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 32 #include <asm/user.h> 33 34 static int genregs_get(struct task_struct *target, 35 const struct user_regset *regset, 36 unsigned int pos, unsigned int count, 37 void *kbuf, void __user *ubuf) 38 { 39 int ret; 40 unsigned int dummy; 41 struct pt_regs *regs = task_pt_regs(target); 42 43 44 if (!regs) 45 return -EIO; 46 47 /* The general idea here is that the copyout must happen in 48 * exactly the same order in which the userspace expects these 49 * regs. Now, the sequence in userspace does not match the 50 * sequence in the kernel, so everything past the 32 gprs 51 * happens one at a time. 52 */ 53 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, 54 ®s->r00, 0, 32*sizeof(unsigned long)); 55 56 #define ONEXT(KPT_REG, USR_REG) \ 57 if (!ret) \ 58 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, \ 59 KPT_REG, offsetof(struct user_regs_struct, USR_REG), \ 60 offsetof(struct user_regs_struct, USR_REG) + \ 61 sizeof(unsigned long)); 62 63 /* Must be exactly same sequence as struct user_regs_struct */ 64 ONEXT(®s->sa0, sa0); 65 ONEXT(®s->lc0, lc0); 66 ONEXT(®s->sa1, sa1); 67 ONEXT(®s->lc1, lc1); 68 ONEXT(®s->m0, m0); 69 ONEXT(®s->m1, m1); 70 ONEXT(®s->usr, usr); 71 ONEXT(®s->preds, p3_0); 72 ONEXT(®s->gp, gp); 73 ONEXT(®s->ugp, ugp); 74 ONEXT(&pt_elr(regs), pc); 75 dummy = pt_cause(regs); 76 ONEXT(&dummy, cause); 77 ONEXT(&pt_badva(regs), badva); 78 79 /* Pad the rest with zeros, if needed */ 80 if (!ret) 81 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, 82 offsetof(struct user_regs_struct, pad1), -1); 83 return ret; 84 } 85 86 static int genregs_set(struct task_struct *target, 87 const struct user_regset *regset, 88 unsigned int pos, unsigned int count, 89 const void *kbuf, const void __user *ubuf) 90 { 91 int ret; 92 unsigned long bucket; 93 struct pt_regs *regs = task_pt_regs(target); 94 95 if (!regs) 96 return -EIO; 97 98 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, 99 ®s->r00, 0, 32*sizeof(unsigned long)); 100 101 #define INEXT(KPT_REG, USR_REG) \ 102 if (!ret) \ 103 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \ 104 KPT_REG, offsetof(struct user_regs_struct, USR_REG), \ 105 offsetof(struct user_regs_struct, USR_REG) + \ 106 sizeof(unsigned long)); 107 108 /* Must be exactly same sequence as struct user_regs_struct */ 109 INEXT(®s->sa0, sa0); 110 INEXT(®s->lc0, lc0); 111 INEXT(®s->sa1, sa1); 112 INEXT(®s->lc1, lc1); 113 INEXT(®s->m0, m0); 114 INEXT(®s->m1, m1); 115 INEXT(®s->usr, usr); 116 INEXT(®s->preds, p3_0); 117 INEXT(®s->gp, gp); 118 INEXT(®s->ugp, ugp); 119 INEXT(&pt_elr(regs), pc); 120 121 /* CAUSE and BADVA aren't writeable. */ 122 INEXT(&bucket, cause); 123 INEXT(&bucket, badva); 124 125 /* Ignore the rest, if needed */ 126 if (!ret) 127 ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 128 offsetof(struct user_regs_struct, pad1), -1); 129 130 if (ret) 131 return ret; 132 133 /* 134 * This is special; SP is actually restored by the VM via the 135 * special event record which is set by the special trap. 136 */ 137 regs->hvmer.vmpsp = regs->r29; 138 return 0; 139 } 140 141 enum hexagon_regset { 142 REGSET_GENERAL, 143 }; 144 145 static const struct user_regset hexagon_regsets[] = { 146 [REGSET_GENERAL] = { 147 .core_note_type = NT_PRSTATUS, 148 .n = ELF_NGREG, 149 .size = sizeof(unsigned long), 150 .align = sizeof(unsigned long), 151 .get = genregs_get, 152 .set = genregs_set, 153 }, 154 }; 155 156 static const struct user_regset_view hexagon_user_view = { 157 .name = UTS_MACHINE, 158 .e_machine = ELF_ARCH, 159 .ei_osabi = ELF_OSABI, 160 .regsets = hexagon_regsets, 161 .n = ARRAY_SIZE(hexagon_regsets) 162 }; 163 164 const struct user_regset_view *task_user_regset_view(struct task_struct *task) 165 { 166 return &hexagon_user_view; 167 } 168 169 void ptrace_disable(struct task_struct *child) 170 { 171 /* Boilerplate - resolves to null inline if no HW single-step */ 172 user_disable_single_step(child); 173 } 174 175 long arch_ptrace(struct task_struct *child, long request, 176 unsigned long addr, unsigned long data) 177 { 178 return ptrace_request(child, request, addr, data); 179 } 180