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 --- arch/arm/xen/enlighten.c | 18 +++++++++--------- arch/x86/xen/mmu.c | 32 ++++++++++++++++---------------- drivers/xen/privcmd.c | 44 ++++++++++++++++++++++---------------------- drivers/xen/xlate_mmu.c | 18 +++++++++--------- include/uapi/xen/privcmd.h | 4 ++++ include/xen/xen-ops.h | 10 +++++----- 6 files changed, 65 insertions(+), 61 deletions(-) (limited to 'include') diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c index c50c8d33f874..eeeab074e154 100644 --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -49,35 +49,35 @@ static __read_mostly unsigned int xen_events_irq; static __initdata struct device_node *xen_node; -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 *mfn, int nr, + xen_pfn_t *gfn, int nr, int *err_ptr, pgprot_t prot, unsigned domid, struct page **pages) { - return xen_xlate_remap_gfn_array(vma, addr, mfn, nr, err_ptr, + return xen_xlate_remap_gfn_array(vma, addr, gfn, nr, err_ptr, prot, domid, pages); } -EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_array); +EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_array); /* Not used by XENFEAT_auto_translated guests. */ -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 mfn, int nr, + xen_pfn_t gfn, int nr, pgprot_t prot, unsigned domid, struct page **pages) { return -ENOSYS; } -EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range); +EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_range); -int xen_unmap_domain_mfn_range(struct vm_area_struct *vma, +int xen_unmap_domain_gfn_range(struct vm_area_struct *vma, int nr, struct page **pages) { return xen_xlate_unmap_gfn_range(vma, nr, pages); } -EXPORT_SYMBOL_GPL(xen_unmap_domain_mfn_range); +EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range); static void xen_percpu_init(void) { diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c index 2c50b445884e..9c479fe40459 100644 --- a/arch/x86/xen/mmu.c +++ b/arch/x86/xen/mmu.c @@ -2812,9 +2812,9 @@ static int remap_area_mfn_pte_fn(pte_t *ptep, pgtable_t token, return 0; } -static int do_remap_mfn(struct vm_area_struct *vma, +static int do_remap_gfn(struct vm_area_struct *vma, unsigned long addr, - xen_pfn_t *mfn, int nr, + xen_pfn_t *gfn, int nr, int *err_ptr, pgprot_t prot, unsigned domid, struct page **pages) @@ -2830,14 +2830,14 @@ static int do_remap_mfn(struct vm_area_struct *vma, if (xen_feature(XENFEAT_auto_translated_physmap)) { #ifdef CONFIG_XEN_PVH /* We need to update the local page tables and the xen HAP */ - return xen_xlate_remap_gfn_array(vma, addr, mfn, nr, err_ptr, + return xen_xlate_remap_gfn_array(vma, addr, gfn, nr, err_ptr, prot, domid, pages); #else return -EINVAL; #endif } - rmd.mfn = mfn; + rmd.mfn = gfn; rmd.prot = prot; /* We use the err_ptr to indicate if there we are doing a contigious * mapping or a discontigious mapping. */ @@ -2865,8 +2865,8 @@ static int do_remap_mfn(struct vm_area_struct *vma, batch_left, &done, domid); /* - * @err_ptr may be the same buffer as @mfn, so - * only clear it after each chunk of @mfn is + * @err_ptr may be the same buffer as @gfn, so + * only clear it after each chunk of @gfn is * used. */ if (err_ptr) { @@ -2896,19 +2896,19 @@ out: return err < 0 ? err : mapped; } -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 mfn, int nr, + xen_pfn_t gfn, int nr, pgprot_t prot, unsigned domid, struct page **pages) { - return do_remap_mfn(vma, addr, &mfn, nr, NULL, prot, domid, pages); + return do_remap_gfn(vma, addr, &gfn, nr, NULL, prot, domid, pages); } -EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_range); +EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_range); -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 *mfn, int nr, + xen_pfn_t *gfn, int nr, int *err_ptr, pgprot_t prot, unsigned domid, struct page **pages) { @@ -2917,13 +2917,13 @@ int xen_remap_domain_mfn_array(struct vm_area_struct *vma, * cause of "wrong memory was mapped in". */ BUG_ON(err_ptr == NULL); - return do_remap_mfn(vma, addr, mfn, nr, err_ptr, prot, domid, pages); + return do_remap_gfn(vma, addr, gfn, nr, err_ptr, prot, domid, pages); } -EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_array); +EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_array); /* Returns: 0 success */ -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) { if (!pages || !xen_feature(XENFEAT_auto_translated_physmap)) @@ -2935,4 +2935,4 @@ int xen_unmap_domain_mfn_range(struct vm_area_struct *vma, return -EINVAL; #endif } -EXPORT_SYMBOL_GPL(xen_unmap_domain_mfn_range); +EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range); diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c index 5a296161d843..c6deb87c5c69 100644 --- a/drivers/xen/privcmd.c +++ b/drivers/xen/privcmd.c @@ -193,16 +193,16 @@ static int traverse_pages_block(unsigned nelem, size_t size, return ret; } -struct mmap_mfn_state { +struct mmap_gfn_state { unsigned long va; struct vm_area_struct *vma; domid_t domain; }; -static int mmap_mfn_range(void *data, void *state) +static int mmap_gfn_range(void *data, void *state) { struct privcmd_mmap_entry *msg = data; - struct mmap_mfn_state *st = state; + struct mmap_gfn_state *st = state; struct vm_area_struct *vma = st->vma; int rc; @@ -216,7 +216,7 @@ static int mmap_mfn_range(void *data, void *state) ((msg->va+(msg->npages< vma->vm_end)) return -EINVAL; - rc = xen_remap_domain_mfn_range(vma, + rc = xen_remap_domain_gfn_range(vma, msg->va & PAGE_MASK, msg->mfn, msg->npages, vma->vm_page_prot, @@ -236,7 +236,7 @@ static long privcmd_ioctl_mmap(void __user *udata) struct vm_area_struct *vma; int rc; LIST_HEAD(pagelist); - struct mmap_mfn_state state; + struct mmap_gfn_state state; /* We only support privcmd_ioctl_mmap_batch for auto translated. */ if (xen_feature(XENFEAT_auto_translated_physmap)) @@ -273,7 +273,7 @@ static long privcmd_ioctl_mmap(void __user *udata) rc = traverse_pages(mmapcmd.num, sizeof(struct privcmd_mmap_entry), &pagelist, - mmap_mfn_range, &state); + mmap_gfn_range, &state); out_up: @@ -299,18 +299,18 @@ struct mmap_batch_state { int global_error; int version; - /* User-space mfn array to store errors in the second pass for V1. */ - xen_pfn_t __user *user_mfn; + /* User-space gfn array to store errors in the second pass for V1. */ + xen_pfn_t __user *user_gfn; /* User-space int array to store errors in the second pass for V2. */ int __user *user_err; }; -/* auto translated dom0 note: if domU being created is PV, then mfn is - * mfn(addr on bus). If it's auto xlated, then mfn is pfn (input to HAP). +/* auto translated dom0 note: if domU being created is PV, then gfn is + * mfn(addr on bus). If it's auto xlated, then gfn is pfn (input to HAP). */ static int mmap_batch_fn(void *data, int nr, void *state) { - xen_pfn_t *mfnp = data; + xen_pfn_t *gfnp = data; struct mmap_batch_state *st = state; struct vm_area_struct *vma = st->vma; struct page **pages = vma->vm_private_data; @@ -321,8 +321,8 @@ static int mmap_batch_fn(void *data, int nr, void *state) cur_pages = &pages[st->index]; BUG_ON(nr < 0); - ret = xen_remap_domain_mfn_array(st->vma, st->va & PAGE_MASK, mfnp, nr, - (int *)mfnp, st->vma->vm_page_prot, + ret = xen_remap_domain_gfn_array(st->vma, st->va & PAGE_MASK, gfnp, nr, + (int *)gfnp, st->vma->vm_page_prot, st->domain, cur_pages); /* Adjust the global_error? */ @@ -347,22 +347,22 @@ static int mmap_return_error(int err, struct mmap_batch_state *st) if (st->version == 1) { if (err) { - xen_pfn_t mfn; + xen_pfn_t gfn; - ret = get_user(mfn, st->user_mfn); + ret = get_user(gfn, st->user_gfn); if (ret < 0) return ret; /* * V1 encodes the error codes in the 32bit top - * nibble of the mfn (with its known + * nibble of the gfn (with its known * limitations vis-a-vis 64 bit callers). */ - mfn |= (err == -ENOENT) ? + gfn |= (err == -ENOENT) ? PRIVCMD_MMAPBATCH_PAGED_ERROR : PRIVCMD_MMAPBATCH_MFN_ERROR; - return __put_user(mfn, st->user_mfn++); + return __put_user(gfn, st->user_gfn++); } else - st->user_mfn++; + st->user_gfn++; } else { /* st->version == 2 */ if (err) return __put_user(err, st->user_err++); @@ -388,7 +388,7 @@ static int mmap_return_errors(void *data, int nr, void *state) return 0; } -/* Allocate pfns that are then mapped with gmfns from foreign domid. Update +/* Allocate pfns that are then mapped with gfns from foreign domid. Update * the vma with the page info to use later. * Returns: 0 if success, otherwise -errno */ @@ -526,7 +526,7 @@ static long privcmd_ioctl_mmap_batch(void __user *udata, int version) if (state.global_error) { /* Write back errors in second pass. */ - state.user_mfn = (xen_pfn_t *)m.arr; + state.user_gfn = (xen_pfn_t *)m.arr; state.user_err = m.err; ret = traverse_pages_block(m.num, sizeof(xen_pfn_t), &pagelist, mmap_return_errors, &state); @@ -587,7 +587,7 @@ static void privcmd_close(struct vm_area_struct *vma) if (!xen_feature(XENFEAT_auto_translated_physmap) || !numpgs || !pages) return; - rc = xen_unmap_domain_mfn_range(vma, numpgs, pages); + rc = xen_unmap_domain_gfn_range(vma, numpgs, pages); if (rc == 0) free_xenballooned_pages(numpgs, pages); else diff --git a/drivers/xen/xlate_mmu.c b/drivers/xen/xlate_mmu.c index 58a5389aec89..cff23872c5a9 100644 --- a/drivers/xen/xlate_mmu.c +++ b/drivers/xen/xlate_mmu.c @@ -38,8 +38,8 @@ #include #include -/* map fgmfn of domid to lpfn in the current domain */ -static int map_foreign_page(unsigned long lpfn, unsigned long fgmfn, +/* map fgfn of domid to lpfn in the current domain */ +static int map_foreign_page(unsigned long lpfn, unsigned long fgfn, unsigned int domid) { int rc; @@ -49,7 +49,7 @@ static int map_foreign_page(unsigned long lpfn, unsigned long fgmfn, .size = 1, .space = XENMAPSPACE_gmfn_foreign, }; - xen_ulong_t idx = fgmfn; + xen_ulong_t idx = fgfn; xen_pfn_t gpfn = lpfn; int err = 0; @@ -62,13 +62,13 @@ static int map_foreign_page(unsigned long lpfn, unsigned long fgmfn, } struct remap_data { - xen_pfn_t *fgmfn; /* foreign domain's gmfn */ + xen_pfn_t *fgfn; /* foreign domain's gfn */ pgprot_t prot; domid_t domid; struct vm_area_struct *vma; int index; struct page **pages; - struct xen_remap_mfn_info *info; + struct xen_remap_gfn_info *info; int *err_ptr; int mapped; }; @@ -82,20 +82,20 @@ static int remap_pte_fn(pte_t *ptep, pgtable_t token, unsigned long addr, pte_t pte = pte_mkspecial(pfn_pte(pfn, info->prot)); int rc; - rc = map_foreign_page(pfn, *info->fgmfn, info->domid); + rc = map_foreign_page(pfn, *info->fgfn, info->domid); *info->err_ptr++ = rc; if (!rc) { set_pte_at(info->vma->vm_mm, addr, ptep, pte); info->mapped++; } - info->fgmfn++; + info->fgfn++; return 0; } int xen_xlate_remap_gfn_array(struct vm_area_struct *vma, unsigned long addr, - xen_pfn_t *mfn, int nr, + xen_pfn_t *gfn, int nr, int *err_ptr, pgprot_t prot, unsigned domid, struct page **pages) @@ -108,7 +108,7 @@ int xen_xlate_remap_gfn_array(struct vm_area_struct *vma, x86 PVOPS */ BUG_ON(!((vma->vm_flags & (VM_PFNMAP | VM_IO)) == (VM_PFNMAP | VM_IO))); - data.fgmfn = mfn; + data.fgfn = gfn; data.prot = prot; data.domid = domid; data.vma = vma; 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