diff options
| -rw-r--r-- | arch/x86/include/asm/iommu_table.h | 6 | ||||
| -rw-r--r-- | arch/x86/kernel/Makefile | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/pci-iommu_table.c | 89 |
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 435176f96a56..2124e3ef6f98 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 0925676266bd..6817546595ef 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 000000000000..55d745ec1181 --- /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 |