diff options
Diffstat (limited to 'sound/xen/xen_snd_front_shbuf.c')
| -rw-r--r-- | sound/xen/xen_snd_front_shbuf.c | 194 |
1 files changed, 0 insertions, 194 deletions
diff --git a/sound/xen/xen_snd_front_shbuf.c b/sound/xen/xen_snd_front_shbuf.c deleted file mode 100644 index 07ac176a41ba..000000000000 --- a/sound/xen/xen_snd_front_shbuf.c +++ /dev/null @@ -1,194 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 OR MIT - -/* - * Xen para-virtual sound device - * - * Copyright (C) 2016-2018 EPAM Systems Inc. - * - * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> - */ - -#include <linux/kernel.h> -#include <xen/xen.h> -#include <xen/xenbus.h> - -#include "xen_snd_front_shbuf.h" - -grant_ref_t xen_snd_front_shbuf_get_dir_start(struct xen_snd_front_shbuf *buf) -{ - if (!buf->grefs) - return GRANT_INVALID_REF; - - return buf->grefs[0]; -} - -void xen_snd_front_shbuf_clear(struct xen_snd_front_shbuf *buf) -{ - memset(buf, 0, sizeof(*buf)); -} - -void xen_snd_front_shbuf_free(struct xen_snd_front_shbuf *buf) -{ - int i; - - if (buf->grefs) { - 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); - free_pages_exact(buf->buffer, buf->buffer_sz); - xen_snd_front_shbuf_clear(buf); -} - -/* - * number of grant references a page can hold with respect to the - * xensnd_page_directory header - */ -#define XENSND_NUM_GREFS_PER_PAGE ((XEN_PAGE_SIZE - \ - offsetof(struct xensnd_page_directory, gref)) / \ - sizeof(grant_ref_t)) - -static void fill_page_dir(struct xen_snd_front_shbuf *buf, - int num_pages_dir) -{ - struct xensnd_page_directory *page_dir; - unsigned char *ptr; - int i, cur_gref, grefs_left, to_copy; - - ptr = buf->directory; - grefs_left = buf->num_grefs - num_pages_dir; - /* - * skip grant references at the beginning, they are for pages granted - * for the page directory itself - */ - cur_gref = num_pages_dir; - for (i = 0; i < num_pages_dir; i++) { - page_dir = (struct xensnd_page_directory *)ptr; - if (grefs_left <= XENSND_NUM_GREFS_PER_PAGE) { - to_copy = grefs_left; - page_dir->gref_dir_next_page = GRANT_INVALID_REF; - } else { - to_copy = XENSND_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 += XEN_PAGE_SIZE; - grefs_left -= to_copy; - cur_gref += to_copy; - } -} - -static int grant_references(struct xenbus_device *xb_dev, - struct xen_snd_front_shbuf *buf, - int num_pages_dir, int num_pages_buffer, - int num_grefs) -{ - grant_ref_t priv_gref_head; - unsigned long frame; - int ret, i, j, cur_ref; - int otherend_id; - - ret = gnttab_alloc_grant_references(num_grefs, &priv_gref_head); - if (ret) - return ret; - - buf->num_grefs = num_grefs; - otherend_id = xb_dev->otherend_id; - j = 0; - - for (i = 0; i < num_pages_dir; i++) { - cur_ref = gnttab_claim_grant_reference(&priv_gref_head); - if (cur_ref < 0) { - ret = cur_ref; - goto fail; - } - - frame = xen_page_to_gfn(virt_to_page(buf->directory + - XEN_PAGE_SIZE * i)); - gnttab_grant_foreign_access_ref(cur_ref, otherend_id, frame, 0); - buf->grefs[j++] = cur_ref; - } - - for (i = 0; i < num_pages_buffer; i++) { - cur_ref = gnttab_claim_grant_reference(&priv_gref_head); - if (cur_ref < 0) { - ret = cur_ref; - goto fail; - } - - frame = xen_page_to_gfn(virt_to_page(buf->buffer + - XEN_PAGE_SIZE * i)); - gnttab_grant_foreign_access_ref(cur_ref, otherend_id, frame, 0); - buf->grefs[j++] = cur_ref; - } - - gnttab_free_grant_references(priv_gref_head); - fill_page_dir(buf, num_pages_dir); - return 0; - -fail: - gnttab_free_grant_references(priv_gref_head); - return ret; -} - -static int alloc_int_buffers(struct xen_snd_front_shbuf *buf, - int num_pages_dir, int num_pages_buffer, - int num_grefs) -{ - buf->grefs = kcalloc(num_grefs, sizeof(*buf->grefs), GFP_KERNEL); - if (!buf->grefs) - return -ENOMEM; - - buf->directory = kcalloc(num_pages_dir, XEN_PAGE_SIZE, GFP_KERNEL); - if (!buf->directory) - goto fail; - - buf->buffer_sz = num_pages_buffer * XEN_PAGE_SIZE; - buf->buffer = alloc_pages_exact(buf->buffer_sz, GFP_KERNEL); - if (!buf->buffer) - goto fail; - - return 0; - -fail: - kfree(buf->grefs); - buf->grefs = NULL; - kfree(buf->directory); - buf->directory = NULL; - return -ENOMEM; -} - -int xen_snd_front_shbuf_alloc(struct xenbus_device *xb_dev, - struct xen_snd_front_shbuf *buf, - unsigned int buffer_sz) -{ - int num_pages_buffer, num_pages_dir, num_grefs; - int ret; - - xen_snd_front_shbuf_clear(buf); - - num_pages_buffer = DIV_ROUND_UP(buffer_sz, XEN_PAGE_SIZE); - /* number of pages the page directory consumes itself */ - num_pages_dir = DIV_ROUND_UP(num_pages_buffer, - XENSND_NUM_GREFS_PER_PAGE); - num_grefs = num_pages_buffer + num_pages_dir; - - ret = alloc_int_buffers(buf, num_pages_dir, - num_pages_buffer, num_grefs); - if (ret < 0) - return ret; - - ret = grant_references(xb_dev, buf, num_pages_dir, num_pages_buffer, - num_grefs); - if (ret < 0) - return ret; - - fill_page_dir(buf, num_pages_dir); - return 0; -} |