[2.1] compat: add check for kernel_neon_* availability

This patch backports the change from #15711 (to ZFS 2.2.x) because
some OS vendors have back-ported this change from Linux 6.2+ to their
older kernels.

The original patch addressed these issues:

1. Linux 6.2+ on arm64 has exported them with `EXPORT_SYMBOL_GPL`, so
   license compatibility must be checked before use.
2. On both arm and arm64, the definitions of these symbols are guarded
   by `CONFIG_KERNEL_MODE_NEON`, but their declarations are still
   present. Checking in configuration phase only leads to MODPOST
   errors (undefined references).

Signed-off-by: Keith Gable <keith@ziggythehamster.sh>
Co-authored-by: Shengqi Chen <harry-chen@outlook.com>
This commit is contained in:
Keith Gable
2024-01-11 15:48:00 -08:00
committed by Brian Behlendorf
parent 12a031a3f5
commit f8f3cac084
2 changed files with 34 additions and 11 deletions
@@ -43,9 +43,15 @@
#include <sys/types.h>
#include <asm/neon.h>
#if (defined(HAVE_KERNEL_NEON) && defined(CONFIG_KERNEL_MODE_NEON))
#define kfpu_allowed() 1
#define kfpu_begin() kernel_neon_begin()
#define kfpu_end() kernel_neon_end()
#else
#define kfpu_allowed() 0
#define kfpu_begin() do {} while (0)
#define kfpu_end() do {} while (0)
#endif
#define kfpu_init() 0
#define kfpu_fini() ((void) 0)