Re: [Xen-devel] [v7][PATCH 07/16] hvmloader/e820: construct guest e820 table

2015-07-16 Thread George Dunlap
On Thu, Jul 16, 2015 at 2:58 AM, Chen, Tiejun tiejun.c...@intel.com wrote:
 I think I would say:

 --
 Now use the hypervisor-supplied memory map to build our final e820 table:
 * Add regions for BIOS ranges and other special mappings not in the
 hypervisor map
 * Add in the hypervisor regions
 * Adjust the lowmem and highmem regions if we've had to relocate
 memory (adding a highmem region if necessary)
 * Sort all the ranges so that they appear in memory order.
 --


 I'll update this and thanks a lot.



 CC: Keir Fraser k...@xen.org
 CC: Jan Beulich jbeul...@suse.com
 CC: Andrew Cooper andrew.coop...@citrix.com
 CC: Ian Jackson ian.jack...@eu.citrix.com
 CC: Stefano Stabellini stefano.stabell...@eu.citrix.com
 CC: Ian Campbell ian.campb...@citrix.com
 CC: Wei Liu wei.l...@citrix.com
 Signed-off-by: Tiejun Chen tiejun.c...@intel.com
 ---


 [snip]

 +/* Low RAM goes here. Reserve space for special pages. */
 +BUG_ON(low_mem_end  (2u  20));


 Won't this BUG if the guest was actually given less than 2GiB of RAM?


 2u  20 = 0x20, so this is 2M, not 2G :)

Oh, right. :-)

 -George

___
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel


Re: [Xen-devel] [v7][PATCH 07/16] hvmloader/e820: construct guest e820 table

2015-07-15 Thread Chen, Tiejun

I think I would say:

--
Now use the hypervisor-supplied memory map to build our final e820 table:
* Add regions for BIOS ranges and other special mappings not in the
hypervisor map
* Add in the hypervisor regions
* Adjust the lowmem and highmem regions if we've had to relocate
memory (adding a highmem region if necessary)
* Sort all the ranges so that they appear in memory order.
--


I'll update this and thanks a lot.





CC: Keir Fraser k...@xen.org
CC: Jan Beulich jbeul...@suse.com
CC: Andrew Cooper andrew.coop...@citrix.com
CC: Ian Jackson ian.jack...@eu.citrix.com
CC: Stefano Stabellini stefano.stabell...@eu.citrix.com
CC: Ian Campbell ian.campb...@citrix.com
CC: Wei Liu wei.l...@citrix.com
Signed-off-by: Tiejun Chen tiejun.c...@intel.com
---


[snip]


+/* Low RAM goes here. Reserve space for special pages. */
+BUG_ON(low_mem_end  (2u  20));


Won't this BUG if the guest was actually given less than 2GiB of RAM?


2u  20 = 0x20, so this is 2M, not 2G :)




+
+/*
+ * We may need to adjust real lowmem end since we may
+ * populate RAM to get enough MMIO previously.
+ */


[snip]


+
+/*
+ * And then we also need to adjust highmem.
+ */
+if ( add_high_mem )
+{
+for ( i = 0; i  memory_map.nr_map; i++ )
+{
+if ( e820[i].type == E820_RAM 
+ e820[i].addr  (1ull  32))
+e820[i].size += add_high_mem;
+}
+}


What if there was originally no high memory, but resizing the pci hole
meant we had to create a high memory region?



You're right. We need to consider this case.

Thanks
Tiejun


___
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel


Re: [Xen-devel] [v7][PATCH 07/16] hvmloader/e820: construct guest e820 table

2015-07-15 Thread George Dunlap
On Thu, Jul 9, 2015 at 6:33 AM, Tiejun Chen tiejun.c...@intel.com wrote:
 Now we can use that memory map to build our final
 e820 table but it may need to reorder all e820
 entries.

I think I would say:

--
Now use the hypervisor-supplied memory map to build our final e820 table:
* Add regions for BIOS ranges and other special mappings not in the
hypervisor map
* Add in the hypervisor regions
* Adjust the lowmem and highmem regions if we've had to relocate
memory (adding a highmem region if necessary)
* Sort all the ranges so that they appear in memory order.
--


 CC: Keir Fraser k...@xen.org
 CC: Jan Beulich jbeul...@suse.com
 CC: Andrew Cooper andrew.coop...@citrix.com
 CC: Ian Jackson ian.jack...@eu.citrix.com
 CC: Stefano Stabellini stefano.stabell...@eu.citrix.com
 CC: Ian Campbell ian.campb...@citrix.com
 CC: Wei Liu wei.l...@citrix.com
 Signed-off-by: Tiejun Chen tiejun.c...@intel.com
 ---
 v5 ~ v7:

 * Nothing is changed.

 v4:

 * Rename local variable, low_mem_pgend, to low_mem_end.

 * Improve some code comments

 * Adjust highmem after lowmem is changed.

  tools/firmware/hvmloader/e820.c | 80 
 +
  1 file changed, 66 insertions(+), 14 deletions(-)

 diff --git a/tools/firmware/hvmloader/e820.c b/tools/firmware/hvmloader/e820.c
 index 3e53c47..aa2569f 100644
 --- a/tools/firmware/hvmloader/e820.c
 +++ b/tools/firmware/hvmloader/e820.c
 @@ -108,7 +108,9 @@ int build_e820_table(struct e820entry *e820,
   unsigned int lowmem_reserved_base,
   unsigned int bios_image_base)
  {
 -unsigned int nr = 0;
 +unsigned int nr = 0, i, j;
 +uint64_t add_high_mem = 0;
 +uint64_t low_mem_end = hvm_info-low_mem_pgend  PAGE_SHIFT;

  if ( !lowmem_reserved_base )
  lowmem_reserved_base = 0xA;
 @@ -152,13 +154,6 @@ int build_e820_table(struct e820entry *e820,
  e820[nr].type = E820_RESERVED;
  nr++;

 -/* Low RAM goes here. Reserve space for special pages. */
 -BUG_ON((hvm_info-low_mem_pgend  PAGE_SHIFT)  (2u  20));
 -e820[nr].addr = 0x10;
 -e820[nr].size = (hvm_info-low_mem_pgend  PAGE_SHIFT) - e820[nr].addr;
 -e820[nr].type = E820_RAM;
 -nr++;
 -
  /*
   * Explicitly reserve space for special pages.
   * This space starts at RESERVED_MEMBASE an extends to cover various
 @@ -194,16 +189,73 @@ int build_e820_table(struct e820entry *e820,
  nr++;
  }

 -
 -if ( hvm_info-high_mem_pgend )
 +/*
 + * Construct E820 table according to recorded memory map.
 + *
 + * The memory map created by toolstack may include,
 + *
 + * #1. Low memory region
 + *
 + * Low RAM starts at least from 1M to make sure all standard regions
 + * of the PC memory map, like BIOS, VGA memory-mapped I/O and vgabios,
 + * have enough space.
 + *
 + * #2. Reserved regions if they exist
 + *
 + * #3. High memory region if it exists
 + */
 +for ( i = 0; i  memory_map.nr_map; i++ )
  {
 -e820[nr].addr = ((uint64_t)1  32);
 -e820[nr].size =
 -((uint64_t)hvm_info-high_mem_pgend  PAGE_SHIFT) - 
 e820[nr].addr;
 -e820[nr].type = E820_RAM;
 +e820[nr] = memory_map.map[i];
  nr++;
  }

 +/* Low RAM goes here. Reserve space for special pages. */
 +BUG_ON(low_mem_end  (2u  20));

Won't this BUG if the guest was actually given less than 2GiB of RAM?

 +
 +/*
 + * We may need to adjust real lowmem end since we may
 + * populate RAM to get enough MMIO previously.
 + */
 +for ( i = 0; i  memory_map.nr_map; i++ )
 +{
 +uint64_t end = e820[i].addr + e820[i].size;
 +if ( e820[i].type == E820_RAM 
 + low_mem_end  e820[i].addr  low_mem_end  end )
 +{
 +add_high_mem = end - low_mem_end;
 +e820[i].size = low_mem_end - e820[i].addr;
 +}
 +}
 +
 +/*
 + * And then we also need to adjust highmem.
 + */
 +if ( add_high_mem )
 +{
 +for ( i = 0; i  memory_map.nr_map; i++ )
 +{
 +if ( e820[i].type == E820_RAM 
 + e820[i].addr  (1ull  32))
 +e820[i].size += add_high_mem;
 +}
 +}

What if there was originally no high memory, but resizing the pci hole
meant we had to create a high memory region?

Other than those things, looks good.

 -George

___
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel


Re: [Xen-devel] [v7][PATCH 07/16] hvmloader/e820: construct guest e820 table

2015-07-14 Thread Chen, Tiejun

On 2015/7/14 17:32, Jan Beulich wrote:

On 14.07.15 at 07:22, tiejun.c...@intel.com wrote:
+for ( i = 0; i  memory_map.nr_map; i++ )
+{
+uint64_t end = e820[i].addr + e820[i].size;


Either loop index/boundary or used array are wrong here: In the
earlier loop you copied memory_map[0...nr_map-1] to
e820[n...n+nr_map-1], but here you're looping looking at
e820[0...nr_map-1]


You're right. I should lookup all e820[] like this,

for ( i = 0; i  nr; i++ )


Hmm, I would have thought you only care about either part of
the just glued together map.


+if ( e820[i].type == E820_RAM 
+ low_mem_end  e820[i].addr  low_mem_end  end )


Assuming you mean to look at the RDM e820[] entries here, this
is not a correct check: You don't care about partly or fully
contained, all you care about is whether low_mem_end extends
beyond the start of the region.


Here I'm looking at the e820 entry indicating low memory. Because

low_mem_end = hvm_info-low_mem_pgend  PAGE_SHIFT;

and when we allocate MMIO in pci.c, its possible to populate RAM so
hvm_info-low_mem_pgend would be changed over there. So we need to
compensate this loss with high memory. Here memory_map[] also records
the original low/high memory, so if low_mem_end is less-than the
original we need this compensation.


And I'm not disputing your intentions - I'm merely pointing out that
afaics the code above doesn't match these intentions. In particular
(as said) I don't see why you need to check low_mem_end  end.



Before we probably relocate RAM,

low_mem_end = hvm_info-low_mem_pgend  PAGE_SHIFT

and the e820 entry specific to low memory,

[e820[X].addr, end]

Here, end = e820[X].addr + e820[X].size;

Now low_mem_end = end.

After that, low_mem_end  end. so if

(low_mem_end  e820[X].addr  low_mem_end  end) is true, this means 
that associated RAM entry is hitting, right? Then we need to revise this 
entry as [e820[X].addr, low_mem_end], and compensate [end - low_mem_end] 
to high memory. Anything I'm still wrong here?


Thanks
Tiejun

___
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel


Re: [Xen-devel] [v7][PATCH 07/16] hvmloader/e820: construct guest e820 table

2015-07-14 Thread Jan Beulich
 On 14.07.15 at 07:22, tiejun.c...@intel.com wrote:
 +for ( i = 0; i  memory_map.nr_map; i++ )
 +{
 +uint64_t end = e820[i].addr + e820[i].size;

 Either loop index/boundary or used array are wrong here: In the
 earlier loop you copied memory_map[0...nr_map-1] to
 e820[n...n+nr_map-1], but here you're looping looking at
 e820[0...nr_map-1]
 
 You're right. I should lookup all e820[] like this,
 
 for ( i = 0; i  nr; i++ )

Hmm, I would have thought you only care about either part of
the just glued together map.

 +if ( e820[i].type == E820_RAM 
 + low_mem_end  e820[i].addr  low_mem_end  end )

 Assuming you mean to look at the RDM e820[] entries here, this
 is not a correct check: You don't care about partly or fully
 contained, all you care about is whether low_mem_end extends
 beyond the start of the region.
 
 Here I'm looking at the e820 entry indicating low memory. Because
 
 low_mem_end = hvm_info-low_mem_pgend  PAGE_SHIFT;
 
 and when we allocate MMIO in pci.c, its possible to populate RAM so 
 hvm_info-low_mem_pgend would be changed over there. So we need to 
 compensate this loss with high memory. Here memory_map[] also records 
 the original low/high memory, so if low_mem_end is less-than the 
 original we need this compensation.

And I'm not disputing your intentions - I'm merely pointing out that
afaics the code above doesn't match these intentions. In particular
(as said) I don't see why you need to check low_mem_end  end.

Jan


___
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel


Re: [Xen-devel] [v7][PATCH 07/16] hvmloader/e820: construct guest e820 table

2015-07-14 Thread Jan Beulich
 On 14.07.15 at 12:22, tiejun.c...@intel.com wrote:
 On 2015/7/14 17:32, Jan Beulich wrote:
 On 14.07.15 at 07:22, tiejun.c...@intel.com wrote:
 +for ( i = 0; i  memory_map.nr_map; i++ )
 +{
 +uint64_t end = e820[i].addr + e820[i].size;

 Either loop index/boundary or used array are wrong here: In the
 earlier loop you copied memory_map[0...nr_map-1] to
 e820[n...n+nr_map-1], but here you're looping looking at
 e820[0...nr_map-1]

 You're right. I should lookup all e820[] like this,

 for ( i = 0; i  nr; i++ )

 Hmm, I would have thought you only care about either part of
 the just glued together map.

 +if ( e820[i].type == E820_RAM 
 + low_mem_end  e820[i].addr  low_mem_end  end )

 Assuming you mean to look at the RDM e820[] entries here, this
 is not a correct check: You don't care about partly or fully
 contained, all you care about is whether low_mem_end extends
 beyond the start of the region.

 Here I'm looking at the e820 entry indicating low memory. Because

 low_mem_end = hvm_info-low_mem_pgend  PAGE_SHIFT;

 and when we allocate MMIO in pci.c, its possible to populate RAM so
 hvm_info-low_mem_pgend would be changed over there. So we need to
 compensate this loss with high memory. Here memory_map[] also records
 the original low/high memory, so if low_mem_end is less-than the
 original we need this compensation.

 And I'm not disputing your intentions - I'm merely pointing out that
 afaics the code above doesn't match these intentions. In particular
 (as said) I don't see why you need to check low_mem_end  end.

 
 Before we probably relocate RAM,
 
 low_mem_end = hvm_info-low_mem_pgend  PAGE_SHIFT
 
 and the e820 entry specific to low memory,
 
 [e820[X].addr, end]
 
 Here, end = e820[X].addr + e820[X].size;
 
 Now low_mem_end = end.
 
 After that, low_mem_end  end. so if
 
 (low_mem_end  e820[X].addr  low_mem_end  end) is true, this means 
 that associated RAM entry is hitting, right? Then we need to revise this 
 entry as [e820[X].addr, low_mem_end], and compensate [end - low_mem_end] 
 to high memory. Anything I'm still wrong here?

Ah, I think I see now what I misunderstood.

Jan


___
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel


Re: [Xen-devel] [v7][PATCH 07/16] hvmloader/e820: construct guest e820 table

2015-07-13 Thread Jan Beulich
 On 09.07.15 at 07:33, tiejun.c...@intel.com wrote:
 Now we can use that memory map to build our final
 e820 table but it may need to reorder all e820
 entries.

it being what? I'm afraid I can't really make sense of the second
half of the sentence...

 --- a/tools/firmware/hvmloader/e820.c
 +++ b/tools/firmware/hvmloader/e820.c
 @@ -108,7 +108,9 @@ int build_e820_table(struct e820entry *e820,
   unsigned int lowmem_reserved_base,
   unsigned int bios_image_base)
  {
 -unsigned int nr = 0;
 +unsigned int nr = 0, i, j;
 +uint64_t add_high_mem = 0;
 +uint64_t low_mem_end = hvm_info-low_mem_pgend  PAGE_SHIFT;

For the last one I don't see why uint64_t; uint32_t should be just fine
and less (binary) code.

 @@ -194,16 +189,73 @@ int build_e820_table(struct e820entry *e820,
  nr++;
  }
  
 -
 -if ( hvm_info-high_mem_pgend )
 +/*
 + * Construct E820 table according to recorded memory map.
 + *
 + * The memory map created by toolstack may include,
 + *
 + * #1. Low memory region
 + *
 + * Low RAM starts at least from 1M to make sure all standard regions
 + * of the PC memory map, like BIOS, VGA memory-mapped I/O and vgabios,
 + * have enough space.
 + *
 + * #2. Reserved regions if they exist
 + *
 + * #3. High memory region if it exists
 + */
 +for ( i = 0; i  memory_map.nr_map; i++ )
  {
 -e820[nr].addr = ((uint64_t)1  32);
 -e820[nr].size =
 -((uint64_t)hvm_info-high_mem_pgend  PAGE_SHIFT) - 
 e820[nr].addr;
 -e820[nr].type = E820_RAM;
 +e820[nr] = memory_map.map[i];
  nr++;
  }
  
 +/* Low RAM goes here. Reserve space for special pages. */
 +BUG_ON(low_mem_end  (2u  20));
 +
 +/*
 + * We may need to adjust real lowmem end since we may
 + * populate RAM to get enough MMIO previously.

populate? Don't you mean relocate?

 + */
 +for ( i = 0; i  memory_map.nr_map; i++ )
 +{
 +uint64_t end = e820[i].addr + e820[i].size;

Either loop index/boundary or used array are wrong here: In the
earlier loop you copied memory_map[0...nr_map-1] to
e820[n...n+nr_map-1], but here you're looping looking at
e820[0...nr_map-1]

 +if ( e820[i].type == E820_RAM 
 + low_mem_end  e820[i].addr  low_mem_end  end )

Assuming you mean to look at the RDM e820[] entries here, this
is not a correct check: You don't care about partly or fully
contained, all you care about is whether low_mem_end extends
beyond the start of the region.

 +{
 +add_high_mem = end - low_mem_end;
 +e820[i].size = low_mem_end - e820[i].addr;
 +}
 +}
 +
 +/*
 + * And then we also need to adjust highmem.
 + */

A single line comment should use the respective comment style.

 +if ( add_high_mem )
 +{
 +for ( i = 0; i  memory_map.nr_map; i++ )
 +{
 +if ( e820[i].type == E820_RAM 
 + e820[i].addr  (1ull  32))
 +e820[i].size += add_high_mem;
 +}
 +}

But looking at the code I think the comment should be extended to
state that we currently expect there to be exactly one such RAM
region.

 +/* Finally we need to reorder all e820 entries. */

reorder? Perhaps sort?

But despite the many comments - the patch looks a lot better now
than earlier versions.

Jan


___
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel


Re: [Xen-devel] [v7][PATCH 07/16] hvmloader/e820: construct guest e820 table

2015-07-13 Thread Chen, Tiejun

Now we can use that memory map to build our final
e820 table but it may need to reorder all e820
entries.


it being what? I'm afraid I can't really make sense of the second
half of the sentence...


I hope the following can work for you,

...
but finally we should sort them into an increasing order since
we shouldn't assume the original order is always good.




--- a/tools/firmware/hvmloader/e820.c
+++ b/tools/firmware/hvmloader/e820.c
@@ -108,7 +108,9 @@ int build_e820_table(struct e820entry *e820,
   unsigned int lowmem_reserved_base,
   unsigned int bios_image_base)


[snip]




+ */
+for ( i = 0; i  memory_map.nr_map; i++ )
+{
+uint64_t end = e820[i].addr + e820[i].size;


Either loop index/boundary or used array are wrong here: In the
earlier loop you copied memory_map[0...nr_map-1] to
e820[n...n+nr_map-1], but here you're looping looking at
e820[0...nr_map-1]


You're right. I should lookup all e820[] like this,

for ( i = 0; i  nr; i++ )




+if ( e820[i].type == E820_RAM 
+ low_mem_end  e820[i].addr  low_mem_end  end )


Assuming you mean to look at the RDM e820[] entries here, this
is not a correct check: You don't care about partly or fully
contained, all you care about is whether low_mem_end extends
beyond the start of the region.


Here I'm looking at the e820 entry indicating low memory. Because

low_mem_end = hvm_info-low_mem_pgend  PAGE_SHIFT;

and when we allocate MMIO in pci.c, its possible to populate RAM so 
hvm_info-low_mem_pgend would be changed over there. So we need to 
compensate this loss with high memory. Here memory_map[] also records 
the original low/high memory, so if low_mem_end is less-than the 
original we need this compensation.


So here we have two steps to address this issue,

#1. Calculate the loss




+{
+add_high_mem = end - low_mem_end;
+e820[i].size = low_mem_end - e820[i].addr;
+}
+}
+
+/*
+ * And then we also need to adjust highmem.
+ */


A single line comment should use the respective comment style.



#2. Compensate the loss


+if ( add_high_mem )
+{
+for ( i = 0; i  memory_map.nr_map; i++ )


s/memory_map.nr_map/nr


+{
+if ( e820[i].type == E820_RAM 
+ e820[i].addr  (1ull  32))
+e820[i].size += add_high_mem;
+}
+}


But looking at the code I think the comment should be extended to
state that we currently expect there to be exactly one such RAM
region.



I can add this at the beginning of #1 loop,

Its possible to relocate RAM to allocate sufficient MMIO previously so
low_mem_pgend would be changed over there. And here memory_map[] records 
the original low/high memory, so if low_mem_end is less than the 
original we need to revise low/high memory range in e820.



Thanks
Tiejun

___
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel


[Xen-devel] [v7][PATCH 07/16] hvmloader/e820: construct guest e820 table

2015-07-08 Thread Tiejun Chen
Now we can use that memory map to build our final
e820 table but it may need to reorder all e820
entries.

CC: Keir Fraser k...@xen.org
CC: Jan Beulich jbeul...@suse.com
CC: Andrew Cooper andrew.coop...@citrix.com
CC: Ian Jackson ian.jack...@eu.citrix.com
CC: Stefano Stabellini stefano.stabell...@eu.citrix.com
CC: Ian Campbell ian.campb...@citrix.com
CC: Wei Liu wei.l...@citrix.com
Signed-off-by: Tiejun Chen tiejun.c...@intel.com
---
v5 ~ v7:

* Nothing is changed.

v4:

* Rename local variable, low_mem_pgend, to low_mem_end.

* Improve some code comments

* Adjust highmem after lowmem is changed.
 
 tools/firmware/hvmloader/e820.c | 80 +
 1 file changed, 66 insertions(+), 14 deletions(-)

diff --git a/tools/firmware/hvmloader/e820.c b/tools/firmware/hvmloader/e820.c
index 3e53c47..aa2569f 100644
--- a/tools/firmware/hvmloader/e820.c
+++ b/tools/firmware/hvmloader/e820.c
@@ -108,7 +108,9 @@ int build_e820_table(struct e820entry *e820,
  unsigned int lowmem_reserved_base,
  unsigned int bios_image_base)
 {
-unsigned int nr = 0;
+unsigned int nr = 0, i, j;
+uint64_t add_high_mem = 0;
+uint64_t low_mem_end = hvm_info-low_mem_pgend  PAGE_SHIFT;
 
 if ( !lowmem_reserved_base )
 lowmem_reserved_base = 0xA;
@@ -152,13 +154,6 @@ int build_e820_table(struct e820entry *e820,
 e820[nr].type = E820_RESERVED;
 nr++;
 
-/* Low RAM goes here. Reserve space for special pages. */
-BUG_ON((hvm_info-low_mem_pgend  PAGE_SHIFT)  (2u  20));
-e820[nr].addr = 0x10;
-e820[nr].size = (hvm_info-low_mem_pgend  PAGE_SHIFT) - e820[nr].addr;
-e820[nr].type = E820_RAM;
-nr++;
-
 /*
  * Explicitly reserve space for special pages.
  * This space starts at RESERVED_MEMBASE an extends to cover various
@@ -194,16 +189,73 @@ int build_e820_table(struct e820entry *e820,
 nr++;
 }
 
-
-if ( hvm_info-high_mem_pgend )
+/*
+ * Construct E820 table according to recorded memory map.
+ *
+ * The memory map created by toolstack may include,
+ *
+ * #1. Low memory region
+ *
+ * Low RAM starts at least from 1M to make sure all standard regions
+ * of the PC memory map, like BIOS, VGA memory-mapped I/O and vgabios,
+ * have enough space.
+ *
+ * #2. Reserved regions if they exist
+ *
+ * #3. High memory region if it exists
+ */
+for ( i = 0; i  memory_map.nr_map; i++ )
 {
-e820[nr].addr = ((uint64_t)1  32);
-e820[nr].size =
-((uint64_t)hvm_info-high_mem_pgend  PAGE_SHIFT) - e820[nr].addr;
-e820[nr].type = E820_RAM;
+e820[nr] = memory_map.map[i];
 nr++;
 }
 
+/* Low RAM goes here. Reserve space for special pages. */
+BUG_ON(low_mem_end  (2u  20));
+
+/*
+ * We may need to adjust real lowmem end since we may
+ * populate RAM to get enough MMIO previously.
+ */
+for ( i = 0; i  memory_map.nr_map; i++ )
+{
+uint64_t end = e820[i].addr + e820[i].size;
+if ( e820[i].type == E820_RAM 
+ low_mem_end  e820[i].addr  low_mem_end  end )
+{
+add_high_mem = end - low_mem_end;
+e820[i].size = low_mem_end - e820[i].addr;
+}
+}
+
+/*
+ * And then we also need to adjust highmem.
+ */
+if ( add_high_mem )
+{
+for ( i = 0; i  memory_map.nr_map; i++ )
+{
+if ( e820[i].type == E820_RAM 
+ e820[i].addr  (1ull  32))
+e820[i].size += add_high_mem;
+}
+}
+
+/* Finally we need to reorder all e820 entries. */
+for ( j = 0; j  nr-1; j++ )
+{
+for ( i = j+1; i  nr; i++ )
+{
+if ( e820[j].addr  e820[i].addr )
+{
+struct e820entry tmp;
+tmp = e820[j];
+e820[j] = e820[i];
+e820[i] = tmp;
+}
+}
+}
+
 return nr;
 }
 
-- 
1.9.1


___
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel