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authorLinus Torvalds <torvalds@linux-foundation.org>2014-04-01 16:13:21 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-04-01 16:13:21 -0700
commit675c354a95d5375153b8bb80a0448cab916c7991 (patch)
tree88cbc5a5a31dd1c1016271006a8d56cfe0abf7bd /drivers/hv
parentc70929147a10fa4538886cb23b934b509c4c0e49 (diff)
parent1b3fa22e0234d613df967445cd34807e10fa54fa (diff)
downloadlinux-675c354a95d5375153b8bb80a0448cab916c7991.tar.gz
Merge tag 'char-misc-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver patches from Greg KH:
 "Here's the big char/misc driver updates for 3.15-rc1.

  Lots of various things here, including the new mcb driver subsystem.

  All of these have been in linux-next for a while"

* tag 'char-misc-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (118 commits)
  extcon: Move OF helper function to extcon core and change function name
  extcon: of: Remove unnecessary function call by using the name of device_node
  extcon: gpio: Use SIMPLE_DEV_PM_OPS macro
  extcon: palmas: Use SIMPLE_DEV_PM_OPS macro
  mei: don't use deprecated DEFINE_PCI_DEVICE_TABLE macro
  mei: amthif: fix checkpatch error
  mei: client.h fix checkpatch errors
  mei: use cl_dbg where appropriate
  mei: fix Unnecessary space after function pointer name
  mei: report consistently copy_from/to_user failures
  mei: drop pr_fmt macros
  mei: make me hw headers private to me hw.
  mei: fix memory leak of pending write cb objects
  mei: me: do not reset when less than expected data is received
  drivers: mcb: Fix build error discovered by 0-day bot
  cs5535-mfgpt: Simplify dependencies
  spmi: pm: drop bus-level PM suspend/resume routines
  spmi: pmic_arb: make selectable on ARCH_QCOM
  Drivers: hv: vmbus: Increase the limit on the number of pfns we can handle
  pch_phub: Report error writing MAC back to user
  ...
Diffstat (limited to 'drivers/hv')
-rw-r--r--drivers/hv/Makefile2
-rw-r--r--drivers/hv/channel.c42
-rw-r--r--drivers/hv/hv_balloon.c3
-rw-r--r--drivers/hv/hv_fcopy.c414
-rw-r--r--drivers/hv/hv_kvp.c4
-rw-r--r--drivers/hv/hv_snapshot.c2
-rw-r--r--drivers/hv/hv_util.c11
-rw-r--r--drivers/hv/hyperv_vmbus.h8
-rw-r--r--drivers/hv/ring_buffer.c17
-rw-r--r--drivers/hv/vmbus_drv.c51
10 files changed, 505 insertions, 49 deletions
diff --git a/drivers/hv/Makefile b/drivers/hv/Makefile
index 0a74b5661186..5e4dfa4cfe22 100644
--- a/drivers/hv/Makefile
+++ b/drivers/hv/Makefile
@@ -5,4 +5,4 @@ obj-$(CONFIG_HYPERV_BALLOON)	+= hv_balloon.o
 hv_vmbus-y := vmbus_drv.o \
 		 hv.o connection.o channel.o \
 		 channel_mgmt.o ring_buffer.o
-hv_utils-y := hv_util.o hv_kvp.o hv_snapshot.o
+hv_utils-y := hv_util.o hv_kvp.o hv_snapshot.o hv_fcopy.o
diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
index 69ea36f07b4d..602ca86a6488 100644
--- a/drivers/hv/channel.c
+++ b/drivers/hv/channel.c
@@ -27,6 +27,7 @@
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/hyperv.h>
+#include <linux/uio.h>
 
 #include "hyperv_vmbus.h"
 
@@ -554,14 +555,14 @@ EXPORT_SYMBOL_GPL(vmbus_close);
  *
  * Mainly used by Hyper-V drivers.
  */
-int vmbus_sendpacket(struct vmbus_channel *channel, const void *buffer,
+int vmbus_sendpacket(struct vmbus_channel *channel, void *buffer,
 			   u32 bufferlen, u64 requestid,
 			   enum vmbus_packet_type type, u32 flags)
 {
 	struct vmpacket_descriptor desc;
 	u32 packetlen = sizeof(struct vmpacket_descriptor) + bufferlen;
 	u32 packetlen_aligned = ALIGN(packetlen, sizeof(u64));
-	struct scatterlist bufferlist[3];
+	struct kvec bufferlist[3];
 	u64 aligned_data = 0;
 	int ret;
 	bool signal = false;
@@ -575,11 +576,12 @@ int vmbus_sendpacket(struct vmbus_channel *channel, const void *buffer,
 	desc.len8 = (u16)(packetlen_aligned >> 3);
 	desc.trans_id = requestid;
 
-	sg_init_table(bufferlist, 3);
-	sg_set_buf(&bufferlist[0], &desc, sizeof(struct vmpacket_descriptor));
-	sg_set_buf(&bufferlist[1], buffer, bufferlen);
-	sg_set_buf(&bufferlist[2], &aligned_data,
-		   packetlen_aligned - packetlen);
+	bufferlist[0].iov_base = &desc;
+	bufferlist[0].iov_len = sizeof(struct vmpacket_descriptor);
+	bufferlist[1].iov_base = buffer;
+	bufferlist[1].iov_len = bufferlen;
+	bufferlist[2].iov_base = &aligned_data;
+	bufferlist[2].iov_len = (packetlen_aligned - packetlen);
 
 	ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal);
 
@@ -605,7 +607,7 @@ int vmbus_sendpacket_pagebuffer(struct vmbus_channel *channel,
 	u32 descsize;
 	u32 packetlen;
 	u32 packetlen_aligned;
-	struct scatterlist bufferlist[3];
+	struct kvec bufferlist[3];
 	u64 aligned_data = 0;
 	bool signal = false;
 
@@ -637,11 +639,12 @@ int vmbus_sendpacket_pagebuffer(struct vmbus_channel *channel,
 		desc.range[i].pfn	 = pagebuffers[i].pfn;
 	}
 
-	sg_init_table(bufferlist, 3);
-	sg_set_buf(&bufferlist[0], &desc, descsize);
-	sg_set_buf(&bufferlist[1], buffer, bufferlen);
-	sg_set_buf(&bufferlist[2], &aligned_data,
-		packetlen_aligned - packetlen);
+	bufferlist[0].iov_base = &desc;
+	bufferlist[0].iov_len = descsize;
+	bufferlist[1].iov_base = buffer;
+	bufferlist[1].iov_len = bufferlen;
+	bufferlist[2].iov_base = &aligned_data;
+	bufferlist[2].iov_len = (packetlen_aligned - packetlen);
 
 	ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal);
 
@@ -665,7 +668,7 @@ int vmbus_sendpacket_multipagebuffer(struct vmbus_channel *channel,
 	u32 descsize;
 	u32 packetlen;
 	u32 packetlen_aligned;
-	struct scatterlist bufferlist[3];
+	struct kvec bufferlist[3];
 	u64 aligned_data = 0;
 	bool signal = false;
 	u32 pfncount = NUM_PAGES_SPANNED(multi_pagebuffer->offset,
@@ -700,11 +703,12 @@ int vmbus_sendpacket_multipagebuffer(struct vmbus_channel *channel,
 	memcpy(desc.range.pfn_array, multi_pagebuffer->pfn_array,
 	       pfncount * sizeof(u64));
 
-	sg_init_table(bufferlist, 3);
-	sg_set_buf(&bufferlist[0], &desc, descsize);
-	sg_set_buf(&bufferlist[1], buffer, bufferlen);
-	sg_set_buf(&bufferlist[2], &aligned_data,
-		packetlen_aligned - packetlen);
+	bufferlist[0].iov_base = &desc;
+	bufferlist[0].iov_len = descsize;
+	bufferlist[1].iov_base = buffer;
+	bufferlist[1].iov_len = bufferlen;
+	bufferlist[2].iov_base = &aligned_data;
+	bufferlist[2].iov_len = (packetlen_aligned - packetlen);
 
 	ret = hv_ringbuffer_write(&channel->outbound, bufferlist, 3, &signal);
 
diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c
index 7e17a5495e02..7e6d78dc9437 100644
--- a/drivers/hv/hv_balloon.c
+++ b/drivers/hv/hv_balloon.c
@@ -1171,7 +1171,8 @@ static int dm_thread_func(void *dm_dev)
 	int t;
 
 	while (!kthread_should_stop()) {
-		t = wait_for_completion_timeout(&dm_device.config_event, 1*HZ);
+		t = wait_for_completion_interruptible_timeout(
+						&dm_device.config_event, 1*HZ);
 		/*
 		 * The host expects us to post information on the memory
 		 * pressure every second.
diff --git a/drivers/hv/hv_fcopy.c b/drivers/hv/hv_fcopy.c
new file mode 100644
index 000000000000..eaaa3d843b80
--- /dev/null
+++ b/drivers/hv/hv_fcopy.c
@@ -0,0 +1,414 @@
+/*
+ * An implementation of file copy service.
+ *
+ * Copyright (C) 2014, Microsoft, Inc.
+ *
+ * Author : K. Y. Srinivasan <ksrinivasan@novell.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT.  See the GNU General Public License for more
+ * details.
+ *
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/semaphore.h>
+#include <linux/fs.h>
+#include <linux/nls.h>
+#include <linux/workqueue.h>
+#include <linux/cdev.h>
+#include <linux/hyperv.h>
+#include <linux/sched.h>
+#include <linux/uaccess.h>
+#include <linux/miscdevice.h>
+
+#include "hyperv_vmbus.h"
+
+#define WIN8_SRV_MAJOR		1
+#define WIN8_SRV_MINOR		1
+#define WIN8_SRV_VERSION	(WIN8_SRV_MAJOR << 16 | WIN8_SRV_MINOR)
+
+/*
+ * Global state maintained for transaction that is being processed.
+ * For a class of integration services, including the "file copy service",
+ * the specified protocol is a "request/response" protocol which means that
+ * there can only be single outstanding transaction from the host at any
+ * given point in time. We use this to simplify memory management in this
+ * driver - we cache and process only one message at a time.
+ *
+ * While the request/response protocol is guaranteed by the host, we further
+ * ensure this by serializing packet processing in this driver - we do not
+ * read additional packets from the VMBUs until the current packet is fully
+ * handled.
+ *
+ * The transaction "active" state is set when we receive a request from the
+ * host and we cleanup this state when the transaction is completed - when we
+ * respond to the host with our response. When the transaction active state is
+ * set, we defer handling incoming packets.
+ */
+
+static struct {
+	bool active; /* transaction status - active or not */
+	int recv_len; /* number of bytes received. */
+	struct hv_fcopy_hdr  *fcopy_msg; /* current message */
+	struct hv_start_fcopy  message; /*  sent to daemon */
+	struct vmbus_channel *recv_channel; /* chn we got the request */
+	u64 recv_req_id; /* request ID. */
+	void *fcopy_context; /* for the channel callback */
+	struct semaphore read_sema;
+} fcopy_transaction;
+
+static bool opened; /* currently device opened */
+
+/*
+ * Before we can accept copy messages from the host, we need
+ * to handshake with the user level daemon. This state tracks
+ * if we are in the handshake phase.
+ */
+static bool in_hand_shake = true;
+static void fcopy_send_data(void);
+static void fcopy_respond_to_host(int error);
+static void fcopy_work_func(struct work_struct *dummy);
+static DECLARE_DELAYED_WORK(fcopy_work, fcopy_work_func);
+static u8 *recv_buffer;
+
+static void fcopy_work_func(struct work_struct *dummy)
+{
+	/*
+	 * If the timer fires, the user-mode component has not responded;
+	 * process the pending transaction.
+	 */
+	fcopy_respond_to_host(HV_E_FAIL);
+}
+
+static int fcopy_handle_handshake(u32 version)
+{
+	switch (version) {
+	case FCOPY_CURRENT_VERSION:
+		break;
+	default:
+		/*
+		 * For now we will fail the registration.
+		 * If and when we have multiple versions to
+		 * deal with, we will be backward compatible.
+		 * We will add this code when needed.
+		 */
+		return -EINVAL;
+	}
+	pr_info("FCP: user-mode registering done. Daemon version: %d\n",
+		version);
+	fcopy_transaction.active = false;
+	if (fcopy_transaction.fcopy_context)
+		hv_fcopy_onchannelcallback(fcopy_transaction.fcopy_context);
+	in_hand_shake = false;
+	return 0;
+}
+
+static void fcopy_send_data(void)
+{
+	struct hv_start_fcopy *smsg_out = &fcopy_transaction.message;
+	int operation = fcopy_transaction.fcopy_msg->operation;
+	struct hv_start_fcopy *smsg_in;
+
+	/*
+	 * The  strings sent from the host are encoded in
+	 * in utf16; convert it to utf8 strings.
+	 * The host assures us that the utf16 strings will not exceed
+	 * the max lengths specified. We will however, reserve room
+	 * for the string terminating character - in the utf16s_utf8s()
+	 * function we limit the size of the buffer where the converted
+	 * string is placed to W_MAX_PATH -1 to guarantee
+	 * that the strings can be properly terminated!
+	 */
+
+	switch (operation) {
+	case START_FILE_COPY:
+		memset(smsg_out, 0, sizeof(struct hv_start_fcopy));
+		smsg_out->hdr.operation = operation;
+		smsg_in = (struct hv_start_fcopy *)fcopy_transaction.fcopy_msg;
+
+		utf16s_to_utf8s((wchar_t *)smsg_in->file_name, W_MAX_PATH,
+				UTF16_LITTLE_ENDIAN,
+				(__u8 *)smsg_out->file_name, W_MAX_PATH - 1);
+
+		utf16s_to_utf8s((wchar_t *)smsg_in->path_name, W_MAX_PATH,
+				UTF16_LITTLE_ENDIAN,
+				(__u8 *)smsg_out->path_name, W_MAX_PATH - 1);
+
+		smsg_out->copy_flags = smsg_in->copy_flags;
+		smsg_out->file_size = smsg_in->file_size;
+		break;
+
+	default:
+		break;
+	}
+	up(&fcopy_transaction.read_sema);
+	return;
+}
+
+/*
+ * Send a response back to the host.
+ */
+
+static void
+fcopy_respond_to_host(int error)
+{
+	struct icmsg_hdr *icmsghdr;
+	u32 buf_len;
+	struct vmbus_channel *channel;
+	u64 req_id;
+
+	/*
+	 * Copy the global state for completing the transaction. Note that
+	 * only one transaction can be active at a time. This is guaranteed
+	 * by the file copy protocol implemented by the host. Furthermore,
+	 * the "transaction active" state we maintain ensures that there can
+	 * only be one active transaction at a time.
+	 */
+
+	buf_len = fcopy_transaction.recv_len;
+	channel = fcopy_transaction.recv_channel;
+	req_id = fcopy_transaction.recv_req_id;
+
+	fcopy_transaction.active = false;
+
+	icmsghdr = (struct icmsg_hdr *)
+			&recv_buffer[sizeof(struct vmbuspipe_hdr)];
+
+	if (channel->onchannel_callback == NULL)
+		/*
+		 * We have raced with util driver being unloaded;
+		 * silently return.
+		 */
+		return;
+
+	icmsghdr->status = error;
+	icmsghdr->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE;
+	vmbus_sendpacket(channel, recv_buffer, buf_len, req_id,
+				VM_PKT_DATA_INBAND, 0);
+}
+
+void hv_fcopy_onchannelcallback(void *context)
+{
+	struct vmbus_channel *channel = context;
+	u32 recvlen;
+	u64 requestid;
+	struct hv_fcopy_hdr *fcopy_msg;
+	struct icmsg_hdr *icmsghdr;
+	struct icmsg_negotiate *negop = NULL;
+	int util_fw_version;
+	int fcopy_srv_version;
+
+	if (fcopy_transaction.active) {
+		/*
+		 * We will defer processing this callback once
+		 * the current transaction is complete.
+		 */
+		fcopy_transaction.fcopy_context = context;
+		return;
+	}
+
+	vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 2, &recvlen,
+			 &requestid);
+	if (recvlen <= 0)
+		return;
+
+	icmsghdr = (struct icmsg_hdr *)&recv_buffer[
+			sizeof(struct vmbuspipe_hdr)];
+	if (icmsghdr->icmsgtype == ICMSGTYPE_NEGOTIATE) {
+		util_fw_version = UTIL_FW_VERSION;
+		fcopy_srv_version = WIN8_SRV_VERSION;
+		vmbus_prep_negotiate_resp(icmsghdr, negop, recv_buffer,
+				util_fw_version, fcopy_srv_version);
+	} else {
+		fcopy_msg = (struct hv_fcopy_hdr *)&recv_buffer[
+				sizeof(struct vmbuspipe_hdr) +
+				sizeof(struct icmsg_hdr)];
+
+		/*
+		 * Stash away this global state for completing the
+		 * transaction; note transactions are serialized.
+		 */
+
+		fcopy_transaction.active = true;
+		fcopy_transaction.recv_len = recvlen;
+		fcopy_transaction.recv_channel = channel;
+		fcopy_transaction.recv_req_id = requestid;
+		fcopy_transaction.fcopy_msg = fcopy_msg;
+
+		/*
+		 * Send the information to the user-level daemon.
+		 */
+		fcopy_send_data();
+		schedule_delayed_work(&fcopy_work, 5*HZ);
+		return;
+	}
+	icmsghdr->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE;
+	vmbus_sendpacket(channel, recv_buffer, recvlen, requestid,
+			VM_PKT_DATA_INBAND, 0);
+}
+
+/*
+ * Create a char device that can support read/write for passing
+ * the payload.
+ */
+
+static ssize_t fcopy_read(struct file *file, char __user *buf,
+		size_t count, loff_t *ppos)
+{
+	void *src;
+	size_t copy_size;
+	int operation;
+
+	/*
+	 * Wait until there is something to be read.
+	 */
+	if (down_interruptible(&fcopy_transaction.read_sema))
+		return -EINTR;
+
+	/*
+	 * The channel may be rescinded and in this case, we will wakeup the
+	 * the thread blocked on the semaphore and we will use the opened
+	 * state to correctly handle this case.
+	 */
+	if (!opened)
+		return -ENODEV;
+
+	operation = fcopy_transaction.fcopy_msg->operation;
+
+	if (operation == START_FILE_COPY) {
+		src = &fcopy_transaction.message;
+		copy_size = sizeof(struct hv_start_fcopy);
+		if (count < copy_size)
+			return 0;
+	} else {
+		src = fcopy_transaction.fcopy_msg;
+		copy_size = sizeof(struct hv_do_fcopy);
+		if (count < copy_size)
+			return 0;
+	}
+	if (copy_to_user(buf, src, copy_size))
+		return -EFAULT;
+
+	return copy_size;
+}
+
+static ssize_t fcopy_write(struct file *file, const char __user *buf,
+			size_t count, loff_t *ppos)
+{
+	int response = 0;
+
+	if (count != sizeof(int))
+		return -EINVAL;
+
+	if (copy_from_user(&response, buf, sizeof(int)))
+		return -EFAULT;
+
+	if (in_hand_shake) {
+		if (fcopy_handle_handshake(response))
+			return -EINVAL;
+		return sizeof(int);
+	}
+
+	/*
+	 * Complete the transaction by forwarding the result
+	 * to the host. But first, cancel the timeout.
+	 */
+	if (cancel_delayed_work_sync(&fcopy_work))
+		fcopy_respond_to_host(response);
+
+	return sizeof(int);
+}
+
+static int fcopy_open(struct inode *inode, struct file *f)
+{
+	/*
+	 * The user level daemon that will open this device is
+	 * really an extension of this driver. We can have only
+	 * active open at a time.
+	 */
+	if (opened)
+		return -EBUSY;
+
+	/*
+	 * The daemon is alive; setup the state.
+	 */
+	opened = true;
+	return 0;
+}
+
+static int fcopy_release(struct inode *inode, struct file *f)
+{
+	/*
+	 * The daemon has exited; reset the state.
+	 */
+	in_hand_shake = true;
+	opened = false;
+	return 0;
+}
+
+
+static const struct file_operations fcopy_fops = {
+	.read           = fcopy_read,
+	.write          = fcopy_write,
+	.release	= fcopy_release,
+	.open		= fcopy_open,
+};
+
+static struct miscdevice fcopy_misc = {
+	.minor          = MISC_DYNAMIC_MINOR,
+	.name           = "vmbus/hv_fcopy",
+	.fops           = &fcopy_fops,
+};
+
+static int fcopy_dev_init(void)
+{
+	return misc_register(&fcopy_misc);
+}
+
+static void fcopy_dev_deinit(void)
+{
+
+	/*
+	 * The device is going away - perhaps because the
+	 * host has rescinded the channel. Setup state so that
+	 * user level daemon can gracefully exit if it is blocked
+	 * on the read semaphore.
+	 */
+	opened = false;
+	/*
+	 * Signal the semaphore as the device is
+	 * going away.
+	 */
+	up(&fcopy_transaction.read_sema);
+	misc_deregister(&fcopy_misc);
+}
+
+int hv_fcopy_init(struct hv_util_service *srv)
+{
+	recv_buffer = srv->recv_buffer;
+
+	/*
+	 * When this driver loads, the user level daemon that
+	 * processes the host requests may not yet be running.
+	 * Defer processing channel callbacks until the daemon
+	 * has registered.
+	 */
+	fcopy_transaction.active = true;
+	sema_init(&fcopy_transaction.read_sema, 0);
+
+	return fcopy_dev_init();
+}
+
+void hv_fcopy_deinit(void)
+{
+	cancel_delayed_work_sync(&fcopy_work);
+	fcopy_dev_deinit();
+}
diff --git a/drivers/hv/hv_kvp.c b/drivers/hv/hv_kvp.c
index 09988b289622..ea852537307e 100644
--- a/drivers/hv/hv_kvp.c
+++ b/drivers/hv/hv_kvp.c
@@ -113,7 +113,7 @@ kvp_register(int reg_value)
 		kvp_msg->kvp_hdr.operation = reg_value;
 		strcpy(version, HV_DRV_VERSION);
 		msg->len = sizeof(struct hv_kvp_msg);
-		cn_netlink_send(msg, 0, GFP_ATOMIC);
+		cn_netlink_send(msg, 0, 0, GFP_ATOMIC);
 		kfree(msg);
 	}
 }
@@ -435,7 +435,7 @@ kvp_send_key(struct work_struct *dummy)
 	}
 
 	msg->len = sizeof(struct hv_kvp_msg);
-	cn_netlink_send(msg, 0, GFP_ATOMIC);
+	cn_netlink_send(msg, 0, 0, GFP_ATOMIC);
 	kfree(msg);
 
 	return;
diff --git a/drivers/hv/hv_snapshot.c b/drivers/hv/hv_snapshot.c
index 0c3546224376..34f14fddb666 100644
--- a/drivers/hv/hv_snapshot.c
+++ b/drivers/hv/hv_snapshot.c
@@ -98,7 +98,7 @@ static void vss_send_op(struct work_struct *dummy)
 	vss_msg->vss_hdr.operation = op;
 	msg->len = sizeof(struct hv_vss_msg);
 
-	cn_netlink_send(msg, 0, GFP_ATOMIC);
+	cn_netlink_send(msg, 0, 0, GFP_ATOMIC);
 	kfree(msg);
 
 	return;
diff --git a/drivers/hv/hv_util.c b/drivers/hv/hv_util.c
index 62dfd246b948..dd761806f0e8 100644
--- a/drivers/hv/hv_util.c
+++ b/drivers/hv/hv_util.c
@@ -28,6 +28,7 @@
 #include <linux/reboot.h>
 #include <linux/hyperv.h>
 
+#include "hyperv_vmbus.h"
 
 #define SD_MAJOR	3
 #define SD_MINOR	0
@@ -82,6 +83,12 @@ static struct hv_util_service util_vss = {
 	.util_deinit = hv_vss_deinit,
 };
 
+static struct hv_util_service util_fcopy = {
+	.util_cb = hv_fcopy_onchannelcallback,
+	.util_init = hv_fcopy_init,
+	.util_deinit = hv_fcopy_deinit,
+};
+
 static void perform_shutdown(struct work_struct *dummy)
 {
 	orderly_poweroff(true);
@@ -401,6 +408,10 @@ static const struct hv_vmbus_device_id id_table[] = {
 	{ HV_VSS_GUID,
 	  .driver_data = (unsigned long)&util_vss
 	},
+	/* File copy GUID */
+	{ HV_FCOPY_GUID,
+	  .driver_data = (unsigned long)&util_fcopy
+	},
 	{ },
 };
 
diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
index e05517616a06..860134da8039 100644
--- a/drivers/hv/hyperv_vmbus.h
+++ b/drivers/hv/hyperv_vmbus.h
@@ -559,8 +559,8 @@ int hv_ringbuffer_init(struct hv_ring_buffer_info *ring_info, void *buffer,
 void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info);
 
 int hv_ringbuffer_write(struct hv_ring_buffer_info *ring_info,
-		    struct scatterlist *sglist,
-		    u32 sgcount, bool *signal);
+		    struct kvec *kv_list,
+		    u32 kv_count, bool *signal);
 
 int hv_ringbuffer_peek(struct hv_ring_buffer_info *ring_info, void *buffer,
 		   u32 buflen);
@@ -669,5 +669,9 @@ int vmbus_set_event(struct vmbus_channel *channel);
 
 void vmbus_on_event(unsigned long data);
 
+int hv_fcopy_init(struct hv_util_service *);
+void hv_fcopy_deinit(void);
+void hv_fcopy_onchannelcallback(void *);
+
 
 #endif /* _HYPERV_VMBUS_H */
diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c
index 26c93cf9f6be..15db66b74141 100644
--- a/drivers/hv/ring_buffer.c
+++ b/drivers/hv/ring_buffer.c
@@ -26,6 +26,7 @@
 #include <linux/kernel.h>
 #include <linux/mm.h>
 #include <linux/hyperv.h>
+#include <linux/uio.h>
 
 #include "hyperv_vmbus.h"
 
@@ -387,23 +388,20 @@ void hv_ringbuffer_cleanup(struct hv_ring_buffer_info *ring_info)
  *
  */
 int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info,
-		    struct scatterlist *sglist, u32 sgcount, bool *signal)
+		    struct kvec *kv_list, u32 kv_count, bool *signal)
 {
 	int i = 0;
 	u32 bytes_avail_towrite;
 	u32 bytes_avail_toread;
 	u32 totalbytes_towrite = 0;
 
-	struct scatterlist *sg;
 	u32 next_write_location;
 	u32 old_write;
 	u64 prev_indices = 0;
 	unsigned long flags;
 
-	for_each_sg(sglist, sg, sgcount, i)
-	{
-		totalbytes_towrite += sg->length;
-	}
+	for (i = 0; i < kv_count; i++)
+		totalbytes_towrite += kv_list[i].iov_len;
 
 	totalbytes_towrite += sizeof(u64);
 
@@ -427,12 +425,11 @@ int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info,
 
 	old_write = next_write_location;
 
-	for_each_sg(sglist, sg, sgcount, i)
-	{
+	for (i = 0; i < kv_count; i++) {
 		next_write_location = hv_copyto_ringbuffer(outring_info,
 						     next_write_location,
-						     sg_virt(sg),
-						     sg->length);
+						     kv_list[i].iov_base,
+						     kv_list[i].iov_len);
 	}
 
 	/* Set previous packet start */
diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
index 3f0a95290e14..8e53a3c2607e 100644
--- a/drivers/hv/vmbus_drv.c
+++ b/drivers/hv/vmbus_drv.c
@@ -43,6 +43,12 @@ static struct tasklet_struct msg_dpc;
 static struct completion probe_event;
 static int irq;
 
+struct resource hyperv_mmio = {
+	.name  = "hyperv mmio",
+	.flags = IORESOURCE_MEM,
+};
+EXPORT_SYMBOL_GPL(hyperv_mmio);
+
 static int vmbus_exists(void)
 {
 	if (hv_acpi_dev == NULL)
@@ -843,18 +849,21 @@ void vmbus_device_unregister(struct hv_device *device_obj)
 
 
 /*
- * VMBUS is an acpi enumerated device. Get the the IRQ information
- * from DSDT.
+ * VMBUS is an acpi enumerated device. Get the the information we
+ * need from DSDT.
  */
 
-static acpi_status vmbus_walk_resources(struct acpi_resource *res, void *irq)
+static acpi_status vmbus_walk_resources(struct acpi_resource *res, void *ctx)
 {
+	switch (res->type) {
+	case ACPI_RESOURCE_TYPE_IRQ:
+		irq = res->data.irq.interrupts[0];
+		break;
 
-	if (res->type == ACPI_RESOURCE_TYPE_IRQ) {
-		struct acpi_resource_irq *irqp;
-		irqp = &res->data.irq;
-
-		*((unsigned int *)irq) = irqp->interrupts[0];
+	case ACPI_RESOURCE_TYPE_ADDRESS64:
+		hyperv_mmio.start = res->data.address64.minimum;
+		hyperv_mmio.end = res->data.address64.maximum;
+		break;
 	}
 
 	return AE_OK;
@@ -863,18 +872,34 @@ static acpi_status vmbus_walk_resources(struct acpi_resource *res, void *irq)
 static int vmbus_acpi_add(struct acpi_device *device)
 {
 	acpi_status result;
+	int ret_val = -ENODEV;
 
 	hv_acpi_dev = device;
 
 	result = acpi_walk_resources(device->handle, METHOD_NAME__CRS,
-					vmbus_walk_resources, &irq);
+					vmbus_walk_resources, NULL);
 
-	if (ACPI_FAILURE(result)) {
-		complete(&probe_event);
-		return -ENODEV;
+	if (ACPI_FAILURE(result))
+		goto acpi_walk_err;
+	/*
+	 * The parent of the vmbus acpi device (Gen2 firmware) is the VMOD that
+	 * has the mmio ranges. Get that.
+	 */
+	if (device->parent) {
+		result = acpi_walk_resources(device->parent->handle,
+					METHOD_NAME__CRS,
+					vmbus_walk_resources, NULL);
+
+		if (ACPI_FAILURE(result))
+			goto acpi_walk_err;
+		if (hyperv_mmio.start && hyperv_mmio.end)
+			request_resource(&iomem_resource, &hyperv_mmio);
 	}
+	ret_val = 0;
+
+acpi_walk_err:
 	complete(&probe_event);
-	return 0;
+	return ret_val;
 }
 
 static const struct acpi_device_id vmbus_acpi_device_ids[] = {