diff options
| author | Ravi Bangoria <ravi.bangoria@linux.ibm.com> | 2020-05-14 16:47:35 +0530 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2020-05-19 00:11:05 +1000 |
| commit | 6b424efa119d5ea06b15ff240dddc3b4b9f9cdfb (patch) | |
| tree | 4ea2eb0294720b9913b767cabe2f93b498f26e9d /arch/powerpc/kernel/ptrace | |
| parent | 303e6a9ddcdc168e92253c78cdb4bbe1e10d78b3 (diff) | |
powerpc/watchpoint: Use loop for thread_struct->ptrace_bps
ptrace_bps is already an array of size HBP_NUM_MAX. But we use
hardcoded index 0 while fetching/updating it. Convert such code
to loop over array.
ptrace interface to use multiple watchpoint remains same. eg:
two PPC_PTRACE_SETHWDEBUG calls will create two watchpoint if
underneath hw supports it.
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Michael Neuling <mikey@neuling.org>
Link: https://lore.kernel.org/r/20200514111741.97993-11-ravi.bangoria@linux.ibm.com
Diffstat (limited to 'arch/powerpc/kernel/ptrace')
| -rw-r--r-- | arch/powerpc/kernel/ptrace/ptrace-noadv.c | 28 |
1 files changed, 21 insertions, 7 deletions
diff --git a/arch/powerpc/kernel/ptrace/ptrace-noadv.c b/arch/powerpc/kernel/ptrace/ptrace-noadv.c index 0dbb35392dd2..08cb8c1b504c 100644 --- a/arch/powerpc/kernel/ptrace/ptrace-noadv.c +++ b/arch/powerpc/kernel/ptrace/ptrace-noadv.c @@ -168,6 +168,19 @@ int ptrace_set_debugreg(struct task_struct *task, unsigned long addr, unsigned l return 0; } +#ifdef CONFIG_HAVE_HW_BREAKPOINT +static int find_empty_ptrace_bp(struct thread_struct *thread) +{ + int i; + + for (i = 0; i < nr_wp_slots(); i++) { + if (!thread->ptrace_bps[i]) + return i; + } + return -1; +} +#endif + static int find_empty_hw_brk(struct thread_struct *thread) { int i; @@ -217,8 +230,9 @@ long ppc_set_hwdebug(struct task_struct *child, struct ppc_hw_breakpoint *bp_inf len = 1; else return -EINVAL; - bp = thread->ptrace_bps[0]; - if (bp) + + i = find_empty_ptrace_bp(thread); + if (i < 0) return -ENOSPC; /* Create a new breakpoint request if one doesn't exist already */ @@ -228,13 +242,13 @@ long ppc_set_hwdebug(struct task_struct *child, struct ppc_hw_breakpoint *bp_inf arch_bp_generic_fields(brk.type, &attr.bp_type); bp = register_user_hw_breakpoint(&attr, ptrace_triggered, NULL, child); - thread->ptrace_bps[0] = bp; + thread->ptrace_bps[i] = bp; if (IS_ERR(bp)) { - thread->ptrace_bps[0] = NULL; + thread->ptrace_bps[i] = NULL; return PTR_ERR(bp); } - return 1; + return i + 1; #endif /* CONFIG_HAVE_HW_BREAKPOINT */ if (bp_info->addr_mode != PPC_BREAKPOINT_MODE_EXACT) @@ -263,10 +277,10 @@ long ppc_del_hwdebug(struct task_struct *child, long data) return -EINVAL; #ifdef CONFIG_HAVE_HW_BREAKPOINT - bp = thread->ptrace_bps[0]; + bp = thread->ptrace_bps[data - 1]; if (bp) { unregister_hw_breakpoint(bp); - thread->ptrace_bps[0] = NULL; + thread->ptrace_bps[data - 1] = NULL; } else { ret = -ENOENT; } |