arch,pt: add support for global page table entries

Signed-off-by: Pawel Wieczorkiewicz <[email protected]>
KernelTestFramework · Nov 21, 2023 · 56b84a1 · 56b84a1
1 parent 43b2ae9
commit 56b84a1
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Showing 12 changed files with 36 additions and 22 deletions.
diff --git a/arch/x86/apic.c b/arch/x86/apic.c
@@ -160,7 +160,7 @@ void init_apic(unsigned int cpu_id, apic_mode_t mode) {
      * X2APIC uses MSRs for accesses, so no mapping needed.
      */
     if (apic_mode == APIC_MODE_XAPIC)
-        vmap_4k(apic_get_base(apic_base), apic_base.base, L1_PROT_NOCACHE);
+        vmap_4k(apic_get_base(apic_base), apic_base.base, L1_PROT_NOCACHE_GLOB);
 
     spiv.reg = apic_read(APIC_SPIV);
     spiv.vector = APIC_SPI_VECTOR;

diff --git a/arch/x86/pagetables.c b/arch/x86/pagetables.c
@@ -349,7 +349,7 @@ static void map_tmp_mapping_entry(void) {
     pte_t *entry = l1_table_entry(mfn_to_virt(l1e->mfn), _tmp_mapping);
 
     /* Map _tmp_mapping_entry PTE of new page tables */
-    kmap_4k(l1e->mfn, L1_PROT);
+    kmap_4k(l1e->mfn, L1_PROT_GLOB);
 
     /* Point _tmp_mapping_entry at new page tables location */
     _tmp_mapping_entry = paddr_to_virt_kern(_paddr(entry));
@@ -812,5 +812,6 @@ void init_pagetables(void) {
     map_multiboot_areas();
     map_tmp_mapping_entry();
 
+    setup_tlb_global();
     write_cr3(cr3.paddr);
 }
diff --git a/common/cmdline.c b/common/cmdline.c
@@ -76,6 +76,9 @@ bool_cmd("fb_scroll", opt_fb_scroll);
 unsigned long opt_reboot_timeout = 0; /* Disabled by default */
 ulong_cmd("reboot_timeout", opt_reboot_timeout);
 
+bool opt_tlb_global = true;
+bool_cmd("tlb_global", opt_tlb_global);
+
 const char *kernel_cmdline;
 
 void __text_init cmdline_parse(const char *cmdline) {

diff --git a/common/usermode.c b/common/usermode.c
@@ -107,17 +107,17 @@ static void init_sysenter(percpu_t *percpu) {
 }
 
 void init_usermode(percpu_t *percpu) {
-    vmap_user_4k(&cr3, virt_to_mfn(&cr3), L1_PROT);
+    vmap_user_4k(&cr3, virt_to_mfn(&cr3), L1_PROT_GLOB);
     vmap_user_4k(&user_cr3, virt_to_mfn(&user_cr3), L1_PROT);
 
     BUG_ON(end_exception_handlers - exception_handlers > (long) PAGE_SIZE);
-    vmap_user_4k(exception_handlers, virt_to_mfn(exception_handlers), L1_PROT);
+    vmap_user_4k(exception_handlers, virt_to_mfn(exception_handlers), L1_PROT_RO_GLOB);
 
     BUG_ON(end_interrupt_handlers - interrupt_handlers > (long) PAGE_SIZE);
-    vmap_user_4k(interrupt_handlers, virt_to_mfn(interrupt_handlers), L1_PROT);
+    vmap_user_4k(interrupt_handlers, virt_to_mfn(interrupt_handlers), L1_PROT_RO_GLOB);
 
     BUG_ON(end_usermode_helpers - usermode_helpers > (long) PAGE_SIZE);
-    vmap_user_4k(usermode_helpers, virt_to_mfn(usermode_helpers), L1_PROT);
+    vmap_user_4k(usermode_helpers, virt_to_mfn(usermode_helpers), L1_PROT_RO_GLOB);
 
     init_syscall();
     init_sysenter(percpu);

diff --git a/drivers/fb/fb.c b/drivers/fb/fb.c
@@ -56,8 +56,8 @@ static void (*put_pixel)(uint32_t x, uint32_t y, uint32_t color);
 static void map_fb_area(paddr_t start, size_t size) {
     for (mfn_t video_mfn = paddr_to_mfn(start); video_mfn < paddr_to_mfn(start + size);
          video_mfn++) {
-        vmap_4k(mfn_to_virt(video_mfn), video_mfn, L1_PROT_NOCACHE);
-        kmap_4k(video_mfn, L1_PROT_NOCACHE);
+        vmap_4k(mfn_to_virt(video_mfn), video_mfn, L1_PROT_NOCACHE_GLOB);
+        kmap_4k(video_mfn, L1_PROT_NOCACHE_GLOB);
     }
 }
 

diff --git a/drivers/hpet.c b/drivers/hpet.c
@@ -59,7 +59,7 @@ bool init_hpet(const cpu_t *cpu) {
 #endif
 
     hpet_base_mfn = paddr_to_mfn(address);
-    vmap_4k(_ptr(address), hpet_base_mfn, L1_PROT_NOCACHE);
+    vmap_4k(_ptr(address), hpet_base_mfn, L1_PROT_NOCACHE_GLOB);
     config = (acpi_hpet_timer_t *) (address + HPET_OFFSET_TIMER_0_CONFIG_CAP_REG);
     general = (acpi_hpet_general_t *) (address + HPET_OFFSET_GENERAL_CAP_REG);
     main_counter = (uint64_t *) (address + HPET_OFFSET_GENERAL_MAIN_COUNTER_REG);

diff --git a/drivers/vga.c b/drivers/vga.c
@@ -83,7 +83,7 @@ void vga_write(void *vga_memory, const char *buf, size_t len, vga_color_t color)
 void map_vga_area(void) {
     for (mfn_t vga_mfn = paddr_to_mfn(VGA_START_ADDR);
          vga_mfn < paddr_to_mfn(VGA_END_ADDR); vga_mfn++) {
-        vmap_4k(mfn_to_virt(vga_mfn), vga_mfn, L1_PROT_NOCACHE);
-        kmap_4k(vga_mfn, L1_PROT_NOCACHE);
+        vmap_4k(mfn_to_virt(vga_mfn), vga_mfn, L1_PROT_NOCACHE_GLOB);
+        kmap_4k(vga_mfn, L1_PROT_NOCACHE_GLOB);
     }
 }
diff --git a/include/arch/x86/page.h b/include/arch/x86/page.h
@@ -70,11 +70,14 @@
 
 #define PT_NO_FLAGS 0
 
-#define L1_PROT         (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
-#define L1_PROT_RO      (_PAGE_PRESENT | _PAGE_ACCESSED)
-#define L1_PROT_NOCACHE (L1_PROT | _PAGE_PCD)
-#define L1_PROT_USER    (L1_PROT | _PAGE_USER)
-#define L1_PROT_USER_RO (L1_PROT_RO | _PAGE_USER)
+#define L1_PROT              (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
+#define L1_PROT_GLOB         (L1_PROT | _PAGE_GLOBAL)
+#define L1_PROT_RO           (_PAGE_PRESENT | _PAGE_ACCESSED)
+#define L1_PROT_RO_GLOB      (L1_PROT_RO | _PAGE_GLOBAL)
+#define L1_PROT_NOCACHE      (L1_PROT | _PAGE_PCD)
+#define L1_PROT_NOCACHE_GLOB (L1_PROT_NOCACHE | _PAGE_GLOBAL)
+#define L1_PROT_USER         (L1_PROT | _PAGE_USER)
+#define L1_PROT_USER_RO      (L1_PROT_RO | _PAGE_USER)
 
 #define L2_PROT         (L1_PROT | _PAGE_DIRTY)
 #define L2_PROT_RO      (L1_PROT_RO | _PAGE_DIRTY)

diff --git a/include/arch/x86/pagetable.h b/include/arch/x86/pagetable.h
@@ -292,6 +292,11 @@ static inline bool is_pgentry_present(pgentry_t e) {
     return !!(e & _PAGE_PRESENT);
 }
 
+static inline void setup_tlb_global(void) {
+    unsigned long cr4 = read_cr4();
+    write_cr4(opt_tlb_global ? (cr4 | X86_CR4_PGE) : (cr4 & ~X86_CR4_PGE));
+}
+
 /* External declarations */
 
 extern pte_t l1_pt_entries1[L1_PT_ENTRIES];

diff --git a/include/cmdline.h b/include/cmdline.h
@@ -69,6 +69,7 @@ extern bool opt_qemu_console;
 extern bool opt_poweroff;
 extern bool opt_fb_scroll;
 extern unsigned long opt_reboot_timeout;
+extern bool opt_tlb_global;
 
 extern const char *kernel_cmdline;
 

diff --git a/mm/regions.c b/mm/regions.c
@@ -59,12 +59,12 @@ addr_range_t addr_ranges[] = {
     USER_RANGE( ".data.user",   L1_PROT_USER,    __start_data_user,     __end_data_user ),
     USER_RANGE( ".bss.user",    L1_PROT_USER,    __start_bss_user,      __end_bss_user  ),
 
-    KERNEL_RANGE( ".text",      L1_PROT_RO,      __start_text,           __end_text     ),
-    KERNEL_RANGE( ".data",      L1_PROT,         __start_data,           __end_data     ),
-    KERNEL_RANGE( ".extables",  L1_PROT_RO,      __start_extables,       __end_extables ),
-    KERNEL_RANGE( ".bss",       L1_PROT,         __start_bss,            __end_bss      ),
-    KERNEL_RANGE( ".rodata",    L1_PROT_RO,      __start_rodata,         __end_rodata   ),
-    KERNEL_RANGE( ".symbols",   L1_PROT_RO,      __start_symbols,        __end_symbols  ),
+    KERNEL_RANGE( ".text",      L1_PROT_RO_GLOB, __start_text,          __end_text      ),
+    KERNEL_RANGE( ".data",      L1_PROT_GLOB,    __start_data,          __end_data      ),
+    KERNEL_RANGE( ".bss",       L1_PROT_GLOB,    __start_bss,           __end_bss       ),
+    KERNEL_RANGE( ".rodata",    L1_PROT_RO,      __start_rodata,        __end_rodata    ),
+    KERNEL_RANGE( ".extables",  L1_PROT_RO_GLOB, __start_extables,      __end_extables  ),
+    KERNEL_RANGE( ".symbols",   L1_PROT_RO,      __start_symbols,       __end_symbols   ),
     /* clang-format on */
 
     {0x0} /* NULL array terminator */

diff --git a/smp/smp.c b/smp/smp.c
@@ -50,6 +50,7 @@ cr3_t __data_init ap_cr3;
 
 void __noreturn ap_startup(void) {
     WRITE_SP(ap_new_sp);
+    setup_tlb_global();
 
     cpu_t *cpu = get_cpu(ap_cpuid);