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diff --git a/include/xen/grant_table.h b/include/xen/grant_table.h
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+/******************************************************************************
+ * grant_table.h
+ *
+ * Two sets of functionality:
+ * 1. Granting foreign access to our memory reservation.
+ * 2. Accessing others' memory reservations via grant references.
+ * (i.e., mechanisms for both sender and recipient of grant references)
+ *
+ * Copyright (c) 2004-2005, K A Fraser
+ * Copyright (c) 2005, Christopher Clark
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#ifndef __ASM_GNTTAB_H__
+#define __ASM_GNTTAB_H__
+
+#include <asm/page.h>
+
+#include <xen/interface/xen.h>
+#include <xen/interface/grant_table.h>
+
+#include <asm/xen/hypervisor.h>
+
+#include <xen/features.h>
+#include <xen/page.h>
+#include <linux/mm_types.h>
+#include <linux/page-flags.h>
+#include <linux/kernel.h>
+
+#define GNTTAB_RESERVED_XENSTORE 1
+
+/* NR_GRANT_FRAMES must be less than or equal to that configured in Xen */
+#define NR_GRANT_FRAMES 4
+
+struct gnttab_free_callback {
+ struct gnttab_free_callback *next;
+ void (*fn)(void *);
+ void *arg;
+ u16 count;
+};
+
+struct gntab_unmap_queue_data;
+
+typedef void (*gnttab_unmap_refs_done)(int result, struct gntab_unmap_queue_data *data);
+
+struct gntab_unmap_queue_data
+{
+ struct delayed_work gnttab_work;
+ void *data;
+ gnttab_unmap_refs_done done;
+ struct gnttab_unmap_grant_ref *unmap_ops;
+ struct gnttab_unmap_grant_ref *kunmap_ops;
+ struct page **pages;
+ unsigned int count;
+ unsigned int age;
+};
+
+int gnttab_init(void);
+int gnttab_suspend(void);
+int gnttab_resume(void);
+
+int gnttab_grant_foreign_access(domid_t domid, unsigned long frame,
+ int readonly);
+
+/*
+ * End access through the given grant reference, iff the grant entry is no
+ * longer in use. Return 1 if the grant entry was freed, 0 if it is still in
+ * use.
+ */
+int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly);
+
+/*
+ * Eventually end access through the given grant reference, and once that
+ * access has been ended, free the given page too. Access will be ended
+ * immediately iff the grant entry is not in use, otherwise it will happen
+ * some time later. page may be 0, in which case no freeing will occur.
+ * Note that the granted page might still be accessed (read or write) by the
+ * other side after gnttab_end_foreign_access() returns, so even if page was
+ * specified as 0 it is not allowed to just reuse the page for other
+ * purposes immediately. gnttab_end_foreign_access() will take an additional
+ * reference to the granted page in this case, which is dropped only after
+ * the grant is no longer in use.
+ * This requires that multi page allocations for areas subject to
+ * gnttab_end_foreign_access() are done via alloc_pages_exact() (and freeing
+ * via free_pages_exact()) in order to avoid high order pages.
+ */
+void gnttab_end_foreign_access(grant_ref_t ref, int readonly,
+ unsigned long page);
+
+/*
+ * End access through the given grant reference, iff the grant entry is
+ * no longer in use. In case of success ending foreign access, the
+ * grant reference is deallocated.
+ * Return 1 if the grant entry was freed, 0 if it is still in use.
+ */
+int gnttab_try_end_foreign_access(grant_ref_t ref);
+
+int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn);
+
+unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref);
+unsigned long gnttab_end_foreign_transfer(grant_ref_t ref);
+
+/*
+ * operations on reserved batches of grant references
+ */
+int gnttab_alloc_grant_references(u16 count, grant_ref_t *pprivate_head);
+
+void gnttab_free_grant_reference(grant_ref_t ref);
+
+void gnttab_free_grant_references(grant_ref_t head);
+
+int gnttab_empty_grant_references(const grant_ref_t *pprivate_head);
+
+int gnttab_claim_grant_reference(grant_ref_t *pprivate_head);
+
+void gnttab_release_grant_reference(grant_ref_t *private_head,
+ grant_ref_t release);
+
+void gnttab_request_free_callback(struct gnttab_free_callback *callback,
+ void (*fn)(void *), void *arg, u16 count);
+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);
+
+/* Give access to the first 4K of the page */
+static inline void gnttab_page_grant_foreign_access_ref_one(
+ grant_ref_t ref, domid_t domid,
+ struct page *page, int readonly)
+{
+ gnttab_grant_foreign_access_ref(ref, domid, xen_page_to_gfn(page),
+ readonly);
+}
+
+void gnttab_grant_foreign_transfer_ref(grant_ref_t, domid_t domid,
+ unsigned long pfn);
+
+static inline void
+gnttab_set_map_op(struct gnttab_map_grant_ref *map, phys_addr_t addr,
+ uint32_t flags, grant_ref_t ref, domid_t domid)
+{
+ if (flags & GNTMAP_contains_pte)
+ map->host_addr = addr;
+ else if (xen_feature(XENFEAT_auto_translated_physmap))
+ map->host_addr = __pa(addr);
+ else
+ map->host_addr = addr;
+
+ map->flags = flags;
+ map->ref = ref;
+ map->dom = domid;
+ map->status = 1; /* arbitrary positive value */
+}
+
+static inline void
+gnttab_set_unmap_op(struct gnttab_unmap_grant_ref *unmap, phys_addr_t addr,
+ uint32_t flags, grant_handle_t handle)
+{
+ if (flags & GNTMAP_contains_pte)
+ unmap->host_addr = addr;
+ else if (xen_feature(XENFEAT_auto_translated_physmap))
+ unmap->host_addr = __pa(addr);
+ else
+ unmap->host_addr = addr;
+
+ unmap->handle = handle;
+ 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);
+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 {
+ xen_pfn_t *pfn;
+ unsigned int count;
+ void *vaddr;
+};
+extern struct grant_frames xen_auto_xlat_grant_frames;
+unsigned int gnttab_max_grant_frames(void);
+int gnttab_setup_auto_xlat_frames(phys_addr_t addr);
+void gnttab_free_auto_xlat_frames(void);
+
+#define gnttab_map_vaddr(map) ((void *)(map.host_virt_addr))
+
+int gnttab_alloc_pages(int nr_pages, struct page **pages);
+void gnttab_free_pages(int nr_pages, struct page **pages);
+
+struct gnttab_page_cache {
+ spinlock_t lock;
+#ifdef CONFIG_XEN_UNPOPULATED_ALLOC
+ struct page *pages;
+#else
+ struct list_head pages;
+#endif
+ unsigned int num_pages;
+};
+
+void gnttab_page_cache_init(struct gnttab_page_cache *cache);
+int gnttab_page_cache_get(struct gnttab_page_cache *cache, struct page **page);
+void gnttab_page_cache_put(struct gnttab_page_cache *cache, struct page **page,
+ unsigned int num);
+void gnttab_page_cache_shrink(struct gnttab_page_cache *cache,
+ unsigned int num);
+
+#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
+struct gnttab_dma_alloc_args {
+ /* Device for which DMA memory will be/was allocated. */
+ struct device *dev;
+ /* If set then DMA buffer is coherent and write-combine otherwise. */
+ bool coherent;
+
+ int nr_pages;
+ struct page **pages;
+ xen_pfn_t *frames;
+ void *vaddr;
+ dma_addr_t dev_bus_addr;
+};
+
+int gnttab_dma_alloc_pages(struct gnttab_dma_alloc_args *args);
+int gnttab_dma_free_pages(struct gnttab_dma_alloc_args *args);
+#endif
+
+int gnttab_pages_set_private(int nr_pages, struct page **pages);
+void gnttab_pages_clear_private(int nr_pages, struct page **pages);
+
+int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
+ struct gnttab_map_grant_ref *kmap_ops,
+ struct page **pages, unsigned int count);
+int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops,
+ struct gnttab_unmap_grant_ref *kunmap_ops,
+ struct page **pages, unsigned int count);
+void gnttab_unmap_refs_async(struct gntab_unmap_queue_data* item);
+int gnttab_unmap_refs_sync(struct gntab_unmap_queue_data *item);
+
+
+/* Perform a batch of grant map/copy operations. Retry every batch slot
+ * for which the hypervisor returns GNTST_eagain. This is typically due
+ * to paged out target frames.
+ *
+ * Will retry for 1, 2, ... 255 ms, i.e. 256 times during 32 seconds.
+ *
+ * Return value in each iand every status field of the batch guaranteed
+ * to not be GNTST_eagain.
+ */
+void gnttab_batch_map(struct gnttab_map_grant_ref *batch, unsigned count);
+void gnttab_batch_copy(struct gnttab_copy *batch, unsigned count);
+
+
+struct xen_page_foreign {
+ domid_t domid;
+ grant_ref_t gref;
+};
+
+static inline struct xen_page_foreign *xen_page_foreign(struct page *page)
+{
+ if (!PageForeign(page))
+ return NULL;
+#if BITS_PER_LONG < 64
+ return (struct xen_page_foreign *)page->private;
+#else
+ BUILD_BUG_ON(sizeof(struct xen_page_foreign) > BITS_PER_LONG);
+ return (struct xen_page_foreign *)&page->private;
+#endif
+}
+
+/* Split Linux page in chunk of the size of the grant and call fn
+ *
+ * Parameters of fn:
+ * gfn: guest frame number
+ * offset: offset in the grant
+ * len: length of the data in the grant.
+ * data: internal information
+ */
+typedef void (*xen_grant_fn_t)(unsigned long gfn, unsigned int offset,
+ unsigned int len, void *data);
+
+void gnttab_foreach_grant_in_range(struct page *page,
+ unsigned int offset,
+ unsigned int len,
+ xen_grant_fn_t fn,
+ void *data);
+
+/* Helper to get to call fn only on the first "grant chunk" */
+static inline void gnttab_for_one_grant(struct page *page, unsigned int offset,
+ unsigned len, xen_grant_fn_t fn,
+ void *data)
+{
+ /* The first request is limited to the size of one grant */
+ len = min_t(unsigned int, XEN_PAGE_SIZE - (offset & ~XEN_PAGE_MASK),
+ len);
+
+ gnttab_foreach_grant_in_range(page, offset, len, fn, data);
+}
+
+/* Get @nr_grefs grants from an array of page and call fn for each grant */
+void gnttab_foreach_grant(struct page **pages,
+ unsigned int nr_grefs,
+ xen_grant_fn_t fn,
+ void *data);
+
+/* Get the number of grant in a specified region
+ *
+ * start: Offset from the beginning of the first page
+ * len: total length of data (can cross multiple page)
+ */
+static inline unsigned int gnttab_count_grant(unsigned int start,
+ unsigned int len)
+{
+ return XEN_PFN_UP(xen_offset_in_page(start) + len);
+}
+
+#endif /* __ASM_GNTTAB_H__ */