diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-12-26 22:35:07 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-12-26 22:35:07 +0300 |
commit | 460023a5d1d2aa0f733b6708b2fae5ea9f9dfec0 (patch) | |
tree | 75ac3b22722dab7e006ed229a8c8538a3e8e537c /drivers | |
parent | a5f2bd479f58f171a16a9a4f3b4e748ab3057c0f (diff) | |
parent | 58f9d806d16a38ed3bae11e2ada83393436a4956 (diff) | |
download | linux-460023a5d1d2aa0f733b6708b2fae5ea9f9dfec0.tar.xz |
Merge tag 'for-linus-4.21-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen updates from Juergen Gross:
"Xen features and fixes:
- a series to enable KVM guests to be booted by qemu via the Xen PVH
boot entry for speeding up KVM guest tests
- a series for a common driver to be used by Xen PV frontends (right
now drm and sound)
- two other fixes in Xen related code"
* tag 'for-linus-4.21-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
ALSA: xen-front: Use Xen common shared buffer implementation
drm/xen-front: Use Xen common shared buffer implementation
xen: Introduce shared buffer helpers for page directory...
xen/pciback: Check dev_data before using it
kprobes/x86/xen: blacklist non-attachable xen interrupt functions
KVM: x86: Allow Qemu/KVM to use PVH entry point
xen/pvh: Add memory map pointer to hvm_start_info struct
xen/pvh: Move Xen code for getting mem map via hcall out of common file
xen/pvh: Move Xen specific PVH VM initialization out of common file
xen/pvh: Create a new file for Xen specific PVH code
xen/pvh: Move PVH entry code out of Xen specific tree
xen/pvh: Split CONFIG_XEN_PVH into CONFIG_PVH and CONFIG_XEN_PVH
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/gpu/drm/xen/Kconfig | 1 | ||||
-rw-r--r-- | drivers/gpu/drm/xen/Makefile | 1 | ||||
-rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front.c | 65 | ||||
-rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front_gem.c | 1 | ||||
-rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front_shbuf.c | 414 | ||||
-rw-r--r-- | drivers/gpu/drm/xen/xen_drm_front_shbuf.h | 64 | ||||
-rw-r--r-- | drivers/xen/Kconfig | 3 | ||||
-rw-r--r-- | drivers/xen/Makefile | 1 | ||||
-rw-r--r-- | drivers/xen/xen-front-pgdir-shbuf.c | 553 | ||||
-rw-r--r-- | drivers/xen/xen-pciback/pci_stub.c | 3 |
10 files changed, 585 insertions, 521 deletions
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..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); diff --git a/drivers/gpu/drm/xen/xen_drm_front_gem.c b/drivers/gpu/drm/xen/xen_drm_front_gem.c index 47ff019d3aef..28bc501af450 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_ */ diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig index 815b9e9bb975..838b66a9a0e7 100644 --- a/drivers/xen/Kconfig +++ b/drivers/xen/Kconfig @@ -340,4 +340,7 @@ config XEN_SYMS config XEN_HAVE_VPMU bool +config XEN_FRONT_PGDIR_SHBUF + tristate + endmenu diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile index 3e542f60f29f..c48927a58e10 100644 --- a/drivers/xen/Makefile +++ b/drivers/xen/Makefile @@ -44,3 +44,4 @@ xen-gntdev-y := gntdev.o xen-gntdev-$(CONFIG_XEN_GNTDEV_DMABUF) += gntdev-dmabuf.o xen-gntalloc-y := gntalloc.o xen-privcmd-y := privcmd.o privcmd-buf.o +obj-$(CONFIG_XEN_FRONT_PGDIR_SHBUF) += xen-front-pgdir-shbuf.o diff --git a/drivers/xen/xen-front-pgdir-shbuf.c b/drivers/xen/xen-front-pgdir-shbuf.c new file mode 100644 index 000000000000..48a658dc7ccf --- /dev/null +++ b/drivers/xen/xen-front-pgdir-shbuf.c @@ -0,0 +1,553 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT + +/* + * Xen frontend/backend page directory based shared buffer + * helper module. + * + * Copyright (C) 2018 EPAM Systems Inc. + * + * Author: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com> + */ + +#include <linux/module.h> +#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/xen-front-pgdir-shbuf.h> + +#ifndef GRANT_INVALID_REF +/* + * FIXME: usage of grant reference 0 as invalid grant reference: + * grant reference 0 is valid, but never exposed to a PV driver, + * because of the fact it is already in use/reserved by the PV console. + */ +#define GRANT_INVALID_REF 0 +#endif + +/** + * This structure represents the structure of a shared page + * that contains grant references to the pages of the shared + * buffer. This structure is common to many Xen para-virtualized + * protocols at include/xen/interface/io/ + */ +struct xen_page_directory { + grant_ref_t gref_dir_next_page; + grant_ref_t gref[1]; /* Variable length */ +}; + +/** + * Shared buffer ops which are differently implemented + * depending on the allocation mode, e.g. if the buffer + * is allocated by the corresponding backend or frontend. + * Some of the operations. + */ +struct xen_front_pgdir_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_front_pgdir_shbuf *buf); + + /* Fill page directory according to para-virtual display protocol. */ + void (*fill_page_dir)(struct xen_front_pgdir_shbuf *buf); + + /* Claim grant references for the pages of the buffer. */ + int (*grant_refs_for_buffer)(struct xen_front_pgdir_shbuf *buf, + grant_ref_t *priv_gref_head, int gref_idx); + + /* Map grant references of the buffer. */ + int (*map)(struct xen_front_pgdir_shbuf *buf); + + /* Unmap grant references of the buffer. */ + int (*unmap)(struct xen_front_pgdir_shbuf *buf); +}; + +/** + * Get granted reference to the very first page of the + * page directory. Usually this is passed to the backend, + * so it can find/fill the grant references to the buffer's + * pages. + * + * \param buf shared buffer which page directory is of interest. + * \return granted reference to the very first page of the + * page directory. + */ +grant_ref_t +xen_front_pgdir_shbuf_get_dir_start(struct xen_front_pgdir_shbuf *buf) +{ + if (!buf->grefs) + return GRANT_INVALID_REF; + + return buf->grefs[0]; +} +EXPORT_SYMBOL_GPL(xen_front_pgdir_shbuf_get_dir_start); + +/** + * Map granted references of the shared buffer. + * + * Depending on the shared buffer mode of allocation + * (be_alloc flag) this can either do nothing (for buffers + * shared by the frontend itself) or map the provided granted + * references onto the backing storage (buf->pages). + * + * \param buf shared buffer which grants to be maped. + * \return zero on success or a negative number on failure. + */ +int xen_front_pgdir_shbuf_map(struct xen_front_pgdir_shbuf *buf) +{ + if (buf->ops && buf->ops->map) + return buf->ops->map(buf); + + /* No need to map own grant references. */ + return 0; +} +EXPORT_SYMBOL_GPL(xen_front_pgdir_shbuf_map); + +/** + * Unmap granted references of the shared buffer. + * + * Depending on the shared buffer mode of allocation + * (be_alloc flag) this can either do nothing (for buffers + * shared by the frontend itself) or unmap the provided granted + * references. + * + * \param buf shared buffer which grants to be unmaped. + * \return zero on success or a negative number on failure. + */ +int xen_front_pgdir_shbuf_unmap(struct xen_front_pgdir_shbuf *buf) +{ + if (buf->ops && buf->ops->unmap) + return buf->ops->unmap(buf); + + /* No need to unmap own grant references. */ + return 0; +} +EXPORT_SYMBOL_GPL(xen_front_pgdir_shbuf_unmap); + +/** + * Free all the resources of the shared buffer. + * + * \param buf shared buffer which resources to be freed. + */ +void xen_front_pgdir_shbuf_free(struct xen_front_pgdir_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); +} +EXPORT_SYMBOL_GPL(xen_front_pgdir_shbuf_free); + +/* + * Number of grefs a page can hold with respect to the + * struct xen_page_directory header. + */ +#define XEN_NUM_GREFS_PER_PAGE ((PAGE_SIZE - \ + offsetof(struct xen_page_directory, \ + gref)) / sizeof(grant_ref_t)) + +/** + * Get the number of pages the page directory consumes itself. + * + * \param buf shared buffer. + */ +static int get_num_pages_dir(struct xen_front_pgdir_shbuf *buf) +{ + return DIV_ROUND_UP(buf->num_pages, XEN_NUM_GREFS_PER_PAGE); +} + +/** + * Calculate the number of grant references needed to share the buffer + * and its pages when backend allocates the buffer. + * + * \param buf shared buffer. + */ +static void backend_calc_num_grefs(struct xen_front_pgdir_shbuf *buf) +{ + /* Only for pages the page directory consumes itself. */ + buf->num_grefs = get_num_pages_dir(buf); +} + +/** + * Calculate the number of grant references needed to share the buffer + * and its pages when frontend allocates the buffer. + * + * \param buf shared buffer. + */ +static void guest_calc_num_grefs(struct xen_front_pgdir_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))) + +/** + * Unmap the buffer previously mapped with grant references + * provided by the backend. + * + * \param buf shared buffer. + * \return zero on success or a negative number on failure. + */ +static int backend_unmap(struct xen_front_pgdir_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) + 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)) + dev_err(&buf->xb_dev->dev, + "Failed to unmap page %d: %d\n", + i, unmap_ops[i].status); + } + + if (ret) + dev_err(&buf->xb_dev->dev, + "Failed to unmap grant references, ret %d", ret); + + kfree(unmap_ops); + kfree(buf->backend_map_handles); + buf->backend_map_handles = NULL; + return ret; +} + +/** + * Map the buffer with grant references provided by the backend. + * + * \param buf shared buffer. + * \return zero on success or a negative number on failure. + */ +static int backend_map(struct xen_front_pgdir_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 xen_page_directory *page_dir = + (struct xen_page_directory *)ptr; + int to_copy = XEN_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)) + dev_err(&buf->xb_dev->dev, + "Failed to map page %d: %d\n", + cur_page, map_ops[cur_page].status); + } + + if (ret) { + dev_err(&buf->xb_dev->dev, + "Failed to map grant references, ret %d", ret); + backend_unmap(buf); + } + + kfree(map_ops); + return ret; +} + +/** + * Fill page directory with grant references to the pages of the + * page directory itself. + * + * The grant references to the buffer pages are provided by the + * backend in this case. + * + * \param buf shared buffer. + */ +static void backend_fill_page_dir(struct xen_front_pgdir_shbuf *buf) +{ + struct xen_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 xen_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 xen_page_directory *)ptr; + page_dir->gref_dir_next_page = GRANT_INVALID_REF; +} + +/** + * Fill page directory with grant references to the pages of the + * page directory and the buffer we share with the backend. + * + * \param buf shared buffer. + */ +static void guest_fill_page_dir(struct xen_front_pgdir_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 xen_page_directory *page_dir = + (struct xen_page_directory *)ptr; + + if (grefs_left <= XEN_NUM_GREFS_PER_PAGE) { + to_copy = grefs_left; + page_dir->gref_dir_next_page = GRANT_INVALID_REF; + } else { + to_copy = XEN_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; + } +} + +/** + * Grant references to the frontend's buffer pages. + * + * These will be shared with the backend, so it can + * access the buffer's data. + * + * \param buf shared buffer. + * \return zero on success or a negative number on failure. + */ +static int guest_grant_refs_for_buffer(struct xen_front_pgdir_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; +} + +/** + * Grant all the references needed to share the buffer. + * + * Grant references to the page directory pages and, if + * needed, also to the pages of the shared buffer data. + * + * \param buf shared buffer. + * \return zero on success or a negative number on failure. + */ +static int grant_references(struct xen_front_pgdir_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) { + dev_err(&buf->xb_dev->dev, + "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; +} + +/** + * Allocate all required structures to mange shared buffer. + * + * \param buf shared buffer. + * \return zero on success or a negative number on failure. + */ +static int alloc_storage(struct xen_front_pgdir_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 backend allocated buffers we don't need grant_refs_for_buffer + * as those grant references are allocated at backend side. + */ +static const struct xen_front_pgdir_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_front_pgdir_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, +}; + +/** + * Allocate a new instance of a shared buffer. + * + * \param cfg configuration to be used while allocating a new shared buffer. + * \return zero on success or a negative number on failure. + */ +int xen_front_pgdir_shbuf_alloc(struct xen_front_pgdir_shbuf_cfg *cfg) +{ + struct xen_front_pgdir_shbuf *buf = cfg->pgdir; + int ret; + + if (cfg->be_alloc) + buf->ops = &backend_ops; + else + buf->ops = &local_ops; + buf->xb_dev = cfg->xb_dev; + buf->num_pages = cfg->num_pages; + 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 0; + +fail: + xen_front_pgdir_shbuf_free(buf); + return ret; +} +EXPORT_SYMBOL_GPL(xen_front_pgdir_shbuf_alloc); + +MODULE_DESCRIPTION("Xen frontend/backend page directory based " + "shared buffer handling"); +MODULE_AUTHOR("Oleksandr Andrushchenko"); +MODULE_LICENSE("GPL"); diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c index 59661db144e5..097410a7cdb7 100644 --- a/drivers/xen/xen-pciback/pci_stub.c +++ b/drivers/xen/xen-pciback/pci_stub.c @@ -106,7 +106,8 @@ static void pcistub_device_release(struct kref *kref) * is called from "unbind" which takes a device_lock mutex. */ __pci_reset_function_locked(dev); - if (pci_load_and_free_saved_state(dev, &dev_data->pci_saved_state)) + if (dev_data && + pci_load_and_free_saved_state(dev, &dev_data->pci_saved_state)) dev_info(&dev->dev, "Could not reload PCI state\n"); else pci_restore_state(dev); |