Added blktap support. Includes kernel driver (enabled as CONFIG_XEN_BLKDEV_TAP=y) and userspace tools. The userspace deamon (blktapctrl) is enabled by default when xend is activated. For further information on using and configuring blktap see tools/blktap/README.

1 files changed, 297 insertions, 0 deletions

diff --git a/patches/linux-2.6.16.13/blktap-aio-16_03_06.patch b/patches/linux-2.6.16.13/blktap-aio-16_03_06.patch
new file mode 100644
index 0000000000..5f4fd6f7a9
--- /dev/null
+++ b/patches/linux-2.6.16.13/blktap-aio-16_03_06.patch
@@ -0,0 +1,297 @@
+diff -pruN ../pristine-linux-2.6.16-rc5/fs/aio.c ./fs/aio.c
+--- ../pristine-linux-2.6.16-rc5/fs/aio.c	2006-03-14 14:10:10.827401387 +0000
++++ ./fs/aio.c	2006-03-16 09:57:53.898316582 +0000
+@@ -34,6 +34,11 @@
+ #include <asm/uaccess.h>
+ #include <asm/mmu_context.h>
+ 
++#ifdef CONFIG_EPOLL
++#include <linux/poll.h>
++#include <linux/eventpoll.h>
++#endif
++
+ #if DEBUG > 1
+ #define dprintk		printk
+ #else
+@@ -1016,6 +1021,10 @@ put_rq:
+ 	if (waitqueue_active(&ctx->wait))
+ 		wake_up(&ctx->wait);
+ 
++#ifdef CONFIG_EPOLL
++	if (ctx->file && waitqueue_active(&ctx->poll_wait))
++		wake_up(&ctx->poll_wait);
++#endif
+ 	if (ret)
+ 		put_ioctx(ctx);
+ 
+@@ -1025,6 +1034,8 @@ put_rq:
+ /* aio_read_evt
+  *	Pull an event off of the ioctx's event ring.  Returns the number of 
+  *	events fetched (0 or 1 ;-)
++ *	If ent parameter is 0, just returns the number of events that would
++ *	be fetched.
+  *	FIXME: make this use cmpxchg.
+  *	TODO: make the ringbuffer user mmap()able (requires FIXME).
+  */
+@@ -1047,13 +1058,18 @@ static int aio_read_evt(struct kioctx *i
+ 
+ 	head = ring->head % info->nr;
+ 	if (head != ring->tail) {
+-		struct io_event *evp = aio_ring_event(info, head, KM_USER1);
+-		*ent = *evp;
+-		head = (head + 1) % info->nr;
+-		smp_mb(); /* finish reading the event before updatng the head */
+-		ring->head = head;
+-		ret = 1;
+-		put_aio_ring_event(evp, KM_USER1);
++		if (ent) { /* event requested */
++			struct io_event *evp =
++				aio_ring_event(info, head, KM_USER1);
++			*ent = *evp;
++			head = (head + 1) % info->nr;
++			/* finish reading the event before updatng the head */
++			smp_mb();
++			ring->head = head;
++			ret = 1;
++			put_aio_ring_event(evp, KM_USER1);
++		} else /* only need to know availability */
++			ret = 1;
+ 	}
+ 	spin_unlock(&info->ring_lock);
+ 
+@@ -1236,9 +1252,78 @@ static void io_destroy(struct kioctx *io
+ 
+ 	aio_cancel_all(ioctx);
+ 	wait_for_all_aios(ioctx);
++#ifdef CONFIG_EPOLL
++	/* forget the poll file, but it's up to the user to close it */
++	if (ioctx->file) {
++		ioctx->file->private_data = 0;
++		ioctx->file = 0;
++	}
++#endif
+ 	put_ioctx(ioctx);	/* once for the lookup */
+ }
+ 
++#ifdef CONFIG_EPOLL
++
++static int aio_queue_fd_close(struct inode *inode, struct file *file)
++{
++	struct kioctx *ioctx = file->private_data;
++	if (ioctx) {
++		file->private_data = 0;
++		spin_lock_irq(&ioctx->ctx_lock);
++		ioctx->file = 0;
++		spin_unlock_irq(&ioctx->ctx_lock);
++	}
++	return 0;
++}
++
++static unsigned int aio_queue_fd_poll(struct file *file, poll_table *wait)
++{	unsigned int pollflags = 0;
++	struct kioctx *ioctx = file->private_data;
++
++	if (ioctx) {
++
++		spin_lock_irq(&ioctx->ctx_lock);
++		/* Insert inside our poll wait queue */
++		poll_wait(file, &ioctx->poll_wait, wait);
++
++		/* Check our condition */
++		if (aio_read_evt(ioctx, 0))
++			pollflags = POLLIN | POLLRDNORM;
++		spin_unlock_irq(&ioctx->ctx_lock);
++	}
++
++	return pollflags;
++}
++
++static struct file_operations aioq_fops = {
++	.release	= aio_queue_fd_close,
++	.poll		= aio_queue_fd_poll
++};
++
++/* make_aio_fd:
++ *  Create a file descriptor that can be used to poll the event queue.
++ *  Based and piggybacked on the excellent epoll code.
++ */
++
++static int make_aio_fd(struct kioctx *ioctx)
++{
++	int error, fd;
++	struct inode *inode;
++	struct file *file;
++
++	error = ep_getfd(&fd, &inode, &file, NULL, &aioq_fops);
++	if (error)
++		return error;
++
++	/* associate the file with the IO context */
++	file->private_data = ioctx;
++	ioctx->file = file;
++	init_waitqueue_head(&ioctx->poll_wait);
++	return fd;
++}
++#endif
++
++
+ /* sys_io_setup:
+  *	Create an aio_context capable of receiving at least nr_events.
+  *	ctxp must not point to an aio_context that already exists, and
+@@ -1251,18 +1336,30 @@ static void io_destroy(struct kioctx *io
+  *	resources are available.  May fail with -EFAULT if an invalid
+  *	pointer is passed for ctxp.  Will fail with -ENOSYS if not
+  *	implemented.
++ *
++ *	To request a selectable fd, the user context has to be initialized
++ *	to 1, instead of 0, and the return value is the fd.
++ *	This keeps the system call compatible, since a non-zero value
++ *	was not allowed so far.
+  */
+ asmlinkage long sys_io_setup(unsigned nr_events, aio_context_t __user *ctxp)
+ {
+ 	struct kioctx *ioctx = NULL;
+ 	unsigned long ctx;
+ 	long ret;
++	int make_fd = 0;
+ 
+ 	ret = get_user(ctx, ctxp);
+ 	if (unlikely(ret))
+ 		goto out;
+ 
+ 	ret = -EINVAL;
++#ifdef CONFIG_EPOLL
++	if (ctx == 1) {
++		make_fd = 1;
++		ctx = 0;
++	}
++#endif
+ 	if (unlikely(ctx || nr_events == 0)) {
+ 		pr_debug("EINVAL: io_setup: ctx %lu nr_events %u\n",
+ 		         ctx, nr_events);
+@@ -1273,8 +1370,12 @@ asmlinkage long sys_io_setup(unsigned nr
+ 	ret = PTR_ERR(ioctx);
+ 	if (!IS_ERR(ioctx)) {
+ 		ret = put_user(ioctx->user_id, ctxp);
+-		if (!ret)
+-			return 0;
++#ifdef CONFIG_EPOLL
++		if (make_fd && ret >= 0)
++			ret = make_aio_fd(ioctx);
++#endif
++		if (ret >= 0)
++			return ret;
+ 
+ 		get_ioctx(ioctx); /* io_destroy() expects us to hold a ref */
+ 		io_destroy(ioctx);
+
+diff -pruN ../pristine-linux-2.6.16-rc5/fs/eventpoll.c ./fs/eventpoll.c
+--- ../pristine-linux-2.6.16-rc5/fs/eventpoll.c	2006-01-03 03:21:10.000000000 +0000
++++ ./fs/eventpoll.c	2006-03-16 10:04:35.469956167 +0000
+@@ -235,8 +235,6 @@ struct ep_pqueue {
+ 
+ static void ep_poll_safewake_init(struct poll_safewake *psw);
+ static void ep_poll_safewake(struct poll_safewake *psw, wait_queue_head_t *wq);
+-static int ep_getfd(int *efd, struct inode **einode, struct file **efile,
+-		    struct eventpoll *ep);
+ static int ep_alloc(struct eventpoll **pep);
+ static void ep_free(struct eventpoll *ep);
+ static struct epitem *ep_find(struct eventpoll *ep, struct file *file, int fd);
+@@ -266,7 +264,7 @@ static int ep_events_transfer(struct eve
+ static int ep_poll(struct eventpoll *ep, struct epoll_event __user *events,
+ 		   int maxevents, long timeout);
+ static int eventpollfs_delete_dentry(struct dentry *dentry);
+-static struct inode *ep_eventpoll_inode(void);
++static struct inode *ep_eventpoll_inode(struct file_operations *fops);
+ static struct super_block *eventpollfs_get_sb(struct file_system_type *fs_type,
+ 					      int flags, const char *dev_name,
+ 					      void *data);
+@@ -525,7 +523,7 @@ asmlinkage long sys_epoll_create(int siz
+ 	 * Creates all the items needed to setup an eventpoll file. That is,
+ 	 * a file structure, and inode and a free file descriptor.
+ 	 */
+-	error = ep_getfd(&fd, &inode, &file, ep);
++	error = ep_getfd(&fd, &inode, &file, ep, &eventpoll_fops);
+ 	if (error)
+ 		goto eexit_2;
+ 
+@@ -710,8 +708,8 @@ eexit_1:
+ /*
+  * Creates the file descriptor to be used by the epoll interface.
+  */
+-static int ep_getfd(int *efd, struct inode **einode, struct file **efile,
+-		    struct eventpoll *ep)
++int ep_getfd(int *efd, struct inode **einode, struct file **efile,
++		    struct eventpoll *ep, struct file_operations *fops)
+ {
+ 	struct qstr this;
+ 	char name[32];
+@@ -727,7 +725,7 @@ static int ep_getfd(int *efd, struct ino
+ 		goto eexit_1;
+ 
+ 	/* Allocates an inode from the eventpoll file system */
+-	inode = ep_eventpoll_inode();
++	inode = ep_eventpoll_inode(fops);
+ 	error = PTR_ERR(inode);
+ 	if (IS_ERR(inode))
+ 		goto eexit_2;
+@@ -758,7 +756,7 @@ static int ep_getfd(int *efd, struct ino
+ 
+ 	file->f_pos = 0;
+ 	file->f_flags = O_RDONLY;
+-	file->f_op = &eventpoll_fops;
++	file->f_op = fops;
+ 	file->f_mode = FMODE_READ;
+ 	file->f_version = 0;
+ 	file->private_data = ep;
+@@ -1574,7 +1572,7 @@ static int eventpollfs_delete_dentry(str
+ }
+ 
+ 
+-static struct inode *ep_eventpoll_inode(void)
++static struct inode *ep_eventpoll_inode(struct file_operations *fops)
+ {
+ 	int error = -ENOMEM;
+ 	struct inode *inode = new_inode(eventpoll_mnt->mnt_sb);
+@@ -1582,7 +1580,7 @@ static struct inode *ep_eventpoll_inode(
+ 	if (!inode)
+ 		goto eexit_1;
+ 
+-	inode->i_fop = &eventpoll_fops;
++	inode->i_fop = fops;
+ 
+ 	/*
+ 	 * Mark the inode dirty from the very beginning,
+
+diff -pruN ../pristine-linux-2.6.16-rc5/include/linux/aio.h ./include/linux/aio.h
+--- ../pristine-linux-2.6.16-rc5/include/linux/aio.h	2006-03-14 14:10:21.597916731 +0000
++++ ./include/linux/aio.h	2006-03-16 10:05:39.848833028 +0000
+@@ -191,6 +191,11 @@ struct kioctx {
+ 	struct aio_ring_info	ring_info;
+ 
+ 	struct work_struct	wq;
++#ifdef CONFIG_EPOLL
++	// poll integration
++	wait_queue_head_t       poll_wait;
++	struct file		*file;
++#endif
+ };
+ 
+ /* prototypes */
+
+diff -pruN ../pristine-linux-2.6.16-rc5/include/linux/eventpoll.h ./include/linux/eventpoll.h
+--- ../pristine-linux-2.6.16-rc5/include/linux/eventpoll.h	2006-01-03 03:21:10.000000000 +0000
++++ ./include/linux/eventpoll.h	2006-03-16 10:08:51.577809317 +0000
+@@ -86,6 +86,12 @@ static inline void eventpoll_release(str
+ }
+ 
+ 
++/*
++ * called by aio code to create fd that can poll the  aio event queueQ
++ */
++struct eventpoll;
++int ep_getfd(int *efd, struct inode **einode, struct file **efile,
++             struct eventpoll *ep, struct file_operations *fops);
+ #else
+ 
+ static inline void eventpoll_init_file(struct file *file) {}