--- /dev/null
+/* Palacios file interface
+ * (c) Jack Lange, 2010
+ */
+
+
+#include <linux/fs.h>
+#include <linux/file.h>
+#include <linux/spinlock.h>
+#include <linux/uaccess.h>
+#include <linux/module.h>
+
+#include "palacios.h"
+#include "linux-exts.h"
+
+#include <interfaces/vmm_file.h>
+
+static struct list_head global_files;
+
+
+struct palacios_file {
+ struct file * filp;
+
+ char * path;
+ int mode;
+
+ spinlock_t lock;
+
+ struct v3_guest * guest;
+
+
+ struct list_head file_node;
+};
+
+
+// Currently this just holds the list of open files
+struct vm_file_state {
+ struct list_head open_files;
+};
+
+
+
+static void * palacios_file_open(const char * path, int mode, void * private_data) {
+ struct v3_guest * guest = (struct v3_guest *)private_data;
+ struct palacios_file * pfile = NULL;
+ struct vm_file_state * vm_state = NULL;
+
+ if (guest != NULL) {
+ vm_state = get_vm_ext_data(guest, "FILE_INTERFACE");
+
+ if (vm_state == NULL) {
+ printk("ERROR: Could not locate vm file state for extension FILE_INTERFACE\n");
+ return NULL;
+ }
+ }
+
+ pfile = kmalloc(sizeof(struct palacios_file), GFP_KERNEL);
+ memset(pfile, 0, sizeof(struct palacios_file));
+
+ if ((mode & FILE_OPEN_MODE_READ) && (mode & FILE_OPEN_MODE_WRITE)) {
+ pfile->mode = O_RDWR;
+ } else if (mode & FILE_OPEN_MODE_READ) {
+ pfile->mode = O_RDONLY;
+ } else if (mode & FILE_OPEN_MODE_WRITE) {
+ pfile->mode = O_WRONLY;
+ }
+
+ pfile->filp = filp_open(path, pfile->mode, 0);
+
+ if (pfile->filp == NULL) {
+ printk("Cannot open file: %s\n", path);
+ return NULL;
+ }
+
+ pfile->path = kmalloc(strlen(path) + 1, GFP_KERNEL);
+ strncpy(pfile->path, path, strlen(path));
+ pfile->guest = guest;
+
+ spin_lock_init(&(pfile->lock));
+
+ if (guest == NULL) {
+ list_add(&(pfile->file_node), &(global_files));
+ } else {
+ list_add(&(pfile->file_node), &(vm_state->open_files));
+ }
+
+
+ return pfile;
+}
+
+static int palacios_file_close(void * file_ptr) {
+ struct palacios_file * pfile = (struct palacios_file *)file_ptr;
+
+ filp_close(pfile->filp, NULL);
+
+ list_del(&(pfile->file_node));
+
+ kfree(pfile->path);
+ kfree(pfile);
+
+ return 0;
+}
+
+static long long palacios_file_size(void * file_ptr) {
+ struct palacios_file * pfile = (struct palacios_file *)file_ptr;
+ struct file * filp = pfile->filp;
+ struct kstat s;
+ int ret;
+
+ ret = vfs_getattr(filp->f_path.mnt, filp->f_path.dentry, &s);
+
+ if (ret != 0) {
+ printk("Failed to fstat file\n");
+ return -1;
+ }
+
+ return s.size;
+}
+
+static long long palacios_file_read(void * file_ptr, void * buffer, long long length, long long offset){
+ struct palacios_file * pfile = (struct palacios_file *)file_ptr;
+ struct file * filp = pfile->filp;
+ ssize_t ret;
+ mm_segment_t old_fs;
+
+ old_fs = get_fs();
+ set_fs(get_ds());
+
+ ret = vfs_read(filp, buffer, length, &offset);
+
+ set_fs(old_fs);
+
+ if (ret <= 0) {
+ printk("sys_read of %p for %lld bytes failed\n", filp, length);
+ }
+
+ return ret;
+}
+
+
+static long long palacios_file_write(void * file_ptr, void * buffer, long long length, long long offset) {
+ struct palacios_file * pfile = (struct palacios_file *)file_ptr;
+ struct file * filp = pfile->filp;
+ mm_segment_t old_fs;
+ ssize_t ret;
+
+ old_fs = get_fs();
+ set_fs(get_ds());
+
+ ret = vfs_write(filp, buffer, length, &offset);
+
+ set_fs(old_fs);
+
+
+ if (ret <= 0) {
+ printk("sys_write failed\n");
+ }
+
+ return ret;
+}
+
+
+static struct v3_file_hooks palacios_file_hooks = {
+ .open = palacios_file_open,
+ .close = palacios_file_close,
+ .read = palacios_file_read,
+ .write = palacios_file_write,
+ .size = palacios_file_size,
+};
+
+
+
+static int file_init( void ) {
+ INIT_LIST_HEAD(&(global_files));
+
+ V3_Init_File(&palacios_file_hooks);
+
+ return 0;
+}
+
+
+static int file_deinit( void ) {
+ if (!list_empty(&(global_files))) {
+ printk("Error removing module with open files\n");
+ }
+
+ return 0;
+}
+
+static int guest_file_init(struct v3_guest * guest, void ** vm_data) {
+ struct vm_file_state * state = kmalloc(sizeof(struct vm_file_state), GFP_KERNEL);
+
+ INIT_LIST_HEAD(&(state->open_files));
+
+ *vm_data = state;
+
+ return 0;
+}
+
+
+static int guest_file_deinit(struct v3_guest * guest, void * vm_data) {
+
+ return 0;
+}
+
+
+static struct linux_ext file_ext = {
+ .name = "FILE_INTERFACE",
+ .init = file_init,
+ .deinit = file_deinit,
+ .guest_init = guest_file_init,
+ .guest_deinit = guest_file_deinit
+};
+
+
+register_extension(&file_ext);
