2 * Stream Implementation
7 #include <linux/errno.h>
8 #include <linux/percpu.h>
9 #include <linux/sched.h>
10 #include <linux/uaccess.h>
12 #include <linux/poll.h>
13 #include <linux/anon_inodes.h>
14 #include <linux/file.h>
17 #include <interfaces/vmm_stream.h>
18 #include "linux-exts.h"
19 #include "util-ringbuffer.h"
21 #include "iface-stream.h"
24 // This is going to need to be a lot bigger...
25 #define STREAM_BUF_SIZE 1024
30 static struct list_head global_streams;
32 struct stream_buffer {
33 char name[STREAM_NAME_LEN];
38 wait_queue_head_t intr_queue;
41 struct v3_guest * guest;
42 struct list_head stream_node;
46 // Currently just the list of open streams
47 struct vm_stream_state {
48 struct list_head open_streams;
52 static struct stream_buffer * find_stream_by_name(struct v3_guest * guest, const char * name) {
53 struct stream_buffer * stream = NULL;
54 struct list_head * stream_list = NULL;
55 struct vm_stream_state * vm_state = NULL;
58 stream_list = &global_streams;
60 vm_state = get_vm_ext_data(guest, "STREAM_INTERFACE");
62 if (vm_state == NULL) {
63 printk("ERROR: Could not locate vm stream state for extension STREAM_INTERFACE\n");
67 stream_list = &(vm_state->open_streams);
70 list_for_each_entry(stream, stream_list, stream_node) {
71 if (strncmp(stream->name, name, STREAM_NAME_LEN) == 0) {
81 static ssize_t stream_read(struct file * filp, char __user * buf, size_t size, loff_t * offset) {
82 struct stream_buffer * stream = filp->private_data;
84 wait_event_interruptible(stream->intr_queue, (ringbuf_data_len(stream->buf) != 0));
86 return ringbuf_read(stream->buf, buf, size);
91 static struct file_operations stream_fops = {
93 // .release = stream_close,
94 // .poll = stream_poll,
99 static void * palacios_stream_open(const char * name, void * private_data) {
100 struct v3_guest * guest = (struct v3_guest *)private_data;
101 struct stream_buffer * stream = NULL;
102 struct vm_stream_state * vm_state = NULL;
105 vm_state = get_vm_ext_data(guest, "STREAM_INTERFACE");
107 if (vm_state == NULL) {
108 printk("ERROR: Could not locate vm stream state for extension STREAM_INTERFACE\n");
113 if (find_stream_by_name(guest, name) != NULL) {
114 printk("Stream already exists\n");
118 stream = kmalloc(sizeof(struct stream_buffer), GFP_KERNEL);
120 stream->buf = create_ringbuf(STREAM_BUF_SIZE);
121 stream->guest = guest;
123 strncpy(stream->name, name, STREAM_NAME_LEN - 1);
125 init_waitqueue_head(&(stream->intr_queue));
126 spin_lock_init(&(stream->lock));
129 list_add(&(stream->stream_node), &(global_streams));
131 list_add(&(stream->stream_node), &(vm_state->open_streams));
138 static int palacios_stream_write(void * stream_ptr, char * buf, int len) {
139 struct stream_buffer * stream = (struct stream_buffer *)stream_ptr;
142 ret = ringbuf_write(stream->buf, buf, len);
145 wake_up_interruptible(&(stream->intr_queue));
152 static void palacios_stream_close(void * stream_ptr) {
153 struct stream_buffer * stream = (struct stream_buffer *)stream_ptr;
155 free_ringbuf(stream->buf);
156 list_del(&(stream->stream_node));
161 static struct v3_stream_hooks palacios_stream_hooks = {
162 .open = palacios_stream_open,
163 .write = palacios_stream_write,
164 .close = palacios_stream_close,
168 static int stream_init( void ) {
169 INIT_LIST_HEAD(&(global_streams));
170 V3_Init_Stream(&palacios_stream_hooks);
176 static int stream_deinit( void ) {
177 if (!list_empty(&(global_streams))) {
178 printk("Error removing module with open streams\n");
179 printk("TODO: free old streams... \n");
189 static int stream_connect(struct v3_guest * guest, unsigned int cmd, unsigned long arg, void * priv_data) {
190 void __user * argp = (void __user *)arg;
191 struct stream_buffer * stream = NULL;
193 char name[STREAM_NAME_LEN];
194 unsigned long flags = 0;
198 if (copy_from_user(name, argp, STREAM_NAME_LEN)) {
199 printk("%s(%d): copy from user error...\n", __FILE__, __LINE__);
203 stream = find_stream_by_name(guest, name);
205 if (stream == NULL) {
206 printk("Could not find stream (%s)\n", name);
210 spin_lock_irqsave(&(stream->lock), flags);
211 if (stream->connected == 0) {
212 stream->connected = 1;
215 spin_unlock_irqrestore(&(stream->lock), flags);
219 printk("Stream (%s) already connected\n", name);
224 stream_fd = anon_inode_getfd("v3-stream", &stream_fops, stream, 0);
227 printk("Error creating stream inode for (%s)\n", name);
231 printk("Stream (%s) connected\n", name);
237 static int guest_stream_init(struct v3_guest * guest, void ** vm_data) {
238 struct vm_stream_state * state = kmalloc(sizeof(struct vm_stream_state), GFP_KERNEL);
240 INIT_LIST_HEAD(&(state->open_streams));
244 add_guest_ctrl(guest, V3_VM_STREAM_CONNECT, stream_connect, state);
250 static int guest_stream_deinit(struct v3_guest * guest, void * vm_data) {
251 struct vm_stream_state * state = vm_data;
252 if (!list_empty(&(state->open_streams))) {
253 printk("Error shutting down VM with open streams\n");
261 static struct linux_ext stream_ext = {
262 .name = "STREAM_INTERFACE",
264 .deinit = stream_deinit,
265 .guest_init = guest_stream_init,
266 .guest_deinit = guest_stream_deinit
270 register_extension(&stream_ext);