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-rw-r--r--arch/x86/include/asm/iommu_table.h6
-rw-r--r--arch/x86/kernel/Makefile1
-rw-r--r--arch/x86/kernel/pci-iommu_table.c89
3 files changed, 96 insertions, 0 deletions
diff --git a/arch/x86/include/asm/iommu_table.h b/arch/x86/include/asm/iommu_table.h
index 435176f96a5..2124e3ef6f9 100644
--- a/arch/x86/include/asm/iommu_table.h
+++ b/arch/x86/include/asm/iommu_table.h
@@ -92,4 +92,10 @@ struct iommu_table_entry {
#define IOMMU_INIT(_detect, _depend, _init, _late_init) \
__IOMMU_INIT(_detect, _depend, _init, _late_init, 0)
+void sort_iommu_table(struct iommu_table_entry *start,
+ struct iommu_table_entry *finish);
+
+void check_iommu_entries(struct iommu_table_entry *start,
+ struct iommu_table_entry *finish);
+
#endif /* _ASM_X86_IOMMU_TABLE_H */
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 0925676266b..6817546595e 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -42,6 +42,7 @@ obj-y += bootflag.o e820.o
obj-y += pci-dma.o quirks.o i8237.o topology.o kdebugfs.o
obj-y += alternative.o i8253.o pci-nommu.o hw_breakpoint.o
obj-y += tsc.o io_delay.o rtc.o
+obj-y += pci-iommu_table.o
obj-$(CONFIG_X86_TRAMPOLINE) += trampoline.o
obj-y += process.o
diff --git a/arch/x86/kernel/pci-iommu_table.c b/arch/x86/kernel/pci-iommu_table.c
new file mode 100644
index 00000000000..55d745ec118
--- /dev/null
+++ b/arch/x86/kernel/pci-iommu_table.c
@@ -0,0 +1,89 @@
+#include <linux/dma-mapping.h>
+#include <asm/iommu_table.h>
+#include <linux/string.h>
+#include <linux/kallsyms.h>
+
+
+#define DEBUG 1
+
+static struct iommu_table_entry * __init
+find_dependents_of(struct iommu_table_entry *start,
+ struct iommu_table_entry *finish,
+ struct iommu_table_entry *q)
+{
+ struct iommu_table_entry *p;
+
+ if (!q)
+ return NULL;
+
+ for (p = start; p < finish; p++)
+ if (p->detect == q->depend)
+ return p;
+
+ return NULL;
+}
+
+
+void __init sort_iommu_table(struct iommu_table_entry *start,
+ struct iommu_table_entry *finish) {
+
+ struct iommu_table_entry *p, *q, tmp;
+
+ for (p = start; p < finish; p++) {
+again:
+ q = find_dependents_of(start, finish, p);
+ /* We are bit sneaky here. We use the memory address to figure
+ * out if the node we depend on is past our point, if so, swap.
+ */
+ if (q > p) {
+ tmp = *p;
+ memmove(p, q, sizeof(*p));
+ *q = tmp;
+ goto again;
+ }
+ }
+
+}
+
+#ifdef DEBUG
+void __init check_iommu_entries(struct iommu_table_entry *start,
+ struct iommu_table_entry *finish)
+{
+ struct iommu_table_entry *p, *q, *x;
+ char sym_p[KSYM_SYMBOL_LEN];
+ char sym_q[KSYM_SYMBOL_LEN];
+
+ /* Simple cyclic dependency checker. */
+ for (p = start; p < finish; p++) {
+ q = find_dependents_of(start, finish, p);
+ x = find_dependents_of(start, finish, q);
+ if (p == x) {
+ sprint_symbol(sym_p, (unsigned long)p->detect);
+ sprint_symbol(sym_q, (unsigned long)q->detect);
+
+ printk(KERN_ERR "CYCLIC DEPENDENCY FOUND! %s depends" \
+ " on %s and vice-versa. BREAKING IT.\n",
+ sym_p, sym_q);
+ /* Heavy handed way..*/
+ x->depend = 0;
+ }
+ }
+
+ for (p = start; p < finish; p++) {
+ q = find_dependents_of(p, finish, p);
+ if (q && q > p) {
+ sprint_symbol(sym_p, (unsigned long)p->detect);
+ sprint_symbol(sym_q, (unsigned long)q->detect);
+
+ printk(KERN_ERR "EXECUTION ORDER INVALID! %s "\
+ "should be called before %s!\n",
+ sym_p, sym_q);
+ }
+ }
+}
+#else
+inline void check_iommu_entries(struct iommu_table_entry *start,
+ struct iommu_table_entry *finish)
+{
+}
+#endif