From 0df4f266b3af90442bbeb5e685a84a80745beba0 Mon Sep 17 00:00:00 2001 From: Julien Grall Date: Fri, 7 Aug 2015 17:34:37 +0100 Subject: xen: Use correctly the Xen memory terminologies Based on include/xen/mm.h [1], Linux is mistakenly using MFN when GFN is meant, I suspect this is because the first support for Xen was for PV. This resulted in some misimplementation of helpers on ARM and confused developers about the expected behavior. For instance, with pfn_to_mfn, we expect to get an MFN based on the name. Although, if we look at the implementation on x86, it's returning a GFN. For clarity and avoid new confusion, replace any reference to mfn with gfn in any helpers used by PV drivers. The x86 code will still keep some reference of pfn_to_mfn which may be used by all kind of guests No changes as been made in the hypercall field, even though they may be invalid, in order to keep the same as the defintion in xen repo. Note that page_to_mfn has been renamed to xen_page_to_gfn to avoid a name to close to the KVM function gfn_to_page. Take also the opportunity to simplify simple construction such as pfn_to_mfn(page_to_pfn(page)) into xen_page_to_gfn. More complex clean up will come in follow-up patches. [1] http://xenbits.xen.org/gitweb/?p=xen.git;a=commitdiff;h=e758ed14f390342513405dd766e874934573e6cb Signed-off-by: Julien Grall Reviewed-by: Stefano Stabellini Acked-by: Dmitry Torokhov Acked-by: Wei Liu Signed-off-by: David Vrabel --- include/xen/page.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/xen/page.h b/include/xen/page.h index a5983da2f5cd..1daae485e336 100644 --- a/include/xen/page.h +++ b/include/xen/page.h @@ -3,9 +3,9 @@ #include -static inline unsigned long page_to_mfn(struct page *page) +static inline unsigned long xen_page_to_gfn(struct page *page) { - return pfn_to_mfn(page_to_pfn(page)); + return pfn_to_gfn(page_to_pfn(page)); } struct xen_memory_region { -- cgit v1.2.3 From a13d7201d7deedcbb6ac6efa94a1a7d34d3d79ec Mon Sep 17 00:00:00 2001 From: Julien Grall Date: Fri, 7 Aug 2015 17:34:41 +0100 Subject: xen/privcmd: Further s/MFN/GFN/ clean-up The privcmd code is mixing the usage of GFN and MFN within the same functions which make the code difficult to understand when you only work with auto-translated guests. The privcmd driver is only dealing with GFN so replace all the mention of MFN into GFN. The ioctl structure used to map foreign change has been left unchanged given that the userspace is using it. Nonetheless, add a comment to explain the expected value within the "mfn" field. Signed-off-by: Julien Grall Reviewed-by: David Vrabel Signed-off-by: David Vrabel --- include/uapi/xen/privcmd.h | 4 ++++ include/xen/xen-ops.h | 10 +++++----- 2 files changed, 9 insertions(+), 5 deletions(-) (limited to 'include') diff --git a/include/uapi/xen/privcmd.h b/include/uapi/xen/privcmd.h index a85316811d79..7ddeeda93809 100644 --- a/include/uapi/xen/privcmd.h +++ b/include/uapi/xen/privcmd.h @@ -44,6 +44,10 @@ struct privcmd_hypercall { struct privcmd_mmap_entry { __u64 va; + /* + * This should be a GFN. It's not possible to change the name because + * it's exposed to the user-space. + */ __u64 mfn; __u64 npages; }; diff --git a/include/xen/xen-ops.h b/include/xen/xen-ops.h index 0ce4f32017ea..e4e214a5abd5 100644 --- a/include/xen/xen-ops.h +++ b/include/xen/xen-ops.h @@ -30,7 +30,7 @@ void xen_destroy_contiguous_region(phys_addr_t pstart, unsigned int order); struct vm_area_struct; /* - * xen_remap_domain_mfn_array() - map an array of foreign frames + * xen_remap_domain_gfn_array() - map an array of foreign frames * @vma: VMA to map the pages into * @addr: Address at which to map the pages * @gfn: Array of GFNs to map @@ -46,14 +46,14 @@ struct vm_area_struct; * Returns the number of successfully mapped frames, or a -ve error * code. */ -int xen_remap_domain_mfn_array(struct vm_area_struct *vma, +int xen_remap_domain_gfn_array(struct vm_area_struct *vma, unsigned long addr, xen_pfn_t *gfn, int nr, int *err_ptr, pgprot_t prot, unsigned domid, struct page **pages); -/* xen_remap_domain_mfn_range() - map a range of foreign frames +/* xen_remap_domain_gfn_range() - map a range of foreign frames * @vma: VMA to map the pages into * @addr: Address at which to map the pages * @gfn: First GFN to map. @@ -65,12 +65,12 @@ int xen_remap_domain_mfn_array(struct vm_area_struct *vma, * Returns the number of successfully mapped frames, or a -ve error * code. */ -int xen_remap_domain_mfn_range(struct vm_area_struct *vma, +int xen_remap_domain_gfn_range(struct vm_area_struct *vma, unsigned long addr, xen_pfn_t gfn, int nr, pgprot_t prot, unsigned domid, struct page **pages); -int xen_unmap_domain_mfn_range(struct vm_area_struct *vma, +int xen_unmap_domain_gfn_range(struct vm_area_struct *vma, int numpgs, struct page **pages); int xen_xlate_remap_gfn_array(struct vm_area_struct *vma, unsigned long addr, -- cgit v1.2.3