From 162e371712768248a38646eefa71af38b6e0f8ce Mon Sep 17 00:00:00 2001 From: David Vrabel Date: Fri, 11 Jul 2014 16:42:34 +0100 Subject: x86/xen: safely map and unmap grant frames when in atomic context arch_gnttab_map_frames() and arch_gnttab_unmap_frames() are called in atomic context but were calling alloc_vm_area() which might sleep. Also, if a driver attempts to allocate a grant ref from an interrupt and the table needs expanding, then the CPU may already by in lazy MMU mode and apply_to_page_range() will BUG when it tries to re-enable lazy MMU mode. These two functions are only used in PV guests. Introduce arch_gnttab_init() to allocates the virtual address space in advance. Avoid the use of apply_to_page_range() by using saving and using the array of PTE addresses from the alloc_vm_area() call. N.B. 'alloc_vm_area' pre-allocates the pagetable so there is no need to worry about having to do a PGD/PUD/PMD walk (like apply_to_page_range does) and we can instead do set_pte. Signed-off-by: David Vrabel Signed-off-by: Konrad Rzeszutek Wilk ---- [v2: Add comment about alloc_vm_area] [v3: Fix compile error found by 0-day bot] --- include/xen/grant_table.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/xen/grant_table.h b/include/xen/grant_table.h index a5af2a26d94f..5c1aba154b64 100644 --- a/include/xen/grant_table.h +++ b/include/xen/grant_table.h @@ -170,6 +170,7 @@ gnttab_set_unmap_op(struct gnttab_unmap_grant_ref *unmap, phys_addr_t addr, unmap->dev_bus_addr = 0; } +int arch_gnttab_init(unsigned long nr_shared, unsigned long nr_status); int arch_gnttab_map_shared(xen_pfn_t *frames, unsigned long nr_gframes, unsigned long max_nr_gframes, void **__shared); -- cgit v1.2.3 From 438b33c7145ca8a5131a30c36d8f59bce119a19a Mon Sep 17 00:00:00 2001 From: David Vrabel Date: Wed, 2 Jul 2014 11:25:29 +0100 Subject: xen/grant-table: remove support for V2 tables Since 11c7ff17c9b6dbf3a4e4f36be30ad531a6cf0ec9 (xen/grant-table: Force to use v1 of grants.) the code for V2 grant tables is not used. Signed-off-by: David Vrabel Signed-off-by: Konrad Rzeszutek Wilk --- include/xen/grant_table.h | 30 +----------------------------- 1 file changed, 1 insertion(+), 29 deletions(-) (limited to 'include') diff --git a/include/xen/grant_table.h b/include/xen/grant_table.h index 5c1aba154b64..3387465b9caa 100644 --- a/include/xen/grant_table.h +++ b/include/xen/grant_table.h @@ -64,24 +64,6 @@ int gnttab_resume(void); int gnttab_grant_foreign_access(domid_t domid, unsigned long frame, int readonly); -int gnttab_grant_foreign_access_subpage(domid_t domid, unsigned long frame, - int flags, unsigned page_off, - unsigned length); -int gnttab_grant_foreign_access_trans(domid_t domid, int flags, - domid_t trans_domid, - grant_ref_t trans_gref); - -/* - * Are sub-page grants available on this version of Xen? Returns true if they - * are, and false if they're not. - */ -bool gnttab_subpage_grants_available(void); - -/* - * Are transitive grants available on this version of Xen? Returns true if they - * are, and false if they're not. - */ -bool gnttab_trans_grants_available(void); /* * End access through the given grant reference, iff the grant entry is no @@ -128,13 +110,6 @@ void gnttab_cancel_free_callback(struct gnttab_free_callback *callback); void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid, unsigned long frame, int readonly); -int gnttab_grant_foreign_access_subpage_ref(grant_ref_t ref, domid_t domid, - unsigned long frame, int flags, - unsigned page_off, - unsigned length); -int gnttab_grant_foreign_access_trans_ref(grant_ref_t ref, domid_t domid, - int flags, domid_t trans_domid, - grant_ref_t trans_gref); void gnttab_grant_foreign_transfer_ref(grant_ref_t, domid_t domid, unsigned long pfn); @@ -170,13 +145,10 @@ gnttab_set_unmap_op(struct gnttab_unmap_grant_ref *unmap, phys_addr_t addr, unmap->dev_bus_addr = 0; } -int arch_gnttab_init(unsigned long nr_shared, unsigned long nr_status); +int arch_gnttab_init(unsigned long nr_shared); int arch_gnttab_map_shared(xen_pfn_t *frames, unsigned long nr_gframes, unsigned long max_nr_gframes, void **__shared); -int arch_gnttab_map_status(uint64_t *frames, unsigned long nr_gframes, - unsigned long max_nr_gframes, - grant_status_t **__shared); void arch_gnttab_unmap(void *shared, unsigned long nr_gframes); struct grant_frames { -- cgit v1.2.3