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linux/arch/arc/include/asm/ptrace.h

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ARC: Fundamental ARCH data-types/defines * L1_CACHE_SHIFT * PAGE_SIZE, PAGE_OFFSET * struct pt_regs, struct user_regs_struct * struct thread_struct, cpu_relax(), task_pt_regs(), start_thread(), ... * struct thread_info, THREAD_SIZE, INIT_THREAD_INFO(), TIF_*, ... * BUG() * ELF_* * Elf_* To disallow user-space visibility into some of the core kernel data-types such as struct pt_regs, #ifdef __KERNEL__ which also makes the UAPI header spit (further patch in the series) to NOT export it to asm/uapi/ptrace.h Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Jonas Bonn <jonas.bonn@gmail.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-01-18 09:42:17 +00:00
/*
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Amit Bhor, Sameer Dhavale: Codito Technologies 2004
*/
#ifndef __ASM_ARC_PTRACE_H
#define __ASM_ARC_PTRACE_H
ARC: UAPI Disintegrate arch/arc/include/asm 1. ./genfilelist.pl arch/arc/include/asm/ 2. Create arch/arc/include/uapi/asm/Kbuild as follows +# UAPI Header export list +include include/uapi/asm-generic/Kbuild.asm 3. ./disintegrate-one.pl arch/arc/include/{,uapi/}asm/<above-list> 4. Edit arch/arc/include/asm/Kbuild to remove ref to asm-generic/Kbuild.asm - To work around empty uapi/asm/setup.h added a placholder comment. - Also a manual #ifdef __ASSEMBLY__ for a late ptrace change Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: David Howells <dhowells@redhat.com>
2013-02-11 14:25:33 +00:00
#include <uapi/asm/ptrace.h>
ARC: Fundamental ARCH data-types/defines * L1_CACHE_SHIFT * PAGE_SIZE, PAGE_OFFSET * struct pt_regs, struct user_regs_struct * struct thread_struct, cpu_relax(), task_pt_regs(), start_thread(), ... * struct thread_info, THREAD_SIZE, INIT_THREAD_INFO(), TIF_*, ... * BUG() * ELF_* * Elf_* To disallow user-space visibility into some of the core kernel data-types such as struct pt_regs, #ifdef __KERNEL__ which also makes the UAPI header spit (further patch in the series) to NOT export it to asm/uapi/ptrace.h Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Jonas Bonn <jonas.bonn@gmail.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-01-18 09:42:17 +00:00
#ifndef __ASSEMBLY__
/* THE pt_regs: Defines how regs are saved during entry into kernel */
struct pt_regs {
/* Real registers */
long bta; /* bta_l1, bta_l2, erbta */
ARC: Code cosmetics (Nothing semantical) * reduce editor lines taken by pt_regs * ARCompact ISA specific part of TLB Miss handlers clubbed together * cleanup some comments Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-07-10 06:10:27 +00:00
long lp_start, lp_end, lp_count;
ARC: Fundamental ARCH data-types/defines * L1_CACHE_SHIFT * PAGE_SIZE, PAGE_OFFSET * struct pt_regs, struct user_regs_struct * struct thread_struct, cpu_relax(), task_pt_regs(), start_thread(), ... * struct thread_info, THREAD_SIZE, INIT_THREAD_INFO(), TIF_*, ... * BUG() * ELF_* * Elf_* To disallow user-space visibility into some of the core kernel data-types such as struct pt_regs, #ifdef __KERNEL__ which also makes the UAPI header spit (further patch in the series) to NOT export it to asm/uapi/ptrace.h Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Jonas Bonn <jonas.bonn@gmail.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-01-18 09:42:17 +00:00
long status32; /* status32_l1, status32_l2, erstatus */
long ret; /* ilink1, ilink2 or eret */
long blink;
long fp;
long r26; /* gp */
ARC: Code cosmetics (Nothing semantical) * reduce editor lines taken by pt_regs * ARCompact ISA specific part of TLB Miss handlers clubbed together * cleanup some comments Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-07-10 06:10:27 +00:00
long r12, r11, r10, r9, r8, r7, r6, r5, r4, r3, r2, r1, r0;
ARC: Fundamental ARCH data-types/defines * L1_CACHE_SHIFT * PAGE_SIZE, PAGE_OFFSET * struct pt_regs, struct user_regs_struct * struct thread_struct, cpu_relax(), task_pt_regs(), start_thread(), ... * struct thread_info, THREAD_SIZE, INIT_THREAD_INFO(), TIF_*, ... * BUG() * ELF_* * Elf_* To disallow user-space visibility into some of the core kernel data-types such as struct pt_regs, #ifdef __KERNEL__ which also makes the UAPI header spit (further patch in the series) to NOT export it to asm/uapi/ptrace.h Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Jonas Bonn <jonas.bonn@gmail.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-01-18 09:42:17 +00:00
long sp; /* user/kernel sp depending on where we came from */
long orig_r0;
ARC: [Review] Preparing to fix incorrect syscall restarts due to signals To avoid multiple syscall restarts (multiple signals) or no restart at all (sigreturn), we need just an extra bit of state "literally 1 bit" in struct pt_regs. orig_r8 is the best place to do this, however given the way it is encoded currently, we can't add anything simplistically. Current orig_r8: * syscalls -> 1 to NR_SYSCALLS * Exceptions -> NR_SYSCALLS + 1 * Break-point-> NR_SYSCALLS + 2 In new scheme it is a bit-field * lower short word contains the exact event type (and a new bit to represent restart semantics : if syscall was already / can't be restarted) * upper short word optionally containing the syscall num - needed by likes of tracehooks etc This patch only changes how orig_r8 is organised and nothing should change behaviourily. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Al Viro <viro@ZenIV.linux.org.uk>
2013-02-11 14:31:24 +00:00
ARC: pt_regs update #5: Use real ECR for pt_regs->event vs. synth values pt_regs->event was set with artificial values to identify the low level system event (syscall trap / breakpoint trap / exceptions / interrupts) With r8 saving out of the way, the full word can be used to save real ECR (Exception Cause Register) which helps idenify the event naturally, including additional info such as cause code, param. Only for Interrupts, where ECR is not applicable, do we resort to synthetic non ECR values. SAVE_ALL_TRAP/EXCEPTIONS can now be merged as they both use ECR with different runtime values. The ptrace helpers now use the sub-fields of ECR to distinguish the events (e.g. vector 0x25 is trap, param 0 is syscall...) The following benefits will follow: (1) This centralizes the location of where ECR is saved and will allow the cleanup of task->thread.cause_code ECR placeholder which is set in non-uniform way. Then ARC VM code can safely rely on it being there for purpose of finer grained VM_EXEC dcache flush (based on exec fault: I-TLB Miss) (2) Further, ECR being passed around from low level handlers as arg can be eliminated as it is part of standard reg-file in pt_regs Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-06-11 13:26:54 +00:00
/*
* To distinguish bet excp, syscall, irq
* For traps and exceptions, Exception Cause Register.
* ECR: <00> <VV> <CC> <PP>
* Last word used by Linux for extra state mgmt (syscall-restart)
* For interrupts, use artificial ECR values to note current prio-level
*/
ARC: [Review] Preparing to fix incorrect syscall restarts due to signals To avoid multiple syscall restarts (multiple signals) or no restart at all (sigreturn), we need just an extra bit of state "literally 1 bit" in struct pt_regs. orig_r8 is the best place to do this, however given the way it is encoded currently, we can't add anything simplistically. Current orig_r8: * syscalls -> 1 to NR_SYSCALLS * Exceptions -> NR_SYSCALLS + 1 * Break-point-> NR_SYSCALLS + 2 In new scheme it is a bit-field * lower short word contains the exact event type (and a new bit to represent restart semantics : if syscall was already / can't be restarted) * upper short word optionally containing the syscall num - needed by likes of tracehooks etc This patch only changes how orig_r8 is organised and nothing should change behaviourily. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Al Viro <viro@ZenIV.linux.org.uk>
2013-02-11 14:31:24 +00:00
union {
ARC: pt_regs update #5: Use real ECR for pt_regs->event vs. synth values pt_regs->event was set with artificial values to identify the low level system event (syscall trap / breakpoint trap / exceptions / interrupts) With r8 saving out of the way, the full word can be used to save real ECR (Exception Cause Register) which helps idenify the event naturally, including additional info such as cause code, param. Only for Interrupts, where ECR is not applicable, do we resort to synthetic non ECR values. SAVE_ALL_TRAP/EXCEPTIONS can now be merged as they both use ECR with different runtime values. The ptrace helpers now use the sub-fields of ECR to distinguish the events (e.g. vector 0x25 is trap, param 0 is syscall...) The following benefits will follow: (1) This centralizes the location of where ECR is saved and will allow the cleanup of task->thread.cause_code ECR placeholder which is set in non-uniform way. Then ARC VM code can safely rely on it being there for purpose of finer grained VM_EXEC dcache flush (based on exec fault: I-TLB Miss) (2) Further, ECR being passed around from low level handlers as arg can be eliminated as it is part of standard reg-file in pt_regs Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-06-11 13:26:54 +00:00
struct {
ARC: [Review] Preparing to fix incorrect syscall restarts due to signals To avoid multiple syscall restarts (multiple signals) or no restart at all (sigreturn), we need just an extra bit of state "literally 1 bit" in struct pt_regs. orig_r8 is the best place to do this, however given the way it is encoded currently, we can't add anything simplistically. Current orig_r8: * syscalls -> 1 to NR_SYSCALLS * Exceptions -> NR_SYSCALLS + 1 * Break-point-> NR_SYSCALLS + 2 In new scheme it is a bit-field * lower short word contains the exact event type (and a new bit to represent restart semantics : if syscall was already / can't be restarted) * upper short word optionally containing the syscall num - needed by likes of tracehooks etc This patch only changes how orig_r8 is organised and nothing should change behaviourily. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Al Viro <viro@ZenIV.linux.org.uk>
2013-02-11 14:31:24 +00:00
#ifdef CONFIG_CPU_BIG_ENDIAN
ARC: pt_regs update #5: Use real ECR for pt_regs->event vs. synth values pt_regs->event was set with artificial values to identify the low level system event (syscall trap / breakpoint trap / exceptions / interrupts) With r8 saving out of the way, the full word can be used to save real ECR (Exception Cause Register) which helps idenify the event naturally, including additional info such as cause code, param. Only for Interrupts, where ECR is not applicable, do we resort to synthetic non ECR values. SAVE_ALL_TRAP/EXCEPTIONS can now be merged as they both use ECR with different runtime values. The ptrace helpers now use the sub-fields of ECR to distinguish the events (e.g. vector 0x25 is trap, param 0 is syscall...) The following benefits will follow: (1) This centralizes the location of where ECR is saved and will allow the cleanup of task->thread.cause_code ECR placeholder which is set in non-uniform way. Then ARC VM code can safely rely on it being there for purpose of finer grained VM_EXEC dcache flush (based on exec fault: I-TLB Miss) (2) Further, ECR being passed around from low level handlers as arg can be eliminated as it is part of standard reg-file in pt_regs Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-06-11 13:26:54 +00:00
unsigned long state:8, ecr_vec:8,
ecr_cause:8, ecr_param:8;
ARC: [Review] Preparing to fix incorrect syscall restarts due to signals To avoid multiple syscall restarts (multiple signals) or no restart at all (sigreturn), we need just an extra bit of state "literally 1 bit" in struct pt_regs. orig_r8 is the best place to do this, however given the way it is encoded currently, we can't add anything simplistically. Current orig_r8: * syscalls -> 1 to NR_SYSCALLS * Exceptions -> NR_SYSCALLS + 1 * Break-point-> NR_SYSCALLS + 2 In new scheme it is a bit-field * lower short word contains the exact event type (and a new bit to represent restart semantics : if syscall was already / can't be restarted) * upper short word optionally containing the syscall num - needed by likes of tracehooks etc This patch only changes how orig_r8 is organised and nothing should change behaviourily. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Al Viro <viro@ZenIV.linux.org.uk>
2013-02-11 14:31:24 +00:00
#else
ARC: pt_regs update #5: Use real ECR for pt_regs->event vs. synth values pt_regs->event was set with artificial values to identify the low level system event (syscall trap / breakpoint trap / exceptions / interrupts) With r8 saving out of the way, the full word can be used to save real ECR (Exception Cause Register) which helps idenify the event naturally, including additional info such as cause code, param. Only for Interrupts, where ECR is not applicable, do we resort to synthetic non ECR values. SAVE_ALL_TRAP/EXCEPTIONS can now be merged as they both use ECR with different runtime values. The ptrace helpers now use the sub-fields of ECR to distinguish the events (e.g. vector 0x25 is trap, param 0 is syscall...) The following benefits will follow: (1) This centralizes the location of where ECR is saved and will allow the cleanup of task->thread.cause_code ECR placeholder which is set in non-uniform way. Then ARC VM code can safely rely on it being there for purpose of finer grained VM_EXEC dcache flush (based on exec fault: I-TLB Miss) (2) Further, ECR being passed around from low level handlers as arg can be eliminated as it is part of standard reg-file in pt_regs Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-06-11 13:26:54 +00:00
unsigned long ecr_param:8, ecr_cause:8,
ecr_vec:8, state:8;
ARC: [Review] Preparing to fix incorrect syscall restarts due to signals To avoid multiple syscall restarts (multiple signals) or no restart at all (sigreturn), we need just an extra bit of state "literally 1 bit" in struct pt_regs. orig_r8 is the best place to do this, however given the way it is encoded currently, we can't add anything simplistically. Current orig_r8: * syscalls -> 1 to NR_SYSCALLS * Exceptions -> NR_SYSCALLS + 1 * Break-point-> NR_SYSCALLS + 2 In new scheme it is a bit-field * lower short word contains the exact event type (and a new bit to represent restart semantics : if syscall was already / can't be restarted) * upper short word optionally containing the syscall num - needed by likes of tracehooks etc This patch only changes how orig_r8 is organised and nothing should change behaviourily. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Al Viro <viro@ZenIV.linux.org.uk>
2013-02-11 14:31:24 +00:00
#endif
ARC: pt_regs update #5: Use real ECR for pt_regs->event vs. synth values pt_regs->event was set with artificial values to identify the low level system event (syscall trap / breakpoint trap / exceptions / interrupts) With r8 saving out of the way, the full word can be used to save real ECR (Exception Cause Register) which helps idenify the event naturally, including additional info such as cause code, param. Only for Interrupts, where ECR is not applicable, do we resort to synthetic non ECR values. SAVE_ALL_TRAP/EXCEPTIONS can now be merged as they both use ECR with different runtime values. The ptrace helpers now use the sub-fields of ECR to distinguish the events (e.g. vector 0x25 is trap, param 0 is syscall...) The following benefits will follow: (1) This centralizes the location of where ECR is saved and will allow the cleanup of task->thread.cause_code ECR placeholder which is set in non-uniform way. Then ARC VM code can safely rely on it being there for purpose of finer grained VM_EXEC dcache flush (based on exec fault: I-TLB Miss) (2) Further, ECR being passed around from low level handlers as arg can be eliminated as it is part of standard reg-file in pt_regs Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-06-11 13:26:54 +00:00
};
unsigned long event;
ARC: [Review] Preparing to fix incorrect syscall restarts due to signals To avoid multiple syscall restarts (multiple signals) or no restart at all (sigreturn), we need just an extra bit of state "literally 1 bit" in struct pt_regs. orig_r8 is the best place to do this, however given the way it is encoded currently, we can't add anything simplistically. Current orig_r8: * syscalls -> 1 to NR_SYSCALLS * Exceptions -> NR_SYSCALLS + 1 * Break-point-> NR_SYSCALLS + 2 In new scheme it is a bit-field * lower short word contains the exact event type (and a new bit to represent restart semantics : if syscall was already / can't be restarted) * upper short word optionally containing the syscall num - needed by likes of tracehooks etc This patch only changes how orig_r8 is organised and nothing should change behaviourily. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Al Viro <viro@ZenIV.linux.org.uk>
2013-02-11 14:31:24 +00:00
};
ARC: pt_regs update #4: r25 saved/restored unconditionally (This is a VERY IMP change for low level interrupt/exception handling) ----------------------------------------------------------------------- WHAT ----------------------------------------------------------------------- * User 25 now saved in pt_regs->user_r25 (vs. tsk->thread_info.user_r25) * This allows Low level interrupt code to unconditionally save r25 (vs. the prev version which would only do it for U->K transition). Ofcourse for nested interrupts, only the pt_regs->user_r25 of bottom-most frame is useful. * simplifies the interrupt prologue/epilogue * Needed for ARCv2 ISA code and done here to keep design similar with ARCompact event handling ----------------------------------------------------------------------- WHY ------------------------------------------------------------------------- With CONFIG_ARC_CURR_IN_REG, r25 is used to cache "current" task pointer in kernel mode. So when entering kernel mode from User Mode - user r25 is specially safe-kept (it being a callee reg is NOT part of pt_regs which are saved by default on each interrupt/trap/exception) - r25 loaded with current task pointer. Further, if interrupt was taken in kernel mode, this is skipped since we know that r25 already has valid "current" pointer. With 2 level of interrupts in ARCompact ISA, detecting this is difficult but still possible, since we could be in kernel mode but r25 not already saved (in fact the stack itself might not have been switched). A. User mode B. L1 IRQ taken C. L2 IRQ taken (while on 1st line of L1 ISR) So in #C, although in kernel mode, r25 not saved (infact SP not switched at all) Given that ARcompact has manual stack switching, we could use a bit of trickey - The low level code would make sure that SP is only set to kernel mode value at the very end (after saving r25). So a non kernel mode SP, even if in kernel mode, meant r25 was NOT saved. The same paradigm won't work in ARCv2 ISA since SP is auto-switched so it's setting can't be delayed/constrained. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-05-28 08:20:41 +00:00
long user_r25;
ARC: Fundamental ARCH data-types/defines * L1_CACHE_SHIFT * PAGE_SIZE, PAGE_OFFSET * struct pt_regs, struct user_regs_struct * struct thread_struct, cpu_relax(), task_pt_regs(), start_thread(), ... * struct thread_info, THREAD_SIZE, INIT_THREAD_INFO(), TIF_*, ... * BUG() * ELF_* * Elf_* To disallow user-space visibility into some of the core kernel data-types such as struct pt_regs, #ifdef __KERNEL__ which also makes the UAPI header spit (further patch in the series) to NOT export it to asm/uapi/ptrace.h Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Jonas Bonn <jonas.bonn@gmail.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-01-18 09:42:17 +00:00
};
/* Callee saved registers - need to be saved only when you are scheduled out */
struct callee_regs {
ARC: Code cosmetics (Nothing semantical) * reduce editor lines taken by pt_regs * ARCompact ISA specific part of TLB Miss handlers clubbed together * cleanup some comments Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-07-10 06:10:27 +00:00
long r25, r24, r23, r22, r21, r20, r19, r18, r17, r16, r15, r14, r13;
ARC: Fundamental ARCH data-types/defines * L1_CACHE_SHIFT * PAGE_SIZE, PAGE_OFFSET * struct pt_regs, struct user_regs_struct * struct thread_struct, cpu_relax(), task_pt_regs(), start_thread(), ... * struct thread_info, THREAD_SIZE, INIT_THREAD_INFO(), TIF_*, ... * BUG() * ELF_* * Elf_* To disallow user-space visibility into some of the core kernel data-types such as struct pt_regs, #ifdef __KERNEL__ which also makes the UAPI header spit (further patch in the series) to NOT export it to asm/uapi/ptrace.h Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Jonas Bonn <jonas.bonn@gmail.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-01-18 09:42:17 +00:00
};
#define instruction_pointer(regs) ((regs)->ret)
#define profile_pc(regs) instruction_pointer(regs)
/* return 1 if user mode or 0 if kernel mode */
#define user_mode(regs) (regs->status32 & STATUS_U_MASK)
#define user_stack_pointer(regs)\
({ unsigned int sp; \
if (user_mode(regs)) \
sp = (regs)->sp;\
else \
sp = -1; \
sp; \
})
ARC: Syscall support (no-legacy-syscall ABI) This includes support for generic clone/for/vfork/execve Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Al Viro <viro@ZenIV.linux.org.uk> Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-01-18 09:42:18 +00:00
ARC: Unaligned access emulation ARC700 doesn't natively support unaligned access, but can be emulated -Unaligned Access Exception -Disassembly at the Fault address to find the exact insn (long/short) Also per Arnd's comment, we runtime control it using 2 sysctl knobs: * SYSCTL_ARCH_UNALIGN_ALLOW: Runtime enable/disble * SYSCTL_ARCH_UNALIGN_NO_WARN: Warn on each emulation attempt Originally contributed by Tim Yao <tim.yao@amlogic.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Tim Yao <tim.yao@amlogic.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-01-23 11:00:36 +00:00
/* return 1 if PC in delay slot */
#define delay_mode(regs) ((regs->status32 & STATUS_DE_MASK) == STATUS_DE_MASK)
ARC: pt_regs update #5: Use real ECR for pt_regs->event vs. synth values pt_regs->event was set with artificial values to identify the low level system event (syscall trap / breakpoint trap / exceptions / interrupts) With r8 saving out of the way, the full word can be used to save real ECR (Exception Cause Register) which helps idenify the event naturally, including additional info such as cause code, param. Only for Interrupts, where ECR is not applicable, do we resort to synthetic non ECR values. SAVE_ALL_TRAP/EXCEPTIONS can now be merged as they both use ECR with different runtime values. The ptrace helpers now use the sub-fields of ECR to distinguish the events (e.g. vector 0x25 is trap, param 0 is syscall...) The following benefits will follow: (1) This centralizes the location of where ECR is saved and will allow the cleanup of task->thread.cause_code ECR placeholder which is set in non-uniform way. Then ARC VM code can safely rely on it being there for purpose of finer grained VM_EXEC dcache flush (based on exec fault: I-TLB Miss) (2) Further, ECR being passed around from low level handlers as arg can be eliminated as it is part of standard reg-file in pt_regs Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-06-11 13:26:54 +00:00
#define in_syscall(regs) ((regs->ecr_vec == ECR_V_TRAP) && !regs->ecr_param)
#define in_brkpt_trap(regs) ((regs->ecr_vec == ECR_V_TRAP) && regs->ecr_param)
ARC: Syscall support (no-legacy-syscall ABI) This includes support for generic clone/for/vfork/execve Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Al Viro <viro@ZenIV.linux.org.uk> Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-01-18 09:42:18 +00:00
ARC: pt_regs update #5: Use real ECR for pt_regs->event vs. synth values pt_regs->event was set with artificial values to identify the low level system event (syscall trap / breakpoint trap / exceptions / interrupts) With r8 saving out of the way, the full word can be used to save real ECR (Exception Cause Register) which helps idenify the event naturally, including additional info such as cause code, param. Only for Interrupts, where ECR is not applicable, do we resort to synthetic non ECR values. SAVE_ALL_TRAP/EXCEPTIONS can now be merged as they both use ECR with different runtime values. The ptrace helpers now use the sub-fields of ECR to distinguish the events (e.g. vector 0x25 is trap, param 0 is syscall...) The following benefits will follow: (1) This centralizes the location of where ECR is saved and will allow the cleanup of task->thread.cause_code ECR placeholder which is set in non-uniform way. Then ARC VM code can safely rely on it being there for purpose of finer grained VM_EXEC dcache flush (based on exec fault: I-TLB Miss) (2) Further, ECR being passed around from low level handlers as arg can be eliminated as it is part of standard reg-file in pt_regs Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-06-11 13:26:54 +00:00
#define STATE_SCALL_RESTARTED 0x01
#define syscall_wont_restart(reg) (reg->state |= STATE_SCALL_RESTARTED)
#define syscall_restartable(reg) !(reg->state & STATE_SCALL_RESTARTED)
ARC: [Review] Prevent incorrect syscall restarts Per Al Viro's "signals for dummies" https://lkml.org/lkml/2012/12/6/366 there are 3 golden rules for (not) restarting syscalls: " What we need to guarantee is * restarts do not happen on signals caught in interrupts or exceptions * restarts do not happen on signals caught in sigreturn() * restart should happen only once, even if we get through do_signal() many times." ARC Port already handled #1, this patch fixes #2 and #3. We use the additional state in pt_regs->orig_r8 to ckh if restarting has already been done once. Thanks to Al Viro for spotting this. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Al Viro <viro@ZenIV.linux.org.uk>
2013-01-18 09:42:19 +00:00
ARC: Process-creation/scheduling/idle-loop Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de>
2013-01-18 09:42:18 +00:00
#define current_pt_regs() \
({ \
/* open-coded current_thread_info() */ \
register unsigned long sp asm ("sp"); \
unsigned long pg_start = (sp & ~(THREAD_SIZE - 1)); \
ARC: pt_regs update #1: Align pt_regs end with end of kernel stack page Historically, pt_regs would end at offset of 1 word from end of stack page. ----------------- -> START of page (task->stack) | | | thread_info | ----------------- | | ^ ~ ~ | ~ ~ | | | | | | <---- pt_regs used to END here ----------------- | 1 word GUTTER | ----------------- -> End of page (START of kernel stack) This required special "one-off" considerations in low level code. The root cause is very likely assumption of "empty" SP by the original ARC kernel hackers, despite ARC700 always been "full" SP. So finally RIP one word gutter ! Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-05-28 04:04:45 +00:00
(struct pt_regs *)(pg_start + THREAD_SIZE) - 1; \
ARC: Process-creation/scheduling/idle-loop Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Thomas Gleixner <tglx@linutronix.de>
2013-01-18 09:42:18 +00:00
})
ARC: kprobes support Origin port done by Rajeshwar Ranga Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com>
2013-01-22 11:33:59 +00:00
static inline long regs_return_value(struct pt_regs *regs)
{
return regs->r0;
}
ARC: Fundamental ARCH data-types/defines * L1_CACHE_SHIFT * PAGE_SIZE, PAGE_OFFSET * struct pt_regs, struct user_regs_struct * struct thread_struct, cpu_relax(), task_pt_regs(), start_thread(), ... * struct thread_info, THREAD_SIZE, INIT_THREAD_INFO(), TIF_*, ... * BUG() * ELF_* * Elf_* To disallow user-space visibility into some of the core kernel data-types such as struct pt_regs, #ifdef __KERNEL__ which also makes the UAPI header spit (further patch in the series) to NOT export it to asm/uapi/ptrace.h Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Jonas Bonn <jonas.bonn@gmail.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-01-18 09:42:17 +00:00
#endif /* !__ASSEMBLY__ */
#endif /* __ASM_PTRACE_H */
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