diff options
author | Oleg Nesterov <oleg@redhat.com> | 2013-03-24 21:58:04 +0400 |
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committer | Oleg Nesterov <oleg@redhat.com> | 2013-04-04 15:57:05 +0400 |
commit | 5669ccee21d87622f30a724b3fe0d04ec5b0afae (patch) | |
tree | b8eda48d364795c9ccb07c9df9f29fbf9fa7199e /kernel/events | |
parent | 98763a1bb1515f8a8d7f1d9ae42604e19872364b (diff) | |
download | linux-5669ccee21d87622f30a724b3fe0d04ec5b0afae.tar.xz |
uprobes: Introduce copy_to_page()
Extract the kmap_atomic/memcpy/kunmap_atomic code from
xol_get_insn_slot() into the new simple helper, copy_to_page().
It will have more users soon.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Anton Arapov <anton@redhat.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Diffstat (limited to 'kernel/events')
-rw-r--r-- | kernel/events/uprobes.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 093866547fe3..b8255eaca190 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -194,6 +194,13 @@ static void copy_from_page(struct page *page, unsigned long vaddr, void *dst, in kunmap_atomic(kaddr); } +static void copy_to_page(struct page *page, unsigned long vaddr, const void *src, int len) +{ + void *kaddr = kmap_atomic(page); + memcpy(kaddr + (vaddr & ~PAGE_MASK), src, len); + kunmap_atomic(kaddr); +} + static int verify_opcode(struct page *page, unsigned long vaddr, uprobe_opcode_t *new_opcode) { uprobe_opcode_t old_opcode; @@ -1227,9 +1234,7 @@ static unsigned long xol_take_insn_slot(struct xol_area *area) static unsigned long xol_get_insn_slot(struct uprobe *uprobe) { struct xol_area *area; - unsigned long offset; unsigned long xol_vaddr; - void *vaddr; area = get_xol_area(); if (!area) @@ -1240,10 +1245,7 @@ static unsigned long xol_get_insn_slot(struct uprobe *uprobe) return 0; /* Initialize the slot */ - offset = xol_vaddr & ~PAGE_MASK; - vaddr = kmap_atomic(area->page); - memcpy(vaddr + offset, uprobe->arch.insn, MAX_UINSN_BYTES); - kunmap_atomic(vaddr); + copy_to_page(area->page, xol_vaddr, uprobe->arch.insn, MAX_UINSN_BYTES); /* * We probably need flush_icache_user_range() but it needs vma. * This should work on supported architectures too. |