1 #include <asm/tdx.h> 2 #include <asm/pgtable.h> 3 4 static unsigned long try_accept_one(phys_addr_t start, unsigned long len, 5 enum pg_level pg_level) 6 { 7 unsigned long accept_size = page_level_size(pg_level); 8 u64 tdcall_rcx; 9 u8 page_size; 10 11 if (!IS_ALIGNED(start, accept_size)) 12 return 0; 13 14 if (len < accept_size) 15 return 0; 16 17 /* 18 * Pass the page physical address to the TDX module to accept the 19 * pending, private page. 20 * 21 * Bits 2:0 of RCX encode page size: 0 - 4K, 1 - 2M, 2 - 1G. 22 */ 23 switch (pg_level) { 24 case PG_LEVEL_4K: 25 page_size = 0; 26 break; 27 case PG_LEVEL_2M: 28 page_size = 1; 29 break; 30 case PG_LEVEL_1G: 31 page_size = 2; 32 break; 33 default: 34 return 0; 35 } 36 37 tdcall_rcx = start | page_size; 38 if (__tdx_module_call(TDX_ACCEPT_PAGE, tdcall_rcx, 0, 0, 0, NULL)) 39 return 0; 40 41 return accept_size; 42 } 43 44 bool tdx_accept_memory(phys_addr_t start, phys_addr_t end) 45 { 46 /* 47 * For shared->private conversion, accept the page using 48 * TDX_ACCEPT_PAGE TDX module call. 49 */ 50 while (start < end) { 51 unsigned long len = end - start; 52 unsigned long accept_size; 53 54 /* 55 * Try larger accepts first. It gives chance to VMM to keep 56 * 1G/2M Secure EPT entries where possible and speeds up 57 * process by cutting number of hypercalls (if successful). 58 */ 59 60 accept_size = try_accept_one(start, len, PG_LEVEL_1G); 61 if (!accept_size) 62 accept_size = try_accept_one(start, len, PG_LEVEL_2M); 63 if (!accept_size) 64 accept_size = try_accept_one(start, len, PG_LEVEL_4K); 65 if (!accept_size) 66 return false; 67 start += accept_size; 68 } 69 70 return true; 71 } 72