From: Oleksandr Andrushchenko oleksandr_andrushchenko@epam.com
Use page directory based shared buffer implementation now available as common code for Xen frontend drivers.
Signed-off-by: Oleksandr Andrushchenko oleksandr_andrushchenko@epam.com --- drivers/gpu/drm/xen/Kconfig | 1 + drivers/gpu/drm/xen/Makefile | 1 - drivers/gpu/drm/xen/xen_drm_front.c | 60 ++-- drivers/gpu/drm/xen/xen_drm_front_gem.c | 1 - drivers/gpu/drm/xen/xen_drm_front_shbuf.c | 414 ---------------------- drivers/gpu/drm/xen/xen_drm_front_shbuf.h | 64 ---- 6 files changed, 30 insertions(+), 511 deletions(-) delete mode 100644 drivers/gpu/drm/xen/xen_drm_front_shbuf.c delete mode 100644 drivers/gpu/drm/xen/xen_drm_front_shbuf.h
diff --git a/drivers/gpu/drm/xen/Kconfig b/drivers/gpu/drm/xen/Kconfig index 4cca160782ab..f969d486855d 100644 --- a/drivers/gpu/drm/xen/Kconfig +++ b/drivers/gpu/drm/xen/Kconfig @@ -12,6 +12,7 @@ config DRM_XEN_FRONTEND select DRM_KMS_HELPER select VIDEOMODE_HELPERS select XEN_XENBUS_FRONTEND + select XEN_FRONT_PGDIR_SHBUF help Choose this option if you want to enable a para-virtualized frontend DRM/KMS driver for Xen guest OSes. diff --git a/drivers/gpu/drm/xen/Makefile b/drivers/gpu/drm/xen/Makefile index 712afff5ffc3..825905f67faa 100644 --- a/drivers/gpu/drm/xen/Makefile +++ b/drivers/gpu/drm/xen/Makefile @@ -4,7 +4,6 @@ drm_xen_front-objs := xen_drm_front.o \ xen_drm_front_kms.o \ xen_drm_front_conn.o \ xen_drm_front_evtchnl.o \ - xen_drm_front_shbuf.o \ xen_drm_front_cfg.o \ xen_drm_front_gem.o
diff --git a/drivers/gpu/drm/xen/xen_drm_front.c b/drivers/gpu/drm/xen/xen_drm_front.c index 6b6d5ab82ec3..9597544fecc1 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, @@ -64,11 +57,14 @@ static struct xen_drm_front_dbuf *dbuf_get(struct list_head *dbuf_list,
static void dbuf_flush_fb(struct list_head *dbuf_list, u64 fb_cookie) { +#if IS_ENABLED(CONFIG_X86) 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); + drm_clflush_pages(buf->shbuf.pages, + buf->shbuf.num_pages); +#endif }
static void dbuf_free(struct list_head *dbuf_list, u64 dbuf_cookie) @@ -78,8 +74,8 @@ 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 +87,8 @@ 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 +167,9 @@ 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 +177,29 @@ 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 +218,7 @@ 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 +227,7 @@ 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; } diff --git a/drivers/gpu/drm/xen/xen_drm_front_gem.c b/drivers/gpu/drm/xen/xen_drm_front_gem.c index c85bfe7571cb..53be4c7dc0a4 100644 --- a/drivers/gpu/drm/xen/xen_drm_front_gem.c +++ b/drivers/gpu/drm/xen/xen_drm_front_gem.c @@ -22,7 +22,6 @@ #include <xen/balloon.h>
#include "xen_drm_front.h" -#include "xen_drm_front_shbuf.h"
struct xen_gem_object { struct drm_gem_object base; diff --git a/drivers/gpu/drm/xen/xen_drm_front_shbuf.c b/drivers/gpu/drm/xen/xen_drm_front_shbuf.c deleted file mode 100644 index d333b67cc1a0..000000000000 --- a/drivers/gpu/drm/xen/xen_drm_front_shbuf.c +++ /dev/null @@ -1,414 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 OR MIT - -/* - * Xen para-virtual DRM device - * - * Copyright (C) 2016-2018 EPAM Systems Inc. - * - * Author: Oleksandr Andrushchenko oleksandr_andrushchenko@epam.com - */ - -#include <drm/drmP.h> - -#if defined(CONFIG_X86) -#include <drm/drm_cache.h> -#endif -#include <linux/errno.h> -#include <linux/mm.h> - -#include <asm/xen/hypervisor.h> -#include <xen/balloon.h> -#include <xen/xen.h> -#include <xen/xenbus.h> -#include <xen/interface/io/ring.h> -#include <xen/interface/io/displif.h> - -#include "xen_drm_front.h" -#include "xen_drm_front_shbuf.h" - -struct xen_drm_front_shbuf_ops { - /* - * Calculate number of grefs required to handle this buffer, - * e.g. if grefs are required for page directory only or the buffer - * pages as well. - */ - void (*calc_num_grefs)(struct xen_drm_front_shbuf *buf); - /* Fill page directory according to para-virtual display protocol. */ - void (*fill_page_dir)(struct xen_drm_front_shbuf *buf); - /* Claim grant references for the pages of the buffer. */ - int (*grant_refs_for_buffer)(struct xen_drm_front_shbuf *buf, - grant_ref_t *priv_gref_head, int gref_idx); - /* Map grant references of the buffer. */ - int (*map)(struct xen_drm_front_shbuf *buf); - /* Unmap grant references of the buffer. */ - int (*unmap)(struct xen_drm_front_shbuf *buf); -}; - -grant_ref_t xen_drm_front_shbuf_get_dir_start(struct xen_drm_front_shbuf *buf) -{ - if (!buf->grefs) - return GRANT_INVALID_REF; - - return buf->grefs[0]; -} - -int xen_drm_front_shbuf_map(struct xen_drm_front_shbuf *buf) -{ - if (buf->ops->map) - return buf->ops->map(buf); - - /* no need to map own grant references */ - return 0; -} - -int xen_drm_front_shbuf_unmap(struct xen_drm_front_shbuf *buf) -{ - if (buf->ops->unmap) - return buf->ops->unmap(buf); - - /* no need to unmap own grant references */ - return 0; -} - -void xen_drm_front_shbuf_flush(struct xen_drm_front_shbuf *buf) -{ -#if defined(CONFIG_X86) - drm_clflush_pages(buf->pages, buf->num_pages); -#endif -} - -void xen_drm_front_shbuf_free(struct xen_drm_front_shbuf *buf) -{ - if (buf->grefs) { - int i; - - for (i = 0; i < buf->num_grefs; i++) - if (buf->grefs[i] != GRANT_INVALID_REF) - gnttab_end_foreign_access(buf->grefs[i], - 0, 0UL); - } - kfree(buf->grefs); - kfree(buf->directory); - kfree(buf); -} - -/* - * number of grefs a page can hold with respect to the - * struct xendispl_page_directory header - */ -#define XEN_DRM_NUM_GREFS_PER_PAGE ((PAGE_SIZE - \ - offsetof(struct xendispl_page_directory, gref)) / \ - sizeof(grant_ref_t)) - -static int get_num_pages_dir(struct xen_drm_front_shbuf *buf) -{ - /* number of pages the page directory consumes itself */ - return DIV_ROUND_UP(buf->num_pages, XEN_DRM_NUM_GREFS_PER_PAGE); -} - -static void backend_calc_num_grefs(struct xen_drm_front_shbuf *buf) -{ - /* only for pages the page directory consumes itself */ - buf->num_grefs = get_num_pages_dir(buf); -} - -static void guest_calc_num_grefs(struct xen_drm_front_shbuf *buf) -{ - /* - * number of pages the page directory consumes itself - * plus grefs for the buffer pages - */ - buf->num_grefs = get_num_pages_dir(buf) + buf->num_pages; -} - -#define xen_page_to_vaddr(page) \ - ((uintptr_t)pfn_to_kaddr(page_to_xen_pfn(page))) - -static int backend_unmap(struct xen_drm_front_shbuf *buf) -{ - struct gnttab_unmap_grant_ref *unmap_ops; - int i, ret; - - if (!buf->pages || !buf->backend_map_handles || !buf->grefs) - return 0; - - unmap_ops = kcalloc(buf->num_pages, sizeof(*unmap_ops), - GFP_KERNEL); - if (!unmap_ops) { - DRM_ERROR("Failed to get memory while unmapping\n"); - return -ENOMEM; - } - - for (i = 0; i < buf->num_pages; i++) { - phys_addr_t addr; - - addr = xen_page_to_vaddr(buf->pages[i]); - gnttab_set_unmap_op(&unmap_ops[i], addr, GNTMAP_host_map, - buf->backend_map_handles[i]); - } - - ret = gnttab_unmap_refs(unmap_ops, NULL, buf->pages, - buf->num_pages); - - for (i = 0; i < buf->num_pages; i++) { - if (unlikely(unmap_ops[i].status != GNTST_okay)) - DRM_ERROR("Failed to unmap page %d: %d\n", - i, unmap_ops[i].status); - } - - if (ret) - DRM_ERROR("Failed to unmap grant references, ret %d", ret); - - kfree(unmap_ops); - kfree(buf->backend_map_handles); - buf->backend_map_handles = NULL; - return ret; -} - -static int backend_map(struct xen_drm_front_shbuf *buf) -{ - struct gnttab_map_grant_ref *map_ops = NULL; - unsigned char *ptr; - int ret, cur_gref, cur_dir_page, cur_page, grefs_left; - - map_ops = kcalloc(buf->num_pages, sizeof(*map_ops), GFP_KERNEL); - if (!map_ops) - return -ENOMEM; - - buf->backend_map_handles = kcalloc(buf->num_pages, - sizeof(*buf->backend_map_handles), - GFP_KERNEL); - if (!buf->backend_map_handles) { - kfree(map_ops); - return -ENOMEM; - } - - /* - * read page directory to get grefs from the backend: for external - * buffer we only allocate buf->grefs for the page directory, - * so buf->num_grefs has number of pages in the page directory itself - */ - ptr = buf->directory; - grefs_left = buf->num_pages; - cur_page = 0; - for (cur_dir_page = 0; cur_dir_page < buf->num_grefs; cur_dir_page++) { - struct xendispl_page_directory *page_dir = - (struct xendispl_page_directory *)ptr; - int to_copy = XEN_DRM_NUM_GREFS_PER_PAGE; - - if (to_copy > grefs_left) - to_copy = grefs_left; - - for (cur_gref = 0; cur_gref < to_copy; cur_gref++) { - phys_addr_t addr; - - addr = xen_page_to_vaddr(buf->pages[cur_page]); - gnttab_set_map_op(&map_ops[cur_page], addr, - GNTMAP_host_map, - page_dir->gref[cur_gref], - buf->xb_dev->otherend_id); - cur_page++; - } - - grefs_left -= to_copy; - ptr += PAGE_SIZE; - } - ret = gnttab_map_refs(map_ops, NULL, buf->pages, buf->num_pages); - - /* save handles even if error, so we can unmap */ - for (cur_page = 0; cur_page < buf->num_pages; cur_page++) { - buf->backend_map_handles[cur_page] = map_ops[cur_page].handle; - if (unlikely(map_ops[cur_page].status != GNTST_okay)) - DRM_ERROR("Failed to map page %d: %d\n", - cur_page, map_ops[cur_page].status); - } - - if (ret) { - DRM_ERROR("Failed to map grant references, ret %d", ret); - backend_unmap(buf); - } - - kfree(map_ops); - return ret; -} - -static void backend_fill_page_dir(struct xen_drm_front_shbuf *buf) -{ - struct xendispl_page_directory *page_dir; - unsigned char *ptr; - int i, num_pages_dir; - - ptr = buf->directory; - num_pages_dir = get_num_pages_dir(buf); - - /* fill only grefs for the page directory itself */ - for (i = 0; i < num_pages_dir - 1; i++) { - page_dir = (struct xendispl_page_directory *)ptr; - - page_dir->gref_dir_next_page = buf->grefs[i + 1]; - ptr += PAGE_SIZE; - } - /* last page must say there is no more pages */ - page_dir = (struct xendispl_page_directory *)ptr; - page_dir->gref_dir_next_page = GRANT_INVALID_REF; -} - -static void guest_fill_page_dir(struct xen_drm_front_shbuf *buf) -{ - unsigned char *ptr; - int cur_gref, grefs_left, to_copy, i, num_pages_dir; - - ptr = buf->directory; - num_pages_dir = get_num_pages_dir(buf); - - /* - * while copying, skip grefs at start, they are for pages - * granted for the page directory itself - */ - cur_gref = num_pages_dir; - grefs_left = buf->num_pages; - for (i = 0; i < num_pages_dir; i++) { - struct xendispl_page_directory *page_dir = - (struct xendispl_page_directory *)ptr; - - if (grefs_left <= XEN_DRM_NUM_GREFS_PER_PAGE) { - to_copy = grefs_left; - page_dir->gref_dir_next_page = GRANT_INVALID_REF; - } else { - to_copy = XEN_DRM_NUM_GREFS_PER_PAGE; - page_dir->gref_dir_next_page = buf->grefs[i + 1]; - } - memcpy(&page_dir->gref, &buf->grefs[cur_gref], - to_copy * sizeof(grant_ref_t)); - ptr += PAGE_SIZE; - grefs_left -= to_copy; - cur_gref += to_copy; - } -} - -static int guest_grant_refs_for_buffer(struct xen_drm_front_shbuf *buf, - grant_ref_t *priv_gref_head, - int gref_idx) -{ - int i, cur_ref, otherend_id; - - otherend_id = buf->xb_dev->otherend_id; - for (i = 0; i < buf->num_pages; i++) { - cur_ref = gnttab_claim_grant_reference(priv_gref_head); - if (cur_ref < 0) - return cur_ref; - - gnttab_grant_foreign_access_ref(cur_ref, otherend_id, - xen_page_to_gfn(buf->pages[i]), - 0); - buf->grefs[gref_idx++] = cur_ref; - } - return 0; -} - -static int grant_references(struct xen_drm_front_shbuf *buf) -{ - grant_ref_t priv_gref_head; - int ret, i, j, cur_ref; - int otherend_id, num_pages_dir; - - ret = gnttab_alloc_grant_references(buf->num_grefs, &priv_gref_head); - if (ret < 0) { - DRM_ERROR("Cannot allocate grant references\n"); - return ret; - } - - otherend_id = buf->xb_dev->otherend_id; - j = 0; - num_pages_dir = get_num_pages_dir(buf); - for (i = 0; i < num_pages_dir; i++) { - unsigned long frame; - - cur_ref = gnttab_claim_grant_reference(&priv_gref_head); - if (cur_ref < 0) - return cur_ref; - - frame = xen_page_to_gfn(virt_to_page(buf->directory + - PAGE_SIZE * i)); - gnttab_grant_foreign_access_ref(cur_ref, otherend_id, frame, 0); - buf->grefs[j++] = cur_ref; - } - - if (buf->ops->grant_refs_for_buffer) { - ret = buf->ops->grant_refs_for_buffer(buf, &priv_gref_head, j); - if (ret) - return ret; - } - - gnttab_free_grant_references(priv_gref_head); - return 0; -} - -static int alloc_storage(struct xen_drm_front_shbuf *buf) -{ - buf->grefs = kcalloc(buf->num_grefs, sizeof(*buf->grefs), GFP_KERNEL); - if (!buf->grefs) - return -ENOMEM; - - buf->directory = kcalloc(get_num_pages_dir(buf), PAGE_SIZE, GFP_KERNEL); - if (!buf->directory) - return -ENOMEM; - - return 0; -} - -/* - * For be allocated buffers we don't need grant_refs_for_buffer as those - * grant references are allocated at backend side - */ -static const struct xen_drm_front_shbuf_ops backend_ops = { - .calc_num_grefs = backend_calc_num_grefs, - .fill_page_dir = backend_fill_page_dir, - .map = backend_map, - .unmap = backend_unmap -}; - -/* For locally granted references we do not need to map/unmap the references */ -static const struct xen_drm_front_shbuf_ops local_ops = { - .calc_num_grefs = guest_calc_num_grefs, - .fill_page_dir = guest_fill_page_dir, - .grant_refs_for_buffer = guest_grant_refs_for_buffer, -}; - -struct xen_drm_front_shbuf * -xen_drm_front_shbuf_alloc(struct xen_drm_front_shbuf_cfg *cfg) -{ - struct xen_drm_front_shbuf *buf; - int ret; - - buf = kzalloc(sizeof(*buf), GFP_KERNEL); - if (!buf) - return ERR_PTR(-ENOMEM); - - if (cfg->be_alloc) - buf->ops = &backend_ops; - else - buf->ops = &local_ops; - - buf->xb_dev = cfg->xb_dev; - buf->num_pages = DIV_ROUND_UP(cfg->size, PAGE_SIZE); - buf->pages = cfg->pages; - - buf->ops->calc_num_grefs(buf); - - ret = alloc_storage(buf); - if (ret) - goto fail; - - ret = grant_references(buf); - if (ret) - goto fail; - - buf->ops->fill_page_dir(buf); - - return buf; - -fail: - xen_drm_front_shbuf_free(buf); - return ERR_PTR(ret); -} diff --git a/drivers/gpu/drm/xen/xen_drm_front_shbuf.h b/drivers/gpu/drm/xen/xen_drm_front_shbuf.h deleted file mode 100644 index 7545c692539e..000000000000 --- a/drivers/gpu/drm/xen/xen_drm_front_shbuf.h +++ /dev/null @@ -1,64 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 OR MIT */ - -/* - * Xen para-virtual DRM device - * - * Copyright (C) 2016-2018 EPAM Systems Inc. - * - * Author: Oleksandr Andrushchenko oleksandr_andrushchenko@epam.com - */ - -#ifndef __XEN_DRM_FRONT_SHBUF_H_ -#define __XEN_DRM_FRONT_SHBUF_H_ - -#include <linux/kernel.h> -#include <linux/scatterlist.h> - -#include <xen/grant_table.h> - -struct xen_drm_front_shbuf { - /* - * number of references granted for the backend use: - * - for allocated/imported dma-buf's this holds number of grant - * references for the page directory and pages of the buffer - * - for the buffer provided by the backend this holds number of - * grant references for the page directory as grant references for - * the buffer will be provided by the backend - */ - int num_grefs; - grant_ref_t *grefs; - unsigned char *directory; - - int num_pages; - struct page **pages; - - struct xenbus_device *xb_dev; - - /* these are the ops used internally depending on be_alloc mode */ - const struct xen_drm_front_shbuf_ops *ops; - - /* Xen map handles for the buffer allocated by the backend */ - grant_handle_t *backend_map_handles; -}; - -struct xen_drm_front_shbuf_cfg { - struct xenbus_device *xb_dev; - size_t size; - struct page **pages; - bool be_alloc; -}; - -struct xen_drm_front_shbuf * -xen_drm_front_shbuf_alloc(struct xen_drm_front_shbuf_cfg *cfg); - -grant_ref_t xen_drm_front_shbuf_get_dir_start(struct xen_drm_front_shbuf *buf); - -int xen_drm_front_shbuf_map(struct xen_drm_front_shbuf *buf); - -int xen_drm_front_shbuf_unmap(struct xen_drm_front_shbuf *buf); - -void xen_drm_front_shbuf_flush(struct xen_drm_front_shbuf *buf); - -void xen_drm_front_shbuf_free(struct xen_drm_front_shbuf *buf); - -#endif /* __XEN_DRM_FRONT_SHBUF_H_ */