[PATCH v13 16/20] IB/mlx4, arm64: untag user pointers in mlx4_get_umem_mr
From: Andrey Konovalov <hidden>
Date: 2019-03-20 14:52:44
Also in:
bpf, linux-arch, linux-kselftest, linux-media, linux-mm, lkml
Subsystem:
infiniband subsystem, mellanox mlx4 ib driver, the rest · Maintainers:
Jason Gunthorpe, Leon Romanovsky, Yishai Hadas, Linus Torvalds
This patch is a part of a series that extends arm64 kernel ABI to allow to pass tagged user pointers (with the top byte set to something else other than 0x00) as syscall arguments. mlx4_get_umem_mr() uses provided user pointers for vma lookups, which can only by done with untagged pointers. Untag user pointers in this function. Signed-off-by: Andrey Konovalov <redacted> --- drivers/infiniband/hw/mlx4/mr.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/infiniband/hw/mlx4/mr.c b/drivers/infiniband/hw/mlx4/mr.c
index 395379a480cb..9a35ed2c6a6f 100644
--- a/drivers/infiniband/hw/mlx4/mr.c
+++ b/drivers/infiniband/hw/mlx4/mr.c@@ -378,6 +378,7 @@ static struct ib_umem *mlx4_get_umem_mr(struct ib_udata *udata, u64 start, * again */ if (!ib_access_writable(access_flags)) { + unsigned long untagged_start = untagged_addr(start); struct vm_area_struct *vma; down_read(¤t->mm->mmap_sem);
@@ -386,9 +387,9 @@ static struct ib_umem *mlx4_get_umem_mr(struct ib_udata *udata, u64 start, * cover the memory, but for now it requires a single vma to * entirely cover the MR to support RO mappings. */ - vma = find_vma(current->mm, start); - if (vma && vma->vm_end >= start + length && - vma->vm_start <= start) { + vma = find_vma(current->mm, untagged_start); + if (vma && vma->vm_end >= untagged_start + length && + vma->vm_start <= untagged_start) { if (vma->vm_flags & VM_WRITE) access_flags |= IB_ACCESS_LOCAL_WRITE; } else {
--
2.21.0.225.g810b269d1ac-goog