Re: [Xen-changelog] [xen-unstable] [LINUX][XENBUS] replace xenbus_transaction_t with an opaque transaction ID.

Re: [Xen-changelog] [xen-unstable] [LINUX][XENBUS] replace xenbus_transaction_t with an opaque transaction ID.

[Anthony Liguori]

Xen patchbot-unstable wrote:
> # HG changeset patch
> # User kaf24@firebug.cl.cam.ac.uk
> # Node ID 49f65e2b0f1c5b96326c764808e819af85e883d7
> # Parent  7cf4cbe7a3be88e7bde56c4093428749bf5320d7
> [LINUX][XENBUS] replace xenbus_transaction_t with an opaque transaction ID.
> xenbus_transaction_t -> struct xenbus_transaction, which just contains
> a single u32.  Also renamed XBT_NULL to XBT_NIL to emphasize that it
> isn't a NULL pointer, but a NIL transaction ID.  Compile and boot tested.
>
> Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
> [chrisw: updated for xen-unstable from patchqueue]
> Signed-off-by: Chris Wright <chrisw@sous-sol.org>
>   

Can't we just go back to the original semantics and s/XBT_NIL/NULL/g.  
The whole reason XBT_NULL was introduced was that it switched to an 
integer and NULL used to represent no transaction.

Regards,

Anthony Liguori

> ---
>  linux-2.6-xen-sparse/drivers/char/tpm/tpm_xen.c         |    4 -
>  linux-2.6-xen-sparse/drivers/xen/balloon/balloon.c      |    2 
>  linux-2.6-xen-sparse/drivers/xen/blkback/xenbus.c       |    8 +--
>  linux-2.6-xen-sparse/drivers/xen/blkfront/blkfront.c    |    6 +-
>  linux-2.6-xen-sparse/drivers/xen/core/cpu_hotplug.c     |    2 
>  linux-2.6-xen-sparse/drivers/xen/core/reboot.c          |    4 -
>  linux-2.6-xen-sparse/drivers/xen/netback/xenbus.c       |   12 ++---
>  linux-2.6-xen-sparse/drivers/xen/netfront/netfront.c    |    8 +--
>  linux-2.6-xen-sparse/drivers/xen/pciback/xenbus.c       |   14 +++---
>  linux-2.6-xen-sparse/drivers/xen/pcifront/xenbus.c      |    6 +-
>  linux-2.6-xen-sparse/drivers/xen/tpmback/xenbus.c       |    6 +-
>  linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_client.c |    8 +--
>  linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_dev.c    |    6 +-
>  linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_probe.c  |   16 +++----
>  linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_xs.c     |   36 ++++++++--------
>  linux-2.6-xen-sparse/include/xen/xenbus.h               |   34 ++++++++-------
>  16 files changed, 88 insertions(+), 84 deletions(-)
>
> diff -r 7cf4cbe7a3be -r 49f65e2b0f1c linux-2.6-xen-sparse/drivers/char/tpm/tpm_xen.c
> --- a/linux-2.6-xen-sparse/drivers/char/tpm/tpm_xen.c	Fri Jun 09 14:23:50 2006 +0100
> +++ b/linux-2.6-xen-sparse/drivers/char/tpm/tpm_xen.c	Fri Jun 09 14:25:46 2006 +0100
> @@ -274,7 +274,7 @@ static int talk_to_backend(struct xenbus
>  {
>  	const char *message = NULL;
>  	int err;
> -	xenbus_transaction_t xbt;
> +	struct xenbus_transaction xbt;
>  
>  	err = setup_tpmring(dev, tp);
>  	if (err) {
> @@ -369,7 +369,7 @@ static int tpmfront_probe(struct xenbus_
>  	if (!tp)
>  		return -ENOMEM;
>  
> -	err = xenbus_scanf(XBT_NULL, dev->nodename,
> +	err = xenbus_scanf(XBT_NIL, dev->nodename,
>  	                   "handle", "%i", &handle);
>  	if (XENBUS_EXIST_ERR(err))
>  		return err;
> diff -r 7cf4cbe7a3be -r 49f65e2b0f1c linux-2.6-xen-sparse/drivers/xen/balloon/balloon.c
> --- a/linux-2.6-xen-sparse/drivers/xen/balloon/balloon.c	Fri Jun 09 14:23:50 2006 +0100
> +++ b/linux-2.6-xen-sparse/drivers/xen/balloon/balloon.c	Fri Jun 09 14:25:46 2006 +0100
> @@ -378,7 +378,7 @@ static void watch_target(struct xenbus_w
>  	unsigned long long new_target;
>  	int err;
>  
> -	err = xenbus_scanf(XBT_NULL, "memory", "target", "%llu", &new_target);
> +	err = xenbus_scanf(XBT_NIL, "memory", "target", "%llu", &new_target);
>  	if (err != 1) {
>  		/* This is ok (for domain0 at least) - so just return */
>  		return;
> diff -r 7cf4cbe7a3be -r 49f65e2b0f1c linux-2.6-xen-sparse/drivers/xen/blkback/xenbus.c
> --- a/linux-2.6-xen-sparse/drivers/xen/blkback/xenbus.c	Fri Jun 09 14:23:50 2006 +0100
> +++ b/linux-2.6-xen-sparse/drivers/xen/blkback/xenbus.c	Fri Jun 09 14:25:46 2006 +0100
> @@ -186,7 +186,7 @@ static void backend_changed(struct xenbu
>  
>  	DPRINTK("");
>  
> -	err = xenbus_scanf(XBT_NULL, dev->nodename, "physical-device", "%x:%x",
> +	err = xenbus_scanf(XBT_NIL, dev->nodename, "physical-device", "%x:%x",
>  			   &major, &minor);
>  	if (XENBUS_EXIST_ERR(err)) {
>  		/* Since this watch will fire once immediately after it is
> @@ -208,7 +208,7 @@ static void backend_changed(struct xenbu
>  		return;
>  	}
>  
> -	be->mode = xenbus_read(XBT_NULL, dev->nodename, "mode", NULL);
> +	be->mode = xenbus_read(XBT_NIL, dev->nodename, "mode", NULL);
>  	if (IS_ERR(be->mode)) {
>  		err = PTR_ERR(be->mode);
>  		be->mode = NULL;
> @@ -299,7 +299,7 @@ static void frontend_changed(struct xenb
>   */
>  static void connect(struct backend_info *be)
>  {
> -	xenbus_transaction_t xbt;
> +	struct xenbus_transaction xbt;
>  	int err;
>  	struct xenbus_device *dev = be->dev;
>  
> @@ -364,7 +364,7 @@ static int connect_ring(struct backend_i
>  
>  	DPRINTK("%s", dev->otherend);
>  
> -	err = xenbus_gather(XBT_NULL, dev->otherend, "ring-ref", "%lu", &ring_ref,
> +	err = xenbus_gather(XBT_NIL, dev->otherend, "ring-ref", "%lu", &ring_ref,
>  			    "event-channel", "%u", &evtchn, NULL);
>  	if (err) {
>  		xenbus_dev_fatal(dev, err,
> diff -r 7cf4cbe7a3be -r 49f65e2b0f1c linux-2.6-xen-sparse/drivers/xen/blkfront/blkfront.c
> --- a/linux-2.6-xen-sparse/drivers/xen/blkfront/blkfront.c	Fri Jun 09 14:23:50 2006 +0100
> +++ b/linux-2.6-xen-sparse/drivers/xen/blkfront/blkfront.c	Fri Jun 09 14:25:46 2006 +0100
> @@ -83,7 +83,7 @@ static int blkfront_probe(struct xenbus_
>  	struct blkfront_info *info;
>  
>  	/* FIXME: Use dynamic device id if this is not set. */
> -	err = xenbus_scanf(XBT_NULL, dev->nodename,
> +	err = xenbus_scanf(XBT_NIL, dev->nodename,
>  			   "virtual-device", "%i", &vdevice);
>  	if (err != 1) {
>  		xenbus_dev_fatal(dev, err, "reading virtual-device");
> @@ -148,7 +148,7 @@ static int talk_to_backend(struct xenbus
>  			   struct blkfront_info *info)
>  {
>  	const char *message = NULL;
> -	xenbus_transaction_t xbt;
> +	struct xenbus_transaction xbt;
>  	int err;
>  
>  	/* Create shared ring, alloc event channel. */
> @@ -303,7 +303,7 @@ static void connect(struct blkfront_info
>  
>  	DPRINTK("blkfront.c:connect:%s.\n", info->xbdev->otherend);
>  
> -	err = xenbus_gather(XBT_NULL, info->xbdev->otherend,
> +	err = xenbus_gather(XBT_NIL, info->xbdev->otherend,
>  			    "sectors", "%lu", &sectors,
>  			    "info", "%u", &binfo,
>  			    "sector-size", "%lu", &sector_size,
> diff -r 7cf4cbe7a3be -r 49f65e2b0f1c linux-2.6-xen-sparse/drivers/xen/core/cpu_hotplug.c
> --- a/linux-2.6-xen-sparse/drivers/xen/core/cpu_hotplug.c	Fri Jun 09 14:23:50 2006 +0100
> +++ b/linux-2.6-xen-sparse/drivers/xen/core/cpu_hotplug.c	Fri Jun 09 14:25:46 2006 +0100
> @@ -34,7 +34,7 @@ static void vcpu_hotplug(unsigned int cp
>  		return;
>  
>  	sprintf(dir, "cpu/%d", cpu);
> -	err = xenbus_scanf(XBT_NULL, dir, "availability", "%s", state);
> +	err = xenbus_scanf(XBT_NIL, dir, "availability", "%s", state);
>  	if (err != 1) {
>  		printk(KERN_ERR "XENBUS: Unable to read cpu state\n");
>  		return;
> diff -r 7cf4cbe7a3be -r 49f65e2b0f1c linux-2.6-xen-sparse/drivers/xen/core/reboot.c
> --- a/linux-2.6-xen-sparse/drivers/xen/core/reboot.c	Fri Jun 09 14:23:50 2006 +0100
> +++ b/linux-2.6-xen-sparse/drivers/xen/core/reboot.c	Fri Jun 09 14:25:46 2006 +0100
> @@ -250,7 +250,7 @@ static void shutdown_handler(struct xenb
>  			     const char **vec, unsigned int len)
>  {
>  	char *str;
> -	xenbus_transaction_t xbt;
> +	struct xenbus_transaction xbt;
>  	int err;
>  
>  	if (shutting_down != SHUTDOWN_INVALID)
> @@ -298,7 +298,7 @@ static void sysrq_handler(struct xenbus_
>  			  unsigned int len)
>  {
>  	char sysrq_key = '\0';
> -	xenbus_transaction_t xbt;
> +	struct xenbus_transaction xbt;
>  	int err;
>  
>   again:
> diff -r 7cf4cbe7a3be -r 49f65e2b0f1c linux-2.6-xen-sparse/drivers/xen/netback/xenbus.c
> --- a/linux-2.6-xen-sparse/drivers/xen/netback/xenbus.c	Fri Jun 09 14:23:50 2006 +0100
> +++ b/linux-2.6-xen-sparse/drivers/xen/netback/xenbus.c	Fri Jun 09 14:25:46 2006 +0100
> @@ -70,7 +70,7 @@ static int netback_probe(struct xenbus_d
>  			 const struct xenbus_device_id *id)
>  {
>  	const char *message;
> -	xenbus_transaction_t xbt;
> +	struct xenbus_transaction xbt;
>  	int err;
>  	struct backend_info *be = kzalloc(sizeof(struct backend_info),
>  					  GFP_KERNEL);
> @@ -141,7 +141,7 @@ static int netback_uevent(struct xenbus_
>  
>  	DPRINTK("netback_uevent");
>  
> -	val = xenbus_read(XBT_NULL, xdev->nodename, "script", NULL);
> +	val = xenbus_read(XBT_NIL, xdev->nodename, "script", NULL);
>  	if (IS_ERR(val)) {
>  		int err = PTR_ERR(val);
>  		xenbus_dev_fatal(xdev, err, "reading script");
> @@ -177,7 +177,7 @@ static void backend_changed(struct xenbu
>  
>  	DPRINTK("");
>  
> -	err = xenbus_scanf(XBT_NULL, dev->nodename, "handle", "%li", &handle);
> +	err = xenbus_scanf(XBT_NIL, dev->nodename, "handle", "%li", &handle);
>  	if (XENBUS_EXIST_ERR(err)) {
>  		/* Since this watch will fire once immediately after it is
>  		   registered, we expect this.  Ignore it, and wait for the
> @@ -268,7 +268,7 @@ static void xen_net_read_rate(struct xen
>  	*bytes = ~0UL;
>  	*usec = 0;
>  
> -	ratestr = xenbus_read(XBT_NULL, dev->nodename, "rate", NULL);
> +	ratestr = xenbus_read(XBT_NIL, dev->nodename, "rate", NULL);
>  	if (IS_ERR(ratestr))
>  		return;
>  
> @@ -298,7 +298,7 @@ static int xen_net_read_mac(struct xenbu
>  	char *s, *e, *macstr;
>  	int i;
>  
> -	macstr = s = xenbus_read(XBT_NULL, dev->nodename, "mac", NULL);
> +	macstr = s = xenbus_read(XBT_NIL, dev->nodename, "mac", NULL);
>  	if (IS_ERR(macstr))
>  		return PTR_ERR(macstr);
>  
> @@ -347,7 +347,7 @@ static int connect_rings(struct backend_
>  
>  	DPRINTK("");
>  
> -	err = xenbus_gather(XBT_NULL, dev->otherend,
> +	err = xenbus_gather(XBT_NIL, dev->otherend,
>  			    "tx-ring-ref", "%lu", &tx_ring_ref,
>  			    "rx-ring-ref", "%lu", &rx_ring_ref,
>  			    "event-channel", "%u", &evtchn, NULL);
> diff -r 7cf4cbe7a3be -r 49f65e2b0f1c linux-2.6-xen-sparse/drivers/xen/netfront/netfront.c
> --- a/linux-2.6-xen-sparse/drivers/xen/netfront/netfront.c	Fri Jun 09 14:23:50 2006 +0100
> +++ b/linux-2.6-xen-sparse/drivers/xen/netfront/netfront.c	Fri Jun 09 14:25:46 2006 +0100
> @@ -193,7 +193,7 @@ static int __devinit netfront_probe(stru
>  	struct netfront_info *info;
>  	unsigned int handle;
>  
> -	err = xenbus_scanf(XBT_NULL, dev->nodename, "handle", "%u", &handle);
> +	err = xenbus_scanf(XBT_NIL, dev->nodename, "handle", "%u", &handle);
>  	if (err != 1) {
>  		xenbus_dev_fatal(dev, err, "reading handle");
>  		return err;
> @@ -243,7 +243,7 @@ static int xen_net_read_mac(struct xenbu
>  	char *s, *e, *macstr;
>  	int i;
>  
> -	macstr = s = xenbus_read(XBT_NULL, dev->nodename, "mac", NULL);
> +	macstr = s = xenbus_read(XBT_NIL, dev->nodename, "mac", NULL);
>  	if (IS_ERR(macstr))
>  		return PTR_ERR(macstr);
>  
> @@ -265,7 +265,7 @@ static int talk_to_backend(struct xenbus
>  			   struct netfront_info *info)
>  {
>  	const char *message;
> -	xenbus_transaction_t xbt;
> +	struct xenbus_transaction xbt;
>  	int err;
>  
>  	err = xen_net_read_mac(dev, info->mac);
> @@ -1057,7 +1057,7 @@ static int xennet_set_sg(struct net_devi
>  		struct netfront_info *np = netdev_priv(dev);
>  		int val;
>  
> -		if (xenbus_scanf(XBT_NULL, np->xbdev->otherend, "feature-sg",
> +		if (xenbus_scanf(XBT_NIL, np->xbdev->otherend, "feature-sg",
>  				 "%d", &val) < 0)
>  			val = 0;
>  		if (!val)
> diff -r 7cf4cbe7a3be -r 49f65e2b0f1c linux-2.6-xen-sparse/drivers/xen/pciback/xenbus.c
> --- a/linux-2.6-xen-sparse/drivers/xen/pciback/xenbus.c	Fri Jun 09 14:23:50 2006 +0100
> +++ b/linux-2.6-xen-sparse/drivers/xen/pciback/xenbus.c	Fri Jun 09 14:25:46 2006 +0100
> @@ -125,7 +125,7 @@ static int pciback_attach(struct pciback
>  
>  	dev_dbg(&pdev->xdev->dev, "Reading frontend config\n");
>  
> -	err = xenbus_gather(XBT_NULL, pdev->xdev->otherend,
> +	err = xenbus_gather(XBT_NIL, pdev->xdev->otherend,
>  			    "pci-op-ref", "%u", &gnt_ref,
>  			    "event-channel", "%u", &remote_evtchn,
>  			    "magic", NULL, &magic, NULL);
> @@ -200,7 +200,7 @@ static int pciback_publish_pci_root(stru
>  
>  	dev_dbg(&pdev->xdev->dev, "Publishing pci roots\n");
>  
> -	err = xenbus_scanf(XBT_NULL, pdev->xdev->nodename,
> +	err = xenbus_scanf(XBT_NIL, pdev->xdev->nodename,
>  			   "root_num", "%d", &root_num);
>  	if (err == 0 || err == -ENOENT)
>  		root_num = 0;
> @@ -215,7 +215,7 @@ static int pciback_publish_pci_root(stru
>  			goto out;
>  		}
>  
> -		err = xenbus_scanf(XBT_NULL, pdev->xdev->nodename,
> +		err = xenbus_scanf(XBT_NIL, pdev->xdev->nodename,
>  				   str, "%x:%x", &d, &b);
>  		if (err < 0)
>  			goto out;
> @@ -239,12 +239,12 @@ static int pciback_publish_pci_root(stru
>  	dev_dbg(&pdev->xdev->dev, "writing root %d at %04x:%02x\n",
>  		root_num, domain, bus);
>  
> -	err = xenbus_printf(XBT_NULL, pdev->xdev->nodename, str,
> +	err = xenbus_printf(XBT_NIL, pdev->xdev->nodename, str,
>  			    "%04x:%02x", domain, bus);
>  	if (err)
>  		goto out;
>  
> -	err = xenbus_printf(XBT_NULL, pdev->xdev->nodename,
> +	err = xenbus_printf(XBT_NIL, pdev->xdev->nodename,
>  			    "root_num", "%d", (root_num + 1));
>  
>        out:
> @@ -306,7 +306,7 @@ static int pciback_setup_backend(struct 
>  
>  	dev_dbg(&pdev->xdev->dev, "getting be setup\n");
>  
> -	err = xenbus_scanf(XBT_NULL, pdev->xdev->nodename, "num_devs", "%d",
> +	err = xenbus_scanf(XBT_NIL, pdev->xdev->nodename, "num_devs", "%d",
>  			   &num_devs);
>  	if (err != 1) {
>  		if (err >= 0)
> @@ -326,7 +326,7 @@ static int pciback_setup_backend(struct 
>  			goto out;
>  		}
>  
> -		err = xenbus_scanf(XBT_NULL, pdev->xdev->nodename, dev_str,
> +		err = xenbus_scanf(XBT_NIL, pdev->xdev->nodename, dev_str,
>  				   "%x:%x:%x.%x", &domain, &bus, &slot, &func);
>  		if (err < 0) {
>  			xenbus_dev_fatal(pdev->xdev, err,
> diff -r 7cf4cbe7a3be -r 49f65e2b0f1c linux-2.6-xen-sparse/drivers/xen/pcifront/xenbus.c
> --- a/linux-2.6-xen-sparse/drivers/xen/pcifront/xenbus.c	Fri Jun 09 14:23:50 2006 +0100
> +++ b/linux-2.6-xen-sparse/drivers/xen/pcifront/xenbus.c	Fri Jun 09 14:25:46 2006 +0100
> @@ -67,7 +67,7 @@ static int pcifront_publish_info(struct 
>  static int pcifront_publish_info(struct pcifront_device *pdev)
>  {
>  	int err = 0;
> -	xenbus_transaction_t trans;
> +	struct xenbus_transaction trans;
>  
>  	err = xenbus_grant_ring(pdev->xdev, virt_to_mfn(pdev->sh_info));
>  	if (err < 0)
> @@ -143,7 +143,7 @@ static int pcifront_try_connect(struct p
>  		goto out;
>  	}
>  
> -	err = xenbus_scanf(XBT_NULL, pdev->xdev->otherend,
> +	err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
>  			   "root_num", "%d", &num_roots);
>  	if (err == -ENOENT) {
>  		xenbus_dev_error(pdev->xdev, err,
> @@ -165,7 +165,7 @@ static int pcifront_try_connect(struct p
>  			goto out;
>  		}
>  
> -		err = xenbus_scanf(XBT_NULL, pdev->xdev->otherend, str,
> +		err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
>  				   "%x:%x", &domain, &bus);
>  		if (err != 2) {
>  			if (err >= 0)
> diff -r 7cf4cbe7a3be -r 49f65e2b0f1c linux-2.6-xen-sparse/drivers/xen/tpmback/xenbus.c
> --- a/linux-2.6-xen-sparse/drivers/xen/tpmback/xenbus.c	Fri Jun 09 14:23:50 2006 +0100
> +++ b/linux-2.6-xen-sparse/drivers/xen/tpmback/xenbus.c	Fri Jun 09 14:25:46 2006 +0100
> @@ -110,7 +110,7 @@ static void backend_changed(struct xenbu
>  		= container_of(watch, struct backend_info, backend_watch);
>  	struct xenbus_device *dev = be->dev;
>  
> -	err = xenbus_scanf(XBT_NULL, dev->nodename,
> +	err = xenbus_scanf(XBT_NIL, dev->nodename,
>  	                   "instance","%li", &instance);
>  	if (XENBUS_EXIST_ERR(err)) {
>  		return;
> @@ -204,7 +204,7 @@ static void maybe_connect(struct backend
>  
>  static void connect(struct backend_info *be)
>  {
> -	xenbus_transaction_t xbt;
> +	struct xenbus_transaction xbt;
>  	int err;
>  	struct xenbus_device *dev = be->dev;
>  	unsigned long ready = 1;
> @@ -245,7 +245,7 @@ static int connect_ring(struct backend_i
>  	unsigned int evtchn;
>  	int err;
>  
> -	err = xenbus_gather(XBT_NULL, dev->otherend,
> +	err = xenbus_gather(XBT_NIL, dev->otherend,
>  	                    "ring-ref", "%lu", &ring_ref,
>  			    "event-channel", "%u", &evtchn, NULL);
>  	if (err) {
> diff -r 7cf4cbe7a3be -r 49f65e2b0f1c linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_client.c
> --- a/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_client.c	Fri Jun 09 14:23:50 2006 +0100
> +++ b/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_client.c	Fri Jun 09 14:25:46 2006 +0100
> @@ -106,12 +106,12 @@ int xenbus_switch_state(struct xenbus_de
>  	if (state == dev->state)
>  		return 0;
>  
> -	err = xenbus_scanf(XBT_NULL, dev->nodename, "state", "%d",
> +	err = xenbus_scanf(XBT_NIL, dev->nodename, "state", "%d",
>  			   &current_state);
>  	if (err != 1)
>  		return 0;
>  
> -	err = xenbus_printf(XBT_NULL, dev->nodename, "state", "%d", state);
> +	err = xenbus_printf(XBT_NIL, dev->nodename, "state", "%d", state);
>  	if (err) {
>  		if (state != XenbusStateClosing) /* Avoid looping */
>  			xenbus_dev_fatal(dev, err, "writing new state");
> @@ -162,7 +162,7 @@ void _dev_error(struct xenbus_device *de
>  		goto fail;
>  	}
>  
> -	if (xenbus_write(XBT_NULL, path_buffer, "error", printf_buffer) != 0) {
> +	if (xenbus_write(XBT_NIL, path_buffer, "error", printf_buffer) != 0) {
>  		printk("xenbus: failed to write error node for %s (%s)\n",
>  		       dev->nodename, printf_buffer);
>  		goto fail;
> @@ -272,7 +272,7 @@ enum xenbus_state xenbus_read_driver_sta
>  enum xenbus_state xenbus_read_driver_state(const char *path)
>  {
>  	enum xenbus_state result;
> -	int err = xenbus_gather(XBT_NULL, path, "state", "%d", &result, NULL);
> +	int err = xenbus_gather(XBT_NIL, path, "state", "%d", &result, NULL);
>  	if (err)
>  		result = XenbusStateClosed;
>  
> diff -r 7cf4cbe7a3be -r 49f65e2b0f1c linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_dev.c
> --- a/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_dev.c	Fri Jun 09 14:23:50 2006 +0100
> +++ b/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_dev.c	Fri Jun 09 14:25:46 2006 +0100
> @@ -51,7 +51,7 @@
>  
>  struct xenbus_dev_transaction {
>  	struct list_head list;
> -	xenbus_transaction_t handle;
> +	struct xenbus_transaction handle;
>  };
>  
>  struct xenbus_dev_data {
> @@ -154,11 +154,11 @@ static ssize_t xenbus_dev_write(struct f
>  		}
>  
>  		if (msg_type == XS_TRANSACTION_START) {
> -			trans->handle = simple_strtoul(reply, NULL, 0);
> +			trans->handle.id = simple_strtoul(reply, NULL, 0);
>  			list_add(&trans->list, &u->transactions);
>  		} else if (msg_type == XS_TRANSACTION_END) {
>  			list_for_each_entry(trans, &u->transactions, list)
> -				if (trans->handle == u->u.msg.tx_id)
> +				if (trans->handle.id == u->u.msg.tx_id)
>  					break;
>  			BUG_ON(&trans->list == &u->transactions);
>  			list_del(&trans->list);
> diff -r 7cf4cbe7a3be -r 49f65e2b0f1c linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_probe.c
> --- a/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_probe.c	Fri Jun 09 14:23:50 2006 +0100
> +++ b/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_probe.c	Fri Jun 09 14:25:46 2006 +0100
> @@ -128,7 +128,7 @@ static int read_otherend_details(struct 
>  static int read_otherend_details(struct xenbus_device *xendev,
>  				 char *id_node, char *path_node)
>  {
> -	int err = xenbus_gather(XBT_NULL, xendev->nodename,
> +	int err = xenbus_gather(XBT_NIL, xendev->nodename,
>  				id_node, "%i", &xendev->otherend_id,
>  				path_node, NULL, &xendev->otherend,
>  				NULL);
> @@ -139,7 +139,7 @@ static int read_otherend_details(struct 
>  		return err;
>  	}
>  	if (strlen(xendev->otherend) == 0 ||
> -	    !xenbus_exists(XBT_NULL, xendev->otherend, "")) {
> +	    !xenbus_exists(XBT_NIL, xendev->otherend, "")) {
>  		xenbus_dev_fatal(xendev, -ENOENT, "missing other end from %s",
>  				 xendev->nodename);
>  		free_otherend_details(xendev);
> @@ -195,14 +195,14 @@ static int backend_bus_id(char bus_id[BU
>  
>  	devid = strrchr(nodename, '/') + 1;
>  
> -	err = xenbus_gather(XBT_NULL, nodename, "frontend-id", "%i", &domid,
> +	err = xenbus_gather(XBT_NIL, nodename, "frontend-id", "%i", &domid,
>  			    "frontend", NULL, &frontend,
>  			    NULL);
>  	if (err)
>  		return err;
>  	if (strlen(frontend) == 0)
>  		err = -ERANGE;
> -	if (!err && !xenbus_exists(XBT_NULL, frontend, ""))
> +	if (!err && !xenbus_exists(XBT_NIL, frontend, ""))
>  		err = -ENOENT;
>  
>  	kfree(frontend);
> @@ -634,7 +634,7 @@ static int xenbus_probe_backend(const ch
>  	if (!nodename)
>  		return -ENOMEM;
>  
> -	dir = xenbus_directory(XBT_NULL, nodename, "", &dir_n);
> +	dir = xenbus_directory(XBT_NIL, nodename, "", &dir_n);
>  	if (IS_ERR(dir)) {
>  		kfree(nodename);
>  		return PTR_ERR(dir);
> @@ -657,7 +657,7 @@ static int xenbus_probe_device_type(stru
>  	unsigned int dir_n = 0;
>  	int i;
>  
> -	dir = xenbus_directory(XBT_NULL, bus->root, type, &dir_n);
> +	dir = xenbus_directory(XBT_NIL, bus->root, type, &dir_n);
>  	if (IS_ERR(dir))
>  		return PTR_ERR(dir);
>  
> @@ -676,7 +676,7 @@ static int xenbus_probe_devices(struct x
>  	char **dir;
>  	unsigned int i, dir_n;
>  
> -	dir = xenbus_directory(XBT_NULL, bus->root, "", &dir_n);
> +	dir = xenbus_directory(XBT_NIL, bus->root, "", &dir_n);
>  	if (IS_ERR(dir))
>  		return PTR_ERR(dir);
>  
> @@ -722,7 +722,7 @@ static void dev_changed(const char *node
>  	if (char_count(node, '/') < 2)
>   		return;
>  
> -	exists = xenbus_exists(XBT_NULL, node, "");
> +	exists = xenbus_exists(XBT_NIL, node, "");
>  	if (!exists) {
>  		xenbus_cleanup_devices(node, &bus->bus);
>  		return;
> diff -r 7cf4cbe7a3be -r 49f65e2b0f1c linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_xs.c
> --- a/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_xs.c	Fri Jun 09 14:23:50 2006 +0100
> +++ b/linux-2.6-xen-sparse/drivers/xen/xenbus/xenbus_xs.c	Fri Jun 09 14:25:46 2006 +0100
> @@ -192,7 +192,7 @@ void *xenbus_dev_request_and_reply(struc
>  }
>  
>  /* Send message to xs, get kmalloc'ed reply.  ERR_PTR() on error. */
> -static void *xs_talkv(xenbus_transaction_t t,
> +static void *xs_talkv(struct xenbus_transaction t,
>  		      enum xsd_sockmsg_type type,
>  		      const struct kvec *iovec,
>  		      unsigned int num_vecs,
> @@ -203,7 +203,7 @@ static void *xs_talkv(xenbus_transaction
>  	unsigned int i;
>  	int err;
>  
> -	msg.tx_id = t;
> +	msg.tx_id = t.id;
>  	msg.req_id = 0;
>  	msg.type = type;
>  	msg.len = 0;
> @@ -251,7 +251,7 @@ static void *xs_talkv(xenbus_transaction
>  }
>  
>  /* Simplified version of xs_talkv: single message. */
> -static void *xs_single(xenbus_transaction_t t,
> +static void *xs_single(struct xenbus_transaction t,
>  		       enum xsd_sockmsg_type type,
>  		       const char *string,
>  		       unsigned int *len)
> @@ -318,7 +318,7 @@ static char **split(char *strings, unsig
>  	return ret;
>  }
>  
> -char **xenbus_directory(xenbus_transaction_t t,
> +char **xenbus_directory(struct xenbus_transaction t,
>  			const char *dir, const char *node, unsigned int *num)
>  {
>  	char *strings, *path;
> @@ -338,7 +338,7 @@ EXPORT_SYMBOL_GPL(xenbus_directory);
>  EXPORT_SYMBOL_GPL(xenbus_directory);
>  
>  /* Check if a path exists. Return 1 if it does. */
> -int xenbus_exists(xenbus_transaction_t t,
> +int xenbus_exists(struct xenbus_transaction t,
>  		  const char *dir, const char *node)
>  {
>  	char **d;
> @@ -356,7 +356,7 @@ EXPORT_SYMBOL_GPL(xenbus_exists);
>   * Returns a kmalloced value: call free() on it after use.
>   * len indicates length in bytes.
>   */
> -void *xenbus_read(xenbus_transaction_t t,
> +void *xenbus_read(struct xenbus_transaction t,
>  		  const char *dir, const char *node, unsigned int *len)
>  {
>  	char *path;
> @@ -375,7 +375,7 @@ EXPORT_SYMBOL_GPL(xenbus_read);
>  /* Write the value of a single file.
>   * Returns -err on failure.
>   */
> -int xenbus_write(xenbus_transaction_t t,
> +int xenbus_write(struct xenbus_transaction t,
>  		 const char *dir, const char *node, const char *string)
>  {
>  	const char *path;
> @@ -398,7 +398,7 @@ EXPORT_SYMBOL_GPL(xenbus_write);
>  EXPORT_SYMBOL_GPL(xenbus_write);
>  
>  /* Create a new directory. */
> -int xenbus_mkdir(xenbus_transaction_t t,
> +int xenbus_mkdir(struct xenbus_transaction t,
>  		 const char *dir, const char *node)
>  {
>  	char *path;
> @@ -415,7 +415,7 @@ EXPORT_SYMBOL_GPL(xenbus_mkdir);
>  EXPORT_SYMBOL_GPL(xenbus_mkdir);
>  
>  /* Destroy a file or directory (directories must be empty). */
> -int xenbus_rm(xenbus_transaction_t t, const char *dir, const char *node)
> +int xenbus_rm(struct xenbus_transaction t, const char *dir, const char *node)
>  {
>  	char *path;
>  	int ret;
> @@ -433,19 +433,19 @@ EXPORT_SYMBOL_GPL(xenbus_rm);
>  /* Start a transaction: changes by others will not be seen during this
>   * transaction, and changes will not be visible to others until end.
>   */
> -int xenbus_transaction_start(xenbus_transaction_t *t)
> +int xenbus_transaction_start(struct xenbus_transaction *t)
>  {
>  	char *id_str;
>  
>  	down_read(&xs_state.suspend_mutex);
>  
> -	id_str = xs_single(XBT_NULL, XS_TRANSACTION_START, "", NULL);
> +	id_str = xs_single(XBT_NIL, XS_TRANSACTION_START, "", NULL);
>  	if (IS_ERR(id_str)) {
>  		up_read(&xs_state.suspend_mutex);
>  		return PTR_ERR(id_str);
>  	}
>  
> -	*t = simple_strtoul(id_str, NULL, 0);
> +	t->id = simple_strtoul(id_str, NULL, 0);
>  	kfree(id_str);
>  	return 0;
>  }
> @@ -454,7 +454,7 @@ EXPORT_SYMBOL_GPL(xenbus_transaction_sta
>  /* End a transaction.
>   * If abandon is true, transaction is discarded instead of committed.
>   */
> -int xenbus_transaction_end(xenbus_transaction_t t, int abort)
> +int xenbus_transaction_end(struct xenbus_transaction t, int abort)
>  {
>  	char abortstr[2];
>  	int err;
> @@ -473,7 +473,7 @@ EXPORT_SYMBOL_GPL(xenbus_transaction_end
>  EXPORT_SYMBOL_GPL(xenbus_transaction_end);
>  
>  /* Single read and scanf: returns -errno or num scanned. */
> -int xenbus_scanf(xenbus_transaction_t t,
> +int xenbus_scanf(struct xenbus_transaction t,
>  		 const char *dir, const char *node, const char *fmt, ...)
>  {
>  	va_list ap;
> @@ -496,7 +496,7 @@ EXPORT_SYMBOL_GPL(xenbus_scanf);
>  EXPORT_SYMBOL_GPL(xenbus_scanf);
>  
>  /* Single printf and write: returns -errno or 0. */
> -int xenbus_printf(xenbus_transaction_t t,
> +int xenbus_printf(struct xenbus_transaction t,
>  		  const char *dir, const char *node, const char *fmt, ...)
>  {
>  	va_list ap;
> @@ -522,7 +522,7 @@ EXPORT_SYMBOL_GPL(xenbus_printf);
>  EXPORT_SYMBOL_GPL(xenbus_printf);
>  
>  /* Takes tuples of names, scanf-style args, and void **, NULL terminated. */
> -int xenbus_gather(xenbus_transaction_t t, const char *dir, ...)
> +int xenbus_gather(struct xenbus_transaction t, const char *dir, ...)
>  {
>  	va_list ap;
>  	const char *name;
> @@ -560,7 +560,7 @@ static int xs_watch(const char *path, co
>  	iov[1].iov_base = (void *)token;
>  	iov[1].iov_len = strlen(token) + 1;
>  
> -	return xs_error(xs_talkv(XBT_NULL, XS_WATCH, iov,
> +	return xs_error(xs_talkv(XBT_NIL, XS_WATCH, iov,
>  				 ARRAY_SIZE(iov), NULL));
>  }
>  
> @@ -573,7 +573,7 @@ static int xs_unwatch(const char *path, 
>  	iov[1].iov_base = (char *)token;
>  	iov[1].iov_len = strlen(token) + 1;
>  
> -	return xs_error(xs_talkv(XBT_NULL, XS_UNWATCH, iov,
> +	return xs_error(xs_talkv(XBT_NIL, XS_UNWATCH, iov,
>  				 ARRAY_SIZE(iov), NULL));
>  }
>  
> diff -r 7cf4cbe7a3be -r 49f65e2b0f1c linux-2.6-xen-sparse/include/xen/xenbus.h
> --- a/linux-2.6-xen-sparse/include/xen/xenbus.h	Fri Jun 09 14:23:50 2006 +0100
> +++ b/linux-2.6-xen-sparse/include/xen/xenbus.h	Fri Jun 09 14:25:46 2006 +0100
> @@ -41,8 +41,6 @@
>  #include <xen/interface/grant_table.h>
>  #include <xen/interface/io/xenbus.h>
>  #include <xen/interface/io/xs_wire.h>
> -
> -#define XBT_NULL 0
>  
>  /* Register callback to watch this node. */
>  struct xenbus_watch
> @@ -115,35 +113,41 @@ int xenbus_register_backend(struct xenbu
>  int xenbus_register_backend(struct xenbus_driver *drv);
>  void xenbus_unregister_driver(struct xenbus_driver *drv);
>  
> -typedef u32 xenbus_transaction_t;
> -
> -char **xenbus_directory(xenbus_transaction_t t,
> +struct xenbus_transaction
> +{
> +	u32 id;
> +};
> +
> +/* Nil transaction ID. */
> +#define XBT_NIL ((struct xenbus_transaction) { 0 })
> +
> +char **xenbus_directory(struct xenbus_transaction t,
>  			const char *dir, const char *node, unsigned int *num);
> -void *xenbus_read(xenbus_transaction_t t,
> +void *xenbus_read(struct xenbus_transaction t,
>  		  const char *dir, const char *node, unsigned int *len);
> -int xenbus_write(xenbus_transaction_t t,
> +int xenbus_write(struct xenbus_transaction t,
>  		 const char *dir, const char *node, const char *string);
> -int xenbus_mkdir(xenbus_transaction_t t,
> +int xenbus_mkdir(struct xenbus_transaction t,
>  		 const char *dir, const char *node);
> -int xenbus_exists(xenbus_transaction_t t,
> +int xenbus_exists(struct xenbus_transaction t,
>  		  const char *dir, const char *node);
> -int xenbus_rm(xenbus_transaction_t t, const char *dir, const char *node);
> -int xenbus_transaction_start(xenbus_transaction_t *t);
> -int xenbus_transaction_end(xenbus_transaction_t t, int abort);
> +int xenbus_rm(struct xenbus_transaction t, const char *dir, const char *node);
> +int xenbus_transaction_start(struct xenbus_transaction *t);
> +int xenbus_transaction_end(struct xenbus_transaction t, int abort);
>  
>  /* Single read and scanf: returns -errno or num scanned if > 0. */
> -int xenbus_scanf(xenbus_transaction_t t,
> +int xenbus_scanf(struct xenbus_transaction t,
>  		 const char *dir, const char *node, const char *fmt, ...)
>  	__attribute__((format(scanf, 4, 5)));
>  
>  /* Single printf and write: returns -errno or 0. */
> -int xenbus_printf(xenbus_transaction_t t,
> +int xenbus_printf(struct xenbus_transaction t,
>  		  const char *dir, const char *node, const char *fmt, ...)
>  	__attribute__((format(printf, 4, 5)));
>  
>  /* Generic read function: NULL-terminated triples of name,
>   * sprintf-style type string, and pointer. Returns 0 or errno.*/
> -int xenbus_gather(xenbus_transaction_t t, const char *dir, ...);
> +int xenbus_gather(struct xenbus_transaction t, const char *dir, ...);
>  
>  /* notifer routines for when the xenstore comes up */
>  int register_xenstore_notifier(struct notifier_block *nb);
>
> _______________________________________________
> Xen-changelog mailing list
> Xen-changelog@lists.xensource.com
> http://lists.xensource.com/xen-changelog
>   

Re: Re: [Xen-changelog] [xen-unstable] [LINUX][XENBUS] replace xenbus_transaction_t with an opaque transaction ID.

[Chris Wright]

* Anthony Liguori (aliguori@us.ibm.com) wrote:
> Can't we just go back to the original semantics and s/XBT_NIL/NULL/g.  
> The whole reason XBT_NULL was introduced was that it switched to an 
> integer and NULL used to represent no transaction.

Don't think there's a semantic change here.  Just syntax.
And these opaque objects are passed by value not ref, so NULL wouldn't
be right.

thanks,
-chris