diff options
Diffstat (limited to 'drivers/virt/fsl_hypervisor.c')
| -rw-r--r-- | drivers/virt/fsl_hypervisor.c | 937 | 
1 files changed, 937 insertions, 0 deletions
diff --git a/drivers/virt/fsl_hypervisor.c b/drivers/virt/fsl_hypervisor.c new file mode 100644 index 00000000000..32c8fc5f7a5 --- /dev/null +++ b/drivers/virt/fsl_hypervisor.c @@ -0,0 +1,937 @@ +/* + * Freescale Hypervisor Management Driver + + * Copyright (C) 2008-2011 Freescale Semiconductor, Inc. + * Author: Timur Tabi <timur@freescale.com> + * + * This file is licensed under the terms of the GNU General Public License + * version 2.  This program is licensed "as is" without any warranty of any + * kind, whether express or implied. + * + * The Freescale hypervisor management driver provides several services to + * drivers and applications related to the Freescale hypervisor: + * + * 1. An ioctl interface for querying and managing partitions. + * + * 2. A file interface to reading incoming doorbells. + * + * 3. An interrupt handler for shutting down the partition upon receiving the + *    shutdown doorbell from a manager partition. + * + * 4. A kernel interface for receiving callbacks when a managed partition + *    shuts down. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/types.h> +#include <linux/err.h> +#include <linux/fs.h> +#include <linux/miscdevice.h> +#include <linux/mm.h> +#include <linux/pagemap.h> +#include <linux/slab.h> +#include <linux/poll.h> +#include <linux/of.h> +#include <linux/of_irq.h> +#include <linux/reboot.h> +#include <linux/uaccess.h> +#include <linux/notifier.h> +#include <linux/interrupt.h> + +#include <linux/io.h> +#include <asm/fsl_hcalls.h> + +#include <linux/fsl_hypervisor.h> + +static BLOCKING_NOTIFIER_HEAD(failover_subscribers); + +/* + * Ioctl interface for FSL_HV_IOCTL_PARTITION_RESTART + * + * Restart a running partition + */ +static long ioctl_restart(struct fsl_hv_ioctl_restart __user *p) +{ +	struct fsl_hv_ioctl_restart param; + +	/* Get the parameters from the user */ +	if (copy_from_user(¶m, p, sizeof(struct fsl_hv_ioctl_restart))) +		return -EFAULT; + +	param.ret = fh_partition_restart(param.partition); + +	if (copy_to_user(&p->ret, ¶m.ret, sizeof(__u32))) +		return -EFAULT; + +	return 0; +} + +/* + * Ioctl interface for FSL_HV_IOCTL_PARTITION_STATUS + * + * Query the status of a partition + */ +static long ioctl_status(struct fsl_hv_ioctl_status __user *p) +{ +	struct fsl_hv_ioctl_status param; +	u32 status; + +	/* Get the parameters from the user */ +	if (copy_from_user(¶m, p, sizeof(struct fsl_hv_ioctl_status))) +		return -EFAULT; + +	param.ret = fh_partition_get_status(param.partition, &status); +	if (!param.ret) +		param.status = status; + +	if (copy_to_user(p, ¶m, sizeof(struct fsl_hv_ioctl_status))) +		return -EFAULT; + +	return 0; +} + +/* + * Ioctl interface for FSL_HV_IOCTL_PARTITION_START + * + * Start a stopped partition. + */ +static long ioctl_start(struct fsl_hv_ioctl_start __user *p) +{ +	struct fsl_hv_ioctl_start param; + +	/* Get the parameters from the user */ +	if (copy_from_user(¶m, p, sizeof(struct fsl_hv_ioctl_start))) +		return -EFAULT; + +	param.ret = fh_partition_start(param.partition, param.entry_point, +				       param.load); + +	if (copy_to_user(&p->ret, ¶m.ret, sizeof(__u32))) +		return -EFAULT; + +	return 0; +} + +/* + * Ioctl interface for FSL_HV_IOCTL_PARTITION_STOP + * + * Stop a running partition + */ +static long ioctl_stop(struct fsl_hv_ioctl_stop __user *p) +{ +	struct fsl_hv_ioctl_stop param; + +	/* Get the parameters from the user */ +	if (copy_from_user(¶m, p, sizeof(struct fsl_hv_ioctl_stop))) +		return -EFAULT; + +	param.ret = fh_partition_stop(param.partition); + +	if (copy_to_user(&p->ret, ¶m.ret, sizeof(__u32))) +		return -EFAULT; + +	return 0; +} + +/* + * Ioctl interface for FSL_HV_IOCTL_MEMCPY + * + * The FH_MEMCPY hypercall takes an array of address/address/size structures + * to represent the data being copied.  As a convenience to the user, this + * ioctl takes a user-create buffer and a pointer to a guest physically + * contiguous buffer in the remote partition, and creates the + * address/address/size array for the hypercall. + */ +static long ioctl_memcpy(struct fsl_hv_ioctl_memcpy __user *p) +{ +	struct fsl_hv_ioctl_memcpy param; + +	struct page **pages = NULL; +	void *sg_list_unaligned = NULL; +	struct fh_sg_list *sg_list = NULL; + +	unsigned int num_pages; +	unsigned long lb_offset; /* Offset within a page of the local buffer */ + +	unsigned int i; +	long ret = 0; +	int num_pinned; /* return value from get_user_pages() */ +	phys_addr_t remote_paddr; /* The next address in the remote buffer */ +	uint32_t count; /* The number of bytes left to copy */ + +	/* Get the parameters from the user */ +	if (copy_from_user(¶m, p, sizeof(struct fsl_hv_ioctl_memcpy))) +		return -EFAULT; + +	/* +	 * One partition must be local, the other must be remote.  In other +	 * words, if source and target are both -1, or are both not -1, then +	 * return an error. +	 */ +	if ((param.source == -1) == (param.target == -1)) +		return -EINVAL; + +	/* +	 * The array of pages returned by get_user_pages() covers only +	 * page-aligned memory.  Since the user buffer is probably not +	 * page-aligned, we need to handle the discrepancy. +	 * +	 * We calculate the offset within a page of the S/G list, and make +	 * adjustments accordingly.  This will result in a page list that looks +	 * like this: +	 * +	 *      ----    <-- first page starts before the buffer +	 *     |    | +	 *     |////|-> ---- +	 *     |////|  |    | +	 *      ----   |    | +	 *             |    | +	 *      ----   |    | +	 *     |////|  |    | +	 *     |////|  |    | +	 *     |////|  |    | +	 *      ----   |    | +	 *             |    | +	 *      ----   |    | +	 *     |////|  |    | +	 *     |////|  |    | +	 *     |////|  |    | +	 *      ----   |    | +	 *             |    | +	 *      ----   |    | +	 *     |////|  |    | +	 *     |////|-> ---- +	 *     |    |   <-- last page ends after the buffer +	 *      ---- +	 * +	 * The distance between the start of the first page and the start of the +	 * buffer is lb_offset.  The hashed (///) areas are the parts of the +	 * page list that contain the actual buffer. +	 * +	 * The advantage of this approach is that the number of pages is +	 * equal to the number of entries in the S/G list that we give to the +	 * hypervisor. +	 */ +	lb_offset = param.local_vaddr & (PAGE_SIZE - 1); +	num_pages = (param.count + lb_offset + PAGE_SIZE - 1) >> PAGE_SHIFT; + +	/* Allocate the buffers we need */ + +	/* +	 * 'pages' is an array of struct page pointers that's initialized by +	 * get_user_pages(). +	 */ +	pages = kzalloc(num_pages * sizeof(struct page *), GFP_KERNEL); +	if (!pages) { +		pr_debug("fsl-hv: could not allocate page list\n"); +		return -ENOMEM; +	} + +	/* +	 * sg_list is the list of fh_sg_list objects that we pass to the +	 * hypervisor. +	 */ +	sg_list_unaligned = kmalloc(num_pages * sizeof(struct fh_sg_list) + +		sizeof(struct fh_sg_list) - 1, GFP_KERNEL); +	if (!sg_list_unaligned) { +		pr_debug("fsl-hv: could not allocate S/G list\n"); +		ret = -ENOMEM; +		goto exit; +	} +	sg_list = PTR_ALIGN(sg_list_unaligned, sizeof(struct fh_sg_list)); + +	/* Get the physical addresses of the source buffer */ +	down_read(¤t->mm->mmap_sem); +	num_pinned = get_user_pages(current, current->mm, +		param.local_vaddr - lb_offset, num_pages, +		(param.source == -1) ? READ : WRITE, +		0, pages, NULL); +	up_read(¤t->mm->mmap_sem); + +	if (num_pinned != num_pages) { +		/* get_user_pages() failed */ +		pr_debug("fsl-hv: could not lock source buffer\n"); +		ret = (num_pinned < 0) ? num_pinned : -EFAULT; +		goto exit; +	} + +	/* +	 * Build the fh_sg_list[] array.  The first page is special +	 * because it's misaligned. +	 */ +	if (param.source == -1) { +		sg_list[0].source = page_to_phys(pages[0]) + lb_offset; +		sg_list[0].target = param.remote_paddr; +	} else { +		sg_list[0].source = param.remote_paddr; +		sg_list[0].target = page_to_phys(pages[0]) + lb_offset; +	} +	sg_list[0].size = min_t(uint64_t, param.count, PAGE_SIZE - lb_offset); + +	remote_paddr = param.remote_paddr + sg_list[0].size; +	count = param.count - sg_list[0].size; + +	for (i = 1; i < num_pages; i++) { +		if (param.source == -1) { +			/* local to remote */ +			sg_list[i].source = page_to_phys(pages[i]); +			sg_list[i].target = remote_paddr; +		} else { +			/* remote to local */ +			sg_list[i].source = remote_paddr; +			sg_list[i].target = page_to_phys(pages[i]); +		} +		sg_list[i].size = min_t(uint64_t, count, PAGE_SIZE); + +		remote_paddr += sg_list[i].size; +		count -= sg_list[i].size; +	} + +	param.ret = fh_partition_memcpy(param.source, param.target, +		virt_to_phys(sg_list), num_pages); + +exit: +	if (pages) { +		for (i = 0; i < num_pages; i++) +			if (pages[i]) +				put_page(pages[i]); +	} + +	kfree(sg_list_unaligned); +	kfree(pages); + +	if (!ret) +		if (copy_to_user(&p->ret, ¶m.ret, sizeof(__u32))) +			return -EFAULT; + +	return ret; +} + +/* + * Ioctl interface for FSL_HV_IOCTL_DOORBELL + * + * Ring a doorbell + */ +static long ioctl_doorbell(struct fsl_hv_ioctl_doorbell __user *p) +{ +	struct fsl_hv_ioctl_doorbell param; + +	/* Get the parameters from the user. */ +	if (copy_from_user(¶m, p, sizeof(struct fsl_hv_ioctl_doorbell))) +		return -EFAULT; + +	param.ret = ev_doorbell_send(param.doorbell); + +	if (copy_to_user(&p->ret, ¶m.ret, sizeof(__u32))) +		return -EFAULT; + +	return 0; +} + +static long ioctl_dtprop(struct fsl_hv_ioctl_prop __user *p, int set) +{ +	struct fsl_hv_ioctl_prop param; +	char __user *upath, *upropname; +	void __user *upropval; +	char *path = NULL, *propname = NULL; +	void *propval = NULL; +	int ret = 0; + +	/* Get the parameters from the user. */ +	if (copy_from_user(¶m, p, sizeof(struct fsl_hv_ioctl_prop))) +		return -EFAULT; + +	upath = (char __user *)(uintptr_t)param.path; +	upropname = (char __user *)(uintptr_t)param.propname; +	upropval = (void __user *)(uintptr_t)param.propval; + +	path = strndup_user(upath, FH_DTPROP_MAX_PATHLEN); +	if (IS_ERR(path)) { +		ret = PTR_ERR(path); +		goto out; +	} + +	propname = strndup_user(upropname, FH_DTPROP_MAX_PATHLEN); +	if (IS_ERR(propname)) { +		ret = PTR_ERR(propname); +		goto out; +	} + +	if (param.proplen > FH_DTPROP_MAX_PROPLEN) { +		ret = -EINVAL; +		goto out; +	} + +	propval = kmalloc(param.proplen, GFP_KERNEL); +	if (!propval) { +		ret = -ENOMEM; +		goto out; +	} + +	if (set) { +		if (copy_from_user(propval, upropval, param.proplen)) { +			ret = -EFAULT; +			goto out; +		} + +		param.ret = fh_partition_set_dtprop(param.handle, +						    virt_to_phys(path), +						    virt_to_phys(propname), +						    virt_to_phys(propval), +						    param.proplen); +	} else { +		param.ret = fh_partition_get_dtprop(param.handle, +						    virt_to_phys(path), +						    virt_to_phys(propname), +						    virt_to_phys(propval), +						    ¶m.proplen); + +		if (param.ret == 0) { +			if (copy_to_user(upropval, propval, param.proplen) || +			    put_user(param.proplen, &p->proplen)) { +				ret = -EFAULT; +				goto out; +			} +		} +	} + +	if (put_user(param.ret, &p->ret)) +		ret = -EFAULT; + +out: +	kfree(path); +	kfree(propval); +	kfree(propname); + +	return ret; +} + +/* + * Ioctl main entry point + */ +static long fsl_hv_ioctl(struct file *file, unsigned int cmd, +			 unsigned long argaddr) +{ +	void __user *arg = (void __user *)argaddr; +	long ret; + +	switch (cmd) { +	case FSL_HV_IOCTL_PARTITION_RESTART: +		ret = ioctl_restart(arg); +		break; +	case FSL_HV_IOCTL_PARTITION_GET_STATUS: +		ret = ioctl_status(arg); +		break; +	case FSL_HV_IOCTL_PARTITION_START: +		ret = ioctl_start(arg); +		break; +	case FSL_HV_IOCTL_PARTITION_STOP: +		ret = ioctl_stop(arg); +		break; +	case FSL_HV_IOCTL_MEMCPY: +		ret = ioctl_memcpy(arg); +		break; +	case FSL_HV_IOCTL_DOORBELL: +		ret = ioctl_doorbell(arg); +		break; +	case FSL_HV_IOCTL_GETPROP: +		ret = ioctl_dtprop(arg, 0); +		break; +	case FSL_HV_IOCTL_SETPROP: +		ret = ioctl_dtprop(arg, 1); +		break; +	default: +		pr_debug("fsl-hv: bad ioctl dir=%u type=%u cmd=%u size=%u\n", +			 _IOC_DIR(cmd), _IOC_TYPE(cmd), _IOC_NR(cmd), +			 _IOC_SIZE(cmd)); +		return -ENOTTY; +	} + +	return ret; +} + +/* Linked list of processes that have us open */ +static struct list_head db_list; + +/* spinlock for db_list */ +static DEFINE_SPINLOCK(db_list_lock); + +/* The size of the doorbell event queue.  This must be a power of two. */ +#define QSIZE	16 + +/* Returns the next head/tail pointer, wrapping around the queue if necessary */ +#define nextp(x) (((x) + 1) & (QSIZE - 1)) + +/* Per-open data structure */ +struct doorbell_queue { +	struct list_head list; +	spinlock_t lock; +	wait_queue_head_t wait; +	unsigned int head; +	unsigned int tail; +	uint32_t q[QSIZE]; +}; + +/* Linked list of ISRs that we registered */ +struct list_head isr_list; + +/* Per-ISR data structure */ +struct doorbell_isr { +	struct list_head list; +	unsigned int irq; +	uint32_t doorbell;	/* The doorbell handle */ +	uint32_t partition;	/* The partition handle, if used */ +}; + +/* + * Add a doorbell to all of the doorbell queues + */ +static void fsl_hv_queue_doorbell(uint32_t doorbell) +{ +	struct doorbell_queue *dbq; +	unsigned long flags; + +	/* Prevent another core from modifying db_list */ +	spin_lock_irqsave(&db_list_lock, flags); + +	list_for_each_entry(dbq, &db_list, list) { +		if (dbq->head != nextp(dbq->tail)) { +			dbq->q[dbq->tail] = doorbell; +			/* +			 * This memory barrier eliminates the need to grab +			 * the spinlock for dbq. +			 */ +			smp_wmb(); +			dbq->tail = nextp(dbq->tail); +			wake_up_interruptible(&dbq->wait); +		} +	} + +	spin_unlock_irqrestore(&db_list_lock, flags); +} + +/* + * Interrupt handler for all doorbells + * + * We use the same interrupt handler for all doorbells.  Whenever a doorbell + * is rung, and we receive an interrupt, we just put the handle for that + * doorbell (passed to us as *data) into all of the queues. + */ +static irqreturn_t fsl_hv_isr(int irq, void *data) +{ +	fsl_hv_queue_doorbell((uintptr_t) data); + +	return IRQ_HANDLED; +} + +/* + * State change thread function + * + * The state change notification arrives in an interrupt, but we can't call + * blocking_notifier_call_chain() in an interrupt handler.  We could call + * atomic_notifier_call_chain(), but that would require the clients' call-back + * function to run in interrupt context.  Since we don't want to impose that + * restriction on the clients, we use a threaded IRQ to process the + * notification in kernel context. + */ +static irqreturn_t fsl_hv_state_change_thread(int irq, void *data) +{ +	struct doorbell_isr *dbisr = data; + +	blocking_notifier_call_chain(&failover_subscribers, dbisr->partition, +				     NULL); + +	return IRQ_HANDLED; +} + +/* + * Interrupt handler for state-change doorbells + */ +static irqreturn_t fsl_hv_state_change_isr(int irq, void *data) +{ +	unsigned int status; +	struct doorbell_isr *dbisr = data; +	int ret; + +	/* It's still a doorbell, so add it to all the queues. */ +	fsl_hv_queue_doorbell(dbisr->doorbell); + +	/* Determine the new state, and if it's stopped, notify the clients. */ +	ret = fh_partition_get_status(dbisr->partition, &status); +	if (!ret && (status == FH_PARTITION_STOPPED)) +		return IRQ_WAKE_THREAD; + +	return IRQ_HANDLED; +} + +/* + * Returns a bitmask indicating whether a read will block + */ +static unsigned int fsl_hv_poll(struct file *filp, struct poll_table_struct *p) +{ +	struct doorbell_queue *dbq = filp->private_data; +	unsigned long flags; +	unsigned int mask; + +	spin_lock_irqsave(&dbq->lock, flags); + +	poll_wait(filp, &dbq->wait, p); +	mask = (dbq->head == dbq->tail) ? 0 : (POLLIN | POLLRDNORM); + +	spin_unlock_irqrestore(&dbq->lock, flags); + +	return mask; +} + +/* + * Return the handles for any incoming doorbells + * + * If there are doorbell handles in the queue for this open instance, then + * return them to the caller as an array of 32-bit integers.  Otherwise, + * block until there is at least one handle to return. + */ +static ssize_t fsl_hv_read(struct file *filp, char __user *buf, size_t len, +			   loff_t *off) +{ +	struct doorbell_queue *dbq = filp->private_data; +	uint32_t __user *p = (uint32_t __user *) buf; /* for put_user() */ +	unsigned long flags; +	ssize_t count = 0; + +	/* Make sure we stop when the user buffer is full. */ +	while (len >= sizeof(uint32_t)) { +		uint32_t dbell;	/* Local copy of doorbell queue data */ + +		spin_lock_irqsave(&dbq->lock, flags); + +		/* +		 * If the queue is empty, then either we're done or we need +		 * to block.  If the application specified O_NONBLOCK, then +		 * we return the appropriate error code. +		 */ +		if (dbq->head == dbq->tail) { +			spin_unlock_irqrestore(&dbq->lock, flags); +			if (count) +				break; +			if (filp->f_flags & O_NONBLOCK) +				return -EAGAIN; +			if (wait_event_interruptible(dbq->wait, +						     dbq->head != dbq->tail)) +				return -ERESTARTSYS; +			continue; +		} + +		/* +		 * Even though we have an smp_wmb() in the ISR, the core +		 * might speculatively execute the "dbell = ..." below while +		 * it's evaluating the if-statement above.  In that case, the +		 * value put into dbell could be stale if the core accepts the +		 * speculation. To prevent that, we need a read memory barrier +		 * here as well. +		 */ +		smp_rmb(); + +		/* Copy the data to a temporary local buffer, because +		 * we can't call copy_to_user() from inside a spinlock +		 */ +		dbell = dbq->q[dbq->head]; +		dbq->head = nextp(dbq->head); + +		spin_unlock_irqrestore(&dbq->lock, flags); + +		if (put_user(dbell, p)) +			return -EFAULT; +		p++; +		count += sizeof(uint32_t); +		len -= sizeof(uint32_t); +	} + +	return count; +} + +/* + * Open the driver and prepare for reading doorbells. + * + * Every time an application opens the driver, we create a doorbell queue + * for that file handle.  This queue is used for any incoming doorbells. + */ +static int fsl_hv_open(struct inode *inode, struct file *filp) +{ +	struct doorbell_queue *dbq; +	unsigned long flags; +	int ret = 0; + +	dbq = kzalloc(sizeof(struct doorbell_queue), GFP_KERNEL); +	if (!dbq) { +		pr_err("fsl-hv: out of memory\n"); +		return -ENOMEM; +	} + +	spin_lock_init(&dbq->lock); +	init_waitqueue_head(&dbq->wait); + +	spin_lock_irqsave(&db_list_lock, flags); +	list_add(&dbq->list, &db_list); +	spin_unlock_irqrestore(&db_list_lock, flags); + +	filp->private_data = dbq; + +	return ret; +} + +/* + * Close the driver + */ +static int fsl_hv_close(struct inode *inode, struct file *filp) +{ +	struct doorbell_queue *dbq = filp->private_data; +	unsigned long flags; + +	int ret = 0; + +	spin_lock_irqsave(&db_list_lock, flags); +	list_del(&dbq->list); +	spin_unlock_irqrestore(&db_list_lock, flags); + +	kfree(dbq); + +	return ret; +} + +static const struct file_operations fsl_hv_fops = { +	.owner = THIS_MODULE, +	.open = fsl_hv_open, +	.release = fsl_hv_close, +	.poll = fsl_hv_poll, +	.read = fsl_hv_read, +	.unlocked_ioctl = fsl_hv_ioctl, +	.compat_ioctl = fsl_hv_ioctl, +}; + +static struct miscdevice fsl_hv_misc_dev = { +	MISC_DYNAMIC_MINOR, +	"fsl-hv", +	&fsl_hv_fops +}; + +static irqreturn_t fsl_hv_shutdown_isr(int irq, void *data) +{ +	orderly_poweroff(false); + +	return IRQ_HANDLED; +} + +/* + * Returns the handle of the parent of the given node + * + * The handle is the value of the 'hv-handle' property + */ +static int get_parent_handle(struct device_node *np) +{ +	struct device_node *parent; +	const uint32_t *prop; +	uint32_t handle; +	int len; + +	parent = of_get_parent(np); +	if (!parent) +		/* It's not really possible for this to fail */ +		return -ENODEV; + +	/* +	 * The proper name for the handle property is "hv-handle", but some +	 * older versions of the hypervisor used "reg". +	 */ +	prop = of_get_property(parent, "hv-handle", &len); +	if (!prop) +		prop = of_get_property(parent, "reg", &len); + +	if (!prop || (len != sizeof(uint32_t))) { +		/* This can happen only if the node is malformed */ +		of_node_put(parent); +		return -ENODEV; +	} + +	handle = be32_to_cpup(prop); +	of_node_put(parent); + +	return handle; +} + +/* + * Register a callback for failover events + * + * This function is called by device drivers to register their callback + * functions for fail-over events. + */ +int fsl_hv_failover_register(struct notifier_block *nb) +{ +	return blocking_notifier_chain_register(&failover_subscribers, nb); +} +EXPORT_SYMBOL(fsl_hv_failover_register); + +/* + * Unregister a callback for failover events + */ +int fsl_hv_failover_unregister(struct notifier_block *nb) +{ +	return blocking_notifier_chain_unregister(&failover_subscribers, nb); +} +EXPORT_SYMBOL(fsl_hv_failover_unregister); + +/* + * Return TRUE if we're running under FSL hypervisor + * + * This function checks to see if we're running under the Freescale + * hypervisor, and returns zero if we're not, or non-zero if we are. + * + * First, it checks if MSR[GS]==1, which means we're running under some + * hypervisor.  Then it checks if there is a hypervisor node in the device + * tree.  Currently, that means there needs to be a node in the root called + * "hypervisor" and which has a property named "fsl,hv-version". + */ +static int has_fsl_hypervisor(void) +{ +	struct device_node *node; +	int ret; + +	node = of_find_node_by_path("/hypervisor"); +	if (!node) +		return 0; + +	ret = of_find_property(node, "fsl,hv-version", NULL) != NULL; + +	of_node_put(node); + +	return ret; +} + +/* + * Freescale hypervisor management driver init + * + * This function is called when this module is loaded. + * + * Register ourselves as a miscellaneous driver.  This will register the + * fops structure and create the right sysfs entries for udev. + */ +static int __init fsl_hypervisor_init(void) +{ +	struct device_node *np; +	struct doorbell_isr *dbisr, *n; +	int ret; + +	pr_info("Freescale hypervisor management driver\n"); + +	if (!has_fsl_hypervisor()) { +		pr_info("fsl-hv: no hypervisor found\n"); +		return -ENODEV; +	} + +	ret = misc_register(&fsl_hv_misc_dev); +	if (ret) { +		pr_err("fsl-hv: cannot register device\n"); +		return ret; +	} + +	INIT_LIST_HEAD(&db_list); +	INIT_LIST_HEAD(&isr_list); + +	for_each_compatible_node(np, NULL, "epapr,hv-receive-doorbell") { +		unsigned int irq; +		const uint32_t *handle; + +		handle = of_get_property(np, "interrupts", NULL); +		irq = irq_of_parse_and_map(np, 0); +		if (!handle || (irq == NO_IRQ)) { +			pr_err("fsl-hv: no 'interrupts' property in %s node\n", +				np->full_name); +			continue; +		} + +		dbisr = kzalloc(sizeof(*dbisr), GFP_KERNEL); +		if (!dbisr) +			goto out_of_memory; + +		dbisr->irq = irq; +		dbisr->doorbell = be32_to_cpup(handle); + +		if (of_device_is_compatible(np, "fsl,hv-shutdown-doorbell")) { +			/* The shutdown doorbell gets its own ISR */ +			ret = request_irq(irq, fsl_hv_shutdown_isr, 0, +					  np->name, NULL); +		} else if (of_device_is_compatible(np, +			"fsl,hv-state-change-doorbell")) { +			/* +			 * The state change doorbell triggers a notification if +			 * the state of the managed partition changes to +			 * "stopped". We need a separate interrupt handler for +			 * that, and we also need to know the handle of the +			 * target partition, not just the handle of the +			 * doorbell. +			 */ +			dbisr->partition = ret = get_parent_handle(np); +			if (ret < 0) { +				pr_err("fsl-hv: node %s has missing or " +				       "malformed parent\n", np->full_name); +				kfree(dbisr); +				continue; +			} +			ret = request_threaded_irq(irq, fsl_hv_state_change_isr, +						   fsl_hv_state_change_thread, +						   0, np->name, dbisr); +		} else +			ret = request_irq(irq, fsl_hv_isr, 0, np->name, dbisr); + +		if (ret < 0) { +			pr_err("fsl-hv: could not request irq %u for node %s\n", +			       irq, np->full_name); +			kfree(dbisr); +			continue; +		} + +		list_add(&dbisr->list, &isr_list); + +		pr_info("fsl-hv: registered handler for doorbell %u\n", +			dbisr->doorbell); +	} + +	return 0; + +out_of_memory: +	list_for_each_entry_safe(dbisr, n, &isr_list, list) { +		free_irq(dbisr->irq, dbisr); +		list_del(&dbisr->list); +		kfree(dbisr); +	} + +	misc_deregister(&fsl_hv_misc_dev); + +	return -ENOMEM; +} + +/* + * Freescale hypervisor management driver termination + * + * This function is called when this driver is unloaded. + */ +static void __exit fsl_hypervisor_exit(void) +{ +	struct doorbell_isr *dbisr, *n; + +	list_for_each_entry_safe(dbisr, n, &isr_list, list) { +		free_irq(dbisr->irq, dbisr); +		list_del(&dbisr->list); +		kfree(dbisr); +	} + +	misc_deregister(&fsl_hv_misc_dev); +} + +module_init(fsl_hypervisor_init); +module_exit(fsl_hypervisor_exit); + +MODULE_AUTHOR("Timur Tabi <timur@freescale.com>"); +MODULE_DESCRIPTION("Freescale hypervisor management driver"); +MODULE_LICENSE("GPL v2");  | 
