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path: root/drivers/usb/gadget/inode.c
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Diffstat (limited to 'drivers/usb/gadget/inode.c')
-rw-r--r--drivers/usb/gadget/inode.c44
1 files changed, 31 insertions, 13 deletions
diff --git a/drivers/usb/gadget/inode.c b/drivers/usb/gadget/inode.c
index e2b2e9cf254..570c005062a 100644
--- a/drivers/usb/gadget/inode.c
+++ b/drivers/usb/gadget/inode.c
@@ -24,6 +24,8 @@
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/poll.h>
+#include <linux/mmu_context.h>
+#include <linux/aio.h>
#include <linux/device.h>
#include <linux/moduleparam.h>
@@ -513,6 +515,9 @@ static long ep_ioctl(struct file *fd, unsigned code, unsigned long value)
struct kiocb_priv {
struct usb_request *req;
struct ep_data *epdata;
+ struct kiocb *iocb;
+ struct mm_struct *mm;
+ struct work_struct work;
void *buf;
const struct iovec *iv;
unsigned long nr_segs;
@@ -528,7 +533,6 @@ static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
local_irq_disable();
epdata = priv->epdata;
// spin_lock(&epdata->dev->lock);
- kiocbSetCancelled(iocb);
if (likely(epdata && epdata->ep && priv->req))
value = usb_ep_dequeue (epdata->ep, priv->req);
else
@@ -540,15 +544,12 @@ static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
return value;
}
-static ssize_t ep_aio_read_retry(struct kiocb *iocb)
+static ssize_t ep_copy_to_user(struct kiocb_priv *priv)
{
- struct kiocb_priv *priv = iocb->private;
ssize_t len, total;
void *to_copy;
int i;
- /* we "retry" to get the right mm context for this: */
-
/* copy stuff into user buffers */
total = priv->actual;
len = 0;
@@ -568,9 +569,26 @@ static ssize_t ep_aio_read_retry(struct kiocb *iocb)
if (total == 0)
break;
}
+
+ return len;
+}
+
+static void ep_user_copy_worker(struct work_struct *work)
+{
+ struct kiocb_priv *priv = container_of(work, struct kiocb_priv, work);
+ struct mm_struct *mm = priv->mm;
+ struct kiocb *iocb = priv->iocb;
+ size_t ret;
+
+ use_mm(mm);
+ ret = ep_copy_to_user(priv);
+ unuse_mm(mm);
+
+ /* completing the iocb can drop the ctx and mm, don't touch mm after */
+ aio_complete(iocb, ret, ret);
+
kfree(priv->buf);
kfree(priv);
- return len;
}
static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
@@ -596,14 +614,14 @@ static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
aio_complete(iocb, req->actual ? req->actual : req->status,
req->status);
} else {
- /* retry() won't report both; so we hide some faults */
+ /* ep_copy_to_user() won't report both; we hide some faults */
if (unlikely(0 != req->status))
DBG(epdata->dev, "%s fault %d len %d\n",
ep->name, req->status, req->actual);
priv->buf = req->buf;
priv->actual = req->actual;
- kick_iocb(iocb);
+ schedule_work(&priv->work);
}
spin_unlock(&epdata->dev->lock);
@@ -633,8 +651,10 @@ fail:
return value;
}
iocb->private = priv;
+ priv->iocb = iocb;
priv->iv = iv;
priv->nr_segs = nr_segs;
+ INIT_WORK(&priv->work, ep_user_copy_worker);
value = get_ready_ep(iocb->ki_filp->f_flags, epdata);
if (unlikely(value < 0)) {
@@ -642,10 +662,11 @@ fail:
goto fail;
}
- iocb->ki_cancel = ep_aio_cancel;
+ kiocb_set_cancel_fn(iocb, ep_aio_cancel);
get_ep(epdata);
priv->epdata = epdata;
priv->actual = 0;
+ priv->mm = current->mm; /* mm teardown waits for iocbs in exit_aio() */
/* each kiocb is coupled to one usb_request, but we can't
* allocate or submit those if the host disconnected.
@@ -674,7 +695,7 @@ fail:
kfree(priv);
put_ep(epdata);
} else
- value = (iv ? -EIOCBRETRY : -EIOCBQUEUED);
+ value = -EIOCBQUEUED;
return value;
}
@@ -692,7 +713,6 @@ ep_aio_read(struct kiocb *iocb, const struct iovec *iov,
if (unlikely(!buf))
return -ENOMEM;
- iocb->ki_retry = ep_aio_read_retry;
return ep_aio_rwtail(iocb, buf, iocb->ki_left, epdata, iov, nr_segs);
}
@@ -887,7 +907,6 @@ ep_open (struct inode *inode, struct file *fd)
/* used before endpoint configuration */
static const struct file_operations ep_config_operations = {
- .owner = THIS_MODULE,
.llseek = no_llseek,
.open = ep_open,
@@ -1940,7 +1959,6 @@ dev_open (struct inode *inode, struct file *fd)
}
static const struct file_operations dev_init_operations = {
- .owner = THIS_MODULE,
.llseek = no_llseek,
.open = dev_open,