[PATCH v2 3/6] uprobes: get rid of enum uprobe_filter_ctx in uprobe filter callbacks

[Andrii Nakryiko <andrii@kernel.org>]

It serves no purpose beyond adding unnecessray argument passed to the
filter callback. Just get rid of it, no one is actually using it.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
---
 include/linux/uprobes.h     | 10 +---------
 kernel/events/uprobes.c     | 18 +++++++-----------
 kernel/trace/bpf_trace.c    |  3 +--
 kernel/trace/trace_uprobe.c |  9 +++------
 4 files changed, 12 insertions(+), 28 deletions(-)

diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h
index f50df1fa93e7..63ae2ade3487 100644
--- a/include/linux/uprobes.h
+++ b/include/linux/uprobes.h
@@ -28,20 +28,12 @@ struct page;
 
 #define MAX_URETPROBE_DEPTH		64
 
-enum uprobe_filter_ctx {
-	UPROBE_FILTER_REGISTER,
-	UPROBE_FILTER_UNREGISTER,
-	UPROBE_FILTER_MMAP,
-};
-
 struct uprobe_consumer {
 	int (*handler)(struct uprobe_consumer *self, struct pt_regs *regs);
 	int (*ret_handler)(struct uprobe_consumer *self,
 				unsigned long func,
 				struct pt_regs *regs);
-	bool (*filter)(struct uprobe_consumer *self,
-				enum uprobe_filter_ctx ctx,
-				struct mm_struct *mm);
+	bool (*filter)(struct uprobe_consumer *self, struct mm_struct *mm);
 
 	struct uprobe_consumer *next;
 };
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 11c97f178dbf..9b31235bc177 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -920,21 +920,19 @@ static int prepare_uprobe(struct uprobe *uprobe, struct file *file,
 	return ret;
 }
 
-static inline bool consumer_filter(struct uprobe_consumer *uc,
-				   enum uprobe_filter_ctx ctx, struct mm_struct *mm)
+static inline bool consumer_filter(struct uprobe_consumer *uc, struct mm_struct *mm)
 {
-	return !uc->filter || uc->filter(uc, ctx, mm);
+	return !uc->filter || uc->filter(uc, mm);
 }
 
-static bool filter_chain(struct uprobe *uprobe,
-			 enum uprobe_filter_ctx ctx, struct mm_struct *mm)
+static bool filter_chain(struct uprobe *uprobe, struct mm_struct *mm)
 {
 	struct uprobe_consumer *uc;
 	bool ret = false;
 
 	down_read(&uprobe->consumer_rwsem);
 	for (uc = uprobe->consumers; uc; uc = uc->next) {
-		ret = consumer_filter(uc, ctx, mm);
+		ret = consumer_filter(uc, mm);
 		if (ret)
 			break;
 	}
@@ -1101,12 +1099,10 @@ register_for_each_vma(struct uprobe *uprobe, struct uprobe_consumer *new)
 
 		if (is_register) {
 			/* consult only the "caller", new consumer. */
-			if (consumer_filter(new,
-					UPROBE_FILTER_REGISTER, mm))
+			if (consumer_filter(new, mm))
 				err = install_breakpoint(uprobe, mm, vma, info->vaddr);
 		} else if (test_bit(MMF_HAS_UPROBES, &mm->flags)) {
-			if (!filter_chain(uprobe,
-					UPROBE_FILTER_UNREGISTER, mm))
+			if (!filter_chain(uprobe, mm))
 				err |= remove_breakpoint(uprobe, mm, info->vaddr);
 		}
 
@@ -1389,7 +1385,7 @@ int uprobe_mmap(struct vm_area_struct *vma)
 	 */
 	list_for_each_entry_safe(uprobe, u, &tmp_list, pending_list) {
 		if (!fatal_signal_pending(current) &&
-		    filter_chain(uprobe, UPROBE_FILTER_MMAP, vma->vm_mm)) {
+		    filter_chain(uprobe, vma->vm_mm)) {
 			unsigned long vaddr = offset_to_vaddr(vma, uprobe->offset);
 			install_breakpoint(uprobe, vma->vm_mm, vma, vaddr);
 		}
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 4e391daafa64..73c570b5988b 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -3320,8 +3320,7 @@ static int uprobe_prog_run(struct bpf_uprobe *uprobe,
 }
 
 static bool
-uprobe_multi_link_filter(struct uprobe_consumer *con, enum uprobe_filter_ctx ctx,
-			 struct mm_struct *mm)
+uprobe_multi_link_filter(struct uprobe_consumer *con, struct mm_struct *mm)
 {
 	struct bpf_uprobe *uprobe;
 
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index 52e76a73fa7c..7eb79e0a5352 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -1078,9 +1078,7 @@ print_uprobe_event(struct trace_iterator *iter, int flags, struct trace_event *e
 	return trace_handle_return(s);
 }
 
-typedef bool (*filter_func_t)(struct uprobe_consumer *self,
-				enum uprobe_filter_ctx ctx,
-				struct mm_struct *mm);
+typedef bool (*filter_func_t)(struct uprobe_consumer *self, struct mm_struct *mm);
 
 static int trace_uprobe_enable(struct trace_uprobe *tu, filter_func_t filter)
 {
@@ -1339,8 +1337,7 @@ static int uprobe_perf_open(struct trace_event_call *call,
 	return err;
 }
 
-static bool uprobe_perf_filter(struct uprobe_consumer *uc,
-				enum uprobe_filter_ctx ctx, struct mm_struct *mm)
+static bool uprobe_perf_filter(struct uprobe_consumer *uc, struct mm_struct *mm)
 {
 	struct trace_uprobe_filter *filter;
 	struct trace_uprobe *tu;
@@ -1426,7 +1423,7 @@ static void __uprobe_perf_func(struct trace_uprobe *tu,
 static int uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs,
 			    struct uprobe_cpu_buffer **ucbp)
 {
-	if (!uprobe_perf_filter(&tu->consumer, 0, current->mm))
+	if (!uprobe_perf_filter(&tu->consumer, current->mm))
 		return UPROBE_HANDLER_REMOVE;
 
 	if (!is_ret_probe(tu))
-- 
2.43.5