[PATCH 15/21] Drivers: hv: fcopy: convert to hv_utils_transport
From: K. Y. Srinivasan
Date: Sat Apr 11 2015 - 19:54:50 EST
From: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Unify the code with the recently introduced hv_utils_transport. Netlink
communication is disabled for fcopy.
Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Tested-by: Alex Ng <alexng@xxxxxxxxxxxxx>
Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx>
---
drivers/hv/hv_fcopy.c | 194 ++++++++++++-------------------------------------
1 files changed, 46 insertions(+), 148 deletions(-)
diff --git a/drivers/hv/hv_fcopy.c b/drivers/hv/hv_fcopy.c
index d1475e6..6a8ec9f 100644
--- a/drivers/hv/hv_fcopy.c
+++ b/drivers/hv/hv_fcopy.c
@@ -19,17 +19,13 @@
#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
@@ -53,18 +49,19 @@ static struct {
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 void fcopy_send_data(void);
static void fcopy_respond_to_host(int error);
+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;
static void fcopy_timeout_func(struct work_struct *dummy)
{
@@ -78,17 +75,6 @@ static void fcopy_timeout_func(struct work_struct *dummy)
if (fcopy_transaction.state > HVUTIL_READY)
fcopy_transaction.state = HVUTIL_READY;
- /* 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))
- ;
-
hv_poll_channel(fcopy_transaction.fcopy_context,
hv_fcopy_onchannelcallback);
}
@@ -115,11 +101,13 @@ static int fcopy_handle_handshake(u32 version)
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;
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
@@ -134,26 +122,39 @@ static void fcopy_send_data(void)
switch (operation) {
case START_FILE_COPY:
- memset(smsg_out, 0, sizeof(struct hv_start_fcopy));
- smsg_out->hdr.operation = operation;
+ out_len = sizeof(struct hv_start_fcopy);
+ memset(&smsg_out, 0, out_len);
+ 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;
+ 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;
+ }
+ }
return;
}
@@ -255,8 +256,8 @@ void hv_fcopy_onchannelcallback(void *context)
/*
* Send the information to the user-level daemon.
*/
+ schedule_work(&fcopy_send_work);
schedule_delayed_work(&fcopy_timeout_work, 5*HZ);
- fcopy_send_data();
return;
}
icmsghdr->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE;
@@ -264,69 +265,16 @@ void hv_fcopy_onchannelcallback(void *context)
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 state to
- * correctly handle this case.
- */
- if (fcopy_transaction.state != HVUTIL_HOSTMSG_RECEIVED)
- 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;
-
- fcopy_transaction.state = HVUTIL_USERSPACE_REQ;
-
- 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) {
- if (fcopy_handle_handshake(response))
- return -EINVAL;
- return sizeof(int);
- }
+ if (fcopy_transaction.state == HVUTIL_DEVICE_INIT)
+ return fcopy_handle_handshake(*val);
if (fcopy_transaction.state != HVUTIL_USERSPACE_REQ)
return -EINVAL;
@@ -337,78 +285,24 @@ static ssize_t fcopy_write(struct file *file, const char __user *buf,
*/
if (cancel_delayed_work_sync(&fcopy_timeout_work)) {
fcopy_transaction.state = HVUTIL_USERSPACE_RECV;
- fcopy_respond_to_host(response);
+ fcopy_respond_to_host(*val);
fcopy_transaction.state = HVUTIL_READY;
hv_poll_channel(fcopy_transaction.fcopy_context,
hv_fcopy_onchannelcallback);
}
- 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 (fcopy_transaction.state != HVUTIL_DEVICE_INIT)
- return -EBUSY;
-
return 0;
}
-/* XXX: there are still some tricky corner cases, e.g.,
- * In an 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.
- */
-static int fcopy_release(struct inode *inode, struct file *f)
+static void fcopy_on_reset(void)
{
/*
* The daemon has exited; reset the state.
*/
fcopy_transaction.state = HVUTIL_DEVICE_INIT;
- if (cancel_delayed_work_sync(&fcopy_timeout_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 = {
- .owner = THIS_MODULE,
- .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)
-{
-
- /*
- * 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)
@@ -422,14 +316,18 @@ int hv_fcopy_init(struct hv_util_service *srv)
* has registered.
*/
fcopy_transaction.state = HVUTIL_DEVICE_INIT;
- sema_init(&fcopy_transaction.read_sema, 0);
- return fcopy_dev_init();
+ hvt = hvutil_transport_init(fcopy_devname, 0, 0,
+ fcopy_on_msg, fcopy_on_reset);
+ if (!hvt)
+ return -EFAULT;
+
+ return 0;
}
void hv_fcopy_deinit(void)
{
fcopy_transaction.state = HVUTIL_DEVICE_DYING;
cancel_delayed_work_sync(&fcopy_timeout_work);
- fcopy_dev_deinit();
+ hvutil_transport_destroy(hvt);
}
--
1.7.4.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/