From 01325476d6e46185031be4a9bc6443832dbc807c Mon Sep 17 00:00:00 2001 From: "K. Y. Srinivasan" Date: Sun, 16 Feb 2014 11:34:30 -0800 Subject: Drivers: hv: Implement the file copy service 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 and Dan Carpenter 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 V6 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. In this version of the patch, I have addressed the latest comments from Greg. Signed-off-by: K. Y. Srinivasan Signed-off-by: Greg Kroah-Hartman --- tools/hv/hv_fcopy_daemon.c | 195 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 195 insertions(+) create mode 100644 tools/hv/hv_fcopy_daemon.c (limited to 'tools/hv') diff --git a/tools/hv/hv_fcopy_daemon.c b/tools/hv/hv_fcopy_daemon.c new file mode 100644 index 000000000000..4ecc4fd0bc1b --- /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 + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +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); + } + } +} -- cgit v1.2.3