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xen: features and fixes for 4.19-rc1

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Merge tag 'for-linus-4.19-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from Juergen Gross:

 - add dma-buf functionality to Xen grant table handling

 - fix for booting the kernel as Xen PVH dom0

 - fix for booting the kernel as a Xen PV guest with
   CONFIG_DEBUG_VIRTUAL enabled

 - other minor performance and style fixes

* tag 'for-linus-4.19-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/balloon: fix balloon initialization for PVH Dom0
  xen: don't use privcmd_call() from xen_mc_flush()
  xen/pv: Call get_cpu_address_sizes to set x86_virt/phys_bits
  xen/biomerge: Use true and false for boolean values
  xen/gntdev: don't dereference a null gntdev_dmabuf on allocation failure
  xen/spinlock: Don't use pvqspinlock if only 1 vCPU
  xen/gntdev: Implement dma-buf import functionality
  xen/gntdev: Implement dma-buf export functionality
  xen/gntdev: Add initial support for dma-buf UAPI
  xen/gntdev: Make private routines/structures accessible
  xen/gntdev: Allow mappings for DMA buffers
  xen/grant-table: Allow allocating buffers suitable for DMA
  xen/balloon: Share common memory reservation routines
  xen/grant-table: Make set/clear page private code shared
This commit is contained in:
Linus Torvalds 2018-08-14 16:54:22 -07:00
commit 31130a16d4
20 changed files with 1634 additions and 171 deletions
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25
arch/x86/include/asm/xen/hypercall.h
View File

@ -209,24 +209,37 @@ extern struct { char _entry[32]; } hypercall_page[];
})
static inline long
privcmd_call(unsigned call,
unsigned long a1, unsigned long a2,
unsigned long a3, unsigned long a4,
unsigned long a5)
xen_single_call(unsigned int call,
unsigned long a1, unsigned long a2,
unsigned long a3, unsigned long a4,
unsigned long a5)
{
__HYPERCALL_DECLS;
__HYPERCALL_5ARG(a1, a2, a3, a4, a5);
stac();
asm volatile(CALL_NOSPEC
: __HYPERCALL_5PARAM
: [thunk_target] "a" (&hypercall_page[call])
: __HYPERCALL_CLOBBER5);
clac();
return (long)__res;
}
static inline long
privcmd_call(unsigned int call,
unsigned long a1, unsigned long a2,
unsigned long a3, unsigned long a4,
unsigned long a5)
{
long res;
stac();
res = xen_single_call(call, a1, a2, a3, a4, a5);
clac();
return res;
}
static inline int
HYPERVISOR_set_trap_table(struct trap_info *table)
{

2
arch/x86/kernel/cpu/common.c
View File

@ -905,7 +905,7 @@ void get_cpu_cap(struct cpuinfo_x86 *c)
apply_forced_caps(c);
}
static void get_cpu_address_sizes(struct cpuinfo_x86 *c)
void get_cpu_address_sizes(struct cpuinfo_x86 *c)
{
u32 eax, ebx, ecx, edx;

1
arch/x86/kernel/cpu/cpu.h
View File

@ -46,6 +46,7 @@ extern const struct cpu_dev *const __x86_cpu_dev_start[],
*const __x86_cpu_dev_end[];
extern void get_cpu_cap(struct cpuinfo_x86 *c);
extern void get_cpu_address_sizes(struct cpuinfo_x86 *c);
extern void cpu_detect_cache_sizes(struct cpuinfo_x86 *c);
extern void init_scattered_cpuid_features(struct cpuinfo_x86 *c);
extern u32 get_scattered_cpuid_leaf(unsigned int level,

3
arch/x86/xen/enlighten_pv.c
View File

@ -1256,6 +1256,9 @@ asmlinkage __visible void __init xen_start_kernel(void)
get_cpu_cap(&boot_cpu_data);
x86_configure_nx();
/* Determine virtual and physical address sizes */
get_cpu_address_sizes(&boot_cpu_data);
/* Let's presume PV guests always boot on vCPU with id 0. */
per_cpu(xen_vcpu_id, 0) = 0;

6
arch/x86/xen/multicalls.c
View File

@ -80,9 +80,9 @@ void xen_mc_flush(void)
and just do the call directly. */
mc = &b->entries[0];
mc->result = privcmd_call(mc->op,
mc->args[0], mc->args[1], mc->args[2],
mc->args[3], mc->args[4]);
mc->result = xen_single_call(mc->op, mc->args[0], mc->args[1],
mc->args[2], mc->args[3],
mc->args[4]);
ret = mc->result < 0;
break;

4
arch/x86/xen/spinlock.c
View File

@ -130,6 +130,10 @@ PV_CALLEE_SAVE_REGS_THUNK(xen_vcpu_stolen);
void __init xen_init_spinlocks(void)
{
/* Don't need to use pvqspinlock code if there is only 1 vCPU. */
if (num_possible_cpus() == 1)
xen_pvspin = false;
if (!xen_pvspin) {
printk(KERN_DEBUG "xen: PV spinlocks disabled\n");
return;

24
drivers/xen/Kconfig
View File

@ -152,6 +152,16 @@ config XEN_GNTDEV
help
Allows userspace processes to use grants.
config XEN_GNTDEV_DMABUF
bool "Add support for dma-buf grant access device driver extension"
depends on XEN_GNTDEV && XEN_GRANT_DMA_ALLOC && DMA_SHARED_BUFFER
help
Allows userspace processes and kernel modules to use Xen backed
dma-buf implementation. With this extension grant references to
the pages of an imported dma-buf can be exported for other domain
use and grant references coming from a foreign domain can be
converted into a local dma-buf for local export.
config XEN_GRANT_DEV_ALLOC
tristate "User-space grant reference allocator driver"
depends on XEN
@ -161,6 +171,20 @@ config XEN_GRANT_DEV_ALLOC
to other domains. This can be used to implement frontend drivers
or as part of an inter-domain shared memory channel.
config XEN_GRANT_DMA_ALLOC
bool "Allow allocating DMA capable buffers with grant reference module"
depends on XEN && HAS_DMA
help
Extends grant table module API to allow allocating DMA capable
buffers and mapping foreign grant references on top of it.
The resulting buffer is similar to one allocated by the balloon
driver in that proper memory reservation is made by
({increase|decrease}_reservation and VA mappings are updated if
needed).
This is useful for sharing foreign buffers with HW drivers which
cannot work with scattered buffers provided by the balloon driver,
but require DMAable memory instead.
config SWIOTLB_XEN
def_bool y
select SWIOTLB

2
drivers/xen/Makefile
View File

@ -2,6 +2,7 @@
obj-$(CONFIG_HOTPLUG_CPU) += cpu_hotplug.o
obj-$(CONFIG_X86) += fallback.o
obj-y += grant-table.o features.o balloon.o manage.o preempt.o time.o
obj-y += mem-reservation.o
obj-y += events/
obj-y += xenbus/
@ -40,5 +41,6 @@ obj-$(CONFIG_XEN_PVCALLS_BACKEND) += pvcalls-back.o
obj-$(CONFIG_XEN_PVCALLS_FRONTEND) += pvcalls-front.o
xen-evtchn-y := evtchn.o
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

75
drivers/xen/balloon.c
View File

@ -71,6 +71,7 @@
#include <xen/balloon.h>
#include <xen/features.h>
#include <xen/page.h>
#include <xen/mem-reservation.h>
static int xen_hotplug_unpopulated;
@ -157,13 +158,6 @@ static DECLARE_DELAYED_WORK(balloon_worker, balloon_process);
#define GFP_BALLOON \
(GFP_HIGHUSER | __GFP_NOWARN | __GFP_NORETRY | __GFP_NOMEMALLOC)
static void scrub_page(struct page *page)
{
#ifdef CONFIG_XEN_SCRUB_PAGES
clear_highpage(page);
#endif
}
/* balloon_append: add the given page to the balloon. */
static void __balloon_append(struct page *page)
{
@ -463,11 +457,6 @@ static enum bp_state increase_reservation(unsigned long nr_pages)
int rc;
unsigned long i;
struct page *page;
struct xen_memory_reservation reservation = {
.address_bits = 0,
.extent_order = EXTENT_ORDER,
.domid = DOMID_SELF
};
if (nr_pages > ARRAY_SIZE(frame_list))
nr_pages = ARRAY_SIZE(frame_list);
@ -479,16 +468,11 @@ static enum bp_state increase_reservation(unsigned long nr_pages)
break;
}
/* XENMEM_populate_physmap requires a PFN based on Xen
* granularity.
*/
frame_list[i] = page_to_xen_pfn(page);
page = balloon_next_page(page);
}
set_xen_guest_handle(reservation.extent_start, frame_list);
reservation.nr_extents = nr_pages;
rc = HYPERVISOR_memory_op(XENMEM_populate_physmap, &reservation);
rc = xenmem_reservation_increase(nr_pages, frame_list);
if (rc <= 0)
return BP_EAGAIN;
@ -496,29 +480,7 @@ static enum bp_state increase_reservation(unsigned long nr_pages)
page = balloon_retrieve(false);
BUG_ON(page == NULL);
#ifdef CONFIG_XEN_HAVE_PVMMU
/*
* We don't support PV MMU when Linux and Xen is using
* different page granularity.
*/
BUILD_BUG_ON(XEN_PAGE_SIZE != PAGE_SIZE);
if (!xen_feature(XENFEAT_auto_translated_physmap)) {
unsigned long pfn = page_to_pfn(page);
set_phys_to_machine(pfn, frame_list[i]);
/* Link back into the page tables if not highmem. */
if (!PageHighMem(page)) {
int ret;
ret = HYPERVISOR_update_va_mapping(
(unsigned long)__va(pfn << PAGE_SHIFT),
mfn_pte(frame_list[i], PAGE_KERNEL),
0);
BUG_ON(ret);
}
}
#endif
xenmem_reservation_va_mapping_update(1, &page, &frame_list[i]);
/* Relinquish the page back to the allocator. */
free_reserved_page(page);
@ -535,11 +497,6 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp)
unsigned long i;
struct page *page, *tmp;
int ret;
struct xen_memory_reservation reservation = {
.address_bits = 0,
.extent_order = EXTENT_ORDER,
.domid = DOMID_SELF
};
LIST_HEAD(pages);
if (nr_pages > ARRAY_SIZE(frame_list))
@ -553,7 +510,7 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp)
break;
}
adjust_managed_page_count(page, -1);
scrub_page(page);
xenmem_reservation_scrub_page(page);
list_add(&page->lru, &pages);
}
@ -572,28 +529,10 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp)
*/
i = 0;
list_for_each_entry_safe(page, tmp, &pages, lru) {
/* XENMEM_decrease_reservation requires a GFN */
frame_list[i++] = xen_page_to_gfn(page);
#ifdef CONFIG_XEN_HAVE_PVMMU
/*
* We don't support PV MMU when Linux and Xen is using
* different page granularity.
*/
BUILD_BUG_ON(XEN_PAGE_SIZE != PAGE_SIZE);
xenmem_reservation_va_mapping_reset(1, &page);
if (!xen_feature(XENFEAT_auto_translated_physmap)) {
unsigned long pfn = page_to_pfn(page);
if (!PageHighMem(page)) {
ret = HYPERVISOR_update_va_mapping(
(unsigned long)__va(pfn << PAGE_SHIFT),
__pte_ma(0), 0);
BUG_ON(ret);
}
__set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
}
#endif
list_del(&page->lru);
balloon_append(page);
@ -601,9 +540,7 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp)
flush_tlb_all();
set_xen_guest_handle(reservation.extent_start, frame_list);
reservation.nr_extents = nr_pages;
ret = HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation);
ret = xenmem_reservation_decrease(nr_pages, frame_list);
BUG_ON(ret != nr_pages);
balloon_stats.current_pages -= nr_pages;

2
drivers/xen/biomerge.c
View File

@ -17,7 +17,7 @@ bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
* XXX: Add support for merging bio_vec when using different page
* size in Xen and Linux.
*/
return 0;
return false;
#endif
}
EXPORT_SYMBOL(xen_biovec_phys_mergeable);

94
drivers/xen/gntdev-common.h Normal file
View File

@ -0,0 +1,94 @@
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Common functionality of grant device.
*
* Copyright (c) 2006-2007, D G Murray.
* (c) 2009 Gerd Hoffmann <kraxel@redhat.com>
* (c) 2018 Oleksandr Andrushchenko, EPAM Systems Inc.
*/
#ifndef _GNTDEV_COMMON_H
#define _GNTDEV_COMMON_H
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/mmu_notifier.h>
#include <linux/types.h>
struct gntdev_dmabuf_priv;
struct gntdev_priv {
/* Maps with visible offsets in the file descriptor. */
struct list_head maps;
/*
* Maps that are not visible; will be freed on munmap.
* Only populated if populate_freeable_maps == 1
*/
struct list_head freeable_maps;
/* lock protects maps and freeable_maps. */
struct mutex lock;
struct mm_struct *mm;
struct mmu_notifier mn;
#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
/* Device for which DMA memory is allocated. */
struct device *dma_dev;
#endif
#ifdef CONFIG_XEN_GNTDEV_DMABUF
struct gntdev_dmabuf_priv *dmabuf_priv;
#endif
};
struct gntdev_unmap_notify {
int flags;
/* Address relative to the start of the gntdev_grant_map. */
int addr;
int event;
};
struct gntdev_grant_map {
struct list_head next;
struct vm_area_struct *vma;
int index;
int count;
int flags;
refcount_t users;
struct gntdev_unmap_notify notify;
struct ioctl_gntdev_grant_ref *grants;
struct gnttab_map_grant_ref *map_ops;
struct gnttab_unmap_grant_ref *unmap_ops;
struct gnttab_map_grant_ref *kmap_ops;
struct gnttab_unmap_grant_ref *kunmap_ops;
struct page **pages;
unsigned long pages_vm_start;
#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
/*
* If dmabuf_vaddr is not NULL then this mapping is backed by DMA
* capable memory.
*/
struct device *dma_dev;
/* Flags used to create this DMA buffer: GNTDEV_DMA_FLAG_XXX. */
int dma_flags;
void *dma_vaddr;
dma_addr_t dma_bus_addr;
/* Needed to avoid allocation in gnttab_dma_free_pages(). */
xen_pfn_t *frames;
#endif
};
struct gntdev_grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count,
int dma_flags);
void gntdev_add_map(struct gntdev_priv *priv, struct gntdev_grant_map *add);
void gntdev_put_map(struct gntdev_priv *priv, struct gntdev_grant_map *map);
bool gntdev_account_mapped_pages(int count);
int gntdev_map_grant_pages(struct gntdev_grant_map *map);
#endif

857
drivers/xen/gntdev-dmabuf.c Normal file
View File

@ -0,0 +1,857 @@
// SPDX-License-Identifier: GPL-2.0
/*
* Xen dma-buf functionality for gntdev.
*
* DMA buffer implementation is based on drivers/gpu/drm/drm_prime.c.
*
* Copyright (c) 2018 Oleksandr Andrushchenko, EPAM Systems Inc.
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/dma-buf.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/uaccess.h>
#include <xen/xen.h>
#include <xen/grant_table.h>
#include "gntdev-common.h"
#include "gntdev-dmabuf.h"
#ifndef GRANT_INVALID_REF
/*
* Note on usage of grant reference 0 as invalid grant reference:
* grant reference 0 is valid, but never exposed to a driver,
* because of the fact it is already in use/reserved by the PV console.
*/
#define GRANT_INVALID_REF 0
#endif
struct gntdev_dmabuf {
struct gntdev_dmabuf_priv *priv;
struct dma_buf *dmabuf;
struct list_head next;
int fd;
union {
struct {
/* Exported buffers are reference counted. */
struct kref refcount;
struct gntdev_priv *priv;
struct gntdev_grant_map *map;
} exp;
struct {
/* Granted references of the imported buffer. */
grant_ref_t *refs;
/* Scatter-gather table of the imported buffer. */
struct sg_table *sgt;
/* dma-buf attachment of the imported buffer. */
struct dma_buf_attachment *attach;
} imp;
} u;
/* Number of pages this buffer has. */
int nr_pages;
/* Pages of this buffer. */
struct page **pages;
};
struct gntdev_dmabuf_wait_obj {
struct list_head next;
struct gntdev_dmabuf *gntdev_dmabuf;
struct completion completion;
};
struct gntdev_dmabuf_attachment {
struct sg_table *sgt;
enum dma_data_direction dir;
};
struct gntdev_dmabuf_priv {
/* List of exported DMA buffers. */
struct list_head exp_list;
/* List of wait objects. */
struct list_head exp_wait_list;
/* List of imported DMA buffers. */
struct list_head imp_list;
/* This is the lock which protects dma_buf_xxx lists. */
struct mutex lock;
};
/* DMA buffer export support. */
/* Implementation of wait for exported DMA buffer to be released. */
static void dmabuf_exp_release(struct kref *kref);
static struct gntdev_dmabuf_wait_obj *
dmabuf_exp_wait_obj_new(struct gntdev_dmabuf_priv *priv,
struct gntdev_dmabuf *gntdev_dmabuf)
{
struct gntdev_dmabuf_wait_obj *obj;
obj = kzalloc(sizeof(*obj), GFP_KERNEL);
if (!obj)
return ERR_PTR(-ENOMEM);
init_completion(&obj->completion);
obj->gntdev_dmabuf = gntdev_dmabuf;
mutex_lock(&priv->lock);
list_add(&obj->next, &priv->exp_wait_list);
/* Put our reference and wait for gntdev_dmabuf's release to fire. */
kref_put(&gntdev_dmabuf->u.exp.refcount, dmabuf_exp_release);
mutex_unlock(&priv->lock);
return obj;
}
static void dmabuf_exp_wait_obj_free(struct gntdev_dmabuf_priv *priv,
struct gntdev_dmabuf_wait_obj *obj)
{
mutex_lock(&priv->lock);
list_del(&obj->next);
mutex_unlock(&priv->lock);
kfree(obj);
}
static int dmabuf_exp_wait_obj_wait(struct gntdev_dmabuf_wait_obj *obj,
u32 wait_to_ms)
{
if (wait_for_completion_timeout(&obj->completion,
msecs_to_jiffies(wait_to_ms)) <= 0)
return -ETIMEDOUT;
return 0;
}
static void dmabuf_exp_wait_obj_signal(struct gntdev_dmabuf_priv *priv,
struct gntdev_dmabuf *gntdev_dmabuf)
{
struct gntdev_dmabuf_wait_obj *obj;
list_for_each_entry(obj, &priv->exp_wait_list, next)
if (obj->gntdev_dmabuf == gntdev_dmabuf) {
pr_debug("Found gntdev_dmabuf in the wait list, wake\n");
complete_all(&obj->completion);
break;
}
}
static struct gntdev_dmabuf *
dmabuf_exp_wait_obj_get_dmabuf(struct gntdev_dmabuf_priv *priv, int fd)
{
struct gntdev_dmabuf *gntdev_dmabuf, *ret = ERR_PTR(-ENOENT);
mutex_lock(&priv->lock);
list_for_each_entry(gntdev_dmabuf, &priv->exp_list, next)
if (gntdev_dmabuf->fd == fd) {
pr_debug("Found gntdev_dmabuf in the wait list\n");
kref_get(&gntdev_dmabuf->u.exp.refcount);
ret = gntdev_dmabuf;
break;
}
mutex_unlock(&priv->lock);
return ret;
}
static int dmabuf_exp_wait_released(struct gntdev_dmabuf_priv *priv, int fd,
int wait_to_ms)
{
struct gntdev_dmabuf *gntdev_dmabuf;
struct gntdev_dmabuf_wait_obj *obj;
int ret;
pr_debug("Will wait for dma-buf with fd %d\n", fd);
/*
* Try to find the DMA buffer: if not found means that
* either the buffer has already been released or file descriptor
* provided is wrong.
*/
gntdev_dmabuf = dmabuf_exp_wait_obj_get_dmabuf(priv, fd);
if (IS_ERR(gntdev_dmabuf))
return PTR_ERR(gntdev_dmabuf);
/*
* gntdev_dmabuf still exists and is reference count locked by us now,
* so prepare to wait: allocate wait object and add it to the wait list,
* so we can find it on release.
*/
obj = dmabuf_exp_wait_obj_new(priv, gntdev_dmabuf);
if (IS_ERR(obj))
return PTR_ERR(obj);
ret = dmabuf_exp_wait_obj_wait(obj, wait_to_ms);
dmabuf_exp_wait_obj_free(priv, obj);
return ret;
}
/* DMA buffer export support. */
static struct sg_table *
dmabuf_pages_to_sgt(struct page **pages, unsigned int nr_pages)
{
struct sg_table *sgt;
int ret;
sgt = kmalloc(sizeof(*sgt), GFP_KERNEL);
if (!sgt) {
ret = -ENOMEM;
goto out;
}
ret = sg_alloc_table_from_pages(sgt, pages, nr_pages, 0,
nr_pages << PAGE_SHIFT,
GFP_KERNEL);
if (ret)
goto out;
return sgt;
out:
kfree(sgt);
return ERR_PTR(ret);
}
static int dmabuf_exp_ops_attach(struct dma_buf *dma_buf,
struct device *target_dev,
struct dma_buf_attachment *attach)
{
struct gntdev_dmabuf_attachment *gntdev_dmabuf_attach;
gntdev_dmabuf_attach = kzalloc(sizeof(*gntdev_dmabuf_attach),
GFP_KERNEL);
if (!gntdev_dmabuf_attach)
return -ENOMEM;
gntdev_dmabuf_attach->dir = DMA_NONE;
attach->priv = gntdev_dmabuf_attach;
return 0;
}
static void dmabuf_exp_ops_detach(struct dma_buf *dma_buf,
struct dma_buf_attachment *attach)
{
struct gntdev_dmabuf_attachment *gntdev_dmabuf_attach = attach->priv;
if (gntdev_dmabuf_attach) {
struct sg_table *sgt = gntdev_dmabuf_attach->sgt;
if (sgt) {
if (gntdev_dmabuf_attach->dir != DMA_NONE)
dma_unmap_sg_attrs(attach->dev, sgt->sgl,
sgt->nents,
gntdev_dmabuf_attach->dir,
DMA_ATTR_SKIP_CPU_SYNC);
sg_free_table(sgt);
}
kfree(sgt);
kfree(gntdev_dmabuf_attach);
attach->priv = NULL;
}
}
static struct sg_table *
dmabuf_exp_ops_map_dma_buf(struct dma_buf_attachment *attach,
enum dma_data_direction dir)
{
struct gntdev_dmabuf_attachment *gntdev_dmabuf_attach = attach->priv;
struct gntdev_dmabuf *gntdev_dmabuf = attach->dmabuf->priv;
struct sg_table *sgt;
pr_debug("Mapping %d pages for dev %p\n", gntdev_dmabuf->nr_pages,
attach->dev);
if (dir == DMA_NONE || !gntdev_dmabuf_attach)
return ERR_PTR(-EINVAL);
/* Return the cached mapping when possible. */
if (gntdev_dmabuf_attach->dir == dir)
return gntdev_dmabuf_attach->sgt;
/*
* Two mappings with different directions for the same attachment are
* not allowed.
*/
if (gntdev_dmabuf_attach->dir != DMA_NONE)
return ERR_PTR(-EBUSY);
sgt = dmabuf_pages_to_sgt(gntdev_dmabuf->pages,
gntdev_dmabuf->nr_pages);
if (!IS_ERR(sgt)) {
if (!dma_map_sg_attrs(attach->dev, sgt->sgl, sgt->nents, dir,
DMA_ATTR_SKIP_CPU_SYNC)) {
sg_free_table(sgt);
kfree(sgt);
sgt = ERR_PTR(-ENOMEM);
} else {
gntdev_dmabuf_attach->sgt = sgt;
gntdev_dmabuf_attach->dir = dir;
}
}
if (IS_ERR(sgt))
pr_debug("Failed to map sg table for dev %p\n", attach->dev);
return sgt;
}
static void dmabuf_exp_ops_unmap_dma_buf(struct dma_buf_attachment *attach,
struct sg_table *sgt,
enum dma_data_direction dir)
{
/* Not implemented. The unmap is done at dmabuf_exp_ops_detach(). */
}
static void dmabuf_exp_release(struct kref *kref)
{
struct gntdev_dmabuf *gntdev_dmabuf =
container_of(kref, struct gntdev_dmabuf, u.exp.refcount);
dmabuf_exp_wait_obj_signal(gntdev_dmabuf->priv, gntdev_dmabuf);
list_del(&gntdev_dmabuf->next);
kfree(gntdev_dmabuf);
}
static void dmabuf_exp_remove_map(struct gntdev_priv *priv,
struct gntdev_grant_map *map)
{
mutex_lock(&priv->lock);
list_del(&map->next);
gntdev_put_map(NULL /* already removed */, map);
mutex_unlock(&priv->lock);
}
static void dmabuf_exp_ops_release(struct dma_buf *dma_buf)
{
struct gntdev_dmabuf *gntdev_dmabuf = dma_buf->priv;
struct gntdev_dmabuf_priv *priv = gntdev_dmabuf->priv;
dmabuf_exp_remove_map(gntdev_dmabuf->u.exp.priv,
gntdev_dmabuf->u.exp.map);
mutex_lock(&priv->lock);
kref_put(&gntdev_dmabuf->u.exp.refcount, dmabuf_exp_release);
mutex_unlock(&priv->lock);
}
static void *dmabuf_exp_ops_kmap(struct dma_buf *dma_buf,
unsigned long page_num)
{
/* Not implemented. */
return NULL;
}
static void dmabuf_exp_ops_kunmap(struct dma_buf *dma_buf,
unsigned long page_num, void *addr)
{
/* Not implemented. */
}
static int dmabuf_exp_ops_mmap(struct dma_buf *dma_buf,
struct vm_area_struct *vma)
{
/* Not implemented. */
return 0;
}
static const struct dma_buf_ops dmabuf_exp_ops = {
.attach = dmabuf_exp_ops_attach,
.detach = dmabuf_exp_ops_detach,
.map_dma_buf = dmabuf_exp_ops_map_dma_buf,
.unmap_dma_buf = dmabuf_exp_ops_unmap_dma_buf,
.release = dmabuf_exp_ops_release,
.map = dmabuf_exp_ops_kmap,
.unmap = dmabuf_exp_ops_kunmap,
.mmap = dmabuf_exp_ops_mmap,
};
struct gntdev_dmabuf_export_args {
struct gntdev_priv *priv;
struct gntdev_grant_map *map;
struct gntdev_dmabuf_priv *dmabuf_priv;
struct device *dev;
int count;
struct page **pages;
u32 fd;
};
static int dmabuf_exp_from_pages(struct gntdev_dmabuf_export_args *args)
{
DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
struct gntdev_dmabuf *gntdev_dmabuf;
int ret;
gntdev_dmabuf = kzalloc(sizeof(*gntdev_dmabuf), GFP_KERNEL);
if (!gntdev_dmabuf)
return -ENOMEM;
kref_init(&gntdev_dmabuf->u.exp.refcount);
gntdev_dmabuf->priv = args->dmabuf_priv;
gntdev_dmabuf->nr_pages = args->count;
gntdev_dmabuf->pages = args->pages;
gntdev_dmabuf->u.exp.priv = args->priv;
gntdev_dmabuf->u.exp.map = args->map;
exp_info.exp_name = KBUILD_MODNAME;
if (args->dev->driver && args->dev->driver->owner)
exp_info.owner = args->dev->driver->owner;
else
exp_info.owner = THIS_MODULE;
exp_info.ops = &dmabuf_exp_ops;
exp_info.size = args->count << PAGE_SHIFT;
exp_info.flags = O_RDWR;
exp_info.priv = gntdev_dmabuf;
gntdev_dmabuf->dmabuf = dma_buf_export(&exp_info);
if (IS_ERR(gntdev_dmabuf->dmabuf)) {
ret = PTR_ERR(gntdev_dmabuf->dmabuf);
gntdev_dmabuf->dmabuf = NULL;
goto fail;
}
ret = dma_buf_fd(gntdev_dmabuf->dmabuf, O_CLOEXEC);
if (ret < 0)
goto fail;
gntdev_dmabuf->fd = ret;
args->fd = ret;
pr_debug("Exporting DMA buffer with fd %d\n", ret);
mutex_lock(&args->dmabuf_priv->lock);
list_add(&gntdev_dmabuf->next, &args->dmabuf_priv->exp_list);
mutex_unlock(&args->dmabuf_priv->lock);
return 0;
fail:
if (gntdev_dmabuf->dmabuf)
dma_buf_put(gntdev_dmabuf->dmabuf);
kfree(gntdev_dmabuf);
return ret;
}
static struct gntdev_grant_map *
dmabuf_exp_alloc_backing_storage(struct gntdev_priv *priv, int dmabuf_flags,
int count)
{
struct gntdev_grant_map *map;
if (unlikely(count <= 0))
return ERR_PTR(-EINVAL);
if ((dmabuf_flags & GNTDEV_DMA_FLAG_WC) &&
(dmabuf_flags & GNTDEV_DMA_FLAG_COHERENT)) {
pr_debug("Wrong dma-buf flags: 0x%x\n", dmabuf_flags);
return ERR_PTR(-EINVAL);
}
map = gntdev_alloc_map(priv, count, dmabuf_flags);
if (!map)
return ERR_PTR(-ENOMEM);
if (unlikely(gntdev_account_mapped_pages(count))) {
pr_debug("can't map %d pages: over limit\n", count);
gntdev_put_map(NULL, map);
return ERR_PTR(-ENOMEM);
}
return map;
}
static int dmabuf_exp_from_refs(struct gntdev_priv *priv, int flags,
int count, u32 domid, u32 *refs, u32 *fd)
{
struct gntdev_grant_map *map;
struct gntdev_dmabuf_export_args args;
int i, ret;
map = dmabuf_exp_alloc_backing_storage(priv, flags, count);
if (IS_ERR(map))
return PTR_ERR(map);
for (i = 0; i < count; i++) {
map->grants[i].domid = domid;
map->grants[i].ref = refs[i];
}
mutex_lock(&priv->lock);
gntdev_add_map(priv, map);
mutex_unlock(&priv->lock);
map->flags |= GNTMAP_host_map;
#if defined(CONFIG_X86)
map->flags |= GNTMAP_device_map;
#endif
ret = gntdev_map_grant_pages(map);
if (ret < 0)
goto out;
args.priv = priv;
args.map = map;
args.dev = priv->dma_dev;
args.dmabuf_priv = priv->dmabuf_priv;
args.count = map->count;
args.pages = map->pages;
args.fd = -1; /* Shut up unnecessary gcc warning for i386 */
ret = dmabuf_exp_from_pages(&args);
if (ret < 0)
goto out;
*fd = args.fd;
return 0;
out:
dmabuf_exp_remove_map(priv, map);
return ret;
}
/* DMA buffer import support. */
static int
dmabuf_imp_grant_foreign_access(struct page **pages, u32 *refs,
int count, int domid)
{
grant_ref_t priv_gref_head;
int i, ret;
ret = gnttab_alloc_grant_references(count, &priv_gref_head);
if (ret < 0) {
pr_debug("Cannot allocate grant references, ret %d\n", ret);
return ret;
}
for (i = 0; i < count; i++) {
int cur_ref;
cur_ref = gnttab_claim_grant_reference(&priv_gref_head);
if (cur_ref < 0) {
ret = cur_ref;
pr_debug("Cannot claim grant reference, ret %d\n", ret);
goto out;
}
gnttab_grant_foreign_access_ref(cur_ref, domid,
xen_page_to_gfn(pages[i]), 0);
refs[i] = cur_ref;
}
return 0;
out:
gnttab_free_grant_references(priv_gref_head);
return ret;
}
static void dmabuf_imp_end_foreign_access(u32 *refs, int count)
{
int i;
for (i = 0; i < count; i++)
if (refs[i] != GRANT_INVALID_REF)
gnttab_end_foreign_access(refs[i], 0, 0UL);
}
static void dmabuf_imp_free_storage(struct gntdev_dmabuf *gntdev_dmabuf)
{
kfree(gntdev_dmabuf->pages);
kfree(gntdev_dmabuf->u.imp.refs);
kfree(gntdev_dmabuf);
}
static struct gntdev_dmabuf *dmabuf_imp_alloc_storage(int count)
{
struct gntdev_dmabuf *gntdev_dmabuf;
int i;
gntdev_dmabuf = kzalloc(sizeof(*gntdev_dmabuf), GFP_KERNEL);
if (!gntdev_dmabuf)
goto fail_no_free;
gntdev_dmabuf->u.imp.refs = kcalloc(count,
sizeof(gntdev_dmabuf->u.imp.refs[0]),
GFP_KERNEL);
if (!gntdev_dmabuf->u.imp.refs)
goto fail;
gntdev_dmabuf->pages = kcalloc(count,
sizeof(gntdev_dmabuf->pages[0]),
GFP_KERNEL);
if (!gntdev_dmabuf->pages)
goto fail;
gntdev_dmabuf->nr_pages = count;
for (i = 0; i < count; i++)
gntdev_dmabuf->u.imp.refs[i] = GRANT_INVALID_REF;
return gntdev_dmabuf;
fail:
dmabuf_imp_free_storage(gntdev_dmabuf);
fail_no_free:
return ERR_PTR(-ENOMEM);
}
static struct gntdev_dmabuf *
dmabuf_imp_to_refs(struct gntdev_dmabuf_priv *priv, struct device *dev,
int fd, int count, int domid)
{
struct gntdev_dmabuf *gntdev_dmabuf, *ret;
struct dma_buf *dma_buf;
struct dma_buf_attachment *attach;
struct sg_table *sgt;
struct sg_page_iter sg_iter;
int i;
dma_buf = dma_buf_get(fd);
if (IS_ERR(dma_buf))
return ERR_CAST(dma_buf);
gntdev_dmabuf = dmabuf_imp_alloc_storage(count);
if (IS_ERR(gntdev_dmabuf)) {
ret = gntdev_dmabuf;
goto fail_put;
}
gntdev_dmabuf->priv = priv;
gntdev_dmabuf->fd = fd;
attach = dma_buf_attach(dma_buf, dev);
if (IS_ERR(attach)) {
ret = ERR_CAST(attach);
goto fail_free_obj;
}
gntdev_dmabuf->u.imp.attach = attach;
sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL);
if (IS_ERR(sgt)) {
ret = ERR_CAST(sgt);
goto fail_detach;
}
/* Check number of pages that imported buffer has. */
if (attach->dmabuf->size != gntdev_dmabuf->nr_pages << PAGE_SHIFT) {
ret = ERR_PTR(-EINVAL);
pr_debug("DMA buffer has %zu pages, user-space expects %d\n",
attach->dmabuf->size, gntdev_dmabuf->nr_pages);
goto fail_unmap;
}
gntdev_dmabuf->u.imp.sgt = sgt;
/* Now convert sgt to array of pages and check for page validity. */
i = 0;
for_each_sg_page(sgt->sgl, &sg_iter, sgt->nents, 0) {
struct page *page = sg_page_iter_page(&sg_iter);
/*
* Check if page is valid: this can happen if we are given
* a page from VRAM or other resources which are not backed
* by a struct page.
*/
if (!pfn_valid(page_to_pfn(page))) {
ret = ERR_PTR(-EINVAL);
goto fail_unmap;
}
gntdev_dmabuf->pages[i++] = page;
}
ret = ERR_PTR(dmabuf_imp_grant_foreign_access(gntdev_dmabuf->pages,
gntdev_dmabuf->u.imp.refs,
count, domid));
if (IS_ERR(ret))
goto fail_end_access;
pr_debug("Imported DMA buffer with fd %d\n", fd);
mutex_lock(&priv->lock);
list_add(&gntdev_dmabuf->next, &priv->imp_list);
mutex_unlock(&priv->lock);
return gntdev_dmabuf;
fail_end_access:
dmabuf_imp_end_foreign_access(gntdev_dmabuf->u.imp.refs, count);
fail_unmap:
dma_buf_unmap_attachment(attach, sgt, DMA_BIDIRECTIONAL);
fail_detach:
dma_buf_detach(dma_buf, attach);
fail_free_obj:
dmabuf_imp_free_storage(gntdev_dmabuf);
fail_put:
dma_buf_put(dma_buf);
return ret;
}
/*
* Find the hyper dma-buf by its file descriptor and remove
* it from the buffer's list.
*/
static struct gntdev_dmabuf *
dmabuf_imp_find_unlink(struct gntdev_dmabuf_priv *priv, int fd)
{
struct gntdev_dmabuf *q, *gntdev_dmabuf, *ret = ERR_PTR(-ENOENT);
mutex_lock(&priv->lock);
list_for_each_entry_safe(gntdev_dmabuf, q, &priv->imp_list, next) {
if (gntdev_dmabuf->fd == fd) {
pr_debug("Found gntdev_dmabuf in the import list\n");
ret = gntdev_dmabuf;
list_del(&gntdev_dmabuf->next);
break;
}
}
mutex_unlock(&priv->lock);
return ret;
}
static int dmabuf_imp_release(struct gntdev_dmabuf_priv *priv, u32 fd)
{
struct gntdev_dmabuf *gntdev_dmabuf;
struct dma_buf_attachment *attach;
struct dma_buf *dma_buf;
gntdev_dmabuf = dmabuf_imp_find_unlink(priv, fd);
if (IS_ERR(gntdev_dmabuf))
return PTR_ERR(gntdev_dmabuf);
pr_debug("Releasing DMA buffer with fd %d\n", fd);
dmabuf_imp_end_foreign_access(gntdev_dmabuf->u.imp.refs,
gntdev_dmabuf->nr_pages);
attach = gntdev_dmabuf->u.imp.attach;
if (gntdev_dmabuf->u.imp.sgt)
dma_buf_unmap_attachment(attach, gntdev_dmabuf->u.imp.sgt,
DMA_BIDIRECTIONAL);
dma_buf = attach->dmabuf;
dma_buf_detach(attach->dmabuf, attach);
dma_buf_put(dma_buf);
dmabuf_imp_free_storage(gntdev_dmabuf);
return 0;
}
/* DMA buffer IOCTL support. */
long gntdev_ioctl_dmabuf_exp_from_refs(struct gntdev_priv *priv, int use_ptemod,
struct ioctl_gntdev_dmabuf_exp_from_refs __user *u)
{
struct ioctl_gntdev_dmabuf_exp_from_refs op;
u32 *refs;
long ret;
if (use_ptemod) {
pr_debug("Cannot provide dma-buf: use_ptemode %d\n",
use_ptemod);
return -EINVAL;
}
if (copy_from_user(&op, u, sizeof(op)) != 0)
return -EFAULT;
if (unlikely(op.count <= 0))
return -EINVAL;
refs = kcalloc(op.count, sizeof(*refs), GFP_KERNEL);
if (!refs)
return -ENOMEM;
if (copy_from_user(refs, u->refs, sizeof(*refs) * op.count) != 0) {
ret = -EFAULT;
goto out;
}
ret = dmabuf_exp_from_refs(priv, op.flags, op.count,
op.domid, refs, &op.fd);
if (ret)
goto out;
if (copy_to_user(u, &op, sizeof(op)) != 0)
ret = -EFAULT;
out:
kfree(refs);
return ret;
}
long gntdev_ioctl_dmabuf_exp_wait_released(struct gntdev_priv *priv,
struct ioctl_gntdev_dmabuf_exp_wait_released __user *u)
{
struct ioctl_gntdev_dmabuf_exp_wait_released op;
if (copy_from_user(&op, u, sizeof(op)) != 0)
return -EFAULT;
return dmabuf_exp_wait_released(priv->dmabuf_priv, op.fd,
op.wait_to_ms);
}
long gntdev_ioctl_dmabuf_imp_to_refs(struct gntdev_priv *priv,
struct ioctl_gntdev_dmabuf_imp_to_refs __user *u)
{
struct ioctl_gntdev_dmabuf_imp_to_refs op;
struct gntdev_dmabuf *gntdev_dmabuf;
long ret;
if (copy_from_user(&op, u, sizeof(op)) != 0)
return -EFAULT;
if (unlikely(op.count <= 0))
return -EINVAL;
gntdev_dmabuf = dmabuf_imp_to_refs(priv->dmabuf_priv,
priv->dma_dev, op.fd,
op.count, op.domid);
if (IS_ERR(gntdev_dmabuf))
return PTR_ERR(gntdev_dmabuf);
if (copy_to_user(u->refs, gntdev_dmabuf->u.imp.refs,
sizeof(*u->refs) * op.count) != 0) {
ret = -EFAULT;
goto out_release;
}
return 0;
out_release:
dmabuf_imp_release(priv->dmabuf_priv, op.fd);
return ret;
}
long gntdev_ioctl_dmabuf_imp_release(struct gntdev_priv *priv,
struct ioctl_gntdev_dmabuf_imp_release __user *u)
{
struct ioctl_gntdev_dmabuf_imp_release op;
if (copy_from_user(&op, u, sizeof(op)) != 0)
return -EFAULT;
return dmabuf_imp_release(priv->dmabuf_priv, op.fd);
}
struct gntdev_dmabuf_priv *gntdev_dmabuf_init(void)
{
struct gntdev_dmabuf_priv *priv;
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv)
return ERR_PTR(-ENOMEM);
mutex_init(&priv->lock);
INIT_LIST_HEAD(&priv->exp_list);
INIT_LIST_HEAD(&priv->exp_wait_list);
INIT_LIST_HEAD(&priv->imp_list);
return priv;
}
void gntdev_dmabuf_fini(struct gntdev_dmabuf_priv *priv)
{
kfree(priv);
}

33
drivers/xen/gntdev-dmabuf.h Normal file
View File

@ -0,0 +1,33 @@
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Xen dma-buf functionality for gntdev.
*
* Copyright (c) 2018 Oleksandr Andrushchenko, EPAM Systems Inc.
*/
#ifndef _GNTDEV_DMABUF_H
#define _GNTDEV_DMABUF_H
#include <xen/gntdev.h>
struct gntdev_dmabuf_priv;
struct gntdev_priv;
struct gntdev_dmabuf_priv *gntdev_dmabuf_init(void);
void gntdev_dmabuf_fini(struct gntdev_dmabuf_priv *priv);
long gntdev_ioctl_dmabuf_exp_from_refs(struct gntdev_priv *priv, int use_ptemod,
struct ioctl_gntdev_dmabuf_exp_from_refs __user *u);
long gntdev_ioctl_dmabuf_exp_wait_released(struct gntdev_priv *priv,
struct ioctl_gntdev_dmabuf_exp_wait_released __user *u);
long gntdev_ioctl_dmabuf_imp_to_refs(struct gntdev_priv *priv,
struct ioctl_gntdev_dmabuf_imp_to_refs __user *u);
long gntdev_ioctl_dmabuf_imp_release(struct gntdev_priv *priv,
struct ioctl_gntdev_dmabuf_imp_release __user *u);
#endif

220
drivers/xen/gntdev.c
View File

@ -6,6 +6,7 @@
*
* Copyright (c) 2006-2007, D G Murray.
* (c) 2009 Gerd Hoffmann <kraxel@redhat.com>
* (c) 2018 Oleksandr Andrushchenko, EPAM Systems Inc.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
@ -26,10 +27,6 @@
#include <linux/init.h>
#include <linux/miscdevice.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/mmu_notifier.h>
#include <linux/types.h>
#include <linux/uaccess.h>
#include <linux/sched.h>
#include <linux/sched/mm.h>
@ -37,6 +34,9 @@
#include <linux/slab.h>
#include <linux/highmem.h>
#include <linux/refcount.h>
#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
#include <linux/of_device.h>
#endif
#include <xen/xen.h>
#include <xen/grant_table.h>
@ -47,6 +47,11 @@
#include <asm/xen/hypervisor.h>
#include <asm/xen/hypercall.h>
#include "gntdev-common.h"
#ifdef CONFIG_XEN_GNTDEV_DMABUF
#include "gntdev-dmabuf.h"
#endif
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Derek G. Murray <Derek.Murray@cl.cam.ac.uk>, "
"Gerd Hoffmann <kraxel@redhat.com>");
@ -62,51 +67,23 @@ static atomic_t pages_mapped = ATOMIC_INIT(0);
static int use_ptemod;
#define populate_freeable_maps use_ptemod
struct gntdev_priv {
/* maps with visible offsets in the file descriptor */
struct list_head maps;
/* maps that are not visible; will be freed on munmap.
* Only populated if populate_freeable_maps == 1 */
struct list_head freeable_maps;
/* lock protects maps and freeable_maps */
struct mutex lock;
struct mm_struct *mm;
struct mmu_notifier mn;
};
static int unmap_grant_pages(struct gntdev_grant_map *map,
int offset, int pages);
struct unmap_notify {
int flags;
/* Address relative to the start of the grant_map */
int addr;
int event;
};
struct grant_map {
struct list_head next;
struct vm_area_struct *vma;
int index;
int count;
int flags;
refcount_t users;
struct unmap_notify notify;
struct ioctl_gntdev_grant_ref *grants;
struct gnttab_map_grant_ref *map_ops;
struct gnttab_unmap_grant_ref *unmap_ops;
struct gnttab_map_grant_ref *kmap_ops;
struct gnttab_unmap_grant_ref *kunmap_ops;
struct page **pages;
unsigned long pages_vm_start;
};
static int unmap_grant_pages(struct grant_map *map, int offset, int pages);
static struct miscdevice gntdev_miscdev;
/* ------------------------------------------------------------------ */
bool gntdev_account_mapped_pages(int count)
{
return atomic_add_return(count, &pages_mapped) > limit;
}
static void gntdev_print_maps(struct gntdev_priv *priv,
char *text, int text_index)
{
#ifdef DEBUG
struct grant_map *map;
struct gntdev_grant_map *map;
pr_debug("%s: maps list (priv %p)\n", __func__, priv);
list_for_each_entry(map, &priv->maps, next)
@ -116,13 +93,32 @@ static void gntdev_print_maps(struct gntdev_priv *priv,
#endif
}
static void gntdev_free_map(struct grant_map *map)
static void gntdev_free_map(struct gntdev_grant_map *map)
{
if (map == NULL)
return;
#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
if (map->dma_vaddr) {
struct gnttab_dma_alloc_args args;
args.dev = map->dma_dev;
args.coherent = !!(map->dma_flags & GNTDEV_DMA_FLAG_COHERENT);
args.nr_pages = map->count;
args.pages = map->pages;
args.frames = map->frames;
args.vaddr = map->dma_vaddr;
args.dev_bus_addr = map->dma_bus_addr;
gnttab_dma_free_pages(&args);
} else
#endif
if (map->pages)
gnttab_free_pages(map->count, map->pages);
#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
kfree(map->frames);
#endif
kfree(map->pages);
kfree(map->grants);
kfree(map->map_ops);
@ -132,12 +128,13 @@ static void gntdev_free_map(struct grant_map *map)
kfree(map);
}
static struct grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count)
struct gntdev_grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count,
int dma_flags)
{
struct grant_map *add;
struct gntdev_grant_map *add;
int i;
add = kzalloc(sizeof(struct grant_map), GFP_KERNEL);
add = kzalloc(sizeof(*add), GFP_KERNEL);
if (NULL == add)
return NULL;
@ -155,6 +152,37 @@ static struct grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count)
NULL == add->pages)
goto err;
#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
add->dma_flags = dma_flags;
/*
* Check if this mapping is requested to be backed
* by a DMA buffer.
*/
if (dma_flags & (GNTDEV_DMA_FLAG_WC | GNTDEV_DMA_FLAG_COHERENT)) {
struct gnttab_dma_alloc_args args;
add->frames = kcalloc(count, sizeof(add->frames[0]),
GFP_KERNEL);
if (!add->frames)
goto err;
/* Remember the device, so we can free DMA memory. */
add->dma_dev = priv->dma_dev;
args.dev = priv->dma_dev;
args.coherent = !!(dma_flags & GNTDEV_DMA_FLAG_COHERENT);
args.nr_pages = count;
args.pages = add->pages;
args.frames = add->frames;
if (gnttab_dma_alloc_pages(&args))
goto err;
add->dma_vaddr = args.vaddr;
add->dma_bus_addr = args.dev_bus_addr;
} else
#endif
if (gnttab_alloc_pages(count, add->pages))
goto err;
@ -176,9 +204,9 @@ err:
return NULL;
}
static void gntdev_add_map(struct gntdev_priv *priv, struct grant_map *add)
void gntdev_add_map(struct gntdev_priv *priv, struct gntdev_grant_map *add)
{
struct grant_map *map;
struct gntdev_grant_map *map;
list_for_each_entry(map, &priv->maps, next) {
if (add->index + add->count < map->index) {
@ -193,10 +221,10 @@ done:
gntdev_print_maps(priv, "[new]", add->index);
}
static struct grant_map *gntdev_find_map_index(struct gntdev_priv *priv,
int index, int count)
static struct gntdev_grant_map *gntdev_find_map_index(struct gntdev_priv *priv,
int index, int count)
{
struct grant_map *map;
struct gntdev_grant_map *map;
list_for_each_entry(map, &priv->maps, next) {
if (map->index != index)
@ -208,7 +236,7 @@ static struct grant_map *gntdev_find_map_index(struct gntdev_priv *priv,
return NULL;
}
static void gntdev_put_map(struct gntdev_priv *priv, struct grant_map *map)
void gntdev_put_map(struct gntdev_priv *priv, struct gntdev_grant_map *map)
{
if (!map)
return;
@ -239,7 +267,7 @@ static void gntdev_put_map(struct gntdev_priv *priv, struct grant_map *map)
static int find_grant_ptes(pte_t *pte, pgtable_t token,
unsigned long addr, void *data)
{
struct grant_map *map = data;
struct gntdev_grant_map *map = data;
unsigned int pgnr = (addr - map->vma->vm_start) >> PAGE_SHIFT;
int flags = map->flags | GNTMAP_application_map | GNTMAP_contains_pte;
u64 pte_maddr;
@ -272,7 +300,7 @@ static int set_grant_ptes_as_special(pte_t *pte, pgtable_t token,
}
#endif
static int map_grant_pages(struct grant_map *map)
int gntdev_map_grant_pages(struct gntdev_grant_map *map)
{
int i, err = 0;
@ -325,11 +353,20 @@ static int map_grant_pages(struct grant_map *map)
map->unmap_ops[i].handle = map->map_ops[i].handle;
if (use_ptemod)
map->kunmap_ops[i].handle = map->kmap_ops[i].handle;
#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
else if (map->dma_vaddr) {
unsigned long bfn;
bfn = pfn_to_bfn(page_to_pfn(map->pages[i]));
map->unmap_ops[i].dev_bus_addr = __pfn_to_phys(bfn);
}
#endif
}
return err;
}
static int __unmap_grant_pages(struct grant_map *map, int offset, int pages)
static int __unmap_grant_pages(struct gntdev_grant_map *map, int offset,
int pages)
{
int i, err = 0;
struct gntab_unmap_queue_data unmap_data;
@ -364,7 +401,8 @@ static int __unmap_grant_pages(struct grant_map *map, int offset, int pages)
return err;
}
static int unmap_grant_pages(struct grant_map *map, int offset, int pages)
static int unmap_grant_pages(struct gntdev_grant_map *map, int offset,
int pages)
{
int range, err = 0;
@ -396,7 +434,7 @@ static int unmap_grant_pages(struct grant_map *map, int offset, int pages)
static void gntdev_vma_open(struct vm_area_struct *vma)
{
struct grant_map *map = vma->vm_private_data;
struct gntdev_grant_map *map = vma->vm_private_data;
pr_debug("gntdev_vma_open %p\n", vma);
refcount_inc(&map->users);
@ -404,7 +442,7 @@ static void gntdev_vma_open(struct vm_area_struct *vma)
static void gntdev_vma_close(struct vm_area_struct *vma)
{
struct grant_map *map = vma->vm_private_data;
struct gntdev_grant_map *map = vma->vm_private_data;
struct file *file = vma->vm_file;
struct gntdev_priv *priv = file->private_data;
@ -428,7 +466,7 @@ static void gntdev_vma_close(struct vm_area_struct *vma)
static struct page *gntdev_vma_find_special_page(struct vm_area_struct *vma,
unsigned long addr)
{
struct grant_map *map = vma->vm_private_data;
struct gntdev_grant_map *map = vma->vm_private_data;
return map->pages[(addr - map->pages_vm_start) >> PAGE_SHIFT];
}
@ -441,7 +479,7 @@ static const struct vm_operations_struct gntdev_vmops = {
/* ------------------------------------------------------------------ */
static void unmap_if_in_range(struct grant_map *map,
static void unmap_if_in_range(struct gntdev_grant_map *map,
unsigned long start, unsigned long end)
{
unsigned long mstart, mend;
@ -470,7 +508,7 @@ static void mn_invl_range_start(struct mmu_notifier *mn,
unsigned long start, unsigned long end)
{
struct gntdev_priv *priv = container_of(mn, struct gntdev_priv, mn);
struct grant_map *map;
struct gntdev_grant_map *map;
mutex_lock(&priv->lock);
list_for_each_entry(map, &priv->maps, next) {
@ -486,7 +524,7 @@ static void mn_release(struct mmu_notifier *mn,
struct mm_struct *mm)
{
struct gntdev_priv *priv = container_of(mn, struct gntdev_priv, mn);
struct grant_map *map;
struct gntdev_grant_map *map;
int err;
mutex_lock(&priv->lock);
@ -531,6 +569,15 @@ static int gntdev_open(struct inode *inode, struct file *flip)
INIT_LIST_HEAD(&priv->freeable_maps);
mutex_init(&priv->lock);
#ifdef CONFIG_XEN_GNTDEV_DMABUF
priv->dmabuf_priv = gntdev_dmabuf_init();
if (IS_ERR(priv->dmabuf_priv)) {
ret = PTR_ERR(priv->dmabuf_priv);
kfree(priv);
return ret;
}
#endif
if (use_ptemod) {
priv->mm = get_task_mm(current);
if (!priv->mm) {
@ -548,6 +595,17 @@ static int gntdev_open(struct inode *inode, struct file *flip)
}
flip->private_data = priv;
#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
priv->dma_dev = gntdev_miscdev.this_device;
/*
* The device is not spawn from a device tree, so arch_setup_dma_ops
* is not called, thus leaving the device with dummy DMA ops.
* Fix this by calling of_dma_configure() with a NULL node to set
* default DMA ops.
*/
of_dma_configure(priv->dma_dev, NULL, true);
#endif
pr_debug("priv %p\n", priv);
return 0;
@ -556,21 +614,27 @@ static int gntdev_open(struct inode *inode, struct file *flip)
static int gntdev_release(struct inode *inode, struct file *flip)
{
struct gntdev_priv *priv = flip->private_data;
struct grant_map *map;
struct gntdev_grant_map *map;
pr_debug("priv %p\n", priv);
mutex_lock(&priv->lock);
while (!list_empty(&priv->maps)) {
map = list_entry(priv->maps.next, struct grant_map, next);
map = list_entry(priv->maps.next,
struct gntdev_grant_map, next);
list_del(&map->next);
gntdev_put_map(NULL /* already removed */, map);
}
WARN_ON(!list_empty(&priv->freeable_maps));
mutex_unlock(&priv->lock);
#ifdef CONFIG_XEN_GNTDEV_DMABUF
gntdev_dmabuf_fini(priv->dmabuf_priv);
#endif
if (use_ptemod)
mmu_notifier_unregister(&priv->mn, priv->mm);
kfree(priv);
return 0;
}
@ -579,7 +643,7 @@ static long gntdev_ioctl_map_grant_ref(struct gntdev_priv *priv,
struct ioctl_gntdev_map_grant_ref __user *u)
{
struct ioctl_gntdev_map_grant_ref op;
struct grant_map *map;
struct gntdev_grant_map *map;
int err;
if (copy_from_user(&op, u, sizeof(op)) != 0)
@ -589,11 +653,11 @@ static long gntdev_ioctl_map_grant_ref(struct gntdev_priv *priv,
return -EINVAL;
err = -ENOMEM;
map = gntdev_alloc_map(priv, op.count);
map = gntdev_alloc_map(priv, op.count, 0 /* This is not a dma-buf. */);
if (!map)
return err;
if (unlikely(atomic_add_return(op.count, &pages_mapped) > limit)) {
if (unlikely(gntdev_account_mapped_pages(op.count))) {
pr_debug("can't map: over limit\n");
gntdev_put_map(NULL, map);
return err;
@ -620,7 +684,7 @@ static long gntdev_ioctl_unmap_grant_ref(struct gntdev_priv *priv,
struct ioctl_gntdev_unmap_grant_ref __user *u)
{
struct ioctl_gntdev_unmap_grant_ref op;
struct grant_map *map;
struct gntdev_grant_map *map;
int err = -ENOENT;
if (copy_from_user(&op, u, sizeof(op)) != 0)
@ -646,7 +710,7 @@ static long gntdev_ioctl_get_offset_for_vaddr(struct gntdev_priv *priv,
{
struct ioctl_gntdev_get_offset_for_vaddr op;
struct vm_area_struct *vma;
struct grant_map *map;
struct gntdev_grant_map *map;
int rv = -EINVAL;
if (copy_from_user(&op, u, sizeof(op)) != 0)
@ -677,7 +741,7 @@ static long gntdev_ioctl_get_offset_for_vaddr(struct gntdev_priv *priv,
static long gntdev_ioctl_notify(struct gntdev_priv *priv, void __user *u)
{
struct ioctl_gntdev_unmap_notify op;
struct grant_map *map;
struct gntdev_grant_map *map;
int rc;
int out_flags;
unsigned int out_event;
@ -962,6 +1026,20 @@ static long gntdev_ioctl(struct file *flip,
case IOCTL_GNTDEV_GRANT_COPY:
return gntdev_ioctl_grant_copy(priv, ptr);
#ifdef CONFIG_XEN_GNTDEV_DMABUF
case IOCTL_GNTDEV_DMABUF_EXP_FROM_REFS:
return gntdev_ioctl_dmabuf_exp_from_refs(priv, use_ptemod, ptr);
case IOCTL_GNTDEV_DMABUF_EXP_WAIT_RELEASED:
return gntdev_ioctl_dmabuf_exp_wait_released(priv, ptr);
case IOCTL_GNTDEV_DMABUF_IMP_TO_REFS:
return gntdev_ioctl_dmabuf_imp_to_refs(priv, ptr);
case IOCTL_GNTDEV_DMABUF_IMP_RELEASE:
return gntdev_ioctl_dmabuf_imp_release(priv, ptr);
#endif
default:
pr_debug("priv %p, unknown cmd %x\n", priv, cmd);
return -ENOIOCTLCMD;
@ -975,7 +1053,7 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
struct gntdev_priv *priv = flip->private_data;
int index = vma->vm_pgoff;
int count = vma_pages(vma);
struct grant_map *map;
struct gntdev_grant_map *map;
int i, err = -EINVAL;
if ((vma->vm_flags & VM_WRITE) && !(vma->vm_flags & VM_SHARED))
@ -1032,7 +1110,7 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma)
}
}
err = map_grant_pages(map);
err = gntdev_map_grant_pages(map);
if (err)
goto out_put_map;

151
drivers/xen/grant-table.c
View File

@ -45,6 +45,9 @@
#include <linux/workqueue.h>
#include <linux/ratelimit.h>
#include <linux/moduleparam.h>
#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
#include <linux/dma-mapping.h>
#endif
#include <xen/xen.h>
#include <xen/interface/xen.h>
@ -57,6 +60,7 @@
#ifdef CONFIG_X86
#include <asm/xen/cpuid.h>
#endif
#include <xen/mem-reservation.h>
#include <asm/xen/hypercall.h>
#include <asm/xen/interface.h>
@ -769,29 +773,18 @@ void gnttab_free_auto_xlat_frames(void)
}
EXPORT_SYMBOL_GPL(gnttab_free_auto_xlat_frames);
/**
* gnttab_alloc_pages - alloc pages suitable for grant mapping into
* @nr_pages: number of pages to alloc
* @pages: returns the pages
*/
int gnttab_alloc_pages(int nr_pages, struct page **pages)
int gnttab_pages_set_private(int nr_pages, struct page **pages)
{
int i;
int ret;
ret = alloc_xenballooned_pages(nr_pages, pages);
if (ret < 0)
return ret;
for (i = 0; i < nr_pages; i++) {
#if BITS_PER_LONG < 64
struct xen_page_foreign *foreign;
foreign = kzalloc(sizeof(*foreign), GFP_KERNEL);
if (!foreign) {
gnttab_free_pages(nr_pages, pages);
if (!foreign)
return -ENOMEM;
}
set_page_private(pages[i], (unsigned long)foreign);
#endif
SetPagePrivate(pages[i]);
@ -799,14 +792,30 @@ int gnttab_alloc_pages(int nr_pages, struct page **pages)
return 0;
}
EXPORT_SYMBOL_GPL(gnttab_alloc_pages);
EXPORT_SYMBOL_GPL(gnttab_pages_set_private);
/**
* gnttab_free_pages - free pages allocated by gnttab_alloc_pages()
* @nr_pages; number of pages to free
* @pages: the pages
* gnttab_alloc_pages - alloc pages suitable for grant mapping into
* @nr_pages: number of pages to alloc
* @pages: returns the pages
*/
void gnttab_free_pages(int nr_pages, struct page **pages)
int gnttab_alloc_pages(int nr_pages, struct page **pages)
{
int ret;
ret = alloc_xenballooned_pages(nr_pages, pages);
if (ret < 0)
return ret;
ret = gnttab_pages_set_private(nr_pages, pages);
if (ret < 0)
gnttab_free_pages(nr_pages, pages);
return ret;
}
EXPORT_SYMBOL_GPL(gnttab_alloc_pages);
void gnttab_pages_clear_private(int nr_pages, struct page **pages)
{
int i;
@ -818,10 +827,114 @@ void gnttab_free_pages(int nr_pages, struct page **pages)
ClearPagePrivate(pages[i]);
}
}
}
EXPORT_SYMBOL_GPL(gnttab_pages_clear_private);
/**
* gnttab_free_pages - free pages allocated by gnttab_alloc_pages()
* @nr_pages; number of pages to free
* @pages: the pages
*/
void gnttab_free_pages(int nr_pages, struct page **pages)
{
gnttab_pages_clear_private(nr_pages, pages);
free_xenballooned_pages(nr_pages, pages);
}
EXPORT_SYMBOL_GPL(gnttab_free_pages);
#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
/**
* gnttab_dma_alloc_pages - alloc DMAable pages suitable for grant mapping into
* @args: arguments to the function
*/
int gnttab_dma_alloc_pages(struct gnttab_dma_alloc_args *args)
{
unsigned long pfn, start_pfn;
size_t size;
int i, ret;
size = args->nr_pages << PAGE_SHIFT;
if (args->coherent)
args->vaddr = dma_alloc_coherent(args->dev, size,
&args->dev_bus_addr,
GFP_KERNEL | __GFP_NOWARN);
else
args->vaddr = dma_alloc_wc(args->dev, size,
&args->dev_bus_addr,
GFP_KERNEL | __GFP_NOWARN);
if (!args->vaddr) {
pr_debug("Failed to allocate DMA buffer of size %zu\n", size);
return -ENOMEM;
}
start_pfn = __phys_to_pfn(args->dev_bus_addr);
for (pfn = start_pfn, i = 0; pfn < start_pfn + args->nr_pages;
pfn++, i++) {
struct page *page = pfn_to_page(pfn);
args->pages[i] = page;
args->frames[i] = xen_page_to_gfn(page);
xenmem_reservation_scrub_page(page);
}
xenmem_reservation_va_mapping_reset(args->nr_pages, args->pages);
ret = xenmem_reservation_decrease(args->nr_pages, args->frames);
if (ret != args->nr_pages) {
pr_debug("Failed to decrease reservation for DMA buffer\n");
ret = -EFAULT;
goto fail;
}
ret = gnttab_pages_set_private(args->nr_pages, args->pages);
if (ret < 0)
goto fail;
return 0;
fail:
gnttab_dma_free_pages(args);
return ret;
}
EXPORT_SYMBOL_GPL(gnttab_dma_alloc_pages);
/**
* gnttab_dma_free_pages - free DMAable pages
* @args: arguments to the function
*/
int gnttab_dma_free_pages(struct gnttab_dma_alloc_args *args)
{
size_t size;
int i, ret;
gnttab_pages_clear_private(args->nr_pages, args->pages);
for (i = 0; i < args->nr_pages; i++)
args->frames[i] = page_to_xen_pfn(args->pages[i]);
ret = xenmem_reservation_increase(args->nr_pages, args->frames);
if (ret != args->nr_pages) {
pr_debug("Failed to decrease reservation for DMA buffer\n");
ret = -EFAULT;
} else {
ret = 0;
}
xenmem_reservation_va_mapping_update(args->nr_pages, args->pages,
args->frames);
size = args->nr_pages << PAGE_SHIFT;
if (args->coherent)
dma_free_coherent(args->dev, size,
args->vaddr, args->dev_bus_addr);
else
dma_free_wc(args->dev, size,
args->vaddr, args->dev_bus_addr);
return ret;
}
EXPORT_SYMBOL_GPL(gnttab_dma_free_pages);
#endif
/* Handling of paged out grant targets (GNTST_eagain) */
#define MAX_DELAY 256
static inline void

118
drivers/xen/mem-reservation.c Normal file
View File

@ -0,0 +1,118 @@
// SPDX-License-Identifier: GPL-2.0
/******************************************************************************
* Xen memory reservation utilities.
*
* Copyright (c) 2003, B Dragovic
* Copyright (c) 2003-2004, M Williamson, K Fraser
* Copyright (c) 2005 Dan M. Smith, IBM Corporation
* Copyright (c) 2010 Daniel Kiper
* Copyright (c) 2018 Oleksandr Andrushchenko, EPAM Systems Inc.
*/
#include <asm/xen/hypercall.h>
#include <xen/interface/memory.h>
#include <xen/mem-reservation.h>
/*
* Use one extent per PAGE_SIZE to avoid to break down the page into
* multiple frame.
*/
#define EXTENT_ORDER (fls(XEN_PFN_PER_PAGE) - 1)
#ifdef CONFIG_XEN_HAVE_PVMMU
void __xenmem_reservation_va_mapping_update(unsigned long count,
struct page **pages,
xen_pfn_t *frames)
{
int i;
for (i = 0; i < count; i++) {
struct page *page = pages[i];
unsigned long pfn = page_to_pfn(page);
BUG_ON(!page);
/*
* We don't support PV MMU when Linux and Xen is using
* different page granularity.
*/
BUILD_BUG_ON(XEN_PAGE_SIZE != PAGE_SIZE);
set_phys_to_machine(pfn, frames[i]);
/* Link back into the page tables if not highmem. */
if (!PageHighMem(page)) {
int ret;
ret = HYPERVISOR_update_va_mapping(
(unsigned long)__va(pfn << PAGE_SHIFT),
mfn_pte(frames[i], PAGE_KERNEL),
0);
BUG_ON(ret);
}
}
}
EXPORT_SYMBOL_GPL(__xenmem_reservation_va_mapping_update);
void __xenmem_reservation_va_mapping_reset(unsigned long count,
struct page **pages)
{
int i;
for (i = 0; i < count; i++) {
struct page *page = pages[i];
unsigned long pfn = page_to_pfn(page);
/*
* We don't support PV MMU when Linux and Xen are using
* different page granularity.
*/
BUILD_BUG_ON(XEN_PAGE_SIZE != PAGE_SIZE);
if (!PageHighMem(page)) {
int ret;
ret = HYPERVISOR_update_va_mapping(
(unsigned long)__va(pfn << PAGE_SHIFT),
__pte_ma(0), 0);
BUG_ON(ret);
}
__set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
}
}
EXPORT_SYMBOL_GPL(__xenmem_reservation_va_mapping_reset);
#endif /* CONFIG_XEN_HAVE_PVMMU */
/* @frames is an array of PFNs */
int xenmem_reservation_increase(int count, xen_pfn_t *frames)
{
struct xen_memory_reservation reservation = {
.address_bits = 0,
.extent_order = EXTENT_ORDER,
.domid = DOMID_SELF
};
/* XENMEM_populate_physmap requires a PFN based on Xen granularity. */
set_xen_guest_handle(reservation.extent_start, frames);
reservation.nr_extents = count;
return HYPERVISOR_memory_op(XENMEM_populate_physmap, &reservation);
}
EXPORT_SYMBOL_GPL(xenmem_reservation_increase);
/* @frames is an array of GFNs */
int xenmem_reservation_decrease(int count, xen_pfn_t *frames)
{
struct xen_memory_reservation reservation = {
.address_bits = 0,
.extent_order = EXTENT_ORDER,
.domid = DOMID_SELF
};
/* XENMEM_decrease_reservation requires a GFN */
set_xen_guest_handle(reservation.extent_start, frames);
reservation.nr_extents = count;
return HYPERVISOR_memory_op(XENMEM_decrease_reservation, &reservation);
}
EXPORT_SYMBOL_GPL(xenmem_reservation_decrease);

2
drivers/xen/xen-balloon.c
View File

@ -81,7 +81,7 @@ static void watch_target(struct xenbus_watch *watch,
static_max = new_target;
else
static_max >>= PAGE_SHIFT - 10;
target_diff = xen_pv_domain() ? 0
target_diff = (xen_pv_domain() || xen_initial_domain()) ? 0
: static_max - balloon_stats.target_pages;
}

106
include/uapi/xen/gntdev.h
View File

@ -5,6 +5,7 @@
* Interface to /dev/xen/gntdev.
*
* Copyright (c) 2007, D G Murray
* Copyright (c) 2018, Oleksandr Andrushchenko, EPAM Systems Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version 2
@ -200,4 +201,109 @@ struct ioctl_gntdev_grant_copy {
/* Send an interrupt on the indicated event channel */
#define UNMAP_NOTIFY_SEND_EVENT 0x2
/*
* Flags to be used while requesting memory mapping's backing storage
* to be allocated with DMA API.
*/
/*
* The buffer is backed with memory allocated with dma_alloc_wc.
*/
#define GNTDEV_DMA_FLAG_WC (1 << 0)
/*
* The buffer is backed with memory allocated with dma_alloc_coherent.
*/
#define GNTDEV_DMA_FLAG_COHERENT (1 << 1)
/*
* Create a dma-buf [1] from grant references @refs of count @count provided
* by the foreign domain @domid with flags @flags.
*
* By default dma-buf is backed by system memory pages, but by providing
* one of the GNTDEV_DMA_FLAG_XXX flags it can also be created as
* a DMA write-combine or coherent buffer, e.g. allocated with dma_alloc_wc/
* dma_alloc_coherent.
*
* Returns 0 if dma-buf was successfully created and the corresponding
* dma-buf's file descriptor is returned in @fd.
*
* [1] Documentation/driver-api/dma-buf.rst
*/
#define IOCTL_GNTDEV_DMABUF_EXP_FROM_REFS \
_IOC(_IOC_NONE, 'G', 9, \
sizeof(struct ioctl_gntdev_dmabuf_exp_from_refs))
struct ioctl_gntdev_dmabuf_exp_from_refs {
/* IN parameters. */
/* Specific options for this dma-buf: see GNTDEV_DMA_FLAG_XXX. */
__u32 flags;
/* Number of grant references in @refs array. */
__u32 count;
/* OUT parameters. */
/* File descriptor of the dma-buf. */
__u32 fd;
/* The domain ID of the grant references to be mapped. */
__u32 domid;
/* Variable IN parameter. */
/* Array of grant references of size @count. */
__u32 refs[1];
};
/*
* This will block until the dma-buf with the file descriptor @fd is
* released. This is only valid for buffers created with
* IOCTL_GNTDEV_DMABUF_EXP_FROM_REFS.
*
* If within @wait_to_ms milliseconds the buffer is not released
* then -ETIMEDOUT error is returned.
* If the buffer with the file descriptor @fd does not exist or has already
* been released, then -ENOENT is returned. For valid file descriptors
* this must not be treated as error.
*/
#define IOCTL_GNTDEV_DMABUF_EXP_WAIT_RELEASED \
_IOC(_IOC_NONE, 'G', 10, \
sizeof(struct ioctl_gntdev_dmabuf_exp_wait_released))
struct ioctl_gntdev_dmabuf_exp_wait_released {
/* IN parameters */
__u32 fd;
__u32 wait_to_ms;
};
/*
* Import a dma-buf with file descriptor @fd and export granted references
* to the pages of that dma-buf into array @refs of size @count.
*/
#define IOCTL_GNTDEV_DMABUF_IMP_TO_REFS \
_IOC(_IOC_NONE, 'G', 11, \
sizeof(struct ioctl_gntdev_dmabuf_imp_to_refs))
struct ioctl_gntdev_dmabuf_imp_to_refs {
/* IN parameters. */
/* File descriptor of the dma-buf. */
__u32 fd;
/* Number of grant references in @refs array. */
__u32 count;
/* The domain ID for which references to be granted. */
__u32 domid;
/* Reserved - must be zero. */
__u32 reserved;
/* OUT parameters. */
/* Array of grant references of size @count. */
__u32 refs[1];
};
/*
* This will close all references to the imported buffer with file descriptor
* @fd, so it can be released by the owner. This is only valid for buffers
* created with IOCTL_GNTDEV_DMABUF_IMP_TO_REFS.
*/
#define IOCTL_GNTDEV_DMABUF_IMP_RELEASE \
_IOC(_IOC_NONE, 'G', 12, \
sizeof(struct ioctl_gntdev_dmabuf_imp_release))
struct ioctl_gntdev_dmabuf_imp_release {
/* IN parameters */
__u32 fd;
__u32 reserved;
};
#endif /* __LINUX_PUBLIC_GNTDEV_H__ */

21
include/xen/grant_table.h
View File

@ -198,6 +198,27 @@ void gnttab_free_auto_xlat_frames(void);
int gnttab_alloc_pages(int nr_pages, struct page **pages);
void gnttab_free_pages(int nr_pages, struct page **pages);
#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
struct gnttab_dma_alloc_args {
/* Device for which DMA memory will be/was allocated. */
struct device *dev;
/* If set then DMA buffer is coherent and write-combine otherwise. */
bool coherent;
int nr_pages;
struct page **pages;
xen_pfn_t *frames;
void *vaddr;
dma_addr_t dev_bus_addr;
};
int gnttab_dma_alloc_pages(struct gnttab_dma_alloc_args *args);
int gnttab_dma_free_pages(struct gnttab_dma_alloc_args *args);
#endif
int gnttab_pages_set_private(int nr_pages, struct page **pages);
void gnttab_pages_clear_private(int nr_pages, struct page **pages);
int gnttab_map_refs(struct gnttab_map_grant_ref *map_ops,
struct gnttab_map_grant_ref *kmap_ops,
struct page **pages, unsigned int count);

59
include/xen/mem-reservation.h Normal file
View File

@ -0,0 +1,59 @@
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Xen memory reservation utilities.
*
* Copyright (c) 2003, B Dragovic
* Copyright (c) 2003-2004, M Williamson, K Fraser
* Copyright (c) 2005 Dan M. Smith, IBM Corporation
* Copyright (c) 2010 Daniel Kiper
* Copyright (c) 2018 Oleksandr Andrushchenko, EPAM Systems Inc.
*/
#ifndef _XENMEM_RESERVATION_H
#define _XENMEM_RESERVATION_H
#include <linux/highmem.h>
#include <xen/page.h>
static inline void xenmem_reservation_scrub_page(struct page *page)
{
#ifdef CONFIG_XEN_SCRUB_PAGES
clear_highpage(page);
#endif
}
#ifdef CONFIG_XEN_HAVE_PVMMU
void __xenmem_reservation_va_mapping_update(unsigned long count,
struct page **pages,
xen_pfn_t *frames);
void __xenmem_reservation_va_mapping_reset(unsigned long count,
struct page **pages);
#endif
static inline void xenmem_reservation_va_mapping_update(unsigned long count,
struct page **pages,
xen_pfn_t *frames)
{
#ifdef CONFIG_XEN_HAVE_PVMMU
if (!xen_feature(XENFEAT_auto_translated_physmap))
__xenmem_reservation_va_mapping_update(count, pages, frames);
#endif
}
static inline void xenmem_reservation_va_mapping_reset(unsigned long count,
struct page **pages)
{
#ifdef CONFIG_XEN_HAVE_PVMMU
if (!xen_feature(XENFEAT_auto_translated_physmap))
__xenmem_reservation_va_mapping_reset(count, pages);
#endif
}
int xenmem_reservation_increase(int count, xen_pfn_t *frames);
int xenmem_reservation_decrease(int count, xen_pfn_t *frames);
#endif