Merge tag 'dma-mapping-6.6-2023-08-29' of git://git.infradead.org/users/hch/dma-mapping

Pull dma-maping updates from Christoph Hellwig:

 - allow dynamic sizing of the swiotlb buffer, to cater for secure
   virtualization workloads that require all I/O to be bounce buffered
   (Petr Tesarik)

 - move a declaration to a header (Arnd Bergmann)

 - check for memory region overlap in dma-contiguous (Binglei Wang)

 - remove the somewhat dangerous runtime swiotlb-xen enablement and
   unexport is_swiotlb_active (Christoph Hellwig, Juergen Gross)

 - per-node CMA improvements (Yajun Deng)

* tag 'dma-mapping-6.6-2023-08-29' of git://git.infradead.org/users/hch/dma-mapping:
  swiotlb: optimize get_max_slots()
  swiotlb: move slot allocation explanation comment where it belongs
  swiotlb: search the software IO TLB only if the device makes use of it
  swiotlb: allocate a new memory pool when existing pools are full
  swiotlb: determine potential physical address limit
  swiotlb: if swiotlb is full, fall back to a transient memory pool
  swiotlb: add a flag whether SWIOTLB is allowed to grow
  swiotlb: separate memory pool data from other allocator data
  swiotlb: add documentation and rename swiotlb_do_find_slots()
  swiotlb: make io_tlb_default_mem local to swiotlb.c
  swiotlb: bail out of swiotlb_init_late() if swiotlb is already allocated
  dma-contiguous: check for memory region overlap
  dma-contiguous: support numa CMA for specified node
  dma-contiguous: support per-numa CMA for all architectures
  dma-mapping: move arch_dma_set_mask() declaration to header
  swiotlb: unexport is_swiotlb_active
  x86: always initialize xen-swiotlb when xen-pcifront is enabling
  xen/pci: add flag for PCI passthrough being possible

1 files changed, 12 insertions, 1 deletions

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index e5d71ba4e6ae..93f646e0b4b5 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -696,7 +696,7 @@
 			kernel/dma/contiguous.c
 
 	cma_pernuma=nn[MG]
-			[ARM64,KNL,CMA]
+			[KNL,CMA]
 			Sets the size of kernel per-numa memory area for
 			contiguous memory allocations. A value of 0 disables
 			per-numa CMA altogether. And If this option is not
@@ -706,6 +706,17 @@
 			which is located in node nid, if the allocation fails,
 			they will fallback to the global default memory area.
 
+	numa_cma=<node>:nn[MG][,<node>:nn[MG]]
+			[KNL,CMA]
+			Sets the size of kernel numa memory area for
+			contiguous memory allocations. It will reserve CMA
+			area for the specified node.
+
+			With numa CMA enabled, DMA users on node nid will
+			first try to allocate buffer from the numa area
+			which is located in node nid, if the allocation fails,
+			they will fallback to the global default memory area.
+
 	cmo_free_hint=	[PPC] Format: { yes | no }
 			Specify whether pages are marked as being inactive
 			when they are freed.  This is used in CMO environments