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-rw-r--r--mesalib/src/gallium/auxiliary/util/u_suballoc.c132
1 files changed, 132 insertions, 0 deletions
diff --git a/mesalib/src/gallium/auxiliary/util/u_suballoc.c b/mesalib/src/gallium/auxiliary/util/u_suballoc.c
new file mode 100644
index 000000000..efa9a0c5e
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+++ b/mesalib/src/gallium/auxiliary/util/u_suballoc.c
@@ -0,0 +1,132 @@
+/**************************************************************************
+ *
+ * Copyright 2009 VMware, Inc.
+ * Copyright 2012 Marek Olšák <maraeo@gmail.com>
+ * All Rights Reserved.
+ *
+ * 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, sub license, 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 NON-INFRINGEMENT.
+ * IN NO EVENT SHALL THE AUTHORS AND/OR ITS SUPPLIERS 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.
+ *
+ **************************************************************************/
+
+/* A simple allocator that suballocates memory from a large buffer. */
+
+#include "pipe/p_defines.h"
+#include "util/u_inlines.h"
+#include "pipe/p_context.h"
+#include "util/u_memory.h"
+#include "util/u_math.h"
+
+#include "u_suballoc.h"
+
+
+struct u_suballocator {
+ struct pipe_context *pipe;
+
+ unsigned size; /* Size of the whole buffer, in bytes. */
+ unsigned alignment; /* Alignment of each sub-allocation. */
+ unsigned bind; /* Bitmask of PIPE_BIND_* flags. */
+ unsigned usage; /* One of PIPE_USAGE_* flags. */
+ boolean zero_buffer_memory; /* If the buffer contents should be zeroed. */
+
+ struct pipe_resource *buffer; /* The buffer we suballocate from. */
+ unsigned offset; /* Aligned offset pointing at the first unused byte. */
+};
+
+
+/**
+ * Create a suballocator.
+ *
+ * \p zero_buffer_memory determines whether the buffer contents should be
+ * cleared to 0 after the allocation.
+ */
+struct u_suballocator *
+u_suballocator_create(struct pipe_context *pipe, unsigned size,
+ unsigned alignment, unsigned bind, unsigned usage,
+ boolean zero_buffer_memory)
+{
+ struct u_suballocator *allocator = CALLOC_STRUCT(u_suballocator);
+ if (!allocator)
+ return NULL;
+
+ allocator->pipe = pipe;
+ allocator->size = align(size, alignment);
+ allocator->alignment = alignment;
+ allocator->bind = bind;
+ allocator->usage = usage;
+ allocator->zero_buffer_memory = zero_buffer_memory;
+ return allocator;
+}
+
+void
+u_suballocator_destroy(struct u_suballocator *allocator)
+{
+ pipe_resource_reference(&allocator->buffer, NULL);
+ FREE(allocator);
+}
+
+void
+u_suballocator_alloc(struct u_suballocator *allocator, unsigned size,
+ unsigned *out_offset, struct pipe_resource **outbuf)
+{
+ unsigned alloc_size = align(size, allocator->alignment);
+
+ /* Don't allow allocations larger than the buffer size. */
+ if (alloc_size > allocator->size)
+ goto fail;
+
+ /* Make sure we have enough space in the buffer. */
+ if (!allocator->buffer ||
+ allocator->offset + alloc_size > allocator->size) {
+ /* Allocate a new buffer. */
+ pipe_resource_reference(&allocator->buffer, NULL);
+ allocator->offset = 0;
+ allocator->buffer =
+ pipe_buffer_create(allocator->pipe->screen, allocator->bind,
+ allocator->usage, allocator->size);
+ if (!allocator->buffer)
+ goto fail;
+
+ /* Clear the memory if needed. */
+ if (allocator->zero_buffer_memory) {
+ struct pipe_transfer *transfer = NULL;
+ void *ptr;
+
+ ptr = pipe_buffer_map(allocator->pipe, allocator->buffer,
+ PIPE_TRANSFER_WRITE, &transfer);
+ memset(ptr, 0, allocator->size);
+ pipe_buffer_unmap(allocator->pipe, transfer);
+ }
+ }
+
+ assert(allocator->offset % allocator->alignment == 0);
+ assert(allocator->offset < allocator->buffer->width0);
+ assert(allocator->offset + alloc_size <= allocator->buffer->width0);
+
+ /* Return the buffer. */
+ *out_offset = allocator->offset;
+ pipe_resource_reference(outbuf, allocator->buffer);
+
+ allocator->offset += alloc_size;
+ return;
+
+fail:
+ pipe_resource_reference(outbuf, NULL);
+}