Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
nitro_enclaves: Merge contiguous physical memory regions
There can be cases when there are more memory regions that need to be
set for an enclave than the maximum supported number of memory regions
per enclave. One example can be when the memory regions are backed by 2
MiB hugepages (the minimum supported hugepage size).
Let's merge the adjacent regions if they are physically contiguous. This
way the final number of memory regions is less than before merging and
could potentially avoid reaching maximum.
Reviewed-by: Andra Paraschiv <andraprs@amazon.com>
Signed-off-by: Longpeng <longpeng2@huawei.com>
Link: https://lore.kernel.org/r/20211107140918.2106-2-longpeng2@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
authored by
Longpeng
and committed by
Greg Kroah-Hartman
f6bdc0aa
dc74e8cf
+56
-28
+56
-28
drivers/virt/nitro_enclaves/ne_misc_dev.c
+56
-28
drivers/virt/nitro_enclaves/ne_misc_dev.c
···
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#include <linux/nitro_enclaves.h>
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#include <linux/pci.h>
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#include <linux/poll.h>
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#include <linux/range.h>
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#include <linux/slab.h>
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#include <linux/types.h>
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#include <uapi/linux/vm_sockets.h>
···
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};
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static struct ne_cpu_pool ne_cpu_pool;
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/**
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* struct ne_phys_contig_mem_regions - Contiguous physical memory regions.
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* @num: The number of regions that currently has.
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* @regions: The array of physical memory regions.
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*/
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struct ne_phys_contig_mem_regions {
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unsigned long num;
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struct range *regions;
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};
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/**
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* ne_check_enclaves_created() - Verify if at least one enclave has been created.
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}
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/**
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* ne_merge_phys_contig_memory_regions() - Add a memory region and merge the adjacent
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* regions if they are physically contiguous.
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* @phys_contig_regions : Private data associated with the contiguous physical memory regions.
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* @page_paddr : Physical start address of the region to be added.
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* @page_size : Length of the region to be added.
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*
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* Context: Process context. This function is called with the ne_enclave mutex held.
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*/
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static void
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ne_merge_phys_contig_memory_regions(struct ne_phys_contig_mem_regions *phys_contig_regions,
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u64 page_paddr, u64 page_size)
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{
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unsigned long num = phys_contig_regions->num;
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/* Physically contiguous, just merge */
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if (num && (phys_contig_regions->regions[num - 1].end + 1) == page_paddr) {
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phys_contig_regions->regions[num - 1].end += page_size;
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return;
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}
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phys_contig_regions->regions[num].start = page_paddr;
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phys_contig_regions->regions[num].end = page_paddr + page_size - 1;
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phys_contig_regions->num++;
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}
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/**
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* ne_set_user_memory_region_ioctl() - Add user space memory region to the slot
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* associated with the current enclave.
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* @ne_enclave : Private data associated with the current enclave.
···
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unsigned long max_nr_pages = 0;
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unsigned long memory_size = 0;
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struct ne_mem_region *ne_mem_region = NULL;
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unsigned long nr_phys_contig_mem_regions = 0;
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struct pci_dev *pdev = ne_devs.ne_pci_dev->pdev;
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struct page **phys_contig_mem_regions = NULL;
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struct ne_phys_contig_mem_regions phys_contig_mem_regions = {};
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int rc = -EINVAL;
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rc = ne_sanity_check_user_mem_region(ne_enclave, mem_region);
···
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goto free_mem_region;
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}
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phys_contig_mem_regions = kcalloc(max_nr_pages, sizeof(*phys_contig_mem_regions),
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GFP_KERNEL);
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if (!phys_contig_mem_regions) {
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phys_contig_mem_regions.regions = kcalloc(max_nr_pages,
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sizeof(*phys_contig_mem_regions.regions),
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GFP_KERNEL);
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if (!phys_contig_mem_regions.regions) {
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rc = -ENOMEM;
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goto free_mem_region;
···
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if (rc < 0)
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goto put_pages;
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/*
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* TODO: Update once handled non-contiguous memory regions
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* received from user space or contiguous physical memory regions
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* larger than 2 MiB e.g. 8 MiB.
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*/
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phys_contig_mem_regions[i] = ne_mem_region->pages[i];
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ne_merge_phys_contig_memory_regions(&phys_contig_mem_regions,
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page_to_phys(ne_mem_region->pages[i]),
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page_size(ne_mem_region->pages[i]));
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memory_size += page_size(ne_mem_region->pages[i]);
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ne_mem_region->nr_pages++;
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} while (memory_size < mem_region.memory_size);
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/*
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* TODO: Update once handled non-contiguous memory regions received
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* from user space or contiguous physical memory regions larger than
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* 2 MiB e.g. 8 MiB.
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*/
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nr_phys_contig_mem_regions = ne_mem_region->nr_pages;
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if ((ne_enclave->nr_mem_regions + nr_phys_contig_mem_regions) >
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if ((ne_enclave->nr_mem_regions + phys_contig_mem_regions.num) >
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ne_enclave->max_mem_regions) {
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dev_err_ratelimited(ne_misc_dev.this_device,
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"Reached max memory regions %lld\n",
···
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goto put_pages;
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}
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for (i = 0; i < nr_phys_contig_mem_regions; i++) {
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u64 phys_region_addr = page_to_phys(phys_contig_mem_regions[i]);
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u64 phys_region_size = page_size(phys_contig_mem_regions[i]);
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for (i = 0; i < phys_contig_mem_regions.num; i++) {
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u64 phys_region_addr = phys_contig_mem_regions.regions[i].start;
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u64 phys_region_size = range_len(&phys_contig_mem_regions.regions[i]);
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if (phys_region_size & (NE_MIN_MEM_REGION_SIZE - 1)) {
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dev_err_ratelimited(ne_misc_dev.this_device,
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list_add(&ne_mem_region->mem_region_list_entry, &ne_enclave->mem_regions_list);
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for (i = 0; i < nr_phys_contig_mem_regions; i++) {
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for (i = 0; i < phys_contig_mem_regions.num; i++) {
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struct ne_pci_dev_cmd_reply cmd_reply = {};
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struct slot_add_mem_req slot_add_mem_req = {};
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slot_add_mem_req.slot_uid = ne_enclave->slot_uid;
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slot_add_mem_req.paddr = page_to_phys(phys_contig_mem_regions[i]);
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slot_add_mem_req.size = page_size(phys_contig_mem_regions[i]);
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slot_add_mem_req.paddr = phys_contig_mem_regions.regions[i].start;
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slot_add_mem_req.size = range_len(&phys_contig_mem_regions.regions[i]);
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rc = ne_do_request(pdev, SLOT_ADD_MEM,
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&slot_add_mem_req, sizeof(slot_add_mem_req),
···
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dev_err_ratelimited(ne_misc_dev.this_device,
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"Error in slot add mem [rc=%d]\n", rc);
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kfree(phys_contig_mem_regions);
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kfree(phys_contig_mem_regions.regions);
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/*
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* Exit here without put pages as memory regions may
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ne_enclave->nr_mem_regions++;
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}
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kfree(phys_contig_mem_regions);
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kfree(phys_contig_mem_regions.regions);
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return 0;
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···
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for (i = 0; i < ne_mem_region->nr_pages; i++)
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put_page(ne_mem_region->pages[i]);
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free_mem_region:
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kfree(phys_contig_mem_regions);
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kfree(phys_contig_mem_regions.regions);
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kfree(ne_mem_region->pages);
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kfree(ne_mem_region);
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