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-rw-r--r--arch/x86/Kconfig.debug27
-rw-r--r--arch/x86/kernel/Makefile2
-rw-r--r--arch/x86/kernel/init_task.c1
-rw-r--r--arch/x86/kernel/mmiotrace/Makefile4
-rw-r--r--arch/x86/kernel/mmiotrace/kmmio.c391
-rw-r--r--arch/x86/kernel/mmiotrace/kmmio.h58
-rw-r--r--arch/x86/kernel/mmiotrace/mmio-mod.c527
-rw-r--r--arch/x86/kernel/mmiotrace/pf_in.c489
-rw-r--r--arch/x86/kernel/mmiotrace/pf_in.h39
-rw-r--r--arch/x86/kernel/mmiotrace/testmmiotrace.c77
-rw-r--r--include/linux/mmiotrace.h62
11 files changed, 1677 insertions, 0 deletions
diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug
index 9431a839984..7c6496e2225 100644
--- a/arch/x86/Kconfig.debug
+++ b/arch/x86/Kconfig.debug
@@ -176,6 +176,33 @@ config PAGE_FAULT_HANDLERS
register a function that is called on every page fault. Custom
handlers are used by some debugging and reverse engineering tools.
+config MMIOTRACE
+ tristate "Memory mapped IO tracing"
+ depends on DEBUG_KERNEL && PAGE_FAULT_HANDLERS && RELAY && DEBUG_FS
+ default n
+ help
+ This will build a kernel module called mmiotrace.
+
+ Mmiotrace traces Memory Mapped I/O access and is meant for debugging
+ and reverse engineering. The kernel module offers wrapped
+ versions of the ioremap family of functions. The driver to be traced
+ must be modified to call these wrappers. A user space program is
+ required to collect the MMIO data.
+
+ See http://nouveau.freedesktop.org/wiki/MmioTrace
+ If you are not helping to develop drivers, say N.
+
+config MMIOTRACE_TEST
+ tristate "Test module for mmiotrace"
+ depends on MMIOTRACE && m
+ default n
+ 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:
#
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 739d49acd2f..a51ac153685 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -79,6 +79,8 @@ obj-$(CONFIG_KGDB) += kgdb.o
obj-$(CONFIG_VM86) += vm86_32.o
obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
+obj-$(CONFIG_MMIOTRACE) += mmiotrace/
+
obj-$(CONFIG_HPET_TIMER) += hpet.o
obj-$(CONFIG_K8_NB) += k8.o
diff --git a/arch/x86/kernel/init_task.c b/arch/x86/kernel/init_task.c
index a4f93b4120c..027a5b6a12b 100644
--- a/arch/x86/kernel/init_task.c
+++ b/arch/x86/kernel/init_task.c
@@ -15,6 +15,7 @@ static struct signal_struct init_signals = INIT_SIGNALS(init_signals);
static struct sighand_struct init_sighand = INIT_SIGHAND(init_sighand);
struct mm_struct init_mm = INIT_MM(init_mm);
EXPORT_UNUSED_SYMBOL(init_mm); /* will be removed in 2.6.26 */
+EXPORT_SYMBOL_GPL(init_mm);
/*
* Initial thread structure.
diff --git a/arch/x86/kernel/mmiotrace/Makefile b/arch/x86/kernel/mmiotrace/Makefile
new file mode 100644
index 00000000000..d6905f7f981
--- /dev/null
+++ b/arch/x86/kernel/mmiotrace/Makefile
@@ -0,0 +1,4 @@
+obj-$(CONFIG_MMIOTRACE) += mmiotrace.o
+mmiotrace-objs := pf_in.o kmmio.o mmio-mod.o
+
+obj-$(CONFIG_MMIOTRACE_TEST) += testmmiotrace.o
diff --git a/arch/x86/kernel/mmiotrace/kmmio.c b/arch/x86/kernel/mmiotrace/kmmio.c
new file mode 100644
index 00000000000..8ba48f9c91b
--- /dev/null
+++ b/arch/x86/kernel/mmiotrace/kmmio.c
@@ -0,0 +1,391 @@
+/* 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/version.h>
+#include <linux/spinlock.h>
+#include <linux/hash.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/uaccess.h>
+#include <linux/ptrace.h>
+#include <linux/preempt.h>
+#include <asm/io.h>
+#include <asm/cacheflush.h>
+#include <asm/errno.h>
+#include <asm/tlbflush.h>
+
+#include "kmmio.h"
+
+#define KMMIO_HASH_BITS 6
+#define KMMIO_TABLE_SIZE (1 << KMMIO_HASH_BITS)
+#define KMMIO_PAGE_HASH_BITS 4
+#define KMMIO_PAGE_TABLE_SIZE (1 << KMMIO_PAGE_HASH_BITS)
+
+struct kmmio_context {
+ struct kmmio_fault_page *fpage;
+ struct kmmio_probe *probe;
+ unsigned long saved_flags;
+ int active;
+};
+
+static int kmmio_page_fault(struct pt_regs *regs, unsigned long error_code,
+ unsigned long address);
+static int kmmio_die_notifier(struct notifier_block *nb, unsigned long val,
+ void *args);
+
+static DEFINE_SPINLOCK(kmmio_lock);
+
+/* These are protected by kmmio_lock */
+unsigned int kmmio_count;
+static unsigned int handler_registered;
+static struct list_head kmmio_page_table[KMMIO_PAGE_TABLE_SIZE];
+static LIST_HEAD(kmmio_probes);
+
+static struct kmmio_context kmmio_ctx[NR_CPUS];
+
+static struct pf_handler kmmio_pf_hook = {
+ .handler = kmmio_page_fault
+};
+
+static struct notifier_block nb_die = {
+ .notifier_call = kmmio_die_notifier
+};
+
+int init_kmmio(void)
+{
+ int i;
+ for (i = 0; i < KMMIO_PAGE_TABLE_SIZE; i++)
+ INIT_LIST_HEAD(&kmmio_page_table[i]);
+
+ register_die_notifier(&nb_die);
+ return 0;
+}
+
+void cleanup_kmmio(void)
+{
+ /*
+ * Assume the following have been already cleaned by calling
+ * unregister_kmmio_probe() appropriately:
+ * kmmio_page_table, kmmio_probes
+ */
+ if (handler_registered) {
+ unregister_page_fault_handler(&kmmio_pf_hook);
+ synchronize_rcu();
+ }
+ unregister_die_notifier(&nb_die);
+}
+
+/*
+ * 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 kmmio_lock. */
+static struct kmmio_probe *get_kmmio_probe(unsigned long addr)
+{
+ struct kmmio_probe *p;
+ list_for_each_entry(p, &kmmio_probes, list) {
+ if (addr >= p->addr && addr <= (p->addr + p->len))
+ return p;
+ }
+ return NULL;
+}
+
+static struct kmmio_fault_page *get_kmmio_fault_page(unsigned long page)
+{
+ struct list_head *head, *tmp;
+
+ page &= PAGE_MASK;
+ head = &kmmio_page_table[hash_long(page, KMMIO_PAGE_HASH_BITS)];
+ list_for_each(tmp, head) {
+ struct kmmio_fault_page *p
+ = list_entry(tmp, struct kmmio_fault_page, list);
+ if (p->page == page)
+ return p;
+ }
+
+ return NULL;
+}
+
+static void arm_kmmio_fault_page(unsigned long page, int *large)
+{
+ unsigned long address = page & PAGE_MASK;
+ pgd_t *pgd = pgd_offset_k(address);
+ pud_t *pud = pud_offset(pgd, address);
+ pmd_t *pmd = pmd_offset(pud, address);
+ pte_t *pte = pte_offset_kernel(pmd, address);
+
+ if (pmd_large(*pmd)) {
+ set_pmd(pmd, __pmd(pmd_val(*pmd) & ~_PAGE_PRESENT));
+ if (large)
+ *large = 1;
+ } else {
+ set_pte(pte, __pte(pte_val(*pte) & ~_PAGE_PRESENT));
+ }
+
+ __flush_tlb_one(page);
+}
+
+static void disarm_kmmio_fault_page(unsigned long page, int *large)
+{
+ unsigned long address = page & PAGE_MASK;
+ pgd_t *pgd = pgd_offset_k(address);
+ pud_t *pud = pud_offset(pgd, address);
+ pmd_t *pmd = pmd_offset(pud, address);
+ pte_t *pte = pte_offset_kernel(pmd, address);
+
+ if (large && *large) {
+ set_pmd(pmd, __pmd(pmd_val(*pmd) | _PAGE_PRESENT));
+ *large = 0;
+ } else {
+ set_pte(pte, __pte(pte_val(*pte) | _PAGE_PRESENT));
+ }
+
+ __flush_tlb_one(page);
+}
+
+/*
+ * Interrupts are disabled on entry as trap3 is an interrupt gate
+ * and they remain disabled thorough out this function.
+ */
+static int kmmio_handler(struct pt_regs *regs, unsigned long addr)
+{
+ struct kmmio_context *ctx;
+ int cpu;
+
+ /*
+ * 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.
+ *
+ * XXX what if an interrupt occurs between returning from
+ * do_page_fault() and entering the single-step exception handler?
+ * And that interrupt triggers a kmmio trap?
+ */
+ preempt_disable();
+ cpu = smp_processor_id();
+ ctx = &kmmio_ctx[cpu];
+
+ /* interrupts disabled and CPU-local data => atomicity guaranteed. */
+ if (ctx->active) {
+ /*
+ * This avoids a deadlock with kmmio_lock.
+ * If this page fault really was due to kmmio trap,
+ * all hell breaks loose.
+ */
+ printk(KERN_EMERG "mmiotrace: recursive probe hit on CPU %d, "
+ "for address %lu. Ignoring.\n",
+ cpu, addr);
+ goto no_kmmio;
+ }
+ ctx->active++;
+
+ /*
+ * Acquire the kmmio lock to prevent changes affecting
+ * get_kmmio_fault_page() and get_kmmio_probe(), since we save their
+ * returned pointers.
+ * The lock is released in post_kmmio_handler().
+ * XXX: could/should get_kmmio_*() be using RCU instead of spinlock?
+ */
+ spin_lock(&kmmio_lock);
+
+ ctx->fpage = get_kmmio_fault_page(addr);
+ if (!ctx->fpage) {
+ /* this page fault is not caused by kmmio */
+ goto no_kmmio_locked;
+ }
+
+ ctx->probe = get_kmmio_probe(addr);
+ ctx->saved_flags = (regs->flags & (TF_MASK|IF_MASK));
+
+ if (ctx->probe && ctx->probe->pre_handler)
+ ctx->probe->pre_handler(ctx->probe, regs, addr);
+
+ regs->flags |= TF_MASK;
+ regs->flags &= ~IF_MASK;
+
+ /* We hold lock, now we set present bit in PTE and single step. */
+ disarm_kmmio_fault_page(ctx->fpage->page, NULL);
+
+ return 1;
+
+no_kmmio_locked:
+ spin_unlock(&kmmio_lock);
+ ctx->active--;
+no_kmmio:
+ preempt_enable_no_resched();
+ /* page fault not handled by kmmio */
+ return 0;
+}
+
+/*
+ * Interrupts are disabled on entry as trap1 is an interrupt gate
+ * and they remain disabled thorough out this function.
+ * And we hold kmmio lock.
+ */
+static int post_kmmio_handler(unsigned long condition, struct pt_regs *regs)
+{
+ int cpu = smp_processor_id();
+ struct kmmio_context *ctx = &kmmio_ctx[cpu];
+
+ if (!ctx->active)
+ return 0;
+
+ 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 &= ~TF_MASK;
+ regs->flags |= ctx->saved_flags;
+
+ /* These were acquired in kmmio_handler(). */
+ ctx->active--;
+ spin_unlock(&kmmio_lock);
+ 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 & TF_MASK)
+ return 0;
+
+ return 1;
+}
+
+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) {
+ f->count++;
+ return 0;
+ }
+
+ f = kmalloc(sizeof(*f), GFP_ATOMIC);
+ if (!f)
+ return -1;
+
+ f->count = 1;
+ f->page = page;
+ list_add(&f->list,
+ &kmmio_page_table[hash_long(f->page, KMMIO_PAGE_HASH_BITS)]);
+
+ arm_kmmio_fault_page(f->page, NULL);
+
+ return 0;
+}
+
+static void release_kmmio_fault_page(unsigned long page)
+{
+ struct kmmio_fault_page *f;
+
+ page &= PAGE_MASK;
+ f = get_kmmio_fault_page(page);
+ if (!f)
+ return;
+
+ f->count--;
+ if (!f->count) {
+ disarm_kmmio_fault_page(f->page, NULL);
+ list_del(&f->list);
+ }
+}
+
+int register_kmmio_probe(struct kmmio_probe *p)
+{
+ int ret = 0;
+ unsigned long size = 0;
+
+ spin_lock_irq(&kmmio_lock);
+ kmmio_count++;
+ if (get_kmmio_probe(p->addr)) {
+ ret = -EEXIST;
+ goto out;
+ }
+ list_add(&p->list, &kmmio_probes);
+ /*printk("adding fault pages...\n");*/
+ while (size < p->len) {
+ if (add_kmmio_fault_page(p->addr + size))
+ printk(KERN_ERR "mmio: Unable to set page fault.\n");
+ size += PAGE_SIZE;
+ }
+
+ if (!handler_registered) {
+ register_page_fault_handler(&kmmio_pf_hook);
+ handler_registered++;
+ }
+
+out:
+ spin_unlock_irq(&kmmio_lock);
+ /*
+ * XXX: What should I do here?
+ * Here was a call to global_flush_tlb(), but it does not exist
+ * anymore.
+ */
+ return ret;
+}
+
+void unregister_kmmio_probe(struct kmmio_probe *p)
+{
+ unsigned long size = 0;
+
+ spin_lock_irq(&kmmio_lock);
+ while (size < p->len) {
+ release_kmmio_fault_page(p->addr + size);
+ size += PAGE_SIZE;
+ }
+ list_del(&p->list);
+ kmmio_count--;
+ spin_unlock_irq(&kmmio_lock);
+}
+
+/*
+ * According to 2.6.20, mainly x86_64 arch:
+ * This is being called from do_page_fault(), via the page fault notifier
+ * chain. The chain is called for both user space faults and kernel space
+ * faults (address >= TASK_SIZE64), except not on faults serviced by
+ * vmalloc_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.
+ * The page fault hook functionality has put us inside RCU read lock.
+ *
+ * Local interrupts are disabled, so preemption cannot happen.
+ * Do not enable interrupts, do not sleep, and watch out for other CPUs.
+ */
+static int kmmio_page_fault(struct pt_regs *regs, unsigned long error_code,
+ unsigned long address)
+{
+ if (is_kmmio_active())
+ if (kmmio_handler(regs, address) == 1)
+ return -1;
+ return 0;
+}
+
+static int kmmio_die_notifier(struct notifier_block *nb, unsigned long val,
+ void *args)
+{
+ struct die_args *arg = args;
+
+ if (val == DIE_DEBUG)
+ if (post_kmmio_handler(arg->err, arg->regs) == 1)
+ return NOTIFY_STOP;
+
+ return NOTIFY_DONE;
+}
diff --git a/arch/x86/kernel/mmiotrace/kmmio.h b/arch/x86/kernel/mmiotrace/kmmio.h
new file mode 100644
index 00000000000..85b7f68a3b8
--- /dev/null
+++ b/arch/x86/kernel/mmiotrace/kmmio.h
@@ -0,0 +1,58 @@
+#ifndef _LINUX_KMMIO_H
+#define _LINUX_KMMIO_H
+
+#include <linux/list.h>
+#include <linux/notifier.h>
+#include <linux/smp.h>
+#include <linux/types.h>
+#include <linux/ptrace.h>
+#include <linux/version.h>
+#include <linux/kdebug.h>
+
+struct kmmio_probe;
+struct kmmio_fault_page;
+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;
+
+ /* start location of the probe point */
+ unsigned long addr;
+
+ /* length of the probe region */
+ unsigned long len;
+
+ /* Called before addr is executed. */
+ kmmio_pre_handler_t pre_handler;
+
+ /* Called after addr is executed, unless... */
+ kmmio_post_handler_t post_handler;
+};
+
+struct kmmio_fault_page {
+ struct list_head list;
+
+ /* location of the fault page */
+ unsigned long page;
+
+ int count;
+};
+
+/* kmmio is active by some kmmio_probes? */
+static inline int is_kmmio_active(void)
+{
+ extern unsigned int kmmio_count;
+ return kmmio_count;
+}
+
+int init_kmmio(void);
+void cleanup_kmmio(void);
+int register_kmmio_probe(struct kmmio_probe *p);
+void unregister_kmmio_probe(struct kmmio_probe *p);
+
+#endif /* _LINUX_KMMIO_H */
diff --git a/arch/x86/kernel/mmiotrace/mmio-mod.c b/arch/x86/kernel/mmiotrace/mmio-mod.c
new file mode 100644
index 00000000000..73561fe85f0
--- /dev/null
+++ b/arch/x86/kernel/mmiotrace/mmio-mod.c
@@ -0,0 +1,527 @@
+/*
+ * 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.
+ */
+#include <linux/module.h>
+#include <linux/relay.h>
+#include <linux/debugfs.h>
+#include <linux/proc_fs.h>
+#include <asm/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 "kmmio.h"
+#include "pf_in.h"
+
+/* This app's relay channel files will appear in /debug/mmio-trace */
+#define APP_DIR "mmio-trace"
+/* the marker injection file in /proc */
+#define MARKER_FILE "mmio-marker"
+
+#define MODULE_NAME "mmiotrace"
+
+struct trap_reason {
+ unsigned long addr;
+ unsigned long ip;
+ enum reason_type type;
+ int active_traces;
+};
+
+static struct trap_reason pf_reason[NR_CPUS];
+static struct mm_io_header_rw cpu_trace[NR_CPUS];
+
+static struct file_operations mmio_fops = {
+ .owner = THIS_MODULE,
+};
+
+static const size_t subbuf_size = 256*1024;
+static struct rchan *chan;
+static struct dentry *dir;
+static int suspended; /* XXX should this be per cpu? */
+static struct proc_dir_entry *proc_marker_file;
+
+/* module parameters */
+static unsigned int n_subbufs = 32*4;
+static unsigned long filter_offset;
+static int nommiotrace;
+static int ISA_trace;
+static int trace_pc;
+
+module_param(n_subbufs, uint, 0);
+module_param(filter_offset, ulong, 0);
+module_param(nommiotrace, bool, 0);
+module_param(ISA_trace, bool, 0);
+module_param(trace_pc, bool, 0);
+
+MODULE_PARM_DESC(n_subbufs, "Number of 256kB buffers, default 128.");
+MODULE_PARM_DESC(filter_offset, "Start address of traced mappings.");
+MODULE_PARM_DESC(nommiotrace, "Disable actual MMIO tracing.");
+MODULE_PARM_DESC(ISA_trace, "Do not exclude the low ISA range.");
+MODULE_PARM_DESC(trace_pc, "Record address of faulting instructions.");
+
+static void record_timestamp(struct mm_io_header *header)
+{
+ struct timespec now;
+
+ getnstimeofday(&now);
+ header->sec = now.tv_sec;
+ header->nsec = now.tv_nsec;
+}
+
+/*
+ * Write callback for the /proc entry:
+ * Read a marker and write it to the mmio trace log
+ */
+static int write_marker(struct file *file, const char __user *buffer,
+ unsigned long count, void *data)
+{
+ char *event = NULL;
+ struct mm_io_header *headp;
+ int 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;
+ record_timestamp(headp);
+
+ if (copy_from_user(event + sizeof(*headp), buffer, len)) {
+ kfree(event);
+ return -EFAULT;
+ }
+
+ relay_write(chan, event, sizeof(*headp) + len);
+ kfree(event);
+ return len;
+}
+
+static void print_pte(unsigned long address)
+{
+ pgd_t *pgd = pgd_offset_k(address);
+ pud_t *pud = pud_offset(pgd, address);
+ pmd_t *pmd = pmd_offset(pud, address);
+ if (pmd_large(*pmd)) {
+ printk(KERN_EMERG MODULE_NAME ": 4MB pages are not "
+ "currently supported: %lx\n",
+ address);
+ BUG();
+ }
+ printk(KERN_DEBUG MODULE_NAME ": pte for 0x%lx: 0x%lx 0x%lx\n",
+ address,
+ pte_val(*pte_offset_kernel(pmd, address)),
+ pte_val(*pte_offset_kernel(pmd, address)) & _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 unsigned long cpu = smp_processor_id();
+ printk(KERN_EMERG MODULE_NAME ": unexpected fault for address: %lx, "
+ "last fault for address: %lx\n",
+ addr, pf_reason[cpu].addr);
+ print_pte(addr);
+#ifdef __i386__
+ print_symbol(KERN_EMERG "faulting EIP is at %s\n", regs->ip);
+ print_symbol(KERN_EMERG "last faulting EIP was at %s\n",
+ pf_reason[cpu].ip);
+ printk(KERN_EMERG
+ "eax: %08lx ebx: %08lx ecx: %08lx edx: %08lx\n",
+ regs->ax, regs->bx, regs->cx, regs->dx);
+ printk(KERN_EMERG
+ "esi: %08lx edi: %08lx ebp: %08lx esp: %08lx\n",
+ regs->si, regs->di, regs->bp, regs->sp);
+#else
+ print_symbol(KERN_EMERG "faulting RIP is at %s\n", regs->ip);
+ print_symbol(KERN_EMERG "last faulting RIP was at %s\n",
+ pf_reason[cpu].ip);
+ printk(KERN_EMERG "rax: %016lx rcx: %016lx rdx: %016lx\n",
+ regs->ax, regs->cx, regs->dx);
+ printk(KERN_EMERG "rsi: %016lx rdi: %016lx "
+ "rbp: %016lx rsp: %016lx\n",
+ regs->si, regs->di, regs->bp, regs->sp);
+#endif
+ BUG();
+}
+
+static void pre(struct kmmio_probe *p, struct pt_regs *regs,
+ unsigned long addr)
+{
+ const unsigned long cpu = smp_processor_id();
+ const unsigned long instptr = instruction_pointer(regs);
+ const enum reason_type type = get_ins_type(instptr);
+
+ /* it doesn't make sense to have more than one active trace per cpu */
+ if (pf_reason[cpu].active_traces)
+ die_kmmio_nesting_error(regs, addr);
+ else
+ pf_reason[cpu].active_traces++;
+
+ pf_reason[cpu].type = type;
+ pf_reason[cpu].addr = addr;
+ pf_reason[cpu].ip = instptr;
+
+ cpu_trace[cpu].header.type = MMIO_MAGIC;
+ cpu_trace[cpu].header.pid = 0;
+ cpu_trace[cpu].header.data_len = sizeof(struct mm_io_rw);
+ cpu_trace[cpu].rw.address = addr;
+
+ /*
+ * Only record the program counter when requested.
+ * It may taint clean-room reverse engineering.
+ */
+ if (trace_pc)
+ cpu_trace[cpu].rw.pc = instptr;
+ else
+ cpu_trace[cpu].rw.pc = 0;
+
+ record_timestamp(&cpu_trace[cpu].header);
+
+ switch (type) {
+ case REG_READ:
+ cpu_trace[cpu].header.type |=
+ (MMIO_READ << MMIO_OPCODE_SHIFT) |
+ (get_ins_mem_width(instptr) << MMIO_WIDTH_SHIFT);
+ break;
+ case REG_WRITE:
+ cpu_trace[cpu].header.type |=
+ (MMIO_WRITE << MMIO_OPCODE_SHIFT) |
+ (get_ins_mem_width(instptr) << MMIO_WIDTH_SHIFT);
+ cpu_trace[cpu].rw.value = get_ins_reg_val(instptr, regs);
+ break;
+ case IMM_WRITE:
+ cpu_trace[cpu].header.type |=
+ (MMIO_WRITE << MMIO_OPCODE_SHIFT) |
+ (get_ins_mem_width(instptr) << MMIO_WIDTH_SHIFT);
+ cpu_trace[cpu].rw.value = get_ins_imm_val(instptr);
+ break;
+ default:
+ {
+ unsigned char *ip = (unsigned char *)instptr;
+ cpu_trace[cpu].header.type |=
+ (MMIO_UNKNOWN_OP << MMIO_OPCODE_SHIFT);
+ cpu_trace[cpu].rw.value = (*ip) << 16 |
+ *(ip + 1) << 8 |
+ *(ip + 2);
+ }
+ }
+}
+
+static void post(struct kmmio_probe *p, unsigned long condition,
+ struct pt_regs *regs)
+{
+ const unsigned long cpu = smp_processor_id();
+
+ /* this should always return the active_trace count to 0 */
+ pf_reason[cpu].active_traces--;
+ if (pf_reason[cpu].active_traces) {
+ printk(KERN_EMERG MODULE_NAME ": unexpected post handler");
+ BUG();
+ }
+
+ switch (pf_reason[cpu].type) {
+ case REG_READ:
+ cpu_trace[cpu].rw.value = get_ins_reg_val(pf_reason[cpu].ip,
+ regs);
+ break;
+ default:
+ break;
+ }
+ relay_write(chan, &cpu_trace[cpu], sizeof(struct mm_io_header_rw));
+}
+
+/*
+ * subbuf_start() relay callback.
+ *
+ * Defined so that we know when events are dropped due to the buffer-full
+ * condition.
+ */
+static int subbuf_start_handler(struct rchan_buf *buf, void *subbuf,
+ void *prev_subbuf, size_t prev_padding)
+{
+ if (relay_buf_full(buf)) {
+ if (!suspended) {
+ suspended = 1;
+ printk(KERN_ERR MODULE_NAME
+ ": cpu %d buffer full!!!\n",
+ smp_processor_id());
+ }
+ return 0;
+ } else if (suspended) {
+ suspended = 0;
+ printk(KERN_ERR MODULE_NAME
+ ": cpu %d buffer no longer full.\n",
+ smp_processor_id());
+ }
+
+ return 1;
+}
+
+/* file_create() callback. Creates relay file in debugfs. */
+static struct dentry *create_buf_file_handler(const char *filename,
+ struct dentry *parent,
+ int mode,
+ struct rchan_buf *buf,
+ int *is_global)
+{
+ struct dentry *buf_file;
+
+ mmio_fops.read = relay_file_operations.read;
+ mmio_fops.open = relay_file_operations.open;
+ mmio_fops.poll = relay_file_operations.poll;
+ mmio_fops.mmap = relay_file_operations.mmap;
+ mmio_fops.release = relay_file_operations.release;
+ mmio_fops.splice_read = relay_file_operations.splice_read;
+
+ buf_file = debugfs_create_file(filename, mode, parent, buf,
+ &mmio_fops);
+
+ return buf_file;
+}
+
+/* file_remove() default callback. Removes relay file in debugfs. */
+static int remove_buf_file_handler(struct dentry *dentry)
+{
+ debugfs_remove(dentry);
+ return 0;
+}
+
+static struct rchan_callbacks relay_callbacks = {
+ .subbuf_start = subbuf_start_handler,
+ .create_buf_file = create_buf_file_handler,
+ .remove_buf_file = remove_buf_file_handler,
+};
+
+/*
+ * create_channel - creates channel /debug/APP_DIR/cpuXXX
+ * Returns channel on success, NULL otherwise
+ */
+static struct rchan *create_channel(unsigned size, unsigned n)
+{
+ return relay_open("cpu", dir, size, n, &relay_callbacks, NULL);
+}
+
+/* destroy_channel - destroys channel /debug/APP_DIR/cpuXXX */
+static void destroy_channel(void)
+{
+ if (chan) {
+ relay_close(chan);
+ chan = NULL;
+ }
+}
+
+struct remap_trace {
+ struct list_head list;
+ struct kmmio_probe probe;
+};
+static LIST_HEAD(trace_list);
+static DEFINE_SPINLOCK(trace_list_lock);
+
+static void do_ioremap_trace_core(unsigned long offset, unsigned long size,
+ void __iomem *addr)
+{
+ struct remap_trace *trace = kmalloc(sizeof(*trace), GFP_KERNEL);
+ struct mm_io_header_map event = {
+ .header = {
+ .type = MMIO_MAGIC |
+ (MMIO_PROBE << MMIO_OPCODE_SHIFT),
+ .sec = 0,
+ .nsec = 0,
+ .pid = 0,
+ .data_len = sizeof(struct mm_io_map)
+ },
+ .map = {
+ .phys = offset,
+ .addr = (unsigned long)addr,
+ .len = size,
+ .pc = 0
+ }
+ };
+ record_timestamp(&event.header);
+
+ *trace = (struct remap_trace) {
+ .probe = {
+ .addr = (unsigned long)addr,
+ .len = size,
+ .pre_handler = pre,
+ .post_handler = post,
+ }
+ };
+
+ relay_write(chan, &event, sizeof(event));
+ spin_lock(&trace_list_lock);
+ list_add_tail(&trace->list, &trace_list);
+ spin_unlock(&trace_list_lock);
+ if (!nommiotrace)
+ register_kmmio_probe(&trace->probe);
+}
+
+static void ioremap_trace_core(unsigned long offset, unsigned long size,
+ void __iomem *addr)
+{
+ if ((filter_offset) && (offset != filter_offset))
+ return;
+
+ /* Don't trace the low PCI/ISA area, it's always mapped.. */
+ if (!ISA_trace && (offset < ISA_END_ADDRESS) &&
+ (offset + size > ISA_START_ADDRESS)) {
+ printk(KERN_NOTICE MODULE_NAME ": Ignoring map of low "
+ "PCI/ISA area (0x%lx-0x%lx)\n",
+ offset, offset + size);
+ return;
+ }
+ do_ioremap_trace_core(offset, size, addr);
+}
+
+void __iomem *ioremap_cache_trace(unsigned long offset, unsigned long size)
+{
+ void __iomem *p = ioremap_cache(offset, size);
+ printk(KERN_DEBUG MODULE_NAME ": ioremap_cache(0x%lx, 0x%lx) = %p\n",
+ offset, size, p);
+ ioremap_trace_core(offset, size, p);
+ return p;
+}
+EXPORT_SYMBOL(ioremap_cache_trace);
+
+void __iomem *ioremap_nocache_trace(unsigned long offset, unsigned long size)
+{
+ void __iomem *p = ioremap_nocache(offset, size);
+ printk(KERN_DEBUG MODULE_NAME ": ioremap_nocache(0x%lx, 0x%lx) = %p\n",
+ offset, size, p);
+ ioremap_trace_core(offset, size, p);
+ return p;
+}
+EXPORT_SYMBOL(ioremap_nocache_trace);
+
+void iounmap_trace(volatile void __iomem *addr)
+{
+ struct mm_io_header_map event = {
+ .header = {
+ .type = MMIO_MAGIC |
+ (MMIO_UNPROBE << MMIO_OPCODE_SHIFT),
+ .sec = 0,
+ .nsec = 0,
+ .pid = 0,
+ .data_len = sizeof(struct mm_io_map)
+ },
+ .map = {
+ .phys = 0,
+ .addr = (unsigned long)addr,
+ .len = 0,
+ .pc = 0
+ }
+ };
+ struct remap_trace *trace;
+ struct remap_trace *tmp;
+ printk(KERN_DEBUG MODULE_NAME ": Unmapping %p.\n", addr);
+ record_timestamp(&event.header);
+
+ spin_lock(&trace_list_lock);
+ 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);
+ kfree(trace);
+ break;
+ }
+ }
+ spin_unlock(&trace_list_lock);
+ relay_write(chan, &event, sizeof(event));
+ iounmap(addr);
+}
+EXPORT_SYMBOL(iounmap_trace);
+
+static void clear_trace_list(void)
+{
+ struct remap_trace *trace;
+ struct remap_trace *tmp;
+
+ spin_lock(&trace_list_lock);
+ list_for_each_entry_safe(trace, tmp, &trace_list, list) {
+ printk(KERN_WARNING MODULE_NAME ": purging non-iounmapped "
+ "trace @0x%08lx, size 0x%lx.\n",
+ trace->probe.addr, trace->probe.len);
+ if (!nommiotrace)
+ unregister_kmmio_probe(&trace->probe);
+ list_del(&trace->list);
+ kfree(trace);
+ break;
+ }
+ spin_unlock(&trace_list_lock);
+}
+
+static int __init init(void)
+{
+ if (n_subbufs < 2)
+ return -EINVAL;
+
+ dir = debugfs_create_dir(APP_DIR, NULL);
+ if (!dir) {
+ printk(KERN_ERR MODULE_NAME
+ ": Couldn't create relay app directory.\n");
+ return -ENOMEM;
+ }
+
+ chan = create_channel(subbuf_size, n_subbufs);
+ if (!chan) {
+ debugfs_remove(dir);
+ printk(KERN_ERR MODULE_NAME
+ ": relay app channel creation failed\n");
+ return -ENOMEM;
+ }
+
+ init_kmmio();
+
+ proc_marker_file = create_proc_entry(MARKER_FILE, 0, NULL);
+ if (proc_marker_file)
+ proc_marker_file->write_proc = write_marker;
+
+ printk(KERN_DEBUG MODULE_NAME ": loaded.\n");
+ if (nommiotrace)
+ printk(KERN_DEBUG MODULE_NAME ": MMIO tracing disabled.\n");
+ if (ISA_trace)
+ printk(KERN_WARNING MODULE_NAME
+ ": Warning! low ISA range will be traced.\n");
+ return 0;
+}
+
+static void __exit cleanup(void)
+{
+ printk(KERN_DEBUG MODULE_NAME ": unload...\n");
+ clear_trace_list();
+ cleanup_kmmio();
+ remove_proc_entry(MARKER_FILE, NULL);
+ destroy_channel();
+ if (dir)
+ debugfs_remove(dir);
+}
+
+module_init(init);
+module_exit(cleanup);
+MODULE_LICENSE("GPL");
diff --git a/arch/x86/kernel/mmiotrace/pf_in.c b/arch/x86/kernel/mmiotrace/pf_in.c
new file mode 100644
index 00000000000..67ea520dde6
--- /dev/null
+++ b/arch/x86/kernel/mmiotrace/pf_in.c
@@ -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;
+}
diff --git a/arch/x86/kernel/mmiotrace/pf_in.h b/arch/x86/kernel/mmiotrace/pf_in.h
new file mode 100644
index 00000000000..e05341a51a2
--- /dev/null
+++ b/arch/x86/kernel/mmiotrace/pf_in.h
@@ -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_ */
diff --git a/arch/x86/kernel/mmiotrace/testmmiotrace.c b/arch/x86/kernel/mmiotrace/testmmiotrace.c
new file mode 100644
index 00000000000..40e66b0e648
--- /dev/null
+++ b/arch/x86/kernel/mmiotrace/testmmiotrace.c
@@ -0,0 +1,77 @@
+/*
+ * Written by Pekka Paalanen, 2008 <pq@iki.fi>
+ */
+#include <linux/module.h>
+#include <asm/io.h>
+
+extern void __iomem *ioremap_nocache_trace(unsigned long offset,
+ unsigned long size);
+extern void iounmap_trace(volatile void __iomem *addr);
+
+#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;
+ volatile unsigned int v;
+ for (i = 0; i < 256; i++)
+ v = ioread8(p + i);
+ for (i = 1024; i < (5 * 1024); i += 2)
+ v = ioread16(p + i);
+ for (i = (5 * 1024); i < (16 * 1024); i += 4)
+ v = ioread32(p + i);
+}
+
+static void do_test(void)
+{
+ void __iomem *p = ioremap_nocache_trace(mmio_address, 0x4000);
+ if (!p) {
+ printk(KERN_ERR MODULE_NAME ": could not ioremap IO memory, "
+ "aborting.\n");
+ return;
+ }
+ do_write_test(p);
+ do_read_test(p);
+ iounmap_trace(p);
+}
+
+static int __init init(void)
+{
+ if (mmio_address == 0) {
+ printk(KERN_ERR MODULE_NAME ": you have to use the module "
+ "argument mmio_address.\n");
+ printk(KERN_ERR MODULE_NAME ": DO NOT LOAD THIS MODULE UNLESS"
+ " YOU REALLY KNOW WHAT YOU ARE DOING!\n");
+ return -ENXIO;
+ }
+
+ printk(KERN_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)
+{
+ printk(KERN_DEBUG MODULE_NAME ": unloaded.\n");
+}
+
+module_init(init);
+module_exit(cleanup);
+MODULE_LICENSE("GPL");
diff --git a/include/linux/mmiotrace.h b/include/linux/mmiotrace.h
new file mode 100644
index 00000000000..cb247825f3e
--- /dev/null
+++ b/include/linux/mmiotrace.h
@@ -0,0 +1,62 @@
+#ifndef MMIOTRACE_H
+#define MMIOTRACE_H
+
+#include <asm/types.h>
+
+#define MMIO_VERSION 0x04
+
+/* mm_io_header.type */
+#define MMIO_OPCODE_MASK 0xff
+#define MMIO_OPCODE_SHIFT 0
+#define MMIO_WIDTH_MASK 0xff00
+#define MMIO_WIDTH_SHIFT 8
+#define MMIO_MAGIC (0x6f000000 | (MMIO_VERSION<<16))
+#define MMIO_MAGIC_MASK 0xffff0000
+
+enum mm_io_opcode { /* payload type: */
+ MMIO_READ = 0x1, /* struct mm_io_rw */
+ MMIO_WRITE = 0x2, /* struct mm_io_rw */
+ MMIO_PROBE = 0x3, /* struct mm_io_map */
+ MMIO_UNPROBE = 0x4, /* struct mm_io_map */
+ MMIO_MARKER = 0x5, /* raw char data */
+ MMIO_UNKNOWN_OP = 0x6, /* struct mm_io_rw */
+};
+
+struct mm_io_header {
+ __u32 type;
+ __u32 sec; /* timestamp */
+ __u32 nsec;
+ __u32 pid; /* PID of the process, or 0 for kernel core */
+ __u16 data_len; /* length of the following payload */
+};
+
+struct mm_io_rw {
+ __u64 address; /* virtual address of register */
+ __u64 value;
+ __u64 pc; /* optional program counter */
+};
+
+struct mm_io_map {
+ __u64 phys; /* base address in PCI space */
+ __u64 addr; /* base virtual address */
+ __u64 len; /* mapping size */
+ __u64 pc; /* optional program counter */
+};
+
+
+/*
+ * These structures are used to allow a single relay_write()
+ * call to write a full packet.
+ */
+
+struct mm_io_header_rw {
+ struct mm_io_header header;
+ struct mm_io_rw rw;
+} __attribute__((packed));
+
+struct mm_io_header_map {
+ struct mm_io_header header;
+ struct mm_io_map map;
+} __attribute__((packed));
+
+#endif /* MMIOTRACE_H */