From 19001c8c5bfa032ed45b10dfe48e355f5df88c61 Mon Sep 17 00:00:00 2001 From: Alex Nixon Date: Mon, 9 Feb 2009 12:05:46 -0800 Subject: xen: Rename the balloon lock * xen_create_contiguous_region needs access to the balloon lock to ensure memory doesn't change under its feet, so expose the balloon lock * Change the name of the lock to xen_reservation_lock, to imply it's now less-specific usage. [ Impact: cleanup ] Signed-off-by: Alex Nixon Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Konrad Rzeszutek Wilk --- include/xen/interface/memory.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'include/xen') diff --git a/include/xen/interface/memory.h b/include/xen/interface/memory.h index af36ead1681..e6adce6bc75 100644 --- a/include/xen/interface/memory.h +++ b/include/xen/interface/memory.h @@ -9,6 +9,8 @@ #ifndef __XEN_PUBLIC_MEMORY_H__ #define __XEN_PUBLIC_MEMORY_H__ +#include + /* * Increase or decrease the specified domain's memory reservation. Returns a * -ve errcode on failure, or the # extents successfully allocated or freed. @@ -142,4 +144,10 @@ struct xen_translate_gpfn_list { }; DEFINE_GUEST_HANDLE_STRUCT(xen_translate_gpfn_list); + +/* + * Prevent the balloon driver from changing the memory reservation + * during a driver critical region. + */ +extern spinlock_t xen_reservation_lock; #endif /* __XEN_PUBLIC_MEMORY_H__ */ -- cgit v1.2.3 From 08bbc9da92f7e44b9c208c6a1adba70c403b255e Mon Sep 17 00:00:00 2001 From: Alex Nixon Date: Mon, 9 Feb 2009 12:05:46 -0800 Subject: xen: Add xen_create_contiguous_region A memory region must be physically contiguous in order to be accessed through DMA. This patch adds xen_create_contiguous_region, which ensures a region of contiguous virtual memory is also physically contiguous. Based on Stephen Tweedie's port of the 2.6.18-xen version. Remove contiguous_bitmap[] as it's no longer needed. Ported from linux-2.6.18-xen.hg 707:e410857fd83c [ Impact: add Xen-internal API to make pages phys-contig ] Signed-off-by: Alex Nixon Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Ian Campbell Signed-off-by: Konrad Rzeszutek Wilk --- include/xen/interface/memory.h | 42 ++++++++++++++++++++++++++++++++++++++++++ include/xen/xen-ops.h | 6 ++++++ 2 files changed, 48 insertions(+) (limited to 'include/xen') diff --git a/include/xen/interface/memory.h b/include/xen/interface/memory.h index e6adce6bc75..d3938d3e71f 100644 --- a/include/xen/interface/memory.h +++ b/include/xen/interface/memory.h @@ -54,6 +54,48 @@ struct xen_memory_reservation { }; DEFINE_GUEST_HANDLE_STRUCT(xen_memory_reservation); +/* + * An atomic exchange of memory pages. If return code is zero then + * @out.extent_list provides GMFNs of the newly-allocated memory. + * Returns zero on complete success, otherwise a negative error code. + * On complete success then always @nr_exchanged == @in.nr_extents. + * On partial success @nr_exchanged indicates how much work was done. + */ +#define XENMEM_exchange 11 +struct xen_memory_exchange { + /* + * [IN] Details of memory extents to be exchanged (GMFN bases). + * Note that @in.address_bits is ignored and unused. + */ + struct xen_memory_reservation in; + + /* + * [IN/OUT] Details of new memory extents. + * We require that: + * 1. @in.domid == @out.domid + * 2. @in.nr_extents << @in.extent_order == + * @out.nr_extents << @out.extent_order + * 3. @in.extent_start and @out.extent_start lists must not overlap + * 4. @out.extent_start lists GPFN bases to be populated + * 5. @out.extent_start is overwritten with allocated GMFN bases + */ + struct xen_memory_reservation out; + + /* + * [OUT] Number of input extents that were successfully exchanged: + * 1. The first @nr_exchanged input extents were successfully + * deallocated. + * 2. The corresponding first entries in the output extent list correctly + * indicate the GMFNs that were successfully exchanged. + * 3. All other input and output extents are untouched. + * 4. If not all input exents are exchanged then the return code of this + * command will be non-zero. + * 5. THIS FIELD MUST BE INITIALISED TO ZERO BY THE CALLER! + */ + unsigned long nr_exchanged; +}; + +DEFINE_GUEST_HANDLE_STRUCT(xen_memory_exchange); /* * Returns the maximum machine frame number of mapped RAM in this system. * This command always succeeds (it never returns an error code). diff --git a/include/xen/xen-ops.h b/include/xen/xen-ops.h index 883a21bba24..d789c937c48 100644 --- a/include/xen/xen-ops.h +++ b/include/xen/xen-ops.h @@ -14,4 +14,10 @@ void xen_mm_unpin_all(void); void xen_timer_resume(void); void xen_arch_resume(void); +extern unsigned long *xen_contiguous_bitmap; +int xen_create_contiguous_region(unsigned long vstart, unsigned int order, + unsigned int address_bits); + +void xen_destroy_contiguous_region(unsigned long vstart, unsigned int order); + #endif /* INCLUDE_XEN_OPS_H */ -- cgit v1.2.3 From b097186fd29d5bc5a26d1ae87995821ffc27b66e Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Tue, 11 May 2010 10:05:49 -0400 Subject: swiotlb-xen: SWIOTLB library for Xen PV guest with PCI passthrough. This patchset: PV guests under Xen are running in an non-contiguous memory architecture. When PCI pass-through is utilized, this necessitates an IOMMU for translating bus (DMA) to virtual and vice-versa and also providing a mechanism to have contiguous pages for device drivers operations (say DMA operations). Specifically, under Xen the Linux idea of pages is an illusion. It assumes that pages start at zero and go up to the available memory. To help with that, the Linux Xen MMU provides a lookup mechanism to translate the page frame numbers (PFN) to machine frame numbers (MFN) and vice-versa. The MFN are the "real" frame numbers. Furthermore memory is not contiguous. Xen hypervisor stitches memory for guests from different pools, which means there is no guarantee that PFN==MFN and PFN+1==MFN+1. Lastly with Xen 4.0, pages (in debug mode) are allocated in descending order (high to low), meaning the guest might never get any MFN's under the 4GB mark. Signed-off-by: Konrad Rzeszutek Wilk Acked-by: Jeremy Fitzhardinge Cc: FUJITA Tomonori Cc: Albert Herranz Cc: Ian Campbell --- include/xen/swiotlb-xen.h | 65 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 include/xen/swiotlb-xen.h (limited to 'include/xen') diff --git a/include/xen/swiotlb-xen.h b/include/xen/swiotlb-xen.h new file mode 100644 index 00000000000..2ea2fdc79c1 --- /dev/null +++ b/include/xen/swiotlb-xen.h @@ -0,0 +1,65 @@ +#ifndef __LINUX_SWIOTLB_XEN_H +#define __LINUX_SWIOTLB_XEN_H + +#include + +extern void xen_swiotlb_init(int verbose); + +extern void +*xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size, + dma_addr_t *dma_handle, gfp_t flags); + +extern void +xen_swiotlb_free_coherent(struct device *hwdev, size_t size, + void *vaddr, dma_addr_t dma_handle); + +extern dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, + enum dma_data_direction dir, + struct dma_attrs *attrs); + +extern void xen_swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr, + size_t size, enum dma_data_direction dir, + struct dma_attrs *attrs); +/* +extern int +xen_swiotlb_map_sg(struct device *hwdev, struct scatterlist *sg, int nents, + enum dma_data_direction dir); + +extern void +xen_swiotlb_unmap_sg(struct device *hwdev, struct scatterlist *sg, int nents, + enum dma_data_direction dir); +*/ +extern int +xen_swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, + int nelems, enum dma_data_direction dir, + struct dma_attrs *attrs); + +extern void +xen_swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl, + int nelems, enum dma_data_direction dir, + struct dma_attrs *attrs); + +extern void +xen_swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr, + size_t size, enum dma_data_direction dir); + +extern void +xen_swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg, + int nelems, enum dma_data_direction dir); + +extern void +xen_swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr, + size_t size, enum dma_data_direction dir); + +extern void +xen_swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg, + int nelems, enum dma_data_direction dir); + +extern int +xen_swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr); + +extern int +xen_swiotlb_dma_supported(struct device *hwdev, u64 mask); + +#endif /* __LINUX_SWIOTLB_XEN_H */ -- cgit v1.2.3