Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753488AbYLSRkO (ORCPT ); Fri, 19 Dec 2008 12:40:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752154AbYLSRkB (ORCPT ); Fri, 19 Dec 2008 12:40:01 -0500 Received: from gw.goop.org ([64.81.55.164]:34439 "EHLO mail.goop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752130AbYLSRkA (ORCPT ); Fri, 19 Dec 2008 12:40:00 -0500 Message-ID: <494BDC6E.8050509@goop.org> Date: Fri, 19 Dec 2008 09:39:58 -0800 From: Jeremy Fitzhardinge User-Agent: Thunderbird 2.0.0.18 (X11/20081119) MIME-Version: 1.0 To: Becky Bruce CC: mingo@elte.hu, fujita.tomonori@lab.ntt.co.jp, linux-kernel@vger.kernel.org, ian.campbell@citrix.com, jbeulich@novell.com, joerg.roedel@amd.com, benh@kernel.crashing.org Subject: Re: [PATCH 06/11] swiotlb: Store phys address in io_tlb_orig_addr array References: <20081218210231.GB24271@elte.hu> <1229663480-10757-7-git-send-email-beckyb@kernel.crashing.org> In-Reply-To: <1229663480-10757-7-git-send-email-beckyb@kernel.crashing.org> X-Enigmail-Version: 0.95.6 Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6880 Lines: 183 Becky Bruce wrote: > When we enable swiotlb for platforms that support HIGHMEM, we > can no longer store the virtual address of the original dma > buffer, because that buffer might not have a permament mapping. > Change the iotlb code to instead store the physical address of > the original buffer. > Hm, yes, I think using a phys_addr_t may end up being cleaner than using struct page *+offset. J > Signed-off-by: Becky Bruce > --- > lib/swiotlb.c | 47 ++++++++++++++++++++++++----------------------- > 1 files changed, 24 insertions(+), 23 deletions(-) > > diff --git a/lib/swiotlb.c b/lib/swiotlb.c > index ed4f44a..e9d5bf6 100644 > --- a/lib/swiotlb.c > +++ b/lib/swiotlb.c > @@ -118,7 +118,7 @@ static unsigned int io_tlb_index; > * We need to save away the original address corresponding to a mapped entry > * for the sync operations. > */ > -static unsigned char **io_tlb_orig_addr; > +static phys_addr_t *io_tlb_orig_addr; > > /* > * Protect the above data structures in the map and unmap calls > @@ -175,7 +175,7 @@ swiotlb_init_with_default_size(size_t default_size) > for (i = 0; i < io_tlb_nslabs; i++) > io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE); > io_tlb_index = 0; > - io_tlb_orig_addr = alloc_bootmem(io_tlb_nslabs * sizeof(char *)); > + io_tlb_orig_addr = alloc_bootmem(io_tlb_nslabs * sizeof(phys_addr_t)); > > /* > * Get the overflow emergency buffer > @@ -253,12 +253,14 @@ swiotlb_late_init_with_default_size(size_t default_size) > io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE); > io_tlb_index = 0; > > - io_tlb_orig_addr = (unsigned char **)__get_free_pages(GFP_KERNEL, > - get_order(io_tlb_nslabs * sizeof(char *))); > + io_tlb_orig_addr = (phys_addr_t *) > + __get_free_pages(GFP_KERNEL, > + get_order(io_tlb_nslabs * > + sizeof(phys_addr_t))); > if (!io_tlb_orig_addr) > goto cleanup3; > > - memset(io_tlb_orig_addr, 0, io_tlb_nslabs * sizeof(char *)); > + memset(io_tlb_orig_addr, 0, io_tlb_nslabs * sizeof(phys_addr_t)); > > /* > * Get the overflow emergency buffer > @@ -276,8 +278,8 @@ swiotlb_late_init_with_default_size(size_t default_size) > return 0; > > cleanup4: > - free_pages((unsigned long)io_tlb_orig_addr, get_order(io_tlb_nslabs * > - sizeof(char *))); > + 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 * > @@ -307,7 +309,7 @@ static int is_swiotlb_buffer(char *addr) > * Allocates bounce buffer and returns its kernel virtual address. > */ > static void * > -map_single(struct device *hwdev, char *buffer, size_t size, int dir) > +map_single(struct device *hwdev, phys_addr_t phys, size_t size, int dir) > { > unsigned long flags; > char *dma_addr; > @@ -398,9 +400,9 @@ found: > * needed. > */ > for (i = 0; i < nslots; i++) > - io_tlb_orig_addr[index+i] = buffer + (i << IO_TLB_SHIFT); > + io_tlb_orig_addr[index+i] = phys + (i << IO_TLB_SHIFT); > if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL) > - memcpy(dma_addr, buffer, size); > + memcpy(dma_addr, phys_to_virt(phys), size); > > return dma_addr; > } > @@ -414,17 +416,17 @@ unmap_single(struct device *hwdev, char *dma_addr, size_t size, int dir) > unsigned long flags; > int i, count, nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; > int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT; > - char *buffer = io_tlb_orig_addr[index]; > + phys_addr_t phys = io_tlb_orig_addr[index]; > > /* > * First, sync the memory before unmapping the entry > */ > - if (buffer && ((dir == DMA_FROM_DEVICE) || (dir == DMA_BIDIRECTIONAL))) > + if (phys && ((dir == DMA_FROM_DEVICE) || (dir == DMA_BIDIRECTIONAL))) > /* > * bounce... copy the data back into the original buffer * and > * delete the bounce buffer. > */ > - memcpy(buffer, dma_addr, size); > + memcpy(phys_to_virt(phys), dma_addr, size); > > /* > * Return the buffer to the free list by setting the corresponding > @@ -457,20 +459,20 @@ sync_single(struct device *hwdev, char *dma_addr, size_t size, > int dir, int target) > { > int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT; > - char *buffer = io_tlb_orig_addr[index]; > + phys_addr_t phys = io_tlb_orig_addr[index]; > > - buffer += ((unsigned long)dma_addr & ((1 << IO_TLB_SHIFT) - 1)); > + phys += ((unsigned long)dma_addr & ((1 << IO_TLB_SHIFT) - 1)); > > switch (target) { > case SYNC_FOR_CPU: > if (likely(dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)) > - memcpy(buffer, dma_addr, size); > + memcpy(phys_to_virt(phys), dma_addr, size); > else > BUG_ON(dir != DMA_TO_DEVICE); > break; > case SYNC_FOR_DEVICE: > if (likely(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)) > - memcpy(dma_addr, buffer, size); > + memcpy(dma_addr, phys_to_virt(phys), size); > else > BUG_ON(dir != DMA_FROM_DEVICE); > break; > @@ -509,7 +511,7 @@ swiotlb_alloc_coherent(struct device *hwdev, size_t size, > * swiotlb_map_single(), which will grab memory from > * the lowest available address range. > */ > - ret = map_single(hwdev, NULL, size, DMA_FROM_DEVICE); > + ret = map_single(hwdev, 0, size, DMA_FROM_DEVICE); > if (!ret) > return NULL; > } > @@ -591,7 +593,7 @@ swiotlb_map_single_attrs(struct device *hwdev, void *ptr, size_t size, > /* > * Oh well, have to allocate and map a bounce buffer. > */ > - map = map_single(hwdev, ptr, size, dir); > + map = map_single(hwdev, virt_to_phys(ptr), size, dir); > if (!map) { > swiotlb_full(hwdev, size, dir, 1); > map = io_tlb_overflow_buffer; > @@ -736,18 +738,17 @@ swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems, > int dir, struct dma_attrs *attrs) > { > struct scatterlist *sg; > - void *addr; > dma_addr_t dev_addr; > int i; > > BUG_ON(dir == DMA_NONE); > > for_each_sg(sgl, sg, nelems, i) { > - addr = sg_virt(sg); > - dev_addr = virt_to_dma_addr(hwdev, addr); > + dev_addr = SG_ENT_BUS_ADDRESS(hwdev, sg); > if (swiotlb_force || > swiotlb_addr_needs_mapping(hwdev, dev_addr, sg->length)) { > - void *map = map_single(hwdev, addr, sg->length, dir); > + void *map = map_single(hwdev, sg_phys(sg), sg->length, > + dir); > if (!map) { > /* Don't panic here, we expect map_sg users > to do proper error handling. */ > -- 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/