xref: /freebsd/sys/contrib/openzfs/config/kernel-fpu.m4 (revision 8b959dd6a3921c35395bef4a6d7ad2426a3bd88e)
1dnl #
2dnl # Handle differences in kernel FPU code.
3dnl #
4dnl # Kernel
5dnl # 5.0:	Wrappers have been introduced to save/restore the FPU state.
6dnl #		This change was made to the 4.19.38 and 4.14.120 LTS kernels.
7dnl #		HAVE_KERNEL_FPU_INTERNAL
8dnl #
9dnl # 4.2:	Use __kernel_fpu_{begin,end}()
10dnl #		HAVE_UNDERSCORE_KERNEL_FPU & KERNEL_EXPORTS_X86_FPU
11dnl #
12dnl # Pre-4.2:	Use kernel_fpu_{begin,end}()
13dnl #		HAVE_KERNEL_FPU & KERNEL_EXPORTS_X86_FPU
14dnl #
15dnl # N.B. The header check is performed before all other checks since it
16dnl # depends on HAVE_KERNEL_FPU_API_HEADER being set in confdefs.h.
17dnl #
18AC_DEFUN([ZFS_AC_KERNEL_FPU_HEADER], [
19	AC_MSG_CHECKING([whether fpu headers are available])
20	ZFS_LINUX_TRY_COMPILE([
21		#include <linux/module.h>
22		#include <asm/fpu/api.h>
23	],[
24	],[
25		AC_DEFINE(HAVE_KERNEL_FPU_API_HEADER, 1,
26		    [kernel has asm/fpu/api.h])
27		AC_MSG_RESULT(asm/fpu/api.h)
28	],[
29		AC_MSG_RESULT(i387.h & xcr.h)
30	])
31])
32
33AC_DEFUN([ZFS_AC_KERNEL_SRC_FPU], [
34	ZFS_LINUX_TEST_SRC([kernel_fpu], [
35		#include <linux/types.h>
36		#ifdef HAVE_KERNEL_FPU_API_HEADER
37		#include <asm/fpu/api.h>
38		#else
39		#include <asm/i387.h>
40		#include <asm/xcr.h>
41		#endif
42	], [
43		kernel_fpu_begin();
44		kernel_fpu_end();
45	], [], [ZFS_META_LICENSE])
46
47	ZFS_LINUX_TEST_SRC([__kernel_fpu], [
48		#include <linux/types.h>
49		#ifdef HAVE_KERNEL_FPU_API_HEADER
50		#include <asm/fpu/api.h>
51		#else
52		#include <asm/i387.h>
53		#include <asm/xcr.h>
54		#endif
55	], [
56		__kernel_fpu_begin();
57		__kernel_fpu_end();
58	], [], [ZFS_META_LICENSE])
59
60	ZFS_LINUX_TEST_SRC([fpu_internal], [
61		#if defined(__x86_64) || defined(__x86_64__) || \
62		    defined(__i386) || defined(__i386__)
63		#if !defined(__x86)
64		#define __x86
65		#endif
66		#endif
67
68		#if !defined(__x86)
69		#error Unsupported architecture
70		#endif
71
72		#include <linux/types.h>
73		#ifdef HAVE_KERNEL_FPU_API_HEADER
74		#include <asm/fpu/api.h>
75		#include <asm/fpu/internal.h>
76		#else
77		#include <asm/i387.h>
78		#include <asm/xcr.h>
79		#endif
80
81		#if !defined(XSTATE_XSAVE)
82		#error XSTATE_XSAVE not defined
83		#endif
84
85		#if !defined(XSTATE_XRESTORE)
86		#error XSTATE_XRESTORE not defined
87		#endif
88	],[
89		struct fpu *fpu = &current->thread.fpu;
90		union fpregs_state *st = &fpu->state;
91		struct fregs_state *fr __attribute__ ((unused)) = &st->fsave;
92		struct fxregs_state *fxr __attribute__ ((unused)) = &st->fxsave;
93		struct xregs_state *xr __attribute__ ((unused)) = &st->xsave;
94	])
95])
96
97AC_DEFUN([ZFS_AC_KERNEL_FPU], [
98	dnl #
99	dnl # Legacy kernel
100	dnl #
101	AC_MSG_CHECKING([whether kernel fpu is available])
102	ZFS_LINUX_TEST_RESULT_SYMBOL([kernel_fpu_license],
103	    [kernel_fpu_begin], [arch/x86/kernel/fpu/core.c], [
104		AC_MSG_RESULT(kernel_fpu_*)
105		AC_DEFINE(HAVE_KERNEL_FPU, 1,
106		    [kernel has kernel_fpu_* functions])
107		AC_DEFINE(KERNEL_EXPORTS_X86_FPU, 1,
108		    [kernel exports FPU functions])
109	],[
110		dnl #
111		dnl # Linux 4.2 kernel
112		dnl #
113		ZFS_LINUX_TEST_RESULT_SYMBOL([__kernel_fpu_license],
114		    [__kernel_fpu_begin],
115		    [arch/x86/kernel/fpu/core.c arch/x86/kernel/i387.c], [
116			AC_MSG_RESULT(__kernel_fpu_*)
117			AC_DEFINE(HAVE_UNDERSCORE_KERNEL_FPU, 1,
118			    [kernel has __kernel_fpu_* functions])
119			AC_DEFINE(KERNEL_EXPORTS_X86_FPU, 1,
120			    [kernel exports FPU functions])
121		],[
122			ZFS_LINUX_TEST_RESULT([fpu_internal], [
123				AC_MSG_RESULT(internal)
124				AC_DEFINE(HAVE_KERNEL_FPU_INTERNAL, 1,
125				    [kernel fpu internal])
126			],[
127				AC_MSG_RESULT(unavailable)
128			])
129		])
130	])
131])
132