linux-toradex.git/include/linux/swiotlb.h, branch v5.19-rc3

swiotlb: remove swiotlb_init_with_tbl and swiotlb_init_late_with_tbl

2022-04-18T05:21:14+00:00

No users left.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Konrad Rzeszutek Wilk 
Tested-by: Boris Ostrovsky

swiotlb: provide swiotlb_init variants that remap the buffer

2022-04-18T05:21:13+00:00

To shared more code between swiotlb and xen-swiotlb, offer a
swiotlb_init_remap interface and add a remap callback to
swiotlb_init_late that will allow Xen to remap the buffer without
duplicating much of the logic.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Konrad Rzeszutek Wilk 
Tested-by: Boris Ostrovsky

swiotlb: pass a gfp_mask argument to swiotlb_init_late

2022-04-18T05:21:12+00:00

Let the caller chose a zone to allocate from.  This will be used
later on by the xen-swiotlb initialization on arm.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Anshuman Khandual 
Reviewed-by: Konrad Rzeszutek Wilk 
Tested-by: Boris Ostrovsky

swiotlb: add a SWIOTLB_ANY flag to lift the low memory restriction

2022-04-18T05:21:12+00:00

Power SVM wants to allocate a swiotlb buffer that is not restricted to
low memory for the trusted hypervisor scheme.  Consolidate the support
for this into the swiotlb_init interface by adding a new flag.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Konrad Rzeszutek Wilk 
Tested-by: Boris Ostrovsky

swiotlb: make the swiotlb_init interface more useful

2022-04-18T05:21:11+00:00

Pass a boolean flag to indicate if swiotlb needs to be enabled based on
the addressing needs, and replace the verbose argument with a set of
flags, including one to force enable bounce buffering.

Note that this patch removes the possibility to force xen-swiotlb use
with the swiotlb=force parameter on the command line on x86 (arm and
arm64 never supported that), but this interface will be restored shortly.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Konrad Rzeszutek Wilk 
Tested-by: Boris Ostrovsky

swiotlb: rename swiotlb_late_init_with_default_size

2022-04-18T05:21:09+00:00

swiotlb_late_init_with_default_size is an overly verbose name that
doesn't even catch what the function is doing, given that the size is
not just a default but the actual requested size.

Rename it to swiotlb_init_late.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Anshuman Khandual 
Reviewed-by: Konrad Rzeszutek Wilk 
Tested-by: Boris Ostrovsky

swiotlb: simplify swiotlb_max_segment

2022-04-18T05:21:09+00:00

Remove the bogus Xen override that was usually larger than the actual
size and just calculate the value on demand.  Note that
swiotlb_max_segment still doesn't make sense as an interface and should
eventually be removed.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Anshuman Khandual 
Reviewed-by: Konrad Rzeszutek Wilk 
Tested-by: Boris Ostrovsky

swiotlb: Add swiotlb bounce buffer remap function for HV IVM

2021-12-20T18:01:09+00:00

In Isolation VM with AMD SEV, bounce buffer needs to be accessed via
extra address space which is above shared_gpa_boundary (E.G 39 bit
address line) reported by Hyper-V CPUID ISOLATION_CONFIG. The access
physical address will be original physical address + shared_gpa_boundary.
The shared_gpa_boundary in the AMD SEV SNP spec is called virtual top of
memory(vTOM). Memory addresses below vTOM are automatically treated as
private while memory above vTOM is treated as shared.

Expose swiotlb_unencrypted_base for platforms to set unencrypted
memory base offset and platform calls swiotlb_update_mem_attributes()
to remap swiotlb mem to unencrypted address space. memremap() can
not be called in the early stage and so put remapping code into
swiotlb_update_mem_attributes(). Store remap address and use it to copy
data from/to swiotlb bounce buffer.

Signed-off-by: Tianyu Lan 
Acked-by: Christoph Hellwig 
Reviewed-by: Michael Kelley 
Link: https://lore.kernel.org/r/20211213071407.314309-2-ltykernel@gmail.com
Signed-off-by: Wei Liu

swiotlb: Support aligned swiotlb buffers

2021-09-29T10:50:34+00:00

Add an argument to swiotlb_tbl_map_single that specifies the desired
alignment of the allocated buffer. This is used by dma-iommu to ensure
the buffer is aligned to the iova granule size when using swiotlb with
untrusted sub-granule mappings. This addresses an issue where adjacent
slots could be exposed to the untrusted device if IO_TLB_SIZE < iova
granule < PAGE_SIZE.

Signed-off-by: David Stevens 
Reviewed-by: Christoph Hellwig 
Link: https://lore.kernel.org/r/20210929023300.335969-7-stevensd@google.com
Signed-off-by: Joerg Roedel

swiotlb: Convert io_default_tlb_mem to static allocation

2021-07-24T00:14:43+00:00

Since commit 69031f500865 ("swiotlb: Set dev->dma_io_tlb_mem to the
swiotlb pool used"), 'struct device' may hold a copy of the global
'io_default_tlb_mem' pointer if the device is using swiotlb for DMA. A
subsequent call to swiotlb_exit() will therefore leave dangling pointers
behind in these device structures, resulting in KASAN splats such as:

  |  BUG: KASAN: use-after-free in __iommu_dma_unmap_swiotlb+0x64/0xb0
  |  Read of size 8 at addr ffff8881d7830000 by task swapper/0/0
  |
  |  CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.12.0-rc3-debug #1
  |  Hardware name: HP HP Desktop M01-F1xxx/87D6, BIOS F.12 12/17/2020
  |  Call Trace:
  |   
  |   dump_stack+0x9c/0xcf
  |   print_address_description.constprop.0+0x18/0x130
  |   kasan_report.cold+0x7f/0x111
  |   __iommu_dma_unmap_swiotlb+0x64/0xb0
  |   nvme_pci_complete_rq+0x73/0x130
  |   blk_complete_reqs+0x6f/0x80
  |   __do_softirq+0xfc/0x3be

Convert 'io_default_tlb_mem' to a static structure, so that the
per-device pointers remain valid after swiotlb_exit() has been invoked.
All users are updated to reference the static structure directly, using
the 'nslabs' field to determine whether swiotlb has been initialised.
The 'slots' array is still allocated dynamically and referenced via a
pointer rather than a flexible array member.

Cc: Claire Chang 
Cc: Christoph Hellwig 
Cc: Robin Murphy 
Cc: Konrad Rzeszutek Wilk 
Fixes: 69031f500865 ("swiotlb: Set dev->dma_io_tlb_mem to the swiotlb pool used")
Reported-by: Nathan Chancellor 
Tested-by: Nathan Chancellor 
Tested-by: Claire Chang 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Will Deacon 
Signed-off-by: Konrad Rzeszutek Wilk