[PATCH] drm: mm: fix range restricted allocations
With the code cleanup in
7a6b2896f261894dde287d3faefa4b432cddca53 is the first bad commit
commit 7a6b2896f261894dde287d3faefa4b432cddca53
Author: Daniel Vetter
Date: Fri Jul 2 15:02:15 2010 +0100
drm_mm: extract check_free_mm_node
I've botched up the range-restriction checks. The result is usually
an X server dying with SIGBUS in libpixman (software fallback rendering).
Change the code to adjust the start and end for range restricted
allocations. IMHO this even makes the code a bit clearer.
Signed-off-by: Daniel Vetter
---
drivers/gpu/drm/drm_mm.c | 24 ++--
1 files changed, 14 insertions(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c
index da99edc..a6bfc30 100644
--- a/drivers/gpu/drm/drm_mm.c
+++ b/drivers/gpu/drm/drm_mm.c
@@ -285,21 +285,21 @@ void drm_mm_put_block(struct drm_mm_node *cur)
EXPORT_SYMBOL(drm_mm_put_block);
-static int check_free_mm_node(struct drm_mm_node *entry, unsigned long size,
- unsigned alignment)
+static int check_free_hole(unsigned long start, unsigned long end,
+ unsigned long size, unsigned alignment)
{
unsigned wasted = 0;
- if (entry->size < size)
+ if (end - start < size)
return 0;
if (alignment) {
- register unsigned tmp = entry->start % alignment;
+ unsigned tmp = start % alignment;
if (tmp)
wasted = alignment - tmp;
}
- if (entry->size >= size + wasted) {
+ if (end >= start + size + wasted) {
return 1;
}
@@ -320,7 +320,8 @@ struct drm_mm_node *drm_mm_search_free(const struct drm_mm
*mm,
best_size = ~0UL;
list_for_each_entry(entry, >free_stack, free_stack) {
- if (!check_free_mm_node(entry, size, alignment))
+ if (!check_free_hole(entry->start, entry->start + entry->size,
+size, alignment))
continue;
if (!best_match)
@@ -353,10 +354,12 @@ struct drm_mm_node *drm_mm_search_free_in_range(const
struct drm_mm *mm,
best_size = ~0UL;
list_for_each_entry(entry, >free_stack, free_stack) {
- if (entry->start > end || (entry->start+entry->size) < start)
- continue;
+ unsigned long adj_start = entry->start < start ?
+ start : entry->start;
+ unsigned long adj_end = entry->start + entry->size > end ?
+ end : entry->start + entry->size;
- if (!check_free_mm_node(entry, size, alignment))
+ if (!check_free_hole(adj_start, adj_end, size, alignment))
continue;
if (!best_match)
@@ -449,7 +452,8 @@ int drm_mm_scan_add_block(struct drm_mm_node *node)
node->free_stack.prev = prev_free;
node->free_stack.next = next_free;
- if (check_free_mm_node(node, mm->scan_size, mm->scan_alignment)) {
+ if (check_free_hole(node->start, node->start + node->size,
+ mm->scan_size, mm->scan_alignment)) {
mm->scan_hit_start = node->start;
mm->scan_hit_size = node->size;
--
1.7.1
[PATCH] drm: mm: fix range restricted allocations
With the code cleanup in
7a6b2896f261894dde287d3faefa4b432cddca53 is the first bad commit
commit 7a6b2896f261894dde287d3faefa4b432cddca53
Author: Daniel Vetter daniel.vet...@ffwll.ch
Date: Fri Jul 2 15:02:15 2010 +0100
drm_mm: extract check_free_mm_node
I've botched up the range-restriction checks. The result is usually
an X server dying with SIGBUS in libpixman (software fallback rendering).
Change the code to adjust the start and end for range restricted
allocations. IMHO this even makes the code a bit clearer.
Signed-off-by: Daniel Vetter daniel.vet...@ffwll.ch
---
drivers/gpu/drm/drm_mm.c | 24 ++--
1 files changed, 14 insertions(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c
index da99edc..a6bfc30 100644
--- a/drivers/gpu/drm/drm_mm.c
+++ b/drivers/gpu/drm/drm_mm.c
@@ -285,21 +285,21 @@ void drm_mm_put_block(struct drm_mm_node *cur)
EXPORT_SYMBOL(drm_mm_put_block);
-static int check_free_mm_node(struct drm_mm_node *entry, unsigned long size,
- unsigned alignment)
+static int check_free_hole(unsigned long start, unsigned long end,
+ unsigned long size, unsigned alignment)
{
unsigned wasted = 0;
- if (entry-size size)
+ if (end - start size)
return 0;
if (alignment) {
- register unsigned tmp = entry-start % alignment;
+ unsigned tmp = start % alignment;
if (tmp)
wasted = alignment - tmp;
}
- if (entry-size = size + wasted) {
+ if (end = start + size + wasted) {
return 1;
}
@@ -320,7 +320,8 @@ struct drm_mm_node *drm_mm_search_free(const struct drm_mm
*mm,
best_size = ~0UL;
list_for_each_entry(entry, mm-free_stack, free_stack) {
- if (!check_free_mm_node(entry, size, alignment))
+ if (!check_free_hole(entry-start, entry-start + entry-size,
+size, alignment))
continue;
if (!best_match)
@@ -353,10 +354,12 @@ struct drm_mm_node *drm_mm_search_free_in_range(const
struct drm_mm *mm,
best_size = ~0UL;
list_for_each_entry(entry, mm-free_stack, free_stack) {
- if (entry-start end || (entry-start+entry-size) start)
- continue;
+ unsigned long adj_start = entry-start start ?
+ start : entry-start;
+ unsigned long adj_end = entry-start + entry-size end ?
+ end : entry-start + entry-size;
- if (!check_free_mm_node(entry, size, alignment))
+ if (!check_free_hole(adj_start, adj_end, size, alignment))
continue;
if (!best_match)
@@ -449,7 +452,8 @@ int drm_mm_scan_add_block(struct drm_mm_node *node)
node-free_stack.prev = prev_free;
node-free_stack.next = next_free;
- if (check_free_mm_node(node, mm-scan_size, mm-scan_alignment)) {
+ if (check_free_hole(node-start, node-start + node-size,
+ mm-scan_size, mm-scan_alignment)) {
mm-scan_hit_start = node-start;
mm-scan_hit_size = node-size;
--
1.7.1
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