Files
RedBear-OS/recipes/tools/nano/source/lib/xsize.h
T
vasilito 7686729069 drm: implement syncobj and fence for VIRGL/VirtIO driver
Extract protocol-agnostic FenceTimeline from Intel to shared
src/drivers/fence.rs — atomic-based fence tracking suitable
for Intel, VIRGL, and AMD drivers.

Extract protocol-agnostic SyncobjManager from Intel to shared
src/drivers/syncobj.rs — syncobj create/destroy/signal/reset/
wait/query and sync_file fd export/import.

Wire both into VirtioDriver:
- Add FenceTimeline + SyncobjManager fields
- Implement all 5 GpuDriver syncobj trait methods
  (create, destroy, wait, export_fd, import_fd)
- Track fence seqnos in virgl_submit_3d (allocate
  before submit, signal after completion)

Intel fence.rs and syncobj.rs converted to thin re-export
modules pointing at shared sources — no behavioral change
for Intel driver.

This gives Mesa VIRGL userspace the standard DRM syncobj
API for GPU/compositor synchronization.
2026-06-02 14:33:28 +03:00

109 lines
3.5 KiB
C

/* xsize.h -- Checked size_t computations.
Copyright (C) 2003, 2008-2023 Free Software Foundation, Inc.
This file is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2.1 of the
License, or (at your option) any later version.
This file is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>. */
#ifndef _XSIZE_H
#define _XSIZE_H
/* Get size_t. */
#include <stddef.h>
/* Get SIZE_MAX. */
#include <limits.h>
#if HAVE_STDINT_H
# include <stdint.h>
#endif
/* Get ATTRIBUTE_PURE. */
#include "attribute.h"
#ifndef _GL_INLINE_HEADER_BEGIN
#error "Please include config.h first."
#endif
_GL_INLINE_HEADER_BEGIN
#ifndef XSIZE_INLINE
# define XSIZE_INLINE _GL_INLINE
#endif
/* The size of memory objects is often computed through expressions of
type size_t. Example:
void* p = malloc (header_size + n * element_size).
These computations can lead to overflow. When this happens, malloc()
returns a piece of memory that is way too small, and the program then
crashes while attempting to fill the memory.
To avoid this, the functions and macros in this file check for overflow.
The convention is that SIZE_MAX represents overflow.
malloc (SIZE_MAX) is not guaranteed to fail -- think of a malloc
implementation that uses mmap --, it's recommended to use size_overflow_p()
or size_in_bounds_p() before invoking malloc().
The example thus becomes:
size_t size = xsum (header_size, xtimes (n, element_size));
void *p = (size_in_bounds_p (size) ? malloc (size) : NULL);
*/
/* Convert an arbitrary value >= 0 to type size_t. */
#define xcast_size_t(N) \
((N) <= SIZE_MAX ? (size_t) (N) : SIZE_MAX)
/* Sum of two sizes, with overflow check. */
XSIZE_INLINE size_t ATTRIBUTE_PURE
xsum (size_t size1, size_t size2)
{
size_t sum = size1 + size2;
return (sum >= size1 ? sum : SIZE_MAX);
}
/* Sum of three sizes, with overflow check. */
XSIZE_INLINE size_t ATTRIBUTE_PURE
xsum3 (size_t size1, size_t size2, size_t size3)
{
return xsum (xsum (size1, size2), size3);
}
/* Sum of four sizes, with overflow check. */
XSIZE_INLINE size_t ATTRIBUTE_PURE
xsum4 (size_t size1, size_t size2, size_t size3, size_t size4)
{
return xsum (xsum (xsum (size1, size2), size3), size4);
}
/* Maximum of two sizes, with overflow check. */
XSIZE_INLINE size_t ATTRIBUTE_PURE
xmax (size_t size1, size_t size2)
{
/* No explicit check is needed here, because for any n:
max (SIZE_MAX, n) == SIZE_MAX and max (n, SIZE_MAX) == SIZE_MAX. */
return (size1 >= size2 ? size1 : size2);
}
/* Multiplication of a count with an element size, with overflow check.
The count must be >= 0 and the element size must be > 0.
This is a macro, not a function, so that it works correctly even
when N is of a wider type and N > SIZE_MAX. */
#define xtimes(N, ELSIZE) \
((N) <= SIZE_MAX / (ELSIZE) ? (size_t) (N) * (ELSIZE) : SIZE_MAX)
/* Check for overflow. */
#define size_overflow_p(SIZE) \
((SIZE) == SIZE_MAX)
/* Check against overflow. */
#define size_in_bounds_p(SIZE) \
((SIZE) != SIZE_MAX)
_GL_INLINE_HEADER_END
#endif /* _XSIZE_H */