Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755577Ab2JFAeD (ORCPT ); Fri, 5 Oct 2012 20:34:03 -0400 Received: from mga03.intel.com ([143.182.124.21]:64179 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754343Ab2JFAdr (ORCPT ); Fri, 5 Oct 2012 20:33:47 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.80,541,1344236400"; d="scan'208";a="153038989" From: Alexander Duyck Subject: [PATCH 3/7] swiotlb: Make io_tlb_overflow_buffer a physical address To: konrad.wilk@oracle.com, tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, rob@landley.net, akpm@linux-foundation.org, joerg.roedel@amd.com, bhelgaas@google.com, shuahkhan@gmail.com, fujita.tomonori@lab.ntt.co.jp Cc: linux-kernel@vger.kernel.org, x86@kernel.org Date: Fri, 05 Oct 2012 17:34:05 -0700 Message-ID: <20121006003405.2561.54365.stgit@gitlad.jf.intel.com> In-Reply-To: <20121006000746.2561.67407.stgit@gitlad.jf.intel.com> References: <20121006000746.2561.67407.stgit@gitlad.jf.intel.com> User-Agent: StGIT/0.14.2 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6341 Lines: 189 This change makes it so that we can avoid virt_to_phys overhead when using the io_tlb_overflow_buffer. My original plan was to completely remove the value and replace it with a constant but I had seen that there were recent patches that stated this couldn't be done until all device drivers that depended on that functionality be updated. Signed-off-by: Alexander Duyck --- lib/swiotlb.c | 61 ++++++++++++++++++++++++++++++++------------------------- 1 files changed, 34 insertions(+), 27 deletions(-) diff --git a/lib/swiotlb.c b/lib/swiotlb.c index 3c45f10..bbf36d1 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -70,7 +70,7 @@ static unsigned long io_tlb_nslabs; */ static unsigned long io_tlb_overflow = 32*1024; -static void *io_tlb_overflow_buffer; +phys_addr_t io_tlb_overflow_buffer; /* * This is a free list describing the number of free entries available from @@ -138,6 +138,7 @@ void swiotlb_print_info(void) void __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) { + void *v_overflow_buffer; unsigned long i, bytes; bytes = nslabs << IO_TLB_SHIFT; @@ -146,6 +147,15 @@ void __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) io_tlb_addr = __pa(tlb); /* + * Get the overflow emergency buffer + */ + v_overflow_buffer = alloc_bootmem_low_pages(PAGE_ALIGN(io_tlb_overflow)); + if (!v_overflow_buffer) + panic("Cannot allocate SWIOTLB overflow buffer!\n"); + + io_tlb_overflow_buffer = __pa(v_overflow_buffer); + + /* * Allocate and initialize the free list array. This array is used * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE */ @@ -155,12 +165,6 @@ void __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) io_tlb_index = 0; io_tlb_orig_addr = alloc_bootmem_pages(PAGE_ALIGN(io_tlb_nslabs * sizeof(phys_addr_t))); - /* - * Get the overflow emergency buffer - */ - io_tlb_overflow_buffer = alloc_bootmem_low_pages(PAGE_ALIGN(io_tlb_overflow)); - if (!io_tlb_overflow_buffer) - panic("Cannot allocate SWIOTLB overflow buffer!\n"); if (verbose) swiotlb_print_info(); } @@ -250,6 +254,7 @@ int swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) { unsigned long i, bytes; + unsigned char *v_overflow_buffer; bytes = nslabs << IO_TLB_SHIFT; @@ -259,13 +264,23 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) memset(tlb, 0, bytes); /* + * Get the overflow emergency buffer + */ + v_overflow_buffer = (void *)__get_free_pages(GFP_DMA, + get_order(io_tlb_overflow)); + if (!v_overflow_buffer) + goto cleanup2; + + io_tlb_overflow_buffer = virt_to_phys(v_overflow_buffer); + + /* * Allocate and initialize the free list array. This array is used * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE */ io_tlb_list = (unsigned int *)__get_free_pages(GFP_KERNEL, get_order(io_tlb_nslabs * sizeof(int))); if (!io_tlb_list) - goto cleanup2; + goto cleanup3; for (i = 0; i < io_tlb_nslabs; i++) io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE); @@ -276,18 +291,10 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) get_order(io_tlb_nslabs * sizeof(phys_addr_t))); if (!io_tlb_orig_addr) - goto cleanup3; + goto cleanup4; memset(io_tlb_orig_addr, 0, io_tlb_nslabs * sizeof(phys_addr_t)); - /* - * Get the overflow emergency buffer - */ - io_tlb_overflow_buffer = (void *)__get_free_pages(GFP_DMA, - get_order(io_tlb_overflow)); - if (!io_tlb_overflow_buffer) - goto cleanup4; - swiotlb_print_info(); late_alloc = 1; @@ -295,13 +302,13 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) return 0; cleanup4: - free_pages((unsigned long)io_tlb_orig_addr, - get_order(io_tlb_nslabs * sizeof(phys_addr_t))); - io_tlb_orig_addr = NULL; -cleanup3: free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs * sizeof(int))); io_tlb_list = NULL; +cleanup3: + free_pages((unsigned long)v_overflow_buffer, + get_order(io_tlb_overflow)); + io_tlb_overflow_buffer = 0; cleanup2: io_tlb_addr = 0; io_tlb_nslabs = 0; @@ -310,11 +317,11 @@ cleanup2: void __init swiotlb_free(void) { - if (!io_tlb_overflow_buffer) + if (!io_tlb_orig_addr) return; if (late_alloc) { - free_pages((unsigned long)io_tlb_overflow_buffer, + free_pages((unsigned long)phys_to_virt(io_tlb_overflow_buffer), get_order(io_tlb_overflow)); free_pages((unsigned long)io_tlb_orig_addr, get_order(io_tlb_nslabs * sizeof(phys_addr_t))); @@ -323,7 +330,7 @@ void __init swiotlb_free(void) free_pages((unsigned long)phys_to_virt(io_tlb_addr), get_order(io_tlb_nslabs << IO_TLB_SHIFT)); } else { - free_bootmem_late(__pa(io_tlb_overflow_buffer), + free_bootmem_late(io_tlb_overflow_buffer, PAGE_ALIGN(io_tlb_overflow)); free_bootmem_late(__pa(io_tlb_orig_addr), PAGE_ALIGN(io_tlb_nslabs * sizeof(phys_addr_t))); @@ -694,7 +701,7 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page, map = map_single(dev, phys, size, dir); if (!map) { swiotlb_full(dev, size, dir, 1); - map = io_tlb_overflow_buffer; + return phys_to_dma(dev, io_tlb_overflow_buffer); } dev_addr = swiotlb_virt_to_bus(dev, map); @@ -704,7 +711,7 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page, */ if (!dma_capable(dev, dev_addr, size)) { swiotlb_tbl_unmap_single(dev, map, size, dir); - dev_addr = swiotlb_virt_to_bus(dev, io_tlb_overflow_buffer); + return phys_to_dma(dev, io_tlb_overflow_buffer); } return dev_addr; @@ -923,7 +930,7 @@ EXPORT_SYMBOL(swiotlb_sync_sg_for_device); int swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr) { - return (dma_addr == swiotlb_virt_to_bus(hwdev, io_tlb_overflow_buffer)); + return (dma_addr == phys_to_dma(hwdev, io_tlb_overflow_buffer)); } EXPORT_SYMBOL(swiotlb_dma_mapping_error); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/