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This consolidates the bridge window enumeration logic into a single shared algorithm in the IOMMU core. Refactor iova_reserve_pci_windows() to use the new iterator, replacing its open-coded resource_list_for_each_entry loop. The callback receives phys_addr_t start/end directly, so the DMA path reserves the same ranges as before with zero intermediate allocation, and window lengths never pass through a size_t field (which would truncate on 32-bit PAE systems). Signed-off-by: Guanghui Feng --- drivers/iommu/dma-iommu.c | 22 ++++++++++++++-------- drivers/iommu/iommu-priv.h | 17 +++++++++++++++++ drivers/iommu/iommu.c | 37 +++++++++++++++++++++++++++++++++++++ 3 files changed, 68 insertions(+), 8 deletions(-) diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 78742aeba932..5b73e71c312e 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -505,6 +505,15 @@ static int iommu_dma_ranges_sort(void *priv, const struct list_head *a, return res_a->res->start > res_b->res->start; } +static int iova_reserve_pci_window_fn(phys_addr_t start, phys_addr_t end, + void *data) +{ + struct iova_domain *iovad = data; + + reserve_iova(iovad, iova_pfn(iovad, start), iova_pfn(iovad, end)); + return 0; +} + static int iova_reserve_pci_windows(struct pci_dev *dev, struct iova_domain *iovad) { @@ -512,15 +521,12 @@ static int iova_reserve_pci_windows(struct pci_dev *dev, struct resource_entry *window; unsigned long lo, hi; phys_addr_t start = 0, end; + int ret; - resource_list_for_each_entry(window, &bridge->windows) { - if (resource_type(window->res) != IORESOURCE_MEM) - continue; - - lo = iova_pfn(iovad, window->res->start - window->offset); - hi = iova_pfn(iovad, window->res->end - window->offset); - reserve_iova(iovad, lo, hi); - } + ret = iommu_for_each_pci_mmio_window(dev, iova_reserve_pci_window_fn, + iovad); + if (ret) + return ret; /* Get reserved DMA windows from host bridge */ list_sort(NULL, &bridge->dma_ranges, iommu_dma_ranges_sort); diff --git a/drivers/iommu/iommu-priv.h b/drivers/iommu/iommu-priv.h index 1f9f886b2c10..81c5b5ce67ec 100644 --- a/drivers/iommu/iommu-priv.h +++ b/drivers/iommu/iommu-priv.h @@ -127,4 +127,21 @@ static inline void iommu_debug_init(void) #endif /* CONFIG_IOMMU_DEBUG_PAGEALLOC */ +struct pci_dev; + +typedef int (*iommu_pci_mmio_window_fn_t)(phys_addr_t start, phys_addr_t end, + void *data); + +#ifdef CONFIG_PCI +int iommu_for_each_pci_mmio_window(struct pci_dev *dev, + iommu_pci_mmio_window_fn_t fn, void *data); +#else +static inline int iommu_for_each_pci_mmio_window(struct pci_dev *dev, + iommu_pci_mmio_window_fn_t fn, + void *data) +{ + return 0; +} +#endif /* CONFIG_PCI */ + #endif /* __LINUX_IOMMU_PRIV_H */ diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index b486b8bbd1fc..6b0e2b08ceba 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -945,6 +945,43 @@ iommu_insert_device_resv_regions(struct list_head *dev_resv_regions, return ret; } +#ifdef CONFIG_PCI +/** + * iommu_for_each_pci_mmio_window - iterate over PCI host bridge MMIO windows + * @dev: PCI device whose host bridge to scan + * @fn: callback invoked with each window's bus address range (inclusive) + * @data: opaque pointer passed to @fn + * + * Iteration stops early if @fn returns non-zero, and that value is + * propagated to the caller. + * + * Return: 0 on success, negative errno on failure (including from @fn). + */ +int iommu_for_each_pci_mmio_window(struct pci_dev *dev, + iommu_pci_mmio_window_fn_t fn, void *data) +{ + struct pci_host_bridge *bridge = pci_find_host_bridge(dev->bus); + struct resource_entry *window; + + if (WARN_ON(!bridge)) + return -ENODEV; + + resource_list_for_each_entry(window, &bridge->windows) { + int ret; + + if (resource_type(window->res) != IORESOURCE_MEM) + continue; + + ret = fn(window->res->start - window->offset, + window->res->end - window->offset, data); + if (ret) + return ret; + } + return 0; +} +EXPORT_SYMBOL_GPL(iommu_for_each_pci_mmio_window); +#endif /* CONFIG_PCI */ + int iommu_get_group_resv_regions(struct iommu_group *group, struct list_head *head) { -- 2.43.7