drm/radeon/kms: don't require up to 64k allocations. (v2)

This avoids needing to do a kmalloc > PAGE_SIZE for the main
indirect buffer chunk, it adds an accessor for all reads from
the chunk and caches a single page at a time for subsequent
reads.

changes since v1:
Use a two page pool which should be the most common case
a single packet spanning > PAGE_SIZE will be hit, but I'm
having trouble seeing anywhere we currently generate anything like that.
hopefully proper short page copying at end
added parser_error flag to set deep errors instead of having to test
every ib value fetch.
fixed bug in patch that went to list.

Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 36 insertions, 1 deletions

diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index d5de53e..7e34e43 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -342,7 +342,7 @@ struct radeon_ib {
 	unsigned long		idx;
 	uint64_t		gpu_addr;
 	struct radeon_fence	*fence;
-	volatile uint32_t	*ptr;
+	uint32_t	*ptr;
 	uint32_t		length_dw;
 };
 
@@ -415,7 +415,12 @@ struct radeon_cs_reloc {
 struct radeon_cs_chunk {
 	uint32_t		chunk_id;
 	uint32_t		length_dw;
+	int kpage_idx[2];
+	uint32_t                *kpage[2];
 	uint32_t		*kdata;
+	void __user *user_ptr;
+	int last_copied_page;
+	int last_page_index;
 };
 
 struct radeon_cs_parser {
@@ -438,8 +443,38 @@ struct radeon_cs_parser {
 	struct radeon_ib	*ib;
 	void			*track;
 	unsigned		family;
+	int parser_error;
 };
 
+extern int radeon_cs_update_pages(struct radeon_cs_parser *p, int pg_idx);
+extern int radeon_cs_finish_pages(struct radeon_cs_parser *p);
+
+
+static inline u32 radeon_get_ib_value(struct radeon_cs_parser *p, int idx)
+{
+	struct radeon_cs_chunk *ibc = &p->chunks[p->chunk_ib_idx];
+	u32 pg_idx, pg_offset;
+	u32 idx_value = 0;
+	int new_page;
+
+	pg_idx = (idx * 4) / PAGE_SIZE;
+	pg_offset = (idx * 4) % PAGE_SIZE;
+
+	if (ibc->kpage_idx[0] == pg_idx)
+		return ibc->kpage[0][pg_offset/4];
+	if (ibc->kpage_idx[1] == pg_idx)
+		return ibc->kpage[1][pg_offset/4];
+
+	new_page = radeon_cs_update_pages(p, pg_idx);
+	if (new_page < 0) {
+		p->parser_error = new_page;
+		return 0;
+	}
+
+	idx_value = ibc->kpage[new_page][pg_offset/4];
+	return idx_value;
+}
+
 struct radeon_cs_packet {
 	unsigned	idx;
 	unsigned	type;