From: Pasha Tatashin <tatashin@xxxxxxxxxx> IOMMU subsystem may contain state that is in gigabytes. Majority of that state is iommu page tables. Yet, there is currently, no way to observe how much memory is actually used by the iommu subsystem. This patch series solves this problem by adding both observability to all pages that are allocated by IOMMU, and also accountability, so admins can limit the amount if via cgroups. The system-wide observability is using /proc/meminfo: SecPageTables: 438176 kB Contains IOMMU and KVM memory. Per-node observability: /sys/devices/system/node/nodeN/meminfo Node N SecPageTables: 422204 kB Contains IOMMU and KVM memory memory in the given NUMA node. Per-node IOMMU only observability: /sys/devices/system/node/nodeN/vmstat nr_iommu_pages 105555 Contains number of pages IOMMU allocated in the given node. Accountability: using sec_pagetables cgroup-v2 memory.stat entry. With the change, iova_stress[1] stops as limit is reached: # ./iova_stress iova space: 0T free memory: 497G iova space: 1T free memory: 495G iova space: 2T free memory: 493G iova space: 3T free memory: 491G stops as limit is reached. This series encorporates suggestions that came from the discussion at LPC [2]. [1] https://github.com/soleen/iova_stress [2] https://lpc.events/event/17/contributions/1466 Pasha Tatashin (16): iommu/vt-d: add wrapper functions for page allocations iommu/amd: use page allocation function provided by iommu-pages.h iommu/io-pgtable-arm: use page allocation function provided by iommu-pages.h iommu/io-pgtable-dart: use page allocation function provided by iommu-pages.h iommu/io-pgtable-arm-v7s: use page allocation function provided by iommu-pages.h iommu/dma: use page allocation function provided by iommu-pages.h iommu/exynos: use page allocation function provided by iommu-pages.h iommu/fsl: use page allocation function provided by iommu-pages.h iommu/iommufd: use page allocation function provided by iommu-pages.h iommu/rockchip: use page allocation function provided by iommu-pages.h iommu/sun50i: use page allocation function provided by iommu-pages.h iommu/tegra-smmu: use page allocation function provided by iommu-pages.h iommu: observability of the IOMMU allocations iommu: account IOMMU allocated memory vhost-vdpa: account iommu allocations vfio: account iommu allocations Documentation/admin-guide/cgroup-v2.rst | 2 +- Documentation/filesystems/proc.rst | 4 +- drivers/iommu/amd/amd_iommu.h | 8 - drivers/iommu/amd/init.c | 91 +++++----- drivers/iommu/amd/io_pgtable.c | 13 +- drivers/iommu/amd/io_pgtable_v2.c | 20 +- drivers/iommu/amd/iommu.c | 13 +- drivers/iommu/dma-iommu.c | 8 +- drivers/iommu/exynos-iommu.c | 14 +- drivers/iommu/fsl_pamu.c | 5 +- drivers/iommu/intel/dmar.c | 10 +- drivers/iommu/intel/iommu.c | 47 ++--- drivers/iommu/intel/iommu.h | 2 - drivers/iommu/intel/irq_remapping.c | 10 +- drivers/iommu/intel/pasid.c | 12 +- drivers/iommu/intel/svm.c | 7 +- drivers/iommu/io-pgtable-arm-v7s.c | 9 +- drivers/iommu/io-pgtable-arm.c | 7 +- drivers/iommu/io-pgtable-dart.c | 37 ++-- drivers/iommu/iommu-pages.h | 231 ++++++++++++++++++++++++ drivers/iommu/iommufd/iova_bitmap.c | 6 +- drivers/iommu/rockchip-iommu.c | 14 +- drivers/iommu/sun50i-iommu.c | 7 +- drivers/iommu/tegra-smmu.c | 18 +- drivers/vfio/vfio_iommu_type1.c | 8 +- drivers/vhost/vdpa.c | 3 +- include/linux/mmzone.h | 5 +- mm/vmstat.c | 3 + 28 files changed, 415 insertions(+), 199 deletions(-) create mode 100644 drivers/iommu/iommu-pages.h -- 2.43.0.rc2.451.g8631bc7472-goog
