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-rw-r--r--arch/x86/mm/pgtable_32.c104
1 files changed, 104 insertions, 0 deletions
diff --git a/arch/x86/mm/pgtable_32.c b/arch/x86/mm/pgtable_32.c
new file mode 100644
index 0000000000..c234634e26
--- /dev/null
+++ b/arch/x86/mm/pgtable_32.c
@@ -0,0 +1,104 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/nmi.h>
+#include <linux/swap.h>
+#include <linux/smp.h>
+#include <linux/highmem.h>
+#include <linux/pagemap.h>
+#include <linux/spinlock.h>
+
+#include <asm/cpu_entry_area.h>
+#include <asm/fixmap.h>
+#include <asm/e820/api.h>
+#include <asm/tlb.h>
+#include <asm/tlbflush.h>
+#include <asm/io.h>
+#include <linux/vmalloc.h>
+
+unsigned int __VMALLOC_RESERVE = 128 << 20;
+
+/*
+ * Associate a virtual page frame with a given physical page frame
+ * and protection flags for that frame.
+ */
+void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
+{
+ pgd_t *pgd;
+ p4d_t *p4d;
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte;
+
+ pgd = swapper_pg_dir + pgd_index(vaddr);
+ if (pgd_none(*pgd)) {
+ BUG();
+ return;
+ }
+ p4d = p4d_offset(pgd, vaddr);
+ if (p4d_none(*p4d)) {
+ BUG();
+ return;
+ }
+ pud = pud_offset(p4d, vaddr);
+ if (pud_none(*pud)) {
+ BUG();
+ return;
+ }
+ pmd = pmd_offset(pud, vaddr);
+ if (pmd_none(*pmd)) {
+ BUG();
+ return;
+ }
+ pte = pte_offset_kernel(pmd, vaddr);
+ if (!pte_none(pteval))
+ set_pte_at(&init_mm, vaddr, pte, pteval);
+ else
+ pte_clear(&init_mm, vaddr, pte);
+
+ /*
+ * It's enough to flush this one mapping.
+ * (PGE mappings get flushed as well)
+ */
+ flush_tlb_one_kernel(vaddr);
+}
+
+unsigned long __FIXADDR_TOP = 0xfffff000;
+EXPORT_SYMBOL(__FIXADDR_TOP);
+
+/*
+ * vmalloc=size forces the vmalloc area to be exactly 'size'
+ * bytes. This can be used to increase (or decrease) the
+ * vmalloc area - the default is 128m.
+ */
+static int __init parse_vmalloc(char *arg)
+{
+ if (!arg)
+ return -EINVAL;
+
+ /* Add VMALLOC_OFFSET to the parsed value due to vm area guard hole*/
+ __VMALLOC_RESERVE = memparse(arg, &arg) + VMALLOC_OFFSET;
+ return 0;
+}
+early_param("vmalloc", parse_vmalloc);
+
+/*
+ * reservetop=size reserves a hole at the top of the kernel address space which
+ * a hypervisor can load into later. Needed for dynamically loaded hypervisors,
+ * so relocating the fixmap can be done before paging initialization.
+ */
+static int __init parse_reservetop(char *arg)
+{
+ unsigned long address;
+
+ if (!arg)
+ return -EINVAL;
+
+ address = memparse(arg, &arg);
+ reserve_top_address(address);
+ early_ioremap_init();
+ return 0;
+}
+early_param("reservetop", parse_reservetop);