xref: /linux/arch/loongarch/include/uapi/asm/ucontext.h (revision 4f2c0a4acffbec01079c28f839422e64ddeff004)
1*b74baf4aSHuacai Chen /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2*b74baf4aSHuacai Chen #ifndef __LOONGARCH_UAPI_ASM_UCONTEXT_H
3*b74baf4aSHuacai Chen #define __LOONGARCH_UAPI_ASM_UCONTEXT_H
4*b74baf4aSHuacai Chen 
5*b74baf4aSHuacai Chen /**
6*b74baf4aSHuacai Chen  * struct ucontext - user context structure
7*b74baf4aSHuacai Chen  * @uc_flags:
8*b74baf4aSHuacai Chen  * @uc_link:
9*b74baf4aSHuacai Chen  * @uc_stack:
10*b74baf4aSHuacai Chen  * @uc_mcontext:	holds basic processor state
11*b74baf4aSHuacai Chen  * @uc_sigmask:
12*b74baf4aSHuacai Chen  * @uc_extcontext:	holds extended processor state
13*b74baf4aSHuacai Chen  */
14*b74baf4aSHuacai Chen struct ucontext {
15*b74baf4aSHuacai Chen 	unsigned long		uc_flags;
16*b74baf4aSHuacai Chen 	struct ucontext		*uc_link;
17*b74baf4aSHuacai Chen 	stack_t			uc_stack;
18*b74baf4aSHuacai Chen 	sigset_t		uc_sigmask;
19*b74baf4aSHuacai Chen 	/* There's some padding here to allow sigset_t to be expanded in the
20*b74baf4aSHuacai Chen 	 * future.  Though this is unlikely, other architectures put uc_sigmask
21*b74baf4aSHuacai Chen 	 * at the end of this structure and explicitly state it can be
22*b74baf4aSHuacai Chen 	 * expanded, so we didn't want to box ourselves in here. */
23*b74baf4aSHuacai Chen 	__u8		  __unused[1024 / 8 - sizeof(sigset_t)];
24*b74baf4aSHuacai Chen 	/* We can't put uc_sigmask at the end of this structure because we need
25*b74baf4aSHuacai Chen 	 * to be able to expand sigcontext in the future.  For example, the
26*b74baf4aSHuacai Chen 	 * vector ISA extension will almost certainly add ISA state.  We want
27*b74baf4aSHuacai Chen 	 * to ensure all user-visible ISA state can be saved and restored via a
28*b74baf4aSHuacai Chen 	 * ucontext, so we're putting this at the end in order to allow for
29*b74baf4aSHuacai Chen 	 * infinite extensibility.  Since we know this will be extended and we
30*b74baf4aSHuacai Chen 	 * assume sigset_t won't be extended an extreme amount, we're
31*b74baf4aSHuacai Chen 	 * prioritizing this. */
32*b74baf4aSHuacai Chen 	struct sigcontext	uc_mcontext;
33*b74baf4aSHuacai Chen };
34*b74baf4aSHuacai Chen 
35*b74baf4aSHuacai Chen #endif /* __LOONGARCH_UAPI_ASM_UCONTEXT_H */
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