1 /* 2 * Ptrace support for Hexagon 3 * 4 * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved. 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 and 8 * only version 2 as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 18 * 02110-1301, USA. 19 */ 20 21 #include <generated/compile.h> 22 23 #include <linux/kernel.h> 24 #include <linux/sched.h> 25 #include <linux/mm.h> 26 #include <linux/smp.h> 27 #include <linux/errno.h> 28 #include <linux/ptrace.h> 29 #include <linux/regset.h> 30 #include <linux/user.h> 31 #include <linux/elf.h> 32 33 #include <asm/user.h> 34 35 static int genregs_get(struct task_struct *target, 36 const struct user_regset *regset, 37 unsigned int pos, unsigned int count, 38 void *kbuf, void __user *ubuf) 39 { 40 int ret; 41 unsigned int dummy; 42 struct pt_regs *regs = task_pt_regs(target); 43 44 45 if (!regs) 46 return -EIO; 47 48 /* The general idea here is that the copyout must happen in 49 * exactly the same order in which the userspace expects these 50 * regs. Now, the sequence in userspace does not match the 51 * sequence in the kernel, so everything past the 32 gprs 52 * happens one at a time. 53 */ 54 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, 55 ®s->r00, 0, 32*sizeof(unsigned long)); 56 57 #define ONEXT(KPT_REG, USR_REG) \ 58 if (!ret) \ 59 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, \ 60 KPT_REG, offsetof(struct user_regs_struct, USR_REG), \ 61 offsetof(struct user_regs_struct, USR_REG) + \ 62 sizeof(unsigned long)); 63 64 /* Must be exactly same sequence as struct user_regs_struct */ 65 ONEXT(®s->sa0, sa0); 66 ONEXT(®s->lc0, lc0); 67 ONEXT(®s->sa1, sa1); 68 ONEXT(®s->lc1, lc1); 69 ONEXT(®s->m0, m0); 70 ONEXT(®s->m1, m1); 71 ONEXT(®s->usr, usr); 72 ONEXT(®s->preds, p3_0); 73 ONEXT(®s->gp, gp); 74 ONEXT(®s->ugp, ugp); 75 ONEXT(&pt_elr(regs), pc); 76 dummy = pt_cause(regs); 77 ONEXT(&dummy, cause); 78 ONEXT(&pt_badva(regs), badva); 79 80 /* Pad the rest with zeros, if needed */ 81 if (!ret) 82 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, 83 offsetof(struct user_regs_struct, pad1), -1); 84 return ret; 85 } 86 87 static int genregs_set(struct task_struct *target, 88 const struct user_regset *regset, 89 unsigned int pos, unsigned int count, 90 const void *kbuf, const void __user *ubuf) 91 { 92 int ret; 93 unsigned long bucket; 94 struct pt_regs *regs = task_pt_regs(target); 95 96 if (!regs) 97 return -EIO; 98 99 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, 100 ®s->r00, 0, 32*sizeof(unsigned long)); 101 102 #define INEXT(KPT_REG, USR_REG) \ 103 if (!ret) \ 104 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \ 105 KPT_REG, offsetof(struct user_regs_struct, USR_REG), \ 106 offsetof(struct user_regs_struct, USR_REG) + \ 107 sizeof(unsigned long)); 108 109 /* Must be exactly same sequence as struct user_regs_struct */ 110 INEXT(®s->sa0, sa0); 111 INEXT(®s->lc0, lc0); 112 INEXT(®s->sa1, sa1); 113 INEXT(®s->lc1, lc1); 114 INEXT(®s->m0, m0); 115 INEXT(®s->m1, m1); 116 INEXT(®s->usr, usr); 117 INEXT(®s->preds, p3_0); 118 INEXT(®s->gp, gp); 119 INEXT(®s->ugp, ugp); 120 INEXT(&pt_elr(regs), pc); 121 122 /* CAUSE and BADVA aren't writeable. */ 123 INEXT(&bucket, cause); 124 INEXT(&bucket, badva); 125 126 /* Ignore the rest, if needed */ 127 if (!ret) 128 ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 129 offsetof(struct user_regs_struct, pad1), -1); 130 131 if (ret) 132 return ret; 133 134 /* 135 * This is special; SP is actually restored by the VM via the 136 * special event record which is set by the special trap. 137 */ 138 regs->hvmer.vmpsp = regs->r29; 139 return 0; 140 } 141 142 enum hexagon_regset { 143 REGSET_GENERAL, 144 }; 145 146 static const struct user_regset hexagon_regsets[] = { 147 [REGSET_GENERAL] = { 148 .core_note_type = NT_PRSTATUS, 149 .n = ELF_NGREG, 150 .size = sizeof(unsigned long), 151 .align = sizeof(unsigned long), 152 .get = genregs_get, 153 .set = genregs_set, 154 }, 155 }; 156 157 static const struct user_regset_view hexagon_user_view = { 158 .name = UTS_MACHINE, 159 .e_machine = ELF_ARCH, 160 .ei_osabi = ELF_OSABI, 161 .regsets = hexagon_regsets, 162 .n = ARRAY_SIZE(hexagon_regsets) 163 }; 164 165 const struct user_regset_view *task_user_regset_view(struct task_struct *task) 166 { 167 return &hexagon_user_view; 168 } 169 170 void ptrace_disable(struct task_struct *child) 171 { 172 /* Boilerplate - resolves to null inline if no HW single-step */ 173 user_disable_single_step(child); 174 } 175 176 long arch_ptrace(struct task_struct *child, long request, 177 unsigned long addr, unsigned long data) 178 { 179 return ptrace_request(child, request, addr, data); 180 } 181