Re: [Mesa-dev] [PATCH] gallium/winsys/kms: Add support for multi-planes (v2)

[Lepton Wu]

Thanks for reviewing, just back from vacation and send out V3 for review.
I split it to 2 patches now and I removed lazy unmap since it's unnecessary.

On Wed, Feb 21, 2018 at 7:42 AM, Emil Velikov  wrote:
> HI Lepton,
>
> It seems that this has fallen through the cracks.
>
> There's one important functionality change which should be split out
> and documented.
> The rest is just style nitpicks.
>
> On 28 December 2017 at 07:35, Lepton Wu  wrote:
>> v2: address comments from Tomasz Figa
>>a) Add more check for plane size.
>>b) Avoid duplicated mapping and leaked mapping.
>>c) Other minor changes.
> Normally I omit saying "other minor changes" since it don't mean anything.
>
>
>> @@ -105,6 +114,42 @@ kms_sw_is_displaytarget_format_supported( struct 
>> sw_winsys *ws,
>> return TRUE;
>>  }
>>
>> +static struct kms_sw_plane *get_plane(struct kms_sw_displaytarget 
>> *kms_sw_dt,
>> +  enum pipe_format format,
>> +  unsigned width, unsigned height,
>> +  unsigned stride, unsigned offset) {
> Opening bracket should be at the start of next line.
>
>> +   struct kms_sw_plane * tmp, * plane = NULL;
> Through the patch: no space between * and variable name - example: s/* 
> tmp/*tmp/
>
> Add empty line between declarations and code.
>
>> +   if (offset + util_format_get_2d_size(format, stride, height) >
>> +   kms_sw_dt->size) {
>> +  DEBUG_PRINT("KMS-DEBUG: plane too big. format: %d stride: %d height: 
>> %d "
>> +  "offset: %d size:%d\n", format, stride, height, offset,
>> +  kms_sw_dt->size);
>> +  return NULL;
>> +   }
>> +   LIST_FOR_EACH_ENTRY(tmp, _sw_dt->planes, link) {
>> +  if (tmp->offset == offset) {
>> + plane = tmp;
>> + break;
>> +  }
>> +   }
>> +   if (plane) {
>> +  assert(plane->width == width);
>> +  assert(plane->height == height);
>> +  assert(plane->stride == stride);
>> +  assert(plane->dt == kms_sw_dt);
> The only way to hit this if there's serious corruption happening. I'd
> just drop it and "return tmp;" in the loop above.
>
>> +   } else {
>> +  plane = CALLOC_STRUCT(kms_sw_plane);
>> +  if (plane == NULL) return NULL;
> The return statement should be on separate line.
>
> Thorough the patch: swap "foo == NULL" with "!foo"
>
>> @@ -138,17 +182,19 @@ kms_sw_displaytarget_create(struct sw_winsys *ws,
>
>> -   *stride = kms_sw_dt->stride;
>> -   return (struct sw_displaytarget *)kms_sw_dt;
>> -
>> +   *stride = create_req.pitch;
>> +   return (struct sw_displaytarget *) plane;
> Swap the cast with an inline wrapper analogous to the kms_sw_plane() one.
>
>
>> @@ -163,13 +209,19 @@ kms_sw_displaytarget_destroy(struct sw_winsys *ws,
>>   struct sw_displaytarget *dt)
>>  {
>> struct kms_sw_winsys *kms_sw = kms_sw_winsys(ws);
>> -   struct kms_sw_displaytarget *kms_sw_dt = kms_sw_displaytarget(dt);
>> +   struct kms_sw_plane *plane = kms_sw_plane(dt);
>> +   struct kms_sw_displaytarget *kms_sw_dt = plane->dt;
>> struct drm_mode_destroy_dumb destroy_req;
>>
>> kms_sw_dt->ref_count --;
>> if (kms_sw_dt->ref_count > 0)
>>return;
>>
>> +   if (kms_sw_dt->ro_mapped)
>> + munmap(kms_sw_dt->ro_mapped, kms_sw_dt->size);
>> +   if (kms_sw_dt->mapped)
>> + munmap(kms_sw_dt->mapped, kms_sw_dt->size);
>> +
> This hunk moves the munmap from dt_unmap to dt_destroy.
> It should be safe, although it is a subtle functionality change that
> should be split out.
> A commit message should explain why it's needed, etc.
>
> Ideally, the ro_mapped introduction will be another patch.
> Alternatively the commit message should mention it.
>
>
>> @@ -198,16 +255,20 @@ kms_sw_displaytarget_map(struct sw_winsys *ws,
>>return NULL;
>>
>> prot = (flags == PIPE_TRANSFER_READ) ? PROT_READ : (PROT_READ | 
>> PROT_WRITE);
>> -   kms_sw_dt->mapped = mmap(0, kms_sw_dt->size, prot, MAP_SHARED,
>> -kms_sw->fd, map_req.offset);
>> -
>> -   if (kms_sw_dt->mapped == MAP_FAILED)
>> -  return NULL;
>> +   void **ptr = (flags == PIPE_TRANSFER_READ) ? _sw_dt->ro_mapped : 
>> _sw_dt->mapped;
>> +   if (*ptr == NULL) {
> To prevent interment breakage, this NULL check must be part of the
> delayer munmap patch.
>
> HTH
> Emil
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Re: [Mesa-dev] [PATCH] gallium/winsys/kms: Add support for multi-planes (v2)

[Emil Velikov]

HI Lepton,

It seems that this has fallen through the cracks.

There's one important functionality change which should be split out
and documented.
The rest is just style nitpicks.

On 28 December 2017 at 07:35, Lepton Wu  wrote:
> v2: address comments from Tomasz Figa
>a) Add more check for plane size.
>b) Avoid duplicated mapping and leaked mapping.
>c) Other minor changes.
Normally I omit saying "other minor changes" since it don't mean anything.


> @@ -105,6 +114,42 @@ kms_sw_is_displaytarget_format_supported( struct 
> sw_winsys *ws,
> return TRUE;
>  }
>
> +static struct kms_sw_plane *get_plane(struct kms_sw_displaytarget *kms_sw_dt,
> +  enum pipe_format format,
> +  unsigned width, unsigned height,
> +  unsigned stride, unsigned offset) {
Opening bracket should be at the start of next line.

> +   struct kms_sw_plane * tmp, * plane = NULL;
Through the patch: no space between * and variable name - example: s/* tmp/*tmp/

Add empty line between declarations and code.

> +   if (offset + util_format_get_2d_size(format, stride, height) >
> +   kms_sw_dt->size) {
> +  DEBUG_PRINT("KMS-DEBUG: plane too big. format: %d stride: %d height: 
> %d "
> +  "offset: %d size:%d\n", format, stride, height, offset,
> +  kms_sw_dt->size);
> +  return NULL;
> +   }
> +   LIST_FOR_EACH_ENTRY(tmp, _sw_dt->planes, link) {
> +  if (tmp->offset == offset) {
> + plane = tmp;
> + break;
> +  }
> +   }
> +   if (plane) {
> +  assert(plane->width == width);
> +  assert(plane->height == height);
> +  assert(plane->stride == stride);
> +  assert(plane->dt == kms_sw_dt);
The only way to hit this if there's serious corruption happening. I'd
just drop it and "return tmp;" in the loop above.

> +   } else {
> +  plane = CALLOC_STRUCT(kms_sw_plane);
> +  if (plane == NULL) return NULL;
The return statement should be on separate line.

Thorough the patch: swap "foo == NULL" with "!foo"

> @@ -138,17 +182,19 @@ kms_sw_displaytarget_create(struct sw_winsys *ws,

> -   *stride = kms_sw_dt->stride;
> -   return (struct sw_displaytarget *)kms_sw_dt;
> -
> +   *stride = create_req.pitch;
> +   return (struct sw_displaytarget *) plane;
Swap the cast with an inline wrapper analogous to the kms_sw_plane() one.


> @@ -163,13 +209,19 @@ kms_sw_displaytarget_destroy(struct sw_winsys *ws,
>   struct sw_displaytarget *dt)
>  {
> struct kms_sw_winsys *kms_sw = kms_sw_winsys(ws);
> -   struct kms_sw_displaytarget *kms_sw_dt = kms_sw_displaytarget(dt);
> +   struct kms_sw_plane *plane = kms_sw_plane(dt);
> +   struct kms_sw_displaytarget *kms_sw_dt = plane->dt;
> struct drm_mode_destroy_dumb destroy_req;
>
> kms_sw_dt->ref_count --;
> if (kms_sw_dt->ref_count > 0)
>return;
>
> +   if (kms_sw_dt->ro_mapped)
> + munmap(kms_sw_dt->ro_mapped, kms_sw_dt->size);
> +   if (kms_sw_dt->mapped)
> + munmap(kms_sw_dt->mapped, kms_sw_dt->size);
> +
This hunk moves the munmap from dt_unmap to dt_destroy.
It should be safe, although it is a subtle functionality change that
should be split out.
A commit message should explain why it's needed, etc.

Ideally, the ro_mapped introduction will be another patch.
Alternatively the commit message should mention it.


> @@ -198,16 +255,20 @@ kms_sw_displaytarget_map(struct sw_winsys *ws,
>return NULL;
>
> prot = (flags == PIPE_TRANSFER_READ) ? PROT_READ : (PROT_READ | 
> PROT_WRITE);
> -   kms_sw_dt->mapped = mmap(0, kms_sw_dt->size, prot, MAP_SHARED,
> -kms_sw->fd, map_req.offset);
> -
> -   if (kms_sw_dt->mapped == MAP_FAILED)
> -  return NULL;
> +   void **ptr = (flags == PIPE_TRANSFER_READ) ? _sw_dt->ro_mapped : 
> _sw_dt->mapped;
> +   if (*ptr == NULL) {
To prevent interment breakage, this NULL check must be part of the
delayer munmap patch.

HTH
Emil
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Re: [Mesa-dev] [PATCH] gallium/winsys/kms: Add support for multi-planes (v2)

[Tomasz Figa]

On Tue, Jan 9, 2018 at 6:15 PM, Tomasz Figa  wrote:
> Adding some folks on CC for broader distribution.
>
> On Tue, Jan 9, 2018 at 3:52 PM, Lepton Wu  wrote:
>> Gentle ping. Thanks.
>>
>> On Wed, Dec 27, 2017 at 11:35 PM, Lepton Wu  wrote:
>>> v2: address comments from Tomasz Figa
>>>a) Add more check for plane size.
>>>b) Avoid duplicated mapping and leaked mapping.
>>>c) Other minor changes.
>>>
>>> Signed-off-by: Lepton Wu 
>>>
>>> Change-Id: I0863f522976cc8863d6e95492d9346df35c066ec
>>> ---
>>>  src/gallium/winsys/sw/kms-dri/kms_dri_sw_winsys.c | 179 
>>> +++---
>>>  1 file changed, 126 insertions(+), 53 deletions(-)

Well, if it's worth anything:

Reviewed-by: Tomasz Figa 

Would appreciate if some other user of kms_swrast took a look as well. :)

Best regards,
Tomasz
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Re: [Mesa-dev] [PATCH] gallium/winsys/kms: Add support for multi-planes (v2)

[Tomasz Figa]

Adding some folks on CC for broader distribution.

On Tue, Jan 9, 2018 at 3:52 PM, Lepton Wu  wrote:
> Gentle ping. Thanks.
>
> On Wed, Dec 27, 2017 at 11:35 PM, Lepton Wu  wrote:
>> v2: address comments from Tomasz Figa
>>a) Add more check for plane size.
>>b) Avoid duplicated mapping and leaked mapping.
>>c) Other minor changes.
>>
>> Signed-off-by: Lepton Wu 
>>
>> Change-Id: I0863f522976cc8863d6e95492d9346df35c066ec
>> ---
>>  src/gallium/winsys/sw/kms-dri/kms_dri_sw_winsys.c | 179 
>> +++---
>>  1 file changed, 126 insertions(+), 53 deletions(-)
>>
>> diff --git a/src/gallium/winsys/sw/kms-dri/kms_dri_sw_winsys.c 
>> b/src/gallium/winsys/sw/kms-dri/kms_dri_sw_winsys.c
>> index 22e1c936ac5..69c05197081 100644
>> --- a/src/gallium/winsys/sw/kms-dri/kms_dri_sw_winsys.c
>> +++ b/src/gallium/winsys/sw/kms-dri/kms_dri_sw_winsys.c
>> @@ -59,20 +59,29 @@
>>  #define DEBUG_PRINT(msg, ...)
>>  #endif
>>
>> +struct kms_sw_displaytarget;
>>
>> -struct kms_sw_displaytarget
>> -{
>> -   enum pipe_format format;
>> +struct kms_sw_plane {
>> unsigned width;
>> unsigned height;
>> unsigned stride;
>> +   unsigned offset;
>> +   struct kms_sw_displaytarget* dt;
>> +   struct list_head link;
>> +};
>> +
>> +struct kms_sw_displaytarget
>> +{
>> +   enum pipe_format format;
>> unsigned size;
>>
>> uint32_t handle;
>> void *mapped;
>> +   void *ro_mapped;
>>
>> int ref_count;
>> struct list_head link;
>> +   struct list_head planes;
>>  };
>>
>>  struct kms_sw_winsys
>> @@ -83,10 +92,10 @@ struct kms_sw_winsys
>> struct list_head bo_list;
>>  };
>>
>> -static inline struct kms_sw_displaytarget *
>> -kms_sw_displaytarget( struct sw_displaytarget *dt )
>> +static inline struct kms_sw_plane *
>> +kms_sw_plane( struct sw_displaytarget *dt )
>>  {
>> -   return (struct kms_sw_displaytarget *)dt;
>> +   return (struct kms_sw_plane *)dt;
>>  }
>>
>>  static inline struct kms_sw_winsys *
>> @@ -105,6 +114,42 @@ kms_sw_is_displaytarget_format_supported( struct 
>> sw_winsys *ws,
>> return TRUE;
>>  }
>>
>> +static struct kms_sw_plane *get_plane(struct kms_sw_displaytarget 
>> *kms_sw_dt,
>> +  enum pipe_format format,
>> +  unsigned width, unsigned height,
>> +  unsigned stride, unsigned offset) {
>> +   struct kms_sw_plane * tmp, * plane = NULL;
>> +   if (offset + util_format_get_2d_size(format, stride, height) >
>> +   kms_sw_dt->size) {
>> +  DEBUG_PRINT("KMS-DEBUG: plane too big. format: %d stride: %d height: 
>> %d "
>> +  "offset: %d size:%d\n", format, stride, height, offset,
>> +  kms_sw_dt->size);
>> +  return NULL;
>> +   }
>> +   LIST_FOR_EACH_ENTRY(tmp, _sw_dt->planes, link) {
>> +  if (tmp->offset == offset) {
>> + plane = tmp;
>> + break;
>> +  }
>> +   }
>> +   if (plane) {
>> +  assert(plane->width == width);
>> +  assert(plane->height == height);
>> +  assert(plane->stride == stride);
>> +  assert(plane->dt == kms_sw_dt);
>> +   } else {
>> +  plane = CALLOC_STRUCT(kms_sw_plane);
>> +  if (plane == NULL) return NULL;
>> +  plane->width = width;
>> +  plane->height = height;
>> +  plane->stride = stride;
>> +  plane->offset = offset;
>> +  plane->dt = kms_sw_dt;
>> +  list_add(>link, _sw_dt->planes);
>> +   }
>> +   return plane;
>> +}
>> +
>>  static struct sw_displaytarget *
>>  kms_sw_displaytarget_create(struct sw_winsys *ws,
>>  unsigned tex_usage,
>> @@ -124,11 +169,10 @@ kms_sw_displaytarget_create(struct sw_winsys *ws,
>> if (!kms_sw_dt)
>>goto no_dt;
>>
>> +   list_inithead(_sw_dt->planes);
>> kms_sw_dt->ref_count = 1;
>>
>> kms_sw_dt->format = format;
>> -   kms_sw_dt->width = width;
>> -   kms_sw_dt->height = height;
>>
>> memset(_req, 0, sizeof(create_req));
>> create_req.bpp = 32;
>> @@ -138,17 +182,19 @@ kms_sw_displaytarget_create(struct sw_winsys *ws,
>> if (ret)
>>goto free_bo;
>>
>> -   kms_sw_dt->stride = create_req.pitch;
>> kms_sw_dt->size = create_req.size;
>> kms_sw_dt->handle = create_req.handle;
>> +   struct kms_sw_plane* plane = get_plane(kms_sw_dt, format, width, height,
>> +  create_req.pitch, 0);
>> +   if (plane == NULL)
>> +  goto free_bo;
>>
>> list_add(_sw_dt->link, _sw->bo_list);
>>
>> DEBUG_PRINT("KMS-DEBUG: created buffer %u (size %u)\n", 
>> kms_sw_dt->handle, kms_sw_dt->size);
>>
>> -   *stride = kms_sw_dt->stride;
>> -   return (struct sw_displaytarget *)kms_sw_dt;
>> -
>> +   *stride = create_req.pitch;
>> +   return (struct sw_displaytarget *) plane;
>>   free_bo:
>> memset(_req, 0, sizeof destroy_req);
>> destroy_req.handle = create_req.handle;
>> @@ -163,13 +209,19 @@ 

Re: [Mesa-dev] [PATCH] gallium/winsys/kms: Add support for multi-planes (v2)

[Lepton Wu]

Gentle ping. Thanks.

On Wed, Dec 27, 2017 at 11:35 PM, Lepton Wu  wrote:
> v2: address comments from Tomasz Figa
>a) Add more check for plane size.
>b) Avoid duplicated mapping and leaked mapping.
>c) Other minor changes.
>
> Signed-off-by: Lepton Wu 
>
> Change-Id: I0863f522976cc8863d6e95492d9346df35c066ec
> ---
>  src/gallium/winsys/sw/kms-dri/kms_dri_sw_winsys.c | 179 
> +++---
>  1 file changed, 126 insertions(+), 53 deletions(-)
>
> diff --git a/src/gallium/winsys/sw/kms-dri/kms_dri_sw_winsys.c 
> b/src/gallium/winsys/sw/kms-dri/kms_dri_sw_winsys.c
> index 22e1c936ac5..69c05197081 100644
> --- a/src/gallium/winsys/sw/kms-dri/kms_dri_sw_winsys.c
> +++ b/src/gallium/winsys/sw/kms-dri/kms_dri_sw_winsys.c
> @@ -59,20 +59,29 @@
>  #define DEBUG_PRINT(msg, ...)
>  #endif
>
> +struct kms_sw_displaytarget;
>
> -struct kms_sw_displaytarget
> -{
> -   enum pipe_format format;
> +struct kms_sw_plane {
> unsigned width;
> unsigned height;
> unsigned stride;
> +   unsigned offset;
> +   struct kms_sw_displaytarget* dt;
> +   struct list_head link;
> +};
> +
> +struct kms_sw_displaytarget
> +{
> +   enum pipe_format format;
> unsigned size;
>
> uint32_t handle;
> void *mapped;
> +   void *ro_mapped;
>
> int ref_count;
> struct list_head link;
> +   struct list_head planes;
>  };
>
>  struct kms_sw_winsys
> @@ -83,10 +92,10 @@ struct kms_sw_winsys
> struct list_head bo_list;
>  };
>
> -static inline struct kms_sw_displaytarget *
> -kms_sw_displaytarget( struct sw_displaytarget *dt )
> +static inline struct kms_sw_plane *
> +kms_sw_plane( struct sw_displaytarget *dt )
>  {
> -   return (struct kms_sw_displaytarget *)dt;
> +   return (struct kms_sw_plane *)dt;
>  }
>
>  static inline struct kms_sw_winsys *
> @@ -105,6 +114,42 @@ kms_sw_is_displaytarget_format_supported( struct 
> sw_winsys *ws,
> return TRUE;
>  }
>
> +static struct kms_sw_plane *get_plane(struct kms_sw_displaytarget *kms_sw_dt,
> +  enum pipe_format format,
> +  unsigned width, unsigned height,
> +  unsigned stride, unsigned offset) {
> +   struct kms_sw_plane * tmp, * plane = NULL;
> +   if (offset + util_format_get_2d_size(format, stride, height) >
> +   kms_sw_dt->size) {
> +  DEBUG_PRINT("KMS-DEBUG: plane too big. format: %d stride: %d height: 
> %d "
> +  "offset: %d size:%d\n", format, stride, height, offset,
> +  kms_sw_dt->size);
> +  return NULL;
> +   }
> +   LIST_FOR_EACH_ENTRY(tmp, _sw_dt->planes, link) {
> +  if (tmp->offset == offset) {
> + plane = tmp;
> + break;
> +  }
> +   }
> +   if (plane) {
> +  assert(plane->width == width);
> +  assert(plane->height == height);
> +  assert(plane->stride == stride);
> +  assert(plane->dt == kms_sw_dt);
> +   } else {
> +  plane = CALLOC_STRUCT(kms_sw_plane);
> +  if (plane == NULL) return NULL;
> +  plane->width = width;
> +  plane->height = height;
> +  plane->stride = stride;
> +  plane->offset = offset;
> +  plane->dt = kms_sw_dt;
> +  list_add(>link, _sw_dt->planes);
> +   }
> +   return plane;
> +}
> +
>  static struct sw_displaytarget *
>  kms_sw_displaytarget_create(struct sw_winsys *ws,
>  unsigned tex_usage,
> @@ -124,11 +169,10 @@ kms_sw_displaytarget_create(struct sw_winsys *ws,
> if (!kms_sw_dt)
>goto no_dt;
>
> +   list_inithead(_sw_dt->planes);
> kms_sw_dt->ref_count = 1;
>
> kms_sw_dt->format = format;
> -   kms_sw_dt->width = width;
> -   kms_sw_dt->height = height;
>
> memset(_req, 0, sizeof(create_req));
> create_req.bpp = 32;
> @@ -138,17 +182,19 @@ kms_sw_displaytarget_create(struct sw_winsys *ws,
> if (ret)
>goto free_bo;
>
> -   kms_sw_dt->stride = create_req.pitch;
> kms_sw_dt->size = create_req.size;
> kms_sw_dt->handle = create_req.handle;
> +   struct kms_sw_plane* plane = get_plane(kms_sw_dt, format, width, height,
> +  create_req.pitch, 0);
> +   if (plane == NULL)
> +  goto free_bo;
>
> list_add(_sw_dt->link, _sw->bo_list);
>
> DEBUG_PRINT("KMS-DEBUG: created buffer %u (size %u)\n", 
> kms_sw_dt->handle, kms_sw_dt->size);
>
> -   *stride = kms_sw_dt->stride;
> -   return (struct sw_displaytarget *)kms_sw_dt;
> -
> +   *stride = create_req.pitch;
> +   return (struct sw_displaytarget *) plane;
>   free_bo:
> memset(_req, 0, sizeof destroy_req);
> destroy_req.handle = create_req.handle;
> @@ -163,13 +209,19 @@ kms_sw_displaytarget_destroy(struct sw_winsys *ws,
>   struct sw_displaytarget *dt)
>  {
> struct kms_sw_winsys *kms_sw = kms_sw_winsys(ws);
> -   struct kms_sw_displaytarget *kms_sw_dt = kms_sw_displaytarget(dt);
> +   struct kms_sw_plane *plane = kms_sw_plane(dt);
> 

[Mesa-dev] [PATCH] gallium/winsys/kms: Add support for multi-planes (v2)

[Lepton Wu]

v2: address comments from Tomasz Figa
   a) Add more check for plane size.
   b) Avoid duplicated mapping and leaked mapping.
   c) Other minor changes.

Signed-off-by: Lepton Wu 

Change-Id: I0863f522976cc8863d6e95492d9346df35c066ec
---
 src/gallium/winsys/sw/kms-dri/kms_dri_sw_winsys.c | 179 +++---
 1 file changed, 126 insertions(+), 53 deletions(-)

diff --git a/src/gallium/winsys/sw/kms-dri/kms_dri_sw_winsys.c 
b/src/gallium/winsys/sw/kms-dri/kms_dri_sw_winsys.c
index 22e1c936ac5..69c05197081 100644
--- a/src/gallium/winsys/sw/kms-dri/kms_dri_sw_winsys.c
+++ b/src/gallium/winsys/sw/kms-dri/kms_dri_sw_winsys.c
@@ -59,20 +59,29 @@
 #define DEBUG_PRINT(msg, ...)
 #endif
 
+struct kms_sw_displaytarget;
 
-struct kms_sw_displaytarget
-{
-   enum pipe_format format;
+struct kms_sw_plane {
unsigned width;
unsigned height;
unsigned stride;
+   unsigned offset;
+   struct kms_sw_displaytarget* dt;
+   struct list_head link;
+};
+
+struct kms_sw_displaytarget
+{
+   enum pipe_format format;
unsigned size;
 
uint32_t handle;
void *mapped;
+   void *ro_mapped;
 
int ref_count;
struct list_head link;
+   struct list_head planes;
 };
 
 struct kms_sw_winsys
@@ -83,10 +92,10 @@ struct kms_sw_winsys
struct list_head bo_list;
 };
 
-static inline struct kms_sw_displaytarget *
-kms_sw_displaytarget( struct sw_displaytarget *dt )
+static inline struct kms_sw_plane *
+kms_sw_plane( struct sw_displaytarget *dt )
 {
-   return (struct kms_sw_displaytarget *)dt;
+   return (struct kms_sw_plane *)dt;
 }
 
 static inline struct kms_sw_winsys *
@@ -105,6 +114,42 @@ kms_sw_is_displaytarget_format_supported( struct sw_winsys 
*ws,
return TRUE;
 }
 
+static struct kms_sw_plane *get_plane(struct kms_sw_displaytarget *kms_sw_dt,
+  enum pipe_format format,
+  unsigned width, unsigned height,
+  unsigned stride, unsigned offset) {
+   struct kms_sw_plane * tmp, * plane = NULL;
+   if (offset + util_format_get_2d_size(format, stride, height) >
+   kms_sw_dt->size) {
+  DEBUG_PRINT("KMS-DEBUG: plane too big. format: %d stride: %d height: %d "
+  "offset: %d size:%d\n", format, stride, height, offset,
+  kms_sw_dt->size);
+  return NULL;
+   }
+   LIST_FOR_EACH_ENTRY(tmp, _sw_dt->planes, link) {
+  if (tmp->offset == offset) {
+ plane = tmp;
+ break;
+  }
+   }
+   if (plane) {
+  assert(plane->width == width);
+  assert(plane->height == height);
+  assert(plane->stride == stride);
+  assert(plane->dt == kms_sw_dt);
+   } else {
+  plane = CALLOC_STRUCT(kms_sw_plane);
+  if (plane == NULL) return NULL;
+  plane->width = width;
+  plane->height = height;
+  plane->stride = stride;
+  plane->offset = offset;
+  plane->dt = kms_sw_dt;
+  list_add(>link, _sw_dt->planes);
+   }
+   return plane;
+}
+
 static struct sw_displaytarget *
 kms_sw_displaytarget_create(struct sw_winsys *ws,
 unsigned tex_usage,
@@ -124,11 +169,10 @@ kms_sw_displaytarget_create(struct sw_winsys *ws,
if (!kms_sw_dt)
   goto no_dt;
 
+   list_inithead(_sw_dt->planes);
kms_sw_dt->ref_count = 1;
 
kms_sw_dt->format = format;
-   kms_sw_dt->width = width;
-   kms_sw_dt->height = height;
 
memset(_req, 0, sizeof(create_req));
create_req.bpp = 32;
@@ -138,17 +182,19 @@ kms_sw_displaytarget_create(struct sw_winsys *ws,
if (ret)
   goto free_bo;
 
-   kms_sw_dt->stride = create_req.pitch;
kms_sw_dt->size = create_req.size;
kms_sw_dt->handle = create_req.handle;
+   struct kms_sw_plane* plane = get_plane(kms_sw_dt, format, width, height,
+  create_req.pitch, 0);
+   if (plane == NULL)
+  goto free_bo;
 
list_add(_sw_dt->link, _sw->bo_list);
 
DEBUG_PRINT("KMS-DEBUG: created buffer %u (size %u)\n", kms_sw_dt->handle, 
kms_sw_dt->size);
 
-   *stride = kms_sw_dt->stride;
-   return (struct sw_displaytarget *)kms_sw_dt;
-
+   *stride = create_req.pitch;
+   return (struct sw_displaytarget *) plane;
  free_bo:
memset(_req, 0, sizeof destroy_req);
destroy_req.handle = create_req.handle;
@@ -163,13 +209,19 @@ kms_sw_displaytarget_destroy(struct sw_winsys *ws,
  struct sw_displaytarget *dt)
 {
struct kms_sw_winsys *kms_sw = kms_sw_winsys(ws);
-   struct kms_sw_displaytarget *kms_sw_dt = kms_sw_displaytarget(dt);
+   struct kms_sw_plane *plane = kms_sw_plane(dt);
+   struct kms_sw_displaytarget *kms_sw_dt = plane->dt;
struct drm_mode_destroy_dumb destroy_req;
 
kms_sw_dt->ref_count --;
if (kms_sw_dt->ref_count > 0)
   return;
 
+   if (kms_sw_dt->ro_mapped)
+ munmap(kms_sw_dt->ro_mapped, kms_sw_dt->size);
+   if (kms_sw_dt->mapped)
+ munmap(kms_sw_dt->mapped, kms_sw_dt->size);
+
memset(_req, 0, sizeof