Support for VM generation ID save/restore and migrate

diff -r 03138a08366b -r a8c26cdf079c tools/libxl/libxl_create.c
@@ -320,11 +320,8 @@ int libxl__domain_make(libxl__gc *gc, li
   * on exit (even error exit), domid may be valid and refer to a domain */
 {
     libxl_ctx *ctx = libxl__gc_owner(gc);
-    int flags, ret, i, rc;
+    int flags, ret, rc;
     char *uuid_string;
-    char *rw_paths[] = { "control/shutdown", "device", "device/suspend/event-channel" , "data"};
-    char *ro_paths[] = { "cpu", "memory", "device", "error", "drivers",
-                         "control", "attr", "messages" };
     char *dom_path, *vm_path, *libxl_path;
     struct xs_permissions roperm[2];
     struct xs_permissions rwperm[1];

@@ -384,6 +381,7 @@ int libxl__domain_make(libxl__gc *gc, li
         rc = ERROR_FAIL;
         goto out;
     }
+
     noperm[0].id = 0;
     noperm[0].perms = XS_PERM_NONE;
 

@@ -391,6 +389,7 @@ int libxl__domain_make(libxl__gc *gc, li
     roperm[0].perms = XS_PERM_NONE;
     roperm[1].id = *domid;
     roperm[1].perms = XS_PERM_READ;
+
     rwperm[0].id = *domid;
     rwperm[0].perms = XS_PERM_NONE;
 

@@ -398,32 +397,42 @@ retry_transaction:
     t = xs_transaction_start(ctx->xsh);
 
     xs_rm(ctx->xsh, t, dom_path);
-    xs_mkdir(ctx->xsh, t, dom_path);
-    xs_set_permissions(ctx->xsh, t, dom_path, roperm, ARRAY_SIZE(roperm));
+    libxl__xs_mkdir(gc, t, dom_path, roperm, ARRAY_SIZE(roperm));
+
 
     xs_rm(ctx->xsh, t, vm_path);
-    xs_mkdir(ctx->xsh, t, vm_path);
-    xs_set_permissions(ctx->xsh, t, vm_path, roperm, ARRAY_SIZE(roperm));
+    libxl__xs_mkdir(gc, t, vm_path, roperm, ARRAY_SIZE(roperm));
 
     xs_rm(ctx->xsh, t, libxl_path);
-    xs_mkdir(ctx->xsh, t, libxl_path);
-    xs_set_permissions(ctx->xsh, t, libxl_path, noperm, ARRAY_SIZE(noperm));
+    libxl__xs_mkdir(gc, t, libxl_path, noperm, ARRAY_SIZE(noperm));
 
     xs_write(ctx->xsh, t, libxl__sprintf(gc, "%s/vm", dom_path), vm_path, strlen(vm_path));
     rc = libxl__domain_rename(gc, *domid, 0, info->name, t);
     if (rc)
         goto out;
 
-    for (i = 0; i < ARRAY_SIZE(rw_paths); i++) {
-        char *path = libxl__sprintf(gc, "%s/%s", dom_path, rw_paths[i]);
-        xs_mkdir(ctx->xsh, t, path);
-        xs_set_permissions(ctx->xsh, t, path, rwperm, ARRAY_SIZE(rwperm));
-    }
-    for (i = 0; i < ARRAY_SIZE(ro_paths); i++) {
-        char *path = libxl__sprintf(gc, "%s/%s", dom_path, ro_paths[i]);
-        xs_mkdir(ctx->xsh, t, path);
-        xs_set_permissions(ctx->xsh, t, path, roperm, ARRAY_SIZE(roperm));
-    }
+    libxl__xs_mkdir(gc, t,
+                    libxl__sprintf(gc, "%s/cpu", dom_path),
+                    roperm, ARRAY_SIZE(roperm));
+    libxl__xs_mkdir(gc, t,
+                    libxl__sprintf(gc, "%s/memory", dom_path),
+                    roperm, ARRAY_SIZE(roperm));
+    libxl__xs_mkdir(gc, t,
+                    libxl__sprintf(gc, "%s/device", dom_path),
+                    roperm, ARRAY_SIZE(roperm));
+    libxl__xs_mkdir(gc, t,
+                    libxl__sprintf(gc, "%s/control", dom_path),
+                    roperm, ARRAY_SIZE(roperm));
+
+    libxl__xs_mkdir(gc, t,
+                    libxl__sprintf(gc, "%s/control/shutdown", dom_path),
+                    rwperm, ARRAY_SIZE(rwperm));
+    libxl__xs_mkdir(gc, t,
+                    libxl__sprintf(gc, "%s/device/suspend/event-channel", dom_path),
+                    rwperm, ARRAY_SIZE(rwperm));
+    libxl__xs_mkdir(gc, t,
+                    libxl__sprintf(gc, "%s/data", dom_path),
+                    rwperm, ARRAY_SIZE(rwperm));
 
     xs_write(ctx->xsh, t, libxl__sprintf(gc, "%s/uuid", vm_path), uuid_string, strlen(uuid_string));
     xs_write(ctx->xsh, t, libxl__sprintf(gc, "%s/name", vm_path), info->name, strlen(info->name));

diff -r 03138a08366b -r a8c26cdf079c tools/libxl/libxl_internal.h
@@ -204,6 +204,9 @@ _hidden char *libxl__xs_read(libxl__gc *
 _hidden char **libxl__xs_directory(libxl__gc *gc, xs_transaction_t t,
                                    const char *path, unsigned int *nb);
    /* On error: returns NULL, sets errno (no logging) */
+_hidden bool libxl__xs_mkdir(libxl__gc *gc, xs_transaction_t t,
+                             const char *path, struct xs_permissions *perms,
+			     unsigned int num_perms);
 
 _hidden char *libxl__xs_libxl_path(libxl__gc *gc, uint32_t domid);
 

diff -r 03138a08366b -r a8c26cdf079c tools/libxl/libxl_xshelp.c
@@ -122,6 +122,16 @@ char **libxl__xs_directory(libxl__gc *gc
     return ret;
 }
 
+bool libxl__xs_mkdir(libxl__gc *gc, xs_transaction_t t,
+                     const char *path, struct xs_permissions *perms,
+			         unsigned int num_perms)
+{
+    libxl_ctx *ctx = libxl__gc_owner(gc);
+    if (!xs_mkdir(ctx->xsh, t, path))
+        return false;
+    return xs_set_permissions(ctx->xsh, t, path, perms, num_perms);
+}
+
 char *libxl__xs_libxl_path(libxl__gc *gc, uint32_t domid)
 {
     libxl_ctx *ctx = libxl__gc_owner(gc);

diff -r a8c26cdf079c -r 83dad81a557e tools/libxl/libxl_create.c
@@ -423,6 +423,10 @@ retry_transaction:
     libxl__xs_mkdir(gc, t,
                     libxl__sprintf(gc, "%s/control", dom_path),
                     roperm, ARRAY_SIZE(roperm));
+    if (info->type == LIBXL_DOMAIN_TYPE_HVM)
+        libxl__xs_mkdir(gc, t,
+                        libxl__sprintf(gc, "%s/hvmloader", dom_path),
+                        roperm, ARRAY_SIZE(roperm));
 
     libxl__xs_mkdir(gc, t,
                     libxl__sprintf(gc, "%s/control/shutdown", dom_path),

@@ -433,6 +437,10 @@ retry_transaction:
     libxl__xs_mkdir(gc, t,
                     libxl__sprintf(gc, "%s/data", dom_path),
                     rwperm, ARRAY_SIZE(rwperm));
+    if (info->type == LIBXL_DOMAIN_TYPE_HVM)
+        libxl__xs_mkdir(gc, t,
+                        libxl__sprintf(gc, "%s/hvmloader/generation-id-address", dom_path),
+                        rwperm, ARRAY_SIZE(rwperm));
 
     xs_write(ctx->xsh, t, libxl__sprintf(gc, "%s/uuid", vm_path), uuid_string, strlen(uuid_string));
     xs_write(ctx->xsh, t, libxl__sprintf(gc, "%s/name", vm_path), info->name, strlen(info->name));

diff -r a8c26cdf079c -r 83dad81a557e tools/libxl/libxl_dm.c
@@ -821,10 +821,10 @@ int libxl__create_device_model(libxl__gc
         goto out;
     }
 
-    path = libxl__sprintf(gc, "/local/domain/%d/hvmloader", info->domid);
-    xs_mkdir(ctx->xsh, XBT_NULL, path);
-    libxl__xs_write(gc, XBT_NULL, libxl__sprintf(gc, "%s/bios", path),
+    path = xs_get_domain_path(ctx->xsh, info->domid);
+    libxl__xs_write(gc, XBT_NULL, libxl__sprintf(gc, "%s/hvmloader/bios", path),
                     "%s", libxl__domain_bios(gc, info));
+    free(path);
 
     path = libxl__sprintf(gc, "/local/domain/0/device-model/%d", info->domid);
     xs_mkdir(ctx->xsh, XBT_NULL, path);

diff -r 83dad81a557e -r bd8e9eb71611 tools/firmware/hvmloader/acpi/build.c
@@ -309,7 +309,7 @@ unsigned long new_vm_gid(void)
     if ( snprintf(addr, sizeof(addr), "0x%lx", virt_to_phys(buf))
          >= sizeof(addr) )
         return 0;
-    xenstore_write("data/generation-id", addr);
+    xenstore_write("hvmloader/generation-id-address", addr);
 
     gid = strtoll(xenstore_read("platform/generation-id", "0"), NULL, 0);
     *(uint64_t *)buf = gid;

diff -r bd8e9eb71611 -r 5df9a24e0078 tools/libxc/ia64/xc_ia64_linux_restore.c
@@ -548,7 +548,9 @@ int
 xc_domain_restore(xc_interface *xch, int io_fd, uint32_t dom,
                   unsigned int store_evtchn, unsigned long *store_mfn,
                   unsigned int console_evtchn, unsigned long *console_mfn,
-                  unsigned int hvm, unsigned int pae, int superpages)
+                  unsigned int hvm, unsigned int pae, int superpages,
+                  int no_incr_generationid,
+                  unsigned long *vm_generationid_addr)
 {
     DECLARE_DOMCTL;
     int rc = 1;

diff -r bd8e9eb71611 -r 5df9a24e0078 tools/libxc/ia64/xc_ia64_linux_save.c
@@ -382,7 +382,8 @@ out:
 int
 xc_domain_save(xc_interface *xch, int io_fd, uint32_t dom, uint32_t max_iters,
                uint32_t max_factor, uint32_t flags,
-               struct save_callbacks* callbacks, int hvm)
+               struct save_callbacks* callbacks, int hvm,
+               unsigned long vm_generationid_addr)
 {
     DECLARE_DOMCTL;
     xc_dominfo_t info;

73 lines not on this page · raw message

diff -r bd8e9eb71611 -r 5df9a24e0078 tools/libxc/xc_domain_save.c
@@ -804,7 +804,8 @@ static int save_tsc_info(xc_interface *x
 
 int xc_domain_save(xc_interface *xch, int io_fd, uint32_t dom, uint32_t max_iters,
                    uint32_t max_factor, uint32_t flags,
-                   struct save_callbacks* callbacks, int hvm)
+                   struct save_callbacks* callbacks, int hvm,
+                   unsigned long vm_generationid_addr)
 {
     xc_dominfo_t info;
     DECLARE_DOMCTL;

@@ -1616,6 +1617,16 @@ int xc_domain_save(xc_interface *xch, in
             uint64_t data;
         } chunk = { 0, };
 
+        chunk.id = XC_SAVE_ID_HVM_GENERATION_ID_ADDR;
+        chunk.data = vm_generationid_addr;
+
+        if ( (chunk.data != 0) &&
+             wrexact(io_fd, &chunk, sizeof(chunk)) )
+        {
+            PERROR("Error when writing the generation id buffer location for guest");
+            goto out;
+        }
+
         chunk.id = XC_SAVE_ID_HVM_IDENT_PT;
         chunk.data = 0;
         xc_get_hvm_param(xch, dom, HVM_PARAM_IDENT_PT,

diff -r bd8e9eb71611 -r 5df9a24e0078 tools/libxc/xenguest.h
@@ -58,7 +58,8 @@ struct save_callbacks {
  */
 int xc_domain_save(xc_interface *xch, int io_fd, uint32_t dom, uint32_t max_iters,
                    uint32_t max_factor, uint32_t flags /* XCFLAGS_xxx */,
-                   struct save_callbacks* callbacks, int hvm);
+                   struct save_callbacks* callbacks, int hvm,
+                   unsigned long vm_generationid_addr);
 
 
 /**

@@ -72,12 +73,16 @@ int xc_domain_save(xc_interface *xch, in
  * @parm hvm non-zero if this is a HVM restore
  * @parm pae non-zero if this HVM domain has PAE support enabled
  * @parm superpages non-zero to allocate guest memory with superpages
+ * @parm no_incr_generationid non-zero if generation id is NOT to be incremented
+ * @parm vm_generationid_addr returned with the address of the generation id buffer
  * @return 0 on success, -1 on failure
  */
 int xc_domain_restore(xc_interface *xch, int io_fd, uint32_t dom,
                       unsigned int store_evtchn, unsigned long *store_mfn,
                       unsigned int console_evtchn, unsigned long *console_mfn,
-                      unsigned int hvm, unsigned int pae, int superpages);
+                      unsigned int hvm, unsigned int pae, int superpages,
+                      int no_incr_generationid,
+		      unsigned long *vm_generationid_addr);
 /**
  * xc_domain_restore writes a file to disk that contains the device
  * model saved state.

diff -r bd8e9eb71611 -r 5df9a24e0078 tools/libxc/xg_save_restore.h
@@ -253,6 +253,7 @@
 #define XC_SAVE_ID_HVM_VIRIDIAN       -11
 #define XC_SAVE_ID_COMPRESSED_DATA    -12 /* Marker to indicate arrival of compressed data */
 #define XC_SAVE_ID_ENABLE_COMPRESSION -13 /* Marker to enable compression logic at receiver side */
+#define XC_SAVE_ID_HVM_GENERATION_ID_ADDR -14
 
 /*
 ** We process save/restore/migrate in batches of pages; the below

diff -r bd8e9eb71611 -r 5df9a24e0078 tools/libxl/libxl_create.c
@@ -99,6 +99,7 @@ int libxl_init_build_info(libxl_ctx *ctx
         b_info->u.hvm.vpt_align = 1;
         b_info->u.hvm.timer_mode = 1;
         b_info->u.hvm.nested_hvm = 0;
+        b_info->u.hvm.no_incr_generationid = 0;
         break;
     case LIBXL_DOMAIN_TYPE_PV:
         b_info->u.pv.slack_memkb = 8 * 1024;

diff -r bd8e9eb71611 -r 5df9a24e0078 tools/libxl/libxl_dom.c
@@ -106,6 +106,7 @@ int libxl__build_pre(libxl__gc *gc, uint
 
     state->store_port = xc_evtchn_alloc_unbound(ctx->xch, domid, 0);
     state->console_port = xc_evtchn_alloc_unbound(ctx->xch, domid, 0);
+    state->vm_generationid_addr = 0;
     return 0;
 }
 

@@ -117,7 +118,7 @@ int libxl__build_post(libxl__gc *gc, uin
     libxl_ctx *ctx = libxl__gc_owner(gc);
     char *dom_path, *vm_path;
     xs_transaction_t t;
-    char **ents;
+    char **ents, **hvm_ents;
     int i;
 
     libxl_cpuid_apply_policy(ctx, domid);

@@ -143,6 +144,13 @@ int libxl__build_post(libxl__gc *gc, uin
                             ? "offline" : "online";
     }
 
+    hvm_ents = NULL;
+    if (info->type == LIBXL_DOMAIN_TYPE_HVM) {
+        hvm_ents = libxl__calloc(gc, 3, sizeof(char *));
+        hvm_ents[0] = "hvmloader/generation-id-address";
+        hvm_ents[1] = libxl__sprintf(gc, "0x%lx", state->vm_generationid_addr);
+    }
+
     dom_path = libxl__xs_get_dompath(gc, domid);
     if (!dom_path) {
         return ERROR_FAIL;

@@ -153,6 +161,9 @@ retry_transaction:
     t = xs_transaction_start(ctx->xsh);
 
     libxl__xs_writev(gc, t, dom_path, ents);
+    if (info->type == LIBXL_DOMAIN_TYPE_HVM)
+        libxl__xs_writev(gc, t, dom_path, hvm_ents);
+
     libxl__xs_writev(gc, t, dom_path, local_ents);
     libxl__xs_writev(gc, t, vm_path, vms_ents);
 

@@ -356,16 +367,19 @@ int libxl__domain_restore_common(libxl__
     /* read signature */
     int rc;
     int hvm, pae, superpages;
+    int no_incr_generationid;
     switch (info->type) {
     case LIBXL_DOMAIN_TYPE_HVM:
         hvm = 1;
         superpages = 1;
         pae = info->u.hvm.pae;
+        no_incr_generationid = info->u.hvm.no_incr_generationid;
         break;
     case LIBXL_DOMAIN_TYPE_PV:
         hvm = 0;
         superpages = 0;
         pae = 1;
+        no_incr_generationid = 0;
         break;
     default:
         return ERROR_INVAL;

@@ -373,7 +387,8 @@ int libxl__domain_restore_common(libxl__
     rc = xc_domain_restore(ctx->xch, fd, domid,
                            state->store_port, &state->store_mfn,
                            state->console_port, &state->console_mfn,
-                           hvm, pae, superpages);
+                           hvm, pae, superpages, no_incr_generationid,
+                           &state->vm_generationid_addr);
     if ( rc ) {
         LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR, "restoring domain");
         return ERROR_FAIL;

@@ -539,12 +554,23 @@ int libxl__domain_suspend_common(libxl__
     struct save_callbacks callbacks;
     struct suspendinfo si;
     int hvm, rc = ERROR_FAIL;
+    unsigned long vm_generationid_addr;
 
     switch (type) {
-    case LIBXL_DOMAIN_TYPE_HVM:
+    case LIBXL_DOMAIN_TYPE_HVM: {
+        char *path;
+        char *addr;
+
+        path = libxl__sprintf(gc, "%s/hvmloader/generation-id-address",
+                              libxl__xs_get_dompath(gc, domid));
+        addr = libxl__xs_read(gc, XBT_NULL, path);
+
+        vm_generationid_addr = (addr) ? strtoul(addr, NULL, 0) : 0;
         hvm = 1;
         break;
+    }
     case LIBXL_DOMAIN_TYPE_PV:
+        vm_generationid_addr = 0;
         hvm = 0;
         break;
     default:

@@ -582,7 +608,8 @@ int libxl__domain_suspend_common(libxl__
     callbacks.switch_qemu_logdirty = libxl__domain_suspend_common_switch_qemu_logdirty;
     callbacks.data = &si;
 
-    rc = xc_domain_save(ctx->xch, fd, domid, 0, 0, flags, &callbacks, hvm);
+    rc = xc_domain_save(ctx->xch, fd, domid, 0, 0, flags, &callbacks,
+                        hvm, vm_generationid_addr);
     if ( rc ) {
         LIBXL__LOG_ERRNO(ctx, LIBXL__LOG_ERROR, "saving domain: %s",
                          si.guest_responded ?

diff -r bd8e9eb71611 -r 5df9a24e0078 tools/libxl/libxl_internal.h
@@ -221,6 +221,7 @@ typedef struct {
 
     uint32_t console_port;
     unsigned long console_mfn;
+    unsigned long vm_generationid_addr;
 } libxl__domain_build_state;
 
 _hidden int libxl__build_pre(libxl__gc *gc, uint32_t domid,

diff -r bd8e9eb71611 -r 5df9a24e0078 tools/libxl/xl_cmdimpl.c
@@ -360,6 +360,8 @@ static void printf_info(int domid,
         printf("\t\t\t(vpt_align %d)\n", b_info->u.hvm.vpt_align);
         printf("\t\t\t(timer_mode %d)\n", b_info->u.hvm.timer_mode);
         printf("\t\t\t(nestedhvm %d)\n", b_info->u.hvm.nested_hvm);
+        printf("\t\t\t(no_incr_generationid %d)\n",
+                    b_info->u.hvm.no_incr_generationid);
 
         printf("\t\t\t(device_model %s)\n", dm_info->device_model ? : "default");
         printf("\t\t\t(videoram %d)\n", dm_info->videoram);

@@ -1362,6 +1364,7 @@ struct domain_create {
     const char *restore_file;
     int migrate_fd; /* -1 means none */
     char **migration_domname_r; /* from malloc */
+    int no_incr_generationid;
 };
 
 static int freemem(libxl_domain_build_info *b_info, libxl_device_model_info *dm_info)

@@ -1575,6 +1578,8 @@ static int create_domain(struct domain_c
         }
     }
 
+    d_config.b_info.u.hvm.no_incr_generationid = dom_info->no_incr_generationid;
+
     if (debug || dom_info->dryrun)
         printf_info(-1, &d_config, &d_config.dm_info);
 

@@ -2800,6 +2805,7 @@ static void migrate_receive(int debug, i
     dom_info.restore_file = "incoming migration stream";
     dom_info.migrate_fd = 0; /* stdin */
     dom_info.migration_domname_r = &migration_domname;
+    dom_info.no_incr_generationid = 1;
 
     rc = create_domain(&dom_info);
     if (rc < 0) {

diff -r bd8e9eb71611 -r 5df9a24e0078 tools/python/xen/lowlevel/checkpoint/libcheckpoint.c
@@ -175,6 +175,7 @@ int checkpoint_start(checkpoint_state* s
 {
     int hvm, rc;
     int flags = XCFLAGS_LIVE;
+    unsigned long vm_generationid_addr;
 
     if (!s->domid) {
        s->errstr = "checkpoint state not opened";

@@ -185,16 +186,28 @@ int checkpoint_start(checkpoint_state* s
 
     hvm = s->domtype > dt_pv;
     if (hvm) {
+       char path[128];
+       char *addr;
+
+       sprintf(path, "/local/domain/%u/hvmloader/generation-id-address", s->domid);
+       addr = xs_read(s->xsh, XBT_NULL, path, NULL);
+
+       vm_generationid_addr = (addr) ? strtoul(addr, NULL, 0) : 0;
+       free(addr);
+
        flags |= XCFLAGS_HVM;
        if (switch_qemu_logdirty(s, 1))
            return -1;
+    } else {
+       vm_generationid_addr = 0;
     }
     if (remus_flags & CHECKPOINT_FLAGS_COMPRESSION)
       flags |= XCFLAGS_CHECKPOINT_COMPRESS;
 
     callbacks->switch_qemu_logdirty = noop_switch_logdirty;
 
-    rc = xc_domain_save(s->xch, fd, s->domid, 0, 0, flags, callbacks, hvm);
+    rc = xc_domain_save(s->xch, fd, s->domid, 0, 0, flags, callbacks, hvm,
+                        vm_generationid_addr);
 
     if (hvm)
        switch_qemu_logdirty(s, 0);

diff -r bd8e9eb71611 -r 5df9a24e0078 tools/xcutils/xc_restore.c
@@ -46,7 +46,8 @@ main(int argc, char **argv)
 	    superpages = !!hvm;
 
     ret = xc_domain_restore(xch, io_fd, domid, store_evtchn, &store_mfn,
-                            console_evtchn, &console_mfn, hvm, pae, superpages);
+                            console_evtchn, &console_mfn, hvm, pae, superpages,
+                            0, NULL);
 
     if ( ret == 0 )
     {

diff -r bd8e9eb71611 -r 5df9a24e0078 tools/xcutils/xc_save.c
@@ -208,7 +208,7 @@ main(int argc, char **argv)
     callbacks.suspend = suspend;
     callbacks.switch_qemu_logdirty = switch_qemu_logdirty;
     ret = xc_domain_save(si.xch, io_fd, si.domid, maxit, max_f, si.flags, 
-                         &callbacks, !!(si.flags & XCFLAGS_HVM));
+                         &callbacks, !!(si.flags & XCFLAGS_HVM), 0);
 
     if (si.suspend_evtchn > 0)
 	 xc_suspend_evtchn_release(si.xch, si.xce, si.domid, si.suspend_evtchn);