[PATCH] ppc64: Add ptrace data breakpoint support

Add hardware data breakpoint support.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

5 files changed, 39 insertions, 0 deletions

diff --git a/include/asm-ppc64/hvcall.h b/include/asm-ppc64/hvcall.h
index 4f668a4baff0..ab7c3cf24888 100644
--- a/include/asm-ppc64/hvcall.h
+++ b/include/asm-ppc64/hvcall.h
@@ -56,6 +56,11 @@
 #define H_PP1                   (1UL<<(63-62))
 #define H_PP2                   (1UL<<(63-63))
 
+/* DABRX flags */
+#define H_DABRX_HYPERVISOR      (1UL<<(63-61))
+#define H_DABRX_KERNEL          (1UL<<(63-62))
+#define H_DABRX_USER            (1UL<<(63-63))
+
 /* pSeries hypervisor opcodes */
 #define H_REMOVE                0x04
 #define H_ENTER                 0x08
@@ -101,6 +106,7 @@
 #define H_VIO_SIGNAL            0x104
 #define H_SEND_CRQ              0x108
 #define H_COPY_RDMA             0x110
+#define H_SET_XDABR             0x134
 #define H_STUFF_TCE             0x138
 #define H_PUT_TCE_INDIRECT      0x13C
 #define H_VTERM_PARTNER_INFO    0x150
diff --git a/include/asm-ppc64/plpar_wrappers.h b/include/asm-ppc64/plpar_wrappers.h
index f4a5fb7d67c7..72dd2449ee76 100644
--- a/include/asm-ppc64/plpar_wrappers.h
+++ b/include/asm-ppc64/plpar_wrappers.h
@@ -107,5 +107,14 @@ static inline long plpar_put_term_char(unsigned long termno,
                                   lbuf[1]);
 }
 
+static inline long plpar_set_xdabr(unsigned long address, unsigned long flags)
+{
+        return plpar_hcall_norets(H_SET_XDABR, address, flags);
+}
+
+static inline long plpar_set_dabr(unsigned long val)
+{
+        return plpar_hcall_norets(H_SET_DABR, val);
+}
 
 #endif /* _PPC64_PLPAR_WRAPPERS_H */
diff --git a/include/asm-ppc64/processor.h b/include/asm-ppc64/processor.h
index 8bd7aa959385..4146189006e3 100644
--- a/include/asm-ppc64/processor.h
+++ b/include/asm-ppc64/processor.h
@@ -433,6 +433,7 @@ struct thread_struct {
         unsigned long   start_tb;       /* Start purr when proc switched in */
         unsigned long   accum_tb;       /* Total accumilated purr for process */
         unsigned long   vdso_base;      /* base of the vDSO library */
+        unsigned long   dabr;           /* Data address breakpoint register */
 #ifdef CONFIG_ALTIVEC
         /* Complete AltiVec register set */
         vector128       vr[32] __attribute((aligned(16)));
diff --git a/include/asm-ppc64/ptrace-common.h b/include/asm-ppc64/ptrace-common.h
index bd0f84c27bd0..b1babb729673 100644
--- a/include/asm-ppc64/ptrace-common.h
+++ b/include/asm-ppc64/ptrace-common.h
@@ -13,6 +13,7 @@
 #define _PPC64_PTRACE_COMMON_H
 
 #include <linux/config.h>
+#include <asm/system.h>
 
 /*
  * Set of msr bits that gdb can change on behalf of a process.
@@ -141,4 +142,23 @@ static inline int set_vrregs(struct task_struct *task,
 }
 #endif
 
+static inline int ptrace_set_debugreg(struct task_struct *task,
+                                      unsigned long addr, unsigned long data)
+{
+        /* We only support one DABR and no IABRS at the moment */
+        if (addr > 0)
+                return -EINVAL;
+
+        /* The bottom 3 bits are flags */
+        if ((data & ~0x7UL) >= TASK_SIZE)
+                return -EIO;
+
+        /* Ensure translation is on */
+        if (data && !(data & DABR_TRANSLATION))
+                return -EIO;
+
+        task->thread.dabr = data;
+        return 0;
+}
+
 #endif /* _PPC64_PTRACE_COMMON_H */
diff --git a/include/asm-ppc64/system.h b/include/asm-ppc64/system.h
index c0396428cc3c..375015c62f20 100644
--- a/include/asm-ppc64/system.h
+++ b/include/asm-ppc64/system.h
@@ -101,6 +101,9 @@ static inline int debugger_dabr_match(struct pt_regs *regs) { return 0; }
 static inline int debugger_fault_handler(struct pt_regs *regs) { return 0; }
 #endif
 
+extern int set_dabr(unsigned long dabr);
+extern void _exception(int signr, struct pt_regs *regs, int code,
+                       unsigned long addr);
 extern int fix_alignment(struct pt_regs *regs);
 extern void bad_page_fault(struct pt_regs *regs, unsigned long address,
                            int sig);