#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"
+#include "hv_utils_transport.h"
#define WIN8_SRV_MAJOR 1
#define WIN8_SRV_MINOR 1
* 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 state; /* hvutil_device_state */
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 void fcopy_send_data(struct work_struct *dummy);
+static void fcopy_timeout_func(struct work_struct *dummy);
+static DECLARE_DELAYED_WORK(fcopy_timeout_work, fcopy_timeout_func);
+static DECLARE_WORK(fcopy_send_work, fcopy_send_data);
+static const char fcopy_devname[] = "vmbus/hv_fcopy";
static u8 *recv_buffer;
+static struct hvutil_transport *hvt;
+/*
+ * This state maintains the version number registered by the daemon.
+ */
+static int dm_reg_value;
-static void fcopy_work_func(struct work_struct *dummy)
+static void fcopy_timeout_func(struct work_struct *dummy)
{
/*
* If the timer fires, the user-mode component has not responded;
*/
fcopy_respond_to_host(HV_E_FAIL);
- /* In the case the user-space daemon crashes, hangs or is killed, we
- * need to down the semaphore, otherwise, after the daemon starts next
- * time, the obsolete data in fcopy_transaction.message or
- * fcopy_transaction.fcopy_msg will be used immediately.
- *
- * NOTE: fcopy_read() happens to get the semaphore (very rare)? We're
- * still OK, because we've reported the failure to the host.
- */
- if (down_trylock(&fcopy_transaction.read_sema))
- ;
+ /* Transaction is finished, reset the state. */
+ if (fcopy_transaction.state > HVUTIL_READY)
+ fcopy_transaction.state = HVUTIL_READY;
+ hv_poll_channel(fcopy_transaction.fcopy_context,
+ hv_fcopy_onchannelcallback);
}
static int fcopy_handle_handshake(u32 version)
{
+ u32 our_ver = FCOPY_CURRENT_VERSION;
+
switch (version) {
- case FCOPY_CURRENT_VERSION:
+ case FCOPY_VERSION_0:
+ /* Daemon doesn't expect us to reply */
+ dm_reg_value = version;
+ break;
+ case FCOPY_VERSION_1:
+ /* Daemon expects us to reply with our own version */
+ if (hvutil_transport_send(hvt, &our_ver, sizeof(our_ver)))
+ return -EFAULT;
+ dm_reg_value = version;
break;
default:
/*
*/
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;
+ pr_debug("FCP: userspace daemon ver. %d registered\n", version);
+ fcopy_transaction.state = HVUTIL_READY;
+ hv_poll_channel(fcopy_transaction.fcopy_context,
+ hv_fcopy_onchannelcallback);
return 0;
}
-static void fcopy_send_data(void)
+static void fcopy_send_data(struct work_struct *dummy)
{
- struct hv_start_fcopy *smsg_out = &fcopy_transaction.message;
+ struct hv_start_fcopy *smsg_out = NULL;
int operation = fcopy_transaction.fcopy_msg->operation;
struct hv_start_fcopy *smsg_in;
+ void *out_src;
+ int rc, out_len;
/*
* The strings sent from the host are encoded in
switch (operation) {
case START_FILE_COPY:
- memset(smsg_out, 0, sizeof(struct hv_start_fcopy));
+ out_len = sizeof(struct hv_start_fcopy);
+ smsg_out = kzalloc(sizeof(*smsg_out), GFP_KERNEL);
+ if (!smsg_out)
+ return;
+
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);
+ (__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);
+ (__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;
+ out_src = smsg_out;
break;
default:
+ out_src = fcopy_transaction.fcopy_msg;
+ out_len = fcopy_transaction.recv_len;
break;
}
- up(&fcopy_transaction.read_sema);
+
+ fcopy_transaction.state = HVUTIL_USERSPACE_REQ;
+ rc = hvutil_transport_send(hvt, out_src, out_len);
+ if (rc) {
+ pr_debug("FCP: failed to communicate to the daemon: %d\n", rc);
+ if (cancel_delayed_work_sync(&fcopy_timeout_work)) {
+ fcopy_respond_to_host(HV_E_FAIL);
+ fcopy_transaction.state = HVUTIL_READY;
+ }
+ }
+ kfree(smsg_out);
+
return;
}
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)];
int util_fw_version;
int fcopy_srv_version;
- if (fcopy_transaction.active) {
+ if (fcopy_transaction.state > HVUTIL_READY) {
/*
* We will defer processing this callback once
* the current transaction is complete.
fcopy_transaction.fcopy_context = context;
return;
}
+ fcopy_transaction.fcopy_context = NULL;
vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 2, &recvlen,
&requestid);
* 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;
+ if (fcopy_transaction.state < HVUTIL_READY) {
+ /* Userspace is not registered yet */
+ fcopy_respond_to_host(HV_E_FAIL);
+ return;
+ }
+ fcopy_transaction.state = HVUTIL_HOSTMSG_RECEIVED;
+
/*
* Send the information to the user-level daemon.
*/
- schedule_delayed_work(&fcopy_work, 5*HZ);
- fcopy_send_data();
+ schedule_work(&fcopy_send_work);
+ schedule_delayed_work(&fcopy_timeout_work, 5*HZ);
return;
}
icmsghdr->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE;
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)
+/* Callback when data is received from userspace */
+static int fcopy_on_msg(void *msg, int len)
{
- int response = 0;
+ int *val = (int *)msg;
- if (count != sizeof(int))
+ if (len != sizeof(int))
return -EINVAL;
- if (copy_from_user(&response, buf, sizeof(int)))
- return -EFAULT;
+ if (fcopy_transaction.state == HVUTIL_DEVICE_INIT)
+ return fcopy_handle_handshake(*val);
- if (in_hand_shake) {
- if (fcopy_handle_handshake(response))
- return -EINVAL;
- return sizeof(int);
- }
+ if (fcopy_transaction.state != HVUTIL_USERSPACE_REQ)
+ return -EINVAL;
/*
* 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;
+ if (cancel_delayed_work_sync(&fcopy_timeout_work)) {
+ fcopy_transaction.state = HVUTIL_USERSPACE_RECV;
+ fcopy_respond_to_host(*val);
+ fcopy_transaction.state = HVUTIL_READY;
+ hv_poll_channel(fcopy_transaction.fcopy_context,
+ hv_fcopy_onchannelcallback);
+ }
- /*
- * The daemon is alive; setup the state.
- */
- opened = true;
return 0;
}
-/* XXX: there are still some tricky corner cases, e.g.,
- * 1) In a SMP guest, when fcopy_release() runs between
- * schedule_delayed_work() and fcopy_send_data(), there is
- * still a chance an obsolete message will be queued.
- *
- * 2) When the fcopy daemon is running, if we unload the driver,
- * we'll notice a kernel oops when we kill the daemon later.
- */
-static int fcopy_release(struct inode *inode, struct file *f)
+static void fcopy_on_reset(void)
{
/*
* The daemon has exited; reset the state.
*/
- in_hand_shake = true;
- opened = false;
+ fcopy_transaction.state = HVUTIL_DEVICE_INIT;
- if (cancel_delayed_work_sync(&fcopy_work)) {
- /* We haven't up()-ed the semaphore(very rare)? */
- if (down_trylock(&fcopy_transaction.read_sema))
- ;
+ if (cancel_delayed_work_sync(&fcopy_timeout_work))
fcopy_respond_to_host(HV_E_FAIL);
- }
- 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)
* Defer processing channel callbacks until the daemon
* has registered.
*/
- fcopy_transaction.active = true;
- sema_init(&fcopy_transaction.read_sema, 0);
+ fcopy_transaction.state = HVUTIL_DEVICE_INIT;
+
+ hvt = hvutil_transport_init(fcopy_devname, 0, 0,
+ fcopy_on_msg, fcopy_on_reset);
+ if (!hvt)
+ return -EFAULT;
- return fcopy_dev_init();
+ return 0;
}
void hv_fcopy_deinit(void)
{
- cancel_delayed_work_sync(&fcopy_work);
- fcopy_dev_deinit();
+ fcopy_transaction.state = HVUTIL_DEVICE_DYING;
+ cancel_delayed_work_sync(&fcopy_timeout_work);
+ hvutil_transport_destroy(hvt);
}
Code Review / kvmfornfv.git / blobdiff