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authorLinus Torvalds <torvalds@linux-foundation.org>2015-02-12 17:51:56 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2015-02-12 17:51:56 +0100
commit42cf0f203e877cc7e502883d43b3f72149033d86 (patch)
tree3658297d62f28d7bfaa148099b08001aa9904229 /arch/arm/probes/uprobes/actions-arm.c
parentMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/egt... (diff)
parentMerge branch 'devel-stable' into for-next (diff)
downloadlinux-42cf0f203e877cc7e502883d43b3f72149033d86.tar.xz
linux-42cf0f203e877cc7e502883d43b3f72149033d86.zip
Merge branch 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm
Pull ARM updates from Russell King: - clang assembly fixes from Ard - optimisations and cleanups for Aurora L2 cache support - efficient L2 cache support for secure monitor API on Exynos SoCs - debug menu cleanup from Daniel Thompson to allow better behaviour for multiplatform kernels - StrongARM SA11x0 conversion to irq domains, and pxa_timer - kprobes updates for older ARM CPUs - move probes support out of arch/arm/kernel to arch/arm/probes - add inline asm support for the rbit (reverse bits) instruction - provide an ARM mode secondary CPU entry point (for Qualcomm CPUs) - remove the unused ARMv3 user access code - add driver_override support to AMBA Primecell bus * 'for-linus' of git://ftp.arm.linux.org.uk/~rmk/linux-arm: (55 commits) ARM: 8256/1: driver coamba: add device binding path 'driver_override' ARM: 8301/1: qcom: Use secondary_startup_arm() ARM: 8302/1: Add a secondary_startup that assumes ARM mode ARM: 8300/1: teach __asmeq that r11 == fp and r12 == ip ARM: kprobes: Fix compilation error caused by superfluous '*' ARM: 8297/1: cache-l2x0: optimize aurora range operations ARM: 8296/1: cache-l2x0: clean up aurora cache handling ARM: 8284/1: sa1100: clear RCSR_SMR on resume ARM: 8283/1: sa1100: collie: clear PWER register on machine init ARM: 8282/1: sa1100: use handle_domain_irq ARM: 8281/1: sa1100: move GPIO-related IRQ code to gpio driver ARM: 8280/1: sa1100: switch to irq_domain_add_simple() ARM: 8279/1: sa1100: merge both GPIO irqdomains ARM: 8278/1: sa1100: split irq handling for low GPIOs ARM: 8291/1: replace magic number with PAGE_SHIFT macro in fixup_pv code ARM: 8290/1: decompressor: fix a wrong comment ARM: 8286/1: mm: Fix dma_contiguous_reserve comment ARM: 8248/1: pm: remove outdated comment ARM: 8274/1: Fix DEBUG_LL for multi-platform kernels (without PL01X) ARM: 8273/1: Seperate DEBUG_UART_PHYS from DEBUG_LL on EP93XX ...
Diffstat (limited to 'arch/arm/probes/uprobes/actions-arm.c')
-rw-r--r--arch/arm/probes/uprobes/actions-arm.c232
1 files changed, 232 insertions, 0 deletions
diff --git a/arch/arm/probes/uprobes/actions-arm.c b/arch/arm/probes/uprobes/actions-arm.c
new file mode 100644
index 000000000000..76eb44972ebe
--- /dev/null
+++ b/arch/arm/probes/uprobes/actions-arm.c
@@ -0,0 +1,232 @@
+/*
+ * Copyright (C) 2012 Rabin Vincent <rabin at rab.in>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/stddef.h>
+#include <linux/wait.h>
+#include <linux/uprobes.h>
+#include <linux/module.h>
+
+#include "../decode.h"
+#include "../decode-arm.h"
+#include "core.h"
+
+static int uprobes_substitute_pc(unsigned long *pinsn, u32 oregs)
+{
+ probes_opcode_t insn = __mem_to_opcode_arm(*pinsn);
+ probes_opcode_t temp;
+ probes_opcode_t mask;
+ int freereg;
+ u32 free = 0xffff;
+ u32 regs;
+
+ for (regs = oregs; regs; regs >>= 4, insn >>= 4) {
+ if ((regs & 0xf) == REG_TYPE_NONE)
+ continue;
+
+ free &= ~(1 << (insn & 0xf));
+ }
+
+ /* No PC, no problem */
+ if (free & (1 << 15))
+ return 15;
+
+ if (!free)
+ return -1;
+
+ /*
+ * fls instead of ffs ensures that for "ldrd r0, r1, [pc]" we would
+ * pick LR instead of R1.
+ */
+ freereg = free = fls(free) - 1;
+
+ temp = __mem_to_opcode_arm(*pinsn);
+ insn = temp;
+ regs = oregs;
+ mask = 0xf;
+
+ for (; regs; regs >>= 4, mask <<= 4, free <<= 4, temp >>= 4) {
+ if ((regs & 0xf) == REG_TYPE_NONE)
+ continue;
+
+ if ((temp & 0xf) != 15)
+ continue;
+
+ insn &= ~mask;
+ insn |= free & mask;
+ }
+
+ *pinsn = __opcode_to_mem_arm(insn);
+ return freereg;
+}
+
+static void uprobe_set_pc(struct arch_uprobe *auprobe,
+ struct arch_uprobe_task *autask,
+ struct pt_regs *regs)
+{
+ u32 pcreg = auprobe->pcreg;
+
+ autask->backup = regs->uregs[pcreg];
+ regs->uregs[pcreg] = regs->ARM_pc + 8;
+}
+
+static void uprobe_unset_pc(struct arch_uprobe *auprobe,
+ struct arch_uprobe_task *autask,
+ struct pt_regs *regs)
+{
+ /* PC will be taken care of by common code */
+ regs->uregs[auprobe->pcreg] = autask->backup;
+}
+
+static void uprobe_aluwrite_pc(struct arch_uprobe *auprobe,
+ struct arch_uprobe_task *autask,
+ struct pt_regs *regs)
+{
+ u32 pcreg = auprobe->pcreg;
+
+ alu_write_pc(regs->uregs[pcreg], regs);
+ regs->uregs[pcreg] = autask->backup;
+}
+
+static void uprobe_write_pc(struct arch_uprobe *auprobe,
+ struct arch_uprobe_task *autask,
+ struct pt_regs *regs)
+{
+ u32 pcreg = auprobe->pcreg;
+
+ load_write_pc(regs->uregs[pcreg], regs);
+ regs->uregs[pcreg] = autask->backup;
+}
+
+enum probes_insn
+decode_pc_ro(probes_opcode_t insn, struct arch_probes_insn *asi,
+ const struct decode_header *d)
+{
+ struct arch_uprobe *auprobe = container_of(asi, struct arch_uprobe,
+ asi);
+ struct decode_emulate *decode = (struct decode_emulate *) d;
+ u32 regs = decode->header.type_regs.bits >> DECODE_TYPE_BITS;
+ int reg;
+
+ reg = uprobes_substitute_pc(&auprobe->ixol[0], regs);
+ if (reg == 15)
+ return INSN_GOOD;
+
+ if (reg == -1)
+ return INSN_REJECTED;
+
+ auprobe->pcreg = reg;
+ auprobe->prehandler = uprobe_set_pc;
+ auprobe->posthandler = uprobe_unset_pc;
+
+ return INSN_GOOD;
+}
+
+enum probes_insn
+decode_wb_pc(probes_opcode_t insn, struct arch_probes_insn *asi,
+ const struct decode_header *d, bool alu)
+{
+ struct arch_uprobe *auprobe = container_of(asi, struct arch_uprobe,
+ asi);
+ enum probes_insn ret = decode_pc_ro(insn, asi, d);
+
+ if (((insn >> 12) & 0xf) == 15)
+ auprobe->posthandler = alu ? uprobe_aluwrite_pc
+ : uprobe_write_pc;
+
+ return ret;
+}
+
+enum probes_insn
+decode_rd12rn16rm0rs8_rwflags(probes_opcode_t insn,
+ struct arch_probes_insn *asi,
+ const struct decode_header *d)
+{
+ return decode_wb_pc(insn, asi, d, true);
+}
+
+enum probes_insn
+decode_ldr(probes_opcode_t insn, struct arch_probes_insn *asi,
+ const struct decode_header *d)
+{
+ return decode_wb_pc(insn, asi, d, false);
+}
+
+enum probes_insn
+uprobe_decode_ldmstm(probes_opcode_t insn,
+ struct arch_probes_insn *asi,
+ const struct decode_header *d)
+{
+ struct arch_uprobe *auprobe = container_of(asi, struct arch_uprobe,
+ asi);
+ unsigned reglist = insn & 0xffff;
+ int rn = (insn >> 16) & 0xf;
+ int lbit = insn & (1 << 20);
+ unsigned used = reglist | (1 << rn);
+
+ if (rn == 15)
+ return INSN_REJECTED;
+
+ if (!(used & (1 << 15)))
+ return INSN_GOOD;
+
+ if (used & (1 << 14))
+ return INSN_REJECTED;
+
+ /* Use LR instead of PC */
+ insn ^= 0xc000;
+
+ auprobe->pcreg = 14;
+ auprobe->ixol[0] = __opcode_to_mem_arm(insn);
+
+ auprobe->prehandler = uprobe_set_pc;
+ if (lbit)
+ auprobe->posthandler = uprobe_write_pc;
+ else
+ auprobe->posthandler = uprobe_unset_pc;
+
+ return INSN_GOOD;
+}
+
+const union decode_action uprobes_probes_actions[] = {
+ [PROBES_PRELOAD_IMM] = {.handler = probes_simulate_nop},
+ [PROBES_PRELOAD_REG] = {.handler = probes_simulate_nop},
+ [PROBES_BRANCH_IMM] = {.handler = simulate_blx1},
+ [PROBES_MRS] = {.handler = simulate_mrs},
+ [PROBES_BRANCH_REG] = {.handler = simulate_blx2bx},
+ [PROBES_CLZ] = {.handler = probes_simulate_nop},
+ [PROBES_SATURATING_ARITHMETIC] = {.handler = probes_simulate_nop},
+ [PROBES_MUL1] = {.handler = probes_simulate_nop},
+ [PROBES_MUL2] = {.handler = probes_simulate_nop},
+ [PROBES_SWP] = {.handler = probes_simulate_nop},
+ [PROBES_LDRSTRD] = {.decoder = decode_pc_ro},
+ [PROBES_LOAD_EXTRA] = {.decoder = decode_pc_ro},
+ [PROBES_LOAD] = {.decoder = decode_ldr},
+ [PROBES_STORE_EXTRA] = {.decoder = decode_pc_ro},
+ [PROBES_STORE] = {.decoder = decode_pc_ro},
+ [PROBES_MOV_IP_SP] = {.handler = simulate_mov_ipsp},
+ [PROBES_DATA_PROCESSING_REG] = {
+ .decoder = decode_rd12rn16rm0rs8_rwflags},
+ [PROBES_DATA_PROCESSING_IMM] = {
+ .decoder = decode_rd12rn16rm0rs8_rwflags},
+ [PROBES_MOV_HALFWORD] = {.handler = probes_simulate_nop},
+ [PROBES_SEV] = {.handler = probes_simulate_nop},
+ [PROBES_WFE] = {.handler = probes_simulate_nop},
+ [PROBES_SATURATE] = {.handler = probes_simulate_nop},
+ [PROBES_REV] = {.handler = probes_simulate_nop},
+ [PROBES_MMI] = {.handler = probes_simulate_nop},
+ [PROBES_PACK] = {.handler = probes_simulate_nop},
+ [PROBES_EXTEND] = {.handler = probes_simulate_nop},
+ [PROBES_EXTEND_ADD] = {.handler = probes_simulate_nop},
+ [PROBES_MUL_ADD_LONG] = {.handler = probes_simulate_nop},
+ [PROBES_MUL_ADD] = {.handler = probes_simulate_nop},
+ [PROBES_BITFIELD] = {.handler = probes_simulate_nop},
+ [PROBES_BRANCH] = {.handler = simulate_bbl},
+ [PROBES_LDMSTM] = {.decoder = uprobe_decode_ldmstm}
+};