PATENT CLAIM ANALYSIS

Application Number: 15949940
Application Type: Utility
Filing Date: 2018-04
Publication Date: 2018-08
Patent Classification: ["711", "006000"]

Abstract:
An input-output (IO) memory management unit (IOMMU) uses a reverse map table (RMT) to ensure that address translations acquired from a nested page table are correct and that IO devices are permitted to access pages in a memory when performing memory accesses in a computing device. A translation lookaside buffer (TLB) flushing mechanism is used to invalidate address translation information in TLBs that are affected by changes in the RMT. A modified Address Translation Caching (ATC) mechanism may be used, in which only partial address translation information is provided to IO devices so that the RMT is checked when performing memory accesses for the IO devices using the cached address translation information.

Claim (Index 1):
An apparatus, comprising:\n an input-output (IO) device; an input-output memory management unit (IOMMU) comprising an IO table walker; and a memory that stores a reverse map table (RMT), a nested page table, and a plurality of pages of memory; wherein the IO table walker is configured to:\n receive, based on an access request from the IO device, a request to translate an IO device virtual address into a system physical address associated with a page of memory; \n use a guest physical address associated with the IO device virtual address to acquire the system physical address from a corresponding entry in the nested page table; \n perform one or more checks in the RMT to ensure that the guest physical address is correctly mapped to the system physical address in the nested page table and that the IO device has access to the page; and \n when the guest physical address is correctly mapped to the system physical address in the nested page table and the IO device has access to the page, provide the system physical address for use in performing the access for the IO device.

Metadata:
- Claim Count in Document: 9.0
- Percentile: 91.0
- Lexical Diversity: 1.77465
- Patent Class: 711.0
- Transitional Phrase Type: open
- Component Type: 1
- Foreign Priority: False
- Related Applications: ['15907593', '15224302', '15417632', '14589693', '12508882']

Analysis Scores:
- 35 USC 101 Eligibility (BERT): 0.5624471474658395
- 35 USC 102 Novelty (BERT): 0.5308930529058348
- Combined Prediction Score: 0.559291738009839
- Mean Citation Score: 316.555534
- Max Citation Score: 373.65195
- Similarity Product: 334.53445525999365

Labels:
- Claim Label 101: 1
- Claim Label 102: 1
- Claim Label 103: 1
- Claim Label 112: 1
- Combined Label: 1
- Label 101 Adjusted: 1

Dataset: test