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author | Stefano Stabellini <stefano.stabellini@eu.citrix.com> | 2013-10-10 13:41:10 +0000 |
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committer | Stefano Stabellini <stefano.stabellini@eu.citrix.com> | 2013-10-10 13:41:10 +0000 |
commit | 1b65c4e5a9af1a1c61e792e2d0ed481e0c1f21a9 (patch) | |
tree | 15c7b03e6efede8905f3729de488341c9a9da81b | |
parent | d6fe76c58c358498b91d21f0ca8054f6aa6e672d (diff) | |
download | op-kernel-dev-1b65c4e5a9af1a1c61e792e2d0ed481e0c1f21a9.zip op-kernel-dev-1b65c4e5a9af1a1c61e792e2d0ed481e0c1f21a9.tar.gz |
swiotlb-xen: use xen_alloc/free_coherent_pages
Use xen_alloc_coherent_pages and xen_free_coherent_pages to allocate or
free coherent pages.
We need to be careful handling the pointer returned by
xen_alloc_coherent_pages, because on ARM the pointer is not equal to
phys_to_virt(*dma_handle). In fact virt_to_phys only works for kernel
direct mapped RAM memory.
In ARM case the pointer could be an ioremap address, therefore passing
it to virt_to_phys would give you another physical address that doesn't
correspond to it.
Make xen_create_contiguous_region take a phys_addr_t as start parameter to
avoid the virt_to_phys calls which would be incorrect.
Changes in v6:
- remove extra spaces.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
-rw-r--r-- | arch/arm/xen/mm.c | 6 | ||||
-rw-r--r-- | arch/x86/xen/mmu.c | 7 | ||||
-rw-r--r-- | drivers/xen/swiotlb-xen.c | 31 | ||||
-rw-r--r-- | include/xen/xen-ops.h | 4 |
4 files changed, 31 insertions, 17 deletions
diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c index 0d69b87..b0e77de 100644 --- a/arch/arm/xen/mm.c +++ b/arch/arm/xen/mm.c @@ -16,7 +16,7 @@ #include <asm/xen/hypercall.h> #include <asm/xen/interface.h> -int xen_create_contiguous_region(unsigned long vstart, unsigned int order, +int xen_create_contiguous_region(phys_addr_t pstart, unsigned int order, unsigned int address_bits, dma_addr_t *dma_handle) { @@ -24,12 +24,12 @@ int xen_create_contiguous_region(unsigned long vstart, unsigned int order, return -EINVAL; /* we assume that dom0 is mapped 1:1 for now */ - *dma_handle = virt_to_phys(pstart); + *dma_handle = pstart; return 0; } EXPORT_SYMBOL_GPL(xen_create_contiguous_region); -void xen_destroy_contiguous_region(unsigned long vstart, unsigned int order) +void xen_destroy_contiguous_region(phys_addr_t pstart, unsigned int order) { return; } diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 6c34d7c..8830883 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -2328,13 +2328,14 @@ static int xen_exchange_memory(unsigned long extents_in, unsigned int order_in, return success; } -int xen_create_contiguous_region(unsigned long vstart, unsigned int order, +int xen_create_contiguous_region(phys_addr_t pstart, unsigned int order, unsigned int address_bits, dma_addr_t *dma_handle) { unsigned long *in_frames = discontig_frames, out_frame; unsigned long flags; int success; + unsigned long vstart = (unsigned long)phys_to_virt(pstart); /* * Currently an auto-translated guest will not perform I/O, nor will @@ -2374,11 +2375,12 @@ int xen_create_contiguous_region(unsigned long vstart, unsigned int order, } EXPORT_SYMBOL_GPL(xen_create_contiguous_region); -void xen_destroy_contiguous_region(unsigned long vstart, unsigned int order) +void xen_destroy_contiguous_region(phys_addr_t pstart, unsigned int order) { unsigned long *out_frames = discontig_frames, in_frame; unsigned long flags; int success; + unsigned long vstart; if (xen_feature(XENFEAT_auto_translated_physmap)) return; @@ -2386,6 +2388,7 @@ void xen_destroy_contiguous_region(unsigned long vstart, unsigned int order) if (unlikely(order > MAX_CONTIG_ORDER)) return; + vstart = (unsigned long)phys_to_virt(pstart); memset((void *) vstart, 0, PAGE_SIZE << order); spin_lock_irqsave(&xen_reservation_lock, flags); diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index d8ef0bf..189b8db 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -43,6 +43,7 @@ #include <xen/xen-ops.h> #include <xen/hvc-console.h> #include <asm/dma-mapping.h> +#include <asm/xen/page-coherent.h> /* * Used to do a quick range check in swiotlb_tbl_unmap_single and * swiotlb_tbl_sync_single_*, to see if the memory was in fact allocated by this @@ -142,6 +143,7 @@ xen_swiotlb_fixup(void *buf, size_t size, unsigned long nslabs) int i, rc; int dma_bits; dma_addr_t dma_handle; + phys_addr_t p = virt_to_phys(buf); dma_bits = get_order(IO_TLB_SEGSIZE << IO_TLB_SHIFT) + PAGE_SHIFT; @@ -151,7 +153,7 @@ xen_swiotlb_fixup(void *buf, size_t size, unsigned long nslabs) do { rc = xen_create_contiguous_region( - (unsigned long)buf + (i << IO_TLB_SHIFT), + p + (i << IO_TLB_SHIFT), get_order(slabs << IO_TLB_SHIFT), dma_bits, &dma_handle); } while (rc && dma_bits++ < max_dma_bits); @@ -279,7 +281,6 @@ xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size, void *ret; int order = get_order(size); u64 dma_mask = DMA_BIT_MASK(32); - unsigned long vstart; phys_addr_t phys; dma_addr_t dev_addr; @@ -294,8 +295,12 @@ xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size, if (dma_alloc_from_coherent(hwdev, size, dma_handle, &ret)) return ret; - vstart = __get_free_pages(flags, order); - ret = (void *)vstart; + /* On ARM this function returns an ioremap'ped virtual address for + * which virt_to_phys doesn't return the corresponding physical + * address. In fact on ARM virt_to_phys only works for kernel direct + * mapped RAM memory. Also see comment below. + */ + ret = xen_alloc_coherent_pages(hwdev, size, dma_handle, flags, attrs); if (!ret) return ret; @@ -303,15 +308,19 @@ xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size, if (hwdev && hwdev->coherent_dma_mask) dma_mask = dma_alloc_coherent_mask(hwdev, flags); - phys = virt_to_phys(ret); + /* At this point dma_handle is the physical address, next we are + * going to set it to the machine address. + * Do not use virt_to_phys(ret) because on ARM it doesn't correspond + * to *dma_handle. */ + phys = *dma_handle; dev_addr = xen_phys_to_bus(phys); if (((dev_addr + size - 1 <= dma_mask)) && !range_straddles_page_boundary(phys, size)) *dma_handle = dev_addr; else { - if (xen_create_contiguous_region(vstart, order, + if (xen_create_contiguous_region(phys, order, fls64(dma_mask), dma_handle) != 0) { - free_pages(vstart, order); + xen_free_coherent_pages(hwdev, size, ret, (dma_addr_t)phys, attrs); return NULL; } } @@ -334,13 +343,15 @@ xen_swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr, if (hwdev && hwdev->coherent_dma_mask) dma_mask = hwdev->coherent_dma_mask; - phys = virt_to_phys(vaddr); + /* do not use virt_to_phys because on ARM it doesn't return you the + * physical address */ + phys = xen_bus_to_phys(dev_addr); if (((dev_addr + size - 1 > dma_mask)) || range_straddles_page_boundary(phys, size)) - xen_destroy_contiguous_region((unsigned long)vaddr, order); + xen_destroy_contiguous_region(phys, order); - free_pages((unsigned long)vaddr, order); + xen_free_coherent_pages(hwdev, size, vaddr, (dma_addr_t)phys, attrs); } EXPORT_SYMBOL_GPL(xen_swiotlb_free_coherent); diff --git a/include/xen/xen-ops.h b/include/xen/xen-ops.h index 9ef704d..fb2ea8f 100644 --- a/include/xen/xen-ops.h +++ b/include/xen/xen-ops.h @@ -19,11 +19,11 @@ void xen_arch_resume(void); int xen_setup_shutdown_event(void); extern unsigned long *xen_contiguous_bitmap; -int xen_create_contiguous_region(unsigned long vstart, unsigned int order, +int xen_create_contiguous_region(phys_addr_t pstart, unsigned int order, unsigned int address_bits, dma_addr_t *dma_handle); -void xen_destroy_contiguous_region(unsigned long vstart, unsigned int order); +void xen_destroy_contiguous_region(phys_addr_t pstart, unsigned int order); struct vm_area_struct; int xen_remap_domain_mfn_range(struct vm_area_struct *vma, |