1490 lines
38 KiB
C
1490 lines
38 KiB
C
/******************************************************************************
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* grant_table.c
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*
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* Granting foreign access to our memory reservation.
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*
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* Copyright (c) 2005-2006, Christopher Clark
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* Copyright (c) 2004-2005, K A Fraser
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License version 2
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* as published by the Free Software Foundation; or, when distributed
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* separately from the Linux kernel or incorporated into other
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* software packages, subject to the following license:
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this source file (the "Software"), to deal in the Software without
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* restriction, including without limitation the rights to use, copy, modify,
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* merge, publish, distribute, sublicense, and/or sell copies of the Software,
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* and to permit persons to whom the Software is furnished to do so, subject to
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* the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
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* IN THE SOFTWARE.
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*/
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#define pr_fmt(fmt) "xen:" KBUILD_MODNAME ": " fmt
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#include <linux/memblock.h>
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#include <linux/sched.h>
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#include <linux/mm.h>
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#include <linux/slab.h>
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#include <linux/vmalloc.h>
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#include <linux/uaccess.h>
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#include <linux/io.h>
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#include <linux/delay.h>
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#include <linux/hardirq.h>
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#include <linux/workqueue.h>
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#include <linux/ratelimit.h>
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#include <linux/moduleparam.h>
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#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
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#include <linux/dma-mapping.h>
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#endif
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#include <xen/xen.h>
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#include <xen/interface/xen.h>
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#include <xen/page.h>
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#include <xen/grant_table.h>
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#include <xen/interface/memory.h>
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#include <xen/hvc-console.h>
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#include <xen/swiotlb-xen.h>
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#include <xen/balloon.h>
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#ifdef CONFIG_X86
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#include <asm/xen/cpuid.h>
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#endif
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#include <xen/mem-reservation.h>
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#include <asm/xen/hypercall.h>
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#include <asm/xen/interface.h>
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#include <asm/pgtable.h>
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#include <asm/sync_bitops.h>
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/* External tools reserve first few grant table entries. */
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#define NR_RESERVED_ENTRIES 8
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#define GNTTAB_LIST_END 0xffffffff
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static grant_ref_t **gnttab_list;
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static unsigned int nr_grant_frames;
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static int gnttab_free_count;
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static grant_ref_t gnttab_free_head;
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static DEFINE_SPINLOCK(gnttab_list_lock);
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struct grant_frames xen_auto_xlat_grant_frames;
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static unsigned int xen_gnttab_version;
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module_param_named(version, xen_gnttab_version, uint, 0);
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static union {
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struct grant_entry_v1 *v1;
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union grant_entry_v2 *v2;
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void *addr;
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} gnttab_shared;
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/*This is a structure of function pointers for grant table*/
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struct gnttab_ops {
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/*
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* Version of the grant interface.
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*/
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unsigned int version;
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/*
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* Grant refs per grant frame.
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*/
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unsigned int grefs_per_grant_frame;
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/*
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* Mapping a list of frames for storing grant entries. Frames parameter
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* is used to store grant table address when grant table being setup,
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* nr_gframes is the number of frames to map grant table. Returning
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* GNTST_okay means success and negative value means failure.
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*/
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int (*map_frames)(xen_pfn_t *frames, unsigned int nr_gframes);
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/*
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* Release a list of frames which are mapped in map_frames for grant
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* entry status.
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*/
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void (*unmap_frames)(void);
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/*
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* Introducing a valid entry into the grant table, granting the frame of
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* this grant entry to domain for accessing or transfering. Ref
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* parameter is reference of this introduced grant entry, domid is id of
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* granted domain, frame is the page frame to be granted, and flags is
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* status of the grant entry to be updated.
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*/
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void (*update_entry)(grant_ref_t ref, domid_t domid,
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unsigned long frame, unsigned flags);
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/*
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* Stop granting a grant entry to domain for accessing. Ref parameter is
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* reference of a grant entry whose grant access will be stopped,
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* readonly is not in use in this function. If the grant entry is
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* currently mapped for reading or writing, just return failure(==0)
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* directly and don't tear down the grant access. Otherwise, stop grant
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* access for this entry and return success(==1).
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*/
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int (*end_foreign_access_ref)(grant_ref_t ref, int readonly);
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/*
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* Stop granting a grant entry to domain for transfer. Ref parameter is
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* reference of a grant entry whose grant transfer will be stopped. If
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* tranfer has not started, just reclaim the grant entry and return
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* failure(==0). Otherwise, wait for the transfer to complete and then
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* return the frame.
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*/
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unsigned long (*end_foreign_transfer_ref)(grant_ref_t ref);
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/*
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* Query the status of a grant entry. Ref parameter is reference of
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* queried grant entry, return value is the status of queried entry.
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* Detailed status(writing/reading) can be gotten from the return value
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* by bit operations.
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*/
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int (*query_foreign_access)(grant_ref_t ref);
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};
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struct unmap_refs_callback_data {
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struct completion completion;
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int result;
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};
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static const struct gnttab_ops *gnttab_interface;
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/* This reflects status of grant entries, so act as a global value. */
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static grant_status_t *grstatus;
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static struct gnttab_free_callback *gnttab_free_callback_list;
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static int gnttab_expand(unsigned int req_entries);
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#define RPP (PAGE_SIZE / sizeof(grant_ref_t))
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#define SPP (PAGE_SIZE / sizeof(grant_status_t))
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static inline grant_ref_t *__gnttab_entry(grant_ref_t entry)
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{
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return &gnttab_list[(entry) / RPP][(entry) % RPP];
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}
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/* This can be used as an l-value */
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#define gnttab_entry(entry) (*__gnttab_entry(entry))
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static int get_free_entries(unsigned count)
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{
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unsigned long flags;
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int ref, rc = 0;
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grant_ref_t head;
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spin_lock_irqsave(&gnttab_list_lock, flags);
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if ((gnttab_free_count < count) &&
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((rc = gnttab_expand(count - gnttab_free_count)) < 0)) {
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spin_unlock_irqrestore(&gnttab_list_lock, flags);
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return rc;
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}
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ref = head = gnttab_free_head;
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gnttab_free_count -= count;
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while (count-- > 1)
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head = gnttab_entry(head);
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gnttab_free_head = gnttab_entry(head);
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gnttab_entry(head) = GNTTAB_LIST_END;
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spin_unlock_irqrestore(&gnttab_list_lock, flags);
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return ref;
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}
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static void do_free_callbacks(void)
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{
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struct gnttab_free_callback *callback, *next;
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callback = gnttab_free_callback_list;
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gnttab_free_callback_list = NULL;
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while (callback != NULL) {
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next = callback->next;
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if (gnttab_free_count >= callback->count) {
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callback->next = NULL;
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callback->fn(callback->arg);
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} else {
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callback->next = gnttab_free_callback_list;
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gnttab_free_callback_list = callback;
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}
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callback = next;
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}
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}
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static inline void check_free_callbacks(void)
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{
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if (unlikely(gnttab_free_callback_list))
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do_free_callbacks();
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}
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static void put_free_entry(grant_ref_t ref)
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{
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unsigned long flags;
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spin_lock_irqsave(&gnttab_list_lock, flags);
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gnttab_entry(ref) = gnttab_free_head;
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gnttab_free_head = ref;
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gnttab_free_count++;
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check_free_callbacks();
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spin_unlock_irqrestore(&gnttab_list_lock, flags);
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}
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/*
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* Following applies to gnttab_update_entry_v1 and gnttab_update_entry_v2.
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* Introducing a valid entry into the grant table:
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* 1. Write ent->domid.
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* 2. Write ent->frame:
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* GTF_permit_access: Frame to which access is permitted.
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* GTF_accept_transfer: Pseudo-phys frame slot being filled by new
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* frame, or zero if none.
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* 3. Write memory barrier (WMB).
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* 4. Write ent->flags, inc. valid type.
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*/
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static void gnttab_update_entry_v1(grant_ref_t ref, domid_t domid,
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unsigned long frame, unsigned flags)
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{
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gnttab_shared.v1[ref].domid = domid;
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gnttab_shared.v1[ref].frame = frame;
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wmb();
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gnttab_shared.v1[ref].flags = flags;
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}
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static void gnttab_update_entry_v2(grant_ref_t ref, domid_t domid,
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unsigned long frame, unsigned int flags)
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{
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gnttab_shared.v2[ref].hdr.domid = domid;
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gnttab_shared.v2[ref].full_page.frame = frame;
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wmb(); /* Hypervisor concurrent accesses. */
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gnttab_shared.v2[ref].hdr.flags = GTF_permit_access | flags;
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}
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/*
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* Public grant-issuing interface functions
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*/
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void gnttab_grant_foreign_access_ref(grant_ref_t ref, domid_t domid,
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unsigned long frame, int readonly)
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{
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gnttab_interface->update_entry(ref, domid, frame,
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GTF_permit_access | (readonly ? GTF_readonly : 0));
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}
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EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access_ref);
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int gnttab_grant_foreign_access(domid_t domid, unsigned long frame,
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int readonly)
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{
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int ref;
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ref = get_free_entries(1);
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if (unlikely(ref < 0))
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return -ENOSPC;
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gnttab_grant_foreign_access_ref(ref, domid, frame, readonly);
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return ref;
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}
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EXPORT_SYMBOL_GPL(gnttab_grant_foreign_access);
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static int gnttab_query_foreign_access_v1(grant_ref_t ref)
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{
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return gnttab_shared.v1[ref].flags & (GTF_reading|GTF_writing);
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}
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static int gnttab_query_foreign_access_v2(grant_ref_t ref)
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{
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return grstatus[ref] & (GTF_reading|GTF_writing);
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}
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int gnttab_query_foreign_access(grant_ref_t ref)
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{
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return gnttab_interface->query_foreign_access(ref);
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}
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EXPORT_SYMBOL_GPL(gnttab_query_foreign_access);
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static int gnttab_end_foreign_access_ref_v1(grant_ref_t ref, int readonly)
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{
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u16 flags, nflags;
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u16 *pflags;
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pflags = &gnttab_shared.v1[ref].flags;
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nflags = *pflags;
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do {
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flags = nflags;
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if (flags & (GTF_reading|GTF_writing))
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return 0;
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} while ((nflags = sync_cmpxchg(pflags, flags, 0)) != flags);
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return 1;
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}
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static int gnttab_end_foreign_access_ref_v2(grant_ref_t ref, int readonly)
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{
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gnttab_shared.v2[ref].hdr.flags = 0;
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mb(); /* Concurrent access by hypervisor. */
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if (grstatus[ref] & (GTF_reading|GTF_writing)) {
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return 0;
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} else {
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/*
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* The read of grstatus needs to have acquire semantics.
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* On x86, reads already have that, and we just need to
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* protect against compiler reorderings.
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* On other architectures we may need a full barrier.
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*/
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#ifdef CONFIG_X86
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barrier();
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#else
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mb();
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#endif
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}
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return 1;
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}
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static inline int _gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly)
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{
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return gnttab_interface->end_foreign_access_ref(ref, readonly);
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}
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int gnttab_end_foreign_access_ref(grant_ref_t ref, int readonly)
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{
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if (_gnttab_end_foreign_access_ref(ref, readonly))
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return 1;
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pr_warn("WARNING: g.e. %#x still in use!\n", ref);
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return 0;
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}
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EXPORT_SYMBOL_GPL(gnttab_end_foreign_access_ref);
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struct deferred_entry {
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struct list_head list;
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grant_ref_t ref;
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bool ro;
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uint16_t warn_delay;
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struct page *page;
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};
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static LIST_HEAD(deferred_list);
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static void gnttab_handle_deferred(struct timer_list *);
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static DEFINE_TIMER(deferred_timer, gnttab_handle_deferred);
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static void gnttab_handle_deferred(struct timer_list *unused)
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{
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unsigned int nr = 10;
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struct deferred_entry *first = NULL;
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unsigned long flags;
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spin_lock_irqsave(&gnttab_list_lock, flags);
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while (nr--) {
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struct deferred_entry *entry
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= list_first_entry(&deferred_list,
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struct deferred_entry, list);
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if (entry == first)
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break;
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list_del(&entry->list);
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spin_unlock_irqrestore(&gnttab_list_lock, flags);
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if (_gnttab_end_foreign_access_ref(entry->ref, entry->ro)) {
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put_free_entry(entry->ref);
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if (entry->page) {
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pr_debug("freeing g.e. %#x (pfn %#lx)\n",
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entry->ref, page_to_pfn(entry->page));
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put_page(entry->page);
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} else
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pr_info("freeing g.e. %#x\n", entry->ref);
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kfree(entry);
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entry = NULL;
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} else {
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if (!--entry->warn_delay)
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pr_info("g.e. %#x still pending\n", entry->ref);
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if (!first)
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first = entry;
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}
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spin_lock_irqsave(&gnttab_list_lock, flags);
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if (entry)
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list_add_tail(&entry->list, &deferred_list);
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else if (list_empty(&deferred_list))
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break;
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}
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if (!list_empty(&deferred_list) && !timer_pending(&deferred_timer)) {
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deferred_timer.expires = jiffies + HZ;
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add_timer(&deferred_timer);
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}
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spin_unlock_irqrestore(&gnttab_list_lock, flags);
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}
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static void gnttab_add_deferred(grant_ref_t ref, bool readonly,
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struct page *page)
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{
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struct deferred_entry *entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
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const char *what = KERN_WARNING "leaking";
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if (entry) {
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unsigned long flags;
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entry->ref = ref;
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entry->ro = readonly;
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entry->page = page;
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entry->warn_delay = 60;
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spin_lock_irqsave(&gnttab_list_lock, flags);
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list_add_tail(&entry->list, &deferred_list);
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if (!timer_pending(&deferred_timer)) {
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deferred_timer.expires = jiffies + HZ;
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add_timer(&deferred_timer);
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}
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spin_unlock_irqrestore(&gnttab_list_lock, flags);
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what = KERN_DEBUG "deferring";
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}
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printk("%s g.e. %#x (pfn %#lx)\n",
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what, ref, page ? page_to_pfn(page) : -1);
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}
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void gnttab_end_foreign_access(grant_ref_t ref, int readonly,
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unsigned long page)
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{
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if (gnttab_end_foreign_access_ref(ref, readonly)) {
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put_free_entry(ref);
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if (page != 0)
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put_page(virt_to_page(page));
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} else
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gnttab_add_deferred(ref, readonly,
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page ? virt_to_page(page) : NULL);
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}
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EXPORT_SYMBOL_GPL(gnttab_end_foreign_access);
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int gnttab_grant_foreign_transfer(domid_t domid, unsigned long pfn)
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{
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int ref;
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ref = get_free_entries(1);
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if (unlikely(ref < 0))
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return -ENOSPC;
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gnttab_grant_foreign_transfer_ref(ref, domid, pfn);
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return ref;
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}
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EXPORT_SYMBOL_GPL(gnttab_grant_foreign_transfer);
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void gnttab_grant_foreign_transfer_ref(grant_ref_t ref, domid_t domid,
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unsigned long pfn)
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{
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gnttab_interface->update_entry(ref, domid, pfn, GTF_accept_transfer);
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}
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EXPORT_SYMBOL_GPL(gnttab_grant_foreign_transfer_ref);
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static unsigned long gnttab_end_foreign_transfer_ref_v1(grant_ref_t ref)
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{
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unsigned long frame;
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u16 flags;
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u16 *pflags;
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pflags = &gnttab_shared.v1[ref].flags;
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/*
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* If a transfer is not even yet started, try to reclaim the grant
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* reference and return failure (== 0).
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*/
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while (!((flags = *pflags) & GTF_transfer_committed)) {
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if (sync_cmpxchg(pflags, flags, 0) == flags)
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return 0;
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cpu_relax();
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}
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/* If a transfer is in progress then wait until it is completed. */
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while (!(flags & GTF_transfer_completed)) {
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flags = *pflags;
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cpu_relax();
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}
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rmb(); /* Read the frame number /after/ reading completion status. */
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frame = gnttab_shared.v1[ref].frame;
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BUG_ON(frame == 0);
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return frame;
|
|
}
|
|
|
|
static unsigned long gnttab_end_foreign_transfer_ref_v2(grant_ref_t ref)
|
|
{
|
|
unsigned long frame;
|
|
u16 flags;
|
|
u16 *pflags;
|
|
|
|
pflags = &gnttab_shared.v2[ref].hdr.flags;
|
|
|
|
/*
|
|
* If a transfer is not even yet started, try to reclaim the grant
|
|
* reference and return failure (== 0).
|
|
*/
|
|
while (!((flags = *pflags) & GTF_transfer_committed)) {
|
|
if (sync_cmpxchg(pflags, flags, 0) == flags)
|
|
return 0;
|
|
cpu_relax();
|
|
}
|
|
|
|
/* If a transfer is in progress then wait until it is completed. */
|
|
while (!(flags & GTF_transfer_completed)) {
|
|
flags = *pflags;
|
|
cpu_relax();
|
|
}
|
|
|
|
rmb(); /* Read the frame number /after/ reading completion status. */
|
|
frame = gnttab_shared.v2[ref].full_page.frame;
|
|
BUG_ON(frame == 0);
|
|
|
|
return frame;
|
|
}
|
|
|
|
unsigned long gnttab_end_foreign_transfer_ref(grant_ref_t ref)
|
|
{
|
|
return gnttab_interface->end_foreign_transfer_ref(ref);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_end_foreign_transfer_ref);
|
|
|
|
unsigned long gnttab_end_foreign_transfer(grant_ref_t ref)
|
|
{
|
|
unsigned long frame = gnttab_end_foreign_transfer_ref(ref);
|
|
put_free_entry(ref);
|
|
return frame;
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_end_foreign_transfer);
|
|
|
|
void gnttab_free_grant_reference(grant_ref_t ref)
|
|
{
|
|
put_free_entry(ref);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_free_grant_reference);
|
|
|
|
void gnttab_free_grant_references(grant_ref_t head)
|
|
{
|
|
grant_ref_t ref;
|
|
unsigned long flags;
|
|
int count = 1;
|
|
if (head == GNTTAB_LIST_END)
|
|
return;
|
|
spin_lock_irqsave(&gnttab_list_lock, flags);
|
|
ref = head;
|
|
while (gnttab_entry(ref) != GNTTAB_LIST_END) {
|
|
ref = gnttab_entry(ref);
|
|
count++;
|
|
}
|
|
gnttab_entry(ref) = gnttab_free_head;
|
|
gnttab_free_head = head;
|
|
gnttab_free_count += count;
|
|
check_free_callbacks();
|
|
spin_unlock_irqrestore(&gnttab_list_lock, flags);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_free_grant_references);
|
|
|
|
int gnttab_alloc_grant_references(u16 count, grant_ref_t *head)
|
|
{
|
|
int h = get_free_entries(count);
|
|
|
|
if (h < 0)
|
|
return -ENOSPC;
|
|
|
|
*head = h;
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_alloc_grant_references);
|
|
|
|
int gnttab_empty_grant_references(const grant_ref_t *private_head)
|
|
{
|
|
return (*private_head == GNTTAB_LIST_END);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_empty_grant_references);
|
|
|
|
int gnttab_claim_grant_reference(grant_ref_t *private_head)
|
|
{
|
|
grant_ref_t g = *private_head;
|
|
if (unlikely(g == GNTTAB_LIST_END))
|
|
return -ENOSPC;
|
|
*private_head = gnttab_entry(g);
|
|
return g;
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_claim_grant_reference);
|
|
|
|
void gnttab_release_grant_reference(grant_ref_t *private_head,
|
|
grant_ref_t release)
|
|
{
|
|
gnttab_entry(release) = *private_head;
|
|
*private_head = release;
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_release_grant_reference);
|
|
|
|
void gnttab_request_free_callback(struct gnttab_free_callback *callback,
|
|
void (*fn)(void *), void *arg, u16 count)
|
|
{
|
|
unsigned long flags;
|
|
struct gnttab_free_callback *cb;
|
|
|
|
spin_lock_irqsave(&gnttab_list_lock, flags);
|
|
|
|
/* Check if the callback is already on the list */
|
|
cb = gnttab_free_callback_list;
|
|
while (cb) {
|
|
if (cb == callback)
|
|
goto out;
|
|
cb = cb->next;
|
|
}
|
|
|
|
callback->fn = fn;
|
|
callback->arg = arg;
|
|
callback->count = count;
|
|
callback->next = gnttab_free_callback_list;
|
|
gnttab_free_callback_list = callback;
|
|
check_free_callbacks();
|
|
out:
|
|
spin_unlock_irqrestore(&gnttab_list_lock, flags);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_request_free_callback);
|
|
|
|
void gnttab_cancel_free_callback(struct gnttab_free_callback *callback)
|
|
{
|
|
struct gnttab_free_callback **pcb;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&gnttab_list_lock, flags);
|
|
for (pcb = &gnttab_free_callback_list; *pcb; pcb = &(*pcb)->next) {
|
|
if (*pcb == callback) {
|
|
*pcb = callback->next;
|
|
break;
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&gnttab_list_lock, flags);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_cancel_free_callback);
|
|
|
|
static unsigned int gnttab_frames(unsigned int frames, unsigned int align)
|
|
{
|
|
return (frames * gnttab_interface->grefs_per_grant_frame + align - 1) /
|
|
align;
|
|
}
|
|
|
|
static int grow_gnttab_list(unsigned int more_frames)
|
|
{
|
|
unsigned int new_nr_grant_frames, extra_entries, i;
|
|
unsigned int nr_glist_frames, new_nr_glist_frames;
|
|
unsigned int grefs_per_frame;
|
|
|
|
BUG_ON(gnttab_interface == NULL);
|
|
grefs_per_frame = gnttab_interface->grefs_per_grant_frame;
|
|
|
|
new_nr_grant_frames = nr_grant_frames + more_frames;
|
|
extra_entries = more_frames * grefs_per_frame;
|
|
|
|
nr_glist_frames = gnttab_frames(nr_grant_frames, RPP);
|
|
new_nr_glist_frames = gnttab_frames(new_nr_grant_frames, RPP);
|
|
for (i = nr_glist_frames; i < new_nr_glist_frames; i++) {
|
|
gnttab_list[i] = (grant_ref_t *)__get_free_page(GFP_ATOMIC);
|
|
if (!gnttab_list[i])
|
|
goto grow_nomem;
|
|
}
|
|
|
|
|
|
for (i = grefs_per_frame * nr_grant_frames;
|
|
i < grefs_per_frame * new_nr_grant_frames - 1; i++)
|
|
gnttab_entry(i) = i + 1;
|
|
|
|
gnttab_entry(i) = gnttab_free_head;
|
|
gnttab_free_head = grefs_per_frame * nr_grant_frames;
|
|
gnttab_free_count += extra_entries;
|
|
|
|
nr_grant_frames = new_nr_grant_frames;
|
|
|
|
check_free_callbacks();
|
|
|
|
return 0;
|
|
|
|
grow_nomem:
|
|
while (i-- > nr_glist_frames)
|
|
free_page((unsigned long) gnttab_list[i]);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static unsigned int __max_nr_grant_frames(void)
|
|
{
|
|
struct gnttab_query_size query;
|
|
int rc;
|
|
|
|
query.dom = DOMID_SELF;
|
|
|
|
rc = HYPERVISOR_grant_table_op(GNTTABOP_query_size, &query, 1);
|
|
if ((rc < 0) || (query.status != GNTST_okay))
|
|
return 4; /* Legacy max supported number of frames */
|
|
|
|
return query.max_nr_frames;
|
|
}
|
|
|
|
unsigned int gnttab_max_grant_frames(void)
|
|
{
|
|
unsigned int xen_max = __max_nr_grant_frames();
|
|
static unsigned int boot_max_nr_grant_frames;
|
|
|
|
/* First time, initialize it properly. */
|
|
if (!boot_max_nr_grant_frames)
|
|
boot_max_nr_grant_frames = __max_nr_grant_frames();
|
|
|
|
if (xen_max > boot_max_nr_grant_frames)
|
|
return boot_max_nr_grant_frames;
|
|
return xen_max;
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_max_grant_frames);
|
|
|
|
int gnttab_setup_auto_xlat_frames(phys_addr_t addr)
|
|
{
|
|
xen_pfn_t *pfn;
|
|
unsigned int max_nr_gframes = __max_nr_grant_frames();
|
|
unsigned int i;
|
|
void *vaddr;
|
|
|
|
if (xen_auto_xlat_grant_frames.count)
|
|
return -EINVAL;
|
|
|
|
vaddr = xen_remap(addr, XEN_PAGE_SIZE * max_nr_gframes);
|
|
if (vaddr == NULL) {
|
|
pr_warn("Failed to ioremap gnttab share frames (addr=%pa)!\n",
|
|
&addr);
|
|
return -ENOMEM;
|
|
}
|
|
pfn = kcalloc(max_nr_gframes, sizeof(pfn[0]), GFP_KERNEL);
|
|
if (!pfn) {
|
|
xen_unmap(vaddr);
|
|
return -ENOMEM;
|
|
}
|
|
for (i = 0; i < max_nr_gframes; i++)
|
|
pfn[i] = XEN_PFN_DOWN(addr) + i;
|
|
|
|
xen_auto_xlat_grant_frames.vaddr = vaddr;
|
|
xen_auto_xlat_grant_frames.pfn = pfn;
|
|
xen_auto_xlat_grant_frames.count = max_nr_gframes;
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_setup_auto_xlat_frames);
|
|
|
|
void gnttab_free_auto_xlat_frames(void)
|
|
{
|
|
if (!xen_auto_xlat_grant_frames.count)
|
|
return;
|
|
kfree(xen_auto_xlat_grant_frames.pfn);
|
|
xen_unmap(xen_auto_xlat_grant_frames.vaddr);
|
|
|
|
xen_auto_xlat_grant_frames.pfn = NULL;
|
|
xen_auto_xlat_grant_frames.count = 0;
|
|
xen_auto_xlat_grant_frames.vaddr = NULL;
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_free_auto_xlat_frames);
|
|
|
|
int gnttab_pages_set_private(int nr_pages, struct page **pages)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < nr_pages; i++) {
|
|
#if BITS_PER_LONG < 64
|
|
struct xen_page_foreign *foreign;
|
|
|
|
foreign = kzalloc(sizeof(*foreign), GFP_KERNEL);
|
|
if (!foreign)
|
|
return -ENOMEM;
|
|
|
|
set_page_private(pages[i], (unsigned long)foreign);
|
|
#endif
|
|
SetPagePrivate(pages[i]);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_pages_set_private);
|
|
|
|
/**
|
|
* gnttab_alloc_pages - alloc pages suitable for grant mapping into
|
|
* @nr_pages: number of pages to alloc
|
|
* @pages: returns the pages
|
|
*/
|
|
int gnttab_alloc_pages(int nr_pages, struct page **pages)
|
|
{
|
|
int ret;
|
|
|
|
ret = alloc_xenballooned_pages(nr_pages, pages);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
ret = gnttab_pages_set_private(nr_pages, pages);
|
|
if (ret < 0)
|
|
gnttab_free_pages(nr_pages, pages);
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_alloc_pages);
|
|
|
|
void gnttab_pages_clear_private(int nr_pages, struct page **pages)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < nr_pages; i++) {
|
|
if (PagePrivate(pages[i])) {
|
|
#if BITS_PER_LONG < 64
|
|
kfree((void *)page_private(pages[i]));
|
|
#endif
|
|
ClearPagePrivate(pages[i]);
|
|
}
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_pages_clear_private);
|
|
|
|
/**
|
|
* gnttab_free_pages - free pages allocated by gnttab_alloc_pages()
|
|
* @nr_pages; number of pages to free
|
|
* @pages: the pages
|
|
*/
|
|
void gnttab_free_pages(int nr_pages, struct page **pages)
|
|
{
|
|
gnttab_pages_clear_private(nr_pages, pages);
|
|
free_xenballooned_pages(nr_pages, pages);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_free_pages);
|
|
|
|
#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
|
|
/**
|
|
* gnttab_dma_alloc_pages - alloc DMAable pages suitable for grant mapping into
|
|
* @args: arguments to the function
|
|
*/
|
|
int gnttab_dma_alloc_pages(struct gnttab_dma_alloc_args *args)
|
|
{
|
|
unsigned long pfn, start_pfn;
|
|
size_t size;
|
|
int i, ret;
|
|
|
|
size = args->nr_pages << PAGE_SHIFT;
|
|
if (args->coherent)
|
|
args->vaddr = dma_alloc_coherent(args->dev, size,
|
|
&args->dev_bus_addr,
|
|
GFP_KERNEL | __GFP_NOWARN);
|
|
else
|
|
args->vaddr = dma_alloc_wc(args->dev, size,
|
|
&args->dev_bus_addr,
|
|
GFP_KERNEL | __GFP_NOWARN);
|
|
if (!args->vaddr) {
|
|
pr_debug("Failed to allocate DMA buffer of size %zu\n", size);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
start_pfn = __phys_to_pfn(args->dev_bus_addr);
|
|
for (pfn = start_pfn, i = 0; pfn < start_pfn + args->nr_pages;
|
|
pfn++, i++) {
|
|
struct page *page = pfn_to_page(pfn);
|
|
|
|
args->pages[i] = page;
|
|
args->frames[i] = xen_page_to_gfn(page);
|
|
xenmem_reservation_scrub_page(page);
|
|
}
|
|
|
|
xenmem_reservation_va_mapping_reset(args->nr_pages, args->pages);
|
|
|
|
ret = xenmem_reservation_decrease(args->nr_pages, args->frames);
|
|
if (ret != args->nr_pages) {
|
|
pr_debug("Failed to decrease reservation for DMA buffer\n");
|
|
ret = -EFAULT;
|
|
goto fail;
|
|
}
|
|
|
|
ret = gnttab_pages_set_private(args->nr_pages, args->pages);
|
|
if (ret < 0)
|
|
goto fail;
|
|
|
|
return 0;
|
|
|
|
fail:
|
|
gnttab_dma_free_pages(args);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_dma_alloc_pages);
|
|
|
|
/**
|
|
* gnttab_dma_free_pages - free DMAable pages
|
|
* @args: arguments to the function
|
|
*/
|
|
int gnttab_dma_free_pages(struct gnttab_dma_alloc_args *args)
|
|
{
|
|
size_t size;
|
|
int i, ret;
|
|
|
|
gnttab_pages_clear_private(args->nr_pages, args->pages);
|
|
|
|
for (i = 0; i < args->nr_pages; i++)
|
|
args->frames[i] = page_to_xen_pfn(args->pages[i]);
|
|
|
|
ret = xenmem_reservation_increase(args->nr_pages, args->frames);
|
|
if (ret != args->nr_pages) {
|
|
pr_debug("Failed to increase reservation for DMA buffer\n");
|
|
ret = -EFAULT;
|
|
} else {
|
|
ret = 0;
|
|
}
|
|
|
|
xenmem_reservation_va_mapping_update(args->nr_pages, args->pages,
|
|
args->frames);
|
|
|
|
size = args->nr_pages << PAGE_SHIFT;
|
|
if (args->coherent)
|
|
dma_free_coherent(args->dev, size,
|
|
args->vaddr, args->dev_bus_addr);
|
|
else
|
|
dma_free_wc(args->dev, size,
|
|
args->vaddr, args->dev_bus_addr);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_dma_free_pages);
|
|
#endif
|
|
|
|
/* Handling of paged out grant targets (GNTST_eagain) */
|
|
#define MAX_DELAY 256
|
|
static inline void
|
|
gnttab_retry_eagain_gop(unsigned int cmd, void *gop, int16_t *status,
|
|
const char *func)
|
|
{
|
|
unsigned delay = 1;
|
|
|
|
do {
|
|
BUG_ON(HYPERVISOR_grant_table_op(cmd, gop, 1));
|
|
if (*status == GNTST_eagain)
|
|
msleep(delay++);
|
|
} while ((*status == GNTST_eagain) && (delay < MAX_DELAY));
|
|
|
|
if (delay >= MAX_DELAY) {
|
|
pr_err("%s: %s eagain grant\n", func, current->comm);
|
|
*status = GNTST_bad_page;
|
|
}
|
|
}
|
|
|
|
void gnttab_batch_map(struct gnttab_map_grant_ref *batch, unsigned count)
|
|
{
|
|
struct gnttab_map_grant_ref *op;
|
|
|
|
if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, batch, count))
|
|
BUG();
|
|
for (op = batch; op < batch + count; op++)
|
|
if (op->status == GNTST_eagain)
|
|
gnttab_retry_eagain_gop(GNTTABOP_map_grant_ref, op,
|
|
&op->status, __func__);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_batch_map);
|
|
|
|
void gnttab_batch_copy(struct gnttab_copy *batch, unsigned count)
|
|
{
|
|
struct gnttab_copy *op;
|
|
|
|
if (HYPERVISOR_grant_table_op(GNTTABOP_copy, batch, count))
|
|
BUG();
|
|
for (op = batch; op < batch + count; op++)
|
|
if (op->status == GNTST_eagain)
|
|
gnttab_retry_eagain_gop(GNTTABOP_copy, op,
|
|
&op->status, __func__);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_batch_copy);
|
|
|
|
void gnttab_foreach_grant_in_range(struct page *page,
|
|
unsigned int offset,
|
|
unsigned int len,
|
|
xen_grant_fn_t fn,
|
|
void *data)
|
|
{
|
|
unsigned int goffset;
|
|
unsigned int glen;
|
|
unsigned long xen_pfn;
|
|
|
|
len = min_t(unsigned int, PAGE_SIZE - offset, len);
|
|
goffset = xen_offset_in_page(offset);
|
|
|
|
xen_pfn = page_to_xen_pfn(page) + XEN_PFN_DOWN(offset);
|
|
|
|
while (len) {
|
|
glen = min_t(unsigned int, XEN_PAGE_SIZE - goffset, len);
|
|
fn(pfn_to_gfn(xen_pfn), goffset, glen, data);
|
|
|
|
goffset = 0;
|
|
xen_pfn++;
|
|
len -= glen;
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_foreach_grant_in_range);
|
|
|
|
void gnttab_foreach_grant(struct page **pages,
|
|
unsigned int nr_grefs,
|
|
xen_grant_fn_t fn,
|
|
void *data)
|
|
{
|
|
unsigned int goffset = 0;
|
|
unsigned long xen_pfn = 0;
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < nr_grefs; i++) {
|
|
if ((i % XEN_PFN_PER_PAGE) == 0) {
|
|
xen_pfn = page_to_xen_pfn(pages[i / XEN_PFN_PER_PAGE]);
|
|
goffset = 0;
|
|
}
|
|
|
|
fn(pfn_to_gfn(xen_pfn), goffset, XEN_PAGE_SIZE, data);
|
|
|
|
goffset += XEN_PAGE_SIZE;
|
|
xen_pfn++;
|
|
}
|
|
}
|
|
|
|
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 i, ret;
|
|
|
|
ret = HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, map_ops, count);
|
|
if (ret)
|
|
return ret;
|
|
|
|
for (i = 0; i < count; i++) {
|
|
switch (map_ops[i].status) {
|
|
case GNTST_okay:
|
|
{
|
|
struct xen_page_foreign *foreign;
|
|
|
|
SetPageForeign(pages[i]);
|
|
foreign = xen_page_foreign(pages[i]);
|
|
foreign->domid = map_ops[i].dom;
|
|
foreign->gref = map_ops[i].ref;
|
|
break;
|
|
}
|
|
|
|
case GNTST_no_device_space:
|
|
pr_warn_ratelimited("maptrack limit reached, can't map all guest pages\n");
|
|
break;
|
|
|
|
case GNTST_eagain:
|
|
/* Retry eagain maps */
|
|
gnttab_retry_eagain_gop(GNTTABOP_map_grant_ref,
|
|
map_ops + i,
|
|
&map_ops[i].status, __func__);
|
|
/* Test status in next loop iteration. */
|
|
i--;
|
|
break;
|
|
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
return set_foreign_p2m_mapping(map_ops, kmap_ops, pages, count);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_map_refs);
|
|
|
|
int gnttab_unmap_refs(struct gnttab_unmap_grant_ref *unmap_ops,
|
|
struct gnttab_unmap_grant_ref *kunmap_ops,
|
|
struct page **pages, unsigned int count)
|
|
{
|
|
unsigned int i;
|
|
int ret;
|
|
|
|
ret = HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, unmap_ops, count);
|
|
if (ret)
|
|
return ret;
|
|
|
|
for (i = 0; i < count; i++)
|
|
ClearPageForeign(pages[i]);
|
|
|
|
return clear_foreign_p2m_mapping(unmap_ops, kunmap_ops, pages, count);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_unmap_refs);
|
|
|
|
#define GNTTAB_UNMAP_REFS_DELAY 5
|
|
|
|
static void __gnttab_unmap_refs_async(struct gntab_unmap_queue_data* item);
|
|
|
|
static void gnttab_unmap_work(struct work_struct *work)
|
|
{
|
|
struct gntab_unmap_queue_data
|
|
*unmap_data = container_of(work,
|
|
struct gntab_unmap_queue_data,
|
|
gnttab_work.work);
|
|
if (unmap_data->age != UINT_MAX)
|
|
unmap_data->age++;
|
|
__gnttab_unmap_refs_async(unmap_data);
|
|
}
|
|
|
|
static void __gnttab_unmap_refs_async(struct gntab_unmap_queue_data* item)
|
|
{
|
|
int ret;
|
|
int pc;
|
|
|
|
for (pc = 0; pc < item->count; pc++) {
|
|
if (page_count(item->pages[pc]) > 1) {
|
|
unsigned long delay = GNTTAB_UNMAP_REFS_DELAY * (item->age + 1);
|
|
schedule_delayed_work(&item->gnttab_work,
|
|
msecs_to_jiffies(delay));
|
|
return;
|
|
}
|
|
}
|
|
|
|
ret = gnttab_unmap_refs(item->unmap_ops, item->kunmap_ops,
|
|
item->pages, item->count);
|
|
item->done(ret, item);
|
|
}
|
|
|
|
void gnttab_unmap_refs_async(struct gntab_unmap_queue_data* item)
|
|
{
|
|
INIT_DELAYED_WORK(&item->gnttab_work, gnttab_unmap_work);
|
|
item->age = 0;
|
|
|
|
__gnttab_unmap_refs_async(item);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_unmap_refs_async);
|
|
|
|
static void unmap_refs_callback(int result,
|
|
struct gntab_unmap_queue_data *data)
|
|
{
|
|
struct unmap_refs_callback_data *d = data->data;
|
|
|
|
d->result = result;
|
|
complete(&d->completion);
|
|
}
|
|
|
|
int gnttab_unmap_refs_sync(struct gntab_unmap_queue_data *item)
|
|
{
|
|
struct unmap_refs_callback_data data;
|
|
|
|
init_completion(&data.completion);
|
|
item->data = &data;
|
|
item->done = &unmap_refs_callback;
|
|
gnttab_unmap_refs_async(item);
|
|
wait_for_completion(&data.completion);
|
|
|
|
return data.result;
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_unmap_refs_sync);
|
|
|
|
static unsigned int nr_status_frames(unsigned int nr_grant_frames)
|
|
{
|
|
BUG_ON(gnttab_interface == NULL);
|
|
return gnttab_frames(nr_grant_frames, SPP);
|
|
}
|
|
|
|
static int gnttab_map_frames_v1(xen_pfn_t *frames, unsigned int nr_gframes)
|
|
{
|
|
int rc;
|
|
|
|
rc = arch_gnttab_map_shared(frames, nr_gframes,
|
|
gnttab_max_grant_frames(),
|
|
&gnttab_shared.addr);
|
|
BUG_ON(rc);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void gnttab_unmap_frames_v1(void)
|
|
{
|
|
arch_gnttab_unmap(gnttab_shared.addr, nr_grant_frames);
|
|
}
|
|
|
|
static int gnttab_map_frames_v2(xen_pfn_t *frames, unsigned int nr_gframes)
|
|
{
|
|
uint64_t *sframes;
|
|
unsigned int nr_sframes;
|
|
struct gnttab_get_status_frames getframes;
|
|
int rc;
|
|
|
|
nr_sframes = nr_status_frames(nr_gframes);
|
|
|
|
/* No need for kzalloc as it is initialized in following hypercall
|
|
* GNTTABOP_get_status_frames.
|
|
*/
|
|
sframes = kmalloc_array(nr_sframes, sizeof(uint64_t), GFP_ATOMIC);
|
|
if (!sframes)
|
|
return -ENOMEM;
|
|
|
|
getframes.dom = DOMID_SELF;
|
|
getframes.nr_frames = nr_sframes;
|
|
set_xen_guest_handle(getframes.frame_list, sframes);
|
|
|
|
rc = HYPERVISOR_grant_table_op(GNTTABOP_get_status_frames,
|
|
&getframes, 1);
|
|
if (rc == -ENOSYS) {
|
|
kfree(sframes);
|
|
return -ENOSYS;
|
|
}
|
|
|
|
BUG_ON(rc || getframes.status);
|
|
|
|
rc = arch_gnttab_map_status(sframes, nr_sframes,
|
|
nr_status_frames(gnttab_max_grant_frames()),
|
|
&grstatus);
|
|
BUG_ON(rc);
|
|
kfree(sframes);
|
|
|
|
rc = arch_gnttab_map_shared(frames, nr_gframes,
|
|
gnttab_max_grant_frames(),
|
|
&gnttab_shared.addr);
|
|
BUG_ON(rc);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void gnttab_unmap_frames_v2(void)
|
|
{
|
|
arch_gnttab_unmap(gnttab_shared.addr, nr_grant_frames);
|
|
arch_gnttab_unmap(grstatus, nr_status_frames(nr_grant_frames));
|
|
}
|
|
|
|
static int gnttab_map(unsigned int start_idx, unsigned int end_idx)
|
|
{
|
|
struct gnttab_setup_table setup;
|
|
xen_pfn_t *frames;
|
|
unsigned int nr_gframes = end_idx + 1;
|
|
int rc;
|
|
|
|
if (xen_feature(XENFEAT_auto_translated_physmap)) {
|
|
struct xen_add_to_physmap xatp;
|
|
unsigned int i = end_idx;
|
|
rc = 0;
|
|
BUG_ON(xen_auto_xlat_grant_frames.count < nr_gframes);
|
|
/*
|
|
* Loop backwards, so that the first hypercall has the largest
|
|
* index, ensuring that the table will grow only once.
|
|
*/
|
|
do {
|
|
xatp.domid = DOMID_SELF;
|
|
xatp.idx = i;
|
|
xatp.space = XENMAPSPACE_grant_table;
|
|
xatp.gpfn = xen_auto_xlat_grant_frames.pfn[i];
|
|
rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp);
|
|
if (rc != 0) {
|
|
pr_warn("grant table add_to_physmap failed, err=%d\n",
|
|
rc);
|
|
break;
|
|
}
|
|
} while (i-- > start_idx);
|
|
|
|
return rc;
|
|
}
|
|
|
|
/* No need for kzalloc as it is initialized in following hypercall
|
|
* GNTTABOP_setup_table.
|
|
*/
|
|
frames = kmalloc_array(nr_gframes, sizeof(unsigned long), GFP_ATOMIC);
|
|
if (!frames)
|
|
return -ENOMEM;
|
|
|
|
setup.dom = DOMID_SELF;
|
|
setup.nr_frames = nr_gframes;
|
|
set_xen_guest_handle(setup.frame_list, frames);
|
|
|
|
rc = HYPERVISOR_grant_table_op(GNTTABOP_setup_table, &setup, 1);
|
|
if (rc == -ENOSYS) {
|
|
kfree(frames);
|
|
return -ENOSYS;
|
|
}
|
|
|
|
BUG_ON(rc || setup.status);
|
|
|
|
rc = gnttab_interface->map_frames(frames, nr_gframes);
|
|
|
|
kfree(frames);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static const struct gnttab_ops gnttab_v1_ops = {
|
|
.version = 1,
|
|
.grefs_per_grant_frame = XEN_PAGE_SIZE /
|
|
sizeof(struct grant_entry_v1),
|
|
.map_frames = gnttab_map_frames_v1,
|
|
.unmap_frames = gnttab_unmap_frames_v1,
|
|
.update_entry = gnttab_update_entry_v1,
|
|
.end_foreign_access_ref = gnttab_end_foreign_access_ref_v1,
|
|
.end_foreign_transfer_ref = gnttab_end_foreign_transfer_ref_v1,
|
|
.query_foreign_access = gnttab_query_foreign_access_v1,
|
|
};
|
|
|
|
static const struct gnttab_ops gnttab_v2_ops = {
|
|
.version = 2,
|
|
.grefs_per_grant_frame = XEN_PAGE_SIZE /
|
|
sizeof(union grant_entry_v2),
|
|
.map_frames = gnttab_map_frames_v2,
|
|
.unmap_frames = gnttab_unmap_frames_v2,
|
|
.update_entry = gnttab_update_entry_v2,
|
|
.end_foreign_access_ref = gnttab_end_foreign_access_ref_v2,
|
|
.end_foreign_transfer_ref = gnttab_end_foreign_transfer_ref_v2,
|
|
.query_foreign_access = gnttab_query_foreign_access_v2,
|
|
};
|
|
|
|
static bool gnttab_need_v2(void)
|
|
{
|
|
#ifdef CONFIG_X86
|
|
uint32_t base, width;
|
|
|
|
if (xen_pv_domain()) {
|
|
base = xen_cpuid_base();
|
|
if (cpuid_eax(base) < 5)
|
|
return false; /* Information not available, use V1. */
|
|
width = cpuid_ebx(base + 5) &
|
|
XEN_CPUID_MACHINE_ADDRESS_WIDTH_MASK;
|
|
return width > 32 + PAGE_SHIFT;
|
|
}
|
|
#endif
|
|
return !!(max_possible_pfn >> 32);
|
|
}
|
|
|
|
static void gnttab_request_version(void)
|
|
{
|
|
long rc;
|
|
struct gnttab_set_version gsv;
|
|
|
|
if (gnttab_need_v2())
|
|
gsv.version = 2;
|
|
else
|
|
gsv.version = 1;
|
|
|
|
/* Boot parameter overrides automatic selection. */
|
|
if (xen_gnttab_version >= 1 && xen_gnttab_version <= 2)
|
|
gsv.version = xen_gnttab_version;
|
|
|
|
rc = HYPERVISOR_grant_table_op(GNTTABOP_set_version, &gsv, 1);
|
|
if (rc == 0 && gsv.version == 2)
|
|
gnttab_interface = &gnttab_v2_ops;
|
|
else
|
|
gnttab_interface = &gnttab_v1_ops;
|
|
pr_info("Grant tables using version %d layout\n",
|
|
gnttab_interface->version);
|
|
}
|
|
|
|
static int gnttab_setup(void)
|
|
{
|
|
unsigned int max_nr_gframes;
|
|
|
|
max_nr_gframes = gnttab_max_grant_frames();
|
|
if (max_nr_gframes < nr_grant_frames)
|
|
return -ENOSYS;
|
|
|
|
if (xen_feature(XENFEAT_auto_translated_physmap) && gnttab_shared.addr == NULL) {
|
|
gnttab_shared.addr = xen_auto_xlat_grant_frames.vaddr;
|
|
if (gnttab_shared.addr == NULL) {
|
|
pr_warn("gnttab share frames is not mapped!\n");
|
|
return -ENOMEM;
|
|
}
|
|
}
|
|
return gnttab_map(0, nr_grant_frames - 1);
|
|
}
|
|
|
|
int gnttab_resume(void)
|
|
{
|
|
gnttab_request_version();
|
|
return gnttab_setup();
|
|
}
|
|
|
|
int gnttab_suspend(void)
|
|
{
|
|
if (!xen_feature(XENFEAT_auto_translated_physmap))
|
|
gnttab_interface->unmap_frames();
|
|
return 0;
|
|
}
|
|
|
|
static int gnttab_expand(unsigned int req_entries)
|
|
{
|
|
int rc;
|
|
unsigned int cur, extra;
|
|
|
|
BUG_ON(gnttab_interface == NULL);
|
|
cur = nr_grant_frames;
|
|
extra = ((req_entries + gnttab_interface->grefs_per_grant_frame - 1) /
|
|
gnttab_interface->grefs_per_grant_frame);
|
|
if (cur + extra > gnttab_max_grant_frames()) {
|
|
pr_warn_ratelimited("xen/grant-table: max_grant_frames reached"
|
|
" cur=%u extra=%u limit=%u"
|
|
" gnttab_free_count=%u req_entries=%u\n",
|
|
cur, extra, gnttab_max_grant_frames(),
|
|
gnttab_free_count, req_entries);
|
|
return -ENOSPC;
|
|
}
|
|
|
|
rc = gnttab_map(cur, cur + extra - 1);
|
|
if (rc == 0)
|
|
rc = grow_gnttab_list(extra);
|
|
|
|
return rc;
|
|
}
|
|
|
|
int gnttab_init(void)
|
|
{
|
|
int i;
|
|
unsigned long max_nr_grant_frames;
|
|
unsigned int max_nr_glist_frames, nr_glist_frames;
|
|
unsigned int nr_init_grefs;
|
|
int ret;
|
|
|
|
gnttab_request_version();
|
|
max_nr_grant_frames = gnttab_max_grant_frames();
|
|
nr_grant_frames = 1;
|
|
|
|
/* Determine the maximum number of frames required for the
|
|
* grant reference free list on the current hypervisor.
|
|
*/
|
|
BUG_ON(gnttab_interface == NULL);
|
|
max_nr_glist_frames = (max_nr_grant_frames *
|
|
gnttab_interface->grefs_per_grant_frame / RPP);
|
|
|
|
gnttab_list = kmalloc_array(max_nr_glist_frames,
|
|
sizeof(grant_ref_t *),
|
|
GFP_KERNEL);
|
|
if (gnttab_list == NULL)
|
|
return -ENOMEM;
|
|
|
|
nr_glist_frames = gnttab_frames(nr_grant_frames, RPP);
|
|
for (i = 0; i < nr_glist_frames; i++) {
|
|
gnttab_list[i] = (grant_ref_t *)__get_free_page(GFP_KERNEL);
|
|
if (gnttab_list[i] == NULL) {
|
|
ret = -ENOMEM;
|
|
goto ini_nomem;
|
|
}
|
|
}
|
|
|
|
ret = arch_gnttab_init(max_nr_grant_frames,
|
|
nr_status_frames(max_nr_grant_frames));
|
|
if (ret < 0)
|
|
goto ini_nomem;
|
|
|
|
if (gnttab_setup() < 0) {
|
|
ret = -ENODEV;
|
|
goto ini_nomem;
|
|
}
|
|
|
|
nr_init_grefs = nr_grant_frames *
|
|
gnttab_interface->grefs_per_grant_frame;
|
|
|
|
for (i = NR_RESERVED_ENTRIES; i < nr_init_grefs - 1; i++)
|
|
gnttab_entry(i) = i + 1;
|
|
|
|
gnttab_entry(nr_init_grefs - 1) = GNTTAB_LIST_END;
|
|
gnttab_free_count = nr_init_grefs - NR_RESERVED_ENTRIES;
|
|
gnttab_free_head = NR_RESERVED_ENTRIES;
|
|
|
|
printk("Grant table initialized\n");
|
|
return 0;
|
|
|
|
ini_nomem:
|
|
for (i--; i >= 0; i--)
|
|
free_page((unsigned long)gnttab_list[i]);
|
|
kfree(gnttab_list);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(gnttab_init);
|
|
|
|
static int __gnttab_init(void)
|
|
{
|
|
if (!xen_domain())
|
|
return -ENODEV;
|
|
|
|
/* Delay grant-table initialization in the PV on HVM case */
|
|
if (xen_hvm_domain() && !xen_pvh_domain())
|
|
return 0;
|
|
|
|
return gnttab_init();
|
|
}
|
|
/* Starts after core_initcall so that xen_pvh_gnttab_setup can be called
|
|
* beforehand to initialize xen_auto_xlat_grant_frames. */
|
|
core_initcall_sync(__gnttab_init);
|