When an ioreq server is created the code currently stores the id of the emulating domain, but does not take a reference on that domain.
This patch modifies the code to hold a reference for the lifetime of the ioreq server. Signed-off-by: Paul Durrant <paul.durr...@citrix.com> --- Cc: Jan Beulich <jbeul...@suse.com> Cc: Andrew Cooper <andrew.coop...@citrix.com> --- xen/arch/x86/hvm/ioreq.c | 33 ++++++++++++++++++++++----------- xen/include/asm-x86/hvm/domain.h | 4 +--- 2 files changed, 23 insertions(+), 14 deletions(-) diff --git a/xen/arch/x86/hvm/ioreq.c b/xen/arch/x86/hvm/ioreq.c index 2b9e5562dd..066c997c93 100644 --- a/xen/arch/x86/hvm/ioreq.c +++ b/xen/arch/x86/hvm/ioreq.c @@ -218,7 +218,7 @@ static void hvm_unmap_ioreq_page(struct hvm_ioreq_server *s, bool buf) static int hvm_map_ioreq_page( struct hvm_ioreq_server *s, bool buf, unsigned long gfn) { - struct domain *d = s->domain; + struct domain *d = s->target; struct hvm_ioreq_page *iorp = buf ? &s->bufioreq : &s->ioreq; struct page_info *page; void *va; @@ -305,6 +305,7 @@ static int hvm_ioreq_server_add_vcpu(struct hvm_ioreq_server *s, bool is_default, struct vcpu *v) { struct hvm_ioreq_vcpu *sv; + domid_t domid; int rc; sv = xzalloc(struct hvm_ioreq_vcpu); @@ -315,7 +316,9 @@ static int hvm_ioreq_server_add_vcpu(struct hvm_ioreq_server *s, spin_lock(&s->lock); - rc = alloc_unbound_xen_event_channel(v->domain, v->vcpu_id, s->domid, + domid = s->emulator->domain_id; + + rc = alloc_unbound_xen_event_channel(v->domain, v->vcpu_id, domid, NULL); if ( rc < 0 ) goto fail2; @@ -324,9 +327,9 @@ static int hvm_ioreq_server_add_vcpu(struct hvm_ioreq_server *s, if ( v->vcpu_id == 0 && s->bufioreq.va != NULL ) { - struct domain *d = s->domain; + struct domain *d = s->target; - rc = alloc_unbound_xen_event_channel(v->domain, 0, s->domid, NULL); + rc = alloc_unbound_xen_event_channel(v->domain, 0, domid, NULL); if ( rc < 0 ) goto fail3; @@ -434,7 +437,7 @@ static int hvm_ioreq_server_setup_pages(struct hvm_ioreq_server *s, bool is_default, bool handle_bufioreq) { - struct domain *d = s->domain; + struct domain *d = s->target; unsigned long ioreq_gfn = gfn_x(INVALID_GFN); unsigned long bufioreq_gfn = gfn_x(INVALID_GFN); int rc; @@ -471,7 +474,7 @@ static int hvm_ioreq_server_setup_pages(struct hvm_ioreq_server *s, static void hvm_ioreq_server_unmap_pages(struct hvm_ioreq_server *s, bool is_default) { - struct domain *d = s->domain; + struct domain *d = s->target; bool handle_bufioreq = !!s->bufioreq.va; if ( handle_bufioreq ) @@ -521,7 +524,7 @@ static int hvm_ioreq_server_alloc_rangesets(struct hvm_ioreq_server *s, if ( rc ) goto fail; - s->range[i] = rangeset_new(s->domain, name, + s->range[i] = rangeset_new(s->target, name, RANGESETF_prettyprint_hex); xfree(name); @@ -545,7 +548,7 @@ static int hvm_ioreq_server_alloc_rangesets(struct hvm_ioreq_server *s, static void hvm_ioreq_server_enable(struct hvm_ioreq_server *s, bool is_default) { - struct domain *d = s->domain; + struct domain *d = s->target; struct hvm_ioreq_vcpu *sv; bool handle_bufioreq = !!s->bufioreq.va; @@ -576,7 +579,7 @@ static void hvm_ioreq_server_enable(struct hvm_ioreq_server *s, static void hvm_ioreq_server_disable(struct hvm_ioreq_server *s, bool is_default) { - struct domain *d = s->domain; + struct domain *d = s->target; bool handle_bufioreq = !!s->bufioreq.va; spin_lock(&s->lock); @@ -602,12 +605,17 @@ static int hvm_ioreq_server_init(struct hvm_ioreq_server *s, struct domain *d, bool is_default, int bufioreq_handling, ioservid_t id) { + struct domain *currd = current->domain; struct vcpu *v; int rc; s->id = id; - s->domain = d; - s->domid = current->domain->domain_id; + s->target = d; + + if ( !get_domain(currd) ) + return -EACCES; + + s->emulator = currd; spin_lock_init(&s->lock); INIT_LIST_HEAD(&s->ioreq_vcpu_list); @@ -641,6 +649,7 @@ static int hvm_ioreq_server_init(struct hvm_ioreq_server *s, fail_map: hvm_ioreq_server_free_rangesets(s, is_default); + put_domain(s->emulator); return rc; } @@ -651,6 +660,8 @@ static void hvm_ioreq_server_deinit(struct hvm_ioreq_server *s, hvm_ioreq_server_remove_all_vcpus(s); hvm_ioreq_server_unmap_pages(s, is_default); hvm_ioreq_server_free_rangesets(s, is_default); + + put_domain(s->emulator); } static ioservid_t next_ioservid(struct domain *d) diff --git a/xen/include/asm-x86/hvm/domain.h b/xen/include/asm-x86/hvm/domain.h index 7f128c05ff..6e03d024c8 100644 --- a/xen/include/asm-x86/hvm/domain.h +++ b/xen/include/asm-x86/hvm/domain.h @@ -53,13 +53,11 @@ struct hvm_ioreq_vcpu { struct hvm_ioreq_server { struct list_head list_entry; - struct domain *domain; + struct domain *target, *emulator; /* Lock to serialize toolstack modifications */ spinlock_t lock; - /* Domain id of emulating domain */ - domid_t domid; ioservid_t id; struct hvm_ioreq_page ioreq; struct list_head ioreq_vcpu_list; -- 2.11.0 _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel