LXR linux/arch/arm/include/asm/ucontext.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _ASMARM_UCONTEXT_H
   3#define _ASMARM_UCONTEXT_H
   4
   5#include <asm/fpstate.h>
   6#include <asm/user.h>
   7
   8/*
   9 * struct sigcontext only has room for the basic registers, but struct
  10 * ucontext now has room for all registers which need to be saved and
  11 * restored.  Coprocessor registers are stored in uc_regspace.  Each
  12 * coprocessor's saved state should start with a documented 32-bit magic
  13 * number, followed by a 32-bit word giving the coproccesor's saved size.
  14 * uc_regspace may be expanded if necessary, although this takes some
  15 * coordination with glibc.
  16 */
  17
  18struct ucontext {
  19        unsigned long     uc_flags;
  20        struct ucontext  *uc_link;
  21        stack_t           uc_stack;
  22        struct sigcontext uc_mcontext;
  23        sigset_t          uc_sigmask;
  24        /* Allow for uc_sigmask growth.  Glibc uses a 1024-bit sigset_t.  */
  25        int               __unused[32 - (sizeof (sigset_t) / sizeof (int))];
  26        /* Last for extensibility.  Eight byte aligned because some
  27           coprocessors require eight byte alignment.  */
  28        unsigned long     uc_regspace[128] __attribute__((__aligned__(8)));
  29};
  30
  31#ifdef __KERNEL__
  32
  33/*
  34 * Coprocessor save state.  The magic values and specific
  35 * coprocessor's layouts are part of the userspace ABI.  Each one of
  36 * these should be a multiple of eight bytes and aligned to eight
  37 * bytes, to prevent unpredictable padding in the signal frame.
  38 */
  39
  40/*
  41 * Dummy padding block: if this magic is encountered, the block should
  42 * be skipped using the corresponding size field.
  43 */
  44#define DUMMY_MAGIC             0xb0d9ed01
  45
  46#ifdef CONFIG_IWMMXT
  47/* iwmmxt_area is 0x98 bytes long, preceded by 8 bytes of signature */
  48#define IWMMXT_MAGIC            0x12ef842a
  49#define IWMMXT_STORAGE_SIZE     (IWMMXT_SIZE + 8)
  50
  51struct iwmmxt_sigframe {
  52        unsigned long   magic;
  53        unsigned long   size;
  54        struct iwmmxt_struct storage;
  55} __attribute__((__aligned__(8)));
  56#endif /* CONFIG_IWMMXT */
  57
  58#ifdef CONFIG_VFP
  59#define VFP_MAGIC               0x56465001
  60
  61struct vfp_sigframe
  62{
  63        unsigned long           magic;
  64        unsigned long           size;
  65        struct user_vfp         ufp;
  66        struct user_vfp_exc     ufp_exc;
  67} __attribute__((__aligned__(8)));
  68
  69/*
  70 *  8 byte for magic and size, 264 byte for ufp, 12 bytes for ufp_exc,
  71 *  4 bytes padding.
  72 */
  73#define VFP_STORAGE_SIZE        sizeof(struct vfp_sigframe)
  74
  75#endif /* CONFIG_VFP */
  76
  77/*
  78 * Auxiliary signal frame.  This saves stuff like FP state.
  79 * The layout of this structure is not part of the user ABI,
  80 * because the config options aren't.  uc_regspace is really
  81 * one of these.
  82 */
  83struct aux_sigframe {
  84#ifdef CONFIG_IWMMXT
  85        struct iwmmxt_sigframe  iwmmxt;
  86#endif
  87#ifdef CONFIG_VFP
  88        struct vfp_sigframe     vfp;
  89#endif
  90        /* Something that isn't a valid magic number for any coprocessor.  */
  91        unsigned long           end_magic;
  92} __attribute__((__aligned__(8)));
  93
  94#endif
  95
  96#endif /* !_ASMARM_UCONTEXT_H */
  97