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960 lines
23 KiB
960 lines
23 KiB
/* |
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* This file is subject to the terms and conditions of the GNU General Public |
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* License. See the file "COPYING" in the main directory of this archive |
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* for more details. |
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* |
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* Copyright (C) 1991, 1992 Linus Torvalds |
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* Copyright (C) 1994 - 2000 Ralf Baechle |
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* Copyright (C) 1999, 2000 Silicon Graphics, Inc. |
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* Copyright (C) 2014, Imagination Technologies Ltd. |
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*/ |
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#include <linux/cache.h> |
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#include <linux/context_tracking.h> |
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#include <linux/irqflags.h> |
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#include <linux/sched.h> |
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#include <linux/mm.h> |
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#include <linux/personality.h> |
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#include <linux/smp.h> |
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#include <linux/kernel.h> |
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#include <linux/signal.h> |
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#include <linux/errno.h> |
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#include <linux/wait.h> |
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#include <linux/ptrace.h> |
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#include <linux/unistd.h> |
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#include <linux/uprobes.h> |
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#include <linux/compiler.h> |
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#include <linux/syscalls.h> |
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#include <linux/uaccess.h> |
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#include <linux/tracehook.h> |
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#include <asm/abi.h> |
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#include <asm/asm.h> |
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#include <linux/bitops.h> |
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#include <asm/cacheflush.h> |
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#include <asm/fpu.h> |
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#include <asm/sim.h> |
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#include <asm/ucontext.h> |
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#include <asm/cpu-features.h> |
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#include <asm/war.h> |
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#include <asm/dsp.h> |
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#include <asm/inst.h> |
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#include <asm/msa.h> |
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#include "signal-common.h" |
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static int (*save_fp_context)(void __user *sc); |
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static int (*restore_fp_context)(void __user *sc); |
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struct sigframe { |
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u32 sf_ass[4]; /* argument save space for o32 */ |
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u32 sf_pad[2]; /* Was: signal trampoline */ |
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/* Matches struct ucontext from its uc_mcontext field onwards */ |
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struct sigcontext sf_sc; |
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sigset_t sf_mask; |
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unsigned long long sf_extcontext[]; |
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}; |
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struct rt_sigframe { |
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u32 rs_ass[4]; /* argument save space for o32 */ |
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u32 rs_pad[2]; /* Was: signal trampoline */ |
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struct siginfo rs_info; |
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struct ucontext rs_uc; |
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}; |
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#ifdef CONFIG_MIPS_FP_SUPPORT |
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/* |
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* Thread saved context copy to/from a signal context presumed to be on the |
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* user stack, and therefore accessed with appropriate macros from uaccess.h. |
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*/ |
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static int copy_fp_to_sigcontext(void __user *sc) |
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{ |
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struct mips_abi *abi = current->thread.abi; |
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uint64_t __user *fpregs = sc + abi->off_sc_fpregs; |
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uint32_t __user *csr = sc + abi->off_sc_fpc_csr; |
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int i; |
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int err = 0; |
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int inc = test_thread_flag(TIF_32BIT_FPREGS) ? 2 : 1; |
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for (i = 0; i < NUM_FPU_REGS; i += inc) { |
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err |= |
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__put_user(get_fpr64(¤t->thread.fpu.fpr[i], 0), |
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&fpregs[i]); |
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} |
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err |= __put_user(current->thread.fpu.fcr31, csr); |
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return err; |
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} |
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static int copy_fp_from_sigcontext(void __user *sc) |
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{ |
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struct mips_abi *abi = current->thread.abi; |
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uint64_t __user *fpregs = sc + abi->off_sc_fpregs; |
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uint32_t __user *csr = sc + abi->off_sc_fpc_csr; |
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int i; |
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int err = 0; |
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int inc = test_thread_flag(TIF_32BIT_FPREGS) ? 2 : 1; |
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u64 fpr_val; |
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for (i = 0; i < NUM_FPU_REGS; i += inc) { |
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err |= __get_user(fpr_val, &fpregs[i]); |
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set_fpr64(¤t->thread.fpu.fpr[i], 0, fpr_val); |
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} |
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err |= __get_user(current->thread.fpu.fcr31, csr); |
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return err; |
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} |
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#else /* !CONFIG_MIPS_FP_SUPPORT */ |
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static int copy_fp_to_sigcontext(void __user *sc) |
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{ |
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return 0; |
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} |
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static int copy_fp_from_sigcontext(void __user *sc) |
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{ |
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return 0; |
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} |
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#endif /* !CONFIG_MIPS_FP_SUPPORT */ |
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/* |
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* Wrappers for the assembly _{save,restore}_fp_context functions. |
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*/ |
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static int save_hw_fp_context(void __user *sc) |
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{ |
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struct mips_abi *abi = current->thread.abi; |
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uint64_t __user *fpregs = sc + abi->off_sc_fpregs; |
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uint32_t __user *csr = sc + abi->off_sc_fpc_csr; |
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return _save_fp_context(fpregs, csr); |
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} |
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static int restore_hw_fp_context(void __user *sc) |
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{ |
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struct mips_abi *abi = current->thread.abi; |
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uint64_t __user *fpregs = sc + abi->off_sc_fpregs; |
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uint32_t __user *csr = sc + abi->off_sc_fpc_csr; |
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return _restore_fp_context(fpregs, csr); |
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} |
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/* |
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* Extended context handling. |
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*/ |
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static inline void __user *sc_to_extcontext(void __user *sc) |
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{ |
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struct ucontext __user *uc; |
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/* |
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* We can just pretend the sigcontext is always embedded in a struct |
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* ucontext here, because the offset from sigcontext to extended |
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* context is the same in the struct sigframe case. |
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*/ |
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uc = container_of(sc, struct ucontext, uc_mcontext); |
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return &uc->uc_extcontext; |
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} |
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#ifdef CONFIG_CPU_HAS_MSA |
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static int save_msa_extcontext(void __user *buf) |
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{ |
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struct msa_extcontext __user *msa = buf; |
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uint64_t val; |
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int i, err; |
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if (!thread_msa_context_live()) |
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return 0; |
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/* |
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* Ensure that we can't lose the live MSA context between checking |
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* for it & writing it to memory. |
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*/ |
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preempt_disable(); |
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if (is_msa_enabled()) { |
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/* |
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* There are no EVA versions of the vector register load/store |
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* instructions, so MSA context has to be saved to kernel memory |
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* and then copied to user memory. The save to kernel memory |
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* should already have been done when handling scalar FP |
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* context. |
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*/ |
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BUG_ON(IS_ENABLED(CONFIG_EVA)); |
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err = __put_user(read_msa_csr(), &msa->csr); |
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err |= _save_msa_all_upper(&msa->wr); |
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preempt_enable(); |
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} else { |
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preempt_enable(); |
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err = __put_user(current->thread.fpu.msacsr, &msa->csr); |
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for (i = 0; i < NUM_FPU_REGS; i++) { |
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val = get_fpr64(¤t->thread.fpu.fpr[i], 1); |
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err |= __put_user(val, &msa->wr[i]); |
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} |
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} |
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err |= __put_user(MSA_EXTCONTEXT_MAGIC, &msa->ext.magic); |
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err |= __put_user(sizeof(*msa), &msa->ext.size); |
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return err ? -EFAULT : sizeof(*msa); |
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} |
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static int restore_msa_extcontext(void __user *buf, unsigned int size) |
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{ |
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struct msa_extcontext __user *msa = buf; |
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unsigned long long val; |
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unsigned int csr; |
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int i, err; |
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if (size != sizeof(*msa)) |
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return -EINVAL; |
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err = get_user(csr, &msa->csr); |
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if (err) |
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return err; |
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preempt_disable(); |
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if (is_msa_enabled()) { |
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/* |
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* There are no EVA versions of the vector register load/store |
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* instructions, so MSA context has to be copied to kernel |
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* memory and later loaded to registers. The same is true of |
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* scalar FP context, so FPU & MSA should have already been |
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* disabled whilst handling scalar FP context. |
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*/ |
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BUG_ON(IS_ENABLED(CONFIG_EVA)); |
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write_msa_csr(csr); |
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err |= _restore_msa_all_upper(&msa->wr); |
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preempt_enable(); |
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} else { |
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preempt_enable(); |
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current->thread.fpu.msacsr = csr; |
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for (i = 0; i < NUM_FPU_REGS; i++) { |
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err |= __get_user(val, &msa->wr[i]); |
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set_fpr64(¤t->thread.fpu.fpr[i], 1, val); |
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} |
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} |
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return err; |
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} |
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#else /* !CONFIG_CPU_HAS_MSA */ |
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static int save_msa_extcontext(void __user *buf) |
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{ |
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return 0; |
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} |
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static int restore_msa_extcontext(void __user *buf, unsigned int size) |
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{ |
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return SIGSYS; |
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} |
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#endif /* !CONFIG_CPU_HAS_MSA */ |
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static int save_extcontext(void __user *buf) |
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{ |
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int sz; |
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sz = save_msa_extcontext(buf); |
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if (sz < 0) |
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return sz; |
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buf += sz; |
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/* If no context was saved then trivially return */ |
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if (!sz) |
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return 0; |
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/* Write the end marker */ |
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if (__put_user(END_EXTCONTEXT_MAGIC, (u32 *)buf)) |
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return -EFAULT; |
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sz += sizeof(((struct extcontext *)NULL)->magic); |
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return sz; |
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} |
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static int restore_extcontext(void __user *buf) |
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{ |
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struct extcontext ext; |
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int err; |
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while (1) { |
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err = __get_user(ext.magic, (unsigned int *)buf); |
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if (err) |
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return err; |
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if (ext.magic == END_EXTCONTEXT_MAGIC) |
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return 0; |
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err = __get_user(ext.size, (unsigned int *)(buf |
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+ offsetof(struct extcontext, size))); |
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if (err) |
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return err; |
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switch (ext.magic) { |
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case MSA_EXTCONTEXT_MAGIC: |
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err = restore_msa_extcontext(buf, ext.size); |
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break; |
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default: |
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err = -EINVAL; |
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break; |
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} |
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if (err) |
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return err; |
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buf += ext.size; |
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} |
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} |
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/* |
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* Helper routines |
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*/ |
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int protected_save_fp_context(void __user *sc) |
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{ |
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struct mips_abi *abi = current->thread.abi; |
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uint64_t __user *fpregs = sc + abi->off_sc_fpregs; |
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uint32_t __user *csr = sc + abi->off_sc_fpc_csr; |
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uint32_t __user *used_math = sc + abi->off_sc_used_math; |
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unsigned int used, ext_sz; |
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int err; |
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used = used_math() ? USED_FP : 0; |
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if (!used) |
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goto fp_done; |
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if (!test_thread_flag(TIF_32BIT_FPREGS)) |
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used |= USED_FR1; |
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if (test_thread_flag(TIF_HYBRID_FPREGS)) |
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used |= USED_HYBRID_FPRS; |
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/* |
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* EVA does not have userland equivalents of ldc1 or sdc1, so |
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* save to the kernel FP context & copy that to userland below. |
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*/ |
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if (IS_ENABLED(CONFIG_EVA)) |
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lose_fpu(1); |
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while (1) { |
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lock_fpu_owner(); |
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if (is_fpu_owner()) { |
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err = save_fp_context(sc); |
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unlock_fpu_owner(); |
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} else { |
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unlock_fpu_owner(); |
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err = copy_fp_to_sigcontext(sc); |
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} |
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if (likely(!err)) |
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break; |
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/* touch the sigcontext and try again */ |
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err = __put_user(0, &fpregs[0]) | |
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__put_user(0, &fpregs[31]) | |
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__put_user(0, csr); |
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if (err) |
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return err; /* really bad sigcontext */ |
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} |
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fp_done: |
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ext_sz = err = save_extcontext(sc_to_extcontext(sc)); |
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if (err < 0) |
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return err; |
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used |= ext_sz ? USED_EXTCONTEXT : 0; |
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return __put_user(used, used_math); |
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} |
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int protected_restore_fp_context(void __user *sc) |
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{ |
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struct mips_abi *abi = current->thread.abi; |
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uint64_t __user *fpregs = sc + abi->off_sc_fpregs; |
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uint32_t __user *csr = sc + abi->off_sc_fpc_csr; |
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uint32_t __user *used_math = sc + abi->off_sc_used_math; |
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unsigned int used; |
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int err, sig = 0, tmp __maybe_unused; |
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err = __get_user(used, used_math); |
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conditional_used_math(used & USED_FP); |
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/* |
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* The signal handler may have used FPU; give it up if the program |
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* doesn't want it following sigreturn. |
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*/ |
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if (err || !(used & USED_FP)) |
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lose_fpu(0); |
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if (err) |
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return err; |
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if (!(used & USED_FP)) |
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goto fp_done; |
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err = sig = fpcsr_pending(csr); |
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if (err < 0) |
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return err; |
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/* |
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* EVA does not have userland equivalents of ldc1 or sdc1, so we |
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* disable the FPU here such that the code below simply copies to |
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* the kernel FP context. |
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*/ |
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if (IS_ENABLED(CONFIG_EVA)) |
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lose_fpu(0); |
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while (1) { |
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lock_fpu_owner(); |
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if (is_fpu_owner()) { |
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err = restore_fp_context(sc); |
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unlock_fpu_owner(); |
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} else { |
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unlock_fpu_owner(); |
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err = copy_fp_from_sigcontext(sc); |
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} |
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if (likely(!err)) |
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break; |
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/* touch the sigcontext and try again */ |
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err = __get_user(tmp, &fpregs[0]) | |
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__get_user(tmp, &fpregs[31]) | |
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__get_user(tmp, csr); |
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if (err) |
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break; /* really bad sigcontext */ |
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} |
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fp_done: |
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if (!err && (used & USED_EXTCONTEXT)) |
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err = restore_extcontext(sc_to_extcontext(sc)); |
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return err ?: sig; |
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} |
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int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) |
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{ |
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int err = 0; |
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int i; |
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err |= __put_user(regs->cp0_epc, &sc->sc_pc); |
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err |= __put_user(0, &sc->sc_regs[0]); |
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for (i = 1; i < 32; i++) |
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err |= __put_user(regs->regs[i], &sc->sc_regs[i]); |
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#ifdef CONFIG_CPU_HAS_SMARTMIPS |
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err |= __put_user(regs->acx, &sc->sc_acx); |
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#endif |
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err |= __put_user(regs->hi, &sc->sc_mdhi); |
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err |= __put_user(regs->lo, &sc->sc_mdlo); |
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if (cpu_has_dsp) { |
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err |= __put_user(mfhi1(), &sc->sc_hi1); |
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err |= __put_user(mflo1(), &sc->sc_lo1); |
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err |= __put_user(mfhi2(), &sc->sc_hi2); |
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err |= __put_user(mflo2(), &sc->sc_lo2); |
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err |= __put_user(mfhi3(), &sc->sc_hi3); |
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err |= __put_user(mflo3(), &sc->sc_lo3); |
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err |= __put_user(rddsp(DSP_MASK), &sc->sc_dsp); |
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} |
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/* |
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* Save FPU state to signal context. Signal handler |
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* will "inherit" current FPU state. |
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*/ |
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err |= protected_save_fp_context(sc); |
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return err; |
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} |
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static size_t extcontext_max_size(void) |
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{ |
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size_t sz = 0; |
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/* |
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* The assumption here is that between this point & the point at which |
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* the extended context is saved the size of the context should only |
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* ever be able to shrink (if the task is preempted), but never grow. |
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* That is, what this function returns is an upper bound on the size of |
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* the extended context for the current task at the current time. |
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*/ |
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if (thread_msa_context_live()) |
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sz += sizeof(struct msa_extcontext); |
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/* If any context is saved then we'll append the end marker */ |
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if (sz) |
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sz += sizeof(((struct extcontext *)NULL)->magic); |
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return sz; |
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} |
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int fpcsr_pending(unsigned int __user *fpcsr) |
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{ |
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int err, sig = 0; |
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unsigned int csr, enabled; |
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err = __get_user(csr, fpcsr); |
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enabled = FPU_CSR_UNI_X | ((csr & FPU_CSR_ALL_E) << 5); |
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/* |
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* If the signal handler set some FPU exceptions, clear it and |
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* send SIGFPE. |
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*/ |
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if (csr & enabled) { |
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csr &= ~enabled; |
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err |= __put_user(csr, fpcsr); |
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sig = SIGFPE; |
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} |
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return err ?: sig; |
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} |
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int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc) |
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{ |
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unsigned long treg; |
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int err = 0; |
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int i; |
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/* Always make any pending restarted system calls return -EINTR */ |
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current->restart_block.fn = do_no_restart_syscall; |
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err |= __get_user(regs->cp0_epc, &sc->sc_pc); |
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#ifdef CONFIG_CPU_HAS_SMARTMIPS |
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err |= __get_user(regs->acx, &sc->sc_acx); |
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#endif |
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err |= __get_user(regs->hi, &sc->sc_mdhi); |
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err |= __get_user(regs->lo, &sc->sc_mdlo); |
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if (cpu_has_dsp) { |
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err |= __get_user(treg, &sc->sc_hi1); mthi1(treg); |
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err |= __get_user(treg, &sc->sc_lo1); mtlo1(treg); |
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err |= __get_user(treg, &sc->sc_hi2); mthi2(treg); |
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err |= __get_user(treg, &sc->sc_lo2); mtlo2(treg); |
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err |= __get_user(treg, &sc->sc_hi3); mthi3(treg); |
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err |= __get_user(treg, &sc->sc_lo3); mtlo3(treg); |
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err |= __get_user(treg, &sc->sc_dsp); wrdsp(treg, DSP_MASK); |
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} |
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for (i = 1; i < 32; i++) |
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err |= __get_user(regs->regs[i], &sc->sc_regs[i]); |
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return err ?: protected_restore_fp_context(sc); |
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} |
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#ifdef CONFIG_WAR_ICACHE_REFILLS |
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#define SIGMASK ~(cpu_icache_line_size()-1) |
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#else |
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#define SIGMASK ALMASK |
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#endif |
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void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, |
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size_t frame_size) |
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{ |
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unsigned long sp; |
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|
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/* Leave space for potential extended context */ |
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frame_size += extcontext_max_size(); |
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|
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/* Default to using normal stack */ |
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sp = regs->regs[29]; |
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|
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/* |
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* FPU emulator may have it's own trampoline active just |
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* above the user stack, 16-bytes before the next lowest |
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* 16 byte boundary. Try to avoid trashing it. |
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*/ |
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sp -= 32; |
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sp = sigsp(sp, ksig); |
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|
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return (void __user *)((sp - frame_size) & SIGMASK); |
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} |
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|
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/* |
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* Atomically swap in the new signal mask, and wait for a signal. |
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*/ |
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|
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#ifdef CONFIG_TRAD_SIGNALS |
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SYSCALL_DEFINE1(sigsuspend, sigset_t __user *, uset) |
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{ |
|
return sys_rt_sigsuspend(uset, sizeof(sigset_t)); |
|
} |
|
#endif |
|
|
|
#ifdef CONFIG_TRAD_SIGNALS |
|
SYSCALL_DEFINE3(sigaction, int, sig, const struct sigaction __user *, act, |
|
struct sigaction __user *, oact) |
|
{ |
|
struct k_sigaction new_ka, old_ka; |
|
int ret; |
|
int err = 0; |
|
|
|
if (act) { |
|
old_sigset_t mask; |
|
|
|
if (!access_ok(act, sizeof(*act))) |
|
return -EFAULT; |
|
err |= __get_user(new_ka.sa.sa_handler, &act->sa_handler); |
|
err |= __get_user(new_ka.sa.sa_flags, &act->sa_flags); |
|
err |= __get_user(mask, &act->sa_mask.sig[0]); |
|
if (err) |
|
return -EFAULT; |
|
|
|
siginitset(&new_ka.sa.sa_mask, mask); |
|
} |
|
|
|
ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); |
|
|
|
if (!ret && oact) { |
|
if (!access_ok(oact, sizeof(*oact))) |
|
return -EFAULT; |
|
err |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags); |
|
err |= __put_user(old_ka.sa.sa_handler, &oact->sa_handler); |
|
err |= __put_user(old_ka.sa.sa_mask.sig[0], oact->sa_mask.sig); |
|
err |= __put_user(0, &oact->sa_mask.sig[1]); |
|
err |= __put_user(0, &oact->sa_mask.sig[2]); |
|
err |= __put_user(0, &oact->sa_mask.sig[3]); |
|
if (err) |
|
return -EFAULT; |
|
} |
|
|
|
return ret; |
|
} |
|
#endif |
|
|
|
#ifdef CONFIG_TRAD_SIGNALS |
|
asmlinkage void sys_sigreturn(void) |
|
{ |
|
struct sigframe __user *frame; |
|
struct pt_regs *regs; |
|
sigset_t blocked; |
|
int sig; |
|
|
|
regs = current_pt_regs(); |
|
frame = (struct sigframe __user *)regs->regs[29]; |
|
if (!access_ok(frame, sizeof(*frame))) |
|
goto badframe; |
|
if (__copy_from_user(&blocked, &frame->sf_mask, sizeof(blocked))) |
|
goto badframe; |
|
|
|
set_current_blocked(&blocked); |
|
|
|
sig = restore_sigcontext(regs, &frame->sf_sc); |
|
if (sig < 0) |
|
goto badframe; |
|
else if (sig) |
|
force_sig(sig); |
|
|
|
/* |
|
* Don't let your children do this ... |
|
*/ |
|
__asm__ __volatile__( |
|
"move\t$29, %0\n\t" |
|
"j\tsyscall_exit" |
|
: /* no outputs */ |
|
: "r" (regs)); |
|
/* Unreached */ |
|
|
|
badframe: |
|
force_sig(SIGSEGV); |
|
} |
|
#endif /* CONFIG_TRAD_SIGNALS */ |
|
|
|
asmlinkage void sys_rt_sigreturn(void) |
|
{ |
|
struct rt_sigframe __user *frame; |
|
struct pt_regs *regs; |
|
sigset_t set; |
|
int sig; |
|
|
|
regs = current_pt_regs(); |
|
frame = (struct rt_sigframe __user *)regs->regs[29]; |
|
if (!access_ok(frame, sizeof(*frame))) |
|
goto badframe; |
|
if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set))) |
|
goto badframe; |
|
|
|
set_current_blocked(&set); |
|
|
|
sig = restore_sigcontext(regs, &frame->rs_uc.uc_mcontext); |
|
if (sig < 0) |
|
goto badframe; |
|
else if (sig) |
|
force_sig(sig); |
|
|
|
if (restore_altstack(&frame->rs_uc.uc_stack)) |
|
goto badframe; |
|
|
|
/* |
|
* Don't let your children do this ... |
|
*/ |
|
__asm__ __volatile__( |
|
"move\t$29, %0\n\t" |
|
"j\tsyscall_exit" |
|
: /* no outputs */ |
|
: "r" (regs)); |
|
/* Unreached */ |
|
|
|
badframe: |
|
force_sig(SIGSEGV); |
|
} |
|
|
|
#ifdef CONFIG_TRAD_SIGNALS |
|
static int setup_frame(void *sig_return, struct ksignal *ksig, |
|
struct pt_regs *regs, sigset_t *set) |
|
{ |
|
struct sigframe __user *frame; |
|
int err = 0; |
|
|
|
frame = get_sigframe(ksig, regs, sizeof(*frame)); |
|
if (!access_ok(frame, sizeof (*frame))) |
|
return -EFAULT; |
|
|
|
err |= setup_sigcontext(regs, &frame->sf_sc); |
|
err |= __copy_to_user(&frame->sf_mask, set, sizeof(*set)); |
|
if (err) |
|
return -EFAULT; |
|
|
|
/* |
|
* Arguments to signal handler: |
|
* |
|
* a0 = signal number |
|
* a1 = 0 (should be cause) |
|
* a2 = pointer to struct sigcontext |
|
* |
|
* $25 and c0_epc point to the signal handler, $29 points to the |
|
* struct sigframe. |
|
*/ |
|
regs->regs[ 4] = ksig->sig; |
|
regs->regs[ 5] = 0; |
|
regs->regs[ 6] = (unsigned long) &frame->sf_sc; |
|
regs->regs[29] = (unsigned long) frame; |
|
regs->regs[31] = (unsigned long) sig_return; |
|
regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler; |
|
|
|
DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n", |
|
current->comm, current->pid, |
|
frame, regs->cp0_epc, regs->regs[31]); |
|
return 0; |
|
} |
|
#endif |
|
|
|
static int setup_rt_frame(void *sig_return, struct ksignal *ksig, |
|
struct pt_regs *regs, sigset_t *set) |
|
{ |
|
struct rt_sigframe __user *frame; |
|
int err = 0; |
|
|
|
frame = get_sigframe(ksig, regs, sizeof(*frame)); |
|
if (!access_ok(frame, sizeof (*frame))) |
|
return -EFAULT; |
|
|
|
/* Create siginfo. */ |
|
err |= copy_siginfo_to_user(&frame->rs_info, &ksig->info); |
|
|
|
/* Create the ucontext. */ |
|
err |= __put_user(0, &frame->rs_uc.uc_flags); |
|
err |= __put_user(NULL, &frame->rs_uc.uc_link); |
|
err |= __save_altstack(&frame->rs_uc.uc_stack, regs->regs[29]); |
|
err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext); |
|
err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set)); |
|
|
|
if (err) |
|
return -EFAULT; |
|
|
|
/* |
|
* Arguments to signal handler: |
|
* |
|
* a0 = signal number |
|
* a1 = 0 (should be cause) |
|
* a2 = pointer to ucontext |
|
* |
|
* $25 and c0_epc point to the signal handler, $29 points to |
|
* the struct rt_sigframe. |
|
*/ |
|
regs->regs[ 4] = ksig->sig; |
|
regs->regs[ 5] = (unsigned long) &frame->rs_info; |
|
regs->regs[ 6] = (unsigned long) &frame->rs_uc; |
|
regs->regs[29] = (unsigned long) frame; |
|
regs->regs[31] = (unsigned long) sig_return; |
|
regs->cp0_epc = regs->regs[25] = (unsigned long) ksig->ka.sa.sa_handler; |
|
|
|
DEBUGP("SIG deliver (%s:%d): sp=0x%p pc=0x%lx ra=0x%lx\n", |
|
current->comm, current->pid, |
|
frame, regs->cp0_epc, regs->regs[31]); |
|
|
|
return 0; |
|
} |
|
|
|
struct mips_abi mips_abi = { |
|
#ifdef CONFIG_TRAD_SIGNALS |
|
.setup_frame = setup_frame, |
|
#endif |
|
.setup_rt_frame = setup_rt_frame, |
|
.restart = __NR_restart_syscall, |
|
|
|
.off_sc_fpregs = offsetof(struct sigcontext, sc_fpregs), |
|
.off_sc_fpc_csr = offsetof(struct sigcontext, sc_fpc_csr), |
|
.off_sc_used_math = offsetof(struct sigcontext, sc_used_math), |
|
|
|
.vdso = &vdso_image, |
|
}; |
|
|
|
static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) |
|
{ |
|
sigset_t *oldset = sigmask_to_save(); |
|
int ret; |
|
struct mips_abi *abi = current->thread.abi; |
|
void *vdso = current->mm->context.vdso; |
|
|
|
/* |
|
* If we were emulating a delay slot instruction, exit that frame such |
|
* that addresses in the sigframe are as expected for userland and we |
|
* don't have a problem if we reuse the thread's frame for an |
|
* instruction within the signal handler. |
|
*/ |
|
dsemul_thread_rollback(regs); |
|
|
|
if (regs->regs[0]) { |
|
switch(regs->regs[2]) { |
|
case ERESTART_RESTARTBLOCK: |
|
case ERESTARTNOHAND: |
|
regs->regs[2] = EINTR; |
|
break; |
|
case ERESTARTSYS: |
|
if (!(ksig->ka.sa.sa_flags & SA_RESTART)) { |
|
regs->regs[2] = EINTR; |
|
break; |
|
} |
|
fallthrough; |
|
case ERESTARTNOINTR: |
|
regs->regs[7] = regs->regs[26]; |
|
regs->regs[2] = regs->regs[0]; |
|
regs->cp0_epc -= 4; |
|
} |
|
|
|
regs->regs[0] = 0; /* Don't deal with this again. */ |
|
} |
|
|
|
rseq_signal_deliver(ksig, regs); |
|
|
|
if (sig_uses_siginfo(&ksig->ka, abi)) |
|
ret = abi->setup_rt_frame(vdso + abi->vdso->off_rt_sigreturn, |
|
ksig, regs, oldset); |
|
else |
|
ret = abi->setup_frame(vdso + abi->vdso->off_sigreturn, |
|
ksig, regs, oldset); |
|
|
|
signal_setup_done(ret, ksig, 0); |
|
} |
|
|
|
static void do_signal(struct pt_regs *regs) |
|
{ |
|
struct ksignal ksig; |
|
|
|
if (get_signal(&ksig)) { |
|
/* Whee! Actually deliver the signal. */ |
|
handle_signal(&ksig, regs); |
|
return; |
|
} |
|
|
|
if (regs->regs[0]) { |
|
switch (regs->regs[2]) { |
|
case ERESTARTNOHAND: |
|
case ERESTARTSYS: |
|
case ERESTARTNOINTR: |
|
regs->regs[2] = regs->regs[0]; |
|
regs->regs[7] = regs->regs[26]; |
|
regs->cp0_epc -= 4; |
|
break; |
|
|
|
case ERESTART_RESTARTBLOCK: |
|
regs->regs[2] = current->thread.abi->restart; |
|
regs->regs[7] = regs->regs[26]; |
|
regs->cp0_epc -= 4; |
|
break; |
|
} |
|
regs->regs[0] = 0; /* Don't deal with this again. */ |
|
} |
|
|
|
/* |
|
* If there's no signal to deliver, we just put the saved sigmask |
|
* back |
|
*/ |
|
restore_saved_sigmask(); |
|
} |
|
|
|
/* |
|
* notification of userspace execution resumption |
|
* - triggered by the TIF_WORK_MASK flags |
|
*/ |
|
asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused, |
|
__u32 thread_info_flags) |
|
{ |
|
local_irq_enable(); |
|
|
|
user_exit(); |
|
|
|
if (thread_info_flags & _TIF_UPROBE) |
|
uprobe_notify_resume(regs); |
|
|
|
/* deal with pending signal delivery */ |
|
if (thread_info_flags & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) |
|
do_signal(regs); |
|
|
|
if (thread_info_flags & _TIF_NOTIFY_RESUME) |
|
tracehook_notify_resume(regs); |
|
|
|
user_enter(); |
|
} |
|
|
|
#if defined(CONFIG_SMP) && defined(CONFIG_MIPS_FP_SUPPORT) |
|
static int smp_save_fp_context(void __user *sc) |
|
{ |
|
return raw_cpu_has_fpu |
|
? save_hw_fp_context(sc) |
|
: copy_fp_to_sigcontext(sc); |
|
} |
|
|
|
static int smp_restore_fp_context(void __user *sc) |
|
{ |
|
return raw_cpu_has_fpu |
|
? restore_hw_fp_context(sc) |
|
: copy_fp_from_sigcontext(sc); |
|
} |
|
#endif |
|
|
|
static int signal_setup(void) |
|
{ |
|
/* |
|
* The offset from sigcontext to extended context should be the same |
|
* regardless of the type of signal, such that userland can always know |
|
* where to look if it wishes to find the extended context structures. |
|
*/ |
|
BUILD_BUG_ON((offsetof(struct sigframe, sf_extcontext) - |
|
offsetof(struct sigframe, sf_sc)) != |
|
(offsetof(struct rt_sigframe, rs_uc.uc_extcontext) - |
|
offsetof(struct rt_sigframe, rs_uc.uc_mcontext))); |
|
|
|
#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; |
|
#else |
|
if (cpu_has_fpu) { |
|
save_fp_context = save_hw_fp_context; |
|
restore_fp_context = restore_hw_fp_context; |
|
} else { |
|
save_fp_context = copy_fp_to_sigcontext; |
|
restore_fp_context = copy_fp_from_sigcontext; |
|
} |
|
#endif /* CONFIG_SMP */ |
|
|
|
return 0; |
|
} |
|
|
|
arch_initcall(signal_setup);
|
|
|