user/sven/linux.git/kernel/dma/mapping.c, branch v5.7

dma-mapping: Fix dma_pgprot() for unencrypted coherent pages

2020-03-17T10:52:58Z

When dma_mmap_coherent() sets up a mapping to unencrypted coherent memory under SEV encryption and sometimes under SME encryption, it will actually set up an encrypted mapping rather than an unencrypted, causing devices that DMAs from that memory to read encrypted contents. Fix this. When force_dma_unencrypted() returns true, the linear kernel map of the coherent pages have had the encryption bit explicitly cleared and the page content is unencrypted. Make sure that any additional PTEs we set up to these pages also have the encryption bit cleared by having dma_pgprot() return a protection with the encryption bit cleared in this case. Signed-off-by: Thomas Hellstrom Signed-off-by: Borislav Petkov Reviewed-by: Christoph Hellwig Acked-by: Tom Lendacky Link: https://lkml.kernel.org/r/20200304114527.3636-3-thomas_os@shipmail.org

dma-direct: provide mmap and get_sgtable method overrides

2019-11-11T09:52:15Z

For dma-direct we know that the DMA address is an encoding of the physical address that we can trivially decode. Use that fact to provide implementations that do not need the arch_dma_coherent_to_pfn architecture hook. Note that we still can only support mmap of non-coherent memory only if the architecture provides a way to set an uncached bit in the page tables. This must be true for architectures that use the generic remap helpers, but other architectures can also manually select it. Signed-off-by: Christoph Hellwig Reviewed-by: Max Filippov

Merge tag 'powerpc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

2019-09-20T18:48:06Z

Pull powerpc updates from Michael Ellerman: "This is a bit late, partly due to me travelling, and partly due to a power outage knocking out some of my test systems *while* I was travelling. - Initial support for running on a system with an Ultravisor, which is software that runs below the hypervisor and protects guests against some attacks by the hypervisor. - Support for building the kernel to run as a "Secure Virtual Machine", ie. as a guest capable of running on a system with an Ultravisor. - Some changes to our DMA code on bare metal, to allow devices with medium sized DMA masks (> 32 && < 59 bits) to use more than 2GB of DMA space. - Support for firmware assisted crash dumps on bare metal (powernv). - Two series fixing bugs in and refactoring our PCI EEH code. - A large series refactoring our exception entry code to use gas macros, both to make it more readable and also enable some future optimisations. As well as many cleanups and other minor features & fixups. Thanks to: Adam Zerella, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anshuman Khandual, Balbir Singh, Benjamin Herrenschmidt, Cédric Le Goater, Christophe JAILLET, Christophe Leroy, Christopher M. Riedl, Christoph Hellwig, Claudio Carvalho, Daniel Axtens, David Gibson, David Hildenbrand, Desnes A. Nunes do Rosario, Ganesh Goudar, Gautham R. Shenoy, Greg Kurz, Guerney Hunt, Gustavo Romero, Halil Pasic, Hari Bathini, Joakim Tjernlund, Jonathan Neuschafer, Jordan Niethe, Leonardo Bras, Lianbo Jiang, Madhavan Srinivasan, Mahesh Salgaonkar, Mahesh Salgaonkar, Masahiro Yamada, Maxiwell S. Garcia, Michael Anderson, Nathan Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Qian Cai, Ram Pai, Ravi Bangoria, Reza Arbab, Ryan Grimm, Sam Bobroff, Santosh Sivaraj, Segher Boessenkool, Sukadev Bhattiprolu, Thiago Bauermann, Thiago Jung Bauermann, Thomas Gleixner, Tom Lendacky, Vasant Hegde" * tag 'powerpc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (264 commits) powerpc/mm/mce: Keep irqs disabled during lockless page table walk powerpc: Use ftrace_graph_ret_addr() when unwinding powerpc/ftrace: Enable HAVE_FUNCTION_GRAPH_RET_ADDR_PTR ftrace: Look up the address of return_to_handler() using helpers powerpc: dump kernel log before carrying out fadump or kdump docs: powerpc: Add missing documentation reference powerpc/xmon: Fix output of XIVE IPI powerpc/xmon: Improve output of XIVE interrupts powerpc/mm/radix: remove useless kernel messages powerpc/fadump: support holes in kernel boot memory area powerpc/fadump: remove RMA_START and RMA_END macros powerpc/fadump: update documentation about option to release opalcore powerpc/fadump: consider f/w load area powerpc/opalcore: provide an option to invalidate /sys/firmware/opal/core file powerpc/opalcore: export /sys/firmware/opal/core for analysing opal crashes powerpc/fadump: update documentation about CONFIG_PRESERVE_FA_DUMP powerpc/fadump: add support to preserve crash data on FADUMP disabled kernel powerpc/fadump: improve how crashed kernel's memory is reserved powerpc/fadump: consider reserved ranges while releasing memory powerpc/fadump: make crash memory ranges array allocation generic ...

dma-mapping: provide a better default ->get_required_mask

2019-09-04T09:13:19Z

Most dma_map_ops instances are IOMMUs that work perfectly fine in 32-bits of IOVA space, and the generic direct mapping code already provides its own routines that is intelligent based on the amount of memory actually present. Wire up the dma-direct routine for the ARM direct mapping code as well, and otherwise default to the constant 32-bit mask. This way we only need to override it for the occasional odd IOMMU that requires 64-bit IOVA support, or IOMMU drivers that are more efficient if they can fall back to the direct mapping. Signed-off-by: Christoph Hellwig

dma-mapping: remove CONFIG_ARCH_NO_COHERENT_DMA_MMAP

2019-09-04T09:13:18Z

CONFIG_ARCH_NO_COHERENT_DMA_MMAP is now functionally identical to !CONFIG_MMU, so remove the separate symbol. The only difference is that arm did not set it for !CONFIG_MMU, but arm uses a separate dma mapping implementation including its own mmap method, which is handled by moving the CONFIG_MMU check in dma_can_mmap so that is only applies to the dma-direct case, just as the other ifdefs for it. Signed-off-by: Christoph Hellwig Acked-by: Geert Uytterhoeven # m68k

dma-mapping: add a dma_can_mmap helper

2019-09-04T09:13:18Z

Add a helper to check if DMA allocations for a specific device can be mapped to userspace using dma_mmap_*. Signed-off-by: Christoph Hellwig

dma-mapping: explicitly wire up ->mmap and ->get_sgtable

2019-09-04T09:13:18Z

While the default ->mmap and ->get_sgtable implementations work for the majority of our dma_map_ops impementations they are inherently safe for others that don't use the page allocator or CMA and/or use their own way of remapping not covered by the common code. So remove the defaults if these methods are not wired up, but instead wire up the default implementations for all safe instances. Fixes: e1c7e324539a ("dma-mapping: always provide the dma_map_ops based implementation") Signed-off-by: Christoph Hellwig

dma-mapping: move the dma_get_sgtable API comments from arm to common code

2019-09-04T09:13:17Z

The comments are spot on and should be near the central API, not just near a single implementation. Signed-off-by: Christoph Hellwig

dma-mapping: introduce dma_get_merge_boundary()

2019-09-03T06:33:01Z

This patch adds a new DMA API "dma_get_merge_boundary". This function returns the DMA merge boundary if the DMA layer can merge the segments. This patch also adds the implementation for a new dma_map_ops pointer. Signed-off-by: Yoshihiro Shimoda Reviewed-by: Simon Horman Signed-off-by: Christoph Hellwig

dma-mapping: remove arch_dma_mmap_pgprot

2019-08-29T14:43:22Z

arch_dma_mmap_pgprot is used for two things: 1) to override the "normal" uncached page attributes for mapping memory coherent to devices that can't snoop the CPU caches 2) to provide the special DMA_ATTR_WRITE_COMBINE semantics on older arm systems and some mips platforms Replace one with the pgprot_dmacoherent macro that is already provided by arm and much simpler to use, and lift the DMA_ATTR_WRITE_COMBINE handling to common code with an explicit arch opt-in. Signed-off-by: Christoph Hellwig Acked-by: Geert Uytterhoeven # m68k Acked-by: Paul Burton # mips