aboutsummaryrefslogblamecommitdiffstats
path: root/drivers/gpu/drm/i915/i915_gem.c
blob: 6b4a2bd20640598f1e5407dc095ef3a9bed0d6b7 (plain) (tree)
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163



















































                                                                               


                                                    

























                                                                      





















                                                                         





































































                                                                             
                           




















                                                                            

                                                  
   





                                                  
 
                           
                                
 





























                                                                                 
                 

 





                                                                       
                                                        
                       
                                 
                               

                                     
























                                                                            


                                                            
                   

















                                                                              
                                          

                 


                                         
         







                                         
          















































































































































































































































































































                                                                                
                                                 









                                                                     
               








































































































































                                                                              

                                                    







                                                                     
          

































































































































































































































































































































































































































                                                                                         

                                                                    
































































































































































































































































                                                                               


                                                  





























































                                                                                 
                                                        



                                                                   
                                 















                                                                       

                                                 







































































































                                                                                


                                                                               
                                                               
                                                                                     







                                                                        
                                                    














                                                                            















































































































                                                                                



                                                                           















































































































































































































































































































































































                                                                               

                                             

















































































                                                                            



                                                                        
                         
         





                                                                               





                                                                           
















































                                                                         

                                                 
                           
         




                                                         



                                         






















                                                                          
                                                    







                                                         
 

                                                                





                                                                         

                                                       
                                              











                                                                     
                 



























                                                                          
                                                      










                                                                   
                                 
                                 


                                                     



















                                                                      




                                                         












                                                                      





















                                                            





                                                                           

                                                                         
                                                





















                                                                     



                                                                                    






                                                         


                             






                                                          
                                                        

                
                                 

                               
                                                  
                   





                                          
 


                                                                
















                                                        
/*
 * Copyright © 2008 Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 *
 * Authors:
 *    Eric Anholt <eric@anholt.net>
 *
 */

#include "drmP.h"
#include "drm.h"
#include "i915_drm.h"
#include "i915_drv.h"
#include <linux/swap.h>

static int
i915_gem_object_set_domain(struct drm_gem_object *obj,
			    uint32_t read_domains,
			    uint32_t write_domain);
static int
i915_gem_object_set_domain_range(struct drm_gem_object *obj,
				 uint64_t offset,
				 uint64_t size,
				 uint32_t read_domains,
				 uint32_t write_domain);
static int
i915_gem_set_domain(struct drm_gem_object *obj,
		    struct drm_file *file_priv,
		    uint32_t read_domains,
		    uint32_t write_domain);
static int i915_gem_object_get_page_list(struct drm_gem_object *obj);
static void i915_gem_object_free_page_list(struct drm_gem_object *obj);
static int i915_gem_object_wait_rendering(struct drm_gem_object *obj);

static void
i915_gem_cleanup_ringbuffer(struct drm_device *dev);

int
i915_gem_init_ioctl(struct drm_device *dev, void *data,
		    struct drm_file *file_priv)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	struct drm_i915_gem_init *args = data;

	mutex_lock(&dev->struct_mutex);

	if (args->gtt_start >= args->gtt_end ||
	    (args->gtt_start & (PAGE_SIZE - 1)) != 0 ||
	    (args->gtt_end & (PAGE_SIZE - 1)) != 0) {
		mutex_unlock(&dev->struct_mutex);
		return -EINVAL;
	}

	drm_mm_init(&dev_priv->mm.gtt_space, args->gtt_start,
	    args->gtt_end - args->gtt_start);

	dev->gtt_total = (uint32_t) (args->gtt_end - args->gtt_start);

	mutex_unlock(&dev->struct_mutex);

	return 0;
}

int
i915_gem_get_aperture_ioctl(struct drm_device *dev, void *data,
			    struct drm_file *file_priv)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	struct drm_i915_gem_get_aperture *args = data;
	struct drm_i915_gem_object *obj_priv;

	if (!(dev->driver->driver_features & DRIVER_GEM))
		return -ENODEV;

	args->aper_size = dev->gtt_total;
	args->aper_available_size = args->aper_size;

	list_for_each_entry(obj_priv, &dev_priv->mm.active_list, list) {
		if (obj_priv->pin_count > 0)
			args->aper_available_size -= obj_priv->obj->size;
	}

	return 0;
}


/**
 * Creates a new mm object and returns a handle to it.
 */
int
i915_gem_create_ioctl(struct drm_device *dev, void *data,
		      struct drm_file *file_priv)
{
	struct drm_i915_gem_create *args = data;
	struct drm_gem_object *obj;
	int handle, ret;

	args->size = roundup(args->size, PAGE_SIZE);

	/* Allocate the new object */
	obj = drm_gem_object_alloc(dev, args->size);
	if (obj == NULL)
		return -ENOMEM;

	ret = drm_gem_handle_create(file_priv, obj, &handle);
	mutex_lock(&dev->struct_mutex);
	drm_gem_object_handle_unreference(obj);
	mutex_unlock(&dev->struct_mutex);

	if (ret)
		return ret;

	args->handle = handle;

	return 0;
}

/**
 * Reads data from the object referenced by handle.
 *
 * On error, the contents of *data are undefined.
 */
int
i915_gem_pread_ioctl(struct drm_device *dev, void *data,
		     struct drm_file *file_priv)
{
	struct drm_i915_gem_pread *args = data;
	struct drm_gem_object *obj;
	struct drm_i915_gem_object *obj_priv;
	ssize_t read;
	loff_t offset;
	int ret;

	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
	if (obj == NULL)
		return -EBADF;
	obj_priv = obj->driver_private;

	/* Bounds check source.
	 *
	 * XXX: This could use review for overflow issues...
	 */
	if (args->offset > obj->size || args->size > obj->size ||
	    args->offset + args->size > obj->size) {
		drm_gem_object_unreference(obj);
		return -EINVAL;
	}

	mutex_lock(&dev->struct_mutex);

	ret = i915_gem_object_set_domain_range(obj, args->offset, args->size,
					       I915_GEM_DOMAIN_CPU, 0);
	if (ret != 0) {
		drm_gem_object_unreference(obj);
		mutex_unlock(&dev->struct_mutex);
		return ret;
	}

	offset = args->offset;

	read = vfs_read(obj->filp, (char __user *)(uintptr_t)args->data_ptr,
			args->size, &offset);
	if (read != args->size) {
		drm_gem_object_unreference(obj);
		mutex_unlock(&dev->struct_mutex);
		if (read < 0)
			return read;
		else
			return -EINVAL;
	}

	drm_gem_object_unreference(obj);
	mutex_unlock(&dev->struct_mutex);

	return 0;
}

/* This is the fast write path which cannot handle
 * page faults in the source data
 */

static inline int
fast_user_write(struct io_mapping *mapping,
		loff_t page_base, int page_offset,
		char __user *user_data,
		int length)
{
	char *vaddr_atomic;
	unsigned long unwritten;

	vaddr_atomic = io_mapping_map_atomic_wc(mapping, page_base);
	unwritten = __copy_from_user_inatomic_nocache(vaddr_atomic + page_offset,
						      user_data, length);
	io_mapping_unmap_atomic(vaddr_atomic);
	if (unwritten)
		return -EFAULT;
	return 0;
}

/* Here's the write path which can sleep for
 * page faults
 */

static inline int
slow_user_write(struct io_mapping *mapping,
		loff_t page_base, int page_offset,
		char __user *user_data,
		int length)
{
	char __iomem *vaddr;
	unsigned long unwritten;

	vaddr = io_mapping_map_wc(mapping, page_base);
	if (vaddr == NULL)
		return -EFAULT;
	unwritten = __copy_from_user(vaddr + page_offset,
				     user_data, length);
	io_mapping_unmap(vaddr);
	if (unwritten)
		return -EFAULT;
	return 0;
}

static int
i915_gem_gtt_pwrite(struct drm_device *dev, struct drm_gem_object *obj,
		    struct drm_i915_gem_pwrite *args,
		    struct drm_file *file_priv)
{
	struct drm_i915_gem_object *obj_priv = obj->driver_private;
	drm_i915_private_t *dev_priv = dev->dev_private;
	ssize_t remain;
	loff_t offset, page_base;
	char __user *user_data;
	int page_offset, page_length;
	int ret;

	user_data = (char __user *) (uintptr_t) args->data_ptr;
	remain = args->size;
	if (!access_ok(VERIFY_READ, user_data, remain))
		return -EFAULT;


	mutex_lock(&dev->struct_mutex);
	ret = i915_gem_object_pin(obj, 0);
	if (ret) {
		mutex_unlock(&dev->struct_mutex);
		return ret;
	}
	ret = i915_gem_set_domain(obj, file_priv,
				  I915_GEM_DOMAIN_GTT, I915_GEM_DOMAIN_GTT);
	if (ret)
		goto fail;

	obj_priv = obj->driver_private;
	offset = obj_priv->gtt_offset + args->offset;
	obj_priv->dirty = 1;

	while (remain > 0) {
		/* Operation in this page
		 *
		 * page_base = page offset within aperture
		 * page_offset = offset within page
		 * page_length = bytes to copy for this page
		 */
		page_base = (offset & ~(PAGE_SIZE-1));
		page_offset = offset & (PAGE_SIZE-1);
		page_length = remain;
		if ((page_offset + remain) > PAGE_SIZE)
			page_length = PAGE_SIZE - page_offset;

		ret = fast_user_write (dev_priv->mm.gtt_mapping, page_base,
				       page_offset, user_data, page_length);

		/* If we get a fault while copying data, then (presumably) our
		 * source page isn't available. In this case, use the
		 * non-atomic function
		 */
		if (ret) {
			ret = slow_user_write (dev_priv->mm.gtt_mapping,
					       page_base, page_offset,
					       user_data, page_length);
			if (ret)
				goto fail;
		}

		remain -= page_length;
		user_data += page_length;
		offset += page_length;
	}

fail:
	i915_gem_object_unpin(obj);
	mutex_unlock(&dev->struct_mutex);

	return ret;
}

static int
i915_gem_shmem_pwrite(struct drm_device *dev, struct drm_gem_object *obj,
		      struct drm_i915_gem_pwrite *args,
		      struct drm_file *file_priv)
{
	int ret;
	loff_t offset;
	ssize_t written;

	mutex_lock(&dev->struct_mutex);

	ret = i915_gem_set_domain(obj, file_priv,
				  I915_GEM_DOMAIN_CPU, I915_GEM_DOMAIN_CPU);
	if (ret) {
		mutex_unlock(&dev->struct_mutex);
		return ret;
	}

	offset = args->offset;

	written = vfs_write(obj->filp,
			    (char __user *)(uintptr_t) args->data_ptr,
			    args->size, &offset);
	if (written != args->size) {
		mutex_unlock(&dev->struct_mutex);
		if (written < 0)
			return written;
		else
			return -EINVAL;
	}

	mutex_unlock(&dev->struct_mutex);

	return 0;
}

/**
 * Writes data to the object referenced by handle.
 *
 * On error, the contents of the buffer that were to be modified are undefined.
 */
int
i915_gem_pwrite_ioctl(struct drm_device *dev, void *data,
		      struct drm_file *file_priv)
{
	struct drm_i915_gem_pwrite *args = data;
	struct drm_gem_object *obj;
	struct drm_i915_gem_object *obj_priv;
	int ret = 0;

	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
	if (obj == NULL)
		return -EBADF;
	obj_priv = obj->driver_private;

	/* Bounds check destination.
	 *
	 * XXX: This could use review for overflow issues...
	 */
	if (args->offset > obj->size || args->size > obj->size ||
	    args->offset + args->size > obj->size) {
		drm_gem_object_unreference(obj);
		return -EINVAL;
	}

	/* We can only do the GTT pwrite on untiled buffers, as otherwise
	 * it would end up going through the fenced access, and we'll get
	 * different detiling behavior between reading and writing.
	 * pread/pwrite currently are reading and writing from the CPU
	 * perspective, requiring manual detiling by the client.
	 */
	if (obj_priv->tiling_mode == I915_TILING_NONE &&
	    dev->gtt_total != 0)
		ret = i915_gem_gtt_pwrite(dev, obj, args, file_priv);
	else
		ret = i915_gem_shmem_pwrite(dev, obj, args, file_priv);

#if WATCH_PWRITE
	if (ret)
		DRM_INFO("pwrite failed %d\n", ret);
#endif

	drm_gem_object_unreference(obj);

	return ret;
}

/**
 * Called when user space prepares to use an object
 */
int
i915_gem_set_domain_ioctl(struct drm_device *dev, void *data,
			  struct drm_file *file_priv)
{
	struct drm_i915_gem_set_domain *args = data;
	struct drm_gem_object *obj;
	int ret;

	if (!(dev->driver->driver_features & DRIVER_GEM))
		return -ENODEV;

	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
	if (obj == NULL)
		return -EBADF;

	mutex_lock(&dev->struct_mutex);
#if WATCH_BUF
	DRM_INFO("set_domain_ioctl %p(%d), %08x %08x\n",
		 obj, obj->size, args->read_domains, args->write_domain);
#endif
	ret = i915_gem_set_domain(obj, file_priv,
				  args->read_domains, args->write_domain);
	drm_gem_object_unreference(obj);
	mutex_unlock(&dev->struct_mutex);
	return ret;
}

/**
 * Called when user space has done writes to this buffer
 */
int
i915_gem_sw_finish_ioctl(struct drm_device *dev, void *data,
		      struct drm_file *file_priv)
{
	struct drm_i915_gem_sw_finish *args = data;
	struct drm_gem_object *obj;
	struct drm_i915_gem_object *obj_priv;
	int ret = 0;

	if (!(dev->driver->driver_features & DRIVER_GEM))
		return -ENODEV;

	mutex_lock(&dev->struct_mutex);
	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
	if (obj == NULL) {
		mutex_unlock(&dev->struct_mutex);
		return -EBADF;
	}

#if WATCH_BUF
	DRM_INFO("%s: sw_finish %d (%p %d)\n",
		 __func__, args->handle, obj, obj->size);
#endif
	obj_priv = obj->driver_private;

	/* Pinned buffers may be scanout, so flush the cache */
	if ((obj->write_domain & I915_GEM_DOMAIN_CPU) && obj_priv->pin_count) {
		i915_gem_clflush_object(obj);
		drm_agp_chipset_flush(dev);
	}
	drm_gem_object_unreference(obj);
	mutex_unlock(&dev->struct_mutex);
	return ret;
}

/**
 * Maps the contents of an object, returning the address it is mapped
 * into.
 *
 * While the mapping holds a reference on the contents of the object, it doesn't
 * imply a ref on the object itself.
 */
int
i915_gem_mmap_ioctl(struct drm_device *dev, void *data,
		   struct drm_file *file_priv)
{
	struct drm_i915_gem_mmap *args = data;
	struct drm_gem_object *obj;
	loff_t offset;
	unsigned long addr;

	if (!(dev->driver->driver_features & DRIVER_GEM))
		return -ENODEV;

	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
	if (obj == NULL)
		return -EBADF;

	offset = args->offset;

	down_write(&current->mm->mmap_sem);
	addr = do_mmap(obj->filp, 0, args->size,
		       PROT_READ | PROT_WRITE, MAP_SHARED,
		       args->offset);
	up_write(&current->mm->mmap_sem);
	mutex_lock(&dev->struct_mutex);
	drm_gem_object_unreference(obj);
	mutex_unlock(&dev->struct_mutex);
	if (IS_ERR((void *)addr))
		return addr;

	args->addr_ptr = (uint64_t) addr;

	return 0;
}

static void
i915_gem_object_free_page_list(struct drm_gem_object *obj)
{
	struct drm_i915_gem_object *obj_priv = obj->driver_private;
	int page_count = obj->size / PAGE_SIZE;
	int i;

	if (obj_priv->page_list == NULL)
		return;


	for (i = 0; i < page_count; i++)
		if (obj_priv->page_list[i] != NULL) {
			if (obj_priv->dirty)
				set_page_dirty(obj_priv->page_list[i]);
			mark_page_accessed(obj_priv->page_list[i]);
			page_cache_release(obj_priv->page_list[i]);
		}
	obj_priv->dirty = 0;

	drm_free(obj_priv->page_list,
		 page_count * sizeof(struct page *),
		 DRM_MEM_DRIVER);
	obj_priv->page_list = NULL;
}

static void
i915_gem_object_move_to_active(struct drm_gem_object *obj)
{
	struct drm_device *dev = obj->dev;
	drm_i915_private_t *dev_priv = dev->dev_private;
	struct drm_i915_gem_object *obj_priv = obj->driver_private;

	/* Add a reference if we're newly entering the active list. */
	if (!obj_priv->active) {
		drm_gem_object_reference(obj);
		obj_priv->active = 1;
	}
	/* Move from whatever list we were on to the tail of execution. */
	list_move_tail(&obj_priv->list,
		       &dev_priv->mm.active_list);
}


static void
i915_gem_object_move_to_inactive(struct drm_gem_object *obj)
{
	struct drm_device *dev = obj->dev;
	drm_i915_private_t *dev_priv = dev->dev_private;
	struct drm_i915_gem_object *obj_priv = obj->driver_private;

	i915_verify_inactive(dev, __FILE__, __LINE__);
	if (obj_priv->pin_count != 0)
		list_del_init(&obj_priv->list);
	else
		list_move_tail(&obj_priv->list, &dev_priv->mm.inactive_list);

	if (obj_priv->active) {
		obj_priv->active = 0;
		drm_gem_object_unreference(obj);
	}
	i915_verify_inactive(dev, __FILE__, __LINE__);
}

/**
 * Creates a new sequence number, emitting a write of it to the status page
 * plus an interrupt, which will trigger i915_user_interrupt_handler.
 *
 * Must be called with struct_lock held.
 *
 * Returned sequence numbers are nonzero on success.
 */
static uint32_t
i915_add_request(struct drm_device *dev, uint32_t flush_domains)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	struct drm_i915_gem_request *request;
	uint32_t seqno;
	int was_empty;
	RING_LOCALS;

	request = drm_calloc(1, sizeof(*request), DRM_MEM_DRIVER);
	if (request == NULL)
		return 0;

	/* Grab the seqno we're going to make this request be, and bump the
	 * next (skipping 0 so it can be the reserved no-seqno value).
	 */
	seqno = dev_priv->mm.next_gem_seqno;
	dev_priv->mm.next_gem_seqno++;
	if (dev_priv->mm.next_gem_seqno == 0)
		dev_priv->mm.next_gem_seqno++;

	BEGIN_LP_RING(4);
	OUT_RING(MI_STORE_DWORD_INDEX);
	OUT_RING(I915_GEM_HWS_INDEX << MI_STORE_DWORD_INDEX_SHIFT);
	OUT_RING(seqno);

	OUT_RING(MI_USER_INTERRUPT);
	ADVANCE_LP_RING();

	DRM_DEBUG("%d\n", seqno);

	request->seqno = seqno;
	request->emitted_jiffies = jiffies;
	request->flush_domains = flush_domains;
	was_empty = list_empty(&dev_priv->mm.request_list);
	list_add_tail(&request->list, &dev_priv->mm.request_list);

	if (was_empty && !dev_priv->mm.suspended)
		schedule_delayed_work(&dev_priv->mm.retire_work, HZ);
	return seqno;
}

/**
 * Command execution barrier
 *
 * Ensures that all commands in the ring are finished
 * before signalling the CPU
 */
static uint32_t
i915_retire_commands(struct drm_device *dev)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	uint32_t cmd = MI_FLUSH | MI_NO_WRITE_FLUSH;
	uint32_t flush_domains = 0;
	RING_LOCALS;

	/* The sampler always gets flushed on i965 (sigh) */
	if (IS_I965G(dev))
		flush_domains |= I915_GEM_DOMAIN_SAMPLER;
	BEGIN_LP_RING(2);
	OUT_RING(cmd);
	OUT_RING(0); /* noop */
	ADVANCE_LP_RING();
	return flush_domains;
}

/**
 * Moves buffers associated only with the given active seqno from the active
 * to inactive list, potentially freeing them.
 */
static void
i915_gem_retire_request(struct drm_device *dev,
			struct drm_i915_gem_request *request)
{
	drm_i915_private_t *dev_priv = dev->dev_private;

	/* Move any buffers on the active list that are no longer referenced
	 * by the ringbuffer to the flushing/inactive lists as appropriate.
	 */
	while (!list_empty(&dev_priv->mm.active_list)) {
		struct drm_gem_object *obj;
		struct drm_i915_gem_object *obj_priv;

		obj_priv = list_first_entry(&dev_priv->mm.active_list,
					    struct drm_i915_gem_object,
					    list);
		obj = obj_priv->obj;

		/* If the seqno being retired doesn't match the oldest in the
		 * list, then the oldest in the list must still be newer than
		 * this seqno.
		 */
		if (obj_priv->last_rendering_seqno != request->seqno)
			return;
#if WATCH_LRU
		DRM_INFO("%s: retire %d moves to inactive list %p\n",
			 __func__, request->seqno, obj);
#endif

		if (obj->write_domain != 0) {
			list_move_tail(&obj_priv->list,
				       &dev_priv->mm.flushing_list);
		} else {
			i915_gem_object_move_to_inactive(obj);
		}
	}

	if (request->flush_domains != 0) {
		struct drm_i915_gem_object *obj_priv, *next;

		/* Clear the write domain and activity from any buffers
		 * that are just waiting for a flush matching the one retired.
		 */
		list_for_each_entry_safe(obj_priv, next,
					 &dev_priv->mm.flushing_list, list) {
			struct drm_gem_object *obj = obj_priv->obj;

			if (obj->write_domain & request->flush_domains) {
				obj->write_domain = 0;
				i915_gem_object_move_to_inactive(obj);
			}
		}

	}
}

/**
 * Returns true if seq1 is later than seq2.
 */
static int
i915_seqno_passed(uint32_t seq1, uint32_t seq2)
{
	return (int32_t)(seq1 - seq2) >= 0;
}

uint32_t
i915_get_gem_seqno(struct drm_device *dev)
{
	drm_i915_private_t *dev_priv = dev->dev_private;

	return READ_HWSP(dev_priv, I915_GEM_HWS_INDEX);
}

/**
 * This function clears the request list as sequence numbers are passed.
 */
void
i915_gem_retire_requests(struct drm_device *dev)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	uint32_t seqno;

	seqno = i915_get_gem_seqno(dev);

	while (!list_empty(&dev_priv->mm.request_list)) {
		struct drm_i915_gem_request *request;
		uint32_t retiring_seqno;

		request = list_first_entry(&dev_priv->mm.request_list,
					   struct drm_i915_gem_request,
					   list);
		retiring_seqno = request->seqno;

		if (i915_seqno_passed(seqno, retiring_seqno) ||
		    dev_priv->mm.wedged) {
			i915_gem_retire_request(dev, request);

			list_del(&request->list);
			drm_free(request, sizeof(*request), DRM_MEM_DRIVER);
		} else
			break;
	}
}

void
i915_gem_retire_work_handler(struct work_struct *work)
{
	drm_i915_private_t *dev_priv;
	struct drm_device *dev;

	dev_priv = container_of(work, drm_i915_private_t,
				mm.retire_work.work);
	dev = dev_priv->dev;

	mutex_lock(&dev->struct_mutex);
	i915_gem_retire_requests(dev);
	if (!dev_priv->mm.suspended &&
	    !list_empty(&dev_priv->mm.request_list))
		schedule_delayed_work(&dev_priv->mm.retire_work, HZ);
	mutex_unlock(&dev->struct_mutex);
}

/**
 * Waits for a sequence number to be signaled, and cleans up the
 * request and object lists appropriately for that event.
 */
static int
i915_wait_request(struct drm_device *dev, uint32_t seqno)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	int ret = 0;

	BUG_ON(seqno == 0);

	if (!i915_seqno_passed(i915_get_gem_seqno(dev), seqno)) {
		dev_priv->mm.waiting_gem_seqno = seqno;
		i915_user_irq_get(dev);
		ret = wait_event_interruptible(dev_priv->irq_queue,
					       i915_seqno_passed(i915_get_gem_seqno(dev),
								 seqno) ||
					       dev_priv->mm.wedged);
		i915_user_irq_put(dev);
		dev_priv->mm.waiting_gem_seqno = 0;
	}
	if (dev_priv->mm.wedged)
		ret = -EIO;

	if (ret && ret != -ERESTARTSYS)
		DRM_ERROR("%s returns %d (awaiting %d at %d)\n",
			  __func__, ret, seqno, i915_get_gem_seqno(dev));

	/* Directly dispatch request retiring.  While we have the work queue
	 * to handle this, the waiter on a request often wants an associated
	 * buffer to have made it to the inactive list, and we would need
	 * a separate wait queue to handle that.
	 */
	if (ret == 0)
		i915_gem_retire_requests(dev);

	return ret;
}

static void
i915_gem_flush(struct drm_device *dev,
	       uint32_t invalidate_domains,
	       uint32_t flush_domains)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	uint32_t cmd;
	RING_LOCALS;

#if WATCH_EXEC
	DRM_INFO("%s: invalidate %08x flush %08x\n", __func__,
		  invalidate_domains, flush_domains);
#endif

	if (flush_domains & I915_GEM_DOMAIN_CPU)
		drm_agp_chipset_flush(dev);

	if ((invalidate_domains | flush_domains) & ~(I915_GEM_DOMAIN_CPU |
						     I915_GEM_DOMAIN_GTT)) {
		/*
		 * read/write caches:
		 *
		 * I915_GEM_DOMAIN_RENDER is always invalidated, but is
		 * only flushed if MI_NO_WRITE_FLUSH is unset.  On 965, it is
		 * also flushed at 2d versus 3d pipeline switches.
		 *
		 * read-only caches:
		 *
		 * I915_GEM_DOMAIN_SAMPLER is flushed on pre-965 if
		 * MI_READ_FLUSH is set, and is always flushed on 965.
		 *
		 * I915_GEM_DOMAIN_COMMAND may not exist?
		 *
		 * I915_GEM_DOMAIN_INSTRUCTION, which exists on 965, is
		 * invalidated when MI_EXE_FLUSH is set.
		 *
		 * I915_GEM_DOMAIN_VERTEX, which exists on 965, is
		 * invalidated with every MI_FLUSH.
		 *
		 * TLBs:
		 *
		 * On 965, TLBs associated with I915_GEM_DOMAIN_COMMAND
		 * and I915_GEM_DOMAIN_CPU in are invalidated at PTE write and
		 * I915_GEM_DOMAIN_RENDER and I915_GEM_DOMAIN_SAMPLER
		 * are flushed at any MI_FLUSH.
		 */

		cmd = MI_FLUSH | MI_NO_WRITE_FLUSH;
		if ((invalidate_domains|flush_domains) &
		    I915_GEM_DOMAIN_RENDER)
			cmd &= ~MI_NO_WRITE_FLUSH;
		if (!IS_I965G(dev)) {
			/*
			 * On the 965, the sampler cache always gets flushed
			 * and this bit is reserved.
			 */
			if (invalidate_domains & I915_GEM_DOMAIN_SAMPLER)
				cmd |= MI_READ_FLUSH;
		}
		if (invalidate_domains & I915_GEM_DOMAIN_INSTRUCTION)
			cmd |= MI_EXE_FLUSH;

#if WATCH_EXEC
		DRM_INFO("%s: queue flush %08x to ring\n", __func__, cmd);
#endif
		BEGIN_LP_RING(2);
		OUT_RING(cmd);
		OUT_RING(0); /* noop */
		ADVANCE_LP_RING();
	}
}

/**
 * Ensures that all rendering to the object has completed and the object is
 * safe to unbind from the GTT or access from the CPU.
 */
static int
i915_gem_object_wait_rendering(struct drm_gem_object *obj)
{
	struct drm_device *dev = obj->dev;
	struct drm_i915_gem_object *obj_priv = obj->driver_private;
	int ret;

	/* If there are writes queued to the buffer, flush and
	 * create a new seqno to wait for.
	 */
	if (obj->write_domain & ~(I915_GEM_DOMAIN_CPU|I915_GEM_DOMAIN_GTT)) {
		uint32_t write_domain = obj->write_domain;
#if WATCH_BUF
		DRM_INFO("%s: flushing object %p from write domain %08x\n",
			  __func__, obj, write_domain);
#endif
		i915_gem_flush(dev, 0, write_domain);

		i915_gem_object_move_to_active(obj);
		obj_priv->last_rendering_seqno = i915_add_request(dev,
								  write_domain);
		BUG_ON(obj_priv->last_rendering_seqno == 0);
#if WATCH_LRU
		DRM_INFO("%s: flush moves to exec list %p\n", __func__, obj);
#endif
	}

	/* If there is rendering queued on the buffer being evicted, wait for
	 * it.
	 */
	if (obj_priv->active) {
#if WATCH_BUF
		DRM_INFO("%s: object %p wait for seqno %08x\n",
			  __func__, obj, obj_priv->last_rendering_seqno);
#endif
		ret = i915_wait_request(dev, obj_priv->last_rendering_seqno);
		if (ret != 0)
			return ret;
	}

	return 0;
}

/**
 * Unbinds an object from the GTT aperture.
 */
static int
i915_gem_object_unbind(struct drm_gem_object *obj)
{
	struct drm_device *dev = obj->dev;
	struct drm_i915_gem_object *obj_priv = obj->driver_private;
	int ret = 0;

#if WATCH_BUF
	DRM_INFO("%s:%d %p\n", __func__, __LINE__, obj);
	DRM_INFO("gtt_space %p\n", obj_priv->gtt_space);
#endif
	if (obj_priv->gtt_space == NULL)
		return 0;

	if (obj_priv->pin_count != 0) {
		DRM_ERROR("Attempting to unbind pinned buffer\n");
		return -EINVAL;
	}

	/* Wait for any rendering to complete
	 */
	ret = i915_gem_object_wait_rendering(obj);
	if (ret) {
		DRM_ERROR("wait_rendering failed: %d\n", ret);
		return ret;
	}

	/* Move the object to the CPU domain to ensure that
	 * any possible CPU writes while it's not in the GTT
	 * are flushed when we go to remap it. This will
	 * also ensure that all pending GPU writes are finished
	 * before we unbind.
	 */
	ret = i915_gem_object_set_domain(obj, I915_GEM_DOMAIN_CPU,
					 I915_GEM_DOMAIN_CPU);
	if (ret) {
		DRM_ERROR("set_domain failed: %d\n", ret);
		return ret;
	}

	if (obj_priv->agp_mem != NULL) {
		drm_unbind_agp(obj_priv->agp_mem);
		drm_free_agp(obj_priv->agp_mem, obj->size / PAGE_SIZE);
		obj_priv->agp_mem = NULL;
	}

	BUG_ON(obj_priv->active);

	i915_gem_object_free_page_list(obj);

	if (obj_priv->gtt_space) {
		atomic_dec(&dev->gtt_count);
		atomic_sub(obj->size, &dev->gtt_memory);

		drm_mm_put_block(obj_priv->gtt_space);
		obj_priv->gtt_space = NULL;
	}

	/* Remove ourselves from the LRU list if present. */
	if (!list_empty(&obj_priv->list))
		list_del_init(&obj_priv->list);

	return 0;
}

static int
i915_gem_evict_something(struct drm_device *dev)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	struct drm_gem_object *obj;
	struct drm_i915_gem_object *obj_priv;
	int ret = 0;

	for (;;) {
		/* If there's an inactive buffer available now, grab it
		 * and be done.
		 */
		if (!list_empty(&dev_priv->mm.inactive_list)) {
			obj_priv = list_first_entry(&dev_priv->mm.inactive_list,
						    struct drm_i915_gem_object,
						    list);
			obj = obj_priv->obj;
			BUG_ON(obj_priv->pin_count != 0);
#if WATCH_LRU
			DRM_INFO("%s: evicting %p\n", __func__, obj);
#endif
			BUG_ON(obj_priv->active);

			/* Wait on the rendering and unbind the buffer. */
			ret = i915_gem_object_unbind(obj);
			break;
		}

		/* If we didn't get anything, but the ring is still processing
		 * things, wait for one of those things to finish and hopefully
		 * leave us a buffer to evict.
		 */
		if (!list_empty(&dev_priv->mm.request_list)) {
			struct drm_i915_gem_request *request;

			request = list_first_entry(&dev_priv->mm.request_list,
						   struct drm_i915_gem_request,
						   list);

			ret = i915_wait_request(dev, request->seqno);
			if (ret)
				break;

			/* if waiting caused an object to become inactive,
			 * then loop around and wait for it. Otherwise, we
			 * assume that waiting freed and unbound something,
			 * so there should now be some space in the GTT
			 */
			if (!list_empty(&dev_priv->mm.inactive_list))
				continue;
			break;
		}

		/* If we didn't have anything on the request list but there
		 * are buffers awaiting a flush, emit one and try again.
		 * When we wait on it, those buffers waiting for that flush
		 * will get moved to inactive.
		 */
		if (!list_empty(&dev_priv->mm.flushing_list)) {
			obj_priv = list_first_entry(&dev_priv->mm.flushing_list,
						    struct drm_i915_gem_object,
						    list);
			obj = obj_priv->obj;

			i915_gem_flush(dev,
				       obj->write_domain,
				       obj->write_domain);
			i915_add_request(dev, obj->write_domain);

			obj = NULL;
			continue;
		}

		DRM_ERROR("inactive empty %d request empty %d "
			  "flushing empty %d\n",
			  list_empty(&dev_priv->mm.inactive_list),
			  list_empty(&dev_priv->mm.request_list),
			  list_empty(&dev_priv->mm.flushing_list));
		/* If we didn't do any of the above, there's nothing to be done
		 * and we just can't fit it in.
		 */
		return -ENOMEM;
	}
	return ret;
}

static int
i915_gem_object_get_page_list(struct drm_gem_object *obj)
{
	struct drm_i915_gem_object *obj_priv = obj->driver_private;
	int page_count, i;
	struct address_space *mapping;
	struct inode *inode;
	struct page *page;
	int ret;

	if (obj_priv->page_list)
		return 0;

	/* Get the list of pages out of our struct file.  They'll be pinned
	 * at this point until we release them.
	 */
	page_count = obj->size / PAGE_SIZE;
	BUG_ON(obj_priv->page_list != NULL);
	obj_priv->page_list = drm_calloc(page_count, sizeof(struct page *),
					 DRM_MEM_DRIVER);
	if (obj_priv->page_list == NULL) {
		DRM_ERROR("Faled to allocate page list\n");
		return -ENOMEM;
	}

	inode = obj->filp->f_path.dentry->d_inode;
	mapping = inode->i_mapping;
	for (i = 0; i < page_count; i++) {
		page = read_mapping_page(mapping, i, NULL);
		if (IS_ERR(page)) {
			ret = PTR_ERR(page);
			DRM_ERROR("read_mapping_page failed: %d\n", ret);
			i915_gem_object_free_page_list(obj);
			return ret;
		}
		obj_priv->page_list[i] = page;
	}
	return 0;
}

/**
 * Finds free space in the GTT aperture and binds the object there.
 */
static int
i915_gem_object_bind_to_gtt(struct drm_gem_object *obj, unsigned alignment)
{
	struct drm_device *dev = obj->dev;
	drm_i915_private_t *dev_priv = dev->dev_private;
	struct drm_i915_gem_object *obj_priv = obj->driver_private;
	struct drm_mm_node *free_space;
	int page_count, ret;

	if (alignment == 0)
		alignment = PAGE_SIZE;
	if (alignment & (PAGE_SIZE - 1)) {
		DRM_ERROR("Invalid object alignment requested %u\n", alignment);
		return -EINVAL;
	}

 search_free:
	free_space = drm_mm_search_free(&dev_priv->mm.gtt_space,
					obj->size, alignment, 0);
	if (free_space != NULL) {
		obj_priv->gtt_space = drm_mm_get_block(free_space, obj->size,
						       alignment);
		if (obj_priv->gtt_space != NULL) {
			obj_priv->gtt_space->private = obj;
			obj_priv->gtt_offset = obj_priv->gtt_space->start;
		}
	}
	if (obj_priv->gtt_space == NULL) {
		/* If the gtt is empty and we're still having trouble
		 * fitting our object in, we're out of memory.
		 */
#if WATCH_LRU
		DRM_INFO("%s: GTT full, evicting something\n", __func__);
#endif
		if (list_empty(&dev_priv->mm.inactive_list) &&
		    list_empty(&dev_priv->mm.flushing_list) &&
		    list_empty(&dev_priv->mm.active_list)) {
			DRM_ERROR("GTT full, but LRU list empty\n");
			return -ENOMEM;
		}

		ret = i915_gem_evict_something(dev);
		if (ret != 0) {
			DRM_ERROR("Failed to evict a buffer %d\n", ret);
			return ret;
		}
		goto search_free;
	}

#if WATCH_BUF
	DRM_INFO("Binding object of size %d at 0x%08x\n",
		 obj->size, obj_priv->gtt_offset);
#endif
	ret = i915_gem_object_get_page_list(obj);
	if (ret) {
		drm_mm_put_block(obj_priv->gtt_space);
		obj_priv->gtt_space = NULL;
		return ret;
	}

	page_count = obj->size / PAGE_SIZE;
	/* Create an AGP memory structure pointing at our pages, and bind it
	 * into the GTT.
	 */
	obj_priv->agp_mem = drm_agp_bind_pages(dev,
					       obj_priv->page_list,
					       page_count,
					       obj_priv->gtt_offset,
					       obj_priv->agp_type);
	if (obj_priv->agp_mem == NULL) {
		i915_gem_object_free_page_list(obj);
		drm_mm_put_block(obj_priv->gtt_space);
		obj_priv->gtt_space = NULL;
		return -ENOMEM;
	}
	atomic_inc(&dev->gtt_count);
	atomic_add(obj->size, &dev->gtt_memory);

	/* Assert that the object is not currently in any GPU domain. As it
	 * wasn't in the GTT, there shouldn't be any way it could have been in
	 * a GPU cache
	 */
	BUG_ON(obj->read_domains & ~(I915_GEM_DOMAIN_CPU|I915_GEM_DOMAIN_GTT));
	BUG_ON(obj->write_domain & ~(I915_GEM_DOMAIN_CPU|I915_GEM_DOMAIN_GTT));

	return 0;
}

void
i915_gem_clflush_object(struct drm_gem_object *obj)
{
	struct drm_i915_gem_object	*obj_priv = obj->driver_private;

	/* If we don't have a page list set up, then we're not pinned
	 * to GPU, and we can ignore the cache flush because it'll happen
	 * again at bind time.
	 */
	if (obj_priv->page_list == NULL)
		return;

	drm_clflush_pages(obj_priv->page_list, obj->size / PAGE_SIZE);
}

/*
 * Set the next domain for the specified object. This
 * may not actually perform the necessary flushing/invaliding though,
 * as that may want to be batched with other set_domain operations
 *
 * This is (we hope) the only really tricky part of gem. The goal
 * is fairly simple -- track which caches hold bits of the object
 * and make sure they remain coherent. A few concrete examples may
 * help to explain how it works. For shorthand, we use the notation
 * (read_domains, write_domain), e.g. (CPU, CPU) to indicate the
 * a pair of read and write domain masks.
 *
 * Case 1: the batch buffer
 *
 *	1. Allocated
 *	2. Written by CPU
 *	3. Mapped to GTT
 *	4. Read by GPU
 *	5. Unmapped from GTT
 *	6. Freed
 *
 *	Let's take these a step at a time
 *
 *	1. Allocated
 *		Pages allocated from the kernel may still have
 *		cache contents, so we set them to (CPU, CPU) always.
 *	2. Written by CPU (using pwrite)
 *		The pwrite function calls set_domain (CPU, CPU) and
 *		this function does nothing (as nothing changes)
 *	3. Mapped by GTT
 *		This function asserts that the object is not
 *		currently in any GPU-based read or write domains
 *	4. Read by GPU
 *		i915_gem_execbuffer calls set_domain (COMMAND, 0).
 *		As write_domain is zero, this function adds in the
 *		current read domains (CPU+COMMAND, 0).
 *		flush_domains is set to CPU.
 *		invalidate_domains is set to COMMAND
 *		clflush is run to get data out of the CPU caches
 *		then i915_dev_set_domain calls i915_gem_flush to
 *		emit an MI_FLUSH and drm_agp_chipset_flush
 *	5. Unmapped from GTT
 *		i915_gem_object_unbind calls set_domain (CPU, CPU)
 *		flush_domains and invalidate_domains end up both zero
 *		so no flushing/invalidating happens
 *	6. Freed
 *		yay, done
 *
 * Case 2: The shared render buffer
 *
 *	1. Allocated
 *	2. Mapped to GTT
 *	3. Read/written by GPU
 *	4. set_domain to (CPU,CPU)
 *	5. Read/written by CPU
 *	6. Read/written by GPU
 *
 *	1. Allocated
 *		Same as last example, (CPU, CPU)
 *	2. Mapped to GTT
 *		Nothing changes (assertions find that it is not in the GPU)
 *	3. Read/written by GPU
 *		execbuffer calls set_domain (RENDER, RENDER)
 *		flush_domains gets CPU
 *		invalidate_domains gets GPU
 *		clflush (obj)
 *		MI_FLUSH and drm_agp_chipset_flush
 *	4. set_domain (CPU, CPU)
 *		flush_domains gets GPU
 *		invalidate_domains gets CPU
 *		wait_rendering (obj) to make sure all drawing is complete.
 *		This will include an MI_FLUSH to get the data from GPU
 *		to memory
 *		clflush (obj) to invalidate the CPU cache
 *		Another MI_FLUSH in i915_gem_flush (eliminate this somehow?)
 *	5. Read/written by CPU
 *		cache lines are loaded and dirtied
 *	6. Read written by GPU
 *		Same as last GPU access
 *
 * Case 3: The constant buffer
 *
 *	1. Allocated
 *	2. Written by CPU
 *	3. Read by GPU
 *	4. Updated (written) by CPU again
 *	5. Read by GPU
 *
 *	1. Allocated
 *		(CPU, CPU)
 *	2. Written by CPU
 *		(CPU, CPU)
 *	3. Read by GPU
 *		(CPU+RENDER, 0)
 *		flush_domains = CPU
 *		invalidate_domains = RENDER
 *		clflush (obj)
 *		MI_FLUSH
 *		drm_agp_chipset_flush
 *	4. Updated (written) by CPU again
 *		(CPU, CPU)
 *		flush_domains = 0 (no previous write domain)
 *		invalidate_domains = 0 (no new read domains)
 *	5. Read by GPU
 *		(CPU+RENDER, 0)
 *		flush_domains = CPU
 *		invalidate_domains = RENDER
 *		clflush (obj)
 *		MI_FLUSH
 *		drm_agp_chipset_flush
 */
static int
i915_gem_object_set_domain(struct drm_gem_object *obj,
			    uint32_t read_domains,
			    uint32_t write_domain)
{
	struct drm_device		*dev = obj->dev;
	struct drm_i915_gem_object	*obj_priv = obj->driver_private;
	uint32_t			invalidate_domains = 0;
	uint32_t			flush_domains = 0;
	int				ret;

#if WATCH_BUF
	DRM_INFO("%s: object %p read %08x -> %08x write %08x -> %08x\n",
		 __func__, obj,
		 obj->read_domains, read_domains,
		 obj->write_domain, write_domain);
#endif
	/*
	 * If the object isn't moving to a new write domain,
	 * let the object stay in multiple read domains
	 */
	if (write_domain == 0)
		read_domains |= obj->read_domains;
	else
		obj_priv->dirty = 1;

	/*
	 * Flush the current write domain if
	 * the new read domains don't match. Invalidate
	 * any read domains which differ from the old
	 * write domain
	 */
	if (obj->write_domain && obj->write_domain != read_domains) {
		flush_domains |= obj->write_domain;
		invalidate_domains |= read_domains & ~obj->write_domain;
	}
	/*
	 * Invalidate any read caches which may have
	 * stale data. That is, any new read domains.
	 */
	invalidate_domains |= read_domains & ~obj->read_domains;
	if ((flush_domains | invalidate_domains) & I915_GEM_DOMAIN_CPU) {
#if WATCH_BUF
		DRM_INFO("%s: CPU domain flush %08x invalidate %08x\n",
			 __func__, flush_domains, invalidate_domains);
#endif
		/*
		 * If we're invaliding the CPU cache and flushing a GPU cache,
		 * then pause for rendering so that the GPU caches will be
		 * flushed before the cpu cache is invalidated
		 */
		if ((invalidate_domains & I915_GEM_DOMAIN_CPU) &&
		    (flush_domains & ~(I915_GEM_DOMAIN_CPU |
				       I915_GEM_DOMAIN_GTT))) {
			ret = i915_gem_object_wait_rendering(obj);
			if (ret)
				return ret;
		}
		i915_gem_clflush_object(obj);
	}

	if ((write_domain | flush_domains) != 0)
		obj->write_domain = write_domain;

	/* If we're invalidating the CPU domain, clear the per-page CPU
	 * domain list as well.
	 */
	if (obj_priv->page_cpu_valid != NULL &&
	    (write_domain != 0 ||
	     read_domains & I915_GEM_DOMAIN_CPU)) {
		drm_free(obj_priv->page_cpu_valid, obj->size / PAGE_SIZE,
			 DRM_MEM_DRIVER);
		obj_priv->page_cpu_valid = NULL;
	}
	obj->read_domains = read_domains;

	dev->invalidate_domains |= invalidate_domains;
	dev->flush_domains |= flush_domains;
#if WATCH_BUF
	DRM_INFO("%s: read %08x write %08x invalidate %08x flush %08x\n",
		 __func__,
		 obj->read_domains, obj->write_domain,
		 dev->invalidate_domains, dev->flush_domains);
#endif
	return 0;
}

/**
 * Set the read/write domain on a range of the object.
 *
 * Currently only implemented for CPU reads, otherwise drops to normal
 * i915_gem_object_set_domain().
 */
static int
i915_gem_object_set_domain_range(struct drm_gem_object *obj,
				 uint64_t offset,
				 uint64_t size,
				 uint32_t read_domains,
				 uint32_t write_domain)
{
	struct drm_i915_gem_object *obj_priv = obj->driver_private;
	int ret, i;

	if (obj->read_domains & I915_GEM_DOMAIN_CPU)
		return 0;

	if (read_domains != I915_GEM_DOMAIN_CPU ||
	    write_domain != 0)
		return i915_gem_object_set_domain(obj,
						  read_domains, write_domain);

	/* Wait on any GPU rendering to the object to be flushed. */
	ret = i915_gem_object_wait_rendering(obj);
	if (ret)
		return ret;

	if (obj_priv->page_cpu_valid == NULL) {
		obj_priv->page_cpu_valid = drm_calloc(1, obj->size / PAGE_SIZE,
						      DRM_MEM_DRIVER);
	}

	/* Flush the cache on any pages that are still invalid from the CPU's
	 * perspective.
	 */
	for (i = offset / PAGE_SIZE; i <= (offset + size - 1) / PAGE_SIZE; i++) {
		if (obj_priv->page_cpu_valid[i])
			continue;

		drm_clflush_pages(obj_priv->page_list + i, 1);

		obj_priv->page_cpu_valid[i] = 1;
	}

	return 0;
}

/**
 * Once all of the objects have been set in the proper domain,
 * perform the necessary flush and invalidate operations.
 *
 * Returns the write domains flushed, for use in flush tracking.
 */
static uint32_t
i915_gem_dev_set_domain(struct drm_device *dev)
{
	uint32_t flush_domains = dev->flush_domains;

	/*
	 * Now that all the buffers are synced to the proper domains,
	 * flush and invalidate the collected domains
	 */
	if (dev->invalidate_domains | dev->flush_domains) {
#if WATCH_EXEC
		DRM_INFO("%s: invalidate_domains %08x flush_domains %08x\n",
			  __func__,
			 dev->invalidate_domains,
			 dev->flush_domains);
#endif
		i915_gem_flush(dev,
			       dev->invalidate_domains,
			       dev->flush_domains);
		dev->invalidate_domains = 0;
		dev->flush_domains = 0;
	}

	return flush_domains;
}

/**
 * Pin an object to the GTT and evaluate the relocations landing in it.
 */
static int
i915_gem_object_pin_and_relocate(struct drm_gem_object *obj,
				 struct drm_file *file_priv,
				 struct drm_i915_gem_exec_object *entry)
{
	struct drm_device *dev = obj->dev;
	drm_i915_private_t *dev_priv = dev->dev_private;
	struct drm_i915_gem_relocation_entry reloc;
	struct drm_i915_gem_relocation_entry __user *relocs;
	struct drm_i915_gem_object *obj_priv = obj->driver_private;
	int i, ret;
	void __iomem *reloc_page;

	/* Choose the GTT offset for our buffer and put it there. */
	ret = i915_gem_object_pin(obj, (uint32_t) entry->alignment);
	if (ret)
		return ret;

	entry->offset = obj_priv->gtt_offset;

	relocs = (struct drm_i915_gem_relocation_entry __user *)
		 (uintptr_t) entry->relocs_ptr;
	/* Apply the relocations, using the GTT aperture to avoid cache
	 * flushing requirements.
	 */
	for (i = 0; i < entry->relocation_count; i++) {
		struct drm_gem_object *target_obj;
		struct drm_i915_gem_object *target_obj_priv;
		uint32_t reloc_val, reloc_offset;
		uint32_t __iomem *reloc_entry;

		ret = copy_from_user(&reloc, relocs + i, sizeof(reloc));
		if (ret != 0) {
			i915_gem_object_unpin(obj);
			return ret;
		}

		target_obj = drm_gem_object_lookup(obj->dev, file_priv,
						   reloc.target_handle);
		if (target_obj == NULL) {
			i915_gem_object_unpin(obj);
			return -EBADF;
		}
		target_obj_priv = target_obj->driver_private;

		/* The target buffer should have appeared before us in the
		 * exec_object list, so it should have a GTT space bound by now.
		 */
		if (target_obj_priv->gtt_space == NULL) {
			DRM_ERROR("No GTT space found for object %d\n",
				  reloc.target_handle);
			drm_gem_object_unreference(target_obj);
			i915_gem_object_unpin(obj);
			return -EINVAL;
		}

		if (reloc.offset > obj->size - 4) {
			DRM_ERROR("Relocation beyond object bounds: "
				  "obj %p target %d offset %d size %d.\n",
				  obj, reloc.target_handle,
				  (int) reloc.offset, (int) obj->size);
			drm_gem_object_unreference(target_obj);
			i915_gem_object_unpin(obj);
			return -EINVAL;
		}
		if (reloc.offset & 3) {
			DRM_ERROR("Relocation not 4-byte aligned: "
				  "obj %p target %d offset %d.\n",
				  obj, reloc.target_handle,
				  (int) reloc.offset);
			drm_gem_object_unreference(target_obj);
			i915_gem_object_unpin(obj);
			return -EINVAL;
		}

		if (reloc.write_domain && target_obj->pending_write_domain &&
		    reloc.write_domain != target_obj->pending_write_domain) {
			DRM_ERROR("Write domain conflict: "
				  "obj %p target %d offset %d "
				  "new %08x old %08x\n",
				  obj, reloc.target_handle,
				  (int) reloc.offset,
				  reloc.write_domain,
				  target_obj->pending_write_domain);
			drm_gem_object_unreference(target_obj);
			i915_gem_object_unpin(obj);
			return -EINVAL;
		}

#if WATCH_RELOC
		DRM_INFO("%s: obj %p offset %08x target %d "
			 "read %08x write %08x gtt %08x "
			 "presumed %08x delta %08x\n",
			 __func__,
			 obj,
			 (int) reloc.offset,
			 (int) reloc.target_handle,
			 (int) reloc.read_domains,
			 (int) reloc.write_domain,
			 (int) target_obj_priv->gtt_offset,
			 (int) reloc.presumed_offset,
			 reloc.delta);
#endif

		target_obj->pending_read_domains |= reloc.read_domains;
		target_obj->pending_write_domain |= reloc.write_domain;

		/* If the relocation already has the right value in it, no
		 * more work needs to be done.
		 */
		if (target_obj_priv->gtt_offset == reloc.presumed_offset) {
			drm_gem_object_unreference(target_obj);
			continue;
		}

		/* Now that we're going to actually write some data in,
		 * make sure that any rendering using this buffer's contents
		 * is completed.
		 */
		i915_gem_object_wait_rendering(obj);

		/* As we're writing through the gtt, flush
		 * any CPU writes before we write the relocations
		 */
		if (obj->write_domain & I915_GEM_DOMAIN_CPU) {
			i915_gem_clflush_object(obj);
			drm_agp_chipset_flush(dev);
			obj->write_domain = 0;
		}

		/* Map the page containing the relocation we're going to
		 * perform.
		 */
		reloc_offset = obj_priv->gtt_offset + reloc.offset;
		reloc_page = io_mapping_map_atomic_wc(dev_priv->mm.gtt_mapping,
						      (reloc_offset &
						       ~(PAGE_SIZE - 1)));
		reloc_entry = (uint32_t __iomem *)(reloc_page +
						   (reloc_offset & (PAGE_SIZE - 1)));
		reloc_val = target_obj_priv->gtt_offset + reloc.delta;

#if WATCH_BUF
		DRM_INFO("Applied relocation: %p@0x%08x %08x -> %08x\n",
			  obj, (unsigned int) reloc.offset,
			  readl(reloc_entry), reloc_val);
#endif
		writel(reloc_val, reloc_entry);
		io_mapping_unmap_atomic(reloc_page);

		/* Write the updated presumed offset for this entry back out
		 * to the user.
		 */
		reloc.presumed_offset = target_obj_priv->gtt_offset;
		ret = copy_to_user(relocs + i, &reloc, sizeof(reloc));
		if (ret != 0) {
			drm_gem_object_unreference(target_obj);
			i915_gem_object_unpin(obj);
			return ret;
		}

		drm_gem_object_unreference(target_obj);
	}

#if WATCH_BUF
	if (0)
		i915_gem_dump_object(obj, 128, __func__, ~0);
#endif
	return 0;
}

/** Dispatch a batchbuffer to the ring
 */
static int
i915_dispatch_gem_execbuffer(struct drm_device *dev,
			      struct drm_i915_gem_execbuffer *exec,
			      uint64_t exec_offset)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	struct drm_clip_rect __user *boxes = (struct drm_clip_rect __user *)
					     (uintptr_t) exec->cliprects_ptr;
	int nbox = exec->num_cliprects;
	int i = 0, count;
	uint32_t	exec_start, exec_len;
	RING_LOCALS;

	exec_start = (uint32_t) exec_offset + exec->batch_start_offset;
	exec_len = (uint32_t) exec->batch_len;

	if ((exec_start | exec_len) & 0x7) {
		DRM_ERROR("alignment\n");
		return -EINVAL;
	}

	if (!exec_start)
		return -EINVAL;

	count = nbox ? nbox : 1;

	for (i = 0; i < count; i++) {
		if (i < nbox) {
			int ret = i915_emit_box(dev, boxes, i,
						exec->DR1, exec->DR4);
			if (ret)
				return ret;
		}

		if (IS_I830(dev) || IS_845G(dev)) {
			BEGIN_LP_RING(4);
			OUT_RING(MI_BATCH_BUFFER);
			OUT_RING(exec_start | MI_BATCH_NON_SECURE);
			OUT_RING(exec_start + exec_len - 4);
			OUT_RING(0);
			ADVANCE_LP_RING();
		} else {
			BEGIN_LP_RING(2);
			if (IS_I965G(dev)) {
				OUT_RING(MI_BATCH_BUFFER_START |
					 (2 << 6) |
					 MI_BATCH_NON_SECURE_I965);
				OUT_RING(exec_start);
			} else {
				OUT_RING(MI_BATCH_BUFFER_START |
					 (2 << 6));
				OUT_RING(exec_start | MI_BATCH_NON_SECURE);
			}
			ADVANCE_LP_RING();
		}
	}

	/* XXX breadcrumb */
	return 0;
}

/* Throttle our rendering by waiting until the ring has completed our requests
 * emitted over 20 msec ago.
 *
 * This should get us reasonable parallelism between CPU and GPU but also
 * relatively low latency when blocking on a particular request to finish.
 */
static int
i915_gem_ring_throttle(struct drm_device *dev, struct drm_file *file_priv)
{
	struct drm_i915_file_private *i915_file_priv = file_priv->driver_priv;
	int ret = 0;
	uint32_t seqno;

	mutex_lock(&dev->struct_mutex);
	seqno = i915_file_priv->mm.last_gem_throttle_seqno;
	i915_file_priv->mm.last_gem_throttle_seqno =
		i915_file_priv->mm.last_gem_seqno;
	if (seqno)
		ret = i915_wait_request(dev, seqno);
	mutex_unlock(&dev->struct_mutex);
	return ret;
}

int
i915_gem_execbuffer(struct drm_device *dev, void *data,
		    struct drm_file *file_priv)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	struct drm_i915_file_private *i915_file_priv = file_priv->driver_priv;
	struct drm_i915_gem_execbuffer *args = data;
	struct drm_i915_gem_exec_object *exec_list = NULL;
	struct drm_gem_object **object_list = NULL;
	struct drm_gem_object *batch_obj;
	int ret, i, pinned = 0;
	uint64_t exec_offset;
	uint32_t seqno, flush_domains;

#if WATCH_EXEC
	DRM_INFO("buffers_ptr %d buffer_count %d len %08x\n",
		  (int) args->buffers_ptr, args->buffer_count, args->batch_len);
#endif

	if (args->buffer_count < 1) {
		DRM_ERROR("execbuf with %d buffers\n", args->buffer_count);
		return -EINVAL;
	}
	/* Copy in the exec list from userland */
	exec_list = drm_calloc(sizeof(*exec_list), args->buffer_count,
			       DRM_MEM_DRIVER);
	object_list = drm_calloc(sizeof(*object_list), args->buffer_count,
				 DRM_MEM_DRIVER);
	if (exec_list == NULL || object_list == NULL) {
		DRM_ERROR("Failed to allocate exec or object list "
			  "for %d buffers\n",
			  args->buffer_count);
		ret = -ENOMEM;
		goto pre_mutex_err;
	}
	ret = copy_from_user(exec_list,
			     (struct drm_i915_relocation_entry __user *)
			     (uintptr_t) args->buffers_ptr,
			     sizeof(*exec_list) * args->buffer_count);
	if (ret != 0) {
		DRM_ERROR("copy %d exec entries failed %d\n",
			  args->buffer_count, ret);
		goto pre_mutex_err;
	}

	mutex_lock(&dev->struct_mutex);

	i915_verify_inactive(dev, __FILE__, __LINE__);

	if (dev_priv->mm.wedged) {
		DRM_ERROR("Execbuf while wedged\n");
		mutex_unlock(&dev->struct_mutex);
		return -EIO;
	}

	if (dev_priv->mm.suspended) {
		DRM_ERROR("Execbuf while VT-switched.\n");
		mutex_unlock(&dev->struct_mutex);
		return -EBUSY;
	}

	/* Zero the gloabl flush/invalidate flags. These
	 * will be modified as each object is bound to the
	 * gtt
	 */
	dev->invalidate_domains = 0;
	dev->flush_domains = 0;

	/* Look up object handles and perform the relocations */
	for (i = 0; i < args->buffer_count; i++) {
		object_list[i] = drm_gem_object_lookup(dev, file_priv,
						       exec_list[i].handle);
		if (object_list[i] == NULL) {
			DRM_ERROR("Invalid object handle %d at index %d\n",
				   exec_list[i].handle, i);
			ret = -EBADF;
			goto err;
		}

		object_list[i]->pending_read_domains = 0;
		object_list[i]->pending_write_domain = 0;
		ret = i915_gem_object_pin_and_relocate(object_list[i],
						       file_priv,
						       &exec_list[i]);
		if (ret) {
			DRM_ERROR("object bind and relocate failed %d\n", ret);
			goto err;
		}
		pinned = i + 1;
	}

	/* Set the pending read domains for the batch buffer to COMMAND */
	batch_obj = object_list[args->buffer_count-1];
	batch_obj->pending_read_domains = I915_GEM_DOMAIN_COMMAND;
	batch_obj->pending_write_domain = 0;

	i915_verify_inactive(dev, __FILE__, __LINE__);

	for (i = 0; i < args->buffer_count; i++) {
		struct drm_gem_object *obj = object_list[i];
		struct drm_i915_gem_object *obj_priv = obj->driver_private;

		if (obj_priv->gtt_space == NULL) {
			/* We evicted the buffer in the process of validating
			 * our set of buffers in.  We could try to recover by
			 * kicking them everything out and trying again from
			 * the start.
			 */
			ret = -ENOMEM;
			goto err;
		}

		/* make sure all previous memory operations have passed */
		ret = i915_gem_object_set_domain(obj,
						 obj->pending_read_domains,
						 obj->pending_write_domain);
		if (ret)
			goto err;
	}

	i915_verify_inactive(dev, __FILE__, __LINE__);

	/* Flush/invalidate caches and chipset buffer */
	flush_domains = i915_gem_dev_set_domain(dev);

	i915_verify_inactive(dev, __FILE__, __LINE__);

#if WATCH_COHERENCY
	for (i = 0; i < args->buffer_count; i++) {
		i915_gem_object_check_coherency(object_list[i],
						exec_list[i].handle);
	}
#endif

	exec_offset = exec_list[args->buffer_count - 1].offset;

#if WATCH_EXEC
	i915_gem_dump_object(object_list[args->buffer_count - 1],
			      args->batch_len,
			      __func__,
			      ~0);
#endif

	(void)i915_add_request(dev, flush_domains);

	/* Exec the batchbuffer */
	ret = i915_dispatch_gem_execbuffer(dev, args, exec_offset);
	if (ret) {
		DRM_ERROR("dispatch failed %d\n", ret);
		goto err;
	}

	/*
	 * Ensure that the commands in the batch buffer are
	 * finished before the interrupt fires
	 */
	flush_domains = i915_retire_commands(dev);

	i915_verify_inactive(dev, __FILE__, __LINE__);

	/*
	 * Get a seqno representing the execution of the current buffer,
	 * which we can wait on.  We would like to mitigate these interrupts,
	 * likely by only creating seqnos occasionally (so that we have
	 * *some* interrupts representing completion of buffers that we can
	 * wait on when trying to clear up gtt space).
	 */
	seqno = i915_add_request(dev, flush_domains);
	BUG_ON(seqno == 0);
	i915_file_priv->mm.last_gem_seqno = seqno;
	for (i = 0; i < args->buffer_count; i++) {
		struct drm_gem_object *obj = object_list[i];
		struct drm_i915_gem_object *obj_priv = obj->driver_private;

		i915_gem_object_move_to_active(obj);
		obj_priv->last_rendering_seqno = seqno;
#if WATCH_LRU
		DRM_INFO("%s: move to exec list %p\n", __func__, obj);
#endif
	}
#if WATCH_LRU
	i915_dump_lru(dev, __func__);
#endif

	i915_verify_inactive(dev, __FILE__, __LINE__);

	/* Copy the new buffer offsets back to the user's exec list. */
	ret = copy_to_user((struct drm_i915_relocation_entry __user *)
			   (uintptr_t) args->buffers_ptr,
			   exec_list,
			   sizeof(*exec_list) * args->buffer_count);
	if (ret)
		DRM_ERROR("failed to copy %d exec entries "
			  "back to user (%d)\n",
			   args->buffer_count, ret);
err:
	if (object_list != NULL) {
		for (i = 0; i < pinned; i++)
			i915_gem_object_unpin(object_list[i]);

		for (i = 0; i < args->buffer_count; i++)
			drm_gem_object_unreference(object_list[i]);
	}
	mutex_unlock(&dev->struct_mutex);

pre_mutex_err:
	drm_free(object_list, sizeof(*object_list) * args->buffer_count,
		 DRM_MEM_DRIVER);
	drm_free(exec_list, sizeof(*exec_list) * args->buffer_count,
		 DRM_MEM_DRIVER);

	return ret;
}

int
i915_gem_object_pin(struct drm_gem_object *obj, uint32_t alignment)
{
	struct drm_device *dev = obj->dev;
	struct drm_i915_gem_object *obj_priv = obj->driver_private;
	int ret;

	i915_verify_inactive(dev, __FILE__, __LINE__);
	if (obj_priv->gtt_space == NULL) {
		ret = i915_gem_object_bind_to_gtt(obj, alignment);
		if (ret != 0) {
			DRM_ERROR("Failure to bind: %d", ret);
			return ret;
		}
	}
	obj_priv->pin_count++;

	/* If the object is not active and not pending a flush,
	 * remove it from the inactive list
	 */
	if (obj_priv->pin_count == 1) {
		atomic_inc(&dev->pin_count);
		atomic_add(obj->size, &dev->pin_memory);
		if (!obj_priv->active &&
		    (obj->write_domain & ~(I915_GEM_DOMAIN_CPU |
					   I915_GEM_DOMAIN_GTT)) == 0 &&
		    !list_empty(&obj_priv->list))
			list_del_init(&obj_priv->list);
	}
	i915_verify_inactive(dev, __FILE__, __LINE__);

	return 0;
}

void
i915_gem_object_unpin(struct drm_gem_object *obj)
{
	struct drm_device *dev = obj->dev;
	drm_i915_private_t *dev_priv = dev->dev_private;
	struct drm_i915_gem_object *obj_priv = obj->driver_private;

	i915_verify_inactive(dev, __FILE__, __LINE__);
	obj_priv->pin_count--;
	BUG_ON(obj_priv->pin_count < 0);
	BUG_ON(obj_priv->gtt_space == NULL);

	/* If the object is no longer pinned, and is
	 * neither active nor being flushed, then stick it on
	 * the inactive list
	 */
	if (obj_priv->pin_count == 0) {
		if (!obj_priv->active &&
		    (obj->write_domain & ~(I915_GEM_DOMAIN_CPU |
					   I915_GEM_DOMAIN_GTT)) == 0)
			list_move_tail(&obj_priv->list,
				       &dev_priv->mm.inactive_list);
		atomic_dec(&dev->pin_count);
		atomic_sub(obj->size, &dev->pin_memory);
	}
	i915_verify_inactive(dev, __FILE__, __LINE__);
}

int
i915_gem_pin_ioctl(struct drm_device *dev, void *data,
		   struct drm_file *file_priv)
{
	struct drm_i915_gem_pin *args = data;
	struct drm_gem_object *obj;
	struct drm_i915_gem_object *obj_priv;
	int ret;

	mutex_lock(&dev->struct_mutex);

	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
	if (obj == NULL) {
		DRM_ERROR("Bad handle in i915_gem_pin_ioctl(): %d\n",
			  args->handle);
		mutex_unlock(&dev->struct_mutex);
		return -EBADF;
	}
	obj_priv = obj->driver_private;

	ret = i915_gem_object_pin(obj, args->alignment);
	if (ret != 0) {
		drm_gem_object_unreference(obj);
		mutex_unlock(&dev->struct_mutex);
		return ret;
	}

	/* XXX - flush the CPU caches for pinned objects
	 * as the X server doesn't manage domains yet
	 */
	if (obj->write_domain & I915_GEM_DOMAIN_CPU) {
		i915_gem_clflush_object(obj);
		drm_agp_chipset_flush(dev);
		obj->write_domain = 0;
	}
	args->offset = obj_priv->gtt_offset;
	drm_gem_object_unreference(obj);
	mutex_unlock(&dev->struct_mutex);

	return 0;
}

int
i915_gem_unpin_ioctl(struct drm_device *dev, void *data,
		     struct drm_file *file_priv)
{
	struct drm_i915_gem_pin *args = data;
	struct drm_gem_object *obj;

	mutex_lock(&dev->struct_mutex);

	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
	if (obj == NULL) {
		DRM_ERROR("Bad handle in i915_gem_unpin_ioctl(): %d\n",
			  args->handle);
		mutex_unlock(&dev->struct_mutex);
		return -EBADF;
	}

	i915_gem_object_unpin(obj);

	drm_gem_object_unreference(obj);
	mutex_unlock(&dev->struct_mutex);
	return 0;
}

int
i915_gem_busy_ioctl(struct drm_device *dev, void *data,
		    struct drm_file *file_priv)
{
	struct drm_i915_gem_busy *args = data;
	struct drm_gem_object *obj;
	struct drm_i915_gem_object *obj_priv;

	mutex_lock(&dev->struct_mutex);
	obj = drm_gem_object_lookup(dev, file_priv, args->handle);
	if (obj == NULL) {
		DRM_ERROR("Bad handle in i915_gem_busy_ioctl(): %d\n",
			  args->handle);
		mutex_unlock(&dev->struct_mutex);
		return -EBADF;
	}

	obj_priv = obj->driver_private;
	args->busy = obj_priv->active;

	drm_gem_object_unreference(obj);
	mutex_unlock(&dev->struct_mutex);
	return 0;
}

int
i915_gem_throttle_ioctl(struct drm_device *dev, void *data,
			struct drm_file *file_priv)
{
    return i915_gem_ring_throttle(dev, file_priv);
}

int i915_gem_init_object(struct drm_gem_object *obj)
{
	struct drm_i915_gem_object *obj_priv;

	obj_priv = drm_calloc(1, sizeof(*obj_priv), DRM_MEM_DRIVER);
	if (obj_priv == NULL)
		return -ENOMEM;

	/*
	 * We've just allocated pages from the kernel,
	 * so they've just been written by the CPU with
	 * zeros. They'll need to be clflushed before we
	 * use them with the GPU.
	 */
	obj->write_domain = I915_GEM_DOMAIN_CPU;
	obj->read_domains = I915_GEM_DOMAIN_CPU;

	obj_priv->agp_type = AGP_USER_MEMORY;

	obj->driver_private = obj_priv;
	obj_priv->obj = obj;
	INIT_LIST_HEAD(&obj_priv->list);
	return 0;
}

void i915_gem_free_object(struct drm_gem_object *obj)
{
	struct drm_i915_gem_object *obj_priv = obj->driver_private;

	while (obj_priv->pin_count > 0)
		i915_gem_object_unpin(obj);

	i915_gem_object_unbind(obj);

	drm_free(obj_priv->page_cpu_valid, 1, DRM_MEM_DRIVER);
	drm_free(obj->driver_private, 1, DRM_MEM_DRIVER);
}

static int
i915_gem_set_domain(struct drm_gem_object *obj,
		    struct drm_file *file_priv,
		    uint32_t read_domains,
		    uint32_t write_domain)
{
	struct drm_device *dev = obj->dev;
	int ret;
	uint32_t flush_domains;

	BUG_ON(!mutex_is_locked(&dev->struct_mutex));

	ret = i915_gem_object_set_domain(obj, read_domains, write_domain);
	if (ret)
		return ret;
	flush_domains = i915_gem_dev_set_domain(obj->dev);

	if (flush_domains & ~(I915_GEM_DOMAIN_CPU|I915_GEM_DOMAIN_GTT))
		(void) i915_add_request(dev, flush_domains);

	return 0;
}

/** Unbinds all objects that are on the given buffer list. */
static int
i915_gem_evict_from_list(struct drm_device *dev, struct list_head *head)
{
	struct drm_gem_object *obj;
	struct drm_i915_gem_object *obj_priv;
	int ret;

	while (!list_empty(head)) {
		obj_priv = list_first_entry(head,
					    struct drm_i915_gem_object,
					    list);
		obj = obj_priv->obj;

		if (obj_priv->pin_count != 0) {
			DRM_ERROR("Pinned object in unbind list\n");
			mutex_unlock(&dev->struct_mutex);
			return -EINVAL;
		}

		ret = i915_gem_object_unbind(obj);
		if (ret != 0) {
			DRM_ERROR("Error unbinding object in LeaveVT: %d\n",
				  ret);
			mutex_unlock(&dev->struct_mutex);
			return ret;
		}
	}


	return 0;
}

static int
i915_gem_idle(struct drm_device *dev)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	uint32_t seqno, cur_seqno, last_seqno;
	int stuck, ret;

	mutex_lock(&dev->struct_mutex);

	if (dev_priv->mm.suspended || dev_priv->ring.ring_obj == NULL) {
		mutex_unlock(&dev->struct_mutex);
		return 0;
	}

	/* Hack!  Don't let anybody do execbuf while we don't control the chip.
	 * We need to replace this with a semaphore, or something.
	 */
	dev_priv->mm.suspended = 1;

	/* Cancel the retire work handler, wait for it to finish if running
	 */
	mutex_unlock(&dev->struct_mutex);
	cancel_delayed_work_sync(&dev_priv->mm.retire_work);
	mutex_lock(&dev->struct_mutex);

	i915_kernel_lost_context(dev);

	/* Flush the GPU along with all non-CPU write domains
	 */
	i915_gem_flush(dev, ~(I915_GEM_DOMAIN_CPU|I915_GEM_DOMAIN_GTT),
		       ~(I915_GEM_DOMAIN_CPU|I915_GEM_DOMAIN_GTT));
	seqno = i915_add_request(dev, ~(I915_GEM_DOMAIN_CPU |
					I915_GEM_DOMAIN_GTT));

	if (seqno == 0) {
		mutex_unlock(&dev->struct_mutex);
		return -ENOMEM;
	}

	dev_priv->mm.waiting_gem_seqno = seqno;
	last_seqno = 0;
	stuck = 0;
	for (;;) {
		cur_seqno = i915_get_gem_seqno(dev);
		if (i915_seqno_passed(cur_seqno, seqno))
			break;
		if (last_seqno == cur_seqno) {
			if (stuck++ > 100) {
				DRM_ERROR("hardware wedged\n");
				dev_priv->mm.wedged = 1;
				DRM_WAKEUP(&dev_priv->irq_queue);
				break;
			}
		}
		msleep(10);
		last_seqno = cur_seqno;
	}
	dev_priv->mm.waiting_gem_seqno = 0;

	i915_gem_retire_requests(dev);

	/* Active and flushing should now be empty as we've
	 * waited for a sequence higher than any pending execbuffer
	 */
	BUG_ON(!list_empty(&dev_priv->mm.active_list));
	BUG_ON(!list_empty(&dev_priv->mm.flushing_list));

	/* Request should now be empty as we've also waited
	 * for the last request in the list
	 */
	BUG_ON(!list_empty(&dev_priv->mm.request_list));

	/* Move all buffers out of the GTT. */
	ret = i915_gem_evict_from_list(dev, &dev_priv->mm.inactive_list);
	if (ret) {
		mutex_unlock(&dev->struct_mutex);
		return ret;
	}

	BUG_ON(!list_empty(&dev_priv->mm.active_list));
	BUG_ON(!list_empty(&dev_priv->mm.flushing_list));
	BUG_ON(!list_empty(&dev_priv->mm.inactive_list));
	BUG_ON(!list_empty(&dev_priv->mm.request_list));

	i915_gem_cleanup_ringbuffer(dev);
	mutex_unlock(&dev->struct_mutex);

	return 0;
}

static int
i915_gem_init_hws(struct drm_device *dev)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	struct drm_gem_object *obj;
	struct drm_i915_gem_object *obj_priv;
	int ret;

	/* If we need a physical address for the status page, it's already
	 * initialized at driver load time.
	 */
	if (!I915_NEED_GFX_HWS(dev))
		return 0;

	obj = drm_gem_object_alloc(dev, 4096);
	if (obj == NULL) {
		DRM_ERROR("Failed to allocate status page\n");
		return -ENOMEM;
	}
	obj_priv = obj->driver_private;
	obj_priv->agp_type = AGP_USER_CACHED_MEMORY;

	ret = i915_gem_object_pin(obj, 4096);
	if (ret != 0) {
		drm_gem_object_unreference(obj);
		return ret;
	}

	dev_priv->status_gfx_addr = obj_priv->gtt_offset;

	dev_priv->hw_status_page = kmap(obj_priv->page_list[0]);
	if (dev_priv->hw_status_page == NULL) {
		DRM_ERROR("Failed to map status page.\n");
		memset(&dev_priv->hws_map, 0, sizeof(dev_priv->hws_map));
		drm_gem_object_unreference(obj);
		return -EINVAL;
	}
	dev_priv->hws_obj = obj;
	memset(dev_priv->hw_status_page, 0, PAGE_SIZE);
	I915_WRITE(HWS_PGA, dev_priv->status_gfx_addr);
	I915_READ(HWS_PGA); /* posting read */
	DRM_DEBUG("hws offset: 0x%08x\n", dev_priv->status_gfx_addr);

	return 0;
}

static int
i915_gem_init_ringbuffer(struct drm_device *dev)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	struct drm_gem_object *obj;
	struct drm_i915_gem_object *obj_priv;
	int ret;
	u32 head;

	ret = i915_gem_init_hws(dev);
	if (ret != 0)
		return ret;

	obj = drm_gem_object_alloc(dev, 128 * 1024);
	if (obj == NULL) {
		DRM_ERROR("Failed to allocate ringbuffer\n");
		return -ENOMEM;
	}
	obj_priv = obj->driver_private;

	ret = i915_gem_object_pin(obj, 4096);
	if (ret != 0) {
		drm_gem_object_unreference(obj);
		return ret;
	}

	/* Set up the kernel mapping for the ring. */
	dev_priv->ring.Size = obj->size;
	dev_priv->ring.tail_mask = obj->size - 1;

	dev_priv->ring.map.offset = dev->agp->base + obj_priv->gtt_offset;
	dev_priv->ring.map.size = obj->size;
	dev_priv->ring.map.type = 0;
	dev_priv->ring.map.flags = 0;
	dev_priv->ring.map.mtrr = 0;

	drm_core_ioremap_wc(&dev_priv->ring.map, dev);
	if (dev_priv->ring.map.handle == NULL) {
		DRM_ERROR("Failed to map ringbuffer.\n");
		memset(&dev_priv->ring, 0, sizeof(dev_priv->ring));
		drm_gem_object_unreference(obj);
		return -EINVAL;
	}
	dev_priv->ring.ring_obj = obj;
	dev_priv->ring.virtual_start = dev_priv->ring.map.handle;

	/* Stop the ring if it's running. */
	I915_WRITE(PRB0_CTL, 0);
	I915_WRITE(PRB0_TAIL, 0);
	I915_WRITE(PRB0_HEAD, 0);

	/* Initialize the ring. */
	I915_WRITE(PRB0_START, obj_priv->gtt_offset);
	head = I915_READ(PRB0_HEAD) & HEAD_ADDR;

	/* G45 ring initialization fails to reset head to zero */
	if (head != 0) {
		DRM_ERROR("Ring head not reset to zero "
			  "ctl %08x head %08x tail %08x start %08x\n",
			  I915_READ(PRB0_CTL),
			  I915_READ(PRB0_HEAD),
			  I915_READ(PRB0_TAIL),
			  I915_READ(PRB0_START));
		I915_WRITE(PRB0_HEAD, 0);

		DRM_ERROR("Ring head forced to zero "
			  "ctl %08x head %08x tail %08x start %08x\n",
			  I915_READ(PRB0_CTL),
			  I915_READ(PRB0_HEAD),
			  I915_READ(PRB0_TAIL),
			  I915_READ(PRB0_START));
	}

	I915_WRITE(PRB0_CTL,
		   ((obj->size - 4096) & RING_NR_PAGES) |
		   RING_NO_REPORT |
		   RING_VALID);

	head = I915_READ(PRB0_HEAD) & HEAD_ADDR;

	/* If the head is still not zero, the ring is dead */
	if (head != 0) {
		DRM_ERROR("Ring initialization failed "
			  "ctl %08x head %08x tail %08x start %08x\n",
			  I915_READ(PRB0_CTL),
			  I915_READ(PRB0_HEAD),
			  I915_READ(PRB0_TAIL),
			  I915_READ(PRB0_START));
		return -EIO;
	}

	/* Update our cache of the ring state */
	i915_kernel_lost_context(dev);

	return 0;
}

static void
i915_gem_cleanup_ringbuffer(struct drm_device *dev)
{
	drm_i915_private_t *dev_priv = dev->dev_private;

	if (dev_priv->ring.ring_obj == NULL)
		return;

	drm_core_ioremapfree(&dev_priv->ring.map, dev);

	i915_gem_object_unpin(dev_priv->ring.ring_obj);
	drm_gem_object_unreference(dev_priv->ring.ring_obj);
	dev_priv->ring.ring_obj = NULL;
	memset(&dev_priv->ring, 0, sizeof(dev_priv->ring));

	if (dev_priv->hws_obj != NULL) {
		struct drm_gem_object *obj = dev_priv->hws_obj;
		struct drm_i915_gem_object *obj_priv = obj->driver_private;

		kunmap(obj_priv->page_list[0]);
		i915_gem_object_unpin(obj);
		drm_gem_object_unreference(obj);
		dev_priv->hws_obj = NULL;
		memset(&dev_priv->hws_map, 0, sizeof(dev_priv->hws_map));
		dev_priv->hw_status_page = NULL;

		/* Write high address into HWS_PGA when disabling. */
		I915_WRITE(HWS_PGA, 0x1ffff000);
	}
}

int
i915_gem_entervt_ioctl(struct drm_device *dev, void *data,
		       struct drm_file *file_priv)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	int ret;

	if (dev_priv->mm.wedged) {
		DRM_ERROR("Reenabling wedged hardware, good luck\n");
		dev_priv->mm.wedged = 0;
	}

	ret = i915_gem_init_ringbuffer(dev);
	if (ret != 0)
		return ret;

	dev_priv->mm.gtt_mapping = io_mapping_create_wc(dev->agp->base,
							dev->agp->agp_info.aper_size
							* 1024 * 1024);

	mutex_lock(&dev->struct_mutex);
	BUG_ON(!list_empty(&dev_priv->mm.active_list));
	BUG_ON(!list_empty(&dev_priv->mm.flushing_list));
	BUG_ON(!list_empty(&dev_priv->mm.inactive_list));
	BUG_ON(!list_empty(&dev_priv->mm.request_list));
	dev_priv->mm.suspended = 0;
	mutex_unlock(&dev->struct_mutex);

	drm_irq_install(dev);

	return 0;
}

int
i915_gem_leavevt_ioctl(struct drm_device *dev, void *data,
		       struct drm_file *file_priv)
{
	drm_i915_private_t *dev_priv = dev->dev_private;
	int ret;

	ret = i915_gem_idle(dev);
	drm_irq_uninstall(dev);

	io_mapping_free(dev_priv->mm.gtt_mapping);
	return ret;
}

void
i915_gem_lastclose(struct drm_device *dev)
{
	int ret;

	ret = i915_gem_idle(dev);
	if (ret)
		DRM_ERROR("failed to idle hardware: %d\n", ret);
}

void
i915_gem_load(struct drm_device *dev)
{
	drm_i915_private_t *dev_priv = dev->dev_private;

	INIT_LIST_HEAD(&dev_priv->mm.active_list);
	INIT_LIST_HEAD(&dev_priv->mm.flushing_list);
	INIT_LIST_HEAD(&dev_priv->mm.inactive_list);
	INIT_LIST_HEAD(&dev_priv->mm.request_list);
	INIT_DELAYED_WORK(&dev_priv->mm.retire_work,
			  i915_gem_retire_work_handler);
	dev_priv->mm.next_gem_seqno = 1;

	i915_gem_detect_bit_6_swizzle(dev);
}