diff options
| author | Rabin Vincent <rabin@rab.in> | 2013-10-07 14:39:53 -0400 |
|---|---|---|
| committer | David A. Long <dave.long@linaro.org> | 2013-10-14 01:36:56 -0400 |
| commit | ce819aeeba2ebd514ef5da18f6b1afc5f07e40b0 (patch) | |
| tree | 705ebb49a678e55d5035ee8cc406357f3522ea39 /kernel | |
| parent | b0dbfb680a87f1144c0c7bbe6280a96c1ebbec26 (diff) | |
uprobes: add arch write opcode hook
Allow arches to write the opcode with a custom function. ARM needs to
customize the swbp instruction depending on the condition code of the
instruction it replaces.
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: David A. Long <dave.long@linaro.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/events/uprobes.c | 21 |
1 files changed, 16 insertions, 5 deletions
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 9734a5f54805..cb01d827ae89 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -248,6 +248,12 @@ static int verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t * have fixed length instructions. */ +void __weak arch_uprobe_write_opcode(struct arch_uprobe *auprobe, void *vaddr, + uprobe_opcode_t opcode) +{ + memcpy(vaddr, &opcode, UPROBE_SWBP_INSN_SIZE); +} + /* * write_opcode - write the opcode at a given virtual address. * @mm: the probed process address space. @@ -260,11 +266,12 @@ static int verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t * For mm @mm, write the opcode at @vaddr. * Return 0 (success) or a negative errno. */ -static int write_opcode(struct mm_struct *mm, unsigned long vaddr, - uprobe_opcode_t opcode) +static int write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm, + unsigned long vaddr, uprobe_opcode_t opcode) { struct page *old_page, *new_page; struct vm_area_struct *vma; + void *vaddr_new; int ret; retry: @@ -285,7 +292,10 @@ retry: __SetPageUptodate(new_page); copy_highpage(new_page, old_page); - copy_to_page(new_page, vaddr, &opcode, UPROBE_SWBP_INSN_SIZE); + vaddr_new = kmap_atomic(new_page); + arch_uprobe_write_opcode(auprobe, vaddr_new + (vaddr & ~PAGE_MASK), + opcode); + kunmap_atomic(vaddr_new); ret = anon_vma_prepare(vma); if (ret) @@ -314,7 +324,7 @@ put_old: */ int __weak set_swbp(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long vaddr) { - return write_opcode(mm, vaddr, UPROBE_SWBP_INSN); + return write_opcode(auprobe, mm, vaddr, UPROBE_SWBP_INSN); } /** @@ -329,7 +339,8 @@ int __weak set_swbp(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned int __weak set_orig_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long vaddr) { - return write_opcode(mm, vaddr, *(uprobe_opcode_t *)auprobe->insn); + return write_opcode(auprobe, mm, vaddr, + *(uprobe_opcode_t *)auprobe->insn); } static int match_uprobe(struct uprobe *l, struct uprobe *r) |