[Xen-devel] [PATCH 0/9] Use vm_insert_range and vm_insert_range_buggy

[Souptick Joarder <jrdr.linux@xxxxxxxxx>]

Previouly drivers have their own way of mapping range of
kernel pages/memory into user vma and this was done by
invoking vm_insert_page() within a loop.

As this pattern is common across different drivers, it can
be generalized by creating new functions and use it across
the drivers.

vm_insert_range() is the API which could be used to mapped
kernel memory/pages in drivers which has considered vm_pgoff

vm_insert_range_buggy() is the API which could be used to map
range of kernel memory/pages in drivers which has not considered
vm_pgoff. vm_pgoff is passed default as 0 for those drivers.

We _could_ then at a later "fix" these drivers which are using
vm_insert_range_buggy() to behave according to the normal vm_pgoff
offsetting simply by removing the _buggy suffix on the function
name and if that causes regressions, it gives us an easy way to revert.

There is an existing bug in [7/9], where user passed length is not
verified against object_count. For any value of length > object_count
it will end up overrun page array which could lead to a potential bug.
This is fixed as part of these conversion.

Souptick Joarder (9):
  mm: Introduce new vm_insert_range and vm_insert_range_buggy API
  arch/arm/mm/dma-mapping.c: Convert to use vm_insert_range
  drivers/firewire/core-iso.c: Convert to use vm_insert_range_buggy
  drm/rockchip/rockchip_drm_gem.c: Convert to use vm_insert_range
  drm/xen/xen_drm_front_gem.c: Convert to use vm_insert_range
  iommu/dma-iommu.c: Convert to use vm_insert_range
  videobuf2/videobuf2-dma-sg.c: Convert to use vm_insert_range_buggy
  xen/gntdev.c: Convert to use vm_insert_range
  xen/privcmd-buf.c: Convert to use vm_insert_range_buggy

 arch/arm/mm/dma-mapping.c                         | 22 ++----
 drivers/firewire/core-iso.c                       | 15 +----
 drivers/gpu/drm/rockchip/rockchip_drm_gem.c       | 17 +----
 drivers/gpu/drm/xen/xen_drm_front_gem.c           | 18 ++---
 drivers/iommu/dma-iommu.c                         | 12 +---
 drivers/media/common/videobuf2/videobuf2-dma-sg.c | 22 ++----
 drivers/xen/gntdev.c                              | 16 ++---
 drivers/xen/privcmd-buf.c                         |  8 +--
 include/linux/mm.h                                |  4 ++
 mm/memory.c                                       | 81 +++++++++++++++++++++++
 mm/nommu.c                                        | 14 ++++
 11 files changed, 129 insertions(+), 100 deletions(-)

-- 
1.9.1


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