Add dynamic VMM Driven/Guest Driven mode switch in VNET devices

[palacios.git] / palacios / src / devices / filedisk.c

diff --git a/palacios/src/devices/filedisk.c b/palacios/src/devices/filedisk.c
index d58c30f..b007ace 100644 (file)
--- a/palacios/src/devices/filedisk.c
+++ b/palacios/src/devices/filedisk.c
@@ -21,6 +21,7 @@
 #include <palacios/vmm_dev_mgr.h>
 
 #include <palacios/vmm_file.h>
+#include <palacios/vm_guest.h>
 
 #ifndef CONFIG_DEBUG_FILEDISK
 #undef PrintDebug
@@ -30,18 +31,56 @@
 struct disk_state {
     uint64_t capacity; // in bytes
 
-    int fd;
+    v3_file_t fd;
 };
 
 
+
+static int write_all(v3_file_t fd, char * buf, int offset, int length) {
+    int bytes_written = 0;
+    
+    PrintDebug("Writing %d bytes\n", length - bytes_written);
+    while (bytes_written < length) {
+       int tmp_bytes = v3_file_write(fd, buf + bytes_written, length - bytes_written, offset + bytes_written);
+       PrintDebug("Wrote %d bytes\n", tmp_bytes);
+       
+       if (tmp_bytes <= 0 ) {
+           PrintError("Write failed\n");
+           return -1;
+       }
+       
+       bytes_written += tmp_bytes;
+    }
+    
+    return 0;
+}
+
+
+static int read_all(v3_file_t fd, char * buf, int offset, int length) {
+    int bytes_read = 0;
+    
+    PrintDebug("Reading %d bytes\n", length - bytes_read);
+    while (bytes_read < length) {
+       int tmp_bytes = v3_file_read(fd, buf + bytes_read, length - bytes_read, offset + bytes_read);
+       PrintDebug("Read %d bytes\n", tmp_bytes);
+       
+       if (tmp_bytes <= 0) {
+           PrintError("Read failed\n");
+           return -1;
+       }
+       
+       bytes_read += tmp_bytes;
+    }
+    
+    return 0;
+}
+
 static int read(uint8_t * buf, uint64_t lba, uint64_t num_bytes, void * private_data) {
     struct disk_state * disk = (struct disk_state *)private_data;
 
     PrintDebug("Reading %d bytes from %p to %p\n", (uint32_t)num_bytes, (uint8_t *)(disk->disk_image + lba), buf);
 
-    V3_FileRead(disk->fd, lba, buf, num_bytes);
-
-    return 0;
+    return read_all(disk->fd, buf, lba, num_bytes);
 }
 
 
@@ -50,9 +89,7 @@ static int write(uint8_t * buf, uint64_t lba, uint64_t num_bytes, void * private
 
     PrintDebug("Writing %d bytes from %p to %p\n", (uint32_t)num_bytes,  buf, (uint8_t *)(disk->disk_image + lba));
 
-    V3_FileWrite(disk->fd, lba, buf, num_bytes);
-
-    return 0;
+    return write_all(disk->fd,  buf, lba, num_bytes);
 }
 
 
@@ -74,53 +111,74 @@ static struct v3_dev_blk_ops blk_ops = {
 
 
 
-static int disk_free(struct vm_device * dev) {
+static int disk_free(struct disk_state * disk) {
+    v3_file_close(disk->fd);
+    
+    V3_Free(disk);
     return 0;
 }
 
 static struct v3_device_ops dev_ops = {
-    .free = disk_free,
-    .reset = NULL,
-    .start = NULL,
-    .stop = NULL,
+    .free = (int (*)(void *))disk_free,
 };
 
 
 
 
-static int disk_init(struct guest_info * vm, v3_cfg_tree_t * cfg) {
+static int disk_init(struct v3_vm_info * vm, v3_cfg_tree_t * cfg) {
     struct disk_state * disk = NULL;
-    char * name = v3_cfg_val(cfg, "filename");
-    char * filename = v3_cfg_val(cfg, "file");
-
+    char * path = v3_cfg_val(cfg, "path");
+    char * dev_id = v3_cfg_val(cfg, "ID");
+    char * writable = v3_cfg_val(cfg, "writable");
     v3_cfg_tree_t * frontend_cfg = v3_cfg_subtree(cfg, "frontend");
+    int flags = FILE_OPEN_MODE_READ;
+
+    if ( (writable) && (writable[0] == '1') ) {
+       flags |= FILE_OPEN_MODE_WRITE;
+    }
+
+    if (path == NULL) {
+       PrintError("Missing path (%s) for %s\n", path, dev_id);
+       return -1;
+    }
 
     disk = (struct disk_state *)V3_Malloc(sizeof(struct disk_state));
+
+    if (disk == NULL) {
+       PrintError("Could not allocate disk\n");
+       return -1;
+    }
+
     memset(disk, 0, sizeof(struct disk_state));
 
+    struct vm_device * dev = v3_add_device(vm, dev_id, &dev_ops, disk);
 
-    if (!filename) {
-       PrintError("Missing filename (%s) for %s\n", filename, name);
+    if (dev == NULL) {
+       PrintError("Could not attach device %s\n", dev_id);
+       V3_Free(disk);
        return -1;
     }
-    
-    disk->fd = V3_FileOpen(filename, 0);
-    disk->capacity = V3_FileSize(disk->fd);
 
-    PrintDebug("Registering RAMDISK at %p (size=%d)\n", 
-              (void *)file->data, (uint32_t)file->size);
 
-    struct vm_device * dev = v3_allocate_device(name, &dev_ops, disk);
+    disk->fd = v3_file_open(vm, path, flags);
 
-    if (v3_attach_device(vm, dev) == -1) {
-       PrintError("Could not attach device %s\n", name);
+    if (disk->fd == NULL) {
+       PrintError("Could not open file disk:%s\n", path);
+       v3_remove_device(dev);
        return -1;
     }
 
+    disk->capacity = v3_file_size(disk->fd);
+
+    PrintDebug("Registering FILEDISK %s (path=%s, fd=%lu, size=%lu)\n",
+              dev_id, path, file->fd, file->capacity);
+
+
     if (v3_dev_connect_blk(vm, v3_cfg_val(frontend_cfg, "tag"), 
                           &blk_ops, frontend_cfg, disk) == -1) {
        PrintError("Could not connect %s to frontend %s\n", 
-                  name, v3_cfg_val(frontend_cfg, "tag"));
+                  dev_id, v3_cfg_val(frontend_cfg, "tag"));
+       v3_remove_device(dev);
        return -1;
     }