Commit 2db9ca0a authored by Paul Burton's avatar Paul Burton Committed by Ralf Baechle
Browse files

MIPS: Use struct mips_abi offsets to save FP context 



When saving FP state to struct sigcontext, make use of the offsets
provided by struct mips_abi to obtain appropriate addresses for the
sc_fpregs & sc_fpc_csr fields of the sigcontext. This is done only for
the native struct sigcontext in this patch (ie. for O32 in CONFIG_32BIT
kernels or for N64 in CONFIG_64BIT kernels) but is done in preparation
for sharing this code with compat ABIs in further patches.

Signed-off-by: default avatarPaul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Matthew Fortune <matthew.fortune@imgtec.com>
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: linux-kernel@vger.kernel.org
Cc: Richard Weinberger <richard@nod.at>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Manuel Lauss <manuel.lauss@gmail.com>
Cc: Maciej W. Rozycki <macro@codesourcery.com>
Patchwork: https://patchwork.linux-mips.org/patch/10789/


Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
parent 77856100

arch/mips/kernel/r4k_fpu.S

+81 −70
Original line number Diff line number Diff line
@@ -36,6 +36,14 @@ 


	.set	noreorder



/**

 * _save_fp_context() - save FP context from the FPU

 * @a0 - pointer to fpregs field of sigcontext

 * @a1 - pointer to fpc_csr field of sigcontext

 *

 * Save FP context, including the 32 FP data registers and the FP

 * control & status register, from the FPU to signal context.

 */

LEAF(_save_fp_context)

	.set	push

	SET_HARDFLOAT
@@ -55,45 +63,45 @@ LEAF(_save_fp_context) 
	 nop

#endif

	/* Store the 16 odd double precision registers */

	EX	sdc1 $f1, SC_FPREGS+8(a0)

	EX	sdc1 $f3, SC_FPREGS+24(a0)

	EX	sdc1 $f5, SC_FPREGS+40(a0)

	EX	sdc1 $f7, SC_FPREGS+56(a0)

	EX	sdc1 $f9, SC_FPREGS+72(a0)

	EX	sdc1 $f11, SC_FPREGS+88(a0)

	EX	sdc1 $f13, SC_FPREGS+104(a0)

	EX	sdc1 $f15, SC_FPREGS+120(a0)

	EX	sdc1 $f17, SC_FPREGS+136(a0)

	EX	sdc1 $f19, SC_FPREGS+152(a0)

	EX	sdc1 $f21, SC_FPREGS+168(a0)

	EX	sdc1 $f23, SC_FPREGS+184(a0)

	EX	sdc1 $f25, SC_FPREGS+200(a0)

	EX	sdc1 $f27, SC_FPREGS+216(a0)

	EX	sdc1 $f29, SC_FPREGS+232(a0)

	EX	sdc1 $f31, SC_FPREGS+248(a0)

	EX	sdc1 $f1, 8(a0)

	EX	sdc1 $f3, 24(a0)

	EX	sdc1 $f5, 40(a0)

	EX	sdc1 $f7, 56(a0)

	EX	sdc1 $f9, 72(a0)

	EX	sdc1 $f11, 88(a0)

	EX	sdc1 $f13, 104(a0)

	EX	sdc1 $f15, 120(a0)

	EX	sdc1 $f17, 136(a0)

	EX	sdc1 $f19, 152(a0)

	EX	sdc1 $f21, 168(a0)

	EX	sdc1 $f23, 184(a0)

	EX	sdc1 $f25, 200(a0)

	EX	sdc1 $f27, 216(a0)

	EX	sdc1 $f29, 232(a0)

	EX	sdc1 $f31, 248(a0)

1:	.set	pop

#endif



	.set push

	SET_HARDFLOAT

	/* Store the 16 even double precision registers */

	EX	sdc1 $f0, SC_FPREGS+0(a0)

	EX	sdc1 $f2, SC_FPREGS+16(a0)

	EX	sdc1 $f4, SC_FPREGS+32(a0)

	EX	sdc1 $f6, SC_FPREGS+48(a0)

	EX	sdc1 $f8, SC_FPREGS+64(a0)

	EX	sdc1 $f10, SC_FPREGS+80(a0)

	EX	sdc1 $f12, SC_FPREGS+96(a0)

	EX	sdc1 $f14, SC_FPREGS+112(a0)

	EX	sdc1 $f16, SC_FPREGS+128(a0)

	EX	sdc1 $f18, SC_FPREGS+144(a0)

	EX	sdc1 $f20, SC_FPREGS+160(a0)

	EX	sdc1 $f22, SC_FPREGS+176(a0)

	EX	sdc1 $f24, SC_FPREGS+192(a0)

	EX	sdc1 $f26, SC_FPREGS+208(a0)

	EX	sdc1 $f28, SC_FPREGS+224(a0)

	EX	sdc1 $f30, SC_FPREGS+240(a0)

	EX	sw t1, SC_FPC_CSR(a0)

	EX	sdc1 $f0, 0(a0)

	EX	sdc1 $f2, 16(a0)

	EX	sdc1 $f4, 32(a0)

	EX	sdc1 $f6, 48(a0)

	EX	sdc1 $f8, 64(a0)

	EX	sdc1 $f10, 80(a0)

	EX	sdc1 $f12, 96(a0)

	EX	sdc1 $f14, 112(a0)

	EX	sdc1 $f16, 128(a0)

	EX	sdc1 $f18, 144(a0)

	EX	sdc1 $f20, 160(a0)

	EX	sdc1 $f22, 176(a0)

	EX	sdc1 $f24, 192(a0)

	EX	sdc1 $f26, 208(a0)

	EX	sdc1 $f28, 224(a0)

	EX	sdc1 $f30, 240(a0)

	EX	sw t1, 0(a1)

	jr	ra

	 li	v0, 0					# success

	.set pop
@@ -159,13 +167,16 @@ LEAF(_save_fp_context32) 
	END(_save_fp_context32)

#endif



/*

 * Restore FPU state:

 *  - fp gp registers

 *  - cp1 status/control register

/**

 * _restore_fp_context() - restore FP context to the FPU

 * @a0 - pointer to fpregs field of sigcontext

 * @a1 - pointer to fpc_csr field of sigcontext

 *

 * Restore FP context, including the 32 FP data registers and the FP

 * control & status register, from signal context to the FPU.

 */

LEAF(_restore_fp_context)

	EX	lw t1, SC_FPC_CSR(a0)

	EX	lw t1, 0(a1)



#if defined(CONFIG_64BIT) || defined(CONFIG_CPU_MIPS32_R2)  || \

		defined(CONFIG_CPU_MIPS32_R6)
@@ -179,42 +190,42 @@ LEAF(_restore_fp_context) 
	bgez	t0, 1f			# skip loading odd if FR=0

	 nop

#endif

	EX	ldc1 $f1, SC_FPREGS+8(a0)

	EX	ldc1 $f3, SC_FPREGS+24(a0)

	EX	ldc1 $f5, SC_FPREGS+40(a0)

	EX	ldc1 $f7, SC_FPREGS+56(a0)

	EX	ldc1 $f9, SC_FPREGS+72(a0)

	EX	ldc1 $f11, SC_FPREGS+88(a0)

	EX	ldc1 $f13, SC_FPREGS+104(a0)

	EX	ldc1 $f15, SC_FPREGS+120(a0)

	EX	ldc1 $f17, SC_FPREGS+136(a0)

	EX	ldc1 $f19, SC_FPREGS+152(a0)

	EX	ldc1 $f21, SC_FPREGS+168(a0)

	EX	ldc1 $f23, SC_FPREGS+184(a0)

	EX	ldc1 $f25, SC_FPREGS+200(a0)

	EX	ldc1 $f27, SC_FPREGS+216(a0)

	EX	ldc1 $f29, SC_FPREGS+232(a0)

	EX	ldc1 $f31, SC_FPREGS+248(a0)

	EX	ldc1 $f1, 8(a0)

	EX	ldc1 $f3, 24(a0)

	EX	ldc1 $f5, 40(a0)

	EX	ldc1 $f7, 56(a0)

	EX	ldc1 $f9, 72(a0)

	EX	ldc1 $f11, 88(a0)

	EX	ldc1 $f13, 104(a0)

	EX	ldc1 $f15, 120(a0)

	EX	ldc1 $f17, 136(a0)

	EX	ldc1 $f19, 152(a0)

	EX	ldc1 $f21, 168(a0)

	EX	ldc1 $f23, 184(a0)

	EX	ldc1 $f25, 200(a0)

	EX	ldc1 $f27, 216(a0)

	EX	ldc1 $f29, 232(a0)

	EX	ldc1 $f31, 248(a0)

1:	.set pop

#endif

	.set push

	SET_HARDFLOAT

	EX	ldc1 $f0, SC_FPREGS+0(a0)

	EX	ldc1 $f2, SC_FPREGS+16(a0)

	EX	ldc1 $f4, SC_FPREGS+32(a0)

	EX	ldc1 $f6, SC_FPREGS+48(a0)

	EX	ldc1 $f8, SC_FPREGS+64(a0)

	EX	ldc1 $f10, SC_FPREGS+80(a0)

	EX	ldc1 $f12, SC_FPREGS+96(a0)

	EX	ldc1 $f14, SC_FPREGS+112(a0)

	EX	ldc1 $f16, SC_FPREGS+128(a0)

	EX	ldc1 $f18, SC_FPREGS+144(a0)

	EX	ldc1 $f20, SC_FPREGS+160(a0)

	EX	ldc1 $f22, SC_FPREGS+176(a0)

	EX	ldc1 $f24, SC_FPREGS+192(a0)

	EX	ldc1 $f26, SC_FPREGS+208(a0)

	EX	ldc1 $f28, SC_FPREGS+224(a0)

	EX	ldc1 $f30, SC_FPREGS+240(a0)

	EX	ldc1 $f0, 0(a0)

	EX	ldc1 $f2, 16(a0)

	EX	ldc1 $f4, 32(a0)

	EX	ldc1 $f6, 48(a0)

	EX	ldc1 $f8, 64(a0)

	EX	ldc1 $f10, 80(a0)

	EX	ldc1 $f12, 96(a0)

	EX	ldc1 $f14, 112(a0)

	EX	ldc1 $f16, 128(a0)

	EX	ldc1 $f18, 144(a0)

	EX	ldc1 $f20, 160(a0)

	EX	ldc1 $f22, 176(a0)

	EX	ldc1 $f24, 192(a0)

	EX	ldc1 $f26, 208(a0)

	EX	ldc1 $f28, 224(a0)

	EX	ldc1 $f30, 240(a0)

	ctc1	t1, fcr31

	.set pop

	jr	ra

arch/mips/kernel/signal-common.h

+6 −0
Original line number Diff line number Diff line
@@ -31,4 +31,10 @@ extern int fpcsr_pending(unsigned int __user *fpcsr); 
#define lock_fpu_owner()	({ preempt_disable(); pagefault_disable(); })

#define unlock_fpu_owner()	({ pagefault_enable(); preempt_enable(); })



/* Assembly functions to move context to/from the FPU */

extern asmlinkage int

_save_fp_context(void __user *fpregs, void __user *csr);

extern asmlinkage int

_restore_fp_context(void __user *fpregs, void __user *csr);



#endif	/* __SIGNAL_COMMON_H */

arch/mips/kernel/signal.c

+58 −27
Original line number Diff line number Diff line
@@ -41,11 +41,8 @@ 


#include "signal-common.h"



static int (*save_fp_context)(struct sigcontext __user *sc);

static int (*restore_fp_context)(struct sigcontext __user *sc);



extern asmlinkage int _save_fp_context(struct sigcontext __user *sc);

extern asmlinkage int _restore_fp_context(struct sigcontext __user *sc);

static int (*save_fp_context)(void __user *sc);

static int (*restore_fp_context)(void __user *sc);



struct sigframe {

	u32 sf_ass[4];		/* argument save space for o32 */
@@ -65,41 +62,71 @@ struct rt_sigframe { 
 * 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.

 */

static int copy_fp_to_sigcontext(struct sigcontext __user *sc)

static int copy_fp_to_sigcontext(void __user *sc)

{

	struct mips_abi *abi = current->thread.abi;

	uint64_t __user *fpregs = sc + abi->off_sc_fpregs;

	uint32_t __user *csr = sc + abi->off_sc_fpc_csr;

	int i;

	int err = 0;



	for (i = 0; i < NUM_FPU_REGS; i++) {

		err |=

		    __put_user(get_fpr64(&current->thread.fpu.fpr[i], 0),

			       &sc->sc_fpregs[i]);

			       &fpregs[i]);

	}

	err |= __put_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);

	err |= __put_user(current->thread.fpu.fcr31, csr);



	return err;

}



static int copy_fp_from_sigcontext(struct sigcontext __user *sc)

static int copy_fp_from_sigcontext(void __user *sc)

{

	struct mips_abi *abi = current->thread.abi;

	uint64_t __user *fpregs = sc + abi->off_sc_fpregs;

	uint32_t __user *csr = sc + abi->off_sc_fpc_csr;

	int i;

	int err = 0;

	u64 fpr_val;



	for (i = 0; i < NUM_FPU_REGS; i++) {

		err |= __get_user(fpr_val, &sc->sc_fpregs[i]);

		err |= __get_user(fpr_val, &fpregs[i]);

		set_fpr64(&current->thread.fpu.fpr[i], 0, fpr_val);

	}

	err |= __get_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);

	err |= __get_user(current->thread.fpu.fcr31, csr);



	return err;

}



/*

 * Wrappers for the assembly _{save,restore}_fp_context functions.

 */

static int save_hw_fp_context(void __user *sc)

{

	struct mips_abi *abi = current->thread.abi;

	uint64_t __user *fpregs = sc + abi->off_sc_fpregs;

	uint32_t __user *csr = sc + abi->off_sc_fpc_csr;



	return _save_fp_context(fpregs, csr);

}



static int restore_hw_fp_context(void __user *sc)

{

	struct mips_abi *abi = current->thread.abi;

	uint64_t __user *fpregs = sc + abi->off_sc_fpregs;

	uint32_t __user *csr = sc + abi->off_sc_fpc_csr;



	return _restore_fp_context(fpregs, csr);

}



/*

 * Helper routines

 */

static int protected_save_fp_context(struct sigcontext __user *sc)

static int protected_save_fp_context(void __user *sc)

{

	struct mips_abi *abi = current->thread.abi;

	uint64_t __user *fpregs = sc + abi->off_sc_fpregs;

	uint32_t __user *csr = sc + abi->off_sc_fpc_csr;

	int err;



	/*
@@ -121,9 +148,9 @@ static int protected_save_fp_context(struct sigcontext __user *sc) 
		if (likely(!err))

			break;

		/* touch the sigcontext and try again */

		err = __put_user(0, &sc->sc_fpregs[0]) |

			__put_user(0, &sc->sc_fpregs[31]) |

			__put_user(0, &sc->sc_fpc_csr);

		err = __put_user(0, &fpregs[0]) |

			__put_user(0, &fpregs[31]) |

			__put_user(0, csr);

		if (err)

			break;	/* really bad sigcontext */

	}
@@ -131,8 +158,11 @@ static int protected_save_fp_context(struct sigcontext __user *sc) 
	return err;

}



static int protected_restore_fp_context(struct sigcontext __user *sc)

static int protected_restore_fp_context(void __user *sc)

{

	struct mips_abi *abi = current->thread.abi;

	uint64_t __user *fpregs = sc + abi->off_sc_fpregs;

	uint32_t __user *csr = sc + abi->off_sc_fpc_csr;

	int err, tmp __maybe_unused;



	/*
@@ -155,9 +185,9 @@ static int protected_restore_fp_context(struct sigcontext __user *sc) 
		if (likely(!err))

			break;

		/* touch the sigcontext and try again */

		err = __get_user(tmp, &sc->sc_fpregs[0]) |

			__get_user(tmp, &sc->sc_fpregs[31]) |

			__get_user(tmp, &sc->sc_fpc_csr);

		err = __get_user(tmp, &fpregs[0]) |

			__get_user(tmp, &fpregs[31]) |

			__get_user(tmp, csr);

		if (err)

			break;	/* really bad sigcontext */

	}
@@ -225,11 +255,12 @@ int fpcsr_pending(unsigned int __user *fpcsr) 
}



static int

check_and_restore_fp_context(struct sigcontext __user *sc)

check_and_restore_fp_context(void __user *sc)

{

	struct mips_abi *abi = current->thread.abi;

	int err, sig;



	err = sig = fpcsr_pending(&sc->sc_fpc_csr);

	err = sig = fpcsr_pending(sc + abi->off_sc_fpc_csr);

	if (err > 0)

		err = 0;

	err |= protected_restore_fp_context(sc);
@@ -634,17 +665,17 @@ asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused, 
}



#ifdef CONFIG_SMP

static int smp_save_fp_context(struct sigcontext __user *sc)

static int smp_save_fp_context(void __user *sc)

{

	return raw_cpu_has_fpu

	       ? _save_fp_context(sc)

	       ? save_hw_fp_context(sc)

	       : copy_fp_to_sigcontext(sc);

}



static int smp_restore_fp_context(struct sigcontext __user *sc)

static int smp_restore_fp_context(void __user *sc)

{

	return raw_cpu_has_fpu

	       ? _restore_fp_context(sc)

	       ? restore_hw_fp_context(sc)

	       : copy_fp_from_sigcontext(sc);

}

#endif
@@ -657,8 +688,8 @@ static int signal_setup(void) 
	restore_fp_context = smp_restore_fp_context;

#else

	if (cpu_has_fpu) {

		save_fp_context = _save_fp_context;

		restore_fp_context = _restore_fp_context;

		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;

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