Merge tag 'virtio-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus

Pull virtio updates from Rusty Russell.

* tag 'virtio-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  virtio: fix typo in comment
  virtio-mmio: Devices parameter parsing
  virtio_blk: Drop unused request tracking list
  virtio-blk: Fix hot-unplug race in remove method
  virtio: Use ida to allocate virtio index
  virtio: balloon: separate out common code between remove and freeze functions
  virtio: balloon: drop restore_common()
  9p: disconnect channel when PCI device is removed
  virtio: update documentation to v0.9.5 of spec

5 files changed, 207 insertions, 32 deletions

diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 0d39f2f4294..693187df760 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -29,9 +29,6 @@ struct virtio_blk
 	/* The disk structure for the kernel. */
 	struct gendisk *disk;
 
-	/* Request tracking. */
-	struct list_head reqs;
-
 	mempool_t *pool;
 
 	/* Process context for config space updates */
@@ -55,7 +52,6 @@ struct virtio_blk
 
 struct virtblk_req
 {
-	struct list_head list;
 	struct request *req;
 	struct virtio_blk_outhdr out_hdr;
 	struct virtio_scsi_inhdr in_hdr;
@@ -99,7 +95,6 @@ static void blk_done(struct virtqueue *vq)
 		}
 
 		__blk_end_request_all(vbr->req, error);
-		list_del(&vbr->list);
 		mempool_free(vbr, vblk->pool);
 	}
 	/* In case queue is stopped waiting for more buffers. */
@@ -184,7 +179,6 @@ static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
 		return false;
 	}
 
-	list_add_tail(&vbr->list, &vblk->reqs);
 	return true;
 }
 
@@ -437,7 +431,6 @@ static int __devinit virtblk_probe(struct virtio_device *vdev)
 		goto out_free_index;
 	}
 
-	INIT_LIST_HEAD(&vblk->reqs);
 	spin_lock_init(&vblk->lock);
 	vblk->vdev = vdev;
 	vblk->sg_elems = sg_elems;
@@ -583,21 +576,29 @@ static void __devexit virtblk_remove(struct virtio_device *vdev)
 {
 	struct virtio_blk *vblk = vdev->priv;
 	int index = vblk->index;
+	struct virtblk_req *vbr;
+	unsigned long flags;
 
 	/* Prevent config work handler from accessing the device. */
 	mutex_lock(&vblk->config_lock);
 	vblk->config_enable = false;
 	mutex_unlock(&vblk->config_lock);
 
-	/* Nothing should be pending. */
-	BUG_ON(!list_empty(&vblk->reqs));
-
 	/* Stop all the virtqueues. */
 	vdev->config->reset(vdev);
 
 	flush_work(&vblk->config_work);
 
 	del_gendisk(vblk->disk);
+
+	/* Abort requests dispatched to driver. */
+	spin_lock_irqsave(&vblk->lock, flags);
+	while ((vbr = virtqueue_detach_unused_buf(vblk->vq))) {
+		__blk_end_request_all(vbr->req, -EIO);
+		mempool_free(vbr, vblk->pool);
+	}
+	spin_unlock_irqrestore(&vblk->lock, flags);
+
 	blk_cleanup_queue(vblk->disk->queue);
 	put_disk(vblk->disk);
 	mempool_destroy(vblk->pool);
diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig
index 1a61939b85f..f38b17a86c3 100644
--- a/drivers/virtio/Kconfig
+++ b/drivers/virtio/Kconfig
@@ -46,4 +46,15 @@ config VIRTIO_BALLOON
 
  	 If unsure, say N.
 
+config VIRTIO_MMIO_CMDLINE_DEVICES
+	bool "Memory mapped virtio devices parameter parsing"
+	depends on VIRTIO_MMIO
+	---help---
+	 Allow virtio-mmio devices instantiation via the kernel command line
+	 or module parameters. Be aware that using incorrect parameters (base
+	 address in particular) can crash your system - you have been warned.
+	 See Documentation/kernel-parameters.txt for details.
+
+	 If unsure, say 'N'.
+
 endmenu
diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index 984c501c258..f3558070e37 100644
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -2,9 +2,10 @@
 #include <linux/spinlock.h>
 #include <linux/virtio_config.h>
 #include <linux/module.h>
+#include <linux/idr.h>
 
 /* Unique numbering for virtio devices. */
-static unsigned int dev_index;
+static DEFINE_IDA(virtio_index_ida);
 
 static ssize_t device_show(struct device *_d,
 			   struct device_attribute *attr, char *buf)
@@ -193,7 +194,11 @@ int register_virtio_device(struct virtio_device *dev)
 	dev->dev.bus = &virtio_bus;
 
 	/* Assign a unique device index and hence name. */
-	dev->index = dev_index++;
+	err = ida_simple_get(&virtio_index_ida, 0, 0, GFP_KERNEL);
+	if (err < 0)
+		goto out;
+
+	dev->index = err;
 	dev_set_name(&dev->dev, "virtio%u", dev->index);
 
 	/* We always start by resetting the device, in case a previous
@@ -208,6 +213,7 @@ int register_virtio_device(struct virtio_device *dev)
 	/* device_register() causes the bus infrastructure to look for a
 	 * matching driver. */
 	err = device_register(&dev->dev);
+out:
 	if (err)
 		add_status(dev, VIRTIO_CONFIG_S_FAILED);
 	return err;
@@ -217,6 +223,7 @@ EXPORT_SYMBOL_GPL(register_virtio_device);
 void unregister_virtio_device(struct virtio_device *dev)
 {
 	device_unregister(&dev->dev);
+	ida_simple_remove(&virtio_index_ida, dev->index);
 }
 EXPORT_SYMBOL_GPL(unregister_virtio_device);
 
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 8807fe501d2..bfbc15ca38d 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -381,21 +381,25 @@ out:
 	return err;
 }
 
-static void __devexit virtballoon_remove(struct virtio_device *vdev)
+static void remove_common(struct virtio_balloon *vb)
 {
-	struct virtio_balloon *vb = vdev->priv;
-
-	kthread_stop(vb->thread);
-
 	/* There might be pages left in the balloon: free them. */
 	while (vb->num_pages)
 		leak_balloon(vb, vb->num_pages);
 	update_balloon_size(vb);
 
 	/* Now we reset the device so we can clean up the queues. */
-	vdev->config->reset(vdev);
+	vb->vdev->config->reset(vb->vdev);
 
-	vdev->config->del_vqs(vdev);
+	vb->vdev->config->del_vqs(vb->vdev);
+}
+
+static void __devexit virtballoon_remove(struct virtio_device *vdev)
+{
+	struct virtio_balloon *vb = vdev->priv;
+
+	kthread_stop(vb->thread);
+	remove_common(vb);
 	kfree(vb);
 }
 
@@ -409,17 +413,11 @@ static int virtballoon_freeze(struct virtio_device *vdev)
 	 * function is called.
 	 */
 
-	while (vb->num_pages)
-		leak_balloon(vb, vb->num_pages);
-	update_balloon_size(vb);
-
-	/* Ensure we don't get any more requests from the host */
-	vdev->config->reset(vdev);
-	vdev->config->del_vqs(vdev);
+	remove_common(vb);
 	return 0;
 }
 
-static int restore_common(struct virtio_device *vdev)
+static int virtballoon_restore(struct virtio_device *vdev)
 {
 	struct virtio_balloon *vb = vdev->priv;
 	int ret;
@@ -432,11 +430,6 @@ static int restore_common(struct virtio_device *vdev)
 	update_balloon_size(vb);
 	return 0;
 }
-
-static int virtballoon_restore(struct virtio_device *vdev)
-{
-	return restore_common(vdev);
-}
 #endif
 
 static unsigned int features[] = {
diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
index 01d6dc250d5..453db0c403d 100644
--- a/drivers/virtio/virtio_mmio.c
+++ b/drivers/virtio/virtio_mmio.c
@@ -6,6 +6,50 @@
  * This module allows virtio devices to be used over a virtual, memory mapped
  * platform device.
  *
+ * The guest device(s) may be instantiated in one of three equivalent ways:
+ *
+ * 1. Static platform device in board's code, eg.:
+ *
+ *	static struct platform_device v2m_virtio_device = {
+ *		.name = "virtio-mmio",
+ *		.id = -1,
+ *		.num_resources = 2,
+ *		.resource = (struct resource []) {
+ *			{
+ *				.start = 0x1001e000,
+ *				.end = 0x1001e0ff,
+ *				.flags = IORESOURCE_MEM,
+ *			}, {
+ *				.start = 42 + 32,
+ *				.end = 42 + 32,
+ *				.flags = IORESOURCE_IRQ,
+ *			},
+ *		}
+ *	};
+ *
+ * 2. Device Tree node, eg.:
+ *
+ *		virtio_block@1e000 {
+ *			compatible = "virtio,mmio";
+ *			reg = <0x1e000 0x100>;
+ *			interrupts = <42>;
+ *		}
+ *
+ * 3. Kernel module (or command line) parameter. Can be used more than once -
+ *    one device will be created for each one. Syntax:
+ *
+ *		[virtio_mmio.]device=<size>@<baseaddr>:<irq>[:<id>]
+ *    where:
+ *		<size>     := size (can use standard suffixes like K, M or G)
+ *		<baseaddr> := physical base address
+ *		<irq>      := interrupt number (as passed to request_irq())
+ *		<id>       := (optional) platform device id
+ *    eg.:
+ *		virtio_mmio.device=0x100@0x100b0000:48 \
+ *				virtio_mmio.device=1K@0x1001e000:74
+ *
+ *
+ *
  * Registers layout (all 32-bit wide):
  *
  * offset d. name             description
@@ -42,6 +86,8 @@
  * See the COPYING file in the top-level directory.
  */
 
+#define pr_fmt(fmt) "virtio-mmio: " fmt
+
 #include <linux/highmem.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
@@ -449,6 +495,122 @@ static int __devexit virtio_mmio_remove(struct platform_device *pdev)
 
 
 
+/* Devices list parameter */
+
+#if defined(CONFIG_VIRTIO_MMIO_CMDLINE_DEVICES)
+
+static struct device vm_cmdline_parent = {
+	.init_name = "virtio-mmio-cmdline",
+};
+
+static int vm_cmdline_parent_registered;
+static int vm_cmdline_id;
+
+static int vm_cmdline_set(const char *device,
+		const struct kernel_param *kp)
+{
+	int err;
+	struct resource resources[2] = {};
+	char *str;
+	long long int base;
+	int processed, consumed = 0;
+	struct platform_device *pdev;
+
+	resources[0].flags = IORESOURCE_MEM;
+	resources[1].flags = IORESOURCE_IRQ;
+
+	resources[0].end = memparse(device, &str) - 1;
+
+	processed = sscanf(str, "@%lli:%u%n:%d%n",
+			&base, &resources[1].start, &consumed,
+			&vm_cmdline_id, &consumed);
+
+	if (processed < 2 || processed > 3 || str[consumed])
+		return -EINVAL;
+
+	resources[0].start = base;
+	resources[0].end += base;
+	resources[1].end = resources[1].start;
+
+	if (!vm_cmdline_parent_registered) {
+		err = device_register(&vm_cmdline_parent);
+		if (err) {
+			pr_err("Failed to register parent device!\n");
+			return err;
+		}
+		vm_cmdline_parent_registered = 1;
+	}
+
+	pr_info("Registering device virtio-mmio.%d at 0x%llx-0x%llx, IRQ %d.\n",
+		       vm_cmdline_id,
+		       (unsigned long long)resources[0].start,
+		       (unsigned long long)resources[0].end,
+		       (int)resources[1].start);
+
+	pdev = platform_device_register_resndata(&vm_cmdline_parent,
+			"virtio-mmio", vm_cmdline_id++,
+			resources, ARRAY_SIZE(resources), NULL, 0);
+	if (IS_ERR(pdev))
+		return PTR_ERR(pdev);
+
+	return 0;
+}
+
+static int vm_cmdline_get_device(struct device *dev, void *data)
+{
+	char *buffer = data;
+	unsigned int len = strlen(buffer);
+	struct platform_device *pdev = to_platform_device(dev);
+
+	snprintf(buffer + len, PAGE_SIZE - len, "0x%llx@0x%llx:%llu:%d\n",
+			pdev->resource[0].end - pdev->resource[0].start + 1ULL,
+			(unsigned long long)pdev->resource[0].start,
+			(unsigned long long)pdev->resource[1].start,
+			pdev->id);
+	return 0;
+}
+
+static int vm_cmdline_get(char *buffer, const struct kernel_param *kp)
+{
+	buffer[0] = '\0';
+	device_for_each_child(&vm_cmdline_parent, buffer,
+			vm_cmdline_get_device);
+	return strlen(buffer) + 1;
+}
+
+static struct kernel_param_ops vm_cmdline_param_ops = {
+	.set = vm_cmdline_set,
+	.get = vm_cmdline_get,
+};
+
+device_param_cb(device, &vm_cmdline_param_ops, NULL, S_IRUSR);
+
+static int vm_unregister_cmdline_device(struct device *dev,
+		void *data)
+{
+	platform_device_unregister(to_platform_device(dev));
+
+	return 0;
+}
+
+static void vm_unregister_cmdline_devices(void)
+{
+	if (vm_cmdline_parent_registered) {
+		device_for_each_child(&vm_cmdline_parent, NULL,
+				vm_unregister_cmdline_device);
+		device_unregister(&vm_cmdline_parent);
+		vm_cmdline_parent_registered = 0;
+	}
+}
+
+#else
+
+static void vm_unregister_cmdline_devices(void)
+{
+}
+
+#endif
+
 /* Platform driver */
 
 static struct of_device_id virtio_mmio_match[] = {
@@ -475,6 +637,7 @@ static int __init virtio_mmio_init(void)
 static void __exit virtio_mmio_exit(void)
 {
 	platform_driver_unregister(&virtio_mmio_driver);
+	vm_unregister_cmdline_devices();
 }
 
 module_init(virtio_mmio_init);