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MIPS: signal: Remove FP context support when CONFIG_MIPS_FP_SUPPORT=n 

When CONFIG_MIPS_FP_SUPPORT=n we don't support floating point, so
there's no need to save & restore floating point context around signals.
This prepares us for the removal of FP context from struct task_struct
later.

Since MSA context is a superset of FP context support for it similarly
needs to be removed when MSA/FP support is disabled.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21009/
Cc: linux-mips@linux-mips.org
This commit is contained in:
Paul Burton 2018-11-07 23:14:08 +00:00
parent 6c79759eca
commit 4eec81d7d8
No known key found for this signature in database
GPG Key ID: 3EA79FACB57500DD
1 changed files with 34 additions and 5 deletions
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39
arch/mips/kernel/signal.c
View File

@ -62,6 +62,8 @@ struct rt_sigframe {
struct ucontext rs_uc;
};
#ifdef CONFIG_MIPS_FP_SUPPORT
/*
* Thread saved context copy to/from a signal context presumed to be on the
* user stack, and therefore accessed with appropriate macros from uaccess.h.
@ -104,6 +106,20 @@ static int copy_fp_from_sigcontext(void __user *sc)
return err;
}
#else /* !CONFIG_MIPS_FP_SUPPORT */
static int copy_fp_to_sigcontext(void __user *sc)
{
return 0;
}
static int copy_fp_from_sigcontext(void __user *sc)
{
return 0;
}
#endif /* !CONFIG_MIPS_FP_SUPPORT */
/*
* Wrappers for the assembly _{save,restore}_fp_context functions.
*/
@ -142,6 +158,8 @@ static inline void __user *sc_to_extcontext(void __user *sc)
return &uc->uc_extcontext;
}
#ifdef CONFIG_CPU_HAS_MSA
static int save_msa_extcontext(void __user *buf)
{
struct msa_extcontext __user *msa = buf;
@ -195,9 +213,6 @@ static int restore_msa_extcontext(void __user *buf, unsigned int size)
unsigned int csr;
int i, err;
if (!IS_ENABLED(CONFIG_CPU_HAS_MSA))
return SIGSYS;
if (size != sizeof(*msa))
return -EINVAL;
@ -234,6 +249,20 @@ static int restore_msa_extcontext(void __user *buf, unsigned int size)
return err;
}
#else /* !CONFIG_CPU_HAS_MSA */
static int save_msa_extcontext(void __user *buf)
{
return 0;
}
static int restore_msa_extcontext(void __user *buf, unsigned int size)
{
return SIGSYS;
}
#endif /* !CONFIG_CPU_HAS_MSA */
static int save_extcontext(void __user *buf)
{
int sz;
@ -880,7 +909,7 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
user_enter();
}
#ifdef CONFIG_SMP
#if defined(CONFIG_SMP) && defined(CONFIG_MIPS_FP_SUPPORT)
static int smp_save_fp_context(void __user *sc)
{
return raw_cpu_has_fpu
@ -908,7 +937,7 @@ static int signal_setup(void)
(offsetof(struct rt_sigframe, rs_uc.uc_extcontext) -
offsetof(struct rt_sigframe, rs_uc.uc_mcontext)));
#ifdef CONFIG_SMP
#if defined(CONFIG_SMP) && defined(CONFIG_MIPS_FP_SUPPORT)
/* For now just do the cpu_has_fpu check when the functions are invoked */
save_fp_context = smp_save_fp_context;
restore_fp_context = smp_restore_fp_context;