move Rust sources to top level, C sources into c_src

[bcachefs-tools-debian] / c_src / libbcachefs / fifo.h

diff --git a/c_src/libbcachefs/fifo.h b/c_src/libbcachefs/fifo.h
new file mode 100644 (file)
index 0000000..66b945b
--- /dev/null
+++ b/c_src/libbcachefs/fifo.h
@@ -0,0 +1,127 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _BCACHEFS_FIFO_H
+#define _BCACHEFS_FIFO_H
+
+#include "util.h"
+
+#define FIFO(type)                                                     \
+struct {                                                               \
+       size_t front, back, size, mask;                                 \
+       type *data;                                                     \
+}
+
+#define DECLARE_FIFO(type, name)       FIFO(type) name
+
+#define fifo_buf_size(fifo)                                            \
+       ((fifo)->size                                                   \
+        ? roundup_pow_of_two((fifo)->size) * sizeof((fifo)->data[0])   \
+        : 0)
+
+#define init_fifo(fifo, _size, _gfp)                                   \
+({                                                                     \
+       (fifo)->front   = (fifo)->back = 0;                             \
+       (fifo)->size    = (_size);                                      \
+       (fifo)->mask    = (fifo)->size                                  \
+               ? roundup_pow_of_two((fifo)->size) - 1                  \
+               : 0;                                                    \
+       (fifo)->data    = kvpmalloc(fifo_buf_size(fifo), (_gfp));       \
+})
+
+#define free_fifo(fifo)                                                        \
+do {                                                                   \
+       kvpfree((fifo)->data, fifo_buf_size(fifo));                     \
+       (fifo)->data = NULL;                                            \
+} while (0)
+
+#define fifo_swap(l, r)                                                        \
+do {                                                                   \
+       swap((l)->front, (r)->front);                                   \
+       swap((l)->back, (r)->back);                                     \
+       swap((l)->size, (r)->size);                                     \
+       swap((l)->mask, (r)->mask);                                     \
+       swap((l)->data, (r)->data);                                     \
+} while (0)
+
+#define fifo_move(dest, src)                                           \
+do {                                                                   \
+       typeof(*((dest)->data)) _t;                                     \
+       while (!fifo_full(dest) &&                                      \
+              fifo_pop(src, _t))                                       \
+               fifo_push(dest, _t);                                    \
+} while (0)
+
+#define fifo_used(fifo)                (((fifo)->back - (fifo)->front))
+#define fifo_free(fifo)                ((fifo)->size - fifo_used(fifo))
+
+#define fifo_empty(fifo)       ((fifo)->front == (fifo)->back)
+#define fifo_full(fifo)                (fifo_used(fifo) == (fifo)->size)
+
+#define fifo_peek_front(fifo)  ((fifo)->data[(fifo)->front & (fifo)->mask])
+#define fifo_peek_back(fifo)   ((fifo)->data[((fifo)->back - 1) & (fifo)->mask])
+
+#define fifo_entry_idx_abs(fifo, p)                                    \
+       ((((p) >= &fifo_peek_front(fifo)                                \
+          ? (fifo)->front : (fifo)->back) & ~(fifo)->mask) +           \
+          (((p) - (fifo)->data)))
+
+#define fifo_entry_idx(fifo, p)        (((p) - &fifo_peek_front(fifo)) & (fifo)->mask)
+#define fifo_idx_entry(fifo, i)        ((fifo)->data[((fifo)->front + (i)) & (fifo)->mask])
+
+#define fifo_push_back_ref(f)                                          \
+       (fifo_full((f)) ? NULL : &(f)->data[(f)->back++ & (f)->mask])
+
+#define fifo_push_front_ref(f)                                         \
+       (fifo_full((f)) ? NULL : &(f)->data[--(f)->front & (f)->mask])
+
+#define fifo_push_back(fifo, new)                                      \
+({                                                                     \
+       typeof((fifo)->data) _r = fifo_push_back_ref(fifo);             \
+       if (_r)                                                         \
+               *_r = (new);                                            \
+       _r != NULL;                                                     \
+})
+
+#define fifo_push_front(fifo, new)                                     \
+({                                                                     \
+       typeof((fifo)->data) _r = fifo_push_front_ref(fifo);            \
+       if (_r)                                                         \
+               *_r = (new);                                            \
+       _r != NULL;                                                     \
+})
+
+#define fifo_pop_front(fifo, i)                                                \
+({                                                                     \
+       bool _r = !fifo_empty((fifo));                                  \
+       if (_r)                                                         \
+               (i) = (fifo)->data[(fifo)->front++ & (fifo)->mask];     \
+       _r;                                                             \
+})
+
+#define fifo_pop_back(fifo, i)                                         \
+({                                                                     \
+       bool _r = !fifo_empty((fifo));                                  \
+       if (_r)                                                         \
+               (i) = (fifo)->data[--(fifo)->back & (fifo)->mask];      \
+       _r;                                                             \
+})
+
+#define fifo_push_ref(fifo)    fifo_push_back_ref(fifo)
+#define fifo_push(fifo, i)     fifo_push_back(fifo, (i))
+#define fifo_pop(fifo, i)      fifo_pop_front(fifo, (i))
+#define fifo_peek(fifo)                fifo_peek_front(fifo)
+
+#define fifo_for_each_entry(_entry, _fifo, _iter)                      \
+       for (typecheck(typeof((_fifo)->front), _iter),                  \
+            (_iter) = (_fifo)->front;                                  \
+            ((_iter != (_fifo)->back) &&                               \
+             (_entry = (_fifo)->data[(_iter) & (_fifo)->mask], true)); \
+            (_iter)++)
+
+#define fifo_for_each_entry_ptr(_ptr, _fifo, _iter)                    \
+       for (typecheck(typeof((_fifo)->front), _iter),                  \
+            (_iter) = (_fifo)->front;                                  \
+            ((_iter != (_fifo)->back) &&                               \
+             (_ptr = &(_fifo)->data[(_iter) & (_fifo)->mask], true));  \
+            (_iter)++)
+
+#endif /* _BCACHEFS_FIFO_H */