From: Kyle Hale <kh@u.northwestern.edu>
Date: Sat, 28 Jul 2012 20:46:05 +0000 (-0500)
Subject: repurpose v3_ctrl.c as a utility library for palacios userspace progs
X-Git-Url: http://v3vee.org/palacios/gitweb/gitweb.cgi?p=palacios.git;a=commitdiff_plain;h=008fdde9a6a6ec65b7647d9eec487448094d7f18

repurpose v3_ctrl.c as a utility library for palacios userspace progs

I've taken some common idioms used in a lot of the userspace utilities
and put them in a (for now, static) library that all programs can utilize.
One example: when running an ioctl, it's no longer necessary to open the vm device,
close it, etc. This is taken care of by v3_vm_ioctl.
This should give us some more code sharing and make the userspace utilities quicker to write and a bit smaller.
For now, I've modified v3_free, v3_launch, v3_stop, and v3_create to use this library,
so you can look to those for examples.
---

diff --git a/linux_usr/Makefile b/linux_usr/Makefile
index 888e956..dc1ab05 100644
--- a/linux_usr/Makefile
+++ b/linux_usr/Makefile
@@ -62,7 +62,7 @@ COPIED_EXECS = v3_x0vncserver
 #
 # Libraries that we need to build
 #
-LIBS = libv3_user_host_dev.a libv3_user_keyed_stream.a
+LIBS = libv3_user_host_dev.a libv3_user_keyed_stream.a libv3_ctrl.a
 
 BUILD_EXECS = $(BASE_EXECS) $(EXAMPLE_EXECS) $(EXPERIMENTAL_EXECS) 
 BUILD_LIBS = $(LIBS)
@@ -82,11 +82,16 @@ AR = ar
 all: $(BUILD_EXECS) $(BUILD_LIBS) $(COPIED_EXECS)
 
 
+libv3_ctrl.a : v3_ctrl.c v3_ctrl.h
+	$(CC) $(CFLAGS) -I../linux_module -c v3_ctrl.c
+	$(AR) ruv libv3_ctrl.a v3_ctrl.o
+	rm -rf v3_ctrl.o 
+
 #
 # Most tools compile in a straightforward way
 #
-% :: %.c v3_ctrl.h
-	$(CC) $(CFLAGS) $< -o $@
+% :: %.c v3_ctrl.h libv3_ctrl.a
+	$(CC) $(CFLAGS) $< -lv3_ctrl -L. -o $@
 
 
 #
@@ -102,8 +107,8 @@ v3_cons: v3_cons.c
 v3_cons_sc: v3_cons_sc.c
 	$(CC) $(CFLAGS) $(CURSES_CFLAGS) $< -lcurses -o $@
 
-v3_create: v3_create.c ezxml.c
-	$(CC) $(CFLAGS) $^ -o $@
+v3_create: v3_create.c ezxml.c libv3_ctrl.a 
+	$(CC) $(CFLAGS) $^ -lv3_ctrl -L. -o $@
 
 
 
diff --git a/linux_usr/v3_create.c b/linux_usr/v3_create.c
index 02bb873..8131df3 100644
--- a/linux_usr/v3_create.c
+++ b/linux_usr/v3_create.c
@@ -17,33 +17,12 @@
 #include "v3_ctrl.h"
 #include "ezxml.h"
 
-struct cfg_value {
-    char * tag;
-    char * value;
-};
-
-struct xml_option {
-    char * tag;
-    ezxml_t location;
-    struct xml_option * next;
-};
-
-
-struct file_info {
-    int size;
-    char filename[2048];
-    char id[256];
-};
 
 #define MAX_FILES 256
 unsigned long long num_files = 0;
 struct file_info files[MAX_FILES];
 
 
-int read_file(int fd, int size, unsigned char * buf);
-
-
-
 int create_vm(char * vm_name, void * img_data, unsigned int img_size) {
     struct v3_guest_img guest_img;
     int v3_fd = 0;
@@ -55,16 +34,7 @@ int create_vm(char * vm_name, void * img_data, unsigned int img_size) {
     guest_img.guest_data = img_data;
     strncpy(guest_img.name, vm_name, 127);
 
-
-    v3_fd = open(v3_dev, O_RDONLY);
-
-    if (v3_fd == -1) {
-	printf("Error opening V3Vee control device\n");
-	return -1;
-    }
-
-    dev_idx = ioctl(v3_fd, V3_CREATE_GUEST, &guest_img); 
-
+    dev_idx = v3_dev_ioctl(V3_CREATE_GUEST, &guest_img); 
 
     if (dev_idx < 0) {
 	printf("Error (%d) creating VM\n", dev_idx);
@@ -72,10 +42,6 @@ int create_vm(char * vm_name, void * img_data, unsigned int img_size) {
     }
 
     printf("VM (%s) created at /dev/v3-vm%d\n", vm_name, dev_idx);
-
-    /* Close the file descriptor.  */ 
-    close(v3_fd); 
-
     return 0;
 }
 
@@ -103,7 +69,7 @@ int load_image(char * vm_name, char * filename) {
     // load guest image into user memory
     img_data = malloc(img_size);
 
-    read_file(guest_fd, img_size, img_data);
+    v3_read_file(guest_fd, img_size, img_data);
     
     close(guest_fd);
 
@@ -346,7 +312,7 @@ int build_image(char * vm_name, char * filename, struct cfg_value * cfg_vals, in
 		return -1;
 	    }
 
-	    read_file(fd, files[i].size, (unsigned char *)(guest_img_data + offset));
+	    v3_read_file(fd, files[i].size, (unsigned char *)(guest_img_data + offset));
 
 	    close(fd);
 
@@ -365,8 +331,6 @@ int build_image(char * vm_name, char * filename, struct cfg_value * cfg_vals, in
 
 
 
-
-
 int main(int argc, char** argv) {
     char * filename = NULL;
     char * name = NULL;
@@ -383,10 +347,8 @@ int main(int argc, char** argv) {
 	}
     }
 
-    if (argc - optind + 1 < 3) {
-	printf("usage: v3_create [-b] <guest_img> <vm name> [cfg options]\n");
-	return -1;
-    }
+    if (argc - optind + 1 < 3) 
+        v3_usage("[-b] <guest_img> <vm_name> [cfg options]\n");
 
     filename = argv[optind];
     name = argv[optind + 1];
@@ -436,28 +398,3 @@ int main(int argc, char** argv) {
 
     return 0; 
 } 
-
-
-
-int read_file(int fd, int size, unsigned char * buf) {
-    int left_to_read = size;
-    int have_read = 0;
-
-    while (left_to_read != 0) {
-	int bytes_read = read(fd, buf + have_read, left_to_read);
-
-	if (bytes_read <= 0) {
-	    break;
-	}
-
-	have_read += bytes_read;
-	left_to_read -= bytes_read;
-    }
-
-    if (left_to_read != 0) {
-	printf("Error could not finish reading file\n");
-	return -1;
-    }
-    
-    return 0;
-}
diff --git a/linux_usr/v3_ctrl.c b/linux_usr/v3_ctrl.c
index 984045b..0183a95 100644
--- a/linux_usr/v3_ctrl.c
+++ b/linux_usr/v3_ctrl.c
@@ -1,6 +1,7 @@
 /* 
- * V3 Control utility
+ * V3 Control Library
  * (c) Jack lange, 2010
+ *     Kyle Hale,  2012
  */
 
 
@@ -10,101 +11,142 @@
 #include <sys/ioctl.h> 
 #include <sys/stat.h> 
 #include <sys/types.h> 
+#include <sys/mman.h>
 #include <unistd.h> 
 #include <string.h>
  
 #include "v3_ctrl.h"
 
-int read_file(int fd, int size, unsigned char * buf);
 
-int main(int argc, char* argv[]) {
-    char * filename = argv[1];
-    char * name = argv[2];
-    int guest_fd = 0;
-    int v3_fd = 0;
-    struct v3_guest_img guest_img;
-    struct stat guest_stats;
- 
-    memset(&guest_img, 0, sizeof(struct v3_guest_img));
+/*
+ * create a file-backed memory region 
+ */
+void * v3_mmap_file (const char * filename, int prot, int flags) {
+    int fd;
+    struct stat st;
+    void * m;
+
+    fd = open(filename, O_RDONLY);
+    if (!fd) {
+        fprintf(stderr, "Error opening file for mapping: %s\n", filename);
+        return NULL;
+    }
 
-    if (argc <= 2) {
-	printf("usage: v3_ctrl <guest_img> <vm name>\n");
-	return -1;
+    fstat(fd, &st);
+
+    if ((m = mmap(NULL, st.st_size, prot, flags, fd, 0)) == MAP_FAILED) {
+        fprintf(stderr, "Error mapping file (%s)\n", filename);
+        close(fd);
+        return NULL;
     }
 
-    printf("Launching guest: %s\n", filename);
+    close(fd);
+    return m;
+}
 
-    guest_fd = open(filename, O_RDONLY); 
 
-    if (guest_fd == -1) {
-	printf("Error Opening guest image: %s\n", filename);
-	return -1;
+/*
+ * read a file into a buffer
+ */
+int v3_read_file (int fd, int size, unsigned char * buf) {
+    int left_to_read = size;
+    int have_read = 0;
+
+    while (left_to_read != 0) {
+	int bytes_read = read(fd, buf + have_read, left_to_read);
+
+	if (bytes_read <= 0) {
+	    break;
+	}
+
+	have_read += bytes_read;
+	left_to_read -= bytes_read;
     }
 
-    if (fstat(guest_fd, &guest_stats) == -1) {
-	printf("ERROR: Could not stat guest image file -- %s\n", filename);
+    if (left_to_read != 0) {
+	fprintf(stderr, "Error could not finish reading file\n");
 	return -1;
     }
-
-    
-    guest_img.size = guest_stats.st_size;
     
-    // load guest image into user memory
-    guest_img.guest_data = malloc(guest_img.size);
-    if (!guest_img.guest_data) {
-        printf("ERROR: Could not allocate memory for guest image\n");
+    return 0;
+}
+
+
+/*
+ * perform an ioctl on v3vee device
+ */
+int v3_dev_ioctl (int request, void * arg) {
+    int fd, ret;
+
+    fd = open(v3_dev, O_RDONLY);
+    if (fd == -1) {
+        fprintf(stderr, "Error opening V3Vee control device\n");
         return -1;
     }
 
-    read_file(guest_fd, guest_img.size, guest_img.guest_data);
-    
-    close(guest_fd);
+    ret = ioctl(fd, request, arg);
+
+    if (ret < 0) 
+        fprintf(stderr, "IOCTL error on V3Vee control device (%d)\n", ret);
 
-    printf("Loaded guest image. Launching to V3Vee\n");
-    
-    strncpy(guest_img.name, name, 127);
 
+    close(fd);
+    return ret;
+}
 
-    v3_fd = open(v3_dev, O_RDONLY);
 
-    if (v3_fd == -1) {
-	printf("Error opening V3Vee control device\n");
-	return -1;
+/*
+ * perform an ioctl on arbitrary VM device
+ */
+int v3_vm_ioctl (const char * filename, 
+                 int request, 
+                 void * arg) { 
+    int fd, ret;
+
+    fd = open(filename, O_RDONLY);
+    if (fd == -1) {
+        fprintf(stderr, "Error opening V3Vee VM device: %s\n", filename);
+        return -1;
     }
 
-    ioctl(v3_fd, V3_START_GUEST, &guest_img); 
+    ret = ioctl(fd, request, arg);
 
+    if (ret < 0) 
+        fprintf(stderr, "IOCTL error on device %s (%d)\n", filename, ret);
 
+    close(fd);
+    return ret;
+}
 
-    /* Close the file descriptor.  */ 
-    close(v3_fd); 
- 
 
+/* 
+ * launch a VM with VM device path
+ */
+int launch_vm (const char * filename) {
+    int err;
 
-    return 0; 
-} 
+    printf("Launching VM (%s)\n", filename);
+    err = v3_vm_ioctl(filename, V3_VM_LAUNCH, NULL);
 
+    if (err < 0) {
+        fprintf(stderr, "Error launching VM (%s)\n", filename);
+        return -1;
+    }
 
+    return 0;
+}
 
-int read_file(int fd, int size, unsigned char * buf) {
-    int left_to_read = size;
-    int have_read = 0;
 
-    while (left_to_read != 0) {
-	int bytes_read = read(fd, buf + have_read, left_to_read);
+/*
+ * stop a VM with VM device path
+ */
+int stop_vm (const char * filename) {
+    int err;
 
-	if (bytes_read <= 0) {
-	    break;
-	}
+    printf("Stopping VM (%s)\n", filename);
 
-	have_read += bytes_read;
-	left_to_read -= bytes_read;
-    }
+    if (v3_vm_ioctl(filename, V3_VM_STOP, NULL) < 0) 
+        return -1;
 
-    if (left_to_read != 0) {
-	printf("Error could not finish reading file\n");
-	return -1;
-    }
-    
     return 0;
 }
diff --git a/linux_usr/v3_ctrl.h b/linux_usr/v3_ctrl.h
index aae3af6..a210013 100644
--- a/linux_usr/v3_ctrl.h
+++ b/linux_usr/v3_ctrl.h
@@ -6,12 +6,16 @@
 #ifndef _v3_ctrl_h
 #define _v3_ctrl_h
 
+#include <stdio.h>
+#include <stdlib.h>
+#include "ezxml.h"
 
 /* Global Control IOCTLs */
 #define V3_CREATE_GUEST 12
 #define V3_FREE_GUEST 13
 
 #define V3_ADD_MEMORY 50
+#define V3_RESET_MEMORY 51
 #define V3_ADD_PCI_HW_DEV 55
 #define V3_ADD_PCI_USER_DEV 56
 
@@ -84,5 +88,46 @@ struct v3_hw_pci_dev {
     unsigned int func;
 } __attribute__((packed));
 
+#define V3VEE_STR "\n\n"                         \
+                  "The V3Vee Project (c) 2012\n" \
+                  "\thttp://v3vee.org\n"         \
+                  "\n\n"
+                   
+#define v3_usage(fmt, args...)                                \
+{                                                             \
+    printf(("\nUsage: %s " fmt V3VEE_STR), argv[0], ##args);  \
+    exit(0);                                                  \
+}
+
+
+int v3_dev_ioctl (int req, void * arg);
+int v3_vm_ioctl  (const char * filename,
+                  int req,
+                  void * arg);
+void * v3_mmap_file (const char * filename, int prot, int flags);
+int v3_read_file (int fd, int size, unsigned char * buf);
+
+int launch_vm (const char * filename);
+int stop_vm   (const char * filename);
+
+
+/* XML-related structs */
+struct cfg_value {
+    char * tag;
+    char * value;
+};
+
+struct xml_option {
+    char * tag;
+    ezxml_t location;
+    struct xml_option * next;
+};
+
+
+struct file_info {
+    int size;
+    char filename[2048];
+    char id[256];
+};
 
 #endif
diff --git a/linux_usr/v3_free.c b/linux_usr/v3_free.c
index 1aa4d7a..4746c21 100644
--- a/linux_usr/v3_free.c
+++ b/linux_usr/v3_free.c
@@ -3,50 +3,27 @@
  * (c) Jack lange, 2011
  */
 
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <fcntl.h> 
-#include <sys/ioctl.h> 
-#include <sys/stat.h> 
-#include <sys/types.h> 
-#include <unistd.h> 
 #include <string.h>
  
 #include "v3_ctrl.h"
 
 int main(int argc, char* argv[]) {
-    int vm_fd = 0;
     unsigned long vm_idx = 0;
     int ret;
 
-
-    if (argc <= 1) {
-	printf("usage: v3_free <vm-dev-idx>\n");
-	return -1;
-    }
+    if (argc <= 1) 
+	v3_usage("<vm-dev-idx>\n");
 
 
     vm_idx = strtol(argv[1], NULL, 0);
 
     printf("Freeing VM %d\n", vm_idx);
     
-    vm_fd = open("/dev/v3vee", O_RDONLY);
-
-    if (vm_fd == -1) {
-	printf("Error opening V3Vee VM device\n");
-	return -1;
-    }
-
-    ret = ioctl(vm_fd, V3_FREE_GUEST, vm_idx); 
-    if (ret < 0) {
-        printf("Error freeing VM %d\n", vm_idx);
+    if (v3_dev_ioctl(V3_FREE_GUEST, vm_idx) < 0) {
+        fprintf(stderr, "Error freeing VM %d\n", vm_idx);
         return -1;
     }
 
-    /* Close the file descriptor.  */ 
-    close(vm_fd); 
-
     return 0; 
 } 
 
diff --git a/linux_usr/v3_launch.c b/linux_usr/v3_launch.c
index 7419a6b..217d104 100644
--- a/linux_usr/v3_launch.c
+++ b/linux_usr/v3_launch.c
@@ -3,52 +3,16 @@
  * (c) Jack lange, 2010
  */
 
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <fcntl.h> 
-#include <sys/ioctl.h> 
-#include <sys/stat.h> 
-#include <sys/types.h> 
-#include <unistd.h> 
-#include <string.h>
- 
 #include "v3_ctrl.h"
 
 int main(int argc, char* argv[]) {
-    int vm_fd = 0;
     char * filename = argv[1];
-    int err;
-
-    if (argc <= 1) {
-	printf("usage: v3_launch <vm-device>\n");
-	return -1;
-    }
-
-    printf("Launching VM (%s)\n", filename);
-    
-    vm_fd = open(filename, O_RDONLY);
-
-    if (vm_fd == -1) {
-	printf("Error opening V3Vee VM device\n");
-	return -1;
-    }
-
-    err = ioctl(vm_fd, V3_VM_LAUNCH, NULL); 
-    if (err < 0) {
-        printf("Error launching VM\n");
-        return -1;
-    }
 
+    if (argc <= 1) 
+	v3_usage("<vm-device>\n");
 
 
-
-    /* Close the file descriptor.  */ 
-    close(vm_fd); 
- 
-
+    launch_vm(filename);
 
     return 0; 
 } 
-
-
diff --git a/linux_usr/v3_stop.c b/linux_usr/v3_stop.c
index adb69b1..86e5752 100644
--- a/linux_usr/v3_stop.c
+++ b/linux_usr/v3_stop.c
@@ -2,46 +2,19 @@
  * V3 Control utility
  * (c) Jack lange, 2010
  */
-
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <fcntl.h> 
-#include <sys/ioctl.h> 
-#include <sys/stat.h> 
-#include <sys/types.h> 
-#include <unistd.h> 
-#include <string.h>
- 
 #include "v3_ctrl.h"
 
 int main(int argc, char* argv[]) {
-    int vm_fd = 0;
     char * filename = argv[1];
 
-    if (argc <= 1) {
-	printf("usage: v3_stop <vm-device>\n");
-	return -1;
-    }
+    if (argc <= 1)
+        v3_usage("<vm-device>\n");
 
-    printf("Stopping VM (%s)\n", filename);
-    
-    vm_fd = open(filename, O_RDONLY);
-
-    if (vm_fd == -1) {
-	printf("Error opening V3Vee VM device\n");
-	return -1;
+    if (stop_vm(filename) < 0) {
+        fprintf(stderr, "Error stopping VM (%s)\n", filename);
+        return -1;
     }
 
-    ioctl(vm_fd, V3_VM_STOP, NULL); 
-
-
-
-    /* Close the file descriptor.  */ 
-    close(vm_fd); 
- 
-
-
     return 0; 
 }