int guest_remove_page(struct domain *d, unsigned long gmfn) { struct page_info *page; #ifdef CONFIG_X86 p2m_type_t p2mt; #endif unsigned long mfn; #ifdef CONFIG_X86 mfn = mfn_x(gfn_to_mfn(p2m_get_hostp2m(d), gmfn, &p2mt)); if ( unlikely(p2m_is_paging(p2mt)) ) { guest_physmap_remove_page(d, gmfn, mfn, 0); p2m_mem_paging_drop_page(p2m_get_hostp2m(d), gmfn); return 1; } #else mfn = gmfn_to_mfn(d, gmfn); #endif if ( unlikely(!mfn_valid(mfn)) ) { gdprintk(XENLOG_INFO, "Domain %u page number %lx invalid\n", d->domain_id, gmfn); return 0; } page = mfn_to_page(mfn); #ifdef CONFIG_X86 /* If gmfn is shared, just drop the guest reference (which may or may not * free the page) */ if(p2m_is_shared(p2mt)) { put_page_and_type(page); guest_physmap_remove_page(d, gmfn, mfn, 0); return 1; } #endif /* CONFIG_X86 */ if ( unlikely(!get_page(page, d)) ) { gdprintk(XENLOG_INFO, "Bad page free for domain %u\n", d->domain_id); return 0; } if ( test_and_clear_bit(_PGT_pinned, &page->u.inuse.type_info) ) put_page_and_type(page); if ( test_and_clear_bit(_PGC_allocated, &page->count_info) ) put_page(page); guest_physmap_remove_page(d, gmfn, mfn, 0); put_page(page); return 1; }
int guest_remove_page(struct domain *d, unsigned long gmfn) { struct page_info *page; #ifdef CONFIG_X86 p2m_type_t p2mt; #endif unsigned long mfn; #ifdef CONFIG_X86 mfn = mfn_x(get_gfn_query(d, gmfn, &p2mt)); if ( unlikely(p2m_is_paging(p2mt)) ) { guest_physmap_remove_page(d, gmfn, mfn, 0); put_gfn(d, gmfn); /* If the page hasn't yet been paged out, there is an * actual page that needs to be released. */ if ( p2mt == p2m_ram_paging_out ) { ASSERT(mfn_valid(mfn)); page = mfn_to_page(mfn); if ( test_and_clear_bit(_PGC_allocated, &page->count_info) ) put_page(page); } p2m_mem_paging_drop_page(d, gmfn, p2mt); return 1; } if ( p2mt == p2m_mmio_direct ) { clear_mmio_p2m_entry(d, gmfn, _mfn(mfn)); put_gfn(d, gmfn); return 1; } #else mfn = gmfn_to_mfn(d, gmfn); #endif if ( unlikely(!mfn_valid(mfn)) ) { put_gfn(d, gmfn); gdprintk(XENLOG_INFO, "Domain %u page number %lx invalid\n", d->domain_id, gmfn); return 0; } #ifdef CONFIG_X86 if ( p2m_is_shared(p2mt) ) { /* Unshare the page, bail out on error. We unshare because * we might be the only one using this shared page, and we * need to trigger proper cleanup. Once done, this is * like any other page. */ if ( mem_sharing_unshare_page(d, gmfn, 0) ) { put_gfn(d, gmfn); (void)mem_sharing_notify_enomem(d, gmfn, 0); return 0; } /* Maybe the mfn changed */ mfn = mfn_x(get_gfn_query_unlocked(d, gmfn, &p2mt)); ASSERT(!p2m_is_shared(p2mt)); } #endif /* CONFIG_X86 */ page = mfn_to_page(mfn); if ( unlikely(!get_page(page, d)) ) { put_gfn(d, gmfn); gdprintk(XENLOG_INFO, "Bad page free for domain %u\n", d->domain_id); return 0; } if ( test_and_clear_bit(_PGT_pinned, &page->u.inuse.type_info) ) put_page_and_type(page); /* * With the lack of an IOMMU on some platforms, domains with DMA-capable * device must retrieve the same pfn when the hypercall populate_physmap * is called. * * For this purpose (and to match populate_physmap() behavior), the page * is kept allocated. */ if ( !is_domain_direct_mapped(d) && test_and_clear_bit(_PGC_allocated, &page->count_info) ) put_page(page); guest_physmap_remove_page(d, gmfn, mfn, 0); put_page(page); put_gfn(d, gmfn); return 1; }
int guest_remove_page(struct domain *d, unsigned long gmfn) { struct page_info *page; #ifdef CONFIG_X86 p2m_type_t p2mt; #endif unsigned long mfn; #ifdef CONFIG_X86 mfn = mfn_x(get_gfn_query(d, gmfn, &p2mt)); if ( unlikely(p2m_is_paging(p2mt)) ) { guest_physmap_remove_page(d, gmfn, mfn, 0); put_gfn(d, gmfn); /* If the page hasn't yet been paged out, there is an * actual page that needs to be released. */ if ( p2mt == p2m_ram_paging_out ) { ASSERT(mfn_valid(mfn)); page = mfn_to_page(mfn); if ( test_and_clear_bit(_PGC_allocated, &page->count_info) ) put_page(page); } p2m_mem_paging_drop_page(d, gmfn, p2mt); return 1; } #else mfn = gmfn_to_mfn(d, gmfn); #endif if ( unlikely(!mfn_valid(mfn)) ) { put_gfn(d, gmfn); gdprintk(XENLOG_INFO, "Domain %u page number %lx invalid\n", d->domain_id, gmfn); return 0; } #ifdef CONFIG_X86_64 if ( p2m_is_shared(p2mt) ) { /* Unshare the page, bail out on error. We unshare because * we might be the only one using this shared page, and we * need to trigger proper cleanup. Once done, this is * like any other page. */ if ( mem_sharing_unshare_page(d, gmfn, 0) ) { put_gfn(d, gmfn); (void)mem_sharing_notify_enomem(d, gmfn, 0); return 0; } /* Maybe the mfn changed */ mfn = mfn_x(get_gfn_query_unlocked(d, gmfn, &p2mt)); ASSERT(!p2m_is_shared(p2mt)); } #endif /* CONFIG_X86_64 */ page = mfn_to_page(mfn); if ( unlikely(!get_page(page, d)) ) { put_gfn(d, gmfn); gdprintk(XENLOG_INFO, "Bad page free for domain %u\n", d->domain_id); return 0; } if ( test_and_clear_bit(_PGT_pinned, &page->u.inuse.type_info) ) put_page_and_type(page); if ( test_and_clear_bit(_PGC_allocated, &page->count_info) ) put_page(page); guest_physmap_remove_page(d, gmfn, mfn, 0); put_page(page); put_gfn(d, gmfn); return 1; }