similar to: [PATCH v2 0/5] mm/hmm/nouveau: add PMD system memory mapping

The goal for this series is to introduce the hmm_pfn_to_map_order() function. This allows a device driver to know that a given 4K PFN is actually mapped by the CPU using a larger sized CPU page table entry and therefore the device driver can safely map system memory using larger device MMU PTEs. The series is based on 5.8.0-rc3 and is intended for Jason Gunthorpe's hmm tree. These were

hmm_range_fault() returns an array of page frame numbers and flags for how the pages are mapped in the requested process' page tables. The PFN can be used to get the struct page with hmm_pfn_to_page() and the page size order can be determined with compound_order(page) but if the page is larger than order 0 (PAGE_SIZE), there is no indication that the page is mapped using a larger page size. To

These patches apply to linux-5.8.0-rc1. Patches 1-3 should probably go into 5.8, the others can be queued for 5.9. Patches 4-6 improve the HMM self tests. Patch 7-8 prepare nouveau for the meat of this series which adds support and testing for compound page mapping of system memory (patches 9-11) and compound page migration to device private memory (patches 12-16). Since these changes are split

From: Jason Gunthorpe <jgg at mellanox.com> The API is a bit complicated for the uses we actually have, and disucssions for simplifying have come up a number of times. This small series removes the customizable pfn format and simplifies the return code of hmm_range_fault() All the drivers are adjusted to process in the simplified format. I would appreciated tested-by's for the two

From: Jason Gunthorpe <jgg at mellanox.com> The API is a bit complicated for the uses we actually have, and disucssions for simplifying have come up a number of times. This small series removes the customizable pfn format and simplifies the return code of hmm_range_fault() All the drivers are adjusted to process in the simplified format. I would appreciated tested-by's for the two

On 2020-05-01 11:20, Jason Gunthorpe wrote: > From: Jason Gunthorpe <jgg at mellanox.com> > > Presumably the intent here was that hmm_range_fault() could put the data > into some HW specific format and thus avoid some work. However, nothing > actually does that, and it isn't clear how anything actually could do that > as hmm_range_fault() provides CPU addresses which

On Tue, Apr 21, 2020 at 09:21:46PM -0300, Jason Gunthorpe wrote: > +void nouveau_hmm_convert_pfn(struct nouveau_drm *drm, struct hmm_range *range, > + u64 *ioctl_addr) > { > unsigned long i, npages; > > + /* > + * The ioctl_addr prepared here is passed through nvif_object_ioctl() > + * to an eventual DMA map on some call chain like: > + *

When acting on device private mappings a driver needs to know if the device (or other entity in case of kvmppc) actually owns this private mapping. This series adds an owner field and converts the migrate_vma code over to check it. I looked into doing the same for hmm_range_fault, but as far as I can tell that code has never been wired up to actually work for device private memory, so instead of

Nouveau currently only supports mapping PAGE_SIZE sized pages of system memory when shared virtual memory (SVM) is enabled. Use the new HMM_PFN_COMPOUND flag that hmm_range_fault() returns to support mapping system memory pages larger than PAGE_SIZE. Signed-off-by: Ralph Campbell <rcampbell at nvidia.com> --- drivers/gpu/drm/nouveau/nouveau_svm.c | 47 ++++++++++++++-----

The SVM page fault handler groups faults into a range of contiguous virtual addresses and requests hmm_range_fault() to populate and return the page frame number of system memory mapped by the CPU. In preparation for supporting large pages to be mapped by the GPU, process faults one page at a time. In addition, use the hmm_range default_flags to fix a corner case where the input hmm_pfns array is

The SVM page fault handler groups faults into a range of contiguous virtual addresses and requests hmm_range_fault() to populate and return the page frame number of system memory mapped by the CPU. In preparation for supporting large pages to be mapped by the GPU, process faults one page at a time. In addition, use the hmm_range default_flags to fix a corner case where the input hmm_pfns array is

hmm_range_fault() returns an array of page frame numbers and flags for how the pages are mapped in the requested process' page tables. The PFN can be used to get the struct page with hmm_pfn_to_page() and the page size order can be determined with compound_order(page) but if the page is larger than order 0 (PAGE_SIZE), there is no indication that a compound page is mapped by the CPU using a

From: Jason Gunthorpe <jgg at mellanox.com> Presumably the intent here was that hmm_range_fault() could put the data into some HW specific format and thus avoid some work. However, nothing actually does that, and it isn't clear how anything actually could do that as hmm_range_fault() provides CPU addresses which must be DMA mapped. Perhaps there is some special HW that does not need

[+Philip Yang] Am 2020-04-21 um 8:21 p.m. schrieb Jason Gunthorpe: > From: Jason Gunthorpe <jgg at mellanox.com> > > Presumably the intent here was that hmm_range_fault() could put the data > into some HW specific format and thus avoid some work. However, nothing > actually does that, and it isn't clear how anything actually could do that > as hmm_range_fault()

From: Jason Gunthorpe <jgg at mellanox.com> Presumably the intent here was that hmm_range_fault() could put the data into some HW specific format and thus avoid some work. However, nothing actually does that, and it isn't clear how anything actually could do that as hmm_range_fault() provides CPU addresses which must be DMA mapped. Perhaps there is some special HW that does not need

From: Jérôme Glisse <jglisse at redhat.com> (mm is cced just to allow exposure of device driver work without ccing a long list of peoples. I do not think there is anything usefull to discuss from mm point of view but i might be wrong, so just for the curious :)). git://people.freedesktop.org/~glisse/linux branch: nouveau-hmm-v00

Hi Jérôme, Ben, Felxi and Jason, below is a series against the hmm tree which cleans up various minor bits and allows HMM_MIRROR to be built on all architectures. Diffstat: 7 files changed, 81 insertions(+), 171 deletions(-) A git tree is also available at: git://git.infradead.org/users/hch/misc.git hmm-cleanups Gitweb:

Hi Jérôme, Ben, Felix and Jason, below is a series against the hmm tree which cleans up various minor bits and allows HMM_MIRROR to be built on all architectures. Diffstat: 11 files changed, 94 insertions(+), 210 deletions(-) A git tree is also available at: git://git.infradead.org/users/hch/misc.git hmm-cleanups.2 Gitweb:

From: Jason Gunthorpe <jgg at mellanox.com> 8 of the mmu_notifier using drivers (i915_gem, radeon_mn, umem_odp, hfi1, scif_dma, vhost, gntdev, hmm) drivers are using a common pattern where they only use invalidate_range_start/end and immediately check the invalidating range against some driver data structure to tell if the driver is interested. Half of them use an interval_tree, the others

This series adds new functions to the mmu interval notifier API to allow device drivers with MMUs to dynamically mirror a process' page tables based on device faults and invalidation callbacks. The Nouveau driver is updated to use the extended API and a set of stand alone self tests is added to help validate and maintain correctness. The patches are based on linux-5.5.0-rc6 and are for