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authorSrikant Patnaik2015-01-11 12:28:04 +0530
committerSrikant Patnaik2015-01-11 12:28:04 +0530
commit871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch)
tree8718f573808810c2a1e8cb8fb6ac469093ca2784 /arch/x86/include/asm/debugreg.h
parent9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff)
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Moved, renamed, and deleted files
The original directory structure was scattered and unorganized. Changes are basically to make it look like kernel structure.
Diffstat (limited to 'arch/x86/include/asm/debugreg.h')
-rw-r--r--arch/x86/include/asm/debugreg.h195
1 files changed, 195 insertions, 0 deletions
diff --git a/arch/x86/include/asm/debugreg.h b/arch/x86/include/asm/debugreg.h
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+++ b/arch/x86/include/asm/debugreg.h
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+#ifndef _ASM_X86_DEBUGREG_H
+#define _ASM_X86_DEBUGREG_H
+
+
+/* Indicate the register numbers for a number of the specific
+ debug registers. Registers 0-3 contain the addresses we wish to trap on */
+#define DR_FIRSTADDR 0 /* u_debugreg[DR_FIRSTADDR] */
+#define DR_LASTADDR 3 /* u_debugreg[DR_LASTADDR] */
+
+#define DR_STATUS 6 /* u_debugreg[DR_STATUS] */
+#define DR_CONTROL 7 /* u_debugreg[DR_CONTROL] */
+
+/* Define a few things for the status register. We can use this to determine
+ which debugging register was responsible for the trap. The other bits
+ are either reserved or not of interest to us. */
+
+/* Define reserved bits in DR6 which are always set to 1 */
+#define DR6_RESERVED (0xFFFF0FF0)
+
+#define DR_TRAP0 (0x1) /* db0 */
+#define DR_TRAP1 (0x2) /* db1 */
+#define DR_TRAP2 (0x4) /* db2 */
+#define DR_TRAP3 (0x8) /* db3 */
+#define DR_TRAP_BITS (DR_TRAP0|DR_TRAP1|DR_TRAP2|DR_TRAP3)
+
+#define DR_STEP (0x4000) /* single-step */
+#define DR_SWITCH (0x8000) /* task switch */
+
+/* Now define a bunch of things for manipulating the control register.
+ The top two bytes of the control register consist of 4 fields of 4
+ bits - each field corresponds to one of the four debug registers,
+ and indicates what types of access we trap on, and how large the data
+ field is that we are looking at */
+
+#define DR_CONTROL_SHIFT 16 /* Skip this many bits in ctl register */
+#define DR_CONTROL_SIZE 4 /* 4 control bits per register */
+
+#define DR_RW_EXECUTE (0x0) /* Settings for the access types to trap on */
+#define DR_RW_WRITE (0x1)
+#define DR_RW_READ (0x3)
+
+#define DR_LEN_1 (0x0) /* Settings for data length to trap on */
+#define DR_LEN_2 (0x4)
+#define DR_LEN_4 (0xC)
+#define DR_LEN_8 (0x8)
+
+/* The low byte to the control register determine which registers are
+ enabled. There are 4 fields of two bits. One bit is "local", meaning
+ that the processor will reset the bit after a task switch and the other
+ is global meaning that we have to explicitly reset the bit. With linux,
+ you can use either one, since we explicitly zero the register when we enter
+ kernel mode. */
+
+#define DR_LOCAL_ENABLE_SHIFT 0 /* Extra shift to the local enable bit */
+#define DR_GLOBAL_ENABLE_SHIFT 1 /* Extra shift to the global enable bit */
+#define DR_LOCAL_ENABLE (0x1) /* Local enable for reg 0 */
+#define DR_GLOBAL_ENABLE (0x2) /* Global enable for reg 0 */
+#define DR_ENABLE_SIZE 2 /* 2 enable bits per register */
+
+#define DR_LOCAL_ENABLE_MASK (0x55) /* Set local bits for all 4 regs */
+#define DR_GLOBAL_ENABLE_MASK (0xAA) /* Set global bits for all 4 regs */
+
+/* The second byte to the control register has a few special things.
+ We can slow the instruction pipeline for instructions coming via the
+ gdt or the ldt if we want to. I am not sure why this is an advantage */
+
+#ifdef __i386__
+#define DR_CONTROL_RESERVED (0xFC00) /* Reserved by Intel */
+#else
+#define DR_CONTROL_RESERVED (0xFFFFFFFF0000FC00UL) /* Reserved */
+#endif
+
+#define DR_LOCAL_SLOWDOWN (0x100) /* Local slow the pipeline */
+#define DR_GLOBAL_SLOWDOWN (0x200) /* Global slow the pipeline */
+
+/*
+ * HW breakpoint additions
+ */
+#ifdef __KERNEL__
+
+#include <linux/bug.h>
+
+DECLARE_PER_CPU(unsigned long, cpu_dr7);
+
+#ifndef CONFIG_PARAVIRT
+/*
+ * These special macros can be used to get or set a debugging register
+ */
+#define get_debugreg(var, register) \
+ (var) = native_get_debugreg(register)
+#define set_debugreg(value, register) \
+ native_set_debugreg(register, value)
+#endif
+
+static inline unsigned long native_get_debugreg(int regno)
+{
+ unsigned long val = 0; /* Damn you, gcc! */
+
+ switch (regno) {
+ case 0:
+ asm("mov %%db0, %0" :"=r" (val));
+ break;
+ case 1:
+ asm("mov %%db1, %0" :"=r" (val));
+ break;
+ case 2:
+ asm("mov %%db2, %0" :"=r" (val));
+ break;
+ case 3:
+ asm("mov %%db3, %0" :"=r" (val));
+ break;
+ case 6:
+ asm("mov %%db6, %0" :"=r" (val));
+ break;
+ case 7:
+ asm("mov %%db7, %0" :"=r" (val));
+ break;
+ default:
+ BUG();
+ }
+ return val;
+}
+
+static inline void native_set_debugreg(int regno, unsigned long value)
+{
+ switch (regno) {
+ case 0:
+ asm("mov %0, %%db0" ::"r" (value));
+ break;
+ case 1:
+ asm("mov %0, %%db1" ::"r" (value));
+ break;
+ case 2:
+ asm("mov %0, %%db2" ::"r" (value));
+ break;
+ case 3:
+ asm("mov %0, %%db3" ::"r" (value));
+ break;
+ case 6:
+ asm("mov %0, %%db6" ::"r" (value));
+ break;
+ case 7:
+ asm("mov %0, %%db7" ::"r" (value));
+ break;
+ default:
+ BUG();
+ }
+}
+
+static inline void hw_breakpoint_disable(void)
+{
+ /* Zero the control register for HW Breakpoint */
+ set_debugreg(0UL, 7);
+
+ /* Zero-out the individual HW breakpoint address registers */
+ set_debugreg(0UL, 0);
+ set_debugreg(0UL, 1);
+ set_debugreg(0UL, 2);
+ set_debugreg(0UL, 3);
+}
+
+static inline int hw_breakpoint_active(void)
+{
+ return __this_cpu_read(cpu_dr7) & DR_GLOBAL_ENABLE_MASK;
+}
+
+extern void aout_dump_debugregs(struct user *dump);
+
+extern void hw_breakpoint_restore(void);
+
+#ifdef CONFIG_X86_64
+DECLARE_PER_CPU(int, debug_stack_usage);
+static inline void debug_stack_usage_inc(void)
+{
+ __get_cpu_var(debug_stack_usage)++;
+}
+static inline void debug_stack_usage_dec(void)
+{
+ __get_cpu_var(debug_stack_usage)--;
+}
+int is_debug_stack(unsigned long addr);
+void debug_stack_set_zero(void);
+void debug_stack_reset(void);
+#else /* !X86_64 */
+static inline int is_debug_stack(unsigned long addr) { return 0; }
+static inline void debug_stack_set_zero(void) { }
+static inline void debug_stack_reset(void) { }
+static inline void debug_stack_usage_inc(void) { }
+static inline void debug_stack_usage_dec(void) { }
+#endif /* X86_64 */
+
+
+#endif /* __KERNEL__ */
+
+#endif /* _ASM_X86_DEBUGREG_H */