// 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/dma-direct.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/uaccess.h>
#include <linux/module.h>
#include <xen/xen.h>
#include <xen/grant_table.h>
#include "gntdev-common.h"
#include "gntdev-dmabuf.h"
MODULE_IMPORT_NS(DMA_BUF);
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 (only for dma-buf export). */
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;
/*
* We reference this file while exporting dma-bufs, so
* the grant device context is not destroyed while there are
* external users alive.
*/
struct file *filp;
};
/* 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 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_sgtable(attach->dev, sgt,
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_sgtable(attach->dev, sgt, 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);
fput(gntdev_dmabuf->priv->filp);
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 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,
};
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);
get_file(gntdev_dmabuf->priv->filp);
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(gntdev_test_page_count(count)))
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);
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(unsigned long *gfns, 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,
gfns[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] != INVALID_GRANT_REF)
gnttab_end_foreign_access(refs[i], NULL);
}
static void dmabuf_imp_free_storage(struct gntdev_dmabuf *gntdev_dmabuf)
{
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->nr_pages = count;
for (i = 0; i < count; i++)
gntdev_dmabuf->u.imp.refs[i] = INVALID_GRANT_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_dma_page_iter sg_iter;
unsigned long *gfns;
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_unlocked(attach, DMA_BIDIRECTIONAL);
if (IS_ERR(sgt)) {
ret = ERR_CAST(sgt);
goto fail_detach;
}
/* Check that we have zero offset. */
if (sgt->sgl->offset) {
ret = ERR_PTR(-EINVAL);
pr_debug("DMA buffer has %d bytes offset, user-space expects 0\n",
sgt->sgl->offset);
goto fail_unmap;
}
/* 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;
gfns = kcalloc(count, sizeof(*gfns), GFP_KERNEL);
if (!gfns) {
ret = ERR_PTR(-ENOMEM);
goto fail_unmap;
}
/*
* Now convert sgt to array of gfns without accessing underlying pages.
* It is not allowed to access the underlying struct page of an sg table
* exported by DMA-buf, but since we deal with special Xen dma device here
* (not a normal physical one) look at the dma addresses in the sg table
* and then calculate gfns directly from them.
*/
i = 0;
for_each_sgtable_dma_page(sgt, &sg_iter, 0) {
dma_addr_t addr = sg_page_iter_dma_address(&sg_iter);
unsigned long pfn = bfn_to_pfn(XEN_PFN_DOWN(dma_to_phys(dev, addr)));
gfns[i++] = pfn_to_gfn(pfn);
}
ret = ERR_PTR(dmabuf_imp_grant_foreign_access(gfns,
gntdev_dmabuf->u.imp.refs,
count, domid));
kfree(gfns);
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_unlocked(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_unlocked(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;
}
static void dmabuf_imp_release_all(struct gntdev_dmabuf_priv *priv)
{
struct gntdev_dmabuf *q, *gntdev_dmabuf;
list_for_each_entry_safe(gntdev_dmabuf, q, &priv->imp_list, next)
dmabuf_imp_release(priv, gntdev_dmabuf->fd);
}
/* 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(gntdev_test_page_count(op.count)))
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(gntdev_test_page_count(op.count)))
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(struct file *filp)
{
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);
priv->filp = filp;
return priv;
}
void gntdev_dmabuf_fini(struct gntdev_dmabuf_priv *priv)
{
dmabuf_imp_release_all(priv);
kfree(priv);
}
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