diff options
| -rw-r--r-- | arch/x86_64/kernel/pci-calgary.c | 44 |
1 files changed, 35 insertions, 9 deletions
diff --git a/arch/x86_64/kernel/pci-calgary.c b/arch/x86_64/kernel/pci-calgary.c index ebe4e930b64d..7c43cb0f71a3 100644 --- a/arch/x86_64/kernel/pci-calgary.c +++ b/arch/x86_64/kernel/pci-calgary.c @@ -133,12 +133,35 @@ static inline void tce_cache_blast_stress(struct iommu_table *tbl) { tce_cache_blast(tbl); } + +static inline unsigned long verify_bit_range(unsigned long* bitmap, + int expected, unsigned long start, unsigned long end) +{ + unsigned long idx = start; + + BUG_ON(start >= end); + + while (idx < end) { + if (!!test_bit(idx, bitmap) != expected) + return idx; + ++idx; + } + + /* all bits have the expected value */ + return ~0UL; +} #else /* debugging is disabled */ int debugging __read_mostly = 0; static inline void tce_cache_blast_stress(struct iommu_table *tbl) { } + +static inline unsigned long verify_bit_range(unsigned long* bitmap, + int expected, unsigned long start, unsigned long end) +{ + return ~0UL; +} #endif /* CONFIG_IOMMU_DEBUG */ static inline unsigned int num_dma_pages(unsigned long dma, unsigned int dmalen) @@ -162,6 +185,7 @@ static void iommu_range_reserve(struct iommu_table *tbl, { unsigned long index; unsigned long end; + unsigned long badbit; index = start_addr >> PAGE_SHIFT; @@ -173,14 +197,15 @@ static void iommu_range_reserve(struct iommu_table *tbl, if (end > tbl->it_size) /* don't go off the table */ end = tbl->it_size; - while (index < end) { - if (test_bit(index, tbl->it_map)) + badbit = verify_bit_range(tbl->it_map, 0, index, end); + if (badbit != ~0UL) { + if (printk_ratelimit()) printk(KERN_ERR "Calgary: entry already allocated at " "0x%lx tbl %p dma 0x%lx npages %u\n", - index, tbl, start_addr, npages); - ++index; + badbit, tbl, start_addr, npages); } - set_bit_string(tbl->it_map, start_addr >> PAGE_SHIFT, npages); + + set_bit_string(tbl->it_map, index, npages); } static unsigned long iommu_range_alloc(struct iommu_table *tbl, @@ -247,7 +272,7 @@ static void __iommu_free(struct iommu_table *tbl, dma_addr_t dma_addr, unsigned int npages) { unsigned long entry; - unsigned long i; + unsigned long badbit; entry = dma_addr >> PAGE_SHIFT; @@ -255,11 +280,12 @@ static void __iommu_free(struct iommu_table *tbl, dma_addr_t dma_addr, tce_free(tbl, entry, npages); - for (i = 0; i < npages; ++i) { - if (!test_bit(entry + i, tbl->it_map)) + badbit = verify_bit_range(tbl->it_map, 1, entry, entry + npages); + if (badbit != ~0UL) { + if (printk_ratelimit()) printk(KERN_ERR "Calgary: bit is off at 0x%lx " "tbl %p dma 0x%Lx entry 0x%lx npages %u\n", - entry + i, tbl, dma_addr, entry, npages); + badbit, tbl, dma_addr, entry, npages); } __clear_bit_string(tbl->it_map, entry, npages); |