diff options
| author | Niklas Schnelle <schnelle@linux.ibm.com> | 2023-09-28 16:31:37 +0200 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2023-10-02 08:43:00 +0200 |
| commit | c76c067e488ccd55734c3e750799caf2c5956db6 (patch) | |
| tree | c4489302a1c2a119afcba4b54535cb4d8c65cbee /Documentation/admin-guide/kernel-parameters.txt | |
| parent | b6f888709a155b4e748aded93afc9fa43aaa28dd (diff) | |
s390/pci: Use dma-iommu layer
While s390 already has a standard IOMMU driver and previous changes have
added I/O TLB flushing operations this driver is currently only used for
user-space PCI access such as vfio-pci. For the DMA API s390 instead
utilizes its own implementation in arch/s390/pci/pci_dma.c which drives
the same hardware and shares some code but requires a complex and
fragile hand over between DMA API and IOMMU API use of a device and
despite code sharing still leads to significant duplication and
maintenance effort. Let's utilize the common code DMAP API
implementation from drivers/iommu/dma-iommu.c instead allowing us to
get rid of arch/s390/pci/pci_dma.c.
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Link: https://lore.kernel.org/r/20230928-dma_iommu-v13-3-9e5fc4dacc36@linux.ibm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'Documentation/admin-guide/kernel-parameters.txt')
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 0a1731a0f0ef..14f56c448edc 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -2220,7 +2220,7 @@ forcing Dual Address Cycle for PCI cards supporting greater than 32-bit addressing. - iommu.strict= [ARM64, X86] Configure TLB invalidation behaviour + iommu.strict= [ARM64, X86, S390] Configure TLB invalidation behaviour Format: { "0" | "1" } 0 - Lazy mode. Request that DMA unmap operations use deferred @@ -5611,9 +5611,10 @@ s390_iommu= [HW,S390] Set s390 IOTLB flushing mode strict - With strict flushing every unmap operation will result in - an IOTLB flush. Default is lazy flushing before reuse, - which is faster. + With strict flushing every unmap operation will result + in an IOTLB flush. Default is lazy flushing before + reuse, which is faster. Deprecated, equivalent to + iommu.strict=1. s390_iommu_aperture= [KNL,S390] Specifies the size of the per device DMA address space |