/**
* 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)
{
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]);
}
}
free_xenballooned_pages(nr_pages, pages);
}
static int __init xlated_setup_gnttab_pages(void)
{
struct page **pages;
xen_pfn_t *pfns;
int rc;
unsigned int i;
unsigned long nr_grant_frames = gnttab_max_grant_frames();
BUG_ON(nr_grant_frames == 0);
pages = kcalloc(nr_grant_frames, sizeof(pages[0]), GFP_KERNEL);
if (!pages)
return -ENOMEM;
pfns = kcalloc(nr_grant_frames, sizeof(pfns[0]), GFP_KERNEL);
if (!pfns) {
kfree(pages);
return -ENOMEM;
}
rc = alloc_xenballooned_pages(nr_grant_frames, pages, 0 /* lowmem */);
if (rc) {
pr_warn("%s Couldn't balloon alloc %ld pfns rc:%d\n", __func__,
nr_grant_frames, rc);
kfree(pages);
kfree(pfns);
return rc;
}
for (i = 0; i < nr_grant_frames; i++)
pfns[i] = page_to_pfn(pages[i]);
rc = arch_gnttab_map_shared(pfns, nr_grant_frames, nr_grant_frames,
&xen_auto_xlat_grant_frames.vaddr);
if (rc) {
pr_warn("%s Couldn't map %ld pfns rc:%d\n", __func__,
nr_grant_frames, rc);
free_xenballooned_pages(nr_grant_frames, pages);
kfree(pages);
kfree(pfns);
return rc;
}
kfree(pages);
xen_auto_xlat_grant_frames.pfn = pfns;
xen_auto_xlat_grant_frames.count = nr_grant_frames;
return 0;
}
/*
* PVH: we need three things: virtual address, pfns, and mfns. The pfns
* are allocated via ballooning, then we call arch_gnttab_map_shared to
* allocate the VA and put pfn's in the pte's for the VA. The mfn's are
* finally allocated in gnttab_map() by xen which also populates the P2M.
*/
static int xlated_setup_gnttab_pages(unsigned long numpages, void **addr)
{
int i, rc;
unsigned long pfns[numpages];
struct page *pages[numpages];
rc = alloc_xenballooned_pages(numpages, pages, 0);
if (rc != 0) {
pr_warn("%s Couldn't balloon alloc %ld pfns rc:%d\n", __func__,
numpages, rc);
return rc;
}
for (i = 0; i < numpages; i++)
pfns[i] = page_to_pfn(pages[i]);
rc = arch_gnttab_map_shared(pfns, numpages, numpages, addr);
if (rc != 0)
free_xenballooned_pages(numpages, pages);
return rc;
}
int omx_xen_deregister_user_segment(omx_xenif_t * omx_xenif, uint32_t id,
uint32_t sid, uint8_t eid)
{
struct gnttab_unmap_grant_ref ops;
struct backend_info *be = omx_xenif->be;
struct omxback_dev *dev = be->omxdev;
struct omx_endpoint *endpoint = dev->endpoints[eid];
struct omx_xen_user_region *region;
struct omx_xen_user_region_segment *seg;
int i, k, ret = 0;
unsigned int level;
dprintk_in();
TIMER_START(&t_dereg_seg);
if (eid < 0 && eid >= 255) {
printk_err
("Wrong endpoint number (%u) check your frontend/backend communication!\n",
eid);
ret = -EINVAL;
goto out;
}
region = rcu_dereference_protected(endpoint->xen_regions[id], 1);
if (unlikely(!region)) {
printk_err(
"%s: Cannot access non-existing region %d\n", __func__, id);
//ret = -EINVAL;
goto out;
}
seg = ®ion->segments[sid];
TIMER_START(&t_release_grants);
if (!seg->unmap) {
printk_err("seg->unmap is NULL\n");
ret = -EINVAL;
goto out;
}
gnttab_unmap_refs(seg->unmap, NULL, seg->pages, seg->nr_pages);
TIMER_STOP(&t_release_grants);
TIMER_START(&t_release_gref_list);
for (k = 0; k < seg->nr_parts; k++) {
#ifdef EXTRA_DEBUG_OMX
if (!seg->vm_gref) {
printk(KERN_ERR "vm_gref is NULL\n");
ret = -EFAULT;
goto out;
}
if (!seg->vm_gref[k]) {
printk(KERN_ERR "vm_gref[%d] is NULL\n", k);
ret = -EFAULT;
goto out;
}
if (!seg->vm_gref[k]->addr) {
printk(KERN_ERR "vm_gref[%d]->addr is NULL\n", k);
ret = -EFAULT;
goto out;
}
if (!seg->all_handle[k]) {
printk(KERN_ERR "all_handle[%d] is NULL\n", k);
ret = -EINVAL;
goto out;
}
#endif
gnttab_set_unmap_op(&ops, (unsigned long)seg->vm_gref[k]->addr,
GNTMAP_host_map | GNTMAP_contains_pte,
seg->all_handle[k]);
ops.host_addr =
arbitrary_virt_to_machine(lookup_address
((unsigned long)(seg->vm_gref[k]->
addr),
&level)).maddr;
dprintk_deb("putting vm_area[%d] %#lx, handle = %#x \n", k,
(unsigned long)seg->vm_gref[k], seg->all_handle[k]);
if (HYPERVISOR_grant_table_op
(GNTTABOP_unmap_grant_ref, &ops, 1)){
printk_err
("HYPERVISOR operation failed\n");
//BUG();
}
if (ops.status) {
printk_err
("HYPERVISOR unmap grant ref[%d]=%#lx failed status = %d",
k, seg->all_handle[k], ops.status);
ret = ops.status;
goto out;
}
}
TIMER_STOP(&t_release_gref_list);
TIMER_START(&t_free_pages);
for (k=0;k<seg->nr_parts;k++)
if (ops.status == GNTST_okay)
free_vm_area(seg->vm_gref[k]);
kfree(seg->map);
kfree(seg->unmap);
kfree(seg->gref_list);
#ifdef OMX_XEN_COOKIES
omx_xen_page_put_cookie(omx_xenif, seg->cookie);
#else
free_xenballooned_pages(seg->nr_pages, seg->pages);
kfree(seg->pages);
#endif
TIMER_STOP(&t_free_pages);
out:
TIMER_STOP(&t_dereg_seg);
dprintk_out();
return ret;
}