Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161022Ab3FGXN7 (ORCPT ); Fri, 7 Jun 2013 19:13:59 -0400 Received: from mail-ie0-f176.google.com ([209.85.223.176]:50967 "EHLO mail-ie0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756177Ab3FGXDq (ORCPT ); Fri, 7 Jun 2013 19:03:46 -0400 From: David Daney To: linux-mips@linux-mips.org, ralf@linux-mips.org, kvm@vger.kernel.org, Sanjay Lal Cc: linux-kernel@vger.kernel.org, David Daney Subject: [PATCH 02/31] MIPS: Save and restore K0/K1 when CONFIG_KVM_MIPSVZ Date: Fri, 7 Jun 2013 16:03:06 -0700 Message-Id: <1370646215-6543-3-git-send-email-ddaney.cavm@gmail.com> X-Mailer: git-send-email 1.7.11.7 In-Reply-To: <1370646215-6543-1-git-send-email-ddaney.cavm@gmail.com> References: <1370646215-6543-1-git-send-email-ddaney.cavm@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8323 Lines: 278 From: David Daney We cannot clobber any registers on exceptions as any guest will need them all. Signed-off-by: David Daney --- arch/mips/include/asm/mipsregs.h | 2 ++ arch/mips/include/asm/stackframe.h | 15 +++++++++++++++ arch/mips/kernel/cpu-probe.c | 7 ++++++- arch/mips/kernel/genex.S | 5 +++++ arch/mips/kernel/scall64-64.S | 12 ++++++++++++ arch/mips/kernel/scall64-n32.S | 12 ++++++++++++ arch/mips/kernel/traps.c | 5 +++++ arch/mips/mm/tlbex.c | 25 +++++++++++++++++++++++++ 8 files changed, 82 insertions(+), 1 deletion(-) diff --git a/arch/mips/include/asm/mipsregs.h b/arch/mips/include/asm/mipsregs.h index 6e0da5aa..6f03c72 100644 --- a/arch/mips/include/asm/mipsregs.h +++ b/arch/mips/include/asm/mipsregs.h @@ -73,6 +73,8 @@ #define CP0_TAGHI $29 #define CP0_ERROREPC $30 #define CP0_DESAVE $31 +#define CP0_KSCRATCH1 $31, 2 +#define CP0_KSCRATCH2 $31, 3 /* * R4640/R4650 cp0 register names. These registers are listed diff --git a/arch/mips/include/asm/stackframe.h b/arch/mips/include/asm/stackframe.h index a89d1b1..20627b2 100644 --- a/arch/mips/include/asm/stackframe.h +++ b/arch/mips/include/asm/stackframe.h @@ -181,6 +181,16 @@ #endif LONG_S k0, PT_R29(sp) LONG_S $3, PT_R3(sp) +#ifdef CONFIG_KVM_MIPSVZ + /* + * With KVM_MIPSVZ, we must not clobber k0/k1 + * they were saved before they were used + */ + MFC0 k0, CP0_KSCRATCH1 + MFC0 $3, CP0_KSCRATCH2 + LONG_S k0, PT_R26(sp) + LONG_S $3, PT_R27(sp) +#endif /* * You might think that you don't need to save $0, * but the FPU emulator and gdb remote debug stub @@ -447,6 +457,11 @@ .endm .macro RESTORE_SP_AND_RET + +#ifdef CONFIG_KVM_MIPSVZ + LONG_L k0, PT_R26(sp) + LONG_L k1, PT_R27(sp) +#endif LONG_L sp, PT_R29(sp) .set mips3 eret diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c index ee1014e..7a07edb 100644 --- a/arch/mips/kernel/cpu-probe.c +++ b/arch/mips/kernel/cpu-probe.c @@ -1067,7 +1067,12 @@ __cpuinit void cpu_report(void) static DEFINE_SPINLOCK(kscratch_used_lock); -static unsigned int kscratch_used_mask; +static unsigned int kscratch_used_mask +#ifdef CONFIG_KVM_MIPSVZ +/* KVM_MIPSVZ implemtation uses these two statically. */ += 0xc +#endif +; int allocate_kscratch(void) { diff --git a/arch/mips/kernel/genex.S b/arch/mips/kernel/genex.S index 31fa856..163e299 100644 --- a/arch/mips/kernel/genex.S +++ b/arch/mips/kernel/genex.S @@ -46,6 +46,11 @@ NESTED(except_vec3_generic, 0, sp) .set push .set noat +#ifdef CONFIG_KVM_MIPSVZ + /* With KVM_MIPSVZ, we must not clobber k0/k1 */ + MTC0 k0, CP0_KSCRATCH1 + MTC0 k1, CP0_KSCRATCH2 +#endif #if R5432_CP0_INTERRUPT_WAR mfc0 k0, CP0_INDEX #endif diff --git a/arch/mips/kernel/scall64-64.S b/arch/mips/kernel/scall64-64.S index 97a5909..5ff4882 100644 --- a/arch/mips/kernel/scall64-64.S +++ b/arch/mips/kernel/scall64-64.S @@ -62,6 +62,9 @@ NESTED(handle_sys64, PT_SIZE, sp) jalr t2 # Do The Real Thing (TM) li t0, -EMAXERRNO - 1 # error? +#if defined(CONFIG_KVM_MIPSVZ) && defined(CONFIG_FAST_ACCESS_TO_THREAD_POINTER) + ld t2, TI_TP_VALUE($28) +#endif sltu t0, t0, v0 sd t0, PT_R7(sp) # set error flag beqz t0, 1f @@ -70,6 +73,9 @@ NESTED(handle_sys64, PT_SIZE, sp) dnegu v0 # error sd t1, PT_R0(sp) # save it for syscall restarting 1: sd v0, PT_R2(sp) # result +#if defined(CONFIG_KVM_MIPSVZ) && defined(CONFIG_FAST_ACCESS_TO_THREAD_POINTER) + sd t2, PT_R26(sp) +#endif n64_syscall_exit: j syscall_exit_partial @@ -93,6 +99,9 @@ syscall_trace_entry: jalr t0 li t0, -EMAXERRNO - 1 # error? +#if defined(CONFIG_KVM_MIPSVZ) && defined(CONFIG_FAST_ACCESS_TO_THREAD_POINTER) + ld t2, TI_TP_VALUE($28) +#endif sltu t0, t0, v0 sd t0, PT_R7(sp) # set error flag beqz t0, 1f @@ -101,6 +110,9 @@ syscall_trace_entry: dnegu v0 # error sd t1, PT_R0(sp) # save it for syscall restarting 1: sd v0, PT_R2(sp) # result +#if defined(CONFIG_KVM_MIPSVZ) && defined(CONFIG_FAST_ACCESS_TO_THREAD_POINTER) + sd t2, PT_R26(sp) +#endif j syscall_exit diff --git a/arch/mips/kernel/scall64-n32.S b/arch/mips/kernel/scall64-n32.S index edcb659..cba35b4 100644 --- a/arch/mips/kernel/scall64-n32.S +++ b/arch/mips/kernel/scall64-n32.S @@ -55,6 +55,9 @@ NESTED(handle_sysn32, PT_SIZE, sp) jalr t2 # Do The Real Thing (TM) li t0, -EMAXERRNO - 1 # error? +#if defined(CONFIG_KVM_MIPSVZ) && defined(CONFIG_FAST_ACCESS_TO_THREAD_POINTER) + ld t2, TI_TP_VALUE($28) +#endif sltu t0, t0, v0 sd t0, PT_R7(sp) # set error flag beqz t0, 1f @@ -63,6 +66,9 @@ NESTED(handle_sysn32, PT_SIZE, sp) dnegu v0 # error sd t1, PT_R0(sp) # save it for syscall restarting 1: sd v0, PT_R2(sp) # result +#if defined(CONFIG_KVM_MIPSVZ) && defined(CONFIG_FAST_ACCESS_TO_THREAD_POINTER) + sd t2, PT_R26(sp) +#endif j syscall_exit_partial @@ -85,6 +91,9 @@ n32_syscall_trace_entry: jalr t0 li t0, -EMAXERRNO - 1 # error? +#if defined(CONFIG_KVM_MIPSVZ) && defined(CONFIG_FAST_ACCESS_TO_THREAD_POINTER) + ld t2, TI_TP_VALUE($28) +#endif sltu t0, t0, v0 sd t0, PT_R7(sp) # set error flag beqz t0, 1f @@ -93,6 +102,9 @@ n32_syscall_trace_entry: dnegu v0 # error sd t1, PT_R0(sp) # save it for syscall restarting 1: sd v0, PT_R2(sp) # result +#if defined(CONFIG_KVM_MIPSVZ) && defined(CONFIG_FAST_ACCESS_TO_THREAD_POINTER) + sd t2, PT_R26(sp) +#endif j syscall_exit diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c index e3be670..f008795 100644 --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -1483,6 +1483,11 @@ void __init *set_except_vector(int n, void *addr) #endif u32 *buf = (u32 *)(ebase + 0x200); unsigned int k0 = 26; +#ifdef CONFIG_KVM_MIPSVZ + unsigned int k1 = 27; + UASM_i_MTC0(&buf, k0, 31, 2); + UASM_i_MTC0(&buf, k1, 31, 3); +#endif if ((handler & jump_mask) == ((ebase + 0x200) & jump_mask)) { uasm_i_j(&buf, handler & ~jump_mask); uasm_i_nop(&buf); diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c index 001b87c..3ce7208 100644 --- a/arch/mips/mm/tlbex.c +++ b/arch/mips/mm/tlbex.c @@ -372,11 +372,19 @@ static void __cpuinit build_restore_work_registers(u32 **p) { if (scratch_reg > 0) { UASM_i_MFC0(p, 1, 31, scratch_reg); +#ifdef CONFIG_KVM_MIPSVZ + UASM_i_MFC0(p, K0, 31, 2); + UASM_i_MFC0(p, K1, 31, 3); +#endif return; } /* K0 already points to save area, restore $1 and $2 */ UASM_i_LW(p, 1, offsetof(struct tlb_reg_save, a), K0); UASM_i_LW(p, 2, offsetof(struct tlb_reg_save, b), K0); +#ifdef CONFIG_KVM_MIPSVZ + UASM_i_MFC0(p, K0, 31, 2); + UASM_i_MFC0(p, K1, 31, 3); +#endif } #ifndef CONFIG_MIPS_PGD_C0_CONTEXT @@ -1089,6 +1097,11 @@ build_fast_tlb_refill_handler (u32 **p, struct uasm_label **l, int vmalloc_branch_delay_filled = 0; const int scratch = 1; /* Our extra working register */ +#ifdef CONFIG_KVM_MIPSVZ + UASM_i_MTC0(p, K0, 31, 2); + UASM_i_MTC0(p, K1, 31, 3); +#endif + rv.huge_pte = scratch; rv.restore_scratch = 0; @@ -1244,6 +1257,10 @@ build_fast_tlb_refill_handler (u32 **p, struct uasm_label **l, rv.restore_scratch = 1; } +#ifdef CONFIG_KVM_MIPSVZ + UASM_i_MFC0(p, K0, 31, 2); + UASM_i_MFC0(p, K1, 31, 3); +#endif uasm_i_eret(p); /* return from trap */ return rv; @@ -1277,6 +1294,10 @@ static void __cpuinit build_r4000_tlb_refill_handler(void) scratch_reg); vmalloc_mode = refill_scratch; } else { +#ifdef CONFIG_KVM_MIPSVZ + UASM_i_MTC0(&p, K0, 31, 2); + UASM_i_MTC0(&p, K1, 31, 3); +#endif htlb_info.huge_pte = K0; htlb_info.restore_scratch = 0; vmalloc_mode = refill_noscratch; @@ -1311,6 +1332,10 @@ static void __cpuinit build_r4000_tlb_refill_handler(void) build_update_entries(&p, K0, K1); build_tlb_write_entry(&p, &l, &r, tlb_random); uasm_l_leave(&l, p); +#ifdef CONFIG_KVM_MIPSVZ + UASM_i_MFC0(&p, K0, 31, 2); + UASM_i_MFC0(&p, K1, 31, 3); +#endif uasm_i_eret(&p); /* return from trap */ } #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT -- 1.7.11.7 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/