[PATCH 06/41] [ia64] regularize do_gpregs_[gs]et()

From: Al Viro
Date: Mon Jun 29 2020 - 17:26:08 EST


From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>

now access_elf_reg() does the right thing for everything other than
r0, we can simplify do_grepgs_[gs]et()

Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
arch/ia64/kernel/ptrace.c | 155 ++++++++++------------------------------------
1 file changed, 31 insertions(+), 124 deletions(-)

diff --git a/arch/ia64/kernel/ptrace.c b/arch/ia64/kernel/ptrace.c
index 37b5140d0dfe..be635f6f93c9 100644
--- a/arch/ia64/kernel/ptrace.c
+++ b/arch/ia64/kernel/ptrace.c
@@ -1491,10 +1491,7 @@ access_elf_reg(struct task_struct *target, struct unw_frame_info *info,

void do_gpregs_get(struct unw_frame_info *info, void *arg)
{
- struct pt_regs *pt;
struct regset_getset *dst = arg;
- elf_greg_t tmp[16];
- unsigned int i, index, min_copy;

if (unw_unwind_to_user(info) < 0)
return;
@@ -1517,160 +1514,70 @@ void do_gpregs_get(struct unw_frame_info *info, void *arg)
&dst->u.get.kbuf,
&dst->u.get.ubuf,
0, ELF_GR_OFFSET(1));
- if (dst->ret || dst->count == 0)
- return;
- }
-
- /* gr1 - gr15 */
- if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(16)) {
- index = (dst->pos - ELF_GR_OFFSET(1)) / sizeof(elf_greg_t);
- min_copy = ELF_GR_OFFSET(16) > (dst->pos + dst->count) ?
- (dst->pos + dst->count) : ELF_GR_OFFSET(16);
- for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t),
- index++)
- if (access_elf_reg(dst->target, info, i,
- &tmp[index], 0) < 0) {
- dst->ret = -EIO;
- return;
- }
- dst->ret = user_regset_copyout(&dst->pos, &dst->count,
- &dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
- ELF_GR_OFFSET(1), ELF_GR_OFFSET(16));
- if (dst->ret || dst->count == 0)
- return;
- }
-
- /* r16-r31 */
- if (dst->count > 0 && dst->pos < ELF_NAT_OFFSET) {
- pt = task_pt_regs(dst->target);
- dst->ret = user_regset_copyout(&dst->pos, &dst->count,
- &dst->u.get.kbuf, &dst->u.get.ubuf, &pt->r16,
- ELF_GR_OFFSET(16), ELF_NAT_OFFSET);
- if (dst->ret || dst->count == 0)
+ if (dst->ret)
return;
}

- /* nat, pr, b0 - b7 */
- if (dst->count > 0 && dst->pos < ELF_CR_IIP_OFFSET) {
- index = (dst->pos - ELF_NAT_OFFSET) / sizeof(elf_greg_t);
- min_copy = ELF_CR_IIP_OFFSET > (dst->pos + dst->count) ?
- (dst->pos + dst->count) : ELF_CR_IIP_OFFSET;
- for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t),
- index++)
- if (access_elf_reg(dst->target, info, i,
- &tmp[index], 0) < 0) {
+ while (dst->count && dst->pos < ELF_AR_END_OFFSET) {
+ unsigned int n, from, to;
+ elf_greg_t tmp[16];
+
+ from = dst->pos;
+ to = from + min(dst->count, (unsigned)sizeof(tmp));
+ if (to > ELF_AR_END_OFFSET)
+ to = ELF_AR_END_OFFSET;
+ for (n = 0; from < to; from += sizeof(elf_greg_t), n++) {
+ if (access_elf_reg(dst->target, info, from,
+ &tmp[n], 0) < 0) {
dst->ret = -EIO;
return;
}
+ }
dst->ret = user_regset_copyout(&dst->pos, &dst->count,
&dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
- ELF_NAT_OFFSET, ELF_CR_IIP_OFFSET);
- if (dst->ret || dst->count == 0)
+ dst->pos, to);
+ if (dst->ret)
return;
}
-
- /* ip cfm psr ar.rsc ar.bsp ar.bspstore ar.rnat
- * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec ar.csd ar.ssd
- */
- if (dst->count > 0 && dst->pos < (ELF_AR_END_OFFSET)) {
- index = (dst->pos - ELF_CR_IIP_OFFSET) / sizeof(elf_greg_t);
- min_copy = ELF_AR_END_OFFSET > (dst->pos + dst->count) ?
- (dst->pos + dst->count) : ELF_AR_END_OFFSET;
- for (i = dst->pos; i < min_copy; i += sizeof(elf_greg_t),
- index++)
- if (access_elf_reg(dst->target, info, i,
- &tmp[index], 0) < 0) {
- dst->ret = -EIO;
- return;
- }
- dst->ret = user_regset_copyout(&dst->pos, &dst->count,
- &dst->u.get.kbuf, &dst->u.get.ubuf, tmp,
- ELF_CR_IIP_OFFSET, ELF_AR_END_OFFSET);
- }
}

void do_gpregs_set(struct unw_frame_info *info, void *arg)
{
- struct pt_regs *pt;
struct regset_getset *dst = arg;
- elf_greg_t tmp[16];
- unsigned int i, index;

if (unw_unwind_to_user(info) < 0)
return;

+ if (!dst->count)
+ return;
/* Skip r0 */
- if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(1)) {
+ if (dst->pos < ELF_GR_OFFSET(1)) {
dst->ret = user_regset_copyin_ignore(&dst->pos, &dst->count,
&dst->u.set.kbuf,
&dst->u.set.ubuf,
0, ELF_GR_OFFSET(1));
- if (dst->ret || dst->count == 0)
- return;
- }
-
- /* gr1-gr15 */
- if (dst->count > 0 && dst->pos < ELF_GR_OFFSET(16)) {
- i = dst->pos;
- index = (dst->pos - ELF_GR_OFFSET(1)) / sizeof(elf_greg_t);
- dst->ret = user_regset_copyin(&dst->pos, &dst->count,
- &dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
- ELF_GR_OFFSET(1), ELF_GR_OFFSET(16));
if (dst->ret)
return;
- for ( ; i < dst->pos; i += sizeof(elf_greg_t), index++)
- if (access_elf_reg(dst->target, info, i,
- &tmp[index], 1) < 0) {
- dst->ret = -EIO;
- return;
- }
- if (dst->count == 0)
- return;
- }
-
- /* gr16-gr31 */
- if (dst->count > 0 && dst->pos < ELF_NAT_OFFSET) {
- pt = task_pt_regs(dst->target);
- dst->ret = user_regset_copyin(&dst->pos, &dst->count,
- &dst->u.set.kbuf, &dst->u.set.ubuf, &pt->r16,
- ELF_GR_OFFSET(16), ELF_NAT_OFFSET);
- if (dst->ret || dst->count == 0)
- return;
}

- /* nat, pr, b0 - b7 */
- if (dst->count > 0 && dst->pos < ELF_CR_IIP_OFFSET) {
- i = dst->pos;
- index = (dst->pos - ELF_NAT_OFFSET) / sizeof(elf_greg_t);
- dst->ret = user_regset_copyin(&dst->pos, &dst->count,
- &dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
- ELF_NAT_OFFSET, ELF_CR_IIP_OFFSET);
- if (dst->ret)
- return;
- for (; i < dst->pos; i += sizeof(elf_greg_t), index++)
- if (access_elf_reg(dst->target, info, i,
- &tmp[index], 1) < 0) {
- dst->ret = -EIO;
- return;
- }
- if (dst->count == 0)
- return;
- }
+ while (dst->count && dst->pos < ELF_AR_END_OFFSET) {
+ unsigned int n, from, to;
+ elf_greg_t tmp[16];

- /* ip cfm psr ar.rsc ar.bsp ar.bspstore ar.rnat
- * ar.ccv ar.unat ar.fpsr ar.pfs ar.lc ar.ec ar.csd ar.ssd
- */
- if (dst->count > 0 && dst->pos < (ELF_AR_END_OFFSET)) {
- i = dst->pos;
- index = (dst->pos - ELF_CR_IIP_OFFSET) / sizeof(elf_greg_t);
+ from = dst->pos;
+ to = from + sizeof(tmp);
+ if (to > ELF_AR_END_OFFSET)
+ to = ELF_AR_END_OFFSET;
+ /* get up to 16 values */
dst->ret = user_regset_copyin(&dst->pos, &dst->count,
&dst->u.set.kbuf, &dst->u.set.ubuf, tmp,
- ELF_CR_IIP_OFFSET, ELF_AR_END_OFFSET);
+ from, to);
if (dst->ret)
return;
- for ( ; i < dst->pos; i += sizeof(elf_greg_t), index++)
- if (access_elf_reg(dst->target, info, i,
- &tmp[index], 1) < 0) {
+ /* now copy them into registers */
+ for (n = 0; from < dst->pos; from += sizeof(elf_greg_t), n++)
+ if (access_elf_reg(dst->target, info, from,
+ &tmp[n], 1) < 0) {
dst->ret = -EIO;
return;
}
--
2.11.0