Implement the file copy service for Linux guests on Hyper-V. This permits the host to copy a file (over VMBUS) into the guest. This facility is part of "guest integration services" supported on the Windows platform. Here is a link that provides additional details on this functionality: http://technet.microsoft.com/en-us/library/dn464282.aspx In V1 version of the patch I have addressed comments from Olaf Hering <olaf@xxxxxxxxx> and Dan Carpenter <dan.carpenter@xxxxxxxxxx> In V2 version of this patch I did some minor cleanup (making some globals static). In V4 version of the patch I have addressed all of Olaf's most recent set of comments/concerns. In V5 version of the patch I had addressed Greg's most recent comments. I would like to thank Greg for suggesting that I use misc device; it has significantly simplified the code. In this version of the patch I have cleaned up error message based on Olaf's comments. I have also rebased the patch based on the current tip. Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx> --- drivers/hv/Makefile | 2 +- drivers/hv/hv_fcopy.c | 388 +++++++++++++++++++++++++++++++++++++++++++ drivers/hv/hv_util.c | 10 + include/linux/hyperv.h | 16 ++- include/uapi/linux/hyperv.h | 46 +++++ tools/hv/hv_fcopy_daemon.c | 195 ++++++++++++++++++++++ 6 files changed, 655 insertions(+), 2 deletions(-) create mode 100644 drivers/hv/hv_fcopy.c create mode 100644 tools/hv/hv_fcopy_daemon.c diff --git a/drivers/hv/Makefile b/drivers/hv/Makefile index 0a74b56..5e4dfa4 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/hv_fcopy.c b/drivers/hv/hv_fcopy.c new file mode 100644 index 0000000..15cf35c --- /dev/null +++ b/drivers/hv/hv_fcopy.c @@ -0,0 +1,388 @@ +/* + * An implementation of file copy service. + * + * Copyright (C) 2014, Microsoft, Inc. + * + * Author : K. Y. Srinivasan <ksrinivasan@xxxxxxxxxx> + * + * 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> + +#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 sizeof(int); +} + +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 *icmsghdrp; + 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. + */ + + buf_len = fcopy_transaction.recv_len; + channel = fcopy_transaction.recv_channel; + req_id = fcopy_transaction.recv_req_id; + + fcopy_transaction.active = false; + + icmsghdrp = (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; + + icmsghdrp->status = error; + icmsghdrp->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 *icmsghdrp; + 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; + + icmsghdrp = (struct icmsg_hdr *)&recv_buffer[ + sizeof(struct vmbuspipe_hdr)]; + if (icmsghdrp->icmsgtype == ICMSGTYPE_NEGOTIATE) { + util_fw_version = UTIL_FW_VERSION; + fcopy_srv_version = WIN8_SRV_VERSION; + vmbus_prep_negotiate_resp(icmsghdrp, 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; + } + icmsghdrp->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; + 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) + return fcopy_handle_handshake(response); + + /* + * 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); +} + +int fcopy_open(struct inode *inode, struct file *f) +{ + if (opened) + return -EBUSY; + + /* + * The daemon is alive; setup the state. + */ + opened = true; + return 0; +} + +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) +{ + 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_util.c b/drivers/hv/hv_util.c index 62dfd246..efc5e83 100644 --- a/drivers/hv/hv_util.c +++ b/drivers/hv/hv_util.c @@ -82,6 +82,12 @@ 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 +407,10 @@ 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/include/linux/hyperv.h b/include/linux/hyperv.h index fb66fba..d1ae9e4 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -30,7 +30,6 @@ #include <linux/types.h> #include <linux/scatterlist.h> #include <linux/list.h> -#include <linux/uuid.h> #include <linux/timer.h> #include <linux/workqueue.h> #include <linux/completion.h> @@ -1050,6 +1049,17 @@ void vmbus_driver_unregister(struct hv_driver *hv_driver); } /* + * Guest File Copy Service + * {34D14BE3-DEE4-41c8-9AE7-6B174977C192} + */ + +#define HV_FCOPY_GUID \ + .guid = { \ + 0xE3, 0x4B, 0xD1, 0x34, 0xE4, 0xDE, 0xC8, 0x41, \ + 0x9A, 0xE7, 0x6B, 0x17, 0x49, 0x77, 0xC1, 0x92 \ + } + +/* * Common header for Hyper-V ICs */ @@ -1160,6 +1170,10 @@ void hv_vss_onchannelcallback(void *); extern u64 hyperv_mmio_start; extern u64 hyperv_mmio_size; +int hv_fcopy_init(struct hv_util_service *); +void hv_fcopy_deinit(void); +void hv_fcopy_onchannelcallback(void *); + /* * Negotiated version with the Host. */ diff --git a/include/uapi/linux/hyperv.h b/include/uapi/linux/hyperv.h index 1861f8e..9beb7c9 100644 --- a/include/uapi/linux/hyperv.h +++ b/include/uapi/linux/hyperv.h @@ -25,6 +25,8 @@ #ifndef _UAPI_HYPERV_H #define _UAPI_HYPERV_H +#include <linux/uuid.h> + /* * Framework version for util services. */ @@ -94,6 +96,50 @@ struct hv_vss_msg { } __attribute__((packed)); /* + * Implementation of a host to guest copy facility. + */ + +#define FCOPY_VERSION_0 0 +#define FCOPY_CURRENT_VERSION FCOPY_VERSION_0 +#define W_MAX_PATH 260 + +enum hv_fcopy_op { + START_FILE_COPY = 0, + WRITE_TO_FILE, + COMPLETE_FCOPY, + CANCEL_FCOPY, +}; + +struct hv_fcopy_hdr { + __u32 operation; + uuid_le service_id0; /* currently unused */ + uuid_le service_id1; /* currently unused */ +} __attribute__((packed)); + +#define OVER_WRITE 0x1 +#define CREATE_PATH 0x2 + +struct hv_start_fcopy { + struct hv_fcopy_hdr hdr; + __u16 file_name[W_MAX_PATH]; + __u16 path_name[W_MAX_PATH]; + __u32 copy_flags; + __u64 file_size; +} __attribute__((packed)); + +/* + * The file is chunked into fragments. + */ +#define DATA_FRAGMENT (6 * 1024) + +struct hv_do_fcopy { + struct hv_fcopy_hdr hdr; + __u64 offset; + __u32 size; + __u8 data[DATA_FRAGMENT]; +}; + +/* * An implementation of HyperV key value pair (KVP) functionality for Linux. * * diff --git a/tools/hv/hv_fcopy_daemon.c b/tools/hv/hv_fcopy_daemon.c new file mode 100644 index 0000000..4ecc4fd --- /dev/null +++ b/tools/hv/hv_fcopy_daemon.c @@ -0,0 +1,195 @@ +/* + * An implementation of host to guest copy functionality for Linux. + * + * Copyright (C) 2014, Microsoft, Inc. + * + * Author : K. Y. Srinivasan <kys@xxxxxxxxxxxxx> + * + * 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. + */ + + +#include <sys/types.h> +#include <sys/socket.h> +#include <sys/poll.h> +#include <linux/types.h> +#include <linux/kdev_t.h> +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <string.h> +#include <ctype.h> +#include <errno.h> +#include <linux/hyperv.h> +#include <syslog.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <dirent.h> + +static int target_fd; +static char target_fname[W_MAX_PATH]; + +static int hv_start_fcopy(struct hv_start_fcopy *smsg) +{ + int error = HV_E_FAIL; + char *q, *p; + + /* + * If possile append a path seperator to the path. + */ + if (strlen((char *)smsg->path_name) < (W_MAX_PATH - 2)) + strcat((char *)smsg->path_name, "/"); + + p = (char *)smsg->path_name; + snprintf(target_fname, sizeof(target_fname), "%s/%s", + (char *)smsg->path_name, smsg->file_name); + + syslog(LOG_INFO, "Target file name: %s", target_fname); + /* + * Check to see if the path is already in place; if not, + * create if required. + */ + while ((q = strchr(p, '/')) != NULL) { + if (q == p) { + p++; + continue; + } + *q = '\0'; + if (access((char *)smsg->path_name, F_OK)) { + if (smsg->copy_flags & CREATE_PATH) { + if (mkdir((char *)smsg->path_name, 0755)) { + syslog(LOG_ERR, "Failed to create %s", + (char *)smsg->path_name); + goto done; + } + } else { + syslog(LOG_ERR, "Invalid path: %s", + (char *)smsg->path_name); + goto done; + } + } + p = q + 1; + *q = '/'; + } + + if (!access(target_fname, F_OK)) { + syslog(LOG_INFO, "File: %s exists", target_fname); + if (!smsg->copy_flags & OVER_WRITE) + goto done; + } + + target_fd = open(target_fname, O_RDWR | O_CREAT | O_CLOEXEC, 0744); + if (target_fd == -1) { + syslog(LOG_INFO, "Open Failed: %s", strerror(errno)); + goto done; + } + + error = 0; +done: + return error; +} + +static int hv_copy_data(struct hv_do_fcopy *cpmsg) +{ + ssize_t bytes_written; + + bytes_written = pwrite(target_fd, cpmsg->data, cpmsg->size, + cpmsg->offset); + + if (bytes_written != cpmsg->size) + return HV_E_FAIL; + + return 0; +} + +static int hv_copy_finished(void) +{ + close(target_fd); + return 0; +} +static int hv_copy_cancel(void) +{ + close(target_fd); + unlink(target_fname); + return 0; + +} + +int main(void) +{ + int fd, fcopy_fd, len; + int error; + int version = FCOPY_CURRENT_VERSION; + char *buffer[4096 * 2]; + struct hv_fcopy_hdr *in_msg; + + if (daemon(1, 0)) { + syslog(LOG_ERR, "daemon() failed; error: %s", strerror(errno)); + exit(EXIT_FAILURE); + } + + openlog("HV_FCOPY", 0, LOG_USER); + syslog(LOG_INFO, "HV_FCOPY starting; pid is:%d", getpid()); + + fcopy_fd = open("/dev/vmbus/hv_fcopy", O_RDWR); + + if (fcopy_fd < 0) { + syslog(LOG_ERR, "open /dev/vmbus/hv_fcopy failed; error: %d %s", + errno, strerror(errno)); + exit(EXIT_FAILURE); + } + + /* + * Register with the kernel. + */ + if ((write(fcopy_fd, &version, sizeof(int))) != sizeof(int)) { + syslog(LOG_ERR, "Registration failed: %s", strerror(errno)); + exit(EXIT_FAILURE); + } + + while (1) { + /* + * In this loop we process fcopy messages after the + * handshake is complete. + */ + len = pread(fcopy_fd, buffer, (4096 * 2), 0); + if (len < 0) { + syslog(LOG_ERR, "pread failed: %s", strerror(errno)); + exit(EXIT_FAILURE); + } + in_msg = (struct hv_fcopy_hdr *)buffer; + + switch (in_msg->operation) { + case START_FILE_COPY: + error = hv_start_fcopy((struct hv_start_fcopy *)in_msg); + break; + case WRITE_TO_FILE: + error = hv_copy_data((struct hv_do_fcopy *)in_msg); + break; + case COMPLETE_FCOPY: + error = hv_copy_finished(); + break; + case CANCEL_FCOPY: + error = hv_copy_cancel(); + break; + + default: + syslog(LOG_ERR, "Unknown operation: %d", + in_msg->operation); + + } + + if (pwrite(fcopy_fd, &error, sizeof(int), 0) != sizeof(int)) { + syslog(LOG_ERR, "pwrite failed: %s", strerror(errno)); + exit(EXIT_FAILURE); + } + } +} -- 1.7.4.1 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
