Xen 4.0 backport of cs 23420-23423

diff -r 30c9bcaec782 -r b2d7c4238c2f tools/libxc/xc_domain_restore.c
@@ -45,6 +45,11 @@ struct restore_ctx {
 };
 
 #define HEARTBEAT_MS 1000
+
+#define SUPERPAGE_PFN_SHIFT  9
+#define SUPERPAGE_NR_PFNS    (1UL << SUPERPAGE_PFN_SHIFT)
+
+#define SUPER_PAGE_START(pfn)    (((pfn) & (SUPERPAGE_NR_PFNS-1)) == 0 )
 
 #ifndef __MINIOS__
 static ssize_t read_exact_timed(struct restore_ctx *ctx,

@@ -800,9 +805,11 @@ static int apply_batch(int xc_handle, ui
 static int apply_batch(int xc_handle, uint32_t dom, struct restore_ctx *ctx,
                        xen_pfn_t* region_mfn, unsigned long* pfn_type, int pae_extended_cr3,
                        unsigned int hvm, struct xc_mmu* mmu,
-                       pagebuf_t* pagebuf, int curbatch)
+                       pagebuf_t* pagebuf, int curbatch, int superpages)
 {
     int i, j, curpage, nr_mfns;
+    int k, scount;
+    unsigned long superpage_start=INVALID_P2M_ENTRY;
     /* used by debug verify code */
     unsigned long buf[PAGE_SIZE/sizeof(unsigned long)];
     /* Our mapping of the current region (batch) */

@@ -820,8 +827,8 @@ static int apply_batch(int xc_handle, ui
     if (j > MAX_BATCH_SIZE)
         j = MAX_BATCH_SIZE;
 
-    /* First pass for this batch: work out how much memory to alloc */
-    nr_mfns = 0; 
+    /* First pass for this batch: work out how much memory to alloc, and detect superpages */
+    nr_mfns = scount = 0;
     for ( i = 0; i < j; i++ )
     {
         unsigned long pfn, pagetype;

@@ -832,19 +839,103 @@ static int apply_batch(int xc_handle, ui
              (ctx->p2m[pfn] == INVALID_P2M_ENTRY) )
         {
             /* Have a live PFN which hasn't had an MFN allocated */
+ 
+             /* Logic if we're in the middle of detecting a candidate superpage */
+             if ( superpage_start != INVALID_P2M_ENTRY )
+             {
+                 /* Is this the next expected continuation? */
+                 if ( pfn == superpage_start + scount )
+                 {
+                     if ( !superpages )
+                     {
+                         ERROR("Unexpexted codepath with no superpages");
+                         return -1;
+                     }
+ 
+                     scount++;
+ 
+                     /* If we've found a whole superpage, allocate it and update p2m */
+                     if ( scount  == SUPERPAGE_NR_PFNS )
+                     {
+                         unsigned long supermfn;
+ 
+ 
+                         supermfn=superpage_start;
+                         if ( xc_domain_memory_populate_physmap(xc_handle, dom, 1,
+                                          SUPERPAGE_PFN_SHIFT, 0, &supermfn) != 0 )
+                         {
+                             DPRINTF("No 2M page available for pfn 0x%lx, fall back to 4K page.\n",
+                                     superpage_start);
+                             /* If we're falling back from a failed allocation, subtract one
+                              * from count, since the last page == pfn, which will behandled
+                              * anyway. */
+                             scount--;
+                             goto fallback;
+                         }
+ 
+                         DPRINTF("Mapping superpage (%d) pfn %lx, mfn %lx\n", scount, superpage_start, supermfn);
+                         for (k=0; k<scount; k++)
+                         {
+                             /* We just allocated a new mfn above; update p2m */
+                             ctx->p2m[superpage_start+k] = supermfn+k;
+                             ctx->nr_pfns++;
+                             /* region_map[] will be set below */
+                         }
+                         superpage_start=INVALID_P2M_ENTRY;
+                         scount=0;
+                     }
+                     continue;
+                 }
+                 
+             fallback:
+                 DPRINTF("Falling back %d pages pfn %lx\n", scount, superpage_start);
+                 for (k=0; k<scount; k++)
+                 {
+                     ctx->p2m_batch[nr_mfns++] = superpage_start+k; 
+                     ctx->p2m[superpage_start+k]--;
+                 }
+                 superpage_start = INVALID_P2M_ENTRY;
+                 scount=0;
+             }
+ 
+             /* Are we ready to start a new superpage candidate? */
+             if ( superpages && SUPER_PAGE_START(pfn) )
+             {
+                 superpage_start=pfn;
+                 scount++;
+                 continue;
+             }
+             
+             /* Add the current pfn to pfn_batch */
             ctx->p2m_batch[nr_mfns++] = pfn; 
             ctx->p2m[pfn]--;
         }
-    } 
+     }
+ 
+     /* Clean up any partial superpage candidates */
+     if ( superpage_start != INVALID_P2M_ENTRY )
+     {
+         DPRINTF("Falling back %d pages pfn %lx\n", scount, superpage_start);
+         for (k=0; k<scount; k++)
+         {
+             ctx->p2m_batch[nr_mfns++] = superpage_start+k; 
+             ctx->p2m[superpage_start+k]--;
+         }
+         superpage_start = INVALID_P2M_ENTRY;
+     }
 
     /* Now allocate a bunch of mfns for this batch */
-    if ( nr_mfns &&
-         (xc_domain_memory_populate_physmap(xc_handle, dom, nr_mfns, 0,
-                                            0, ctx->p2m_batch) != 0) )
-    { 
-        ERROR("Failed to allocate memory for batch.!\n"); 
-        errno = ENOMEM;
-        return -1;
+     if ( nr_mfns )
+     {
+         DPRINTF("Mapping order 0,  %d; first pfn %lx\n", nr_mfns, ctx->p2m_batch[0]);
+     
+         if(xc_domain_memory_populate_physmap(xc_handle, dom, nr_mfns, 0,
+                                             0, ctx->p2m_batch) != 0) 
+         { 
+             ERROR("Failed to allocate memory for batch.!\n"); 
+             errno = ENOMEM;
+             return -1;
+         }
     }
 
     /* Second pass for this batch: update p2m[] and region_mfn[] */

@@ -895,7 +986,8 @@ static int apply_batch(int xc_handle, ui
 
         if (pfn_err[i])
         {
-            ERROR("unexpected PFN mapping failure");
+            ERROR("unexpected PFN mapping failure pfn %lx map_mfn %lx p2m_mfn %lx",
+                  pfn, region_mfn[i], ctx->p2m[pfn]);
             goto err_mapped;
         }
 

@@ -1058,9 +1150,6 @@ int xc_domain_restore(int xc_handle, int
     /* For info only */
     ctx->nr_pfns = 0;
 
-    if ( superpages )
-        return 1;
-
     if ( read_exact(io_fd, &dinfo->p2m_size, sizeof(unsigned long)) )
     {
         ERROR("read: p2m_size");

@@ -1209,7 +1298,8 @@ int xc_domain_restore(int xc_handle, int
             int brc;
 
             brc = apply_batch(xc_handle, dom, ctx, region_mfn, pfn_type,
-                              pae_extended_cr3, hvm, mmu, &pagebuf, curbatch);
+                              pae_extended_cr3, hvm, mmu, &pagebuf, curbatch,
+                              superpages);
             if ( brc < 0 )
                 goto out;
 

diff -r b2d7c4238c2f -r 8b1e10c2494f tools/libxc/xc_domain_save.c
@@ -67,6 +67,11 @@ struct outbuf {
     (((_mfn) < (ctx->max_mfn)) &&                \
      ((mfn_to_pfn(_mfn) < (dinfo->p2m_size)) &&   \
       (pfn_to_mfn(mfn_to_pfn(_mfn)) == (_mfn))))
+
+#define SUPERPAGE_PFN_SHIFT  9
+#define SUPERPAGE_NR_PFNS    (1UL << SUPERPAGE_PFN_SHIFT)
+
+#define SUPER_PAGE_START(pfn)    (((pfn) & (SUPERPAGE_NR_PFNS-1)) == 0 )
 
 /*
 ** During (live) save/migrate, we maintain a number of bitmaps to track

@@ -866,6 +871,7 @@ int xc_domain_save(int xc_handle, int io
     int rc = 1, frc, i, j, last_iter = 0, iter = 0;
     int live  = (flags & XCFLAGS_LIVE);
     int debug = (flags & XCFLAGS_DEBUG);
+    int superpages = !!hvm;
     int race = 0, sent_last_iter, skip_this_iter;
     int tmem_saved = 0;
 

@@ -1228,6 +1234,12 @@ int xc_domain_save(int xc_handle, int io
                            (test_bit(n, to_fix)  && last_iter)) )
                         continue;
 
+                    /* First time through, try to keep superpages in the same batch */
+                    if ( superpages && iter == 1
+                         && SUPER_PAGE_START(n)
+                         && batch + SUPERPAGE_NR_PFNS > MAX_BATCH_SIZE )
+                        break;
+
                     /*
                     ** we get here if:
                     **  1. page is marked to_send & hasn't already been re-dirtied

diff -r 8b1e10c2494f -r 7bf9266bc106 tools/libxc/xc_domain_restore.c
@@ -757,7 +757,8 @@ static int pagebuf_get_one(struct restor
 
     countpages = count;
     for (i = oldcount; i < buf->nr_pages; ++i)
-        if ((buf->pfn_types[i] & XEN_DOMCTL_PFINFO_LTAB_MASK) == XEN_DOMCTL_PFINFO_XTAB)
+        if ((buf->pfn_types[i] & XEN_DOMCTL_PFINFO_LTAB_MASK) == XEN_DOMCTL_PFINFO_XTAB
+            ||(buf->pfn_types[i] & XEN_DOMCTL_PFINFO_LTAB_MASK) == XEN_DOMCTL_PFINFO_XALLOC)
             --countpages;
 
     if (!countpages)

@@ -835,6 +836,7 @@ static int apply_batch(int xc_handle, ui
         pfn      = pagebuf->pfn_types[i + curbatch] & ~XEN_DOMCTL_PFINFO_LTAB_MASK;
         pagetype = pagebuf->pfn_types[i + curbatch] &  XEN_DOMCTL_PFINFO_LTAB_MASK;
 
+        /* For allocation purposes, treat XEN_DOMCTL_PFINFO_XALLOC as a normal page */
         if ( (pagetype != XEN_DOMCTL_PFINFO_XTAB) && 
              (ctx->p2m[pfn] == INVALID_P2M_ENTRY) )
         {

@@ -946,21 +948,21 @@ static int apply_batch(int xc_handle, ui
         pfn      = pagebuf->pfn_types[i + curbatch] & ~XEN_DOMCTL_PFINFO_LTAB_MASK;
         pagetype = pagebuf->pfn_types[i + curbatch] &  XEN_DOMCTL_PFINFO_LTAB_MASK;
 
-        if ( pagetype == XEN_DOMCTL_PFINFO_XTAB )
+        if ( pagetype != XEN_DOMCTL_PFINFO_XTAB
+             && ctx->p2m[pfn] == (INVALID_P2M_ENTRY-1) )
+        {
+            /* We just allocated a new mfn above; update p2m */
+            ctx->p2m[pfn] = ctx->p2m_batch[nr_mfns++]; 
+            ctx->nr_pfns++; 
+        }
+
+        /* setup region_mfn[] for batch map, if necessary.
+         * For HVM guests, this interface takes PFNs, not MFNs */
+        if ( pagetype == XEN_DOMCTL_PFINFO_XTAB
+             || pagetype == XEN_DOMCTL_PFINFO_XALLOC )
             region_mfn[i] = ~0UL; /* map will fail but we don't care */
-        else 
-        {
-            if ( ctx->p2m[pfn] == (INVALID_P2M_ENTRY-1) )
-            {
-                /* We just allocated a new mfn above; update p2m */
-                ctx->p2m[pfn] = ctx->p2m_batch[nr_mfns++]; 
-                ctx->nr_pfns++; 
-            }
-
-            /* setup region_mfn[] for batch map.
-             * For HVM guests, this interface takes PFNs, not MFNs */
+        else
             region_mfn[i] = hvm ? pfn : ctx->p2m[pfn]; 
-        }
     }
 
     /* Map relevant mfns */

@@ -980,8 +982,9 @@ static int apply_batch(int xc_handle, ui
         pfn      = pagebuf->pfn_types[i + curbatch] & ~XEN_DOMCTL_PFINFO_LTAB_MASK;
         pagetype = pagebuf->pfn_types[i + curbatch] &  XEN_DOMCTL_PFINFO_LTAB_MASK;
 
-        if ( pagetype == XEN_DOMCTL_PFINFO_XTAB )
-            /* a bogus/unmapped page: skip it */
+        if ( pagetype == XEN_DOMCTL_PFINFO_XTAB 
+             || pagetype == XEN_DOMCTL_PFINFO_XALLOC)
+            /* a bogus/unmapped/allocate-only page: skip it */
             continue;
 
         if (pfn_err[i])

150 lines not on this page · raw message

diff -r 8b1e10c2494f -r 7bf9266bc106 xen/include/public/domctl.h
@@ -137,6 +137,7 @@ DEFINE_XEN_GUEST_HANDLE(xen_domctl_getme
 #define XEN_DOMCTL_PFINFO_LTABTYPE_MASK (0x7U<<28)
 #define XEN_DOMCTL_PFINFO_LPINTAB (0x1U<<31)
 #define XEN_DOMCTL_PFINFO_XTAB    (0xfU<<28) /* invalid page */
+#define XEN_DOMCTL_PFINFO_XALLOC  (0xeU<<28) /* allocate-only page */
 #define XEN_DOMCTL_PFINFO_PAGEDTAB (0x8U<<28)
 #define XEN_DOMCTL_PFINFO_LTAB_MASK (0xfU<<28)
 

diff -r 7bf9266bc106 -r 1d7a98073b7d tools/libxl/libxl_dom.c
@@ -192,7 +192,7 @@ int restore_common(struct libxl_ctx *ctx
     return xc_domain_restore(ctx->xch, fd, domid,
                              state->store_port, &state->store_mfn,
                              state->console_port, &state->console_mfn,
-                             info->hvm, info->u.hvm.pae, 0);
+                             info->hvm, info->u.hvm.pae, !!info->hvm);
 }
 
 struct suspendinfo {

diff -r 7bf9266bc106 -r 1d7a98073b7d tools/xcutils/xc_restore.c
@@ -42,7 +42,7 @@ main(int argc, char **argv)
     if ( argc == 9 )
 	    superpages = atoi(argv[8]);
     else
-	    superpages = 0;
+	    superpages = !!hvm;
 
     ret = xc_domain_restore(xc_fd, io_fd, domid, store_evtchn, &store_mfn,
                             console_evtchn, &console_mfn, hvm, pae, superpages);