diff --git a/drivers/pci/endpoint/pci-epc-mem.c b/drivers/pci/endpoint/pci-epc-mem.c index 83b7d5d3fc3e..60fbfe92e0ef 100644 --- a/drivers/pci/endpoint/pci-epc-mem.c +++ b/drivers/pci/endpoint/pci-epc-mem.c @@ -90,6 +90,7 @@ int __pci_epc_mem_init(struct pci_epc *epc, phys_addr_t phys_base, size_t size, mem->page_size = page_size; mem->pages = pages; mem->size = size; + mutex_init(&mem->lock); epc->mem = mem; @@ -133,7 +134,7 @@ void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc, phys_addr_t *phys_addr, size_t size) { int pageno; - void __iomem *virt_addr; + void __iomem *virt_addr = NULL; struct pci_epc_mem *mem = epc->mem; unsigned int page_shift = ilog2(mem->page_size); int order; @@ -141,15 +142,18 @@ void __iomem *pci_epc_mem_alloc_addr(struct pci_epc *epc, size = ALIGN(size, mem->page_size); order = pci_epc_mem_get_order(mem, size); + mutex_lock(&mem->lock); pageno = bitmap_find_free_region(mem->bitmap, mem->pages, order); if (pageno < 0) - return NULL; + goto ret; *phys_addr = mem->phys_base + (pageno << page_shift); virt_addr = ioremap(*phys_addr, size); if (!virt_addr) bitmap_release_region(mem->bitmap, pageno, order); +ret: + mutex_unlock(&mem->lock); return virt_addr; } EXPORT_SYMBOL_GPL(pci_epc_mem_alloc_addr); @@ -175,7 +179,9 @@ void pci_epc_mem_free_addr(struct pci_epc *epc, phys_addr_t phys_addr, pageno = (phys_addr - mem->phys_base) >> page_shift; size = ALIGN(size, mem->page_size); order = pci_epc_mem_get_order(mem, size); + mutex_lock(&mem->lock); bitmap_release_region(mem->bitmap, pageno, order); + mutex_unlock(&mem->lock); } EXPORT_SYMBOL_GPL(pci_epc_mem_free_addr); diff --git a/include/linux/pci-epc.h b/include/linux/pci-epc.h index f7a04e1af112..abbc74621f38 100644 --- a/include/linux/pci-epc.h +++ b/include/linux/pci-epc.h @@ -63,6 +63,7 @@ struct pci_epc_ops { * @bitmap: bitmap to manage the PCI address space * @pages: number of bits representing the address region * @page_size: size of each page + * @lock: mutex to protect bitmap */ struct pci_epc_mem { phys_addr_t phys_base; @@ -70,6 +71,8 @@ struct pci_epc_mem { unsigned long *bitmap; size_t page_size; int pages; + /* mutex to protect against concurrent access for memory allocation*/ + struct mutex lock; }; /**