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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/x86/include/asm/desc.h
Initial import
Diffstat (limited to 'arch/x86/include/asm/desc.h')
-rw-r--r--arch/x86/include/asm/desc.h519
1 files changed, 519 insertions, 0 deletions
diff --git a/arch/x86/include/asm/desc.h b/arch/x86/include/asm/desc.h
new file mode 100644
index 000000000..a0bf89fd2
--- /dev/null
+++ b/arch/x86/include/asm/desc.h
@@ -0,0 +1,519 @@
+#ifndef _ASM_X86_DESC_H
+#define _ASM_X86_DESC_H
+
+#include <asm/desc_defs.h>
+#include <asm/ldt.h>
+#include <asm/mmu.h>
+
+#include <linux/smp.h>
+#include <linux/percpu.h>
+
+static inline void fill_ldt(struct desc_struct *desc, const struct user_desc *info)
+{
+ desc->limit0 = info->limit & 0x0ffff;
+
+ desc->base0 = (info->base_addr & 0x0000ffff);
+ desc->base1 = (info->base_addr & 0x00ff0000) >> 16;
+
+ desc->type = (info->read_exec_only ^ 1) << 1;
+ desc->type |= info->contents << 2;
+
+ desc->s = 1;
+ desc->dpl = 0x3;
+ desc->p = info->seg_not_present ^ 1;
+ desc->limit = (info->limit & 0xf0000) >> 16;
+ desc->avl = info->useable;
+ desc->d = info->seg_32bit;
+ desc->g = info->limit_in_pages;
+
+ desc->base2 = (info->base_addr & 0xff000000) >> 24;
+ /*
+ * Don't allow setting of the lm bit. It would confuse
+ * user_64bit_mode and would get overridden by sysret anyway.
+ */
+ desc->l = 0;
+}
+
+extern struct desc_ptr idt_descr;
+extern gate_desc idt_table[];
+extern struct desc_ptr debug_idt_descr;
+extern gate_desc debug_idt_table[];
+
+struct gdt_page {
+ struct desc_struct gdt[GDT_ENTRIES];
+} __attribute__((aligned(PAGE_SIZE)));
+
+DECLARE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page);
+
+static inline struct desc_struct *get_cpu_gdt_table(unsigned int cpu)
+{
+ return per_cpu(gdt_page, cpu).gdt;
+}
+
+#ifdef CONFIG_X86_64
+
+static inline void pack_gate(gate_desc *gate, unsigned type, unsigned long func,
+ unsigned dpl, unsigned ist, unsigned seg)
+{
+ gate->offset_low = PTR_LOW(func);
+ gate->segment = __KERNEL_CS;
+ gate->ist = ist;
+ gate->p = 1;
+ gate->dpl = dpl;
+ gate->zero0 = 0;
+ gate->zero1 = 0;
+ gate->type = type;
+ gate->offset_middle = PTR_MIDDLE(func);
+ gate->offset_high = PTR_HIGH(func);
+}
+
+#else
+static inline void pack_gate(gate_desc *gate, unsigned char type,
+ unsigned long base, unsigned dpl, unsigned flags,
+ unsigned short seg)
+{
+ gate->a = (seg << 16) | (base & 0xffff);
+ gate->b = (base & 0xffff0000) | (((0x80 | type | (dpl << 5)) & 0xff) << 8);
+}
+
+#endif
+
+static inline int desc_empty(const void *ptr)
+{
+ const u32 *desc = ptr;
+
+ return !(desc[0] | desc[1]);
+}
+
+#ifdef CONFIG_PARAVIRT
+#include <asm/paravirt.h>
+#else
+#define load_TR_desc() native_load_tr_desc()
+#define load_gdt(dtr) native_load_gdt(dtr)
+#define load_idt(dtr) native_load_idt(dtr)
+#define load_tr(tr) asm volatile("ltr %0"::"m" (tr))
+#define load_ldt(ldt) asm volatile("lldt %0"::"m" (ldt))
+
+#define store_gdt(dtr) native_store_gdt(dtr)
+#define store_idt(dtr) native_store_idt(dtr)
+#define store_tr(tr) (tr = native_store_tr())
+
+#define load_TLS(t, cpu) native_load_tls(t, cpu)
+#define set_ldt native_set_ldt
+
+#define write_ldt_entry(dt, entry, desc) native_write_ldt_entry(dt, entry, desc)
+#define write_gdt_entry(dt, entry, desc, type) native_write_gdt_entry(dt, entry, desc, type)
+#define write_idt_entry(dt, entry, g) native_write_idt_entry(dt, entry, g)
+
+static inline void paravirt_alloc_ldt(struct desc_struct *ldt, unsigned entries)
+{
+}
+
+static inline void paravirt_free_ldt(struct desc_struct *ldt, unsigned entries)
+{
+}
+#endif /* CONFIG_PARAVIRT */
+
+#define store_ldt(ldt) asm("sldt %0" : "=m"(ldt))
+
+static inline void native_write_idt_entry(gate_desc *idt, int entry, const gate_desc *gate)
+{
+ memcpy(&idt[entry], gate, sizeof(*gate));
+}
+
+static inline void native_write_ldt_entry(struct desc_struct *ldt, int entry, const void *desc)
+{
+ memcpy(&ldt[entry], desc, 8);
+}
+
+static inline void
+native_write_gdt_entry(struct desc_struct *gdt, int entry, const void *desc, int type)
+{
+ unsigned int size;
+
+ switch (type) {
+ case DESC_TSS: size = sizeof(tss_desc); break;
+ case DESC_LDT: size = sizeof(ldt_desc); break;
+ default: size = sizeof(*gdt); break;
+ }
+
+ memcpy(&gdt[entry], desc, size);
+}
+
+static inline void pack_descriptor(struct desc_struct *desc, unsigned long base,
+ unsigned long limit, unsigned char type,
+ unsigned char flags)
+{
+ desc->a = ((base & 0xffff) << 16) | (limit & 0xffff);
+ desc->b = (base & 0xff000000) | ((base & 0xff0000) >> 16) |
+ (limit & 0x000f0000) | ((type & 0xff) << 8) |
+ ((flags & 0xf) << 20);
+ desc->p = 1;
+}
+
+
+static inline void set_tssldt_descriptor(void *d, unsigned long addr, unsigned type, unsigned size)
+{
+#ifdef CONFIG_X86_64
+ struct ldttss_desc64 *desc = d;
+
+ memset(desc, 0, sizeof(*desc));
+
+ desc->limit0 = size & 0xFFFF;
+ desc->base0 = PTR_LOW(addr);
+ desc->base1 = PTR_MIDDLE(addr) & 0xFF;
+ desc->type = type;
+ desc->p = 1;
+ desc->limit1 = (size >> 16) & 0xF;
+ desc->base2 = (PTR_MIDDLE(addr) >> 8) & 0xFF;
+ desc->base3 = PTR_HIGH(addr);
+#else
+ pack_descriptor((struct desc_struct *)d, addr, size, 0x80 | type, 0);
+#endif
+}
+
+static inline void __set_tss_desc(unsigned cpu, unsigned int entry, void *addr)
+{
+ struct desc_struct *d = get_cpu_gdt_table(cpu);
+ tss_desc tss;
+
+ /*
+ * sizeof(unsigned long) coming from an extra "long" at the end
+ * of the iobitmap. See tss_struct definition in processor.h
+ *
+ * -1? seg base+limit should be pointing to the address of the
+ * last valid byte
+ */
+ set_tssldt_descriptor(&tss, (unsigned long)addr, DESC_TSS,
+ IO_BITMAP_OFFSET + IO_BITMAP_BYTES +
+ sizeof(unsigned long) - 1);
+ write_gdt_entry(d, entry, &tss, DESC_TSS);
+}
+
+#define set_tss_desc(cpu, addr) __set_tss_desc(cpu, GDT_ENTRY_TSS, addr)
+
+static inline void native_set_ldt(const void *addr, unsigned int entries)
+{
+ if (likely(entries == 0))
+ asm volatile("lldt %w0"::"q" (0));
+ else {
+ unsigned cpu = smp_processor_id();
+ ldt_desc ldt;
+
+ set_tssldt_descriptor(&ldt, (unsigned long)addr, DESC_LDT,
+ entries * LDT_ENTRY_SIZE - 1);
+ write_gdt_entry(get_cpu_gdt_table(cpu), GDT_ENTRY_LDT,
+ &ldt, DESC_LDT);
+ asm volatile("lldt %w0"::"q" (GDT_ENTRY_LDT*8));
+ }
+}
+
+static inline void native_load_tr_desc(void)
+{
+ asm volatile("ltr %w0"::"q" (GDT_ENTRY_TSS*8));
+}
+
+static inline void native_load_gdt(const struct desc_ptr *dtr)
+{
+ asm volatile("lgdt %0"::"m" (*dtr));
+}
+
+static inline void native_load_idt(const struct desc_ptr *dtr)
+{
+ asm volatile("lidt %0"::"m" (*dtr));
+}
+
+static inline void native_store_gdt(struct desc_ptr *dtr)
+{
+ asm volatile("sgdt %0":"=m" (*dtr));
+}
+
+static inline void native_store_idt(struct desc_ptr *dtr)
+{
+ asm volatile("sidt %0":"=m" (*dtr));
+}
+
+static inline unsigned long native_store_tr(void)
+{
+ unsigned long tr;
+
+ asm volatile("str %0":"=r" (tr));
+
+ return tr;
+}
+
+static inline void native_load_tls(struct thread_struct *t, unsigned int cpu)
+{
+ struct desc_struct *gdt = get_cpu_gdt_table(cpu);
+ unsigned int i;
+
+ for (i = 0; i < GDT_ENTRY_TLS_ENTRIES; i++)
+ gdt[GDT_ENTRY_TLS_MIN + i] = t->tls_array[i];
+}
+
+/* This intentionally ignores lm, since 32-bit apps don't have that field. */
+#define LDT_empty(info) \
+ ((info)->base_addr == 0 && \
+ (info)->limit == 0 && \
+ (info)->contents == 0 && \
+ (info)->read_exec_only == 1 && \
+ (info)->seg_32bit == 0 && \
+ (info)->limit_in_pages == 0 && \
+ (info)->seg_not_present == 1 && \
+ (info)->useable == 0)
+
+/* Lots of programs expect an all-zero user_desc to mean "no segment at all". */
+static inline bool LDT_zero(const struct user_desc *info)
+{
+ return (info->base_addr == 0 &&
+ info->limit == 0 &&
+ info->contents == 0 &&
+ info->read_exec_only == 0 &&
+ info->seg_32bit == 0 &&
+ info->limit_in_pages == 0 &&
+ info->seg_not_present == 0 &&
+ info->useable == 0);
+}
+
+static inline void clear_LDT(void)
+{
+ set_ldt(NULL, 0);
+}
+
+/*
+ * load one particular LDT into the current CPU
+ */
+static inline void load_LDT_nolock(mm_context_t *pc)
+{
+ set_ldt(pc->ldt, pc->size);
+}
+
+static inline void load_LDT(mm_context_t *pc)
+{
+ preempt_disable();
+ load_LDT_nolock(pc);
+ preempt_enable();
+}
+
+static inline unsigned long get_desc_base(const struct desc_struct *desc)
+{
+ return (unsigned)(desc->base0 | ((desc->base1) << 16) | ((desc->base2) << 24));
+}
+
+static inline void set_desc_base(struct desc_struct *desc, unsigned long base)
+{
+ desc->base0 = base & 0xffff;
+ desc->base1 = (base >> 16) & 0xff;
+ desc->base2 = (base >> 24) & 0xff;
+}
+
+static inline unsigned long get_desc_limit(const struct desc_struct *desc)
+{
+ return desc->limit0 | (desc->limit << 16);
+}
+
+static inline void set_desc_limit(struct desc_struct *desc, unsigned long limit)
+{
+ desc->limit0 = limit & 0xffff;
+ desc->limit = (limit >> 16) & 0xf;
+}
+
+#ifdef CONFIG_X86_64
+static inline void set_nmi_gate(int gate, void *addr)
+{
+ gate_desc s;
+
+ pack_gate(&s, GATE_INTERRUPT, (unsigned long)addr, 0, 0, __KERNEL_CS);
+ write_idt_entry(debug_idt_table, gate, &s);
+}
+#endif
+
+#ifdef CONFIG_TRACING
+extern struct desc_ptr trace_idt_descr;
+extern gate_desc trace_idt_table[];
+static inline void write_trace_idt_entry(int entry, const gate_desc *gate)
+{
+ write_idt_entry(trace_idt_table, entry, gate);
+}
+
+static inline void _trace_set_gate(int gate, unsigned type, void *addr,
+ unsigned dpl, unsigned ist, unsigned seg)
+{
+ gate_desc s;
+
+ pack_gate(&s, type, (unsigned long)addr, dpl, ist, seg);
+ /*
+ * does not need to be atomic because it is only done once at
+ * setup time
+ */
+ write_trace_idt_entry(gate, &s);
+}
+#else
+static inline void write_trace_idt_entry(int entry, const gate_desc *gate)
+{
+}
+
+#define _trace_set_gate(gate, type, addr, dpl, ist, seg)
+#endif
+
+static inline void _set_gate(int gate, unsigned type, void *addr,
+ unsigned dpl, unsigned ist, unsigned seg)
+{
+ gate_desc s;
+
+ pack_gate(&s, type, (unsigned long)addr, dpl, ist, seg);
+ /*
+ * does not need to be atomic because it is only done once at
+ * setup time
+ */
+ write_idt_entry(idt_table, gate, &s);
+ write_trace_idt_entry(gate, &s);
+}
+
+/*
+ * This needs to use 'idt_table' rather than 'idt', and
+ * thus use the _nonmapped_ version of the IDT, as the
+ * Pentium F0 0F bugfix can have resulted in the mapped
+ * IDT being write-protected.
+ */
+#define set_intr_gate_notrace(n, addr) \
+ do { \
+ BUG_ON((unsigned)n > 0xFF); \
+ _set_gate(n, GATE_INTERRUPT, (void *)addr, 0, 0, \
+ __KERNEL_CS); \
+ } while (0)
+
+#define set_intr_gate(n, addr) \
+ do { \
+ set_intr_gate_notrace(n, addr); \
+ _trace_set_gate(n, GATE_INTERRUPT, (void *)trace_##addr,\
+ 0, 0, __KERNEL_CS); \
+ } while (0)
+
+extern int first_system_vector;
+/* used_vectors is BITMAP for irq is not managed by percpu vector_irq */
+extern unsigned long used_vectors[];
+
+static inline void alloc_system_vector(int vector)
+{
+ if (!test_bit(vector, used_vectors)) {
+ set_bit(vector, used_vectors);
+ if (first_system_vector > vector)
+ first_system_vector = vector;
+ } else {
+ BUG();
+ }
+}
+
+#define alloc_intr_gate(n, addr) \
+ do { \
+ alloc_system_vector(n); \
+ set_intr_gate(n, addr); \
+ } while (0)
+
+/*
+ * This routine sets up an interrupt gate at directory privilege level 3.
+ */
+static inline void set_system_intr_gate(unsigned int n, void *addr)
+{
+ BUG_ON((unsigned)n > 0xFF);
+ _set_gate(n, GATE_INTERRUPT, addr, 0x3, 0, __KERNEL_CS);
+}
+
+static inline void set_system_trap_gate(unsigned int n, void *addr)
+{
+ BUG_ON((unsigned)n > 0xFF);
+ _set_gate(n, GATE_TRAP, addr, 0x3, 0, __KERNEL_CS);
+}
+
+static inline void set_trap_gate(unsigned int n, void *addr)
+{
+ BUG_ON((unsigned)n > 0xFF);
+ _set_gate(n, GATE_TRAP, addr, 0, 0, __KERNEL_CS);
+}
+
+static inline void set_task_gate(unsigned int n, unsigned int gdt_entry)
+{
+ BUG_ON((unsigned)n > 0xFF);
+ _set_gate(n, GATE_TASK, (void *)0, 0, 0, (gdt_entry<<3));
+}
+
+static inline void set_intr_gate_ist(int n, void *addr, unsigned ist)
+{
+ BUG_ON((unsigned)n > 0xFF);
+ _set_gate(n, GATE_INTERRUPT, addr, 0, ist, __KERNEL_CS);
+}
+
+static inline void set_system_intr_gate_ist(int n, void *addr, unsigned ist)
+{
+ BUG_ON((unsigned)n > 0xFF);
+ _set_gate(n, GATE_INTERRUPT, addr, 0x3, ist, __KERNEL_CS);
+}
+
+#ifdef CONFIG_X86_64
+DECLARE_PER_CPU(u32, debug_idt_ctr);
+static inline bool is_debug_idt_enabled(void)
+{
+ if (this_cpu_read(debug_idt_ctr))
+ return true;
+
+ return false;
+}
+
+static inline void load_debug_idt(void)
+{
+ load_idt((const struct desc_ptr *)&debug_idt_descr);
+}
+#else
+static inline bool is_debug_idt_enabled(void)
+{
+ return false;
+}
+
+static inline void load_debug_idt(void)
+{
+}
+#endif
+
+#ifdef CONFIG_TRACING
+extern atomic_t trace_idt_ctr;
+static inline bool is_trace_idt_enabled(void)
+{
+ if (atomic_read(&trace_idt_ctr))
+ return true;
+
+ return false;
+}
+
+static inline void load_trace_idt(void)
+{
+ load_idt((const struct desc_ptr *)&trace_idt_descr);
+}
+#else
+static inline bool is_trace_idt_enabled(void)
+{
+ return false;
+}
+
+static inline void load_trace_idt(void)
+{
+}
+#endif
+
+/*
+ * The load_current_idt() must be called with interrupts disabled
+ * to avoid races. That way the IDT will always be set back to the expected
+ * descriptor. It's also called when a CPU is being initialized, and
+ * that doesn't need to disable interrupts, as nothing should be
+ * bothering the CPU then.
+ */
+static inline void load_current_idt(void)
+{
+ if (is_debug_idt_enabled())
+ load_debug_idt();
+ else if (is_trace_idt_enabled())
+ load_trace_idt();
+ else
+ load_idt((const struct desc_ptr *)&idt_descr);
+}
+#endif /* _ASM_X86_DESC_H */