[PATCH RFCv2 05/18] uprobes: Add nbytes argument to uprobe_write_opcode

[Jiri Olsa <jolsa@kernel.org>]

Adding nbytes argument to uprobe_write_opcode as preparation
for writing whole instructions in following changes.

Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 include/linux/uprobes.h |  4 ++--
 kernel/events/uprobes.c | 14 +++++++-------
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h
index 732de4b796ce..8867b6a168b2 100644
--- a/include/linux/uprobes.h
+++ b/include/linux/uprobes.h
@@ -185,7 +185,7 @@ struct uprobes_state {
 	struct xol_area		*xol_area;
 };
 
-typedef int (*uprobe_write_verify_t)(struct page *page, unsigned long vaddr, uprobe_opcode_t *opcode);
+typedef int (*uprobe_write_verify_t)(struct page *page, unsigned long vaddr, uprobe_opcode_t *opcode, int nbytes);
 
 extern void __init uprobes_init(void);
 extern int set_swbp(struct arch_uprobe *aup, struct mm_struct *mm, unsigned long vaddr);
@@ -196,7 +196,7 @@ extern unsigned long uprobe_get_swbp_addr(struct pt_regs *regs);
 extern unsigned long uprobe_get_trap_addr(struct pt_regs *regs);
 extern int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long vaddr, uprobe_opcode_t);
 extern int uprobe_write(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long vaddr,
-			uprobe_opcode_t *opcode, uprobe_write_verify_t verify);
+			uprobe_opcode_t *insn, int nbytes, uprobe_write_verify_t verify);
 extern struct uprobe *uprobe_register(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, struct uprobe_consumer *uc);
 extern int uprobe_apply(struct uprobe *uprobe, struct uprobe_consumer *uc, bool);
 extern void uprobe_unregister_nosync(struct uprobe *uprobe, struct uprobe_consumer *uc);
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 50560b307522..ad5879fc2d26 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -264,7 +264,7 @@ static void uprobe_copy_to_page(struct page *page, unsigned long vaddr, const vo
 	kunmap_atomic(kaddr);
 }
 
-static int verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t *new_opcode)
+static int verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t *new_opcode, int nbytes)
 {
 	uprobe_opcode_t old_opcode;
 	bool is_swbp;
@@ -473,12 +473,12 @@ static int update_ref_ctr(struct uprobe *uprobe, struct mm_struct *mm,
 int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm,
 			unsigned long vaddr, uprobe_opcode_t opcode)
 {
-	return uprobe_write(auprobe, mm, vaddr, &opcode, verify_opcode);
+	return uprobe_write(auprobe, mm, vaddr, &opcode, UPROBE_SWBP_INSN_SIZE, verify_opcode);
 }
 
 int uprobe_write(struct arch_uprobe *auprobe, struct mm_struct *mm,
-		 unsigned long vaddr, uprobe_opcode_t *opcode,
-		 uprobe_write_verify_t verify)
+		 unsigned long vaddr, uprobe_opcode_t *insn,
+		 int nbytes, uprobe_write_verify_t verify)
 {
 	struct page *old_page, *new_page;
 	struct vm_area_struct *vma;
@@ -486,7 +486,7 @@ int uprobe_write(struct arch_uprobe *auprobe, struct mm_struct *mm,
 	bool orig_page_huge = false;
 	unsigned int gup_flags = FOLL_FORCE;
 
-	is_register = is_swbp_insn(opcode);
+	is_register = is_swbp_insn(insn);
 
 retry:
 	if (is_register)
@@ -496,7 +496,7 @@ int uprobe_write(struct arch_uprobe *auprobe, struct mm_struct *mm,
 	if (IS_ERR(old_page))
 		return PTR_ERR(old_page);
 
-	ret = verify(old_page, vaddr, opcode);
+	ret = verify(old_page, vaddr, insn, nbytes);
 	if (ret <= 0)
 		goto put_old;
 
@@ -521,7 +521,7 @@ int uprobe_write(struct arch_uprobe *auprobe, struct mm_struct *mm,
 
 	__SetPageUptodate(new_page);
 	copy_highpage(new_page, old_page);
-	uprobe_copy_to_page(new_page, vaddr, opcode, UPROBE_SWBP_INSN_SIZE);
+	uprobe_copy_to_page(new_page, vaddr, insn, nbytes);
 
 	if (!is_register) {
 		struct page *orig_page;
-- 
2.48.1