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-rw-r--r--arch/loongarch/kernel/ptrace.c1080
1 files changed, 1080 insertions, 0 deletions
diff --git a/arch/loongarch/kernel/ptrace.c b/arch/loongarch/kernel/ptrace.c
new file mode 100644
index 0000000000..c114c5ef13
--- /dev/null
+++ b/arch/loongarch/kernel/ptrace.c
@@ -0,0 +1,1080 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Author: Hanlu Li <lihanlu@loongson.cn>
+ * Huacai Chen <chenhuacai@loongson.cn>
+ *
+ * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
+ *
+ * Derived from MIPS:
+ * Copyright (C) 1992 Ross Biro
+ * Copyright (C) Linus Torvalds
+ * Copyright (C) 1994, 95, 96, 97, 98, 2000 Ralf Baechle
+ * Copyright (C) 1996 David S. Miller
+ * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
+ * Copyright (C) 1999 MIPS Technologies, Inc.
+ * Copyright (C) 2000 Ulf Carlsson
+ */
+#include <linux/kernel.h>
+#include <linux/audit.h>
+#include <linux/compiler.h>
+#include <linux/context_tracking.h>
+#include <linux/elf.h>
+#include <linux/errno.h>
+#include <linux/hw_breakpoint.h>
+#include <linux/mm.h>
+#include <linux/nospec.h>
+#include <linux/ptrace.h>
+#include <linux/regset.h>
+#include <linux/sched.h>
+#include <linux/sched/task_stack.h>
+#include <linux/security.h>
+#include <linux/smp.h>
+#include <linux/stddef.h>
+#include <linux/seccomp.h>
+#include <linux/thread_info.h>
+#include <linux/uaccess.h>
+
+#include <asm/byteorder.h>
+#include <asm/cpu.h>
+#include <asm/cpu-info.h>
+#include <asm/fpu.h>
+#include <asm/lbt.h>
+#include <asm/loongarch.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/processor.h>
+#include <asm/ptrace.h>
+#include <asm/reg.h>
+#include <asm/syscall.h>
+
+static void init_fp_ctx(struct task_struct *target)
+{
+ /* The target already has context */
+ if (tsk_used_math(target))
+ return;
+
+ /* Begin with data registers set to all 1s... */
+ memset(&target->thread.fpu.fpr, ~0, sizeof(target->thread.fpu.fpr));
+ set_stopped_child_used_math(target);
+}
+
+/*
+ * Called by kernel/ptrace.c when detaching..
+ *
+ * Make sure single step bits etc are not set.
+ */
+void ptrace_disable(struct task_struct *child)
+{
+ /* Don't load the watchpoint registers for the ex-child. */
+ clear_tsk_thread_flag(child, TIF_LOAD_WATCH);
+ clear_tsk_thread_flag(child, TIF_SINGLESTEP);
+}
+
+/* regset get/set implementations */
+
+static int gpr_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ int r;
+ struct pt_regs *regs = task_pt_regs(target);
+
+ r = membuf_write(&to, &regs->regs, sizeof(u64) * GPR_NUM);
+ r = membuf_write(&to, &regs->orig_a0, sizeof(u64));
+ r = membuf_write(&to, &regs->csr_era, sizeof(u64));
+ r = membuf_write(&to, &regs->csr_badvaddr, sizeof(u64));
+
+ return r;
+}
+
+static int gpr_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ int err;
+ int a0_start = sizeof(u64) * GPR_NUM;
+ int era_start = a0_start + sizeof(u64);
+ int badvaddr_start = era_start + sizeof(u64);
+ struct pt_regs *regs = task_pt_regs(target);
+
+ err = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &regs->regs,
+ 0, a0_start);
+ err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &regs->orig_a0,
+ a0_start, a0_start + sizeof(u64));
+ err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &regs->csr_era,
+ era_start, era_start + sizeof(u64));
+ err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &regs->csr_badvaddr,
+ badvaddr_start, badvaddr_start + sizeof(u64));
+
+ return err;
+}
+
+
+/*
+ * Get the general floating-point registers.
+ */
+static int gfpr_get(struct task_struct *target, struct membuf *to)
+{
+ return membuf_write(to, &target->thread.fpu.fpr,
+ sizeof(elf_fpreg_t) * NUM_FPU_REGS);
+}
+
+static int gfpr_get_simd(struct task_struct *target, struct membuf *to)
+{
+ int i, r;
+ u64 fpr_val;
+
+ BUILD_BUG_ON(sizeof(fpr_val) != sizeof(elf_fpreg_t));
+ for (i = 0; i < NUM_FPU_REGS; i++) {
+ fpr_val = get_fpr64(&target->thread.fpu.fpr[i], 0);
+ r = membuf_write(to, &fpr_val, sizeof(elf_fpreg_t));
+ }
+
+ return r;
+}
+
+/*
+ * Choose the appropriate helper for general registers, and then copy
+ * the FCC and FCSR registers separately.
+ */
+static int fpr_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ int r;
+
+ save_fpu_regs(target);
+
+ if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t))
+ r = gfpr_get(target, &to);
+ else
+ r = gfpr_get_simd(target, &to);
+
+ r = membuf_write(&to, &target->thread.fpu.fcc, sizeof(target->thread.fpu.fcc));
+ r = membuf_write(&to, &target->thread.fpu.fcsr, sizeof(target->thread.fpu.fcsr));
+
+ return r;
+}
+
+static int gfpr_set(struct task_struct *target,
+ unsigned int *pos, unsigned int *count,
+ const void **kbuf, const void __user **ubuf)
+{
+ return user_regset_copyin(pos, count, kbuf, ubuf,
+ &target->thread.fpu.fpr,
+ 0, NUM_FPU_REGS * sizeof(elf_fpreg_t));
+}
+
+static int gfpr_set_simd(struct task_struct *target,
+ unsigned int *pos, unsigned int *count,
+ const void **kbuf, const void __user **ubuf)
+{
+ int i, err;
+ u64 fpr_val;
+
+ BUILD_BUG_ON(sizeof(fpr_val) != sizeof(elf_fpreg_t));
+ for (i = 0; i < NUM_FPU_REGS && *count > 0; i++) {
+ err = user_regset_copyin(pos, count, kbuf, ubuf,
+ &fpr_val, i * sizeof(elf_fpreg_t),
+ (i + 1) * sizeof(elf_fpreg_t));
+ if (err)
+ return err;
+ set_fpr64(&target->thread.fpu.fpr[i], 0, fpr_val);
+ }
+
+ return 0;
+}
+
+/*
+ * Choose the appropriate helper for general registers, and then copy
+ * the FCC register separately.
+ */
+static int fpr_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ const int fcc_start = NUM_FPU_REGS * sizeof(elf_fpreg_t);
+ const int fcsr_start = fcc_start + sizeof(u64);
+ int err;
+
+ BUG_ON(count % sizeof(elf_fpreg_t));
+ if (pos + count > sizeof(elf_fpregset_t))
+ return -EIO;
+
+ init_fp_ctx(target);
+
+ if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t))
+ err = gfpr_set(target, &pos, &count, &kbuf, &ubuf);
+ else
+ err = gfpr_set_simd(target, &pos, &count, &kbuf, &ubuf);
+ if (err)
+ return err;
+
+ err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &target->thread.fpu.fcc, fcc_start,
+ fcc_start + sizeof(u64));
+ err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &target->thread.fpu.fcsr, fcsr_start,
+ fcsr_start + sizeof(u32));
+
+ return err;
+}
+
+static int cfg_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ int i, r;
+ u32 cfg_val;
+
+ i = 0;
+ while (to.left > 0) {
+ cfg_val = read_cpucfg(i++);
+ r = membuf_write(&to, &cfg_val, sizeof(u32));
+ }
+
+ return r;
+}
+
+/*
+ * CFG registers are read-only.
+ */
+static int cfg_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ return 0;
+}
+
+#ifdef CONFIG_CPU_HAS_LSX
+
+static void copy_pad_fprs(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf *to, unsigned int live_sz)
+{
+ int i, j;
+ unsigned long long fill = ~0ull;
+ unsigned int cp_sz, pad_sz;
+
+ cp_sz = min(regset->size, live_sz);
+ pad_sz = regset->size - cp_sz;
+ WARN_ON(pad_sz % sizeof(fill));
+
+ for (i = 0; i < NUM_FPU_REGS; i++) {
+ membuf_write(to, &target->thread.fpu.fpr[i], cp_sz);
+ for (j = 0; j < (pad_sz / sizeof(fill)); j++) {
+ membuf_store(to, fill);
+ }
+ }
+}
+
+static int simd_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ const unsigned int wr_size = NUM_FPU_REGS * regset->size;
+
+ save_fpu_regs(target);
+
+ if (!tsk_used_math(target)) {
+ /* The task hasn't used FP or LSX, fill with 0xff */
+ copy_pad_fprs(target, regset, &to, 0);
+ } else if (!test_tsk_thread_flag(target, TIF_LSX_CTX_LIVE)) {
+ /* Copy scalar FP context, fill the rest with 0xff */
+ copy_pad_fprs(target, regset, &to, 8);
+#ifdef CONFIG_CPU_HAS_LASX
+ } else if (!test_tsk_thread_flag(target, TIF_LASX_CTX_LIVE)) {
+ /* Copy LSX 128 Bit context, fill the rest with 0xff */
+ copy_pad_fprs(target, regset, &to, 16);
+#endif
+ } else if (sizeof(target->thread.fpu.fpr[0]) == regset->size) {
+ /* Trivially copy the vector registers */
+ membuf_write(&to, &target->thread.fpu.fpr, wr_size);
+ } else {
+ /* Copy as much context as possible, fill the rest with 0xff */
+ copy_pad_fprs(target, regset, &to, sizeof(target->thread.fpu.fpr[0]));
+ }
+
+ return 0;
+}
+
+static int simd_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ const unsigned int wr_size = NUM_FPU_REGS * regset->size;
+ unsigned int cp_sz;
+ int i, err, start;
+
+ init_fp_ctx(target);
+
+ if (sizeof(target->thread.fpu.fpr[0]) == regset->size) {
+ /* Trivially copy the vector registers */
+ err = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &target->thread.fpu.fpr,
+ 0, wr_size);
+ } else {
+ /* Copy as much context as possible */
+ cp_sz = min_t(unsigned int, regset->size,
+ sizeof(target->thread.fpu.fpr[0]));
+
+ i = start = err = 0;
+ for (; i < NUM_FPU_REGS; i++, start += regset->size) {
+ err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &target->thread.fpu.fpr[i],
+ start, start + cp_sz);
+ }
+ }
+
+ return err;
+}
+
+#endif /* CONFIG_CPU_HAS_LSX */
+
+#ifdef CONFIG_CPU_HAS_LBT
+static int lbt_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ int r;
+
+ r = membuf_write(&to, &target->thread.lbt.scr0, sizeof(target->thread.lbt.scr0));
+ r = membuf_write(&to, &target->thread.lbt.scr1, sizeof(target->thread.lbt.scr1));
+ r = membuf_write(&to, &target->thread.lbt.scr2, sizeof(target->thread.lbt.scr2));
+ r = membuf_write(&to, &target->thread.lbt.scr3, sizeof(target->thread.lbt.scr3));
+ r = membuf_write(&to, &target->thread.lbt.eflags, sizeof(u32));
+ r = membuf_write(&to, &target->thread.fpu.ftop, sizeof(u32));
+
+ return r;
+}
+
+static int lbt_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ int err = 0;
+ const int eflags_start = 4 * sizeof(target->thread.lbt.scr0);
+ const int ftop_start = eflags_start + sizeof(u32);
+
+ err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &target->thread.lbt.scr0,
+ 0, 4 * sizeof(target->thread.lbt.scr0));
+ err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &target->thread.lbt.eflags,
+ eflags_start, ftop_start);
+ err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf,
+ &target->thread.fpu.ftop,
+ ftop_start, ftop_start + sizeof(u32));
+
+ return err;
+}
+#endif /* CONFIG_CPU_HAS_LBT */
+
+#ifdef CONFIG_HAVE_HW_BREAKPOINT
+
+/*
+ * Handle hitting a HW-breakpoint.
+ */
+static void ptrace_hbptriggered(struct perf_event *bp,
+ struct perf_sample_data *data,
+ struct pt_regs *regs)
+{
+ int i;
+ struct arch_hw_breakpoint *bkpt = counter_arch_bp(bp);
+
+ for (i = 0; i < LOONGARCH_MAX_BRP; ++i)
+ if (current->thread.hbp_break[i] == bp)
+ break;
+
+ for (i = 0; i < LOONGARCH_MAX_WRP; ++i)
+ if (current->thread.hbp_watch[i] == bp)
+ break;
+
+ force_sig_ptrace_errno_trap(i, (void __user *)bkpt->address);
+}
+
+static struct perf_event *ptrace_hbp_get_event(unsigned int note_type,
+ struct task_struct *tsk,
+ unsigned long idx)
+{
+ struct perf_event *bp;
+
+ switch (note_type) {
+ case NT_LOONGARCH_HW_BREAK:
+ if (idx >= LOONGARCH_MAX_BRP)
+ return ERR_PTR(-EINVAL);
+ idx = array_index_nospec(idx, LOONGARCH_MAX_BRP);
+ bp = tsk->thread.hbp_break[idx];
+ break;
+ case NT_LOONGARCH_HW_WATCH:
+ if (idx >= LOONGARCH_MAX_WRP)
+ return ERR_PTR(-EINVAL);
+ idx = array_index_nospec(idx, LOONGARCH_MAX_WRP);
+ bp = tsk->thread.hbp_watch[idx];
+ break;
+ }
+
+ return bp;
+}
+
+static int ptrace_hbp_set_event(unsigned int note_type,
+ struct task_struct *tsk,
+ unsigned long idx,
+ struct perf_event *bp)
+{
+ switch (note_type) {
+ case NT_LOONGARCH_HW_BREAK:
+ if (idx >= LOONGARCH_MAX_BRP)
+ return -EINVAL;
+ idx = array_index_nospec(idx, LOONGARCH_MAX_BRP);
+ tsk->thread.hbp_break[idx] = bp;
+ break;
+ case NT_LOONGARCH_HW_WATCH:
+ if (idx >= LOONGARCH_MAX_WRP)
+ return -EINVAL;
+ idx = array_index_nospec(idx, LOONGARCH_MAX_WRP);
+ tsk->thread.hbp_watch[idx] = bp;
+ break;
+ }
+
+ return 0;
+}
+
+static struct perf_event *ptrace_hbp_create(unsigned int note_type,
+ struct task_struct *tsk,
+ unsigned long idx)
+{
+ int err, type;
+ struct perf_event *bp;
+ struct perf_event_attr attr;
+
+ switch (note_type) {
+ case NT_LOONGARCH_HW_BREAK:
+ type = HW_BREAKPOINT_X;
+ break;
+ case NT_LOONGARCH_HW_WATCH:
+ type = HW_BREAKPOINT_RW;
+ break;
+ default:
+ return ERR_PTR(-EINVAL);
+ }
+
+ ptrace_breakpoint_init(&attr);
+
+ /*
+ * Initialise fields to sane defaults
+ * (i.e. values that will pass validation).
+ */
+ attr.bp_addr = 0;
+ attr.bp_len = HW_BREAKPOINT_LEN_4;
+ attr.bp_type = type;
+ attr.disabled = 1;
+
+ bp = register_user_hw_breakpoint(&attr, ptrace_hbptriggered, NULL, tsk);
+ if (IS_ERR(bp))
+ return bp;
+
+ err = ptrace_hbp_set_event(note_type, tsk, idx, bp);
+ if (err)
+ return ERR_PTR(err);
+
+ return bp;
+}
+
+static int ptrace_hbp_fill_attr_ctrl(unsigned int note_type,
+ struct arch_hw_breakpoint_ctrl ctrl,
+ struct perf_event_attr *attr)
+{
+ int err, len, type, offset;
+
+ err = arch_bp_generic_fields(ctrl, &len, &type, &offset);
+ if (err)
+ return err;
+
+ switch (note_type) {
+ case NT_LOONGARCH_HW_BREAK:
+ if ((type & HW_BREAKPOINT_X) != type)
+ return -EINVAL;
+ break;
+ case NT_LOONGARCH_HW_WATCH:
+ if ((type & HW_BREAKPOINT_RW) != type)
+ return -EINVAL;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ attr->bp_len = len;
+ attr->bp_type = type;
+ attr->bp_addr += offset;
+
+ return 0;
+}
+
+static int ptrace_hbp_get_resource_info(unsigned int note_type, u64 *info)
+{
+ u8 num;
+ u64 reg = 0;
+
+ switch (note_type) {
+ case NT_LOONGARCH_HW_BREAK:
+ num = hw_breakpoint_slots(TYPE_INST);
+ break;
+ case NT_LOONGARCH_HW_WATCH:
+ num = hw_breakpoint_slots(TYPE_DATA);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ *info = reg | num;
+
+ return 0;
+}
+
+static struct perf_event *ptrace_hbp_get_initialised_bp(unsigned int note_type,
+ struct task_struct *tsk,
+ unsigned long idx)
+{
+ struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
+
+ if (!bp)
+ bp = ptrace_hbp_create(note_type, tsk, idx);
+
+ return bp;
+}
+
+static int ptrace_hbp_get_ctrl(unsigned int note_type,
+ struct task_struct *tsk,
+ unsigned long idx, u32 *ctrl)
+{
+ struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
+
+ if (IS_ERR(bp))
+ return PTR_ERR(bp);
+
+ *ctrl = bp ? encode_ctrl_reg(counter_arch_bp(bp)->ctrl) : 0;
+
+ return 0;
+}
+
+static int ptrace_hbp_get_mask(unsigned int note_type,
+ struct task_struct *tsk,
+ unsigned long idx, u64 *mask)
+{
+ struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
+
+ if (IS_ERR(bp))
+ return PTR_ERR(bp);
+
+ *mask = bp ? counter_arch_bp(bp)->mask : 0;
+
+ return 0;
+}
+
+static int ptrace_hbp_get_addr(unsigned int note_type,
+ struct task_struct *tsk,
+ unsigned long idx, u64 *addr)
+{
+ struct perf_event *bp = ptrace_hbp_get_event(note_type, tsk, idx);
+
+ if (IS_ERR(bp))
+ return PTR_ERR(bp);
+
+ *addr = bp ? counter_arch_bp(bp)->address : 0;
+
+ return 0;
+}
+
+static int ptrace_hbp_set_ctrl(unsigned int note_type,
+ struct task_struct *tsk,
+ unsigned long idx, u32 uctrl)
+{
+ int err;
+ struct perf_event *bp;
+ struct perf_event_attr attr;
+ struct arch_hw_breakpoint_ctrl ctrl;
+
+ bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx);
+ if (IS_ERR(bp))
+ return PTR_ERR(bp);
+
+ attr = bp->attr;
+ decode_ctrl_reg(uctrl, &ctrl);
+ err = ptrace_hbp_fill_attr_ctrl(note_type, ctrl, &attr);
+ if (err)
+ return err;
+
+ return modify_user_hw_breakpoint(bp, &attr);
+}
+
+static int ptrace_hbp_set_mask(unsigned int note_type,
+ struct task_struct *tsk,
+ unsigned long idx, u64 mask)
+{
+ struct perf_event *bp;
+ struct perf_event_attr attr;
+ struct arch_hw_breakpoint *info;
+
+ bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx);
+ if (IS_ERR(bp))
+ return PTR_ERR(bp);
+
+ attr = bp->attr;
+ info = counter_arch_bp(bp);
+ info->mask = mask;
+
+ return modify_user_hw_breakpoint(bp, &attr);
+}
+
+static int ptrace_hbp_set_addr(unsigned int note_type,
+ struct task_struct *tsk,
+ unsigned long idx, u64 addr)
+{
+ struct perf_event *bp;
+ struct perf_event_attr attr;
+
+ bp = ptrace_hbp_get_initialised_bp(note_type, tsk, idx);
+ if (IS_ERR(bp))
+ return PTR_ERR(bp);
+
+ attr = bp->attr;
+ attr.bp_addr = addr;
+
+ return modify_user_hw_breakpoint(bp, &attr);
+}
+
+#define PTRACE_HBP_ADDR_SZ sizeof(u64)
+#define PTRACE_HBP_MASK_SZ sizeof(u64)
+#define PTRACE_HBP_CTRL_SZ sizeof(u32)
+#define PTRACE_HBP_PAD_SZ sizeof(u32)
+
+static int hw_break_get(struct task_struct *target,
+ const struct user_regset *regset,
+ struct membuf to)
+{
+ u64 info;
+ u32 ctrl;
+ u64 addr, mask;
+ int ret, idx = 0;
+ unsigned int note_type = regset->core_note_type;
+
+ /* Resource info */
+ ret = ptrace_hbp_get_resource_info(note_type, &info);
+ if (ret)
+ return ret;
+
+ membuf_write(&to, &info, sizeof(info));
+
+ /* (address, mask, ctrl) registers */
+ while (to.left) {
+ ret = ptrace_hbp_get_addr(note_type, target, idx, &addr);
+ if (ret)
+ return ret;
+
+ ret = ptrace_hbp_get_mask(note_type, target, idx, &mask);
+ if (ret)
+ return ret;
+
+ ret = ptrace_hbp_get_ctrl(note_type, target, idx, &ctrl);
+ if (ret)
+ return ret;
+
+ membuf_store(&to, addr);
+ membuf_store(&to, mask);
+ membuf_store(&to, ctrl);
+ membuf_zero(&to, sizeof(u32));
+ idx++;
+ }
+
+ return 0;
+}
+
+static int hw_break_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ u32 ctrl;
+ u64 addr, mask;
+ int ret, idx = 0, offset, limit;
+ unsigned int note_type = regset->core_note_type;
+
+ /* Resource info */
+ offset = offsetof(struct user_watch_state, dbg_regs);
+ user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 0, offset);
+
+ /* (address, mask, ctrl) registers */
+ limit = regset->n * regset->size;
+ while (count && offset < limit) {
+ if (count < PTRACE_HBP_ADDR_SZ)
+ return -EINVAL;
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &addr,
+ offset, offset + PTRACE_HBP_ADDR_SZ);
+ if (ret)
+ return ret;
+
+ ret = ptrace_hbp_set_addr(note_type, target, idx, addr);
+ if (ret)
+ return ret;
+ offset += PTRACE_HBP_ADDR_SZ;
+
+ if (!count)
+ break;
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &mask,
+ offset, offset + PTRACE_HBP_MASK_SZ);
+ if (ret)
+ return ret;
+
+ ret = ptrace_hbp_set_mask(note_type, target, idx, mask);
+ if (ret)
+ return ret;
+ offset += PTRACE_HBP_MASK_SZ;
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ctrl,
+ offset, offset + PTRACE_HBP_CTRL_SZ);
+ if (ret)
+ return ret;
+
+ ret = ptrace_hbp_set_ctrl(note_type, target, idx, ctrl);
+ if (ret)
+ return ret;
+ offset += PTRACE_HBP_CTRL_SZ;
+
+ user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
+ offset, offset + PTRACE_HBP_PAD_SZ);
+ offset += PTRACE_HBP_PAD_SZ;
+
+ idx++;
+ }
+
+ return 0;
+}
+
+#endif
+
+struct pt_regs_offset {
+ const char *name;
+ int offset;
+};
+
+#define REG_OFFSET_NAME(n, r) {.name = #n, .offset = offsetof(struct pt_regs, r)}
+#define REG_OFFSET_END {.name = NULL, .offset = 0}
+
+static const struct pt_regs_offset regoffset_table[] = {
+ REG_OFFSET_NAME(r0, regs[0]),
+ REG_OFFSET_NAME(r1, regs[1]),
+ REG_OFFSET_NAME(r2, regs[2]),
+ REG_OFFSET_NAME(r3, regs[3]),
+ REG_OFFSET_NAME(r4, regs[4]),
+ REG_OFFSET_NAME(r5, regs[5]),
+ REG_OFFSET_NAME(r6, regs[6]),
+ REG_OFFSET_NAME(r7, regs[7]),
+ REG_OFFSET_NAME(r8, regs[8]),
+ REG_OFFSET_NAME(r9, regs[9]),
+ REG_OFFSET_NAME(r10, regs[10]),
+ REG_OFFSET_NAME(r11, regs[11]),
+ REG_OFFSET_NAME(r12, regs[12]),
+ REG_OFFSET_NAME(r13, regs[13]),
+ REG_OFFSET_NAME(r14, regs[14]),
+ REG_OFFSET_NAME(r15, regs[15]),
+ REG_OFFSET_NAME(r16, regs[16]),
+ REG_OFFSET_NAME(r17, regs[17]),
+ REG_OFFSET_NAME(r18, regs[18]),
+ REG_OFFSET_NAME(r19, regs[19]),
+ REG_OFFSET_NAME(r20, regs[20]),
+ REG_OFFSET_NAME(r21, regs[21]),
+ REG_OFFSET_NAME(r22, regs[22]),
+ REG_OFFSET_NAME(r23, regs[23]),
+ REG_OFFSET_NAME(r24, regs[24]),
+ REG_OFFSET_NAME(r25, regs[25]),
+ REG_OFFSET_NAME(r26, regs[26]),
+ REG_OFFSET_NAME(r27, regs[27]),
+ REG_OFFSET_NAME(r28, regs[28]),
+ REG_OFFSET_NAME(r29, regs[29]),
+ REG_OFFSET_NAME(r30, regs[30]),
+ REG_OFFSET_NAME(r31, regs[31]),
+ REG_OFFSET_NAME(orig_a0, orig_a0),
+ REG_OFFSET_NAME(csr_era, csr_era),
+ REG_OFFSET_NAME(csr_badvaddr, csr_badvaddr),
+ REG_OFFSET_NAME(csr_crmd, csr_crmd),
+ REG_OFFSET_NAME(csr_prmd, csr_prmd),
+ REG_OFFSET_NAME(csr_euen, csr_euen),
+ REG_OFFSET_NAME(csr_ecfg, csr_ecfg),
+ REG_OFFSET_NAME(csr_estat, csr_estat),
+ REG_OFFSET_END,
+};
+
+/**
+ * regs_query_register_offset() - query register offset from its name
+ * @name: the name of a register
+ *
+ * regs_query_register_offset() returns the offset of a register in struct
+ * pt_regs from its name. If the name is invalid, this returns -EINVAL;
+ */
+int regs_query_register_offset(const char *name)
+{
+ const struct pt_regs_offset *roff;
+
+ for (roff = regoffset_table; roff->name != NULL; roff++)
+ if (!strcmp(roff->name, name))
+ return roff->offset;
+ return -EINVAL;
+}
+
+enum loongarch_regset {
+ REGSET_GPR,
+ REGSET_FPR,
+ REGSET_CPUCFG,
+#ifdef CONFIG_CPU_HAS_LSX
+ REGSET_LSX,
+#endif
+#ifdef CONFIG_CPU_HAS_LASX
+ REGSET_LASX,
+#endif
+#ifdef CONFIG_CPU_HAS_LBT
+ REGSET_LBT,
+#endif
+#ifdef CONFIG_HAVE_HW_BREAKPOINT
+ REGSET_HW_BREAK,
+ REGSET_HW_WATCH,
+#endif
+};
+
+static const struct user_regset loongarch64_regsets[] = {
+ [REGSET_GPR] = {
+ .core_note_type = NT_PRSTATUS,
+ .n = ELF_NGREG,
+ .size = sizeof(elf_greg_t),
+ .align = sizeof(elf_greg_t),
+ .regset_get = gpr_get,
+ .set = gpr_set,
+ },
+ [REGSET_FPR] = {
+ .core_note_type = NT_PRFPREG,
+ .n = ELF_NFPREG,
+ .size = sizeof(elf_fpreg_t),
+ .align = sizeof(elf_fpreg_t),
+ .regset_get = fpr_get,
+ .set = fpr_set,
+ },
+ [REGSET_CPUCFG] = {
+ .core_note_type = NT_LOONGARCH_CPUCFG,
+ .n = 64,
+ .size = sizeof(u32),
+ .align = sizeof(u32),
+ .regset_get = cfg_get,
+ .set = cfg_set,
+ },
+#ifdef CONFIG_CPU_HAS_LSX
+ [REGSET_LSX] = {
+ .core_note_type = NT_LOONGARCH_LSX,
+ .n = NUM_FPU_REGS,
+ .size = 16,
+ .align = 16,
+ .regset_get = simd_get,
+ .set = simd_set,
+ },
+#endif
+#ifdef CONFIG_CPU_HAS_LASX
+ [REGSET_LASX] = {
+ .core_note_type = NT_LOONGARCH_LASX,
+ .n = NUM_FPU_REGS,
+ .size = 32,
+ .align = 32,
+ .regset_get = simd_get,
+ .set = simd_set,
+ },
+#endif
+#ifdef CONFIG_CPU_HAS_LBT
+ [REGSET_LBT] = {
+ .core_note_type = NT_LOONGARCH_LBT,
+ .n = 5,
+ .size = sizeof(u64),
+ .align = sizeof(u64),
+ .regset_get = lbt_get,
+ .set = lbt_set,
+ },
+#endif
+#ifdef CONFIG_HAVE_HW_BREAKPOINT
+ [REGSET_HW_BREAK] = {
+ .core_note_type = NT_LOONGARCH_HW_BREAK,
+ .n = sizeof(struct user_watch_state) / sizeof(u32),
+ .size = sizeof(u32),
+ .align = sizeof(u32),
+ .regset_get = hw_break_get,
+ .set = hw_break_set,
+ },
+ [REGSET_HW_WATCH] = {
+ .core_note_type = NT_LOONGARCH_HW_WATCH,
+ .n = sizeof(struct user_watch_state) / sizeof(u32),
+ .size = sizeof(u32),
+ .align = sizeof(u32),
+ .regset_get = hw_break_get,
+ .set = hw_break_set,
+ },
+#endif
+};
+
+static const struct user_regset_view user_loongarch64_view = {
+ .name = "loongarch64",
+ .e_machine = ELF_ARCH,
+ .regsets = loongarch64_regsets,
+ .n = ARRAY_SIZE(loongarch64_regsets),
+};
+
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+ return &user_loongarch64_view;
+}
+
+static inline int read_user(struct task_struct *target, unsigned long addr,
+ unsigned long __user *data)
+{
+ unsigned long tmp = 0;
+
+ switch (addr) {
+ case 0 ... 31:
+ tmp = task_pt_regs(target)->regs[addr];
+ break;
+ case ARG0:
+ tmp = task_pt_regs(target)->orig_a0;
+ break;
+ case PC:
+ tmp = task_pt_regs(target)->csr_era;
+ break;
+ case BADVADDR:
+ tmp = task_pt_regs(target)->csr_badvaddr;
+ break;
+ default:
+ return -EIO;
+ }
+
+ return put_user(tmp, data);
+}
+
+static inline int write_user(struct task_struct *target, unsigned long addr,
+ unsigned long data)
+{
+ switch (addr) {
+ case 0 ... 31:
+ task_pt_regs(target)->regs[addr] = data;
+ break;
+ case ARG0:
+ task_pt_regs(target)->orig_a0 = data;
+ break;
+ case PC:
+ task_pt_regs(target)->csr_era = data;
+ break;
+ case BADVADDR:
+ task_pt_regs(target)->csr_badvaddr = data;
+ break;
+ default:
+ return -EIO;
+ }
+
+ return 0;
+}
+
+long arch_ptrace(struct task_struct *child, long request,
+ unsigned long addr, unsigned long data)
+{
+ int ret;
+ unsigned long __user *datap = (void __user *) data;
+
+ switch (request) {
+ case PTRACE_PEEKUSR:
+ ret = read_user(child, addr, datap);
+ break;
+
+ case PTRACE_POKEUSR:
+ ret = write_user(child, addr, data);
+ break;
+
+ default:
+ ret = ptrace_request(child, request, addr, data);
+ break;
+ }
+
+ return ret;
+}
+
+#ifdef CONFIG_HAVE_HW_BREAKPOINT
+static void ptrace_triggered(struct perf_event *bp,
+ struct perf_sample_data *data, struct pt_regs *regs)
+{
+ struct perf_event_attr attr;
+
+ attr = bp->attr;
+ attr.disabled = true;
+ modify_user_hw_breakpoint(bp, &attr);
+}
+
+static int set_single_step(struct task_struct *tsk, unsigned long addr)
+{
+ struct perf_event *bp;
+ struct perf_event_attr attr;
+ struct arch_hw_breakpoint *info;
+ struct thread_struct *thread = &tsk->thread;
+
+ bp = thread->hbp_break[0];
+ if (!bp) {
+ ptrace_breakpoint_init(&attr);
+
+ attr.bp_addr = addr;
+ attr.bp_len = HW_BREAKPOINT_LEN_8;
+ attr.bp_type = HW_BREAKPOINT_X;
+
+ bp = register_user_hw_breakpoint(&attr, ptrace_triggered,
+ NULL, tsk);
+ if (IS_ERR(bp))
+ return PTR_ERR(bp);
+
+ thread->hbp_break[0] = bp;
+ } else {
+ int err;
+
+ attr = bp->attr;
+ attr.bp_addr = addr;
+
+ /* Reenable breakpoint */
+ attr.disabled = false;
+ err = modify_user_hw_breakpoint(bp, &attr);
+ if (unlikely(err))
+ return err;
+
+ csr_write64(attr.bp_addr, LOONGARCH_CSR_IB0ADDR);
+ }
+ info = counter_arch_bp(bp);
+ info->mask = TASK_SIZE - 1;
+
+ return 0;
+}
+
+/* ptrace API */
+void user_enable_single_step(struct task_struct *task)
+{
+ struct thread_info *ti = task_thread_info(task);
+
+ set_single_step(task, task_pt_regs(task)->csr_era);
+ task->thread.single_step = task_pt_regs(task)->csr_era;
+ set_ti_thread_flag(ti, TIF_SINGLESTEP);
+}
+
+void user_disable_single_step(struct task_struct *task)
+{
+ clear_tsk_thread_flag(task, TIF_SINGLESTEP);
+}
+#endif