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authorIngo Molnar <mingo@elte.hu>2009-02-07 12:31:54 -0500
committerIngo Molnar <mingo@elte.hu>2009-02-07 12:31:54 -0500
commit673f8205914a12e928c65afbcd78ae748f78df53 (patch)
tree38c60215646d079fab3bff812e094e914960c7ec /kernel/dma-coherent.c
parentcf47b8f3d96b0b8b10b557444a28b3ca4024ff82 (diff)
parentae1a25da8448271a99745da03100d5299575a269 (diff)
Merge branch 'linus' into core/locking
Conflicts: fs/btrfs/locking.c
Diffstat (limited to 'kernel/dma-coherent.c')
-rw-r--r--kernel/dma-coherent.c47
1 files changed, 24 insertions, 23 deletions
diff --git a/kernel/dma-coherent.c b/kernel/dma-coherent.c
index 038707404b76..962a3b574f21 100644
--- a/kernel/dma-coherent.c
+++ b/kernel/dma-coherent.c
@@ -98,7 +98,7 @@ EXPORT_SYMBOL(dma_mark_declared_memory_occupied);
98 * @size: size of requested memory area 98 * @size: size of requested memory area
99 * @dma_handle: This will be filled with the correct dma handle 99 * @dma_handle: This will be filled with the correct dma handle
100 * @ret: This pointer will be filled with the virtual address 100 * @ret: This pointer will be filled with the virtual address
101 * to allocated area. 101 * to allocated area.
102 * 102 *
103 * This function should be only called from per-arch dma_alloc_coherent() 103 * This function should be only called from per-arch dma_alloc_coherent()
104 * to support allocation from per-device coherent memory pools. 104 * to support allocation from per-device coherent memory pools.
@@ -118,31 +118,32 @@ int dma_alloc_from_coherent(struct device *dev, ssize_t size,
118 mem = dev->dma_mem; 118 mem = dev->dma_mem;
119 if (!mem) 119 if (!mem)
120 return 0; 120 return 0;
121 if (unlikely(size > mem->size)) 121
122 return 0; 122 *ret = NULL;
123
124 if (unlikely(size > (mem->size << PAGE_SHIFT)))
125 goto err;
123 126
124 pageno = bitmap_find_free_region(mem->bitmap, mem->size, order); 127 pageno = bitmap_find_free_region(mem->bitmap, mem->size, order);
125 if (pageno >= 0) { 128 if (unlikely(pageno < 0))
126 /* 129 goto err;
127 * Memory was found in the per-device arena. 130
128 */ 131 /*
129 *dma_handle = mem->device_base + (pageno << PAGE_SHIFT); 132 * Memory was found in the per-device area.
130 *ret = mem->virt_base + (pageno << PAGE_SHIFT); 133 */
131 memset(*ret, 0, size); 134 *dma_handle = mem->device_base + (pageno << PAGE_SHIFT);
132 } else if (mem->flags & DMA_MEMORY_EXCLUSIVE) { 135 *ret = mem->virt_base + (pageno << PAGE_SHIFT);
133 /* 136 memset(*ret, 0, size);
134 * The per-device arena is exhausted and we are not 137
135 * permitted to fall back to generic memory.
136 */
137 *ret = NULL;
138 } else {
139 /*
140 * The per-device arena is exhausted and we are
141 * permitted to fall back to generic memory.
142 */
143 return 0;
144 }
145 return 1; 138 return 1;
139
140err:
141 /*
142 * In the case where the allocation can not be satisfied from the
143 * per-device area, try to fall back to generic memory if the
144 * constraints allow it.
145 */
146 return mem->flags & DMA_MEMORY_EXCLUSIVE;
146} 147}
147EXPORT_SYMBOL(dma_alloc_from_coherent); 148EXPORT_SYMBOL(dma_alloc_from_coherent);
148 149