diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/Kconfig | 2 | ||||
| -rw-r--r-- | drivers/Makefile | 3 | ||||
| -rw-r--r-- | drivers/virt/Kconfig | 32 | ||||
| -rw-r--r-- | drivers/virt/Makefile | 5 | ||||
| -rw-r--r-- | drivers/virt/fsl_hypervisor.c | 937 |
5 files changed, 979 insertions, 0 deletions
diff --git a/drivers/Kconfig b/drivers/Kconfig index 3bb154d8c8c..3c1d4a59a86 100644 --- a/drivers/Kconfig +++ b/drivers/Kconfig @@ -126,4 +126,6 @@ source "drivers/hwspinlock/Kconfig" source "drivers/clocksource/Kconfig" +source "drivers/virt/Kconfig" + endmenu diff --git a/drivers/Makefile b/drivers/Makefile index 09f3232bcdc..cd546ebab9a 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -122,3 +122,6 @@ obj-y += ieee802154/ obj-y += clk/ obj-$(CONFIG_HWSPINLOCK) += hwspinlock/ + +# Virtualization drivers +obj-$(CONFIG_VIRT_DRIVERS) += virt/ diff --git a/drivers/virt/Kconfig b/drivers/virt/Kconfig new file mode 100644 index 00000000000..2dcdbc9364d --- /dev/null +++ b/drivers/virt/Kconfig @@ -0,0 +1,32 @@ +# +# Virtualization support drivers +# + +menuconfig VIRT_DRIVERS + bool "Virtualization drivers" + ---help--- + Say Y here to get to see options for device drivers that support + virtualization environments. + + If you say N, all options in this submenu will be skipped and disabled. + +if VIRT_DRIVERS + +config FSL_HV_MANAGER + tristate "Freescale hypervisor management driver" + depends on FSL_SOC + help + 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. + +endif diff --git a/drivers/virt/Makefile b/drivers/virt/Makefile new file mode 100644 index 00000000000..c47f04dd343 --- /dev/null +++ b/drivers/virt/Makefile @@ -0,0 +1,5 @@ +# +# Makefile for drivers that support virtualization +# + +obj-$(CONFIG_FSL_HV_MANAGER) += fsl_hypervisor.o diff --git a/drivers/virt/fsl_hypervisor.c b/drivers/virt/fsl_hypervisor.c new file mode 100644 index 00000000000..1d3b8ebb314 --- /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/reboot.h> +#include <linux/uaccess.h> +#include <linux/notifier.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, +}; + +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; + + if (!(mfmsr() & MSR_GS)) + return 0; + + 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"); |