Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 451 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..ab97b22ac
--- /dev/null
+++ b/arch/x86/include/asm/desc.h
@@ -0,0 +1,451 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_DESC_H
+#define _ASM_X86_DESC_H
+
+#include <asm/desc_defs.h>
+#include <asm/ldt.h>
+#include <asm/mmu.h>
+#include <asm/fixmap.h>
+#include <asm/irq_vectors.h>
+#include <asm/cpu_entry_area.h>
+
+#include <linux/debug_locks.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;
+	/* Set the ACCESS bit so it can be mapped RO */
+	desc->type	       |= 1;
+
+	desc->s			= 1;
+	desc->dpl		= 0x3;
+	desc->p			= info->seg_not_present ^ 1;
+	desc->limit1		= (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;
+}
+
+struct gdt_page {
+	struct desc_struct gdt[GDT_ENTRIES];
+} __attribute__((aligned(PAGE_SIZE)));
+
+DECLARE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page);
+
+/* Provide the original GDT */
+static inline struct desc_struct *get_cpu_gdt_rw(unsigned int cpu)
+{
+	return per_cpu(gdt_page, cpu).gdt;
+}
+
+/* Provide the current original GDT */
+static inline struct desc_struct *get_current_gdt_rw(void)
+{
+	return this_cpu_ptr(&gdt_page)->gdt;
+}
+
+/* Provide the fixmap address of the remapped GDT */
+static inline struct desc_struct *get_cpu_gdt_ro(int cpu)
+{
+	return (struct desc_struct *)&get_cpu_entry_area(cpu)->gdt;
+}
+
+/* Provide the current read-only GDT */
+static inline struct desc_struct *get_current_gdt_ro(void)
+{
+	return get_cpu_gdt_ro(smp_processor_id());
+}
+
+/* Provide the physical address of the GDT page. */
+static inline phys_addr_t get_cpu_gdt_paddr(unsigned int cpu)
+{
+	return per_cpu_ptr_to_phys(get_cpu_gdt_rw(cpu));
+}
+
+static inline void pack_gate(gate_desc *gate, unsigned type, unsigned long func,
+			     unsigned dpl, unsigned ist, unsigned seg)
+{
+	gate->offset_low	= (u16) func;
+	gate->bits.p		= 1;
+	gate->bits.dpl		= dpl;
+	gate->bits.zero		= 0;
+	gate->bits.type		= type;
+	gate->offset_middle	= (u16) (func >> 16);
+#ifdef CONFIG_X86_64
+	gate->segment		= __KERNEL_CS;
+	gate->bits.ist		= ist;
+	gate->reserved		= 0;
+	gate->offset_high	= (u32) (func >> 32);
+#else
+	gate->segment		= seg;
+	gate->bits.ist		= 0;
+#endif
+}
+
+static inline int desc_empty(const void *ptr)
+{
+	const u32 *desc = ptr;
+
+	return !(desc[0] | desc[1]);
+}
+
+#ifdef CONFIG_PARAVIRT_XXL
+#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_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_XXL */
+
+#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 set_tssldt_descriptor(void *d, unsigned long addr,
+					 unsigned type, unsigned size)
+{
+	struct ldttss_desc *desc = d;
+
+	memset(desc, 0, sizeof(*desc));
+
+	desc->limit0		= (u16) size;
+	desc->base0		= (u16) addr;
+	desc->base1		= (addr >> 16) & 0xFF;
+	desc->type		= type;
+	desc->p			= 1;
+	desc->limit1		= (size >> 16) & 0xF;
+	desc->base2		= (addr >> 24) & 0xFF;
+#ifdef CONFIG_X86_64
+	desc->base3		= (u32) (addr >> 32);
+#endif
+}
+
+static inline void __set_tss_desc(unsigned cpu, unsigned int entry, struct x86_hw_tss *addr)
+{
+	struct desc_struct *d = get_cpu_gdt_rw(cpu);
+	tss_desc tss;
+
+	set_tssldt_descriptor(&tss, (unsigned long)addr, DESC_TSS,
+			      __KERNEL_TSS_LIMIT);
+	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_rw(cpu), GDT_ENTRY_LDT,
+				&ldt, DESC_LDT);
+		asm volatile("lldt %w0"::"q" (GDT_ENTRY_LDT*8));
+	}
+}
+
+static inline void native_load_gdt(const struct desc_ptr *dtr)
+{
+	asm volatile("lgdt %0"::"m" (*dtr));
+}
+
+static __always_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 store_idt(struct desc_ptr *dtr)
+{
+	asm volatile("sidt %0":"=m" (*dtr));
+}
+
+static inline void native_gdt_invalidate(void)
+{
+	const struct desc_ptr invalid_gdt = {
+		.address = 0,
+		.size = 0
+	};
+
+	native_load_gdt(&invalid_gdt);
+}
+
+static inline void native_idt_invalidate(void)
+{
+	const struct desc_ptr invalid_idt = {
+		.address = 0,
+		.size = 0
+	};
+
+	native_load_idt(&invalid_idt);
+}
+
+/*
+ * The LTR instruction marks the TSS GDT entry as busy. On 64-bit, the GDT is
+ * a read-only remapping. To prevent a page fault, the GDT is switched to the
+ * original writeable version when needed.
+ */
+#ifdef CONFIG_X86_64
+static inline void native_load_tr_desc(void)
+{
+	struct desc_ptr gdt;
+	int cpu = raw_smp_processor_id();
+	bool restore = 0;
+	struct desc_struct *fixmap_gdt;
+
+	native_store_gdt(&gdt);
+	fixmap_gdt = get_cpu_gdt_ro(cpu);
+
+	/*
+	 * If the current GDT is the read-only fixmap, swap to the original
+	 * writeable version. Swap back at the end.
+	 */
+	if (gdt.address == (unsigned long)fixmap_gdt) {
+		load_direct_gdt(cpu);
+		restore = 1;
+	}
+	asm volatile("ltr %w0"::"q" (GDT_ENTRY_TSS*8));
+	if (restore)
+		load_fixmap_gdt(cpu);
+}
+#else
+static inline void native_load_tr_desc(void)
+{
+	asm volatile("ltr %w0"::"q" (GDT_ENTRY_TSS*8));
+}
+#endif
+
+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_rw(cpu);
+	unsigned int i;
+
+	for (i = 0; i < GDT_ENTRY_TLS_ENTRIES; i++)
+		gdt[GDT_ENTRY_TLS_MIN + i] = t->tls_array[i];
+}
+
+DECLARE_PER_CPU(bool, __tss_limit_invalid);
+
+static inline void force_reload_TR(void)
+{
+	struct desc_struct *d = get_current_gdt_rw();
+	tss_desc tss;
+
+	memcpy(&tss, &d[GDT_ENTRY_TSS], sizeof(tss_desc));
+
+	/*
+	 * LTR requires an available TSS, and the TSS is currently
+	 * busy.  Make it be available so that LTR will work.
+	 */
+	tss.type = DESC_TSS;
+	write_gdt_entry(d, GDT_ENTRY_TSS, &tss, DESC_TSS);
+
+	load_TR_desc();
+	this_cpu_write(__tss_limit_invalid, false);
+}
+
+/*
+ * Call this if you need the TSS limit to be correct, which should be the case
+ * if and only if you have TIF_IO_BITMAP set or you're switching to a task
+ * with TIF_IO_BITMAP set.
+ */
+static inline void refresh_tss_limit(void)
+{
+	DEBUG_LOCKS_WARN_ON(preemptible());
+
+	if (unlikely(this_cpu_read(__tss_limit_invalid)))
+		force_reload_TR();
+}
+
+/*
+ * If you do something evil that corrupts the cached TSS limit (I'm looking
+ * at you, VMX exits), call this function.
+ *
+ * The optimization here is that the TSS limit only matters for Linux if the
+ * IO bitmap is in use.  If the TSS limit gets forced to its minimum value,
+ * everything works except that IO bitmap will be ignored and all CPL 3 IO
+ * instructions will #GP, which is exactly what we want for normal tasks.
+ */
+static inline void invalidate_tss_limit(void)
+{
+	DEBUG_LOCKS_WARN_ON(preemptible());
+
+	if (unlikely(test_thread_flag(TIF_IO_BITMAP)))
+		force_reload_TR();
+	else
+		this_cpu_write(__tss_limit_invalid, true);
+}
+
+/* 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);
+}
+
+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->limit1 << 16);
+}
+
+static inline void set_desc_limit(struct desc_struct *desc, unsigned long limit)
+{
+	desc->limit0 = limit & 0xffff;
+	desc->limit1 = (limit >> 16) & 0xf;
+}
+
+void alloc_intr_gate(unsigned int n, const void *addr);
+
+static inline void init_idt_data(struct idt_data *data, unsigned int n,
+				 const void *addr)
+{
+	BUG_ON(n > 0xFF);
+
+	memset(data, 0, sizeof(*data));
+	data->vector	= n;
+	data->addr	= addr;
+	data->segment	= __KERNEL_CS;
+	data->bits.type	= GATE_INTERRUPT;
+	data->bits.p	= 1;
+}
+
+static inline void idt_init_desc(gate_desc *gate, const struct idt_data *d)
+{
+	unsigned long addr = (unsigned long) d->addr;
+
+	gate->offset_low	= (u16) addr;
+	gate->segment		= (u16) d->segment;
+	gate->bits		= d->bits;
+	gate->offset_middle	= (u16) (addr >> 16);
+#ifdef CONFIG_X86_64
+	gate->offset_high	= (u32) (addr >> 32);
+	gate->reserved		= 0;
+#endif
+}
+
+extern unsigned long system_vectors[];
+
+extern void load_current_idt(void);
+extern void idt_setup_early_handler(void);
+extern void idt_setup_early_traps(void);
+extern void idt_setup_traps(void);
+extern void idt_setup_apic_and_irq_gates(void);
+extern bool idt_is_f00f_address(unsigned long address);
+
+#ifdef CONFIG_X86_64
+extern void idt_setup_early_pf(void);
+#else
+static inline void idt_setup_early_pf(void) { }
+#endif
+
+extern void idt_invalidate(void);
+
+#endif /* _ASM_X86_DESC_H */