[v8,11/16] x86/virt/tdx: Designate reserved areas for all TDMRs

Message ID	27dcd2781a450b3f77a2aec833de6a3669bc0fb8.1670566861.git.kai.huang@intel.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <kvm-owner@kernel.org> From: Kai Huang <kai.huang@intel.com> To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org Cc: linux-mm@kvack.org, dave.hansen@intel.com, peterz@infradead.org, tglx@linutronix.de, seanjc@google.com, pbonzini@redhat.com, dan.j.williams@intel.com, rafael.j.wysocki@intel.com, kirill.shutemov@linux.intel.com, ying.huang@intel.com, reinette.chatre@intel.com, len.brown@intel.com, tony.luck@intel.com, ak@linux.intel.com, isaku.yamahata@intel.com, chao.gao@intel.com, sathyanarayanan.kuppuswamy@linux.intel.com, bagasdotme@gmail.com, sagis@google.com, imammedo@redhat.com, kai.huang@intel.com Subject: [PATCH v8 11/16] x86/virt/tdx: Designate reserved areas for all TDMRs Date: Fri, 9 Dec 2022 19:52:32 +1300 Message-Id: <27dcd2781a450b3f77a2aec833de6a3669bc0fb8.1670566861.git.kai.huang@intel.com> In-Reply-To: <cover.1670566861.git.kai.huang@intel.com> References: <cover.1670566861.git.kai.huang@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk
Series	TDX host kernel support \| expand [v8,00/16] TDX host kernel support [v8,01/16] x86/tdx: Define TDX supported page sizes as macros [v8,02/16] x86/virt/tdx: Detect TDX during kernel boot [v8,03/16] x86/virt/tdx: Make INTEL_TDX_HOST depend on X86_X2APIC [v8,04/16] x86/virt/tdx: Add skeleton to initialize TDX on demand [v8,05/16] x86/virt/tdx: Implement functions to make SEAMCALL [v8,06/16] x86/virt/tdx: Get information about TDX module and TDX-capable memory [v8,07/16] x86/virt/tdx: Use all system memory when initializing TDX module as TDX memory [v8,08/16] x86/virt/tdx: Add placeholder to construct TDMRs to cover all TDX memory regions [v8,09/16] x86/virt/tdx: Fill out TDMRs to cover all TDX memory regions [v8,10/16] x86/virt/tdx: Allocate and set up PAMTs for TDMRs [v8,11/16] x86/virt/tdx: Designate reserved areas for all TDMRs [v8,12/16] x86/virt/tdx: Designate the global KeyID and configure the TDX module [v8,13/16] x86/virt/tdx: Configure global KeyID on all packages [v8,14/16] x86/virt/tdx: Initialize all TDMRs [v8,15/16] x86/virt/tdx: Flush cache in kexec() when TDX is enabled [v8,16/16] Documentation/x86: Add documentation for TDX host support

diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c index cf970a783f1f..620b35e2a61b 100644 --- a/arch/x86/virt/vmx/tdx/tdx.c +++ b/arch/x86/virt/vmx/tdx/tdx.c @@ -21,6 +21,7 @@ #include <linux/sizes.h> #include <linux/pfn.h> #include <linux/align.h> +#include <linux/sort.h> #include <asm/pgtable_types.h> #include <asm/msr.h> #include <asm/tdx.h> @@ -687,6 +688,202 @@ static unsigned long tdmrs_count_pamt_pages(struct tdmr_info_list *tdmr_list) return pamt_npages; } +static int tdmr_add_rsvd_area(struct tdmr_info *tdmr, int *p_idx, u64 addr, + u64 size, u16 max_reserved_per_tdmr) +{ + struct tdmr_reserved_area *rsvd_areas = tdmr->reserved_areas; + int idx = *p_idx; + + /* Reserved area must be 4K aligned in offset and size */ + if (WARN_ON(addr & ~PAGE_MASK || size & ~PAGE_MASK)) + return -EINVAL; + + if (idx >= max_reserved_per_tdmr) + return -E2BIG; + + rsvd_areas[idx].offset = addr - tdmr->base; + rsvd_areas[idx].size = size; + + *p_idx = idx + 1; + + return 0; +} + +/* + * Go through @tmb_list to find holes between memory areas. If any of + * those holes fall within @tdmr, set up a TDMR reserved area to cover + * the hole. + */ +static int tdmr_populate_rsvd_holes(struct list_head *tmb_list, + struct tdmr_info *tdmr, + int *rsvd_idx, + u16 max_reserved_per_tdmr) +{ + struct tdx_memblock *tmb; + u64 prev_end; + int ret; + + /* + * Start looking for reserved blocks at the + * beginning of the TDMR. + */ + prev_end = tdmr->base; + list_for_each_entry(tmb, tmb_list, list) { + u64 start, end; + + start = PFN_PHYS(tmb->start_pfn); + end = PFN_PHYS(tmb->end_pfn); + + /* Break if this region is after the TDMR */ + if (start >= tdmr_end(tdmr)) + break; + + /* Exclude regions before this TDMR */ + if (end < tdmr->base) + continue; + + /* + * Skip over memory areas that + * have already been dealt with. + */ + if (start <= prev_end) { + prev_end = end; + continue; + } + + /* Add the hole before this region */ + ret = tdmr_add_rsvd_area(tdmr, rsvd_idx, prev_end, + start - prev_end, + max_reserved_per_tdmr); + if (ret) + return ret; + + prev_end = end; + } + + /* Add the hole after the last region if it exists. */ + if (prev_end < tdmr_end(tdmr)) { + ret = tdmr_add_rsvd_area(tdmr, rsvd_idx, prev_end, + tdmr_end(tdmr) - prev_end, + max_reserved_per_tdmr); + if (ret) + return ret; + } + + return 0; +} + +/* + * Go through @tdmr_list to find all PAMTs. If any of those PAMTs + * overlaps with @tdmr, set up a TDMR reserved area to cover the + * overlapping part. + */ +static int tdmr_populate_rsvd_pamts(struct tdmr_info_list *tdmr_list, + struct tdmr_info *tdmr, + int *rsvd_idx, + u16 max_reserved_per_tdmr) +{ + int i, ret; + + for (i = 0; i < tdmr_list->nr_tdmrs; i++) { + struct tdmr_info *tmp = tdmr_entry(tdmr_list, i); + unsigned long pamt_start_pfn, pamt_npages; + u64 pamt_start, pamt_end; + + tdmr_get_pamt(tmp, &pamt_start_pfn, &pamt_npages); + /* Each TDMR must already have PAMT allocated */ + WARN_ON_ONCE(!pamt_npages || !pamt_start_pfn); + + pamt_start = PFN_PHYS(pamt_start_pfn); + pamt_end = PFN_PHYS(pamt_start_pfn + pamt_npages); + + /* Skip PAMTs outside of the given TDMR */ + if ((pamt_end <= tdmr->base) || + (pamt_start >= tdmr_end(tdmr))) + continue; + + /* Only mark the part within the TDMR as reserved */ + if (pamt_start < tdmr->base) + pamt_start = tdmr->base; + if (pamt_end > tdmr_end(tdmr)) + pamt_end = tdmr_end(tdmr); + + ret = tdmr_add_rsvd_area(tdmr, rsvd_idx, pamt_start, + pamt_end - pamt_start, + max_reserved_per_tdmr); + if (ret) + return ret; + } + + return 0; +} + +/* Compare function called by sort() for TDMR reserved areas */ +static int rsvd_area_cmp_func(const void *a, const void *b) +{ + struct tdmr_reserved_area *r1 = (struct tdmr_reserved_area *)a; + struct tdmr_reserved_area *r2 = (struct tdmr_reserved_area *)b; + + if (r1->offset + r1->size <= r2->offset) + return -1; + if (r1->offset >= r2->offset + r2->size) + return 1; + + /* Reserved areas cannot overlap. The caller must guarantee. */ + WARN_ON_ONCE(1); + return -1; +} + +/* + * Populate reserved areas for the given @tdmr, including memory holes + * (via @tmb_list) and PAMTs (via @tdmr_list). + */ +static int tdmr_populate_rsvd_areas(struct tdmr_info *tdmr, + struct list_head *tmb_list, + struct tdmr_info_list *tdmr_list, + u16 max_reserved_per_tdmr) +{ + int ret, rsvd_idx = 0; + + ret = tdmr_populate_rsvd_holes(tmb_list, tdmr, &rsvd_idx, + max_reserved_per_tdmr); + if (ret) + return ret; + + ret = tdmr_populate_rsvd_pamts(tdmr_list, tdmr, &rsvd_idx, + max_reserved_per_tdmr); + if (ret) + return ret; + + /* TDX requires reserved areas listed in address ascending order */ + sort(tdmr->reserved_areas, rsvd_idx, sizeof(struct tdmr_reserved_area), + rsvd_area_cmp_func, NULL); + + return 0; +} + +/* + * Populate reserved areas for all TDMRs in @tdmr_list, including memory + * holes (via @tmb_list) and PAMTs. + */ +static int tdmrs_populate_rsvd_areas_all(struct tdmr_info_list *tdmr_list, + struct list_head *tmb_list, + u16 max_reserved_per_tdmr) +{ + int i; + + for (i = 0; i < tdmr_list->nr_tdmrs; i++) { + int ret; + + ret = tdmr_populate_rsvd_areas(tdmr_entry(tdmr_list, i), + tmb_list, tdmr_list, max_reserved_per_tdmr); + if (ret) + return ret; + } + + return 0; +} + /* * Construct a list of TDMRs on the preallocated space in @tdmr_list * to cover all TDX memory regions in @tmb_list based on the TDX module @@ -706,14 +903,14 @@ static int construct_tdmrs(struct list_head *tmb_list, sysinfo->pamt_entry_size); if (ret) goto err; - /* - * TODO: - * - * - Designate reserved areas for each TDMR. - * - * Return -EINVAL until constructing TDMRs is done - */ - ret = -EINVAL; + + ret = tdmrs_populate_rsvd_areas_all(tdmr_list, tmb_list, + sysinfo->max_reserved_per_tdmr); + if (ret) + goto err_free_pamts; + + return 0; +err_free_pamts: tdmrs_free_pamt_all(tdmr_list); err: return ret;

[v8,11/16] x86/virt/tdx: Designate reserved areas for all TDMRs

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