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[kvm-unit-tests,v2,04/10] lib: Bundle debugreg.h from the kernel

Message ID 20200901085056.33391-5-r.bolshakov@yadro.com (mailing list archive)
State New, archived
Headers show
Series Add support for generic ELF cross-compiler | expand

Commit Message

Roman Bolshakov Sept. 1, 2020, 8:50 a.m. UTC
x86/vmx_tests.c depends on the kernel header and can't be compiled
otherwise on x86_64-elf gcc on macOS.

Cc: Jim Mattson <jmattson@google.com>
Cc: Peter Shier <pshier@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Cameron Esfahani <dirty@apple.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
---
 lib/x86/asm/debugreg.h | 81 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 81 insertions(+)
 create mode 100644 lib/x86/asm/debugreg.h
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Patch

diff --git a/lib/x86/asm/debugreg.h b/lib/x86/asm/debugreg.h
new file mode 100644
index 0000000..d95d080
--- /dev/null
+++ b/lib/x86/asm/debugreg.h
@@ -0,0 +1,81 @@ 
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+#ifndef _UAPI_ASM_X86_DEBUGREG_H
+#define _UAPI_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
+ */
+
+#endif /* _UAPI_ASM_X86_DEBUGREG_H */