[PATCH] Vectorize aio_read/aio_write fileop methods

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / usb / gadget / inode.c

diff --git a/drivers/usb/gadget/inode.c b/drivers/usb/gadget/inode.c
index 4a000d846a936cc56ec8201d654c2135978aede1..86924f9cdd7e0c5e57845e4f4a41d63a188414b2 100644 (file)
--- a/drivers/usb/gadget/inode.c
+++ b/drivers/usb/gadget/inode.c
@@ -533,7 +533,8 @@ struct kiocb_priv {
        struct usb_request      *req;
        struct ep_data          *epdata;
        void                    *buf;
-       char __user             *ubuf;          /* NULL for writes */
+       const struct iovec      *iv;
+       unsigned long           nr_segs;
        unsigned                actual;
 };
 
@@ -561,17 +562,32 @@ static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
 static ssize_t ep_aio_read_retry(struct kiocb *iocb)
 {
        struct kiocb_priv       *priv = iocb->private;
-       ssize_t                 status = priv->actual;
-
-       /* we "retry" to get the right mm context for this: */
-       status = copy_to_user(priv->ubuf, priv->buf, priv->actual);
-       if (unlikely(0 != status))
-               status = -EFAULT;
-       else
-               status = priv->actual;
-       kfree(priv->buf);
-       kfree(priv);
-       return status;
+       ssize_t                 len, total;
+       int                     i;
+
+       /* we "retry" to get the right mm context for this: */
+
+       /* copy stuff into user buffers */
+       total = priv->actual;
+       len = 0;
+       for (i=0; i < priv->nr_segs; i++) {
+               ssize_t this = min((ssize_t)(priv->iv[i].iov_len), total);
+
+               if (copy_to_user(priv->iv[i].iov_base, priv->buf, this)) {
+                       if (len == 0)
+                               len = -EFAULT;
+                       break;
+               }
+
+               total -= this;
+               len += this;
+               if (total == 0)
+                       break;
+       }
+       kfree(priv->buf);
+       kfree(priv);
+       aio_put_req(iocb);
+       return len;
 }
 
 static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
@@ -584,7 +600,7 @@ static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
        spin_lock(&epdata->dev->lock);
        priv->req = NULL;
        priv->epdata = NULL;
-       if (priv->ubuf == NULL
+       if (priv->iv == NULL
                        || unlikely(req->actual == 0)
                        || unlikely(kiocbIsCancelled(iocb))) {
                kfree(req->buf);
@@ -619,7 +635,8 @@ ep_aio_rwtail(
        char            *buf,
        size_t          len,
        struct ep_data  *epdata,
-       char __user     *ubuf
+       const struct iovec *iv,
+       unsigned long   nr_segs
 )
 {
        struct kiocb_priv       *priv;
@@ -634,7 +651,8 @@ fail:
                return value;
        }
        iocb->private = priv;
-       priv->ubuf = ubuf;
+       priv->iv = iv;
+       priv->nr_segs = nr_segs;
 
        value = get_ready_ep(iocb->ki_filp->f_flags, epdata);
        if (unlikely(value < 0)) {
@@ -674,41 +692,53 @@ fail:
                kfree(priv);
                put_ep(epdata);
        } else
-               value = (ubuf ? -EIOCBRETRY : -EIOCBQUEUED);
+               value = (iv ? -EIOCBRETRY : -EIOCBQUEUED);
        return value;
 }
 
 static ssize_t
-ep_aio_read(struct kiocb *iocb, char __user *ubuf, size_t len, loff_t o)
+ep_aio_read(struct kiocb *iocb, const struct iovec *iov,
+               unsigned long nr_segs, loff_t o)
 {
        struct ep_data          *epdata = iocb->ki_filp->private_data;
        char                    *buf;
 
        if (unlikely(epdata->desc.bEndpointAddress & USB_DIR_IN))
                return -EINVAL;
-       buf = kmalloc(len, GFP_KERNEL);
+
+       buf = kmalloc(iocb->ki_left, GFP_KERNEL);
        if (unlikely(!buf))
                return -ENOMEM;
+
        iocb->ki_retry = ep_aio_read_retry;
-       return ep_aio_rwtail(iocb, buf, len, epdata, ubuf);
+       return ep_aio_rwtail(iocb, buf, iocb->ki_left, epdata, iov, nr_segs);
 }
 
 static ssize_t
-ep_aio_write(struct kiocb *iocb, const char __user *ubuf, size_t len, loff_t o)
+ep_aio_write(struct kiocb *iocb, const struct iovec *iov,
+               unsigned long nr_segs, loff_t o)
 {
        struct ep_data          *epdata = iocb->ki_filp->private_data;
        char                    *buf;
+       size_t                  len = 0;
+       int                     i = 0;
 
        if (unlikely(!(epdata->desc.bEndpointAddress & USB_DIR_IN)))
                return -EINVAL;
-       buf = kmalloc(len, GFP_KERNEL);
+
+       buf = kmalloc(iocb->ki_left, GFP_KERNEL);
        if (unlikely(!buf))
                return -ENOMEM;
-       if (unlikely(copy_from_user(buf, ubuf, len) != 0)) {
-               kfree(buf);
-               return -EFAULT;
+
+       for (i=0; i < nr_segs; i++) {
+               if (unlikely(copy_from_user(&buf[len], iov[i].iov_base,
+                               iov[i].iov_len) != 0)) {
+                       kfree(buf);
+                       return -EFAULT;
+               }
+               len += iov[i].iov_len;
        }
-       return ep_aio_rwtail(iocb, buf, len, epdata, NULL);
+       return ep_aio_rwtail(iocb, buf, len, epdata, NULL, 0);
 }
 
 /*----------------------------------------------------------------------*/