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authorKeith Whitwell <keith@tungstengraphics.com>2004-06-10 12:45:38 +0000
committerKeith Whitwell <keith@tungstengraphics.com>2004-06-10 12:45:38 +0000
commit291ffeae9a2b95cf35835ddd0f25e434e4c26f44 (patch)
tree5f68361aa055c8632a75cfbc5350acb067efd797 /shared/i915_mem.c
parent78d0fd6526bb725151d8dce86006af7616ee4758 (diff)
i915.o drm driver
Diffstat (limited to 'shared/i915_mem.c')
-rw-r--r--shared/i915_mem.c361
1 files changed, 361 insertions, 0 deletions
diff --git a/shared/i915_mem.c b/shared/i915_mem.c
new file mode 100644
index 00000000..58f7b888
--- /dev/null
+++ b/shared/i915_mem.c
@@ -0,0 +1,361 @@
+/* i915_mem.c -- Simple agp/fb memory manager for i915 -*- linux-c -*-
+ */
+/**************************************************************************
+ *
+ * Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.
+ * All Rights Reserved.
+ *
+ **************************************************************************/
+
+#include "i915.h"
+#include "drmP.h"
+#include "drm.h"
+#include "i915_drm.h"
+#include "i915_drv.h"
+
+/* This memory manager is integrated into the global/local lru
+ * mechanisms used by the clients. Specifically, it operates by
+ * setting the 'in_use' fields of the global LRU to indicate whether
+ * this region is privately allocated to a client.
+ *
+ * This does require the client to actually respect that field.
+ *
+ * Currently no effort is made to allocate 'private' memory in any
+ * clever way - the LRU information isn't used to determine which
+ * block to allocate, and the ring is drained prior to allocations --
+ * in other words allocation is expensive.
+ */
+static void mark_block( drm_device_t *dev, struct mem_block *p,
+ int in_use )
+{
+ drm_i915_private_t *dev_priv = dev->dev_private;
+ drm_i915_sarea_t *sarea_priv = dev_priv->sarea_priv;
+ drm_tex_region_t *list;
+ unsigned shift, nr;
+ unsigned start;
+ unsigned end;
+ unsigned i;
+ int age;
+
+ shift = dev_priv->tex_lru_log_granularity;
+ nr = I915_NR_TEX_REGIONS;
+
+ start = p->start >> shift;
+ end = (p->start + p->size - 1) >> shift;
+
+ age = ++sarea_priv->texAge;
+ list = sarea_priv->texList;
+
+ /* Mark the regions with the new flag and update their age. Move
+ * them to head of list to preserve LRU semantics.
+ */
+ for (i = start ; i <= end ; i++) {
+ list[i].in_use = in_use;
+ list[i].age = age;
+
+ /* remove_from_list(i)
+ */
+ list[(unsigned)list[i].next].prev = list[i].prev;
+ list[(unsigned)list[i].prev].next = list[i].next;
+
+ /* insert_at_head(list, i)
+ */
+ list[i].prev = nr;
+ list[i].next = list[nr].next;
+ list[(unsigned)list[nr].next].prev = i;
+ list[nr].next = i;
+ }
+}
+
+
+/* Very simple allocator for agp memory, working on a static range
+ * already mapped into each client's address space.
+ */
+
+static struct mem_block *split_block(struct mem_block *p, int start, int size,
+ DRMFILE filp )
+{
+ /* Maybe cut off the start of an existing block */
+ if (start > p->start) {
+ struct mem_block *newblock = DRM_MALLOC(sizeof(*newblock));
+ if (!newblock)
+ goto out;
+ newblock->start = start;
+ newblock->size = p->size - (start - p->start);
+ newblock->filp = 0;
+ newblock->next = p->next;
+ newblock->prev = p;
+ p->next->prev = newblock;
+ p->next = newblock;
+ p->size -= newblock->size;
+ p = newblock;
+ }
+
+ /* Maybe cut off the end of an existing block */
+ if (size < p->size) {
+ struct mem_block *newblock = DRM_MALLOC(sizeof(*newblock));
+ if (!newblock)
+ goto out;
+ newblock->start = start + size;
+ newblock->size = p->size - size;
+ newblock->filp = 0;
+ newblock->next = p->next;
+ newblock->prev = p;
+ p->next->prev = newblock;
+ p->next = newblock;
+ p->size = size;
+ }
+
+ out:
+ /* Our block is in the middle */
+ p->filp = filp;
+ return p;
+}
+
+static struct mem_block *alloc_block( struct mem_block *heap, int size,
+ int align2, DRMFILE filp )
+{
+ struct mem_block *p;
+ int mask = (1 << align2)-1;
+
+ for (p = heap->next ; p != heap ; p = p->next) {
+ int start = (p->start + mask) & ~mask;
+ if (p->filp == 0 && start + size <= p->start + p->size)
+ return split_block( p, start, size, filp );
+ }
+
+ return NULL;
+}
+
+static struct mem_block *find_block( struct mem_block *heap, int start )
+{
+ struct mem_block *p;
+
+ for (p = heap->next ; p != heap ; p = p->next)
+ if (p->start == start)
+ return p;
+
+ return NULL;
+}
+
+
+static void free_block( struct mem_block *p )
+{
+ p->filp = 0;
+
+ /* Assumes a single contiguous range. Needs a special filp in
+ * 'heap' to stop it being subsumed.
+ */
+ if (p->next->filp == 0) {
+ struct mem_block *q = p->next;
+ p->size += q->size;
+ p->next = q->next;
+ p->next->prev = p;
+ DRM_FREE(q, sizeof(*q));
+ }
+
+ if (p->prev->filp == 0) {
+ struct mem_block *q = p->prev;
+ q->size += p->size;
+ q->next = p->next;
+ q->next->prev = q;
+ DRM_FREE(p, sizeof(*q));
+ }
+}
+
+/* Initialize. How to check for an uninitialized heap?
+ */
+static int init_heap(struct mem_block **heap, int start, int size)
+{
+ struct mem_block *blocks = DRM_MALLOC(sizeof(*blocks));
+
+ if (!blocks)
+ return -ENOMEM;
+
+ *heap = DRM_MALLOC(sizeof(**heap));
+ if (!*heap) {
+ DRM_FREE( blocks, sizeof(*blocks) );
+ return -ENOMEM;
+ }
+
+ blocks->start = start;
+ blocks->size = size;
+ blocks->filp = 0;
+ blocks->next = blocks->prev = *heap;
+
+ memset( *heap, 0, sizeof(**heap) );
+ (*heap)->filp = (DRMFILE) -1;
+ (*heap)->next = (*heap)->prev = blocks;
+ return 0;
+}
+
+
+/* Free all blocks associated with the releasing file.
+ */
+void i915_mem_release( drm_device_t *dev,
+ DRMFILE filp, struct mem_block *heap )
+{
+ struct mem_block *p;
+
+ if (!heap || !heap->next)
+ return;
+
+ for (p = heap->next ; p != heap ; p = p->next) {
+ if (p->filp == filp) {
+ p->filp = 0;
+ mark_block( dev, p, 0 );
+ }
+ }
+
+ /* Assumes a single contiguous range. Needs a special filp in
+ * 'heap' to stop it being subsumed.
+ */
+ for (p = heap->next ; p != heap ; p = p->next) {
+ while (p->filp == 0 && p->next->filp == 0) {
+ struct mem_block *q = p->next;
+ p->size += q->size;
+ p->next = q->next;
+ p->next->prev = p;
+ DRM_FREE(q, sizeof(*q));
+ }
+ }
+}
+
+/* Shutdown.
+ */
+void i915_mem_takedown( struct mem_block **heap )
+{
+ struct mem_block *p;
+
+ if (!*heap)
+ return;
+
+ for (p = (*heap)->next ; p != *heap ; ) {
+ struct mem_block *q = p;
+ p = p->next;
+ DRM_FREE(q, sizeof(*q));
+ }
+
+ DRM_FREE( *heap, sizeof(**heap) );
+ *heap = 0;
+}
+
+
+
+static struct mem_block **get_heap( drm_i915_private_t *dev_priv,
+ int region )
+{
+ switch( region ) {
+ case I915_MEM_REGION_AGP:
+ return &dev_priv->agp_heap;
+ default:
+ return 0;
+ }
+}
+
+
+/* IOCTL HANDLERS */
+
+int i915_mem_alloc( DRM_IOCTL_ARGS )
+{
+ DRM_DEVICE;
+ drm_i915_private_t *dev_priv = dev->dev_private;
+ drm_i915_mem_alloc_t alloc;
+ struct mem_block *block, **heap;
+
+ if ( !dev_priv ) {
+ DRM_ERROR( "%s called with no initialization\n", __FUNCTION__ );
+ return DRM_ERR(EINVAL);
+ }
+
+ DRM_COPY_FROM_USER_IOCTL( alloc, (drm_i915_mem_alloc_t *)data,
+ sizeof(alloc) );
+
+ heap = get_heap( dev_priv, alloc.region );
+ if (!heap || !*heap)
+ return DRM_ERR(EFAULT);
+
+ /* Make things easier on ourselves: all allocations at least
+ * 4k aligned.
+ */
+ if (alloc.alignment < 12)
+ alloc.alignment = 12;
+
+ block = alloc_block( *heap, alloc.size, alloc.alignment,
+ filp );
+
+ if (!block)
+ return DRM_ERR(ENOMEM);
+
+ mark_block( dev, block, 1 );
+
+ if ( DRM_COPY_TO_USER( alloc.region_offset, &block->start,
+ sizeof(int) ) ) {
+ DRM_ERROR( "copy_to_user\n" );
+ return DRM_ERR(EFAULT);
+ }
+
+ return 0;
+}
+
+
+
+int i915_mem_free( DRM_IOCTL_ARGS )
+{
+ DRM_DEVICE;
+ drm_i915_private_t *dev_priv = dev->dev_private;
+ drm_i915_mem_free_t memfree;
+ struct mem_block *block, **heap;
+
+ if ( !dev_priv ) {
+ DRM_ERROR( "%s called with no initialization\n", __FUNCTION__ );
+ return DRM_ERR(EINVAL);
+ }
+
+ DRM_COPY_FROM_USER_IOCTL( memfree, (drm_i915_mem_free_t *)data,
+ sizeof(memfree) );
+
+ heap = get_heap( dev_priv, memfree.region );
+ if (!heap || !*heap)
+ return DRM_ERR(EFAULT);
+
+ block = find_block( *heap, memfree.region_offset );
+ if (!block)
+ return DRM_ERR(EFAULT);
+
+ if (block->filp != filp)
+ return DRM_ERR(EPERM);
+
+ mark_block( dev, block, 0 );
+ free_block( block );
+ return 0;
+}
+
+int i915_mem_init_heap( DRM_IOCTL_ARGS )
+{
+ DRM_DEVICE;
+ drm_i915_private_t *dev_priv = dev->dev_private;
+ drm_i915_mem_init_heap_t initheap;
+ struct mem_block **heap;
+
+ if ( !dev_priv ) {
+ DRM_ERROR( "%s called with no initialization\n", __FUNCTION__ );
+ return DRM_ERR(EINVAL);
+ }
+
+ DRM_COPY_FROM_USER_IOCTL( initheap, (drm_i915_mem_init_heap_t *)data,
+ sizeof(initheap) );
+
+ heap = get_heap( dev_priv, initheap.region );
+ if (!heap)
+ return DRM_ERR(EFAULT);
+
+ if (*heap) {
+ DRM_ERROR("heap already initialized?");
+ return DRM_ERR(EFAULT);
+ }
+
+ return init_heap( heap, initheap.start, initheap.size );
+}
+
+