linux/fs/bcachefs/fifo.h
Kent Overstreet 4077991c85 bcachefs: Fix a use after free in the journal code
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
2023-10-22 17:08:07 -04:00

126 lines
3.5 KiB
C

/* 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) \
(roundup_pow_of_two((fifo)->size) * sizeof((fifo)->data[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 */