Improve cake allocator's memory utilisation (#43)

[lunaix-os.git] / lunaix-os / includes / lunaix / mm / page.h

diff --git a/lunaix-os/includes/lunaix/mm/page.h b/lunaix-os/includes/lunaix/mm/page.h
index 087e4551bae7c91982cb8eb59233548a172245e3..da7cab42fa42d8e6478638ac65a05e0d75a0ae57 100644 (file)
--- a/lunaix-os/includes/lunaix/mm/page.h
+++ b/lunaix-os/includes/lunaix/mm/page.h
@@ -1,117 +1,324 @@
 #ifndef __LUNAIX_PAGE_H
 #define __LUNAIX_PAGE_H
 #ifndef __LUNAIX_PAGE_H
 #define __LUNAIX_PAGE_H

-#include <lunaix/common.h>
-#include <stdint.h>

 
 

-#define PG_SIZE_BITS 12
-#define PG_SIZE (1 << PG_SIZE_BITS)
-#define PG_INDEX_BITS 10
+#include <lunaix/mm/pmm.h>
+#include <lunaix/mm/vmm.h>
+#include <lunaix/mm/vmtlb.h>

 
 

-#define PG_MAX_ENTRIES 1024U
-#define PG_LAST_TABLE PG_MAX_ENTRIES - 1
-#define PG_FIRST_TABLE 0
+#include <klibc/string.h>

 
 

-#define PTE_NULL 0
+/**
+ * @brief A leaflet represent a bunch 4k ppage
+ *        as single multi-ordered page, as such
+ *        big page can seen as an unfolded version
+ *        of these small 4k ppages hence the name.
+ *        It is introduced to solve the issue that
+ *        is discovered during refactoring - It is 
+ *        jolly unclear whether the ppage is a head, 
+ *        tail, or even worse, the middle one, when
+ *        passing around between functions.
+ *        This concept is surprisingly similar to
+ *        Linux's struct folio (I swear to the 
+ *        Almighty Princess of the Sun, Celestia, 
+ *        that I don't quite understand what folio 
+ *        is until I've wrote the conceptually same 
+ *        thing)
+ * 
+ */
+struct leaflet
+{
+    struct ppage lead_page;
+};
+
+static inline struct leaflet*
+get_leaflet(struct ppage* page)
+{
+    return (struct leaflet*)leading_page(page);
+}
+
+static inline struct ppage*
+get_ppage(struct leaflet* leaflet)
+{
+    return (struct ppage*)leaflet;
+}
+
+static inline struct leaflet*
+alloc_leaflet(int order)
+{
+    return (struct leaflet*)pmm_alloc_napot_type(POOL_UNIFIED, order, 0);
+}
+
+static inline struct leaflet*
+alloc_leaflet_pinned(int order)
+{
+    return (struct leaflet*)pmm_alloc_napot_type(POOL_UNIFIED, order, PP_FGLOCKED);
+}
+
+static inline void
+leaflet_borrow(struct leaflet* leaflet)
+{
+    struct ppage* const page = get_ppage(leaflet);
+    assert(page->refs);
+    if (reserved_page(page)) {
+        return;
+    }
+    
+    page->refs++;
+}
+
+static inline void
+leaflet_return(struct leaflet* leaflet)
+{
+    struct ppage* const page = get_ppage(leaflet);
+    assert(page->refs);
+    pmm_free_one(page, 0);
+}
+
+static inline unsigned int
+leaflet_refcount(struct leaflet* leaflet)
+{
+    return get_ppage(leaflet)->refs;
+}
+
+static inline int
+leaflet_order(struct leaflet* leaflet)
+{
+    return ppage_order(get_ppage(leaflet));
+}
+
+static inline int
+leaflet_size(struct leaflet* leaflet)
+{
+    return PAGE_SIZE << leaflet_order(leaflet);
+}
+
+static inline int
+leaflet_nfold(struct leaflet* leaflet)
+{
+    return 1 << leaflet_order(leaflet);
+}
+
+static inline struct leaflet*
+ppfn_leaflet(pfn_t ppfn)
+{
+    return get_leaflet(ppage(ppfn));
+}
+
+static inline struct leaflet*
+pte_leaflet(pte_t pte)
+{
+    struct ppage* ppfn = ppage(pfn(pte_paddr(pte)));
+    return get_leaflet(ppfn);
+}

 
 

-#define P2V(paddr) ((uintptr_t)(paddr) + KERNEL_MM_BASE)
-#define V2P(vaddr) ((uintptr_t)(vaddr)-KERNEL_MM_BASE)
+static inline struct leaflet*
+pte_leaflet_aligned(pte_t pte)
+{
+    struct ppage* ppfn = ppage(pfn(pte_paddr(pte)));
+    struct leaflet* _l = get_leaflet(ppfn);

 
 

-#define PG_ALIGN(addr) ((uintptr_t)(addr)&0xFFFFF000UL)
+    assert((ptr_t)_l == (ptr_t)ppfn);
+    return _l;
+}

 
 

-#define L1_INDEX(vaddr) (uint32_t)(((uintptr_t)(vaddr)&0xFFC00000UL) >> 22)
-#define L2_INDEX(vaddr) (uint32_t)(((uintptr_t)(vaddr)&0x003FF000UL) >> 12)
-#define PG_OFFSET(vaddr) (uint32_t)((uintptr_t)(vaddr)&0x00000FFFUL)
+static inline pfn_t
+leaflet_ppfn(struct leaflet* leaflet)
+{
+    return ppfn(get_ppage(leaflet));
+}

 
 

-#define GET_PT_ADDR(pde) PG_ALIGN(pde)
-#define GET_PG_ADDR(pte) PG_ALIGN(pte)
+static inline ptr_t
+leaflet_addr(struct leaflet* leaflet)
+{
+    return page_addr(ppfn(get_ppage(leaflet)));
+}
+
+static inline void
+unpin_leaflet(struct leaflet* leaflet)
+{
+    change_page_type(get_ppage(leaflet), 0);
+}
+
+static inline void
+pin_leaflet(struct leaflet* leaflet)
+{
+    change_page_type(get_ppage(leaflet), PP_FGLOCKED);
+}
+
+/**
+ * @brief Map a leaflet
+ * 
+ * @param ptep 
+ * @param leaflet 
+ * @return pages folded into that leaflet
+ */
+static inline size_t
+ptep_map_leaflet(pte_t* ptep, pte_t pte, struct leaflet* leaflet)
+{
+    // We do not support huge leaflet yet
+    assert(leaflet_order(leaflet) < LEVEL_SHIFT);

 
 

-#define PG_DIRTY(pte) ((pte & (1 << 6)) >> 6)
-#define PG_ACCESSED(pte) ((pte & (1 << 5)) >> 5)
+    pte = pte_setppfn(pte, leaflet_ppfn(leaflet));
+    pte = pte_mkloaded(pte);

 
 

-#define IS_CACHED(entry) ((entry & 0x1))
+    int n = leaflet_nfold(leaflet);
+    vmm_set_ptes_contig(ptep, pte, LFT_SIZE, n);

 
 

-#define PG_PRESENT (0x1)
-#define PG_WRITE (0x1 << 1)
-#define PG_ALLOW_USER (0x1 << 2)
-#define PG_WRITE_THROUGH (1 << 3)
-#define PG_DISABLE_CACHE (1 << 4)
-#define PG_PDE_4MB (1 << 7)
+    return n;
+}

 
 

-#define NEW_L1_ENTRY(flags, pt_addr)                                           \
-    (PG_ALIGN(pt_addr) | (((flags) | PG_WRITE_THROUGH) & 0xfff))
-#define NEW_L2_ENTRY(flags, pg_addr) (PG_ALIGN(pg_addr) | ((flags)&0xfff))
+/**
+ * @brief Unmap a leaflet
+ * 
+ * @param ptep 
+ * @param leaflet 
+ * @return pages folded into that leaflet
+ */
+static inline size_t
+ptep_unmap_leaflet(pte_t* ptep, struct leaflet* leaflet)
+{
+    // We do not support huge leaflet yet
+    assert(leaflet_order(leaflet) < LEVEL_SHIFT);

 
 

-#define V_ADDR(pd, pt, offset) ((pd) << 22 | (pt) << 12 | (offset))
-#define P_ADDR(ppn, offset) ((ppn << 12) | (offset))
+    int n = leaflet_nfold(leaflet);
+    vmm_unset_ptes(ptep, n);

 
 

-#define PG_ENTRY_FLAGS(entry) ((entry)&0xFFFU)
-#define PG_ENTRY_ADDR(entry) ((entry) & ~0xFFFU)
+    return n;
+}

 
 

-#define HAS_FLAGS(entry, flags) ((PG_ENTRY_FLAGS(entry) & (flags)) == flags)
-#define CONTAINS_FLAGS(entry, flags) (PG_ENTRY_FLAGS(entry) & (flags))
+static inline ptr_t
+leaflet_mount(struct leaflet* leaflet)
+{
+    pte_t* ptep = mkptep_va(VMS_SELF, PG_MOUNT_VAR);    
+    ptep_map_leaflet(ptep, mkpte_prot(KERNEL_DATA), leaflet);

 
 

-#define PG_PREM_R PG_PRESENT
-#define PG_PREM_RW PG_PRESENT | PG_WRITE
-#define PG_PREM_UR PG_PRESENT | PG_ALLOW_USER
-#define PG_PREM_URW PG_PRESENT | PG_WRITE | PG_ALLOW_USER
+    tlb_flush_kernel_ranged(PG_MOUNT_VAR, leaflet_nfold(leaflet));

 
 

-// 用于对PD进行循环映射，因为我们可能需要对PD进行频繁操作，我们在这里禁用TLB缓存
-#define T_SELF_REF_PERM PG_PREM_RW | PG_DISABLE_CACHE | PG_WRITE_THROUGH
+    return PG_MOUNT_VAR;
+}

 
 

-// 页目录的虚拟基地址，可以用来访问到各个PDE
-#define L1_BASE_VADDR 0xFFFFF000U
+static inline void
+leaflet_unmount(struct leaflet* leaflet)
+{
+    pte_t* ptep = mkptep_va(VMS_SELF, PG_MOUNT_VAR);    
+    vmm_unset_ptes(ptep, leaflet_nfold(leaflet));

 
 

-// 页表的虚拟基地址，可以用来访问到各个PTE
-#define L2_BASE_VADDR 0xFFC00000U
+    tlb_flush_kernel_ranged(PG_MOUNT_VAR, leaflet_nfold(leaflet));
+}

 
 

-// 用来获取特定的页表的虚拟地址
-#define L2_VADDR(pd_offset) (L2_BASE_VADDR | (pd_offset << 12))
+static inline void
+leaflet_fill(struct leaflet* leaflet, unsigned int val)
+{
+    ptr_t mnt;
+    
+    mnt = leaflet_mount(leaflet);
+    memset((void*)mnt, val, leaflet_size(leaflet));
+    leaflet_unmount(leaflet);
+}

 
 

-typedef unsigned long ptd_t;
-typedef unsigned long pt_t;
-typedef unsigned int pt_attr;
-typedef uint32_t x86_pte_t;
+static inline void
+leaflet_wipe(struct leaflet* leaflet)
+{
+    leaflet_fill(leaflet, 0);
+}

 
 /**
 
 /**

- * @brief 虚拟映射属性
+ * @brief Duplicate the leaflet

  *
  *

+ * @return Duplication of given leaflet
+ *
+ */
+struct leaflet*
+dup_leaflet(struct leaflet* leaflet);
+
+
+/**
+ * @brief Maps a number of contiguous ptes in kernel 
+ *        address space
+ * 
+ * @param pte the pte to be mapped
+ * @param lvl_size size of the page pointed by the given pte
+ * @param n number of ptes
+ * @return ptr_t 
+ */
+ptr_t
+vmap_ptes_at(pte_t pte, size_t lvl_size, int n);
+
+/**
+ * @brief Maps a number of contiguous ptes in kernel 
+ *        address space (leaf page size)
+ * 
+ * @param pte the pte to be mapped
+ * @param n number of ptes
+ * @return ptr_t 
+ */
+static inline ptr_t
+vmap_leaf_ptes(pte_t pte, int n)
+{
+    return vmap_ptes_at(pte, LFT_SIZE, n);
+}
+
+/**
+ * @brief Maps a contiguous range of physical address 
+ *        into kernel address space (leaf page size)
+ * 
+ * @param paddr start of the physical address range
+ * @param size size of the physical range
+ * @param prot default protection to be applied
+ * @return ptr_t 
+ */
+static inline ptr_t
+vmap(struct leaflet* leaflet, pte_attr_t prot)
+{
+    pte_t _pte = mkpte(page_addr(leaflet_ppfn(leaflet)), prot);
+    return vmap_ptes_at(_pte, LFT_SIZE, leaflet_nfold(leaflet));
+}
+
+void
+vunmap(ptr_t ptr, struct leaflet* leaflet);
+
+static inline ptr_t
+vmap_range(pfn_t start, size_t npages, pte_attr_t prot)
+{
+    pte_t _pte = mkpte(page_addr(start), prot);
+    return vmap_ptes_at(_pte, LFT_SIZE, npages);
+}
+
+static inline void
+vunmap_range(pfn_t start, size_t npages)
+{
+    pte_t* ptep = mkptep_va(VMS_SELF, start);
+    vmm_set_ptes_contig(ptep, null_pte, LFT_SIZE, npages);
+}
+
+
+/**
+ * @brief Allocate a page in kernel space.
+ * 
+ * @param ptep 
+ * @param pte 
+ * @param order 
+ * @return pte_t 

  */
  */

-typedef struct
-{
-    // 虚拟页地址
-    uintptr_t va;
-    // 物理页码（如果不存在映射，则为0）
-    uint32_t pn;
-    // 物理页地址（如果不存在映射，则为0）
-    uintptr_t pa;
-    // 映射的flags
-    uint16_t flags;
-    // PTE地址
-    x86_pte_t* pte;
-} v_mapping;
-
-typedef struct
-{
-    x86_pte_t entry[PG_MAX_ENTRIES];
-} __attribute__((packed)) x86_page_table;
-
-extern void __pg_mount_point;
-
-/* 四个页挂载点，两个页目录挂载点： 用于临时创建&编辑页表 */
-#define PG_MOUNT_RANGE(l1_index) (701 <= l1_index && l1_index <= 703)
-#define PD_MOUNT_1 (MMIO_BASE + MEM_4MB)
-#define PG_MOUNT_BASE (PD_MOUNT_1 + MEM_4MB)
-#define PG_MOUNT_1 (PG_MOUNT_BASE)
-#define PG_MOUNT_2 (PG_MOUNT_BASE + 0x1000)
-#define PG_MOUNT_3 (PG_MOUNT_BASE + 0x2000)
-#define PG_MOUNT_4 (PG_MOUNT_BASE + 0x3000)
-
-#define PD_REFERENCED L2_BASE_VADDR
-
-#define CURPROC_PTE(vpn)                                                       \
-    (&((x86_page_table*)(PD_MOUNT_1 | (((vpn)&0xffc00) << 2)))                 \
-        ->entry[(vpn)&0x3ff])
-#define PTE_MOUNTED(mnt, vpn)                                                  \
-    (((x86_page_table*)((mnt) | (((vpn)&0xffc00) << 2)))->entry[(vpn)&0x3ff])
+pte_t 
+alloc_kpage_at(pte_t* ptep, pte_t pte, int order);
+
+static inline void*
+vmalloc_page(int order)
+{
+    struct leaflet* leaf = alloc_leaflet(0);
+    if (!leaf) {
+        return NULL;
+    }
+
+    return (void*)vmap(leaf, KERNEL_DATA);
+}
+
+static inline void
+vmfree(void* ptr)
+{
+    struct leaflet* leaf = ppfn_leaflet(pfn((ptr_t)ptr));
+    leaflet_return(leaf);
+}

 
 #endif /* __LUNAIX_PAGE_H */
 
 #endif /* __LUNAIX_PAGE_H */