drm/xen-front: Use Xen common shared buffer implementation

Use page directory based shared buffer implementation
now available as common code for Xen frontend drivers.

Remove flushing of shared buffer on page flip as this
workaround needs a proper fix.

Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>

1 files changed, 25 insertions, 40 deletions

diff --git a/drivers/gpu/drm/xen/xen_drm_front.c b/drivers/gpu/drm/xen/xen_drm_front.c
index 6b6d5ab82ec3..4d3d36fc3a5d 100644
--- a/drivers/gpu/drm/xen/xen_drm_front.c
+++ b/drivers/gpu/drm/xen/xen_drm_front.c
@@ -19,6 +19,7 @@
 #include <xen/xen.h>
 #include <xen/xenbus.h>
 
+#include <xen/xen-front-pgdir-shbuf.h>
 #include <xen/interface/io/displif.h>
 
 #include "xen_drm_front.h"
@@ -26,28 +27,20 @@
 #include "xen_drm_front_evtchnl.h"
 #include "xen_drm_front_gem.h"
 #include "xen_drm_front_kms.h"
-#include "xen_drm_front_shbuf.h"
 
 struct xen_drm_front_dbuf {
 	struct list_head list;
 	u64 dbuf_cookie;
 	u64 fb_cookie;
-	struct xen_drm_front_shbuf *shbuf;
+
+	struct xen_front_pgdir_shbuf shbuf;
 };
 
-static int dbuf_add_to_list(struct xen_drm_front_info *front_info,
-			    struct xen_drm_front_shbuf *shbuf, u64 dbuf_cookie)
+static void dbuf_add_to_list(struct xen_drm_front_info *front_info,
+			     struct xen_drm_front_dbuf *dbuf, u64 dbuf_cookie)
 {
-	struct xen_drm_front_dbuf *dbuf;
-
-	dbuf = kzalloc(sizeof(*dbuf), GFP_KERNEL);
-	if (!dbuf)
-		return -ENOMEM;
-
 	dbuf->dbuf_cookie = dbuf_cookie;
-	dbuf->shbuf = shbuf;
 	list_add(&dbuf->list, &front_info->dbuf_list);
-	return 0;
 }
 
 static struct xen_drm_front_dbuf *dbuf_get(struct list_head *dbuf_list,
@@ -62,15 +55,6 @@ static struct xen_drm_front_dbuf *dbuf_get(struct list_head *dbuf_list,
 	return NULL;
 }
 
-static void dbuf_flush_fb(struct list_head *dbuf_list, u64 fb_cookie)
-{
-	struct xen_drm_front_dbuf *buf, *q;
-
-	list_for_each_entry_safe(buf, q, dbuf_list, list)
-		if (buf->fb_cookie == fb_cookie)
-			xen_drm_front_shbuf_flush(buf->shbuf);
-}
-
 static void dbuf_free(struct list_head *dbuf_list, u64 dbuf_cookie)
 {
 	struct xen_drm_front_dbuf *buf, *q;
@@ -78,8 +62,8 @@ static void dbuf_free(struct list_head *dbuf_list, u64 dbuf_cookie)
 	list_for_each_entry_safe(buf, q, dbuf_list, list)
 		if (buf->dbuf_cookie == dbuf_cookie) {
 			list_del(&buf->list);
-			xen_drm_front_shbuf_unmap(buf->shbuf);
-			xen_drm_front_shbuf_free(buf->shbuf);
+			xen_front_pgdir_shbuf_unmap(&buf->shbuf);
+			xen_front_pgdir_shbuf_free(&buf->shbuf);
 			kfree(buf);
 			break;
 		}
@@ -91,8 +75,8 @@ static void dbuf_free_all(struct list_head *dbuf_list)
 
 	list_for_each_entry_safe(buf, q, dbuf_list, list) {
 		list_del(&buf->list);
-		xen_drm_front_shbuf_unmap(buf->shbuf);
-		xen_drm_front_shbuf_free(buf->shbuf);
+		xen_front_pgdir_shbuf_unmap(&buf->shbuf);
+		xen_front_pgdir_shbuf_free(&buf->shbuf);
 		kfree(buf);
 	}
 }
@@ -171,9 +155,9 @@ int xen_drm_front_dbuf_create(struct xen_drm_front_info *front_info,
 			      u32 bpp, u64 size, struct page **pages)
 {
 	struct xen_drm_front_evtchnl *evtchnl;
-	struct xen_drm_front_shbuf *shbuf;
+	struct xen_drm_front_dbuf *dbuf;
 	struct xendispl_req *req;
-	struct xen_drm_front_shbuf_cfg buf_cfg;
+	struct xen_front_pgdir_shbuf_cfg buf_cfg;
 	unsigned long flags;
 	int ret;
 
@@ -181,28 +165,29 @@ int xen_drm_front_dbuf_create(struct xen_drm_front_info *front_info,
 	if (unlikely(!evtchnl))
 		return -EIO;
 
+	dbuf = kzalloc(sizeof(*dbuf), GFP_KERNEL);
+	if (!dbuf)
+		return -ENOMEM;
+
+	dbuf_add_to_list(front_info, dbuf, dbuf_cookie);
+
 	memset(&buf_cfg, 0, sizeof(buf_cfg));
 	buf_cfg.xb_dev = front_info->xb_dev;
+	buf_cfg.num_pages = DIV_ROUND_UP(size, PAGE_SIZE);
 	buf_cfg.pages = pages;
-	buf_cfg.size = size;
+	buf_cfg.pgdir = &dbuf->shbuf;
 	buf_cfg.be_alloc = front_info->cfg.be_alloc;
 
-	shbuf = xen_drm_front_shbuf_alloc(&buf_cfg);
-	if (IS_ERR(shbuf))
-		return PTR_ERR(shbuf);
-
-	ret = dbuf_add_to_list(front_info, shbuf, dbuf_cookie);
-	if (ret < 0) {
-		xen_drm_front_shbuf_free(shbuf);
-		return ret;
-	}
+	ret = xen_front_pgdir_shbuf_alloc(&buf_cfg);
+	if (ret < 0)
+		goto fail_shbuf_alloc;
 
 	mutex_lock(&evtchnl->u.req.req_io_lock);
 
 	spin_lock_irqsave(&front_info->io_lock, flags);
 	req = be_prepare_req(evtchnl, XENDISPL_OP_DBUF_CREATE);
 	req->op.dbuf_create.gref_directory =
-			xen_drm_front_shbuf_get_dir_start(shbuf);
+			xen_front_pgdir_shbuf_get_dir_start(&dbuf->shbuf);
 	req->op.dbuf_create.buffer_sz = size;
 	req->op.dbuf_create.dbuf_cookie = dbuf_cookie;
 	req->op.dbuf_create.width = width;
@@ -221,7 +206,7 @@ int xen_drm_front_dbuf_create(struct xen_drm_front_info *front_info,
 	if (ret < 0)
 		goto fail;
 
-	ret = xen_drm_front_shbuf_map(shbuf);
+	ret = xen_front_pgdir_shbuf_map(&dbuf->shbuf);
 	if (ret < 0)
 		goto fail;
 
@@ -230,6 +215,7 @@ int xen_drm_front_dbuf_create(struct xen_drm_front_info *front_info,
 
 fail:
 	mutex_unlock(&evtchnl->u.req.req_io_lock);
+fail_shbuf_alloc:
 	dbuf_free(&front_info->dbuf_list, dbuf_cookie);
 	return ret;
 }
@@ -358,7 +344,6 @@ int xen_drm_front_page_flip(struct xen_drm_front_info *front_info,
 	if (unlikely(conn_idx >= front_info->num_evt_pairs))
 		return -EINVAL;
 
-	dbuf_flush_fb(&front_info->dbuf_list, fb_cookie);
 	evtchnl = &front_info->evt_pairs[conn_idx].req;
 
 	mutex_lock(&evtchnl->u.req.req_io_lock);