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Merge branch 'tracing/mmiotrace' into auto-ftrace-next

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This commit is contained in:
Ingo Molnar 2008-07-10 11:43:06 +02:00
commit 5373fdbdc1
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164
Documentation/tracers/mmiotrace.txt Normal file
View File

@ -0,0 +1,164 @@
In-kernel memory-mapped I/O tracing
Home page and links to optional user space tools:
http://nouveau.freedesktop.org/wiki/MmioTrace
MMIO tracing was originally developed by Intel around 2003 for their Fault
Injection Test Harness. In Dec 2006 - Jan 2007, using the code from Intel,
Jeff Muizelaar created a tool for tracing MMIO accesses with the Nouveau
project in mind. Since then many people have contributed.
Mmiotrace was built for reverse engineering any memory-mapped IO device with
the Nouveau project as the first real user. Only x86 and x86_64 architectures
are supported.
Out-of-tree mmiotrace was originally modified for mainline inclusion and
ftrace framework by Pekka Paalanen <pq@iki.fi>.
Preparation
-----------
Mmiotrace feature is compiled in by the CONFIG_MMIOTRACE option. Tracing is
disabled by default, so it is safe to have this set to yes. SMP systems are
supported, but tracing is unreliable and may miss events if more than one CPU
is on-line, therefore mmiotrace takes all but one CPU off-line during run-time
activation. You can re-enable CPUs by hand, but you have been warned, there
is no way to automatically detect if you are losing events due to CPUs racing.
Usage Quick Reference
---------------------
$ mount -t debugfs debugfs /debug
$ echo mmiotrace > /debug/tracing/current_tracer
$ cat /debug/tracing/trace_pipe > mydump.txt &
Start X or whatever.
$ echo "X is up" > /debug/tracing/marker
$ echo none > /debug/tracing/current_tracer
Check for lost events.
Usage
-----
Make sure debugfs is mounted to /debug. If not, (requires root privileges)
$ mount -t debugfs debugfs /debug
Check that the driver you are about to trace is not loaded.
Activate mmiotrace (requires root privileges):
$ echo mmiotrace > /debug/tracing/current_tracer
Start storing the trace:
$ cat /debug/tracing/trace_pipe > mydump.txt &
The 'cat' process should stay running (sleeping) in the background.
Load the driver you want to trace and use it. Mmiotrace will only catch MMIO
accesses to areas that are ioremapped while mmiotrace is active.
[Unimplemented feature:]
During tracing you can place comments (markers) into the trace by
$ echo "X is up" > /debug/tracing/marker
This makes it easier to see which part of the (huge) trace corresponds to
which action. It is recommended to place descriptive markers about what you
do.
Shut down mmiotrace (requires root privileges):
$ echo none > /debug/tracing/current_tracer
The 'cat' process exits. If it does not, kill it by issuing 'fg' command and
pressing ctrl+c.
Check that mmiotrace did not lose events due to a buffer filling up. Either
$ grep -i lost mydump.txt
which tells you exactly how many events were lost, or use
$ dmesg
to view your kernel log and look for "mmiotrace has lost events" warning. If
events were lost, the trace is incomplete. You should enlarge the buffers and
try again. Buffers are enlarged by first seeing how large the current buffers
are:
$ cat /debug/tracing/trace_entries
gives you a number. Approximately double this number and write it back, for
instance:
$ echo 128000 > /debug/tracing/trace_entries
Then start again from the top.
If you are doing a trace for a driver project, e.g. Nouveau, you should also
do the following before sending your results:
$ lspci -vvv > lspci.txt
$ dmesg > dmesg.txt
$ tar zcf pciid-nick-mmiotrace.tar.gz mydump.txt lspci.txt dmesg.txt
and then send the .tar.gz file. The trace compresses considerably. Replace
"pciid" and "nick" with the PCI ID or model name of your piece of hardware
under investigation and your nick name.
How Mmiotrace Works
-------------------
Access to hardware IO-memory is gained by mapping addresses from PCI bus by
calling one of the ioremap_*() functions. Mmiotrace is hooked into the
__ioremap() function and gets called whenever a mapping is created. Mapping is
an event that is recorded into the trace log. Note, that ISA range mappings
are not caught, since the mapping always exists and is returned directly.
MMIO accesses are recorded via page faults. Just before __ioremap() returns,
the mapped pages are marked as not present. Any access to the pages causes a
fault. The page fault handler calls mmiotrace to handle the fault. Mmiotrace
marks the page present, sets TF flag to achieve single stepping and exits the
fault handler. The instruction that faulted is executed and debug trap is
entered. Here mmiotrace again marks the page as not present. The instruction
is decoded to get the type of operation (read/write), data width and the value
read or written. These are stored to the trace log.
Setting the page present in the page fault handler has a race condition on SMP
machines. During the single stepping other CPUs may run freely on that page
and events can be missed without a notice. Re-enabling other CPUs during
tracing is discouraged.
Trace Log Format
----------------
The raw log is text and easily filtered with e.g. grep and awk. One record is
one line in the log. A record starts with a keyword, followed by keyword
dependant arguments. Arguments are separated by a space, or continue until the
end of line. The format for version 20070824 is as follows:
Explanation Keyword Space separated arguments
---------------------------------------------------------------------------
read event R width, timestamp, map id, physical, value, PC, PID
write event W width, timestamp, map id, physical, value, PC, PID
ioremap event MAP timestamp, map id, physical, virtual, length, PC, PID
iounmap event UNMAP timestamp, map id, PC, PID
marker MARK timestamp, text
version VERSION the string "20070824"
info for reader LSPCI one line from lspci -v
PCI address map PCIDEV space separated /proc/bus/pci/devices data
unk. opcode UNKNOWN timestamp, map id, physical, data, PC, PID
Timestamp is in seconds with decimals. Physical is a PCI bus address, virtual
is a kernel virtual address. Width is the data width in bytes and value is the
data value. Map id is an arbitrary id number identifying the mapping that was
used in an operation. PC is the program counter and PID is process id. PC is
zero if it is not recorded. PID is always zero as tracing MMIO accesses
originating in user space memory is not yet supported.
For instance, the following awk filter will pass all 32-bit writes that target
physical addresses in the range [0xfb73ce40, 0xfb800000[
$ awk '/W 4 / { adr=strtonum($5); if (adr >= 0xfb73ce40 &&
adr < 0xfb800000) print; }'
Tools for Developers
--------------------
The user space tools include utilities for:
- replacing numeric addresses and values with hardware register names
- replaying MMIO logs, i.e., re-executing the recorded writes

32
arch/x86/Kconfig.debug
View File

@ -172,13 +172,33 @@ config IOMMU_LEAK
Add a simple leak tracer to the IOMMU code. This is useful when you
are debugging a buggy device driver that leaks IOMMU mappings.
config PAGE_FAULT_HANDLERS
bool "Custom page fault handlers"
depends on DEBUG_KERNEL
config MMIOTRACE_HOOKS
bool
config MMIOTRACE
bool "Memory mapped IO tracing"
depends on DEBUG_KERNEL && PCI
select TRACING
select MMIOTRACE_HOOKS
default y
help
Allow the use of custom page fault handlers. A kernel module may
register a function that is called on every page fault. Custom
handlers are used by some debugging and reverse engineering tools.
Mmiotrace traces Memory Mapped I/O access and is meant for
debugging and reverse engineering. It is called from the ioremap
implementation and works via page faults. Tracing is disabled by
default and can be enabled at run-time.
See Documentation/tracers/mmiotrace.txt.
If you are not helping to develop drivers, say N.
config MMIOTRACE_TEST
tristate "Test module for mmiotrace"
depends on MMIOTRACE && m
help
This is a dumb module for testing mmiotrace. It is very dangerous
as it will write garbage to IO memory starting at a given address.
However, it should be safe to use on e.g. unused portion of VRAM.
Say N, unless you absolutely know what you are doing.
#
# IO delay types:

5
arch/x86/mm/Makefile
View File

@ -8,6 +8,11 @@ obj-$(CONFIG_X86_PTDUMP) += dump_pagetables.o
obj-$(CONFIG_HIGHMEM) += highmem_32.o
obj-$(CONFIG_MMIOTRACE_HOOKS) += kmmio.o
obj-$(CONFIG_MMIOTRACE) += mmiotrace.o
mmiotrace-y := pf_in.o mmio-mod.o
obj-$(CONFIG_MMIOTRACE_TEST) += testmmiotrace.o
ifeq ($(CONFIG_X86_32),y)
obj-$(CONFIG_NUMA) += discontig_32.o
else

57
arch/x86/mm/fault.c
View File

@ -10,6 +10,7 @@
#include <linux/string.h>
#include <linux/types.h>
#include <linux/ptrace.h>
#include <linux/mmiotrace.h>
#include <linux/mman.h>
#include <linux/mm.h>
#include <linux/smp.h>
@ -49,58 +50,14 @@
#define PF_RSVD (1<<3)
#define PF_INSTR (1<<4)
#ifdef CONFIG_PAGE_FAULT_HANDLERS
static HLIST_HEAD(pf_handlers); /* protected by RCU */
static DEFINE_SPINLOCK(pf_handlers_writer);
void register_page_fault_handler(struct pf_handler *new_pfh)
static inline int kmmio_fault(struct pt_regs *regs, unsigned long addr)
{
unsigned long flags;
spin_lock_irqsave(&pf_handlers_writer, flags);
hlist_add_head_rcu(&new_pfh->hlist, &pf_handlers);
spin_unlock_irqrestore(&pf_handlers_writer, flags);
}
EXPORT_SYMBOL_GPL(register_page_fault_handler);
/**
* unregister_page_fault_handler:
* The caller must ensure @old_pfh is not in use anymore before freeing it.
* This function does not guarantee it. The list of handlers is protected by
* RCU, so you can do this by e.g. calling synchronize_rcu().
*/
void unregister_page_fault_handler(struct pf_handler *old_pfh)
{
unsigned long flags;
spin_lock_irqsave(&pf_handlers_writer, flags);
hlist_del_rcu(&old_pfh->hlist);
spin_unlock_irqrestore(&pf_handlers_writer, flags);
}
EXPORT_SYMBOL_GPL(unregister_page_fault_handler);
#ifdef CONFIG_MMIOTRACE_HOOKS
if (unlikely(is_kmmio_active()))
if (kmmio_handler(regs, addr) == 1)
return -1;
#endif
/* returns non-zero if do_page_fault() should return */
static int handle_custom_pf(struct pt_regs *regs, unsigned long error_code,
unsigned long address)
{
#ifdef CONFIG_PAGE_FAULT_HANDLERS
int ret = 0;
struct pf_handler *cur;
struct hlist_node *ncur;
if (hlist_empty(&pf_handlers))
return 0;
rcu_read_lock();
hlist_for_each_entry_rcu(cur, ncur, &pf_handlers, hlist) {
ret = cur->handler(regs, error_code, address);
if (ret)
break;
}
rcu_read_unlock();
return ret;
#else
return 0;
#endif
}
static inline int notify_page_fault(struct pt_regs *regs)
@ -660,7 +617,7 @@ void __kprobes do_page_fault(struct pt_regs *regs, unsigned long error_code)
if (notify_page_fault(regs))
return;
if (handle_custom_pf(regs, error_code, address))
if (unlikely(kmmio_fault(regs, address)))
return;
/*

11
arch/x86/mm/ioremap.c
View File

@ -12,6 +12,7 @@
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/mmiotrace.h>
#include <asm/cacheflush.h>
#include <asm/e820.h>
@ -122,10 +123,13 @@ static void __iomem *__ioremap_caller(resource_size_t phys_addr,
{
unsigned long pfn, offset, vaddr;
resource_size_t last_addr;
const resource_size_t unaligned_phys_addr = phys_addr;
const unsigned long unaligned_size = size;
struct vm_struct *area;
unsigned long new_prot_val;
pgprot_t prot;
int retval;
void __iomem *ret_addr;
/* Don't allow wraparound or zero size */
last_addr = phys_addr + size - 1;
@ -233,7 +237,10 @@ static void __iomem *__ioremap_caller(resource_size_t phys_addr,
return NULL;
}
return (void __iomem *) (vaddr + offset);
ret_addr = (void __iomem *) (vaddr + offset);
mmiotrace_ioremap(unaligned_phys_addr, unaligned_size, ret_addr);
return ret_addr;
}
/**
@ -325,6 +332,8 @@ void iounmap(volatile void __iomem *addr)
addr = (volatile void __iomem *)
(PAGE_MASK & (unsigned long __force)addr);
mmiotrace_iounmap(addr);
/* Use the vm area unlocked, assuming the caller
ensures there isn't another iounmap for the same address
in parallel. Reuse of the virtual address is prevented by

510
arch/x86/mm/kmmio.c Normal file
View File

@ -0,0 +1,510 @@
/* Support for MMIO probes.
* Benfit many code from kprobes
* (C) 2002 Louis Zhuang <louis.zhuang@intel.com>.
* 2007 Alexander Eichner
* 2008 Pekka Paalanen <pq@iki.fi>
*/
#include <linux/list.h>
#include <linux/rculist.h>
#include <linux/spinlock.h>
#include <linux/hash.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/uaccess.h>
#include <linux/ptrace.h>
#include <linux/preempt.h>
#include <linux/percpu.h>
#include <linux/kdebug.h>
#include <linux/mutex.h>
#include <linux/io.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
#include <linux/errno.h>
#include <asm/debugreg.h>
#include <linux/mmiotrace.h>
#define KMMIO_PAGE_HASH_BITS 4
#define KMMIO_PAGE_TABLE_SIZE (1 << KMMIO_PAGE_HASH_BITS)
struct kmmio_fault_page {
struct list_head list;
struct kmmio_fault_page *release_next;
unsigned long page; /* location of the fault page */
/*
* Number of times this page has been registered as a part
* of a probe. If zero, page is disarmed and this may be freed.
* Used only by writers (RCU).
*/
int count;
};
struct kmmio_delayed_release {
struct rcu_head rcu;
struct kmmio_fault_page *release_list;
};
struct kmmio_context {
struct kmmio_fault_page *fpage;
struct kmmio_probe *probe;
unsigned long saved_flags;
unsigned long addr;
int active;
};
static DEFINE_SPINLOCK(kmmio_lock);
/* Protected by kmmio_lock */
unsigned int kmmio_count;
/* Read-protected by RCU, write-protected by kmmio_lock. */
static struct list_head kmmio_page_table[KMMIO_PAGE_TABLE_SIZE];
static LIST_HEAD(kmmio_probes);
static struct list_head *kmmio_page_list(unsigned long page)
{
return &kmmio_page_table[hash_long(page, KMMIO_PAGE_HASH_BITS)];
}
/* Accessed per-cpu */
static DEFINE_PER_CPU(struct kmmio_context, kmmio_ctx);
/*
* this is basically a dynamic stabbing problem:
* Could use the existing prio tree code or
* Possible better implementations:
* The Interval Skip List: A Data Structure for Finding All Intervals That
* Overlap a Point (might be simple)
* Space Efficient Dynamic Stabbing with Fast Queries - Mikkel Thorup
*/
/* Get the kmmio at this addr (if any). You must be holding RCU read lock. */
static struct kmmio_probe *get_kmmio_probe(unsigned long addr)
{
struct kmmio_probe *p;
list_for_each_entry_rcu(p, &kmmio_probes, list) {
if (addr >= p->addr && addr <= (p->addr + p->len))
return p;
}
return NULL;
}
/* You must be holding RCU read lock. */
static struct kmmio_fault_page *get_kmmio_fault_page(unsigned long page)
{
struct list_head *head;
struct kmmio_fault_page *p;
page &= PAGE_MASK;
head = kmmio_page_list(page);
list_for_each_entry_rcu(p, head, list) {
if (p->page == page)
return p;
}
return NULL;
}
static void set_page_present(unsigned long addr, bool present,
unsigned int *pglevel)
{
pteval_t pteval;
pmdval_t pmdval;
unsigned int level;
pmd_t *pmd;
pte_t *pte = lookup_address(addr, &level);
if (!pte) {
pr_err("kmmio: no pte for page 0x%08lx\n", addr);
return;
}
if (pglevel)
*pglevel = level;
switch (level) {
case PG_LEVEL_2M:
pmd = (pmd_t *)pte;
pmdval = pmd_val(*pmd) & ~_PAGE_PRESENT;
if (present)
pmdval |= _PAGE_PRESENT;
set_pmd(pmd, __pmd(pmdval));
break;
case PG_LEVEL_4K:
pteval = pte_val(*pte) & ~_PAGE_PRESENT;
if (present)
pteval |= _PAGE_PRESENT;
set_pte_atomic(pte, __pte(pteval));
break;
default:
pr_err("kmmio: unexpected page level 0x%x.\n", level);
return;
}
__flush_tlb_one(addr);
}
/** Mark the given page as not present. Access to it will trigger a fault. */
static void arm_kmmio_fault_page(unsigned long page, unsigned int *pglevel)
{
set_page_present(page & PAGE_MASK, false, pglevel);
}
/** Mark the given page as present. */
static void disarm_kmmio_fault_page(unsigned long page, unsigned int *pglevel)
{
set_page_present(page & PAGE_MASK, true, pglevel);
}
/*
* This is being called from do_page_fault().
*
* We may be in an interrupt or a critical section. Also prefecthing may
* trigger a page fault. We may be in the middle of process switch.
* We cannot take any locks, because we could be executing especially
* within a kmmio critical section.
*
* Local interrupts are disabled, so preemption cannot happen.
* Do not enable interrupts, do not sleep, and watch out for other CPUs.
*/
/*
* Interrupts are disabled on entry as trap3 is an interrupt gate
* and they remain disabled thorough out this function.
*/
int kmmio_handler(struct pt_regs *regs, unsigned long addr)
{
struct kmmio_context *ctx;
struct kmmio_fault_page *faultpage;
int ret = 0; /* default to fault not handled */
/*
* Preemption is now disabled to prevent process switch during
* single stepping. We can only handle one active kmmio trace
* per cpu, so ensure that we finish it before something else
* gets to run. We also hold the RCU read lock over single
* stepping to avoid looking up the probe and kmmio_fault_page
* again.
*/
preempt_disable();
rcu_read_lock();
faultpage = get_kmmio_fault_page(addr);
if (!faultpage) {
/*
* Either this page fault is not caused by kmmio, or
* another CPU just pulled the kmmio probe from under
* our feet. The latter case should not be possible.
*/
goto no_kmmio;
}
ctx = &get_cpu_var(kmmio_ctx);
if (ctx->active) {
disarm_kmmio_fault_page(faultpage->page, NULL);
if (addr == ctx->addr) {
/*
* On SMP we sometimes get recursive probe hits on the
* same address. Context is already saved, fall out.
*/
pr_debug("kmmio: duplicate probe hit on CPU %d, for "
"address 0x%08lx.\n",
smp_processor_id(), addr);
ret = 1;
goto no_kmmio_ctx;
}
/*
* Prevent overwriting already in-flight context.
* This should not happen, let's hope disarming at least
* prevents a panic.
*/
pr_emerg("kmmio: recursive probe hit on CPU %d, "
"for address 0x%08lx. Ignoring.\n",
smp_processor_id(), addr);
pr_emerg("kmmio: previous hit was at 0x%08lx.\n",
ctx->addr);
goto no_kmmio_ctx;
}
ctx->active++;
ctx->fpage = faultpage;
ctx->probe = get_kmmio_probe(addr);
ctx->saved_flags = (regs->flags & (X86_EFLAGS_TF | X86_EFLAGS_IF));
ctx->addr = addr;
if (ctx->probe && ctx->probe->pre_handler)
ctx->probe->pre_handler(ctx->probe, regs, addr);
/*
* Enable single-stepping and disable interrupts for the faulting
* context. Local interrupts must not get enabled during stepping.
*/
regs->flags |= X86_EFLAGS_TF;
regs->flags &= ~X86_EFLAGS_IF;
/* Now we set present bit in PTE and single step. */
disarm_kmmio_fault_page(ctx->fpage->page, NULL);
/*
* If another cpu accesses the same page while we are stepping,
* the access will not be caught. It will simply succeed and the
* only downside is we lose the event. If this becomes a problem,
* the user should drop to single cpu before tracing.
*/
put_cpu_var(kmmio_ctx);
return 1; /* fault handled */
no_kmmio_ctx:
put_cpu_var(kmmio_ctx);
no_kmmio:
rcu_read_unlock();
preempt_enable_no_resched();
return ret;
}
/*
* Interrupts are disabled on entry as trap1 is an interrupt gate
* and they remain disabled thorough out this function.
* This must always get called as the pair to kmmio_handler().
*/
static int post_kmmio_handler(unsigned long condition, struct pt_regs *regs)
{
int ret = 0;
struct kmmio_context *ctx = &get_cpu_var(kmmio_ctx);
if (!ctx->active) {
pr_debug("kmmio: spurious debug trap on CPU %d.\n",
smp_processor_id());
goto out;
}
if (ctx->probe && ctx->probe->post_handler)
ctx->probe->post_handler(ctx->probe, condition, regs);
arm_kmmio_fault_page(ctx->fpage->page, NULL);
regs->flags &= ~X86_EFLAGS_TF;
regs->flags |= ctx->saved_flags;
/* These were acquired in kmmio_handler(). */
ctx->active--;
BUG_ON(ctx->active);
rcu_read_unlock();
preempt_enable_no_resched();
/*
* if somebody else is singlestepping across a probe point, flags
* will have TF set, in which case, continue the remaining processing
* of do_debug, as if this is not a probe hit.
*/
if (!(regs->flags & X86_EFLAGS_TF))
ret = 1;
out:
put_cpu_var(kmmio_ctx);
return ret;
}
/* You must be holding kmmio_lock. */
static int add_kmmio_fault_page(unsigned long page)
{
struct kmmio_fault_page *f;
page &= PAGE_MASK;
f = get_kmmio_fault_page(page);
if (f) {
if (!f->count)
arm_kmmio_fault_page(f->page, NULL);
f->count++;
return 0;
}
f = kmalloc(sizeof(*f), GFP_ATOMIC);
if (!f)
return -1;
f->count = 1;
f->page = page;
list_add_rcu(&f->list, kmmio_page_list(f->page));
arm_kmmio_fault_page(f->page, NULL);
return 0;
}
/* You must be holding kmmio_lock. */
static void release_kmmio_fault_page(unsigned long page,
struct kmmio_fault_page **release_list)
{
struct kmmio_fault_page *f;
page &= PAGE_MASK;
f = get_kmmio_fault_page(page);
if (!f)
return;
f->count--;
BUG_ON(f->count < 0);
if (!f->count) {
disarm_kmmio_fault_page(f->page, NULL);
f->release_next = *release_list;
*release_list = f;
}
}
/*
* With page-unaligned ioremaps, one or two armed pages may contain
* addresses from outside the intended mapping. Events for these addresses
* are currently silently dropped. The events may result only from programming
* mistakes by accessing addresses before the beginning or past the end of a
* mapping.
*/
int register_kmmio_probe(struct kmmio_probe *p)
{
unsigned long flags;
int ret = 0;
unsigned long size = 0;
const unsigned long size_lim = p->len + (p->addr & ~PAGE_MASK);
spin_lock_irqsave(&kmmio_lock, flags);
if (get_kmmio_probe(p->addr)) {
ret = -EEXIST;
goto out;
}
kmmio_count++;
list_add_rcu(&p->list, &kmmio_probes);
while (size < size_lim) {
if (add_kmmio_fault_page(p->addr + size))
pr_err("kmmio: Unable to set page fault.\n");
size += PAGE_SIZE;
}
out:
spin_unlock_irqrestore(&kmmio_lock, flags);
/*
* XXX: What should I do here?
* Here was a call to global_flush_tlb(), but it does not exist
* anymore. It seems it's not needed after all.
*/
return ret;
}
EXPORT_SYMBOL(register_kmmio_probe);
static void rcu_free_kmmio_fault_pages(struct rcu_head *head)
{
struct kmmio_delayed_release *dr = container_of(
head,
struct kmmio_delayed_release,
rcu);
struct kmmio_fault_page *p = dr->release_list;
while (p) {
struct kmmio_fault_page *next = p->release_next;
BUG_ON(p->count);
kfree(p);
p = next;
}
kfree(dr);
}
static void remove_kmmio_fault_pages(struct rcu_head *head)
{
struct kmmio_delayed_release *dr = container_of(
head,
struct kmmio_delayed_release,
rcu);
struct kmmio_fault_page *p = dr->release_list;
struct kmmio_fault_page **prevp = &dr->release_list;
unsigned long flags;
spin_lock_irqsave(&kmmio_lock, flags);
while (p) {
if (!p->count)
list_del_rcu(&p->list);
else
*prevp = p->release_next;
prevp = &p->release_next;
p = p->release_next;
}
spin_unlock_irqrestore(&kmmio_lock, flags);
/* This is the real RCU destroy call. */
call_rcu(&dr->rcu, rcu_free_kmmio_fault_pages);
}
/*
* Remove a kmmio probe. You have to synchronize_rcu() before you can be
* sure that the callbacks will not be called anymore. Only after that
* you may actually release your struct kmmio_probe.
*
* Unregistering a kmmio fault page has three steps:
* 1. release_kmmio_fault_page()
* Disarm the page, wait a grace period to let all faults finish.
* 2. remove_kmmio_fault_pages()
* Remove the pages from kmmio_page_table.
* 3. rcu_free_kmmio_fault_pages()
* Actally free the kmmio_fault_page structs as with RCU.
*/
void unregister_kmmio_probe(struct kmmio_probe *p)
{
unsigned long flags;
unsigned long size = 0;
const unsigned long size_lim = p->len + (p->addr & ~PAGE_MASK);
struct kmmio_fault_page *release_list = NULL;
struct kmmio_delayed_release *drelease;
spin_lock_irqsave(&kmmio_lock, flags);
while (size < size_lim) {
release_kmmio_fault_page(p->addr + size, &release_list);
size += PAGE_SIZE;
}
list_del_rcu(&p->list);
kmmio_count--;
spin_unlock_irqrestore(&kmmio_lock, flags);
drelease = kmalloc(sizeof(*drelease), GFP_ATOMIC);
if (!drelease) {
pr_crit("kmmio: leaking kmmio_fault_page objects.\n");
return;
}
drelease->release_list = release_list;
/*
* This is not really RCU here. We have just disarmed a set of
* pages so that they cannot trigger page faults anymore. However,
* we cannot remove the pages from kmmio_page_table,
* because a probe hit might be in flight on another CPU. The
* pages are collected into a list, and they will be removed from
* kmmio_page_table when it is certain that no probe hit related to
* these pages can be in flight. RCU grace period sounds like a
* good choice.
*
* If we removed the pages too early, kmmio page fault handler might
* not find the respective kmmio_fault_page and determine it's not
* a kmmio fault, when it actually is. This would lead to madness.
*/
call_rcu(&drelease->rcu, remove_kmmio_fault_pages);
}
EXPORT_SYMBOL(unregister_kmmio_probe);
static int kmmio_die_notifier(struct notifier_block *nb, unsigned long val,
void *args)
{
struct die_args *arg = args;
if (val == DIE_DEBUG && (arg->err & DR_STEP))
if (post_kmmio_handler(arg->err, arg->regs) == 1)
return NOTIFY_STOP;
return NOTIFY_DONE;
}
static struct notifier_block nb_die = {
.notifier_call = kmmio_die_notifier
};
static int __init init_kmmio(void)
{
int i;
for (i = 0; i < KMMIO_PAGE_TABLE_SIZE; i++)
INIT_LIST_HEAD(&kmmio_page_table[i]);
return register_die_notifier(&nb_die);
}
fs_initcall(init_kmmio); /* should be before device_initcall() */

515
arch/x86/mm/mmio-mod.c Normal file
View File

@ -0,0 +1,515 @@
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* Copyright (C) IBM Corporation, 2005
* Jeff Muizelaar, 2006, 2007
* Pekka Paalanen, 2008 <pq@iki.fi>
*
* Derived from the read-mod example from relay-examples by Tom Zanussi.
*/
#define DEBUG 1
#include <linux/module.h>
#include <linux/debugfs.h>
#include <linux/uaccess.h>
#include <linux/io.h>
#include <linux/version.h>
#include <linux/kallsyms.h>
#include <asm/pgtable.h>
#include <linux/mmiotrace.h>
#include <asm/e820.h> /* for ISA_START_ADDRESS */
#include <asm/atomic.h>
#include <linux/percpu.h>
#include <linux/cpu.h>
#include "pf_in.h"
#define NAME "mmiotrace: "
struct trap_reason {
unsigned long addr;
unsigned long ip;
enum reason_type type;
int active_traces;
};
struct remap_trace {
struct list_head list;
struct kmmio_probe probe;
resource_size_t phys;
unsigned long id;
};
/* Accessed per-cpu. */
static DEFINE_PER_CPU(struct trap_reason, pf_reason);
static DEFINE_PER_CPU(struct mmiotrace_rw, cpu_trace);
#if 0 /* XXX: no way gather this info anymore */
/* Access to this is not per-cpu. */
static DEFINE_PER_CPU(atomic_t, dropped);
#endif
static struct dentry *marker_file;
static DEFINE_MUTEX(mmiotrace_mutex);
static DEFINE_SPINLOCK(trace_lock);
static atomic_t mmiotrace_enabled;
static LIST_HEAD(trace_list); /* struct remap_trace */
/*
* Locking in this file:
* - mmiotrace_mutex enforces enable/disable_mmiotrace() critical sections.
* - mmiotrace_enabled may be modified only when holding mmiotrace_mutex
* and trace_lock.
* - Routines depending on is_enabled() must take trace_lock.
* - trace_list users must hold trace_lock.
* - is_enabled() guarantees that mmio_trace_record is allowed.
* - pre/post callbacks assume the effect of is_enabled() being true.
*/
/* module parameters */
static unsigned long filter_offset;
static int nommiotrace;
static int trace_pc;
module_param(filter_offset, ulong, 0);
module_param(nommiotrace, bool, 0);
module_param(trace_pc, bool, 0);
MODULE_PARM_DESC(filter_offset, "Start address of traced mappings.");
MODULE_PARM_DESC(nommiotrace, "Disable actual MMIO tracing.");
MODULE_PARM_DESC(trace_pc, "Record address of faulting instructions.");
static bool is_enabled(void)
{
return atomic_read(&mmiotrace_enabled);
}
#if 0 /* XXX: needs rewrite */
/*
* Write callback for the debugfs entry:
* Read a marker and write it to the mmio trace log
*/
static ssize_t write_marker(struct file *file, const char __user *buffer,
size_t count, loff_t *ppos)
{
char *event = NULL;
struct mm_io_header *headp;
ssize_t len = (count > 65535) ? 65535 : count;
event = kzalloc(sizeof(*headp) + len, GFP_KERNEL);
if (!event)
return -ENOMEM;
headp = (struct mm_io_header *)event;
headp->type = MMIO_MAGIC | (MMIO_MARKER << MMIO_OPCODE_SHIFT);
headp->data_len = len;
if (copy_from_user(event + sizeof(*headp), buffer, len)) {
kfree(event);
return -EFAULT;
}
spin_lock_irq(&trace_lock);
#if 0 /* XXX: convert this to use tracing */
if (is_enabled())
relay_write(chan, event, sizeof(*headp) + len);
else
#endif
len = -EINVAL;
spin_unlock_irq(&trace_lock);
kfree(event);
return len;
}
#endif
static void print_pte(unsigned long address)
{
unsigned int level;
pte_t *pte = lookup_address(address, &level);
if (!pte) {
pr_err(NAME "Error in %s: no pte for page 0x%08lx\n",
__func__, address);
return;
}
if (level == PG_LEVEL_2M) {
pr_emerg(NAME "4MB pages are not currently supported: "
"0x%08lx\n", address);
BUG();
}
pr_info(NAME "pte for 0x%lx: 0x%llx 0x%llx\n", address,
(unsigned long long)pte_val(*pte),
(unsigned long long)pte_val(*pte) & _PAGE_PRESENT);
}
/*
* For some reason the pre/post pairs have been called in an
* unmatched order. Report and die.
*/
static void die_kmmio_nesting_error(struct pt_regs *regs, unsigned long addr)
{
const struct trap_reason *my_reason = &get_cpu_var(pf_reason);
pr_emerg(NAME "unexpected fault for address: 0x%08lx, "
"last fault for address: 0x%08lx\n",
addr, my_reason->addr);
print_pte(addr);
print_symbol(KERN_EMERG "faulting IP is at %s\n", regs->ip);
print_symbol(KERN_EMERG "last faulting IP was at %s\n", my_reason->ip);
#ifdef __i386__
pr_emerg("eax: %08lx ebx: %08lx ecx: %08lx edx: %08lx\n",
regs->ax, regs->bx, regs->cx, regs->dx);
pr_emerg("esi: %08lx edi: %08lx ebp: %08lx esp: %08lx\n",
regs->si, regs->di, regs->bp, regs->sp);
#else
pr_emerg("rax: %016lx rcx: %016lx rdx: %016lx\n",
regs->ax, regs->cx, regs->dx);
pr_emerg("rsi: %016lx rdi: %016lx rbp: %016lx rsp: %016lx\n",
regs->si, regs->di, regs->bp, regs->sp);
#endif
put_cpu_var(pf_reason);
BUG();
}
static void pre(struct kmmio_probe *p, struct pt_regs *regs,
unsigned long addr)
{
struct trap_reason *my_reason = &get_cpu_var(pf_reason);
struct mmiotrace_rw *my_trace = &get_cpu_var(cpu_trace);
const unsigned long instptr = instruction_pointer(regs);
const enum reason_type type = get_ins_type(instptr);
struct remap_trace *trace = p->private;
/* it doesn't make sense to have more than one active trace per cpu */
if (my_reason->active_traces)
die_kmmio_nesting_error(regs, addr);
else
my_reason->active_traces++;
my_reason->type = type;
my_reason->addr = addr;
my_reason->ip = instptr;
my_trace->phys = addr - trace->probe.addr + trace->phys;
my_trace->map_id = trace->id;
/*
* Only record the program counter when requested.
* It may taint clean-room reverse engineering.
*/
if (trace_pc)
my_trace->pc = instptr;
else
my_trace->pc = 0;
/*
* XXX: the timestamp recorded will be *after* the tracing has been
* done, not at the time we hit the instruction. SMP implications
* on event ordering?
*/
switch (type) {
case REG_READ:
my_trace->opcode = MMIO_READ;
my_trace->width = get_ins_mem_width(instptr);
break;
case REG_WRITE:
my_trace->opcode = MMIO_WRITE;
my_trace->width = get_ins_mem_width(instptr);
my_trace->value = get_ins_reg_val(instptr, regs);
break;
case IMM_WRITE:
my_trace->opcode = MMIO_WRITE;
my_trace->width = get_ins_mem_width(instptr);
my_trace->value = get_ins_imm_val(instptr);
break;
default:
{
unsigned char *ip = (unsigned char *)instptr;
my_trace->opcode = MMIO_UNKNOWN_OP;
my_trace->width = 0;
my_trace->value = (*ip) << 16 | *(ip + 1) << 8 |
*(ip + 2);
}
}
put_cpu_var(cpu_trace);
put_cpu_var(pf_reason);
}
static void post(struct kmmio_probe *p, unsigned long condition,
struct pt_regs *regs)
{
struct trap_reason *my_reason = &get_cpu_var(pf_reason);
struct mmiotrace_rw *my_trace = &get_cpu_var(cpu_trace);
/* this should always return the active_trace count to 0 */
my_reason->active_traces--;
if (my_reason->active_traces) {
pr_emerg(NAME "unexpected post handler");
BUG();
}
switch (my_reason->type) {
case REG_READ:
my_trace->value = get_ins_reg_val(my_reason->ip, regs);
break;
default:
break;
}
mmio_trace_rw(my_trace);
put_cpu_var(cpu_trace);
put_cpu_var(pf_reason);
}
static void ioremap_trace_core(resource_size_t offset, unsigned long size,
void __iomem *addr)
{
static atomic_t next_id;
struct remap_trace *trace = kmalloc(sizeof(*trace), GFP_KERNEL);
/* These are page-unaligned. */
struct mmiotrace_map map = {
.phys = offset,
.virt = (unsigned long)addr,
.len = size,
.opcode = MMIO_PROBE
};
if (!trace) {
pr_err(NAME "kmalloc failed in ioremap\n");
return;
}
*trace = (struct remap_trace) {
.probe = {
.addr = (unsigned long)addr,
.len = size,
.pre_handler = pre,
.post_handler = post,
.private = trace
},
.phys = offset,
.id = atomic_inc_return(&next_id)
};
map.map_id = trace->id;
spin_lock_irq(&trace_lock);
if (!is_enabled())
goto not_enabled;
mmio_trace_mapping(&map);
list_add_tail(&trace->list, &trace_list);
if (!nommiotrace)
register_kmmio_probe(&trace->probe);
not_enabled:
spin_unlock_irq(&trace_lock);
}
void mmiotrace_ioremap(resource_size_t offset, unsigned long size,
void __iomem *addr)
{
if (!is_enabled()) /* recheck and proper locking in *_core() */
return;
pr_debug(NAME "ioremap_*(0x%llx, 0x%lx) = %p\n",
(unsigned long long)offset, size, addr);
if ((filter_offset) && (offset != filter_offset))
return;
ioremap_trace_core(offset, size, addr);
}
static void iounmap_trace_core(volatile void __iomem *addr)
{
struct mmiotrace_map map = {
.phys = 0,
.virt = (unsigned long)addr,
.len = 0,
.opcode = MMIO_UNPROBE
};
struct remap_trace *trace;
struct remap_trace *tmp;
struct remap_trace *found_trace = NULL;
pr_debug(NAME "Unmapping %p.\n", addr);
spin_lock_irq(&trace_lock);
if (!is_enabled())
goto not_enabled;
list_for_each_entry_safe(trace, tmp, &trace_list, list) {
if ((unsigned long)addr == trace->probe.addr) {
if (!nommiotrace)
unregister_kmmio_probe(&trace->probe);
list_del(&trace->list);
found_trace = trace;
break;
}
}
map.map_id = (found_trace) ? found_trace->id : -1;
mmio_trace_mapping(&map);
not_enabled:
spin_unlock_irq(&trace_lock);
if (found_trace) {
synchronize_rcu(); /* unregister_kmmio_probe() requirement */
kfree(found_trace);
}
}
void mmiotrace_iounmap(volatile void __iomem *addr)
{
might_sleep();
if (is_enabled()) /* recheck and proper locking in *_core() */
iounmap_trace_core(addr);
}
static void clear_trace_list(void)
{
struct remap_trace *trace;
struct remap_trace *tmp;
/*
* No locking required, because the caller ensures we are in a
* critical section via mutex, and is_enabled() is false,
* i.e. nothing can traverse or modify this list.
* Caller also ensures is_enabled() cannot change.
*/
list_for_each_entry(trace, &trace_list, list) {
pr_notice(NAME "purging non-iounmapped "
"trace @0x%08lx, size 0x%lx.\n",
trace->probe.addr, trace->probe.len);
if (!nommiotrace)
unregister_kmmio_probe(&trace->probe);
}
synchronize_rcu(); /* unregister_kmmio_probe() requirement */
list_for_each_entry_safe(trace, tmp, &trace_list, list) {
list_del(&trace->list);
kfree(trace);
}
}
#ifdef CONFIG_HOTPLUG_CPU
static cpumask_t downed_cpus;
static void enter_uniprocessor(void)
{
int cpu;
int err;
get_online_cpus();
downed_cpus = cpu_online_map;
cpu_clear(first_cpu(cpu_online_map), downed_cpus);
if (num_online_cpus() > 1)
pr_notice(NAME "Disabling non-boot CPUs...\n");
put_online_cpus();
for_each_cpu_mask(cpu, downed_cpus) {
err = cpu_down(cpu);
if (!err)
pr_info(NAME "CPU%d is down.\n", cpu);
else
pr_err(NAME "Error taking CPU%d down: %d\n", cpu, err);
}
if (num_online_cpus() > 1)
pr_warning(NAME "multiple CPUs still online, "
"may miss events.\n");
}
static void leave_uniprocessor(void)
{
int cpu;
int err;
if (cpus_weight(downed_cpus) == 0)
return;
pr_notice(NAME "Re-enabling CPUs...\n");
for_each_cpu_mask(cpu, downed_cpus) {
err = cpu_up(cpu);
if (!err)
pr_info(NAME "enabled CPU%d.\n", cpu);
else
pr_err(NAME "cannot re-enable CPU%d: %d\n", cpu, err);
}
}
#else /* !CONFIG_HOTPLUG_CPU */
static void enter_uniprocessor(void)
{
if (num_online_cpus() > 1)
pr_warning(NAME "multiple CPUs are online, may miss events. "
"Suggest booting with maxcpus=1 kernel argument.\n");
}
static void leave_uniprocessor(void)
{
}
#endif
#if 0 /* XXX: out of order */
static struct file_operations fops_marker = {
.owner = THIS_MODULE,
.write = write_marker
};
#endif
void enable_mmiotrace(void)
{
mutex_lock(&mmiotrace_mutex);
if (is_enabled())
goto out;
#if 0 /* XXX: tracing does not support text entries */
marker_file = debugfs_create_file("marker", 0660, dir, NULL,
&fops_marker);
if (!marker_file)
pr_err(NAME "marker file creation failed.\n");
#endif
if (nommiotrace)
pr_info(NAME "MMIO tracing disabled.\n");
enter_uniprocessor();
spin_lock_irq(&trace_lock);
atomic_inc(&mmiotrace_enabled);
spin_unlock_irq(&trace_lock);
pr_info(NAME "enabled.\n");
out:
mutex_unlock(&mmiotrace_mutex);
}
void disable_mmiotrace(void)
{
mutex_lock(&mmiotrace_mutex);
if (!is_enabled())
goto out;
spin_lock_irq(&trace_lock);
atomic_dec(&mmiotrace_enabled);
BUG_ON(is_enabled());
spin_unlock_irq(&trace_lock);
clear_trace_list(); /* guarantees: no more kmmio callbacks */
leave_uniprocessor();
if (marker_file) {
debugfs_remove(marker_file);
marker_file = NULL;
}
pr_info(NAME "disabled.\n");
out:
mutex_unlock(&mmiotrace_mutex);
}

1
arch/x86/mm/pageattr.c
View File

@ -227,6 +227,7 @@ pte_t *lookup_address(unsigned long address, unsigned int *level)
return pte_offset_kernel(pmd, address);
}
EXPORT_SYMBOL_GPL(lookup_address);
/*
* Set the new pmd in all the pgds we know about:

489
arch/x86/mm/pf_in.c Normal file
View File

@ -0,0 +1,489 @@
/*
* Fault Injection Test harness (FI)
* Copyright (C) Intel Crop.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
* USA.
*
*/
/* Id: pf_in.c,v 1.1.1.1 2002/11/12 05:56:32 brlock Exp
* Copyright by Intel Crop., 2002
* Louis Zhuang (louis.zhuang@intel.com)
*
* Bjorn Steinbrink (B.Steinbrink@gmx.de), 2007
*/
#include <linux/module.h>
#include <linux/ptrace.h> /* struct pt_regs */
#include "pf_in.h"
#ifdef __i386__
/* IA32 Manual 3, 2-1 */
static unsigned char prefix_codes[] = {
0xF0, 0xF2, 0xF3, 0x2E, 0x36, 0x3E, 0x26, 0x64,
0x65, 0x2E, 0x3E, 0x66, 0x67
};
/* IA32 Manual 3, 3-432*/
static unsigned int reg_rop[] = {
0x8A, 0x8B, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F
};
static unsigned int reg_wop[] = { 0x88, 0x89 };
static unsigned int imm_wop[] = { 0xC6, 0xC7 };
/* IA32 Manual 3, 3-432*/
static unsigned int rw8[] = { 0x88, 0x8A, 0xC6 };
static unsigned int rw32[] = {
0x89, 0x8B, 0xC7, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F
};
static unsigned int mw8[] = { 0x88, 0x8A, 0xC6, 0xB60F, 0xBE0F };
static unsigned int mw16[] = { 0xB70F, 0xBF0F };
static unsigned int mw32[] = { 0x89, 0x8B, 0xC7 };
static unsigned int mw64[] = {};
#else /* not __i386__ */
static unsigned char prefix_codes[] = {
0x66, 0x67, 0x2E, 0x3E, 0x26, 0x64, 0x65, 0x36,
0xF0, 0xF3, 0xF2,
/* REX Prefixes */
0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f
};
/* AMD64 Manual 3, Appendix A*/
static unsigned int reg_rop[] = {
0x8A, 0x8B, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F
};
static unsigned int reg_wop[] = { 0x88, 0x89 };
static unsigned int imm_wop[] = { 0xC6, 0xC7 };
static unsigned int rw8[] = { 0xC6, 0x88, 0x8A };
static unsigned int rw32[] = {
0xC7, 0x89, 0x8B, 0xB60F, 0xB70F, 0xBE0F, 0xBF0F
};
/* 8 bit only */
static unsigned int mw8[] = { 0xC6, 0x88, 0x8A, 0xB60F, 0xBE0F };
/* 16 bit only */
static unsigned int mw16[] = { 0xB70F, 0xBF0F };
/* 16 or 32 bit */
static unsigned int mw32[] = { 0xC7 };
/* 16, 32 or 64 bit */
static unsigned int mw64[] = { 0x89, 0x8B };
#endif /* not __i386__ */
static int skip_prefix(unsigned char *addr, int *shorted, int *enlarged,
int *rexr)
{
int i;
unsigned char *p = addr;
*shorted = 0;
*enlarged = 0;
*rexr = 0;
restart:
for (i = 0; i < ARRAY_SIZE(prefix_codes); i++) {
if (*p == prefix_codes[i]) {
if (*p == 0x66)
*shorted = 1;
#ifdef __amd64__
if ((*p & 0xf8) == 0x48)
*enlarged = 1;
if ((*p & 0xf4) == 0x44)
*rexr = 1;
#endif
p++;
goto restart;
}
}
return (p - addr);
}
static int get_opcode(unsigned char *addr, unsigned int *opcode)
{
int len;
if (*addr == 0x0F) {
/* 0x0F is extension instruction */
*opcode = *(unsigned short *)addr;
len = 2;
} else {
*opcode = *addr;
len = 1;
}
return len;
}
#define CHECK_OP_TYPE(opcode, array, type) \
for (i = 0; i < ARRAY_SIZE(array); i++) { \
if (array[i] == opcode) { \
rv = type; \
goto exit; \
} \
}
enum reason_type get_ins_type(unsigned long ins_addr)
{
unsigned int opcode;
unsigned char *p;
int shorted, enlarged, rexr;
int i;
enum reason_type rv = OTHERS;
p = (unsigned char *)ins_addr;
p += skip_prefix(p, &shorted, &enlarged, &rexr);
p += get_opcode(p, &opcode);
CHECK_OP_TYPE(opcode, reg_rop, REG_READ);
CHECK_OP_TYPE(opcode, reg_wop, REG_WRITE);
CHECK_OP_TYPE(opcode, imm_wop, IMM_WRITE);
exit:
return rv;
}
#undef CHECK_OP_TYPE
static unsigned int get_ins_reg_width(unsigned long ins_addr)
{
unsigned int opcode;
unsigned char *p;
int i, shorted, enlarged, rexr;
p = (unsigned char *)ins_addr;
p += skip_prefix(p, &shorted, &enlarged, &rexr);
p += get_opcode(p, &opcode);
for (i = 0; i < ARRAY_SIZE(rw8); i++)
if (rw8[i] == opcode)
return 1;
for (i = 0; i < ARRAY_SIZE(rw32); i++)
if (rw32[i] == opcode)
return (shorted ? 2 : (enlarged ? 8 : 4));
printk(KERN_ERR "mmiotrace: Unknown opcode 0x%02x\n", opcode);
return 0;
}
unsigned int get_ins_mem_width(unsigned long ins_addr)
{
unsigned int opcode;
unsigned char *p;
int i, shorted, enlarged, rexr;
p = (unsigned char *)ins_addr;
p += skip_prefix(p, &shorted, &enlarged, &rexr);
p += get_opcode(p, &opcode);
for (i = 0; i < ARRAY_SIZE(mw8); i++)
if (mw8[i] == opcode)
return 1;
for (i = 0; i < ARRAY_SIZE(mw16); i++)
if (mw16[i] == opcode)
return 2;
for (i = 0; i < ARRAY_SIZE(mw32); i++)
if (mw32[i] == opcode)
return shorted ? 2 : 4;
for (i = 0; i < ARRAY_SIZE(mw64); i++)
if (mw64[i] == opcode)
return shorted ? 2 : (enlarged ? 8 : 4);
printk(KERN_ERR "mmiotrace: Unknown opcode 0x%02x\n", opcode);
return 0;
}
/*
* Define register ident in mod/rm byte.
* Note: these are NOT the same as in ptrace-abi.h.
*/
enum {
arg_AL = 0,
arg_CL = 1,
arg_DL = 2,
arg_BL = 3,
arg_AH = 4,
arg_CH = 5,
arg_DH = 6,
arg_BH = 7,
arg_AX = 0,
arg_CX = 1,
arg_DX = 2,
arg_BX = 3,
arg_SP = 4,
arg_BP = 5,
arg_SI = 6,
arg_DI = 7,
#ifdef __amd64__
arg_R8 = 8,
arg_R9 = 9,
arg_R10 = 10,
arg_R11 = 11,
arg_R12 = 12,
arg_R13 = 13,
arg_R14 = 14,
arg_R15 = 15
#endif
};
static unsigned char *get_reg_w8(int no, struct pt_regs *regs)
{
unsigned char *rv = NULL;
switch (no) {
case arg_AL:
rv = (unsigned char *)&regs->ax;
break;
case arg_BL:
rv = (unsigned char *)&regs->bx;
break;
case arg_CL:
rv = (unsigned char *)&regs->cx;
break;
case arg_DL:
rv = (unsigned char *)&regs->dx;
break;
case arg_AH:
rv = 1 + (unsigned char *)&regs->ax;
break;
case arg_BH:
rv = 1 + (unsigned char *)&regs->bx;
break;
case arg_CH:
rv = 1 + (unsigned char *)&regs->cx;
break;
case arg_DH:
rv = 1 + (unsigned char *)&regs->dx;
break;
#ifdef __amd64__
case arg_R8:
rv = (unsigned char *)&regs->r8;
break;
case arg_R9:
rv = (unsigned char *)&regs->r9;
break;
case arg_R10:
rv = (unsigned char *)&regs->r10;
break;
case arg_R11:
rv = (unsigned char *)&regs->r11;
break;
case arg_R12:
rv = (unsigned char *)&regs->r12;
break;
case arg_R13:
rv = (unsigned char *)&regs->r13;
break;
case arg_R14:
rv = (unsigned char *)&regs->r14;
break;
case arg_R15:
rv = (unsigned char *)&regs->r15;
break;
#endif
default:
printk(KERN_ERR "mmiotrace: Error reg no# %d\n", no);
break;
}
return rv;
}
static unsigned long *get_reg_w32(int no, struct pt_regs *regs)
{
unsigned long *rv = NULL;
switch (no) {
case arg_AX:
rv = &regs->ax;
break;
case arg_BX:
rv = &regs->bx;
break;
case arg_CX:
rv = &regs->cx;
break;
case arg_DX:
rv = &regs->dx;
break;
case arg_SP:
rv = &regs->sp;
break;
case arg_BP:
rv = &regs->bp;
break;
case arg_SI:
rv = &regs->si;
break;
case arg_DI:
rv = &regs->di;
break;
#ifdef __amd64__
case arg_R8:
rv = &regs->r8;
break;
case arg_R9:
rv = &regs->r9;
break;
case arg_R10:
rv = &regs->r10;
break;
case arg_R11:
rv = &regs->r11;
break;
case arg_R12:
rv = &regs->r12;
break;
case arg_R13:
rv = &regs->r13;
break;
case arg_R14:
rv = &regs->r14;
break;
case arg_R15:
rv = &regs->r15;
break;
#endif
default:
printk(KERN_ERR "mmiotrace: Error reg no# %d\n", no);
}
return rv;
}
unsigned long get_ins_reg_val(unsigned long ins_addr, struct pt_regs *regs)
{
unsigned int opcode;
unsigned char mod_rm;
int reg;
unsigned char *p;
int i, shorted, enlarged, rexr;
unsigned long rv;
p = (unsigned char *)ins_addr;
p += skip_prefix(p, &shorted, &enlarged, &rexr);
p += get_opcode(p, &opcode);
for (i = 0; i < ARRAY_SIZE(reg_rop); i++)
if (reg_rop[i] == opcode) {
rv = REG_READ;
goto do_work;
}
for (i = 0; i < ARRAY_SIZE(reg_wop); i++)
if (reg_wop[i] == opcode) {
rv = REG_WRITE;
goto do_work;
}
printk(KERN_ERR "mmiotrace: Not a register instruction, opcode "
"0x%02x\n", opcode);
goto err;
do_work:
mod_rm = *p;
reg = ((mod_rm >> 3) & 0x7) | (rexr << 3);
switch (get_ins_reg_width(ins_addr)) {
case 1:
return *get_reg_w8(reg, regs);
case 2:
return *(unsigned short *)get_reg_w32(reg, regs);
case 4:
return *(unsigned int *)get_reg_w32(reg, regs);
#ifdef __amd64__
case 8:
return *(unsigned long *)get_reg_w32(reg, regs);
#endif
default:
printk(KERN_ERR "mmiotrace: Error width# %d\n", reg);
}
err:
return 0;
}
unsigned long get_ins_imm_val(unsigned long ins_addr)
{
unsigned int opcode;
unsigned char mod_rm;
unsigned char mod;
unsigned char *p;
int i, shorted, enlarged, rexr;
unsigned long rv;
p = (unsigned char *)ins_addr;
p += skip_prefix(p, &shorted, &enlarged, &rexr);
p += get_opcode(p, &opcode);
for (i = 0; i < ARRAY_SIZE(imm_wop); i++)
if (imm_wop[i] == opcode) {
rv = IMM_WRITE;
goto do_work;
}
printk(KERN_ERR "mmiotrace: Not an immediate instruction, opcode "
"0x%02x\n", opcode);
goto err;
do_work:
mod_rm = *p;
mod = mod_rm >> 6;
p++;
switch (mod) {
case 0:
/* if r/m is 5 we have a 32 disp (IA32 Manual 3, Table 2-2) */
/* AMD64: XXX Check for address size prefix? */
if ((mod_rm & 0x7) == 0x5)
p += 4;
break;
case 1:
p += 1;
break;
case 2:
p += 4;
break;
case 3:
default:
printk(KERN_ERR "mmiotrace: not a memory access instruction "
"at 0x%lx, rm_mod=0x%02x\n",
ins_addr, mod_rm);
}
switch (get_ins_reg_width(ins_addr)) {
case 1:
return *(unsigned char *)p;
case 2:
return *(unsigned short *)p;
case 4:
return *(unsigned int *)p;
#ifdef __amd64__
case 8:
return *(unsigned long *)p;
#endif
default:
printk(KERN_ERR "mmiotrace: Error: width.\n");
}
err:
return 0;
}

39
arch/x86/mm/pf_in.h Normal file
View File

@ -0,0 +1,39 @@
/*
* Fault Injection Test harness (FI)
* Copyright (C) Intel Crop.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
* USA.
*
*/
#ifndef __PF_H_
#define __PF_H_
enum reason_type {
NOT_ME, /* page fault is not in regions */
NOTHING, /* access others point in regions */
REG_READ, /* read from addr to reg */
REG_WRITE, /* write from reg to addr */
IMM_WRITE, /* write from imm to addr */
OTHERS /* Other instructions can not intercept */
};
enum reason_type get_ins_type(unsigned long ins_addr);
unsigned int get_ins_mem_width(unsigned long ins_addr);
unsigned long get_ins_reg_val(unsigned long ins_addr, struct pt_regs *regs);
unsigned long get_ins_imm_val(unsigned long ins_addr);
#endif /* __PF_H_ */

71
arch/x86/mm/testmmiotrace.c Normal file
View File

@ -0,0 +1,71 @@
/*
* Written by Pekka Paalanen, 2008 <pq@iki.fi>
*/
#include <linux/module.h>
#include <linux/io.h>
#define MODULE_NAME "testmmiotrace"
static unsigned long mmio_address;
module_param(mmio_address, ulong, 0);
MODULE_PARM_DESC(mmio_address, "Start address of the mapping of 16 kB.");
static void do_write_test(void __iomem *p)
{
unsigned int i;
for (i = 0; i < 256; i++)
iowrite8(i, p + i);
for (i = 1024; i < (5 * 1024); i += 2)
iowrite16(i * 12 + 7, p + i);
for (i = (5 * 1024); i < (16 * 1024); i += 4)
iowrite32(i * 212371 + 13, p + i);
}
static void do_read_test(void __iomem *p)
{
unsigned int i;
for (i = 0; i < 256; i++)
ioread8(p + i);
for (i = 1024; i < (5 * 1024); i += 2)
ioread16(p + i);
for (i = (5 * 1024); i < (16 * 1024); i += 4)
ioread32(p + i);
}
static void do_test(void)
{
void __iomem *p = ioremap_nocache(mmio_address, 0x4000);
if (!p) {
pr_err(MODULE_NAME ": could not ioremap, aborting.\n");
return;
}
do_write_test(p);
do_read_test(p);
iounmap(p);
}
static int __init init(void)
{
if (mmio_address == 0) {
pr_err(MODULE_NAME ": you have to use the module argument "
"mmio_address.\n");
pr_err(MODULE_NAME ": DO NOT LOAD THIS MODULE UNLESS"
" YOU REALLY KNOW WHAT YOU ARE DOING!\n");
return -ENXIO;
}
pr_warning(MODULE_NAME ": WARNING: mapping 16 kB @ 0x%08lx "
"in PCI address space, and writing "
"rubbish in there.\n", mmio_address);
do_test();
return 0;
}
static void __exit cleanup(void)
{
pr_debug(MODULE_NAME ": unloaded.\n");
}
module_init(init);
module_exit(cleanup);
MODULE_LICENSE("GPL");

9
include/asm-x86/kdebug.h
View File

@ -35,13 +35,4 @@ extern void show_regs(struct pt_regs *regs);
extern unsigned long oops_begin(void);
extern void oops_end(unsigned long, struct pt_regs *, int signr);
struct pf_handler {
struct hlist_node hlist;
int (*handler)(struct pt_regs *regs, unsigned long error_code,
unsigned long address);
};
extern void register_page_fault_handler(struct pf_handler *new_pfh);
extern void unregister_page_fault_handler(struct pf_handler *old_pfh);
#endif

85
include/linux/mmiotrace.h Normal file
View File

@ -0,0 +1,85 @@
#ifndef MMIOTRACE_H
#define MMIOTRACE_H
#include <linux/types.h>
#include <linux/list.h>
struct kmmio_probe;
struct pt_regs;
typedef void (*kmmio_pre_handler_t)(struct kmmio_probe *,
struct pt_regs *, unsigned long addr);
typedef void (*kmmio_post_handler_t)(struct kmmio_probe *,
unsigned long condition, struct pt_regs *);
struct kmmio_probe {
struct list_head list; /* kmmio internal list */
unsigned long addr; /* start location of the probe point */
unsigned long len; /* length of the probe region */
kmmio_pre_handler_t pre_handler; /* Called before addr is executed. */
kmmio_post_handler_t post_handler; /* Called after addr is executed */
void *private;
};
/* kmmio is active by some kmmio_probes? */
static inline int is_kmmio_active(void)
{
extern unsigned int kmmio_count;
return kmmio_count;
}
extern int register_kmmio_probe(struct kmmio_probe *p);
extern void unregister_kmmio_probe(struct kmmio_probe *p);
/* Called from page fault handler. */
extern int kmmio_handler(struct pt_regs *regs, unsigned long addr);
/* Called from ioremap.c */
#ifdef CONFIG_MMIOTRACE
extern void mmiotrace_ioremap(resource_size_t offset, unsigned long size,
void __iomem *addr);
extern void mmiotrace_iounmap(volatile void __iomem *addr);
#else
static inline void mmiotrace_ioremap(resource_size_t offset,
unsigned long size, void __iomem *addr)
{
}
static inline void mmiotrace_iounmap(volatile void __iomem *addr)
{
}
#endif /* CONFIG_MMIOTRACE_HOOKS */
enum mm_io_opcode {
MMIO_READ = 0x1, /* struct mmiotrace_rw */
MMIO_WRITE = 0x2, /* struct mmiotrace_rw */
MMIO_PROBE = 0x3, /* struct mmiotrace_map */
MMIO_UNPROBE = 0x4, /* struct mmiotrace_map */
MMIO_MARKER = 0x5, /* raw char data */
MMIO_UNKNOWN_OP = 0x6, /* struct mmiotrace_rw */
};
struct mmiotrace_rw {
resource_size_t phys; /* PCI address of register */
unsigned long value;
unsigned long pc; /* optional program counter */
int map_id;
unsigned char opcode; /* one of MMIO_{READ,WRITE,UNKNOWN_OP} */
unsigned char width; /* size of register access in bytes */
};
struct mmiotrace_map {
resource_size_t phys; /* base address in PCI space */
unsigned long virt; /* base virtual address */
unsigned long len; /* mapping size */
int map_id;
unsigned char opcode; /* MMIO_PROBE or MMIO_UNPROBE */
};
/* in kernel/trace/trace_mmiotrace.c */
extern void enable_mmiotrace(void);
extern void disable_mmiotrace(void);
extern void mmio_trace_rw(struct mmiotrace_rw *rw);
extern void mmio_trace_mapping(struct mmiotrace_map *map);
#endif /* MMIOTRACE_H */

1
kernel/trace/Makefile
View File

@ -18,5 +18,6 @@ obj-$(CONFIG_FTRACE) += trace_functions.o
obj-$(CONFIG_IRQSOFF_TRACER) += trace_irqsoff.o
obj-$(CONFIG_PREEMPT_TRACER) += trace_irqsoff.o
obj-$(CONFIG_SCHED_TRACER) += trace_sched_wakeup.o
obj-$(CONFIG_MMIOTRACE) += trace_mmiotrace.o
libftrace-y := ftrace.o

42
kernel/trace/trace.c
View File

@ -848,6 +848,48 @@ ftrace(struct trace_array *tr, struct trace_array_cpu *data,
trace_function(tr, data, ip, parent_ip, flags);
}
#ifdef CONFIG_MMIOTRACE
void __trace_mmiotrace_rw(struct trace_array *tr, struct trace_array_cpu *data,
struct mmiotrace_rw *rw)
{
struct trace_entry *entry;
unsigned long irq_flags;
raw_local_irq_save(irq_flags);
__raw_spin_lock(&data->lock);
entry = tracing_get_trace_entry(tr, data);
tracing_generic_entry_update(entry, 0);
entry->type = TRACE_MMIO_RW;
entry->mmiorw = *rw;
__raw_spin_unlock(&data->lock);
raw_local_irq_restore(irq_flags);
trace_wake_up();
}
void __trace_mmiotrace_map(struct trace_array *tr, struct trace_array_cpu *data,
struct mmiotrace_map *map)
{
struct trace_entry *entry;
unsigned long irq_flags;
raw_local_irq_save(irq_flags);
__raw_spin_lock(&data->lock);
entry = tracing_get_trace_entry(tr, data);
tracing_generic_entry_update(entry, 0);
entry->type = TRACE_MMIO_MAP;
entry->mmiomap = *map;
__raw_spin_unlock(&data->lock);
raw_local_irq_restore(irq_flags);
trace_wake_up();
}
#endif
void __trace_stack(struct trace_array *tr,
struct trace_array_cpu *data,
unsigned long flags,

14
kernel/trace/trace.h
View File

@ -5,6 +5,7 @@
#include <asm/atomic.h>
#include <linux/sched.h>
#include <linux/clocksource.h>
#include <linux/mmiotrace.h>
enum trace_type {
__TRACE_FIRST_TYPE = 0,
@ -14,6 +15,8 @@ enum trace_type {
TRACE_WAKE,
TRACE_STACK,
TRACE_SPECIAL,
TRACE_MMIO_RW,
TRACE_MMIO_MAP,
__TRACE_LAST_TYPE
};
@ -75,6 +78,8 @@ struct trace_entry {
struct ctx_switch_entry ctx;
struct special_entry special;
struct stack_entry stack;
struct mmiotrace_rw mmiorw;
struct mmiotrace_map mmiomap;
};
};
@ -255,6 +260,15 @@ extern unsigned long ftrace_update_tot_cnt;
extern int DYN_FTRACE_TEST_NAME(void);
#endif
#ifdef CONFIG_MMIOTRACE
extern void __trace_mmiotrace_rw(struct trace_array *tr,
struct trace_array_cpu *data,
struct mmiotrace_rw *rw);
extern void __trace_mmiotrace_map(struct trace_array *tr,
struct trace_array_cpu *data,
struct mmiotrace_map *map);
#endif
#ifdef CONFIG_FTRACE_STARTUP_TEST
#ifdef CONFIG_FTRACE
extern int trace_selftest_startup_function(struct tracer *trace,

295
kernel/trace/trace_mmiotrace.c Normal file
View File

@ -0,0 +1,295 @@
/*
* Memory mapped I/O tracing
*
* Copyright (C) 2008 Pekka Paalanen <pq@iki.fi>
*/
#define DEBUG 1
#include <linux/kernel.h>
#include <linux/mmiotrace.h>
#include <linux/pci.h>
#include "trace.h"
struct header_iter {
struct pci_dev *dev;
};
static struct trace_array *mmio_trace_array;
static bool overrun_detected;
static void mmio_reset_data(struct trace_array *tr)
{
int cpu;
overrun_detected = false;
tr->time_start = ftrace_now(tr->cpu);
for_each_online_cpu(cpu)
tracing_reset(tr->data[cpu]);
}
static void mmio_trace_init(struct trace_array *tr)
{
pr_debug("in %s\n", __func__);
mmio_trace_array = tr;
if (tr->ctrl) {
mmio_reset_data(tr);
enable_mmiotrace();
}
}
static void mmio_trace_reset(struct trace_array *tr)
{
pr_debug("in %s\n", __func__);
if (tr->ctrl)
disable_mmiotrace();
mmio_reset_data(tr);
mmio_trace_array = NULL;
}
static void mmio_trace_ctrl_update(struct trace_array *tr)
{
pr_debug("in %s\n", __func__);
if (tr->ctrl) {
mmio_reset_data(tr);
enable_mmiotrace();
} else {
disable_mmiotrace();
}
}
static int mmio_print_pcidev(struct trace_seq *s, const struct pci_dev *dev)
{
int ret = 0;
int i;
resource_size_t start, end;
const struct pci_driver *drv = pci_dev_driver(dev);
/* XXX: incomplete checks for trace_seq_printf() return value */
ret += trace_seq_printf(s, "PCIDEV %02x%02x %04x%04x %x",
dev->bus->number, dev->devfn,
dev->vendor, dev->device, dev->irq);
/*
* XXX: is pci_resource_to_user() appropriate, since we are
* supposed to interpret the __ioremap() phys_addr argument based on
* these printed values?
*/
for (i = 0; i < 7; i++) {
pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
ret += trace_seq_printf(s, " %llx",
(unsigned long long)(start |
(dev->resource[i].flags & PCI_REGION_FLAG_MASK)));
}
for (i = 0; i < 7; i++) {
pci_resource_to_user(dev, i, &dev->resource[i], &start, &end);
ret += trace_seq_printf(s, " %llx",
dev->resource[i].start < dev->resource[i].end ?
(unsigned long long)(end - start) + 1 : 0);
}
if (drv)
ret += trace_seq_printf(s, " %s\n", drv->name);
else
ret += trace_seq_printf(s, " \n");
return ret;
}
static void destroy_header_iter(struct header_iter *hiter)
{
if (!hiter)
return;
pci_dev_put(hiter->dev);
kfree(hiter);
}
static void mmio_pipe_open(struct trace_iterator *iter)
{
struct header_iter *hiter;
struct trace_seq *s = &iter->seq;
trace_seq_printf(s, "VERSION 20070824\n");
hiter = kzalloc(sizeof(*hiter), GFP_KERNEL);
if (!hiter)
return;
hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, NULL);
iter->private = hiter;
}
/* XXX: This is not called when the pipe is closed! */
static void mmio_close(struct trace_iterator *iter)
{
struct header_iter *hiter = iter->private;
destroy_header_iter(hiter);
iter->private = NULL;
}
static unsigned long count_overruns(struct trace_iterator *iter)
{
int cpu;
unsigned long cnt = 0;
for_each_online_cpu(cpu) {
cnt += iter->overrun[cpu];
iter->overrun[cpu] = 0;
}
return cnt;
}
static ssize_t mmio_read(struct trace_iterator *iter, struct file *filp,
char __user *ubuf, size_t cnt, loff_t *ppos)
{
ssize_t ret;
struct header_iter *hiter = iter->private;
struct trace_seq *s = &iter->seq;
unsigned long n;
n = count_overruns(iter);
if (n) {
/* XXX: This is later than where events were lost. */
trace_seq_printf(s, "MARK 0.000000 Lost %lu events.\n", n);
if (!overrun_detected)
pr_warning("mmiotrace has lost events.\n");
overrun_detected = true;
goto print_out;
}
if (!hiter)
return 0;
mmio_print_pcidev(s, hiter->dev);
hiter->dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, hiter->dev);
if (!hiter->dev) {
destroy_header_iter(hiter);
iter->private = NULL;
}
print_out:
ret = trace_seq_to_user(s, ubuf, cnt);
return (ret == -EBUSY) ? 0 : ret;
}
static int mmio_print_rw(struct trace_iterator *iter)
{
struct trace_entry *entry = iter->ent;
struct mmiotrace_rw *rw = &entry->mmiorw;
struct trace_seq *s = &iter->seq;
unsigned long long t = ns2usecs(entry->t);
unsigned long usec_rem = do_div(t, 1000000ULL);
unsigned secs = (unsigned long)t;
int ret = 1;
switch (entry->mmiorw.opcode) {
case MMIO_READ:
ret = trace_seq_printf(s,
"R %d %lu.%06lu %d 0x%llx 0x%lx 0x%lx %d\n",
rw->width, secs, usec_rem, rw->map_id,
(unsigned long long)rw->phys,
rw->value, rw->pc, 0);
break;
case MMIO_WRITE:
ret = trace_seq_printf(s,
"W %d %lu.%06lu %d 0x%llx 0x%lx 0x%lx %d\n",
rw->width, secs, usec_rem, rw->map_id,
(unsigned long long)rw->phys,
rw->value, rw->pc, 0);
break;
case MMIO_UNKNOWN_OP:
ret = trace_seq_printf(s,
"UNKNOWN %lu.%06lu %d 0x%llx %02x,%02x,%02x 0x%lx %d\n",
secs, usec_rem, rw->map_id,
(unsigned long long)rw->phys,
(rw->value >> 16) & 0xff, (rw->value >> 8) & 0xff,
(rw->value >> 0) & 0xff, rw->pc, 0);
break;
default:
ret = trace_seq_printf(s, "rw what?\n");
break;
}
if (ret)
return 1;
return 0;
}
static int mmio_print_map(struct trace_iterator *iter)
{
struct trace_entry *entry = iter->ent;
struct mmiotrace_map *m = &entry->mmiomap;
struct trace_seq *s = &iter->seq;
unsigned long long t = ns2usecs(entry->t);
unsigned long usec_rem = do_div(t, 1000000ULL);
unsigned secs = (unsigned long)t;
int ret = 1;
switch (entry->mmiorw.opcode) {
case MMIO_PROBE:
ret = trace_seq_printf(s,
"MAP %lu.%06lu %d 0x%llx 0x%lx 0x%lx 0x%lx %d\n",
secs, usec_rem, m->map_id,
(unsigned long long)m->phys, m->virt, m->len,
0UL, 0);
break;
case MMIO_UNPROBE:
ret = trace_seq_printf(s,
"UNMAP %lu.%06lu %d 0x%lx %d\n",
secs, usec_rem, m->map_id, 0UL, 0);
break;
default:
ret = trace_seq_printf(s, "map what?\n");
break;
}
if (ret)
return 1;
return 0;
}
/* return 0 to abort printing without consuming current entry in pipe mode */
static int mmio_print_line(struct trace_iterator *iter)
{
switch (iter->ent->type) {
case TRACE_MMIO_RW:
return mmio_print_rw(iter);
case TRACE_MMIO_MAP:
return mmio_print_map(iter);
default:
return 1; /* ignore unknown entries */
}
}
static struct tracer mmio_tracer __read_mostly =
{
.name = "mmiotrace",
.init = mmio_trace_init,
.reset = mmio_trace_reset,
.pipe_open = mmio_pipe_open,
.close = mmio_close,
.read = mmio_read,
.ctrl_update = mmio_trace_ctrl_update,
.print_line = mmio_print_line,
};
__init static int init_mmio_trace(void)
{
return register_tracer(&mmio_tracer);
}
device_initcall(init_mmio_trace);
void mmio_trace_rw(struct mmiotrace_rw *rw)
{
struct trace_array *tr = mmio_trace_array;
struct trace_array_cpu *data = tr->data[smp_processor_id()];
__trace_mmiotrace_rw(tr, data, rw);
}
void mmio_trace_mapping(struct mmiotrace_map *map)
{
struct trace_array *tr = mmio_trace_array;
struct trace_array_cpu *data;
preempt_disable();
data = tr->data[smp_processor_id()];
__trace_mmiotrace_map(tr, data, map);
preempt_enable();
}