From ceb5ac3264686e75e6951de6a18d4baa9bdecb92 Mon Sep 17 00:00:00 2001 From: Becky Bruce Date: Wed, 8 Apr 2009 09:09:15 -0500 Subject: swiotlb: comment corrections Impact: cleanup swiotlb_map/unmap_single are now swiotlb_map/unmap_page; trivially change all the comments to reference new names. Also, there were some comments that should have been referring to just plain old map_single, not swiotlb_map_single; fix those as well. Also change a use of the word "pointer", when what is referred to is actually a dma/physical address. Signed-off-by: Becky Bruce Acked-by: FUJITA Tomonori Signed-off-by: Kumar Gala Cc: jeremy@goop.org Cc: ian.campbell@citrix.com LKML-Reference: <1239199761-22886-2-git-send-email-galak@kernel.crashing.org> Signed-off-by: Ingo Molnar --- lib/swiotlb.c | 24 +++++++++++------------- 1 file changed, 11 insertions(+), 13 deletions(-) (limited to 'lib/swiotlb.c') diff --git a/lib/swiotlb.c b/lib/swiotlb.c index 2b0b5a7d2ce..170cf56af6a 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -60,8 +60,8 @@ enum dma_sync_target { int swiotlb_force; /* - * Used to do a quick range check in swiotlb_unmap_single and - * swiotlb_sync_single_*, to see if the memory was in fact allocated by this + * Used to do a quick range check in unmap_single and + * sync_single_*, to see if the memory was in fact allocated by this * API. */ static char *io_tlb_start, *io_tlb_end; @@ -560,7 +560,6 @@ swiotlb_alloc_coherent(struct device *hwdev, size_t size, size)) { /* * The allocated memory isn't reachable by the device. - * Fall back on swiotlb_map_single(). */ free_pages((unsigned long) ret, order); ret = NULL; @@ -568,9 +567,8 @@ swiotlb_alloc_coherent(struct device *hwdev, size_t size, if (!ret) { /* * We are either out of memory or the device can't DMA - * to GFP_DMA memory; fall back on - * swiotlb_map_single(), which will grab memory from - * the lowest available address range. + * to GFP_DMA memory; fall back on map_single(), which + * will grab memory from the lowest available address range. */ ret = map_single(hwdev, 0, size, DMA_FROM_DEVICE); if (!ret) @@ -634,7 +632,7 @@ swiotlb_full(struct device *dev, size_t size, int dir, int do_panic) * physical address to use is returned. * * Once the device is given the dma address, the device owns this memory until - * either swiotlb_unmap_single or swiotlb_dma_sync_single is performed. + * either swiotlb_unmap_page or swiotlb_dma_sync_single is performed. */ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page, unsigned long offset, size_t size, @@ -648,7 +646,7 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page, BUG_ON(dir == DMA_NONE); /* - * If the pointer passed in happens to be in the device's DMA window, + * If the address happens to be in the device's DMA window, * we can safely return the device addr and not worry about bounce * buffering it. */ @@ -679,7 +677,7 @@ EXPORT_SYMBOL_GPL(swiotlb_map_page); /* * Unmap a single streaming mode DMA translation. The dma_addr and size must - * match what was provided for in a previous swiotlb_map_single call. All + * match what was provided for in a previous swiotlb_map_page call. All * other usages are undefined. * * After this call, reads by the cpu to the buffer are guaranteed to see @@ -703,7 +701,7 @@ EXPORT_SYMBOL_GPL(swiotlb_unmap_page); * Make physical memory consistent for a single streaming mode DMA translation * after a transfer. * - * If you perform a swiotlb_map_single() but wish to interrogate the buffer + * If you perform a swiotlb_map_page() but wish to interrogate the buffer * using the cpu, yet do not wish to teardown the dma mapping, you must * call this function before doing so. At the next point you give the dma * address back to the card, you must first perform a @@ -777,7 +775,7 @@ EXPORT_SYMBOL_GPL(swiotlb_sync_single_range_for_device); /* * Map a set of buffers described by scatterlist in streaming mode for DMA. - * This is the scatter-gather version of the above swiotlb_map_single + * This is the scatter-gather version of the above swiotlb_map_page * interface. Here the scatter gather list elements are each tagged with the * appropriate dma address and length. They are obtained via * sg_dma_{address,length}(SG). @@ -788,7 +786,7 @@ EXPORT_SYMBOL_GPL(swiotlb_sync_single_range_for_device); * The routine returns the number of addr/length pairs actually * used, at most nents. * - * Device ownership issues as mentioned above for swiotlb_map_single are the + * Device ownership issues as mentioned above for swiotlb_map_page are the * same here. */ int @@ -836,7 +834,7 @@ EXPORT_SYMBOL(swiotlb_map_sg); /* * Unmap a set of streaming mode DMA translations. Again, cpu read rules - * concerning calls here are the same as for swiotlb_unmap_single() above. + * concerning calls here are the same as for swiotlb_unmap_page() above. */ void swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl, -- cgit v1.2.3 From 67131ad0514d7105b55003a0506209cf1bba3f00 Mon Sep 17 00:00:00 2001 From: Becky Bruce Date: Wed, 8 Apr 2009 09:09:16 -0500 Subject: swiotlb: fix compile warning Squash a build warning seen on 32-bit powerpc caused by calling min() with 2 different types. Use min_t() instead. Signed-off-by: Becky Bruce Acked-by: FUJITA Tomonori Signed-off-by: Kumar Gala Cc: jeremy@goop.org Cc: ian.campbell@citrix.com LKML-Reference: <1239199761-22886-3-git-send-email-galak@kernel.crashing.org> Signed-off-by: Ingo Molnar --- lib/swiotlb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'lib/swiotlb.c') diff --git a/lib/swiotlb.c b/lib/swiotlb.c index 170cf56af6a..4fd6a76e728 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -341,7 +341,7 @@ static void swiotlb_bounce(phys_addr_t phys, char *dma_addr, size_t size, unsigned long flags; while (size) { - sz = min(PAGE_SIZE - offset, size); + sz = min_t(size_t, PAGE_SIZE - offset, size); local_irq_save(flags); buffer = kmap_atomic(pfn_to_page(pfn), -- cgit v1.2.3 From dd6b02fe427f30520d0adc94aa52352367227873 Mon Sep 17 00:00:00 2001 From: Becky Bruce Date: Wed, 8 Apr 2009 09:09:17 -0500 Subject: swiotlb: map_page fix for highmem systems The current code calls virt_to_phys() on address that might be in highmem, which is bad. This wasn't needed, anyway, because we already have the physical address we need. Get rid of the now-unused virtual address as well. Signed-off-by: Becky Bruce Acked-by: FUJITA Tomonori Signed-off-by: Kumar Gala Cc: jeremy@goop.org Cc: ian.campbell@citrix.com LKML-Reference: <1239199761-22886-4-git-send-email-galak@kernel.crashing.org> Signed-off-by: Ingo Molnar --- lib/swiotlb.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'lib/swiotlb.c') diff --git a/lib/swiotlb.c b/lib/swiotlb.c index 4fd6a76e728..e8a47c8cf77 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -640,7 +640,6 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page, struct dma_attrs *attrs) { phys_addr_t phys = page_to_phys(page) + offset; - void *ptr = page_address(page) + offset; dma_addr_t dev_addr = swiotlb_phys_to_bus(dev, phys); void *map; @@ -651,7 +650,7 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page, * buffering it. */ if (!address_needs_mapping(dev, dev_addr, size) && - !range_needs_mapping(virt_to_phys(ptr), size)) + !range_needs_mapping(phys, size)) return dev_addr; /* -- cgit v1.2.3 From ef5722f698bde01cfec2b98fff733a48663ebf55 Mon Sep 17 00:00:00 2001 From: Becky Bruce Date: Wed, 8 Apr 2009 09:09:18 -0500 Subject: swiotlb: allow arch override of address_needs_mapping Some architectures require additional checking to determine if a device can dma to an address and need to provide their own address_needs_mapping.. Signed-off-by: Becky Bruce Acked-by: FUJITA Tomonori Signed-off-by: Kumar Gala Cc: jeremy@goop.org Cc: ian.campbell@citrix.com LKML-Reference: <1239199761-22886-5-git-send-email-galak@kernel.crashing.org> Signed-off-by: Ingo Molnar --- lib/swiotlb.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'lib/swiotlb.c') diff --git a/lib/swiotlb.c b/lib/swiotlb.c index e8a47c8cf77..d81afab8516 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -145,6 +145,12 @@ static void *swiotlb_bus_to_virt(dma_addr_t address) return phys_to_virt(swiotlb_bus_to_phys(address)); } +int __weak swiotlb_arch_address_needs_mapping(struct device *hwdev, + dma_addr_t addr, size_t size) +{ + return !is_buffer_dma_capable(dma_get_mask(hwdev), addr, size); +} + int __weak swiotlb_arch_range_needs_mapping(phys_addr_t paddr, size_t size) { return 0; @@ -309,10 +315,10 @@ cleanup1: return -ENOMEM; } -static int +static inline int address_needs_mapping(struct device *hwdev, dma_addr_t addr, size_t size) { - return !is_buffer_dma_capable(dma_get_mask(hwdev), addr, size); + return swiotlb_arch_address_needs_mapping(hwdev, addr, size); } static inline int range_needs_mapping(phys_addr_t paddr, size_t size) -- cgit v1.2.3 From 7fcebbd2d984eac3fdd6da2f4453e7c43d32de89 Mon Sep 17 00:00:00 2001 From: Becky Bruce Date: Wed, 8 Apr 2009 09:09:19 -0500 Subject: swiotlb: rename unmap_single to do_unmap_single Previously, swiotlb_unmap_page and swiotlb_unmap_sg were duplicating very similar code. Refactor that code into a new unmap_single and unmap_single use do_unmap_single. Note that the swiotlb_unmap_sg code was previously doing a complicated comparison to determine if an addresses needed to be unmapped where a simple is_swiotlb_buffer() call would have sufficed. Signed-off-by: Becky Bruce Signed-off-by: Kumar Gala Cc: jeremy@goop.org Cc: ian.campbell@citrix.com LKML-Reference: <1239199761-22886-6-git-send-email-galak@kernel.crashing.org> Signed-off-by: Ingo Molnar --- lib/swiotlb.c | 42 +++++++++++++++++++++++++----------------- 1 file changed, 25 insertions(+), 17 deletions(-) (limited to 'lib/swiotlb.c') diff --git a/lib/swiotlb.c b/lib/swiotlb.c index d81afab8516..2bde54a40d8 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -482,7 +482,7 @@ found: * dma_addr is the kernel virtual address of the bounce buffer to unmap. */ static void -unmap_single(struct device *hwdev, char *dma_addr, size_t size, int dir) +do_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; @@ -591,7 +591,7 @@ swiotlb_alloc_coherent(struct device *hwdev, size_t size, (unsigned long long)dev_addr); /* DMA_TO_DEVICE to avoid memcpy in unmap_single */ - unmap_single(hwdev, ret, size, DMA_TO_DEVICE); + do_unmap_single(hwdev, ret, size, DMA_TO_DEVICE); return NULL; } *dma_handle = dev_addr; @@ -608,7 +608,7 @@ swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr, free_pages((unsigned long) vaddr, get_order(size)); else /* DMA_TO_DEVICE to avoid memcpy in unmap_single */ - unmap_single(hwdev, vaddr, size, DMA_TO_DEVICE); + do_unmap_single(hwdev, vaddr, size, DMA_TO_DEVICE); } EXPORT_SYMBOL(swiotlb_free_coherent); @@ -688,17 +688,29 @@ EXPORT_SYMBOL_GPL(swiotlb_map_page); * After this call, reads by the cpu to the buffer are guaranteed to see * whatever the device wrote there. */ -void swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr, - size_t size, enum dma_data_direction dir, - struct dma_attrs *attrs) +static void unmap_single(struct device *hwdev, dma_addr_t dev_addr, + size_t size, int dir) { char *dma_addr = swiotlb_bus_to_virt(dev_addr); BUG_ON(dir == DMA_NONE); - if (is_swiotlb_buffer(dma_addr)) - unmap_single(hwdev, dma_addr, size, dir); - else if (dir == DMA_FROM_DEVICE) - dma_mark_clean(dma_addr, size); + + if (is_swiotlb_buffer(dma_addr)) { + do_unmap_single(hwdev, dma_addr, size, dir); + return; + } + + if (dir != DMA_FROM_DEVICE) + return; + + dma_mark_clean(dma_addr, size); +} + +void swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr, + size_t size, enum dma_data_direction dir, + struct dma_attrs *attrs) +{ + unmap_single(hwdev, dev_addr, size, dir); } EXPORT_SYMBOL_GPL(swiotlb_unmap_page); @@ -850,13 +862,9 @@ swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl, BUG_ON(dir == DMA_NONE); - for_each_sg(sgl, sg, nelems, i) { - if (sg->dma_address != swiotlb_phys_to_bus(hwdev, sg_phys(sg))) - unmap_single(hwdev, swiotlb_bus_to_virt(sg->dma_address), - sg->dma_length, dir); - else if (dir == DMA_FROM_DEVICE) - dma_mark_clean(swiotlb_bus_to_virt(sg->dma_address), sg->dma_length); - } + for_each_sg(sgl, sg, nelems, i) + unmap_single(hwdev, sg->dma_address, sg->dma_length, dir); + } EXPORT_SYMBOL(swiotlb_unmap_sg_attrs); -- cgit v1.2.3 From 380d687833aee098c4a2c3b35beaefe1c1f48d01 Mon Sep 17 00:00:00 2001 From: Becky Bruce Date: Wed, 8 Apr 2009 09:09:20 -0500 Subject: swiotlb: use swiotlb_sync_single instead of duplicating code Right now both swiotlb_sync_single_range and swiotlb_sync_sg were duplicating the code in swiotlb_sync_single. Just call it instead. Also rearrange the sync_single code for readability. Note that the swiotlb_sync_sg code was previously doing a complicated comparison to determine if an addresses needed to be unmapped where a simple is_swiotlb_buffer() call would have sufficed. Signed-off-by: Becky Bruce Acked-by: FUJITA Tomonori Signed-off-by: Kumar Gala Cc: jeremy@goop.org Cc: ian.campbell@citrix.com LKML-Reference: <1239199761-22886-7-git-send-email-galak@kernel.crashing.org> Signed-off-by: Ingo Molnar --- lib/swiotlb.c | 30 ++++++++++++------------------ 1 file changed, 12 insertions(+), 18 deletions(-) (limited to 'lib/swiotlb.c') diff --git a/lib/swiotlb.c b/lib/swiotlb.c index 2bde54a40d8..d912f068145 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -731,10 +731,16 @@ swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr, char *dma_addr = swiotlb_bus_to_virt(dev_addr); BUG_ON(dir == DMA_NONE); - if (is_swiotlb_buffer(dma_addr)) + + if (is_swiotlb_buffer(dma_addr)) { sync_single(hwdev, dma_addr, size, dir, target); - else if (dir == DMA_FROM_DEVICE) - dma_mark_clean(dma_addr, size); + return; + } + + if (dir != DMA_FROM_DEVICE) + return; + + dma_mark_clean(dma_addr, size); } void @@ -761,13 +767,7 @@ swiotlb_sync_single_range(struct device *hwdev, dma_addr_t dev_addr, unsigned long offset, size_t size, int dir, int target) { - char *dma_addr = swiotlb_bus_to_virt(dev_addr) + offset; - - BUG_ON(dir == DMA_NONE); - if (is_swiotlb_buffer(dma_addr)) - sync_single(hwdev, dma_addr, size, dir, target); - else if (dir == DMA_FROM_DEVICE) - dma_mark_clean(dma_addr, size); + swiotlb_sync_single(hwdev, dev_addr + offset, size, dir, target); } void @@ -890,15 +890,9 @@ swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sgl, struct scatterlist *sg; int i; - BUG_ON(dir == DMA_NONE); - - for_each_sg(sgl, sg, nelems, i) { - if (sg->dma_address != swiotlb_phys_to_bus(hwdev, sg_phys(sg))) - sync_single(hwdev, swiotlb_bus_to_virt(sg->dma_address), + for_each_sg(sgl, sg, nelems, i) + swiotlb_sync_single(hwdev, sg->dma_address, sg->dma_length, dir, target); - else if (dir == DMA_FROM_DEVICE) - dma_mark_clean(swiotlb_bus_to_virt(sg->dma_address), sg->dma_length); - } } void -- cgit v1.2.3 From 42d7c5e353cef9062129b0de3ec9ddf10567b9ca Mon Sep 17 00:00:00 2001 From: Becky Bruce Date: Wed, 8 Apr 2009 09:09:21 -0500 Subject: swiotlb: change swiotlb_bus_to[phys,virt] prototypes Add a hwdev argument that is needed on some architectures in order to access a per-device offset that is taken into account when producing a physical address (also needed to get from bus address to virtual address because the physical address is an intermediate step). Also make swiotlb_bus_to_virt weak so architectures can override it. Signed-off-by: Becky Bruce Acked-by: FUJITA Tomonori Signed-off-by: Kumar Gala Cc: jeremy@goop.org Cc: ian.campbell@citrix.com LKML-Reference: <1239199761-22886-8-git-send-email-galak@kernel.crashing.org> Signed-off-by: Ingo Molnar --- lib/swiotlb.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'lib/swiotlb.c') diff --git a/lib/swiotlb.c b/lib/swiotlb.c index d912f068145..bffe6d7ef9d 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -129,7 +129,7 @@ dma_addr_t __weak swiotlb_phys_to_bus(struct device *hwdev, phys_addr_t paddr) return paddr; } -phys_addr_t __weak swiotlb_bus_to_phys(dma_addr_t baddr) +phys_addr_t __weak swiotlb_bus_to_phys(struct device *hwdev, dma_addr_t baddr) { return baddr; } @@ -140,9 +140,9 @@ static dma_addr_t swiotlb_virt_to_bus(struct device *hwdev, return swiotlb_phys_to_bus(hwdev, virt_to_phys(address)); } -static void *swiotlb_bus_to_virt(dma_addr_t address) +void * __weak swiotlb_bus_to_virt(struct device *hwdev, dma_addr_t address) { - return phys_to_virt(swiotlb_bus_to_phys(address)); + return phys_to_virt(swiotlb_bus_to_phys(hwdev, address)); } int __weak swiotlb_arch_address_needs_mapping(struct device *hwdev, @@ -691,7 +691,7 @@ EXPORT_SYMBOL_GPL(swiotlb_map_page); static void unmap_single(struct device *hwdev, dma_addr_t dev_addr, size_t size, int dir) { - char *dma_addr = swiotlb_bus_to_virt(dev_addr); + char *dma_addr = swiotlb_bus_to_virt(hwdev, dev_addr); BUG_ON(dir == DMA_NONE); @@ -728,7 +728,7 @@ static void swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr, size_t size, int dir, int target) { - char *dma_addr = swiotlb_bus_to_virt(dev_addr); + char *dma_addr = swiotlb_bus_to_virt(hwdev, dev_addr); BUG_ON(dir == DMA_NONE); -- cgit v1.2.3