diff mbox series

[3/3] xen/ppc: mm-radix: Allocate Partition and Process Tables at runtime

Message ID b3943c96d4a97a87b6d79853de76d3775b093063.1701384928.git.sanastasio@raptorengineering.com (mailing list archive)
State Superseded
Headers show
Series Early Boot Allocation on Power | expand

Commit Message

Shawn Anastasio Dec. 1, 2023, 7:59 p.m. UTC
In the initial mm-radix implementation, the in-memory partition and
process tables required to configure the MMU were allocated statically
since the boot allocator was not yet available.

Now that it is, allocate these tables at runtime and bump the size of
the Process Table to its maximum supported value (on POWER9).

Signed-off-by: Shawn Anastasio <sanastasio@raptorengineering.com>
---
 xen/arch/ppc/mm-radix.c | 167 +++++++++++++++++++++++-----------------
 1 file changed, 96 insertions(+), 71 deletions(-)
diff mbox series

Patch

diff --git a/xen/arch/ppc/mm-radix.c b/xen/arch/ppc/mm-radix.c
index de181cf6f1..fae5ebfdcc 100644
--- a/xen/arch/ppc/mm-radix.c
+++ b/xen/arch/ppc/mm-radix.c
@@ -34,17 +34,13 @@  static struct lvl2_pd initial_lvl2_lvl3_pd_pool[INITIAL_LVL2_LVL3_PD_COUNT];
 static size_t __initdata initial_lvl4_pt_pool_used;
 static struct lvl4_pt initial_lvl4_pt_pool[INITIAL_LVL4_PT_COUNT];
 
-/* Only reserve minimum Partition and Process tables  */
 #define PATB_SIZE_LOG2 16 /* Only supported partition table size on POWER9 */
 #define PATB_SIZE      (1UL << PATB_SIZE_LOG2)
-#define PRTB_SIZE_LOG2 12
+#define PRTB_SIZE_LOG2 24 /* Maximum process table size on POWER9 */
 #define PRTB_SIZE      (1UL << PRTB_SIZE_LOG2)
 
-static struct patb_entry
-    __aligned(PATB_SIZE) initial_patb[PATB_SIZE / sizeof(struct patb_entry)];
-
-static struct prtb_entry
-    __aligned(PRTB_SIZE) initial_prtb[PRTB_SIZE / sizeof(struct prtb_entry)];
+static struct patb_entry *initial_patb;
+static struct prtb_entry *initial_prtb;
 
 static __init struct lvl1_pd *lvl1_pd_pool_alloc(void)
 {
@@ -86,6 +82,62 @@  static __init struct lvl4_pt *lvl4_pt_pool_alloc(void)
     return &initial_lvl4_pt_pool[initial_lvl4_pt_pool_used++];
 }
 
+static void map_page_initial(struct lvl1_pd *lvl1, vaddr_t virt, paddr_t phys,
+                             unsigned long flags)
+{
+    struct lvl2_pd *lvl2;
+    struct lvl3_pd *lvl3;
+    struct lvl4_pt *lvl4;
+    pde_t *pde;
+    pte_t *pte;
+
+    /* Allocate LVL 2 PD if necessary */
+    pde = pt_entry(lvl1, virt);
+    if ( !pde_is_valid(*pde) )
+    {
+        lvl2 = lvl2_pd_pool_alloc();
+        *pde = paddr_to_pde(__pa(lvl2), PDE_VALID,
+                            XEN_PT_ENTRIES_LOG2_LVL_2);
+    }
+    else
+        lvl2 = __va(pde_to_paddr(*pde));
+
+    /* Allocate LVL 3 PD if necessary */
+    pde = pt_entry(lvl2, virt);
+    if ( !pde_is_valid(*pde) )
+    {
+        lvl3 = lvl3_pd_pool_alloc();
+        *pde = paddr_to_pde(__pa(lvl3), PDE_VALID,
+                            XEN_PT_ENTRIES_LOG2_LVL_3);
+    }
+    else
+        lvl3 = __va(pde_to_paddr(*pde));
+
+    /* Allocate LVL 4 PT if necessary */
+    pde = pt_entry(lvl3, virt);
+    if ( !pde_is_valid(*pde) )
+    {
+        lvl4 = lvl4_pt_pool_alloc();
+        *pde = paddr_to_pde(__pa(lvl4), PDE_VALID,
+                            XEN_PT_ENTRIES_LOG2_LVL_4);
+    }
+    else
+        lvl4 = __va(pde_to_paddr(*pde));
+
+    /* Finally, create PTE in LVL 4 PT */
+    pte = pt_entry(lvl4, virt);
+    if ( !pte_is_valid(*pte) )
+    {
+        radix_dprintk("%016lx being mapped to %016lx\n", phys, virt);
+        *pte = paddr_to_pte(phys, flags);
+    }
+    else
+    {
+        early_printk("BUG: Tried to create PTE for already-mapped page!");
+        die();
+    }
+}
+
 static void __init setup_initial_mapping(struct lvl1_pd *lvl1,
                                          vaddr_t map_start,
                                          vaddr_t map_end,
@@ -105,80 +157,43 @@  static void __init setup_initial_mapping(struct lvl1_pd *lvl1,
         die();
     }
 
+    /* Identity map Xen itself */
     for ( page_addr = map_start; page_addr < map_end; page_addr += PAGE_SIZE )
     {
-        struct lvl2_pd *lvl2;
-        struct lvl3_pd *lvl3;
-        struct lvl4_pt *lvl4;
-        pde_t *pde;
-        pte_t *pte;
-
-        /* Allocate LVL 2 PD if necessary */
-        pde = pt_entry(lvl1, page_addr);
-        if ( !pde_is_valid(*pde) )
-        {
-            lvl2 = lvl2_pd_pool_alloc();
-            *pde = paddr_to_pde(__pa(lvl2), PDE_VALID,
-                                XEN_PT_ENTRIES_LOG2_LVL_2);
-        }
-        else
-            lvl2 = __va(pde_to_paddr(*pde));
+        unsigned long flags;
 
-        /* Allocate LVL 3 PD if necessary */
-        pde = pt_entry(lvl2, page_addr);
-        if ( !pde_is_valid(*pde) )
+        if ( is_kernel_text(page_addr) || is_kernel_inittext(page_addr) )
         {
-            lvl3 = lvl3_pd_pool_alloc();
-            *pde = paddr_to_pde(__pa(lvl3), PDE_VALID,
-                                XEN_PT_ENTRIES_LOG2_LVL_3);
+            radix_dprintk("%016lx being marked as TEXT (RX)\n", page_addr);
+            flags = PTE_XEN_RX;
         }
-        else
-            lvl3 = __va(pde_to_paddr(*pde));
-
-        /* Allocate LVL 4 PT if necessary */
-        pde = pt_entry(lvl3, page_addr);
-        if ( !pde_is_valid(*pde) )
-        {
-            lvl4 = lvl4_pt_pool_alloc();
-            *pde = paddr_to_pde(__pa(lvl4), PDE_VALID,
-                                XEN_PT_ENTRIES_LOG2_LVL_4);
-        }
-        else
-            lvl4 = __va(pde_to_paddr(*pde));
-
-        /* Finally, create PTE in LVL 4 PT */
-        pte = pt_entry(lvl4, page_addr);
-        if ( !pte_is_valid(*pte) )
+        else if ( is_kernel_rodata(page_addr) )
         {
-            unsigned long paddr = (page_addr - map_start) + phys_base;
-            unsigned long flags;
-
-            radix_dprintk("%016lx being mapped to %016lx\n", paddr, page_addr);
-            if ( is_kernel_text(page_addr) || is_kernel_inittext(page_addr) )
-            {
-                radix_dprintk("%016lx being marked as TEXT (RX)\n", page_addr);
-                flags = PTE_XEN_RX;
-            }
-            else if ( is_kernel_rodata(page_addr) )
-            {
-                radix_dprintk("%016lx being marked as RODATA (RO)\n", page_addr);
-                flags = PTE_XEN_RO;
-            }
-            else
-            {
-                radix_dprintk("%016lx being marked as DEFAULT (RW)\n", page_addr);
-                flags = PTE_XEN_RW;
-            }
-
-            *pte = paddr_to_pte(paddr, flags);
-            radix_dprintk("%016lx is the result of PTE map\n",
-                paddr_to_pte(paddr, flags).pte);
+            radix_dprintk("%016lx being marked as RODATA (RO)\n", page_addr);
+            flags = PTE_XEN_RO;
         }
         else
         {
-            early_printk("BUG: Tried to create PTE for already-mapped page!");
-            die();
+            radix_dprintk("%016lx being marked as DEFAULT (RW)\n", page_addr);
+            flags = PTE_XEN_RW;
         }
+
+        map_page_initial(lvl1, page_addr, (page_addr - map_start) + phys_base, flags);
+    }
+
+    /* Map runtime-allocated PATB, PRTB */
+    for ( page_addr = (uint64_t)initial_patb;
+          page_addr < (uint64_t)initial_patb + PATB_SIZE;
+          page_addr += PAGE_SIZE )
+    {
+        map_page_initial(lvl1, page_addr, __pa(page_addr), PTE_XEN_RW);
+    }
+
+    for ( page_addr = (uint64_t)initial_prtb;
+          page_addr < (uint64_t)initial_prtb + PRTB_SIZE;
+          page_addr += PAGE_SIZE )
+    {
+        map_page_initial(lvl1, page_addr, __pa(page_addr), PTE_XEN_RW);
     }
 }
 
@@ -210,6 +225,16 @@  void __init setup_initial_pagetables(void)
 {
     struct lvl1_pd *root = lvl1_pd_pool_alloc();
     unsigned long lpcr;
+    mfn_t patb_mfn, prtb_mfn;
+
+    /* Allocate mfns for in-memory tables using the boot allocator */
+    prtb_mfn = alloc_boot_pages(PRTB_SIZE / PAGE_SIZE,
+                                max(1, PRTB_SIZE_LOG2 - PAGE_SHIFT));
+    patb_mfn = alloc_boot_pages(PATB_SIZE / PAGE_SIZE,
+                                max(1, PATB_SIZE_LOG2 - PAGE_SHIFT));
+
+    initial_patb = __va(mfn_to_maddr(patb_mfn));
+    initial_prtb = __va(mfn_to_maddr(prtb_mfn));
 
     setup_initial_mapping(root, (vaddr_t)_start, (vaddr_t)_end, __pa(_start));