[PATCH v1 2/2] powerpc/mmiotrace: bind ioremap and page fault to active mmiotrace

[Jialong Yang]

Hacking the code in ioremap entry and page fault handler entry to
integrate mmiotrace.

Signed-off-by: Jialong Yang <jialong.y...@shingroup.cn>
---
 arch/powerpc/mm/fault.c      | 17 +++++++++++++++++
 arch/powerpc/mm/ioremap_64.c | 11 +++++++++--
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c
index 215690452495..b03cba73de92 100644
--- a/arch/powerpc/mm/fault.c
+++ b/arch/powerpc/mm/fault.c
@@ -22,6 +22,7 @@
 #include <linux/ptrace.h>
 #include <linux/mman.h>
 #include <linux/mm.h>
+#include <linux/mmiotrace.h>
 #include <linux/interrupt.h>
 #include <linux/highmem.h>
 #include <linux/extable.h>
@@ -50,6 +51,19 @@
  * do_page_fault error handling helpers
  */
 
+/*
+ * Returns 0 if mmiotrace is disabled, or if the fault is not
+ * handled by mmiotrace:
+ */
+static nokprobe_inline int
+kmmio_fault(struct pt_regs *regs, unsigned long addr)
+{
+       if (unlikely(is_kmmio_active()))
+               if (kmmio_handler(regs, addr) == 1)
+                       return -1;
+       return 0;
+}
+
 static int
 __bad_area_nosemaphore(struct pt_regs *regs, unsigned long address, int 
si_code)
 {
@@ -422,6 +436,9 @@ static int ___do_page_fault(struct pt_regs *regs, unsigned 
long address,
        vm_fault_t fault, major = 0;
        bool kprobe_fault = kprobe_page_fault(regs, 11);
 
+       if (unlikely(kmmio_fault(regs, address)))
+               return 0;
+
        if (unlikely(debugger_fault_handler(regs) || kprobe_fault))
                return 0;
 
diff --git a/arch/powerpc/mm/ioremap_64.c b/arch/powerpc/mm/ioremap_64.c
index d24e5f166723..f5f717bf35df 100644
--- a/arch/powerpc/mm/ioremap_64.c
+++ b/arch/powerpc/mm/ioremap_64.c
@@ -3,12 +3,15 @@
 #include <linux/io.h>
 #include <linux/slab.h>
 #include <linux/vmalloc.h>
+#include <linux/mmiotrace.h>
 
 void __iomem *__ioremap_caller(phys_addr_t addr, unsigned long size,
                               pgprot_t prot, void *caller)
 {
        phys_addr_t paligned, offset;
        void __iomem *ret;
+       phys_addr_t unaligned_phys_addr = addr;
+       const unsigned long unaligned_size = size;
        int err;
 
        /* We don't support the 4K PFN hack with ioremap */
@@ -28,8 +31,11 @@ void __iomem *__ioremap_caller(phys_addr_t addr, unsigned 
long size,
        if (size == 0 || paligned == 0)
                return NULL;
 
-       if (slab_is_available())
-               return generic_ioremap_prot(addr, size, prot);
+       if (slab_is_available()) {
+               ret = generic_ioremap_prot(addr, size, prot);
+               mmiotrace_ioremap(unaligned_phys_addr, unaligned_size, ret);
+               return ret;
+       }
 
        pr_warn("ioremap() called early from %pS. Use early_ioremap() 
instead\n", caller);
 
@@ -52,6 +58,7 @@ void iounmap(volatile void __iomem *token)
        if (!slab_is_available())
                return;
 
+       mmiotrace_iounmap(token);
        generic_iounmap(PCI_FIX_ADDR(token));
 }
 EXPORT_SYMBOL(iounmap);
-- 
2.34.1