Passing multiple modules to Domain0

diff -r 08e010c3f251 xen/arch/x86/domain_build.c
@@ -193,10 +193,104 @@ static void __init process_dom0_ioports_
     }
 }
 
+unsigned long __init modules_size(v_module_t *mods,
+                                  unsigned int mods_start,
+                                  unsigned int mods_end,
+                                  int multimodules,
+                                  int physical)
+{
+    unsigned long mods_size;
+    unsigned int i;
+
+    mods_size = mods_end > mods_start ?
+                  mods[mods_end-1].mod_end - mods[mods_start].mod_start : 0;
+    if ( multimodules )
+    {
+        /* Add space for module strings and a v_module_t array */
+        for ( i = mods_start; i < mods_end; i++ ) {
+            mods_size += mods[i].string
+                ? strlen(physical ? (char*)__va(mods[i].string)
+                                  : (char*)mods[i].string) + 1
+                : 0;
+            mods_size += sizeof(v_module_t);
+        }
+    }
+    return mods_size;
+}
+
+static unsigned long __init get_virtual(int physical, unsigned long addr)
+{
+    return physical ? (unsigned long)maddr_to_bootstrap_virt(addr) : addr;
+}
+
+v_module_t * __init copy_modules(unsigned long _dest,
+                                 v_module_t *mods,
+                                 unsigned int mods_start,
+                                 unsigned int mods_end,
+                                 int multimodules,
+                                 int physical)
+{
+    unsigned long dest = get_virtual(physical, _dest);
+    unsigned long len = mods[mods_end-1].mod_end - mods[mods_start].mod_start;
+    v_module_t *newmods = 0;
+
+    if ( multimodules )
+    {
+        /* Check that source and destination don't overlap in a way that
+         * causes us to step on the source as we copy, because we aren't
+         * clever enough to handle that. */
+        unsigned long mods_size = modules_size(mods, mods_start, mods_end,
+                                               multimodules, physical);
+        unsigned long source = get_virtual(physical, mods[0].mod_start);
+        BUG_ON(dest >= source && dest < source+mods_size);
+    }
+
+    if ( physical )
+        move_memory(_dest, mods[mods_start].mod_start, mods[mods_end-1].mod_end);
+    else
+        memcpy((void*)dest,
+               (void*)(get_virtual(physical, mods[mods_start].mod_start)), len);
+
+    if ( multimodules )
+    {
+        /* Create module array and copy strings */
+        v_module_t *p = (v_module_t*) ((char *)dest + len);
+        char *strings;
+        int i;
+
+        newmods = p;
+        for (i = mods_start; i < mods_end; i++,p++)
+        {
+            p->mod_start = dest + mods[i].mod_start
+                                - mods[mods_start].mod_start;
+            p->mod_end = dest + mods[i].mod_end - mods[mods_start].mod_start;
+        }
+        strings = (char*)p;
+        p = newmods;
+        for (i = mods_start; i < mods_end; i++, p++)
+        {
+            if (mods[i].string)
+            {
+                p->string = (unsigned long)strings;
+                strlcpy(strings, (physical ? __va(mods[i].string)
+                                           : (char*)mods[i].string),
+                        MAX_GUEST_CMDLINE);
+                strings += strlen(strings) + 1;
+            } else {
+                p->string = 0;
+            }
+        }
+    }
+    return newmods;
+}
+
 int __init construct_dom0(
     struct domain *d,
-    unsigned long _image_start, unsigned long image_len,
-    unsigned long _initrd_start, unsigned long initrd_len,
+    unsigned long _image_start,
+    int multimodules,
+    v_module_t *mods,
+    unsigned int mods_start,
+    unsigned int mods_end,
     char *cmdline)
 {
     int i, rc, compatible, compat32, order, machine;

@@ -207,17 +301,13 @@ int __init construct_dom0(
     unsigned long alloc_spfn;
     unsigned long alloc_epfn;
     unsigned long count;
+    unsigned long mods_size;
+    unsigned long initrd_len;
     struct page_info *page = NULL;
     start_info_t *si;
     struct vcpu *v = d->vcpu[0];
     unsigned long long value;
-#if defined(__i386__)
-    char *image_start  = (char *)_image_start;  /* use lowmem mappings */
-    char *initrd_start = (char *)_initrd_start; /* use lowmem mappings */
-#elif defined(__x86_64__)
-    char *image_start  = __va(_image_start);
-    char *initrd_start = __va(_initrd_start);
-#endif
+    char *image_start = maddr_to_bootstrap_virt((char*)_image_start);
 #if CONFIG_PAGING_LEVELS >= 4
     l4_pgentry_t *l4tab = NULL, *l4start = NULL;
 #endif

@@ -263,7 +353,10 @@ int __init construct_dom0(
 
     nr_pages = compute_dom0_nr_pages();
 
-    if ( (rc = elf_init(&elf, image_start, image_len)) != 0 )
+    mods_size = modules_size(mods, mods_start, mods_end, multimodules, 0);
+
+    if ( (rc = elf_init(&elf, image_start,
+                        mods[0].mod_end - mods[0].mod_start)) != 0 )
         return rc;
 #ifdef VERBOSE
     elf_set_verbose(&elf);

@@ -380,7 +473,7 @@ int __init construct_dom0(
     vkern_start      = parms.virt_kstart;
     vkern_end        = parms.virt_kend;
     vinitrd_start    = round_pgup(vkern_end);
-    vinitrd_end      = vinitrd_start + initrd_len;
+    vinitrd_end      = vinitrd_start + mods_size;
     vphysmap_start   = round_pgup(vinitrd_end);
     vphysmap_end     = vphysmap_start + (nr_pages * (!is_pv_32on64_domain(d) ?
                                                      sizeof(unsigned long) :

@@ -803,9 +896,17 @@ int __init construct_dom0(
         hypercall_page_initialise(d, (void *)(unsigned long)parms.virt_hypercall);
     }
 
-    /* Copy the initial ramdisk. */
-    if ( initrd_len != 0 )
-        memcpy((void *)vinitrd_start, initrd_start, initrd_len);
+    initrd_len = mods_size;
+
+    if ( mods_size != 0 ) {
+        v_module_t *newmods = copy_modules(vinitrd_start, mods, mods_start,
+                                           mods_end, multimodules, 0);
+        if ( multimodules )
+        {
+            vinitrd_start = (unsigned long)newmods;
+            initrd_len = mods_end - mods_start;
+        }
+    }
 
     /* Free temporary buffers. */
     discard_initial_images();

119 lines not on this page · raw message

diff -r 08e010c3f251 xen/include/asm-x86/page.h
@@ -248,6 +248,12 @@ void clear_page_sse2(void *);
 #define pfn_to_paddr(pfn)   ((paddr_t)(pfn) << PAGE_SHIFT)
 #define paddr_to_pfn(pa)    ((unsigned long)((pa) >> PAGE_SHIFT))
 
+#if defined(CONFIG_X86_64)
+#define maddr_to_bootstrap_virt(m) maddr_to_virt(m)
+#else
+#define maddr_to_bootstrap_virt(m) ((void *)(long)(m))
+#endif
+
 #endif /* !defined(__ASSEMBLY__) */
 
 /* High table entries are reserved by the hypervisor. */

diff -r 08e010c3f251 xen/include/public/xen.h
@@ -541,11 +541,23 @@ struct start_info {
     unsigned long pt_base;      /* VIRTUAL address of page directory.     */
     unsigned long nr_pt_frames; /* Number of bootstrap p.t. frames.       */
     unsigned long mfn_list;     /* VIRTUAL address of page-frame list.    */
-    unsigned long mod_start;    /* VIRTUAL address of pre-loaded module.  */
-    unsigned long mod_len;      /* Size (bytes) of pre-loaded module.     */
+    unsigned long mod_start;    /* VIRTUAL address of pre-loaded module,  */
+                                /* or VIRTUAL address of v_module_t array.*/
+    unsigned long mod_len;      /* Size (bytes) of pre-loaded module,     */
+                                /* or length of v_module_t array.         */
     int8_t cmd_line[MAX_GUEST_CMDLINE];
 };
 typedef struct start_info start_info_t;
+
+/* This corresponds to module_t in multiboot.h, but with virtual
+ * addresses.
+ */
+struct v_module {
+    unsigned long mod_start;
+    unsigned long mod_end;
+    unsigned long string;
+};
+typedef struct v_module v_module_t;
 
 /* New console union for dom0 introduced in 0x00030203. */
 #if __XEN_INTERFACE_VERSION__ < 0x00030203

diff -r 08e010c3f251 xen/include/xen/sched.h
@@ -315,11 +315,38 @@ struct domain *domain_create(
 #define _DOMCRF_hap 1
 #define DOMCRF_hap  (1U<<_DOMCRF_hap)
 
+/* Compute size of all modules in mods, starting from mods_start,
+ * ending at mods_end - 1. Include size of module parameters and mods
+ * array itself if multimodules is set. If physical is set, assume
+ * physical addresses. */
+unsigned long modules_size(v_module_t *mods,
+                                  unsigned int mods_start,
+                                  unsigned int mods_end,
+                                  int multimodules,
+                                  int physical);
+
+/* Copy all modules in mods, starting from mods_start, ending at
+ * mods_end - 1, into dest. Copy module parameters and mods array
+ * itself if multimodules is set. If physical is set, assume physical
+ * addresses. */
+v_module_t *copy_modules(unsigned long dest,
+                         v_module_t *mods,
+                         unsigned int mods_start,
+                         unsigned int mods_end,
+                         int multimodules,
+                         int physical);
+
 int construct_dom0(
     struct domain *d,
-    unsigned long image_start, unsigned long image_len,
-    unsigned long initrd_start, unsigned long initrd_len,
+    unsigned long image_start,
+    int multimodules,
+    v_module_t *mods,
+    unsigned int mods_start,
+    unsigned int mods_end,
     char *cmdline);
+
+void move_memory(unsigned long dst,
+                 unsigned long src_start, unsigned long src_end);
 
 /*
  * rcu_lock_domain_by_id() is more efficient than get_domain_by_id().