releases/5.0.4/swiotlb-introduce-swiotlb_max_mapping_size.patch

   1 From abe420bfae528c92bd8cc5ecb62dc95672b1fd6f Mon Sep 17 00:00:00 2001
   2 From: Joerg Roedel <jroedel@suse.de>
   3 Date: Thu, 7 Feb 2019 12:59:13 +0100
   4 Subject: swiotlb: Introduce swiotlb_max_mapping_size()
   5
   6 From: Joerg Roedel <jroedel@suse.de>
   7
   8 commit abe420bfae528c92bd8cc5ecb62dc95672b1fd6f upstream.
   9
  10 The function returns the maximum size that can be remapped
  11 by the SWIOTLB implementation. This function will be later
  12 exposed to users through the DMA-API.
  13
  14 Cc: stable@vger.kernel.org
  15 Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
  16 Reviewed-by: Christoph Hellwig <hch@lst.de>
  17 Signed-off-by: Joerg Roedel <jroedel@suse.de>
  18 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
  19 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  20
  21 ---
  22  include/linux/swiotlb.h |    5 +++++
  23  kernel/dma/swiotlb.c    |    5 +++++
  24  2 files changed, 10 insertions(+)
  25
  26 --- a/include/linux/swiotlb.h
  27 +++ b/include/linux/swiotlb.h
  28 @@ -76,6 +76,7 @@ bool swiotlb_map(struct device *dev, phy
  29                 size_t size, enum dma_data_direction dir, unsigned long attrs);
  30  void __init swiotlb_exit(void);
  31  unsigned int swiotlb_max_segment(void);
  32 +size_t swiotlb_max_mapping_size(struct device *dev);
  33  #else
  34  #define swiotlb_force SWIOTLB_NO_FORCE
  35  static inline bool is_swiotlb_buffer(phys_addr_t paddr)
  36 @@ -95,6 +96,10 @@ static inline unsigned int swiotlb_max_s
  37  {
  38         return 0;
  39  }
  40 +static inline size_t swiotlb_max_mapping_size(struct device *dev)
  41 +{
  42 +       return SIZE_MAX;
  43 +}
  44  #endif /* CONFIG_SWIOTLB */
  45
  46  extern void swiotlb_print_info(void);
  47 --- a/kernel/dma/swiotlb.c
  48 +++ b/kernel/dma/swiotlb.c
  49 @@ -662,3 +662,8 @@ swiotlb_dma_supported(struct device *hwd
  50  {
  51         return __phys_to_dma(hwdev, io_tlb_end - 1) <= mask;
  52  }
  53 +
  54 +size_t swiotlb_max_mapping_size(struct device *dev)
  55 +{
  56 +       return ((size_t)1 << IO_TLB_SHIFT) * IO_TLB_SEGSIZE;
  57 +}