Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/arch/x86_64/ia32/syscall32.c b/arch/x86_64/ia32/syscall32.c
new file mode 100644
index 0000000..399ff49
--- /dev/null
+++ b/arch/x86_64/ia32/syscall32.c
@@ -0,0 +1,111 @@
+/* Copyright 2002,2003 Andi Kleen, SuSE Labs */
+
+/* vsyscall handling for 32bit processes. Map a stub page into it
+ on demand because 32bit cannot reach the kernel's fixmaps */
+
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/gfp.h>
+#include <linux/init.h>
+#include <linux/stringify.h>
+#include <asm/proto.h>
+#include <asm/tlbflush.h>
+#include <asm/ia32_unistd.h>
+
+/* 32bit VDSOs mapped into user space. */
+asm(".section \".init.data\",\"aw\"\n"
+ "syscall32_syscall:\n"
+ ".incbin \"arch/x86_64/ia32/vsyscall-syscall.so\"\n"
+ "syscall32_syscall_end:\n"
+ "syscall32_sysenter:\n"
+ ".incbin \"arch/x86_64/ia32/vsyscall-sysenter.so\"\n"
+ "syscall32_sysenter_end:\n"
+ ".previous");
+
+extern unsigned char syscall32_syscall[], syscall32_syscall_end[];
+extern unsigned char syscall32_sysenter[], syscall32_sysenter_end[];
+extern int sysctl_vsyscall32;
+
+char *syscall32_page;
+static int use_sysenter = -1;
+
+/*
+ * Map the 32bit vsyscall page on demand.
+ *
+ * RED-PEN: This knows too much about high level VM.
+ *
+ * Alternative would be to generate a vma with appropriate backing options
+ * and let it be handled by generic VM.
+ */
+int __map_syscall32(struct mm_struct *mm, unsigned long address)
+{
+ pgd_t *pgd;
+ pud_t *pud;
+ pte_t *pte;
+ pmd_t *pmd;
+ int err = -ENOMEM;
+
+ spin_lock(&mm->page_table_lock);
+ pgd = pgd_offset(mm, address);
+ pud = pud_alloc(mm, pgd, address);
+ if (pud) {
+ pmd = pmd_alloc(mm, pud, address);
+ if (pmd && (pte = pte_alloc_map(mm, pmd, address)) != NULL) {
+ if (pte_none(*pte)) {
+ set_pte(pte,
+ mk_pte(virt_to_page(syscall32_page),
+ PAGE_KERNEL_VSYSCALL32));
+ }
+ /* Flush only the local CPU. Other CPUs taking a fault
+ will just end up here again
+ This probably not needed and just paranoia. */
+ __flush_tlb_one(address);
+ err = 0;
+ }
+ }
+ spin_unlock(&mm->page_table_lock);
+ return err;
+}
+
+int map_syscall32(struct mm_struct *mm, unsigned long address)
+{
+ int err;
+ down_read(&mm->mmap_sem);
+ err = __map_syscall32(mm, address);
+ up_read(&mm->mmap_sem);
+ return err;
+}
+
+static int __init init_syscall32(void)
+{
+ syscall32_page = (void *)get_zeroed_page(GFP_KERNEL);
+ if (!syscall32_page)
+ panic("Cannot allocate syscall32 page");
+ SetPageReserved(virt_to_page(syscall32_page));
+ if (use_sysenter > 0) {
+ memcpy(syscall32_page, syscall32_sysenter,
+ syscall32_sysenter_end - syscall32_sysenter);
+ } else {
+ memcpy(syscall32_page, syscall32_syscall,
+ syscall32_syscall_end - syscall32_syscall);
+ }
+ return 0;
+}
+
+__initcall(init_syscall32);
+
+/* May not be __init: called during resume */
+void syscall32_cpu_init(void)
+{
+ if (use_sysenter < 0)
+ use_sysenter = (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL);
+
+ /* Load these always in case some future AMD CPU supports
+ SYSENTER from compat mode too. */
+ checking_wrmsrl(MSR_IA32_SYSENTER_CS, (u64)__KERNEL_CS);
+ checking_wrmsrl(MSR_IA32_SYSENTER_ESP, 0ULL);
+ checking_wrmsrl(MSR_IA32_SYSENTER_EIP, (u64)ia32_sysenter_target);
+
+ wrmsrl(MSR_CSTAR, ia32_cstar_target);
+}