diff options
author | K.Prasad <prasad@linux.vnet.ibm.com> | 2012-10-28 11:13:15 -0400 |
---|---|---|
committer | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2012-11-14 21:00:23 -0500 |
commit | 6c7a2856ade6a58c20038024247d16a12a8d2323 (patch) | |
tree | 87d43dc2aeaded2c7d9cc9faaa2ce326334f2360 /arch/powerpc/kernel | |
parent | 16b86bf2520ed29712ca7462dbfe76c856b445e9 (diff) |
powerpc/hw-breakpoint: Use generic hw-breakpoint interfaces for new PPC ptrace flags
PPC_PTRACE_GETHWDBGINFO, PPC_PTRACE_SETHWDEBUG and PPC_PTRACE_DELHWDEBUG are
PowerPC specific ptrace flags that use the watchpoint register. While they are
targeted primarily towards BookE users, user-space applications such as GDB
have started using them for BookS too. This patch enables the use of generic
hardware breakpoint interfaces for these new flags.
Apart from the usual benefits of using generic hw-breakpoint interfaces, these
changes allow debuggers (such as GDB) to use a common set of ptrace flags for
their watchpoint needs and allow more precise breakpoint specification (length
of the variable can be specified).
Mikey added: rebased and added dbginfo.features around #ifdef
CONFIG_HAVE_HW_BREAKPOINT
Signed-off-by: K.Prasad <prasad@linux.vnet.ibm.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/kernel')
-rw-r--r-- | arch/powerpc/kernel/ptrace.c | 78 |
1 files changed, 74 insertions, 4 deletions
diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c index 79d8e56470df..140238aad718 100644 --- a/arch/powerpc/kernel/ptrace.c +++ b/arch/powerpc/kernel/ptrace.c | |||
@@ -1338,6 +1338,12 @@ static int set_dac_range(struct task_struct *child, | |||
1338 | static long ppc_set_hwdebug(struct task_struct *child, | 1338 | static long ppc_set_hwdebug(struct task_struct *child, |
1339 | struct ppc_hw_breakpoint *bp_info) | 1339 | struct ppc_hw_breakpoint *bp_info) |
1340 | { | 1340 | { |
1341 | #ifdef CONFIG_HAVE_HW_BREAKPOINT | ||
1342 | int len = 0; | ||
1343 | struct thread_struct *thread = &(child->thread); | ||
1344 | struct perf_event *bp; | ||
1345 | struct perf_event_attr attr; | ||
1346 | #endif /* CONFIG_HAVE_HW_BREAKPOINT */ | ||
1341 | #ifndef CONFIG_PPC_ADV_DEBUG_REGS | 1347 | #ifndef CONFIG_PPC_ADV_DEBUG_REGS |
1342 | unsigned long dabr; | 1348 | unsigned long dabr; |
1343 | #endif | 1349 | #endif |
@@ -1381,13 +1387,9 @@ static long ppc_set_hwdebug(struct task_struct *child, | |||
1381 | */ | 1387 | */ |
1382 | if ((bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_RW) == 0 || | 1388 | if ((bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_RW) == 0 || |
1383 | (bp_info->trigger_type & ~PPC_BREAKPOINT_TRIGGER_RW) != 0 || | 1389 | (bp_info->trigger_type & ~PPC_BREAKPOINT_TRIGGER_RW) != 0 || |
1384 | bp_info->addr_mode != PPC_BREAKPOINT_MODE_EXACT || | ||
1385 | bp_info->condition_mode != PPC_BREAKPOINT_CONDITION_NONE) | 1390 | bp_info->condition_mode != PPC_BREAKPOINT_CONDITION_NONE) |
1386 | return -EINVAL; | 1391 | return -EINVAL; |
1387 | 1392 | ||
1388 | if (child->thread.dabr) | ||
1389 | return -ENOSPC; | ||
1390 | |||
1391 | if ((unsigned long)bp_info->addr >= TASK_SIZE) | 1393 | if ((unsigned long)bp_info->addr >= TASK_SIZE) |
1392 | return -EIO; | 1394 | return -EIO; |
1393 | 1395 | ||
@@ -1397,6 +1399,50 @@ static long ppc_set_hwdebug(struct task_struct *child, | |||
1397 | dabr |= DABR_DATA_READ; | 1399 | dabr |= DABR_DATA_READ; |
1398 | if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_WRITE) | 1400 | if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_WRITE) |
1399 | dabr |= DABR_DATA_WRITE; | 1401 | dabr |= DABR_DATA_WRITE; |
1402 | #ifdef CONFIG_HAVE_HW_BREAKPOINT | ||
1403 | if (ptrace_get_breakpoints(child) < 0) | ||
1404 | return -ESRCH; | ||
1405 | |||
1406 | /* | ||
1407 | * Check if the request is for 'range' breakpoints. We can | ||
1408 | * support it if range < 8 bytes. | ||
1409 | */ | ||
1410 | if (bp_info->addr_mode == PPC_BREAKPOINT_MODE_RANGE_INCLUSIVE) { | ||
1411 | len = bp_info->addr2 - bp_info->addr; | ||
1412 | } else if (bp_info->addr_mode != PPC_BREAKPOINT_MODE_EXACT) { | ||
1413 | ptrace_put_breakpoints(child); | ||
1414 | return -EINVAL; | ||
1415 | } | ||
1416 | bp = thread->ptrace_bps[0]; | ||
1417 | if (bp) { | ||
1418 | ptrace_put_breakpoints(child); | ||
1419 | return -ENOSPC; | ||
1420 | } | ||
1421 | |||
1422 | /* Create a new breakpoint request if one doesn't exist already */ | ||
1423 | hw_breakpoint_init(&attr); | ||
1424 | attr.bp_addr = (unsigned long)bp_info->addr & ~HW_BREAKPOINT_ALIGN; | ||
1425 | attr.bp_len = len; | ||
1426 | arch_bp_generic_fields(dabr & (DABR_DATA_WRITE | DABR_DATA_READ), | ||
1427 | &attr.bp_type); | ||
1428 | |||
1429 | thread->ptrace_bps[0] = bp = register_user_hw_breakpoint(&attr, | ||
1430 | ptrace_triggered, NULL, child); | ||
1431 | if (IS_ERR(bp)) { | ||
1432 | thread->ptrace_bps[0] = NULL; | ||
1433 | ptrace_put_breakpoints(child); | ||
1434 | return PTR_ERR(bp); | ||
1435 | } | ||
1436 | |||
1437 | ptrace_put_breakpoints(child); | ||
1438 | return 1; | ||
1439 | #endif /* CONFIG_HAVE_HW_BREAKPOINT */ | ||
1440 | |||
1441 | if (bp_info->addr_mode != PPC_BREAKPOINT_MODE_EXACT) | ||
1442 | return -EINVAL; | ||
1443 | |||
1444 | if (child->thread.dabr) | ||
1445 | return -ENOSPC; | ||
1400 | 1446 | ||
1401 | child->thread.dabr = dabr; | 1447 | child->thread.dabr = dabr; |
1402 | child->thread.dabrx = DABRX_ALL; | 1448 | child->thread.dabrx = DABRX_ALL; |
@@ -1407,6 +1453,11 @@ static long ppc_set_hwdebug(struct task_struct *child, | |||
1407 | 1453 | ||
1408 | static long ppc_del_hwdebug(struct task_struct *child, long addr, long data) | 1454 | static long ppc_del_hwdebug(struct task_struct *child, long addr, long data) |
1409 | { | 1455 | { |
1456 | #ifdef CONFIG_HAVE_HW_BREAKPOINT | ||
1457 | int ret = 0; | ||
1458 | struct thread_struct *thread = &(child->thread); | ||
1459 | struct perf_event *bp; | ||
1460 | #endif /* CONFIG_HAVE_HW_BREAKPOINT */ | ||
1410 | #ifdef CONFIG_PPC_ADV_DEBUG_REGS | 1461 | #ifdef CONFIG_PPC_ADV_DEBUG_REGS |
1411 | int rc; | 1462 | int rc; |
1412 | 1463 | ||
@@ -1426,10 +1477,25 @@ static long ppc_del_hwdebug(struct task_struct *child, long addr, long data) | |||
1426 | #else | 1477 | #else |
1427 | if (data != 1) | 1478 | if (data != 1) |
1428 | return -EINVAL; | 1479 | return -EINVAL; |
1480 | |||
1481 | #ifdef CONFIG_HAVE_HW_BREAKPOINT | ||
1482 | if (ptrace_get_breakpoints(child) < 0) | ||
1483 | return -ESRCH; | ||
1484 | |||
1485 | bp = thread->ptrace_bps[0]; | ||
1486 | if (bp) { | ||
1487 | unregister_hw_breakpoint(bp); | ||
1488 | thread->ptrace_bps[0] = NULL; | ||
1489 | } else | ||
1490 | ret = -ENOENT; | ||
1491 | ptrace_put_breakpoints(child); | ||
1492 | return ret; | ||
1493 | #else /* CONFIG_HAVE_HW_BREAKPOINT */ | ||
1429 | if (child->thread.dabr == 0) | 1494 | if (child->thread.dabr == 0) |
1430 | return -ENOENT; | 1495 | return -ENOENT; |
1431 | 1496 | ||
1432 | child->thread.dabr = 0; | 1497 | child->thread.dabr = 0; |
1498 | #endif /* CONFIG_HAVE_HW_BREAKPOINT */ | ||
1433 | 1499 | ||
1434 | return 0; | 1500 | return 0; |
1435 | #endif | 1501 | #endif |
@@ -1536,7 +1602,11 @@ long arch_ptrace(struct task_struct *child, long request, | |||
1536 | dbginfo.data_bp_alignment = 4; | 1602 | dbginfo.data_bp_alignment = 4; |
1537 | #endif | 1603 | #endif |
1538 | dbginfo.sizeof_condition = 0; | 1604 | dbginfo.sizeof_condition = 0; |
1605 | #ifdef CONFIG_HAVE_HW_BREAKPOINT | ||
1606 | dbginfo.features = PPC_DEBUG_FEATURE_DATA_BP_RANGE; | ||
1607 | #else | ||
1539 | dbginfo.features = 0; | 1608 | dbginfo.features = 0; |
1609 | #endif /* CONFIG_HAVE_HW_BREAKPOINT */ | ||
1540 | #endif /* CONFIG_PPC_ADV_DEBUG_REGS */ | 1610 | #endif /* CONFIG_PPC_ADV_DEBUG_REGS */ |
1541 | 1611 | ||
1542 | if (!access_ok(VERIFY_WRITE, datavp, | 1612 | if (!access_ok(VERIFY_WRITE, datavp, |