diff options
Diffstat (limited to 'drivers/xen')
-rw-r--r-- | drivers/xen/Makefile | 5 | ||||
-rw-r--r-- | drivers/xen/evtchn.c | 100 | ||||
-rw-r--r-- | drivers/xen/xenfs/privcmd.c | 13 | ||||
-rw-r--r-- | drivers/xen/xenfs/super.c | 50 |
4 files changed, 94 insertions, 74 deletions
diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile index eb8a78d..533a199 100644 --- a/drivers/xen/Makefile +++ b/drivers/xen/Makefile @@ -8,9 +8,12 @@ obj-$(CONFIG_BLOCK) += biomerge.o obj-$(CONFIG_HOTPLUG_CPU) += cpu_hotplug.o obj-$(CONFIG_XEN_XENCOMM) += xencomm.o obj-$(CONFIG_XEN_BALLOON) += balloon.o -obj-$(CONFIG_XEN_DEV_EVTCHN) += evtchn.o +obj-$(CONFIG_XEN_DEV_EVTCHN) += xen-evtchn.o obj-$(CONFIG_XENFS) += xenfs/ obj-$(CONFIG_XEN_SYS_HYPERVISOR) += sys-hypervisor.o obj-$(CONFIG_XEN_PLATFORM_PCI) += platform-pci.o obj-$(CONFIG_SWIOTLB_XEN) += swiotlb-xen.o obj-$(CONFIG_XEN_DOM0) += pci.o + +xen-evtchn-y := evtchn.o + diff --git a/drivers/xen/evtchn.c b/drivers/xen/evtchn.c index fec6ba3..ef11daf 100644 --- a/drivers/xen/evtchn.c +++ b/drivers/xen/evtchn.c @@ -69,20 +69,51 @@ struct per_user_data { const char *name; }; -/* Who's bound to each port? */ -static struct per_user_data *port_user[NR_EVENT_CHANNELS]; +/* + * Who's bound to each port? This is logically an array of struct + * per_user_data *, but we encode the current enabled-state in bit 0. + */ +static unsigned long *port_user; static DEFINE_SPINLOCK(port_user_lock); /* protects port_user[] and ring_prod */ -irqreturn_t evtchn_interrupt(int irq, void *data) +static inline struct per_user_data *get_port_user(unsigned port) +{ + return (struct per_user_data *)(port_user[port] & ~1); +} + +static inline void set_port_user(unsigned port, struct per_user_data *u) +{ + port_user[port] = (unsigned long)u; +} + +static inline bool get_port_enabled(unsigned port) +{ + return port_user[port] & 1; +} + +static inline void set_port_enabled(unsigned port, bool enabled) +{ + if (enabled) + port_user[port] |= 1; + else + port_user[port] &= ~1; +} + +static irqreturn_t evtchn_interrupt(int irq, void *data) { unsigned int port = (unsigned long)data; struct per_user_data *u; spin_lock(&port_user_lock); - u = port_user[port]; + u = get_port_user(port); + + WARN(!get_port_enabled(port), + "Interrupt for port %d, but apparently not enabled; per-user %p\n", + port, u); disable_irq_nosync(irq); + set_port_enabled(port, false); if ((u->ring_prod - u->ring_cons) < EVTCHN_RING_SIZE) { u->ring[EVTCHN_RING_MASK(u->ring_prod)] = port; @@ -92,9 +123,8 @@ irqreturn_t evtchn_interrupt(int irq, void *data) kill_fasync(&u->evtchn_async_queue, SIGIO, POLL_IN); } - } else { + } else u->ring_overflow = 1; - } spin_unlock(&port_user_lock); @@ -198,9 +228,18 @@ static ssize_t evtchn_write(struct file *file, const char __user *buf, goto out; spin_lock_irq(&port_user_lock); - for (i = 0; i < (count/sizeof(evtchn_port_t)); i++) - if ((kbuf[i] < NR_EVENT_CHANNELS) && (port_user[kbuf[i]] == u)) - enable_irq(irq_from_evtchn(kbuf[i])); + + for (i = 0; i < (count/sizeof(evtchn_port_t)); i++) { + unsigned port = kbuf[i]; + + if (port < NR_EVENT_CHANNELS && + get_port_user(port) == u && + !get_port_enabled(port)) { + set_port_enabled(port, true); + enable_irq(irq_from_evtchn(port)); + } + } + spin_unlock_irq(&port_user_lock); rc = count; @@ -222,8 +261,9 @@ static int evtchn_bind_to_user(struct per_user_data *u, int port) * interrupt handler yet, and our caller has already * serialized bind operations.) */ - BUG_ON(port_user[port] != NULL); - port_user[port] = u; + BUG_ON(get_port_user(port) != NULL); + set_port_user(port, u); + set_port_enabled(port, true); /* start enabled */ rc = bind_evtchn_to_irqhandler(port, evtchn_interrupt, IRQF_DISABLED, u->name, (void *)(unsigned long)port); @@ -239,10 +279,7 @@ static void evtchn_unbind_from_user(struct per_user_data *u, int port) unbind_from_irqhandler(irq, (void *)(unsigned long)port); - /* make sure we unbind the irq handler before clearing the port */ - barrier(); - - port_user[port] = NULL; + set_port_user(port, NULL); } static long evtchn_ioctl(struct file *file, @@ -333,15 +370,17 @@ static long evtchn_ioctl(struct file *file, spin_lock_irq(&port_user_lock); rc = -ENOTCONN; - if (port_user[unbind.port] != u) { + if (get_port_user(unbind.port) != u) { spin_unlock_irq(&port_user_lock); break; } - evtchn_unbind_from_user(u, unbind.port); + disable_irq(irq_from_evtchn(unbind.port)); spin_unlock_irq(&port_user_lock); + evtchn_unbind_from_user(u, unbind.port); + rc = 0; break; } @@ -355,7 +394,7 @@ static long evtchn_ioctl(struct file *file, if (notify.port >= NR_EVENT_CHANNELS) { rc = -EINVAL; - } else if (port_user[notify.port] != u) { + } else if (get_port_user(notify.port) != u) { rc = -ENOTCONN; } else { notify_remote_via_evtchn(notify.port); @@ -431,7 +470,7 @@ static int evtchn_open(struct inode *inode, struct file *filp) filp->private_data = u; - return 0; + return nonseekable_open(inode, filp);; } static int evtchn_release(struct inode *inode, struct file *filp) @@ -444,14 +483,21 @@ static int evtchn_release(struct inode *inode, struct file *filp) free_page((unsigned long)u->ring); for (i = 0; i < NR_EVENT_CHANNELS; i++) { - if (port_user[i] != u) + if (get_port_user(i) != u) continue; - evtchn_unbind_from_user(port_user[i], i); + disable_irq(irq_from_evtchn(i)); } spin_unlock_irq(&port_user_lock); + for (i = 0; i < NR_EVENT_CHANNELS; i++) { + if (get_port_user(i) != u) + continue; + + evtchn_unbind_from_user(get_port_user(i), i); + } + kfree(u->name); kfree(u); @@ -467,12 +513,12 @@ static const struct file_operations evtchn_fops = { .fasync = evtchn_fasync, .open = evtchn_open, .release = evtchn_release, - .llseek = noop_llseek, + .llseek = no_llseek, }; static struct miscdevice evtchn_miscdev = { .minor = MISC_DYNAMIC_MINOR, - .name = "evtchn", + .name = "xen/evtchn", .fops = &evtchn_fops, }; static int __init evtchn_init(void) @@ -482,8 +528,11 @@ static int __init evtchn_init(void) if (!xen_domain()) return -ENODEV; + port_user = kcalloc(NR_EVENT_CHANNELS, sizeof(*port_user), GFP_KERNEL); + if (port_user == NULL) + return -ENOMEM; + spin_lock_init(&port_user_lock); - memset(port_user, 0, sizeof(port_user)); /* Create '/dev/misc/evtchn'. */ err = misc_register(&evtchn_miscdev); @@ -499,6 +548,9 @@ static int __init evtchn_init(void) static void __exit evtchn_cleanup(void) { + kfree(port_user); + port_user = NULL; + misc_deregister(&evtchn_miscdev); } diff --git a/drivers/xen/xenfs/privcmd.c b/drivers/xen/xenfs/privcmd.c index f80be7f..88474d4 100644 --- a/drivers/xen/xenfs/privcmd.c +++ b/drivers/xen/xenfs/privcmd.c @@ -266,9 +266,7 @@ static int mmap_return_errors(void *data, void *state) xen_pfn_t *mfnp = data; struct mmap_batch_state *st = state; - put_user(*mfnp, st->user++); - - return 0; + return put_user(*mfnp, st->user++); } static struct vm_operations_struct privcmd_vm_ops; @@ -323,10 +321,8 @@ static long privcmd_ioctl_mmap_batch(void __user *udata) up_write(&mm->mmap_sem); if (state.err > 0) { - ret = 0; - state.user = m.arr; - traverse_pages(m.num, sizeof(xen_pfn_t), + ret = traverse_pages(m.num, sizeof(xen_pfn_t), &pagelist, mmap_return_errors, &state); } @@ -384,8 +380,9 @@ static int privcmd_mmap(struct file *file, struct vm_area_struct *vma) if (xen_feature(XENFEAT_auto_translated_physmap)) return -ENOSYS; - /* DONTCOPY is essential for Xen as copy_page_range is broken. */ - vma->vm_flags |= VM_RESERVED | VM_IO | VM_DONTCOPY; + /* DONTCOPY is essential for Xen because copy_page_range doesn't know + * how to recreate these mappings */ + vma->vm_flags |= VM_RESERVED | VM_IO | VM_DONTCOPY | VM_PFNMAP; vma->vm_ops = &privcmd_vm_ops; vma->vm_private_data = NULL; diff --git a/drivers/xen/xenfs/super.c b/drivers/xen/xenfs/super.c index d6662b7..1aa3897 100644 --- a/drivers/xen/xenfs/super.c +++ b/drivers/xen/xenfs/super.c @@ -12,8 +12,6 @@ #include <linux/module.h> #include <linux/fs.h> #include <linux/magic.h> -#include <linux/mm.h> -#include <linux/backing-dev.h> #include <xen/xen.h> @@ -24,28 +22,12 @@ MODULE_DESCRIPTION("Xen filesystem"); MODULE_LICENSE("GPL"); -static int xenfs_set_page_dirty(struct page *page) -{ - return !TestSetPageDirty(page); -} - -static const struct address_space_operations xenfs_aops = { - .set_page_dirty = xenfs_set_page_dirty, -}; - -static struct backing_dev_info xenfs_backing_dev_info = { - .ra_pages = 0, /* No readahead */ - .capabilities = BDI_CAP_NO_ACCT_AND_WRITEBACK, -}; - static struct inode *xenfs_make_inode(struct super_block *sb, int mode) { struct inode *ret = new_inode(sb); if (ret) { ret->i_mode = mode; - ret->i_mapping->a_ops = &xenfs_aops; - ret->i_mapping->backing_dev_info = &xenfs_backing_dev_info; ret->i_uid = ret->i_gid = 0; ret->i_blocks = 0; ret->i_atime = ret->i_mtime = ret->i_ctime = CURRENT_TIME; @@ -121,41 +103,27 @@ static int xenfs_fill_super(struct super_block *sb, void *data, int silent) return rc; } -static int xenfs_get_sb(struct file_system_type *fs_type, - int flags, const char *dev_name, - void *data, struct vfsmount *mnt) +static struct dentry *xenfs_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, + void *data) { - return get_sb_single(fs_type, flags, data, xenfs_fill_super, mnt); + return mount_single(fs_type, flags, data, xenfs_fill_super); } static struct file_system_type xenfs_type = { .owner = THIS_MODULE, .name = "xenfs", - .get_sb = xenfs_get_sb, + .mount = xenfs_mount, .kill_sb = kill_litter_super, }; static int __init xenfs_init(void) { - int err; - if (!xen_domain()) { - printk(KERN_INFO "xenfs: not registering filesystem on non-xen platform\n"); - return 0; - } - - err = register_filesystem(&xenfs_type); - if (err) { - printk(KERN_ERR "xenfs: Unable to register filesystem!\n"); - goto out; - } - - err = bdi_init(&xenfs_backing_dev_info); - if (err) - unregister_filesystem(&xenfs_type); - - out: + if (xen_domain()) + return register_filesystem(&xenfs_type); - return err; + printk(KERN_INFO "XENFS: not registering filesystem on non-xen platform\n"); + return 0; } static void __exit xenfs_exit(void) |