Hi, This series centralizes swiotlb default-pool selection and sizing, and simplifies the initialization flags used to describe pool placement.
The first patch replaces the addressing-limit argument with initialization flags and introduces explicit policies for the different reasons a default pool may be needed. Architectures now report DMA addressing constraints with SWIOTLB_INIT_ADDRESSING_LIMIT, while the core selects the corresponding pool policy. The second patch moves the reduced sizing used when the pool is needed only for unaligned kmalloc bouncing from arm64 and RISC-V into the swiotlb core. The third patch centralizes swiotlb sizing for memory-encrypted systems. It moves the existing x86 guest-sizing policy into the core. Host memory encryption retains the normal pool size, and a shared default pool is not selected solely for guest memory encryption when a restricted DMA pool is present. The fourth patch removes SWIOTLB_ANY. Pool placement is derived directly from SWIOTLB_INIT_ADDRESSING_LIMIT: pools required for limited DMA addressing are allocated below the architecture's low address limit, while other pools may be allocated anywhere in directly mapped memory. Xen continues to request a pool explicitly with SWIOTLB_INIT_REMAP without imposing a low-address constraint. Changes from v5: https://lore.kernel.org/all/[email protected] * Collect Reviewed-by tags. * Drop the x86 crash changes * Add two new patches: "dma: swiotlb: Consolidate slab rounding" "dma: swiotlb: Rename swiotlb_size_or_default()" * Drop the swiotlb_default_size_changed() helper. * Simplify swiotlb_adjust_pool_size(). Changes from v4: https://lore.kernel.org/all/[email protected] * Collect Reviewed-by tags. * Add a new patch, "dma: swiotlb: Track whether the pool size was explicitly set". * Retain SWIOTLB_ANY usage for RISC-V until patch 6. * Rename SWIOTLB_INIT_FORCE_DISABLE to SWIOTLB_INIT_DEFAULT_OFF. Changes from v3: https://lore.kernel.org/all/[email protected] * Add a new patch, "dma: swiotlb: Add an overridable architecture pool opt-out". * Clarify the change in default behavior with the removal of SWIOTLB_ANY. Changes from v2: https://lore.kernel.org/all/[email protected] * Rebase to latest tree. * Drop SWIOTLB_ANY and derive that based on SWIOTLB_INIT_ADDRESSING_LIMIT * Add SWIOTLB_INIT_REMAP. v1: https://lore.kernel.org/all/[email protected] Cc: Robin Murphy <[email protected]> Cc: Marek Szyprowski <[email protected]> Cc: Jonathan Corbet <[email protected]> Cc: Shuah Khan <[email protected]> Cc: Randy Dunlap <[email protected]> Cc: Will Deacon <[email protected]> Cc: Mark Rutland <[email protected]> Cc: Marc Zyngier <[email protected]> Cc: Steven Price <[email protected]> Cc: Suzuki K Poulose <[email protected]> Cc: Catalin Marinas <[email protected]> Cc: Jiri Pirko <[email protected]> Cc: Jason Gunthorpe <[email protected]> Cc: Mostafa Saleh <[email protected]> Cc: Petr Tesarik <[email protected]> Cc: Alexey Kardashevskiy <[email protected]> Cc: Dan Williams <[email protected]> Cc: Xu Yilun <[email protected]> Cc: Madhavan Srinivasan <[email protected]> Cc: Michael Ellerman <[email protected]> Cc: Nicholas Piggin <[email protected]> Cc: "Christophe Leroy (CS GROUP)" <[email protected]> Cc: "Ritesh Harjani (IBM)" <[email protected]> Cc: Shrikanth Hegde <[email protected]> Cc: Alexander Gordeev <[email protected]> Cc: Gerald Schaefer <[email protected]> Cc: Heiko Carstens <[email protected]> Cc: Vasily Gorbik <[email protected]> Cc: Christian Borntraeger <[email protected]> Cc: Sven Schnelle <[email protected]> Cc: Stefano Stabellini <[email protected]> Cc: Russell King <[email protected]> Cc: Huacai Chen <[email protected]> Cc: WANG Xuerui <[email protected]> Cc: Thomas Bogendoerfer <[email protected]> Cc: Jiaxun Yang <[email protected]> Cc: Paul Walmsley <[email protected]> Cc: Palmer Dabbelt <[email protected]> Cc: Albert Ou <[email protected]> Cc: Alexandre Ghiti <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Dave Hansen <[email protected]> Cc: "H. Peter Anvin" <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Aneesh Kumar K.V (Arm) (8): dma: swiotlb: Rename swiotlb_size_or_default() dma: swiotlb: Consolidate slab rounding dma: swiotlb: Track whether the pool size was explicitly set dma: swiotlb: Centralize default pool policy selection dma: swiotlb: Centralize minimal pool sizing dma: swiotlb: Centralize memory-encryption pool sizing dma: swiotlb: Add an overridable architecture pool opt-out dma: swiotlb: Remove SWIOTLB_ANY Documentation/core-api/swiotlb.rst | 8 +- arch/arm/mm/init.c | 6 +- arch/arm/xen/mm.c | 2 +- arch/arm64/mm/init.c | 14 +- arch/loongarch/kernel/setup.c | 2 +- arch/mips/cavium-octeon/dma-octeon.c | 2 +- arch/mips/loongson64/dma.c | 2 +- arch/mips/sibyte/common/dma.c | 2 +- arch/powerpc/kernel/dma-swiotlb.c | 4 +- arch/powerpc/mm/mem.c | 17 ++- arch/powerpc/platforms/pseries/svm.c | 10 -- arch/powerpc/sysdev/fsl_pci.c | 1 + arch/riscv/mm/init.c | 24 +--- arch/s390/mm/init.c | 2 +- arch/x86/include/asm/crash_reserve.h | 4 +- arch/x86/kernel/pci-dma.c | 23 +++- arch/x86/mm/mem_encrypt.c | 24 ---- include/linux/swiotlb.h | 17 ++- kernel/dma/swiotlb.c | 193 +++++++++++++++++++-------- 19 files changed, 210 insertions(+), 147 deletions(-) base-commit: 704340f1cd0dcef829eb62f5b48ae95a2ce17bdf -- 2.43.0
