+#ifndef __LUNAIX_PAGETABLE_H
+#define __LUNAIX_PAGETABLE_H
+
+/*
+ Defines page related attributes for different page table
+ hierarchies. In Lunaix, we define five arch-agnostic alias
+ to those arch-dependent hierarchies:
+
+ + L0T: Level-0 Table, the root page table
+ + L1T: Level-1 Table, indexed by L0P entries
+ + L2T: Level-2 Table, indexed by L1P entries
+ + L3T: Level-3 Table, indexed by L2P entries
+ + LFT: Leaf-Level Table (Level-4), indexed by L3P entries
+
+ Therefore, "LnTE" can be used to refer "Entry in a Level-n Table".
+ Consequently, we can further define
+
+ + LnTEP - pointer to an entry within LnT
+ + LnTP - pointer to (the first entry of) LnT
+
+ To better identify all derived value from virtual and physical
+ adress, we defines:
+
+ + Virtual Address Space (VAS):
+ A set of all virtual addresses that can be interpreted
+ by page table walker.
+
+ + Virtual Mappings Space (VMS):
+ A imaginary linear table compose a set of mappings that
+ define the translation rules from virtual memory address
+ space to physical memory address. (Note: mappings are stored
+ in the hierarchy of page tables, however it is transparent,
+ just as indexing into a big linear table, thus 'imaginary')
+ A VMS is a realisation of a VAS.
+
+ + Virtual Mappings Mounting (VM_MNT or MNT):
+ A subregion within current VAS for where the VA/PA mappings
+ of another VMS are accessible.
+
+ + Page Frame Number (PFN):
+ Index of a page with it's base size. For most machine, it
+ is 4K. Note, this is not limited to physical address, for
+ virtual address, this is the index of a virtual page within
+ it's VMS.
+
+ + Virtual Frame Number (VFN):
+ Index of a virtual page within it's parent page table. It's
+ range is bounded aboved by maximium number of PTEs per page
+ table
+
+ In the context of x86 archiecture (regardless x86_32 or x86_64),
+ these naming have the following realisations:
+
+ + L0T: PD (32-Bit 2-Level paging)
+ PML4 (4-Level Paging)
+ PML5 (5-Level Paging)
+
+ + L1T: ( N/A ) (32-Bit 2-Level paging)
+ PDP (4-Level Paging)
+ PML4 (5-Level Paging)
+
+ + L2T: ( N/A ) (32-Bit 2-Level paging)
+ PD (4-Level Paging)
+ PDP (5-Level Paging)
+
+ + L3T: ( N/A ) (32-Bit 2-Level paging)
+ ( N/A ) (4-Level Paging)
+ PD (5-Level Paging)
+
+ + LFT: Page Table (All)
+
+ + VAS:
+ [0, 2^32) (32-Bit 2-Level paging)
+ [0, 2^48) (4-Level Paging)
+ [0, 2^57) (5-Level Paging)
+
+ + PFN (Vitrual):
+ [0, 2^22) (32-Bit 2-Level paging)
+ [0, 2^36) (4-Level Paging)
+ [0, 2^45) (5-Level Paging)
+
+ + PFN (Physical):
+ [0, 2^32) (x86_32)
+ [0, 2^52) (x86_64, all paging modes)
+
+ + VFN: [0, 1024) (32-Bit 2-Level paging)
+ [0, 512) (4-Level Paging)
+ [0, 512) (5-Level Paging)
+
+ In addition, we also defines VMS_{MASK|SIZE} to provide
+ information about maximium size of addressable virtual
+ memory space (hence VMS). Which is effectively a
+ "Level -1 Page" (i.e., _PAGE_Ln_SIZE(-1))
+
+
+*/
+
+struct __pte;
+typedef struct __pte pte_t;
+
+
+#include <sys/mm/pagetable.h>
+#include <sys/cpu.h>
+
+#define _LnTEP_AT(vm_mnt, sz) ( ((vm_mnt) | L0T_MASK) & ~(sz) )
+#define _L0TEP_AT(vm_mnt) ( ((vm_mnt) | L0T_MASK) & ~LFT_MASK )
+#define _L1TEP_AT(vm_mnt) ( ((vm_mnt) | L0T_MASK) & ~L3T_MASK )
+#define _L2TEP_AT(vm_mnt) ( ((vm_mnt) | L0T_MASK) & ~L2T_MASK )
+#define _L3TEP_AT(vm_mnt) ( ((vm_mnt) | L0T_MASK) & ~L1T_MASK )
+#define _LFTEP_AT(vm_mnt) ( ((vm_mnt) | L0T_MASK) & ~L0T_MASK )
+
+#define _VM_OF(ptep) ( (ptr_t)(ptep) & ~L0T_MASK )
+#define _VM_PFN_OF(ptep) ( ((ptr_t)(ptep) & L0T_MASK) / sizeof(pte_t) )
+#define VMS_SELF ( ~L0T_MASK & VMS_MASK )
+
+#define __LnTI_OF(ptep, n)\
+ (_VM_PFN_OF(ptep) * LFT_SIZE / L##n##T_SIZE)
+
+#define __LnTEP(ptep, va, n)\
+ ( (pte_t*)_L##n##TEP_AT(_VM_OF(ptep)) + (((va) & VMS_MASK) / L##n##T_SIZE) )
+
+#define __LnTEP_OF(ptep, n)\
+ ( (pte_t*)_L##n##TEP_AT(_VM_OF(ptep)) + __LnTI_OF(ptep, n))
+
+#define __LnTEP_SHIFT_NEXT(ptep)\
+ ( (pte_t*)(_VM_OF(ptep) | ((_VM_PFN_OF(ptep) * LFT_SIZE) & L0T_MASK)) )
+
+#define _has_LnT(n) (L##n##T_SIZE != LFT_SIZE)
+#define LnT_ENABLED(n) _has_LnT(n)
+
+#define ptep_with_level(ptep, lvl_size) \
+ ({ \
+ ptr_t __p = _LnTEP_AT(_VM_OF(ptep), lvl_size); \
+ ((ptr_t)(ptep) & __p) == __p; \
+ })
+
+pte_t
+vmm_alloc_page(pte_t* ptep, pte_t pte);
+
+/**
+ * @brief Try page walk to the pte pointed by ptep and
+ * allocate any missing level-table en-route
+ *
+ * @param ptep
+ * @param va
+ */
+void
+ptep_alloc_hierarchy(pte_t* ptep, ptr_t va, pte_attr_t prot);
+
+static inline bool
+__alloc_level(pte_t* ptep, pte_t pte, pte_attr_t prot)
+{
+ if (!pte_isnull(pte)) {
+ return true;
+ }
+
+ pte = pte_setprot(pte, prot);
+ return !pte_isnull(vmm_alloc_page(ptep, pte));
+}
+
+/**
+ * @brief Get the page frame number encoded in ptep
+ *
+ * @param ptep
+ * @return ptr_t
+ */
+static inline ptr_t
+ptep_pfn(pte_t* ptep)
+{
+ return _VM_PFN_OF(ptep);
+}
+
+/**
+ * @brief Get the virtual frame number encoded in ptep
+ *
+ * @param ptep
+ * @return ptr_t
+ */
+static inline unsigned int
+ptep_vfn(pte_t* ptep)
+{
+ return ((ptr_t)ptep & PAGE_MASK) / sizeof(pte_t);
+}
+
+static inline ptr_t
+ptep_va(pte_t* ptep, size_t lvl_size)
+{
+ return ((ptr_t)ptep) / sizeof(pte_t) * lvl_size;
+}
+
+static inline ptr_t
+ptep_vm_mnt(pte_t* ptep)
+{
+ return _VM_OF(ptep);
+}
+
+/**
+ * @brief Make a L0TEP from given ptep
+ *
+ * @param ptep
+ * @return pte_t*
+ */
+static inline pte_t*
+mkl0tep(pte_t* ptep)
+{
+ return __LnTEP_OF(ptep, 0);
+}
+
+/**
+ * @brief Make a L1TEP from given ptep
+ *
+ * @param ptep
+ * @return pte_t*
+ */
+static inline pte_t*
+mkl1tep(pte_t* ptep)
+{
+ return __LnTEP_OF(ptep, 1);
+}
+
+/**
+ * @brief Make a L2TEP from given ptep
+ *
+ * @param ptep
+ * @return pte_t*
+ */
+static inline pte_t*
+mkl2tep(pte_t* ptep)
+{
+ return __LnTEP_OF(ptep, 2);
+}
+
+/**
+ * @brief Make a L3TEP from given ptep
+ *
+ * @param ptep
+ * @return pte_t*
+ */
+static inline pte_t*
+mkl3tep(pte_t* ptep)
+{
+ return __LnTEP_OF(ptep, 3);
+}
+
+/**
+ * @brief Create the L1T pointed by L0TE
+ *
+ * @param l0t_ptep
+ * @param va
+ * @return pte_t*
+ */
+static inline pte_t*
+mkl1t(pte_t* l0t_ptep, ptr_t va, pte_attr_t prot)
+{
+#if _has_LnT(1)
+ if (!l0t_ptep) {
+ return NULL;
+ }
+
+ pte_t pte = pte_at(l0t_ptep);
+
+ if (pte_huge(pte)) {
+ return l0t_ptep;
+ }
+
+ return __alloc_level(l0t_ptep, pte, prot)
+ ? __LnTEP(l0t_ptep, va, 1)
+ : NULL;
+#else
+ return l0t_ptep;
+#endif
+}
+
+/**
+ * @brief Create the L2T pointed by L1TE
+ *
+ * @param l0t_ptep
+ * @param va
+ * @return pte_t*
+ */
+static inline pte_t*
+mkl2t(pte_t* l1t_ptep, ptr_t va, pte_attr_t prot)
+{
+#if _has_LnT(2)
+ if (!l1t_ptep) {
+ return NULL;
+ }
+
+ pte_t pte = pte_at(l1t_ptep);
+
+ if (pte_huge(pte)) {
+ return l1t_ptep;
+ }
+
+ return __alloc_level(l1t_ptep, pte, prot)
+ ? __LnTEP(l1t_ptep, va, 2)
+ : NULL;
+#else
+ return l1t_ptep;
+#endif
+}
+
+/**
+ * @brief Create the L3T pointed by L2TE
+ *
+ * @param l0t_ptep
+ * @param va
+ * @return pte_t*
+ */
+static inline pte_t*
+mkl3t(pte_t* l2t_ptep, ptr_t va, pte_attr_t prot)
+{
+#if _has_LnT(3)
+ if (!l2t_ptep) {
+ return NULL;
+ }
+
+ pte_t pte = pte_at(l2t_ptep);
+
+ if (pte_huge(pte)) {
+ return l2t_ptep;
+ }
+
+ return __alloc_level(l2t_ptep, pte, prot)
+ ? __LnTEP(l2t_ptep, va, 3)
+ : NULL;
+#else
+ return l2t_ptep;
+#endif
+}
+
+/**
+ * @brief Create the LFT pointed by L3TE
+ *
+ * @param l0t_ptep
+ * @param va
+ * @return pte_t*
+ */
+static inline pte_t*
+mklft(pte_t* l3t_ptep, ptr_t va, pte_attr_t prot)
+{
+ if (!l3t_ptep) {
+ return NULL;
+ }
+
+ pte_t pte = pte_at(l3t_ptep);
+
+ if (pte_huge(pte)) {
+ return l3t_ptep;
+ }
+
+ return __alloc_level(l3t_ptep, pte, prot)
+ ? __LnTEP(l3t_ptep, va, F)
+ : NULL;
+}
+
+static inline pte_t*
+getl1tep(pte_t* l0t_ptep, ptr_t va) {
+#if _has_LnT(1)
+ return __LnTEP(l0t_ptep, va, 1);
+#else
+ return l0t_ptep;
+#endif
+}
+
+static inline pte_t*
+getl2tep(pte_t* l1t_ptep, ptr_t va) {
+#if _has_LnT(2)
+ return __LnTEP(l1t_ptep, va, 2);
+#else
+ return l1t_ptep;
+#endif
+}
+
+static inline pte_t*
+getl3tep(pte_t* l2t_ptep, ptr_t va) {
+#if _has_LnT(3)
+ return __LnTEP(l2t_ptep, va, 3);
+#else
+ return l2t_ptep;
+#endif
+}
+
+static inline pte_t*
+getlftep(pte_t* l3t_ptep, ptr_t va) {
+ return __LnTEP(l3t_ptep, va, F);
+}
+
+static inline unsigned int
+l0te_index(pte_t* ptep) {
+ return __LnTI_OF(ptep, 1);
+}
+
+static inline unsigned int
+l1te_index(pte_t* ptep) {
+ return __LnTI_OF(ptep, 2);
+}
+
+static inline unsigned int
+l2te_index(pte_t* ptep) {
+ return __LnTI_OF(ptep, 3);
+}
+
+static inline unsigned int
+l3te_index(pte_t* ptep) {
+ return __LnTI_OF(ptep, F);
+}
+
+static inline pfn_t
+pfn(ptr_t addr) {
+ return (addr / PAGE_SIZE) & VMS_MASK;
+}
+
+static inline size_t
+leaf_count(size_t size) {
+ return (size + PAGE_MASK) / PAGE_SIZE;
+}
+
+static inline size_t
+page_count(size_t size, size_t page_size) {
+ return (size + (page_size - 1)) / page_size;
+}
+
+static inline unsigned int
+va_offset(ptr_t addr) {
+ return addr & PAGE_MASK;
+}
+
+static inline ptr_t
+page_addr(ptr_t pfn) {
+ return pfn * PAGE_SIZE;
+}
+
+static inline ptr_t
+va_align(ptr_t va) {
+ return va & ~PAGE_MASK;
+}
+
+static inline ptr_t
+va_alignup(ptr_t va) {
+ return (va + PAGE_MASK) & ~PAGE_MASK;
+}
+
+static inline pte_t*
+mkptep_va(ptr_t vm_mnt, ptr_t vaddr)
+{
+ return (pte_t*)(vm_mnt & ~L0T_MASK) + pfn(vaddr);
+}
+
+static inline pte_t*
+mkptep_pn(ptr_t vm_mnt, ptr_t pn)
+{
+ return (pte_t*)(vm_mnt & ~L0T_MASK) + (pn & L0T_MASK);
+}
+
+static inline pfn_t
+pfn_at(ptr_t va, size_t lvl_size) {
+ return va / lvl_size;
+}
+
+
+/**
+ * @brief Shift the ptep such that it points to an
+ * immediate lower level of page table
+ *
+ * @param ptep
+ * @return pte_t*
+ */
+static inline pte_t*
+ptep_step_into(pte_t* ptep)
+{
+ return __LnTEP_SHIFT_NEXT(ptep);
+}
+
+/**
+ * @brief Shift the ptep such that it points to an
+ * immediate upper level of page table
+ *
+ * @param ptep
+ * @return pte_t*
+ */
+static inline pte_t*
+ptep_step_out(pte_t* ptep)
+{
+ ptr_t unshifted = (ptr_t)mkptep_pn(VMS_SELF, ptep_pfn(ptep));
+ return mkptep_va(_VM_OF(ptep), unshifted);
+}
+
+/**
+ * @brief Make a L0TEP from given mnt and va
+ *
+ * @param ptep
+ * @return pte_t*
+ */
+static inline pte_t*
+mkl0tep_va(ptr_t mnt, ptr_t va)
+{
+ return mkl0tep(mkptep_va(mnt, va));
+}
+
+static inline bool
+pt_last_level(int level)
+{
+ return level == _PTW_LEVEL - 1;
+}
+
+#endif /* __LUNAIX_PAGETABLE_H */
git://scm.lunaixsky.com / lunaix-os.git / commitdiff
