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-rw-r--r--arch/arm/include/asm/assembler.h372
1 files changed, 290 insertions, 82 deletions
diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h
index 99929122dad7..90fbe4a3f9c8 100644
--- a/arch/arm/include/asm/assembler.h
+++ b/arch/arm/include/asm/assembler.h
@@ -18,11 +18,11 @@
#endif
#include <asm/ptrace.h>
-#include <asm/domain.h>
#include <asm/opcodes-virt.h>
#include <asm/asm-offsets.h>
#include <asm/page.h>
#include <asm/thread_info.h>
+#include <asm/uaccess-asm.h>
#define IOMEM(x) (x)
@@ -86,6 +86,10 @@
#define IMM12_MASK 0xfff
+/* the frame pointer used for stack unwinding */
+ARM( fpreg .req r11 )
+THUMB( fpreg .req r7 )
+
/*
* Enable and disable interrupts
*/
@@ -107,6 +111,16 @@
.endm
#endif
+#if __LINUX_ARM_ARCH__ < 7
+ .macro dsb, args
+ mcr p15, 0, r0, c7, c10, 4
+ .endm
+
+ .macro isb, args
+ mcr p15, 0, r0, c7, c5, 4
+ .endm
+#endif
+
.macro asm_trace_hardirqs_off, save=1
#if defined(CONFIG_TRACE_IRQFLAGS)
.if \save
@@ -203,10 +217,8 @@
* Get current thread_info.
*/
.macro get_thread_info, rd
- ARM( mov \rd, sp, lsr #THREAD_SIZE_ORDER + PAGE_SHIFT )
- THUMB( mov \rd, sp )
- THUMB( lsr \rd, \rd, #THREAD_SIZE_ORDER + PAGE_SHIFT )
- mov \rd, \rd, lsl #THREAD_SIZE_ORDER + PAGE_SHIFT
+ /* thread_info is the first member of struct task_struct */
+ get_current \rd
.endm
/*
@@ -259,7 +271,8 @@
*/
#define ALT_UP(instr...) \
.pushsection ".alt.smp.init", "a" ;\
- .long 9998b ;\
+ .align 2 ;\
+ .long 9998b - . ;\
9997: instr ;\
.if . - 9997b == 2 ;\
nop ;\
@@ -269,10 +282,10 @@
.endif ;\
.popsection
#define ALT_UP_B(label) \
- .equ up_b_offset, label - 9998b ;\
.pushsection ".alt.smp.init", "a" ;\
- .long 9998b ;\
- W(b) . + up_b_offset ;\
+ .align 2 ;\
+ .long 9998b - . ;\
+ W(b) . + (label - 9998b) ;\
.popsection
#else
#define ALT_SMP(instr...)
@@ -280,6 +293,80 @@
#define ALT_UP_B(label) b label
#endif
+ /*
+ * this_cpu_offset - load the per-CPU offset of this CPU into
+ * register 'rd'
+ */
+ .macro this_cpu_offset, rd:req
+#ifdef CONFIG_SMP
+ALT_SMP(mrc p15, 0, \rd, c13, c0, 4)
+#ifdef CONFIG_CPU_V6
+ALT_UP_B(.L1_\@)
+.L0_\@:
+ .subsection 1
+.L1_\@: ldr_va \rd, __per_cpu_offset
+ b .L0_\@
+ .previous
+#endif
+#else
+ mov \rd, #0
+#endif
+ .endm
+
+ /*
+ * set_current - store the task pointer of this CPU's current task
+ */
+ .macro set_current, rn:req, tmp:req
+#if defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || defined(CONFIG_SMP)
+9998: mcr p15, 0, \rn, c13, c0, 3 @ set TPIDRURO register
+#ifdef CONFIG_CPU_V6
+ALT_UP_B(.L0_\@)
+ .subsection 1
+.L0_\@: str_va \rn, __current, \tmp
+ b .L1_\@
+ .previous
+.L1_\@:
+#endif
+#else
+ str_va \rn, __current, \tmp
+#endif
+ .endm
+
+ /*
+ * get_current - load the task pointer of this CPU's current task
+ */
+ .macro get_current, rd:req
+#if defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || defined(CONFIG_SMP)
+9998: mrc p15, 0, \rd, c13, c0, 3 @ get TPIDRURO register
+#ifdef CONFIG_CPU_V6
+ALT_UP_B(.L0_\@)
+ .subsection 1
+.L0_\@: ldr_va \rd, __current
+ b .L1_\@
+ .previous
+.L1_\@:
+#endif
+#else
+ ldr_va \rd, __current
+#endif
+ .endm
+
+ /*
+ * reload_current - reload the task pointer of this CPU's current task
+ * into the TLS register
+ */
+ .macro reload_current, t1:req, t2:req
+#if defined(CONFIG_CURRENT_POINTER_IN_TPIDRURO) || defined(CONFIG_SMP)
+#ifdef CONFIG_CPU_V6
+ALT_SMP(nop)
+ALT_UP_B(.L0_\@)
+#endif
+ ldr_this_cpu \t1, __entry_task, \t1, \t2
+ mcr p15, 0, \t1, c13, c0, 3 @ store in TPIDRURO
+.L0_\@:
+#endif
+ .endm
+
/*
* Instruction barrier
*/
@@ -446,79 +533,6 @@ THUMB( orr \reg , \reg , #PSR_T_BIT )
.size \name , . - \name
.endm
- .macro csdb
-#ifdef CONFIG_THUMB2_KERNEL
- .inst.w 0xf3af8014
-#else
- .inst 0xe320f014
-#endif
- .endm
-
- .macro check_uaccess, addr:req, size:req, limit:req, tmp:req, bad:req
-#ifndef CONFIG_CPU_USE_DOMAINS
- adds \tmp, \addr, #\size - 1
- sbcscc \tmp, \tmp, \limit
- bcs \bad
-#ifdef CONFIG_CPU_SPECTRE
- movcs \addr, #0
- csdb
-#endif
-#endif
- .endm
-
- .macro uaccess_mask_range_ptr, addr:req, size:req, limit:req, tmp:req
-#ifdef CONFIG_CPU_SPECTRE
- sub \tmp, \limit, #1
- subs \tmp, \tmp, \addr @ tmp = limit - 1 - addr
- addhs \tmp, \tmp, #1 @ if (tmp >= 0) {
- subshs \tmp, \tmp, \size @ tmp = limit - (addr + size) }
- movlo \addr, #0 @ if (tmp < 0) addr = NULL
- csdb
-#endif
- .endm
-
- .macro uaccess_disable, tmp, isb=1
-#ifdef CONFIG_CPU_SW_DOMAIN_PAN
- /*
- * Whenever we re-enter userspace, the domains should always be
- * set appropriately.
- */
- mov \tmp, #DACR_UACCESS_DISABLE
- mcr p15, 0, \tmp, c3, c0, 0 @ Set domain register
- .if \isb
- instr_sync
- .endif
-#endif
- .endm
-
- .macro uaccess_enable, tmp, isb=1
-#ifdef CONFIG_CPU_SW_DOMAIN_PAN
- /*
- * Whenever we re-enter userspace, the domains should always be
- * set appropriately.
- */
- mov \tmp, #DACR_UACCESS_ENABLE
- mcr p15, 0, \tmp, c3, c0, 0
- .if \isb
- instr_sync
- .endif
-#endif
- .endm
-
- .macro uaccess_save, tmp
-#ifdef CONFIG_CPU_SW_DOMAIN_PAN
- mrc p15, 0, \tmp, c3, c0, 0
- str \tmp, [sp, #SVC_DACR]
-#endif
- .endm
-
- .macro uaccess_restore
-#ifdef CONFIG_CPU_SW_DOMAIN_PAN
- ldr r0, [sp, #SVC_DACR]
- mcr p15, 0, r0, c3, c0, 0
-#endif
- .endm
-
.irp c,,eq,ne,cs,cc,mi,pl,vs,vc,hi,ls,ge,lt,gt,le,hs,lo
.macro ret\c, reg
#if __LINUX_ARM_ARCH__ < 6
@@ -568,4 +582,198 @@ THUMB( orr \reg , \reg , #PSR_T_BIT )
#define _ASM_NOKPROBE(entry)
#endif
+ .macro __adldst_l, op, reg, sym, tmp, c
+ .if __LINUX_ARM_ARCH__ < 7
+ ldr\c \tmp, .La\@
+ .subsection 1
+ .align 2
+.La\@: .long \sym - .Lpc\@
+ .previous
+ .else
+ .ifnb \c
+ THUMB( ittt \c )
+ .endif
+ movw\c \tmp, #:lower16:\sym - .Lpc\@
+ movt\c \tmp, #:upper16:\sym - .Lpc\@
+ .endif
+
+#ifndef CONFIG_THUMB2_KERNEL
+ .set .Lpc\@, . + 8 // PC bias
+ .ifc \op, add
+ add\c \reg, \tmp, pc
+ .else
+ \op\c \reg, [pc, \tmp]
+ .endif
+#else
+.Lb\@: add\c \tmp, \tmp, pc
+ /*
+ * In Thumb-2 builds, the PC bias depends on whether we are currently
+ * emitting into a .arm or a .thumb section. The size of the add opcode
+ * above will be 2 bytes when emitting in Thumb mode and 4 bytes when
+ * emitting in ARM mode, so let's use this to account for the bias.
+ */
+ .set .Lpc\@, . + (. - .Lb\@)
+
+ .ifnc \op, add
+ \op\c \reg, [\tmp]
+ .endif
+#endif
+ .endm
+
+ /*
+ * mov_l - move a constant value or [relocated] address into a register
+ */
+ .macro mov_l, dst:req, imm:req, cond
+ .if __LINUX_ARM_ARCH__ < 7
+ ldr\cond \dst, =\imm
+ .else
+ movw\cond \dst, #:lower16:\imm
+ movt\cond \dst, #:upper16:\imm
+ .endif
+ .endm
+
+ /*
+ * adr_l - adr pseudo-op with unlimited range
+ *
+ * @dst: destination register
+ * @sym: name of the symbol
+ * @cond: conditional opcode suffix
+ */
+ .macro adr_l, dst:req, sym:req, cond
+ __adldst_l add, \dst, \sym, \dst, \cond
+ .endm
+
+ /*
+ * ldr_l - ldr <literal> pseudo-op with unlimited range
+ *
+ * @dst: destination register
+ * @sym: name of the symbol
+ * @cond: conditional opcode suffix
+ */
+ .macro ldr_l, dst:req, sym:req, cond
+ __adldst_l ldr, \dst, \sym, \dst, \cond
+ .endm
+
+ /*
+ * str_l - str <literal> pseudo-op with unlimited range
+ *
+ * @src: source register
+ * @sym: name of the symbol
+ * @tmp: mandatory scratch register
+ * @cond: conditional opcode suffix
+ */
+ .macro str_l, src:req, sym:req, tmp:req, cond
+ __adldst_l str, \src, \sym, \tmp, \cond
+ .endm
+
+ .macro __ldst_va, op, reg, tmp, sym, cond, offset
+#if __LINUX_ARM_ARCH__ >= 7 || \
+ !defined(CONFIG_ARM_HAS_GROUP_RELOCS) || \
+ (defined(MODULE) && defined(CONFIG_ARM_MODULE_PLTS))
+ mov_l \tmp, \sym, \cond
+#else
+ /*
+ * Avoid a literal load, by emitting a sequence of ADD/LDR instructions
+ * with the appropriate relocations. The combined sequence has a range
+ * of -/+ 256 MiB, which should be sufficient for the core kernel and
+ * for modules loaded into the module region.
+ */
+ .globl \sym
+ .reloc .L0_\@, R_ARM_ALU_PC_G0_NC, \sym
+ .reloc .L1_\@, R_ARM_ALU_PC_G1_NC, \sym
+ .reloc .L2_\@, R_ARM_LDR_PC_G2, \sym
+.L0_\@: sub\cond \tmp, pc, #8 - \offset
+.L1_\@: sub\cond \tmp, \tmp, #4 - \offset
+.L2_\@:
+#endif
+ \op\cond \reg, [\tmp, #\offset]
+ .endm
+
+ /*
+ * ldr_va - load a 32-bit word from the virtual address of \sym
+ */
+ .macro ldr_va, rd:req, sym:req, cond, tmp, offset=0
+ .ifnb \tmp
+ __ldst_va ldr, \rd, \tmp, \sym, \cond, \offset
+ .else
+ __ldst_va ldr, \rd, \rd, \sym, \cond, \offset
+ .endif
+ .endm
+
+ /*
+ * str_va - store a 32-bit word to the virtual address of \sym
+ */
+ .macro str_va, rn:req, sym:req, tmp:req, cond
+ __ldst_va str, \rn, \tmp, \sym, \cond, 0
+ .endm
+
+ /*
+ * ldr_this_cpu_armv6 - Load a 32-bit word from the per-CPU variable 'sym',
+ * without using a temp register. Supported in ARM mode
+ * only.
+ */
+ .macro ldr_this_cpu_armv6, rd:req, sym:req
+ this_cpu_offset \rd
+ .globl \sym
+ .reloc .L0_\@, R_ARM_ALU_PC_G0_NC, \sym
+ .reloc .L1_\@, R_ARM_ALU_PC_G1_NC, \sym
+ .reloc .L2_\@, R_ARM_LDR_PC_G2, \sym
+ add \rd, \rd, pc
+.L0_\@: sub \rd, \rd, #4
+.L1_\@: sub \rd, \rd, #0
+.L2_\@: ldr \rd, [\rd, #4]
+ .endm
+
+ /*
+ * ldr_this_cpu - Load a 32-bit word from the per-CPU variable 'sym'
+ * into register 'rd', which may be the stack pointer,
+ * using 't1' and 't2' as general temp registers. These
+ * are permitted to overlap with 'rd' if != sp
+ */
+ .macro ldr_this_cpu, rd:req, sym:req, t1:req, t2:req
+#ifndef CONFIG_SMP
+ ldr_va \rd, \sym, tmp=\t1
+#elif __LINUX_ARM_ARCH__ >= 7 || \
+ !defined(CONFIG_ARM_HAS_GROUP_RELOCS) || \
+ (defined(MODULE) && defined(CONFIG_ARM_MODULE_PLTS))
+ this_cpu_offset \t1
+ mov_l \t2, \sym
+ ldr \rd, [\t1, \t2]
+#else
+ ldr_this_cpu_armv6 \rd, \sym
+#endif
+ .endm
+
+ /*
+ * rev_l - byte-swap a 32-bit value
+ *
+ * @val: source/destination register
+ * @tmp: scratch register
+ */
+ .macro rev_l, val:req, tmp:req
+ .if __LINUX_ARM_ARCH__ < 6
+ eor \tmp, \val, \val, ror #16
+ bic \tmp, \tmp, #0x00ff0000
+ mov \val, \val, ror #8
+ eor \val, \val, \tmp, lsr #8
+ .else
+ rev \val, \val
+ .endif
+ .endm
+
+ /*
+ * bl_r - branch and link to register
+ *
+ * @dst: target to branch to
+ * @c: conditional opcode suffix
+ */
+ .macro bl_r, dst:req, c
+ .if __LINUX_ARM_ARCH__ < 6
+ mov\c lr, pc
+ mov\c pc, \dst
+ .else
+ blx\c \dst
+ .endif
+ .endm
+
#endif /* __ASM_ASSEMBLER_H__ */