry_idx_abs(fifo, p) \63 ((((p) >= &fifo_peek_front(fifo) \64 ? (fifo)->front : (fifo)->back) & ~(fifo)->mask) + \65 (((p) - (fifo)->data)))66 67#define fifo_entry_idx(fifo, p) (((p) - &fifo_peek_front(fifo)) & (fifo)->mask)68#define fifo_idx_entry(fifo, i) ((fifo)->data[((fifo)->front + (i)) & (fifo)->mask])69 70#define fifo_push_back_ref(f) \71 (fifo_full((f)) ? NULL : &(f)->data[(f)->back++ & (f)->mask])72 73#define fifo_push_front_ref(f) \74 (fifo_full((f)) ? NULL : &(f)->data[--(f)->front & (f)->mask])75 76#define fifo_push_back(fifo, new) \77({ \78 typeof((fifo)->data) _r = fifo_push_back_ref(fifo); \79 if (_r) \80 *_r = (new); \81 _r != NULL; \82})83 84#define fifo_push_front(fifo, new) \85({ \86 typeof((fifo)->data) _r = fifo_push_front_ref(fifo); \87 if (_r) \88 *_r = (new); \89 _r != NULL; \90})91 92#define fifo_pop_front(fifo, i) \93({ \94 bool _r = !fifo_empty((fifo)); \95 if (_r) \96 (i) = (fifo)->data[(fifo)->front++ & (fifo)->mask]; \97 _r; \98})99 100#define fifo_pop_back(fifo, i) \101({ \102 bool _r = !fifo_empty((fifo)); \103 if (_r) \104 (i) = (fifo)->data[--(fifo)->back & (fifo)->mask]; \105 _r; \106})107 108#define fifo_push_ref(fifo) fifo_push_back_ref(fifo)109#define fifo_push(fifo, i) fifo_push_back(fifo, (i))110#define fifo_pop(fifo, i) fifo_pop_front(fifo, (i))111#define fifo_peek(fifo) fifo_peek_front(fifo)112 113#define fifo_for_each_entry(_entry, _fifo, _iter) \114 for (typecheck(typeof((_fifo)->front), _iter), \115 (_iter) = (_fifo)->front; \116 ((_iter != (_fifo)->back) && \117 (_entry = (_fifo)->data[(_iter) & (_fifo)->mask], true)); \118 (_iter)++)119 120#define fifo_for_each_entry_ptr(_ptr, _fifo, _iter) \121 for (typecheck(typeof((_fifo)->front), _iter), \122 (_iter) = (_fifo)->front; \123 ((_iter != (_fifo)->back) && \124 (_ptr = &(_fifo)->data[(_iter) & (_fifo)->mask], true)); \125 (_iter)++)126 127#endif /* _BCACHEFS_FIFO_H */128