Revert "KVM: irqfd"

This reverts commit 302471ec2b5b6f74eba06973fb85e4584d20ef1e.

6 files changed, 1 insertions, 256 deletions

diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index 01e3c61f749a..bee9512cd60d 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -2,7 +2,7 @@
 EXTRA_CFLAGS += -Ivirt/kvm -Iarch/x86/kvm
 
 kvm-y			+= $(addprefix ../../../virt/kvm/, kvm_main.o ioapic.o \
-				coalesced_mmio.o irq_comm.o eventfd.o)
+				coalesced_mmio.o irq_comm.o)
 kvm-$(CONFIG_KVM_TRACE)	+= $(addprefix ../../../virt/kvm/, kvm_trace.o)
 kvm-$(CONFIG_IOMMU_API)	+= $(addprefix ../../../virt/kvm/, iommu.o)
 
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 98c24347a38a..7978d32fa11f 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1084,7 +1084,6 @@ int kvm_dev_ioctl_check_extension(long ext)
 	case KVM_CAP_REINJECT_CONTROL:
 	case KVM_CAP_IRQ_INJECT_STATUS:
 	case KVM_CAP_ASSIGN_DEV_IRQ:
-	case KVM_CAP_IRQFD:
 		r = 1;
 		break;
 	case KVM_CAP_COALESCED_MMIO:
diff --git a/include/linux/kvm.h b/include/linux/kvm.h
index 8f53f24e5274..7b17141c47c9 100644
--- a/include/linux/kvm.h
+++ b/include/linux/kvm.h
@@ -418,7 +418,6 @@ struct kvm_trace_rec {
 #ifdef __KVM_HAVE_MCE
 #define KVM_CAP_MCE 31
 #endif
-#define KVM_CAP_IRQFD 32
 
 #ifdef KVM_CAP_IRQ_ROUTING
 
@@ -471,15 +470,6 @@ struct kvm_x86_mce {
 };
 #endif
 
-#define KVM_IRQFD_FLAG_DEASSIGN (1 << 0)
-
-struct kvm_irqfd {
-	__u32 fd;
-	__u32 gsi;
-	__u32 flags;
-	__u8  pad[20];
-};
-
 /*
  * ioctls for VM fds
  */
@@ -524,7 +514,6 @@ struct kvm_irqfd {
 #define KVM_ASSIGN_SET_MSIX_ENTRY \
 			_IOW(KVMIO, 0x74, struct kvm_assigned_msix_entry)
 #define KVM_DEASSIGN_DEV_IRQ       _IOW(KVMIO, 0x75, struct kvm_assigned_irq)
-#define KVM_IRQFD                  _IOW(KVMIO, 0x76, struct kvm_irqfd)
 
 /*
  * ioctls for vcpu fds
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 3b6caf511422..8f410d32b0c7 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -134,7 +134,6 @@ struct kvm {
 	struct list_head vm_list;
 	struct kvm_io_bus mmio_bus;
 	struct kvm_io_bus pio_bus;
-	struct list_head irqfds;
 	struct kvm_vm_stat stat;
 	struct kvm_arch arch;
 	atomic_t users_count;
@@ -529,7 +528,4 @@ static inline void kvm_free_irq_routing(struct kvm *kvm) {}
 
 #endif
 
-int kvm_irqfd(struct kvm *kvm, int fd, int gsi, int flags);
-void kvm_irqfd_release(struct kvm *kvm);
-
 #endif
diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c
deleted file mode 100644
index 72a282e39c3f..000000000000
--- a/virt/kvm/eventfd.c
+++ /dev/null
@@ -1,228 +0,0 @@
-/*
- * kvm eventfd support - use eventfd objects to signal various KVM events
- *
- * Copyright 2009 Novell.  All Rights Reserved.
- *
- * Author:
- *	Gregory Haskins <ghaskins@novell.com>
- *
- * This file is free software; you can redistribute it and/or modify
- * it under the terms of version 2 of the GNU General Public License
- * as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
- */
-
-#include <linux/kvm_host.h>
-#include <linux/workqueue.h>
-#include <linux/syscalls.h>
-#include <linux/wait.h>
-#include <linux/poll.h>
-#include <linux/file.h>
-#include <linux/list.h>
-
-/*
- * --------------------------------------------------------------------
- * irqfd: Allows an fd to be used to inject an interrupt to the guest
- *
- * Credit goes to Avi Kivity for the original idea.
- * --------------------------------------------------------------------
- */
-struct _irqfd {
-	struct kvm               *kvm;
-	int                       gsi;
-	struct file              *file;
-	struct list_head          list;
-	poll_table                pt;
-	wait_queue_head_t        *wqh;
-	wait_queue_t              wait;
-	struct work_struct        work;
-};
-
-static void
-irqfd_inject(struct work_struct *work)
-{
-	struct _irqfd *irqfd = container_of(work, struct _irqfd, work);
-	struct kvm *kvm = irqfd->kvm;
-
-	mutex_lock(&kvm->lock);
-	kvm_set_irq(kvm, KVM_USERSPACE_IRQ_SOURCE_ID, irqfd->gsi, 1);
-	kvm_set_irq(kvm, KVM_USERSPACE_IRQ_SOURCE_ID, irqfd->gsi, 0);
-	mutex_unlock(&kvm->lock);
-}
-
-static int
-irqfd_wakeup(wait_queue_t *wait, unsigned mode, int sync, void *key)
-{
-	struct _irqfd *irqfd = container_of(wait, struct _irqfd, wait);
-
-	/*
-	 * The wake_up is called with interrupts disabled.  Therefore we need
-	 * to defer the IRQ injection until later since we need to acquire the
-	 * kvm->lock to do so.
-	 */
-	schedule_work(&irqfd->work);
-
-	return 0;
-}
-
-static void
-irqfd_ptable_queue_proc(struct file *file, wait_queue_head_t *wqh,
-			poll_table *pt)
-{
-	struct _irqfd *irqfd = container_of(pt, struct _irqfd, pt);
-
-	irqfd->wqh = wqh;
-	add_wait_queue(wqh, &irqfd->wait);
-}
-
-static int
-kvm_assign_irqfd(struct kvm *kvm, int fd, int gsi)
-{
-	struct _irqfd *irqfd;
-	struct file *file = NULL;
-	int ret;
-
-	irqfd = kzalloc(sizeof(*irqfd), GFP_KERNEL);
-	if (!irqfd)
-		return -ENOMEM;
-
-	irqfd->kvm = kvm;
-	irqfd->gsi = gsi;
-	INIT_LIST_HEAD(&irqfd->list);
-	INIT_WORK(&irqfd->work, irqfd_inject);
-
-	/*
-	 * Embed the file* lifetime in the irqfd.
-	 */
-	file = fget(fd);
-	if (IS_ERR(file)) {
-		ret = PTR_ERR(file);
-		goto fail;
-	}
-
-	/*
-	 * Install our own custom wake-up handling so we are notified via
-	 * a callback whenever someone signals the underlying eventfd
-	 */
-	init_waitqueue_func_entry(&irqfd->wait, irqfd_wakeup);
-	init_poll_funcptr(&irqfd->pt, irqfd_ptable_queue_proc);
-
-	ret = file->f_op->poll(file, &irqfd->pt);
-	if (ret < 0)
-		goto fail;
-
-	irqfd->file = file;
-
-	mutex_lock(&kvm->lock);
-	list_add_tail(&irqfd->list, &kvm->irqfds);
-	mutex_unlock(&kvm->lock);
-
-	return 0;
-
-fail:
-	if (irqfd->wqh)
-		remove_wait_queue(irqfd->wqh, &irqfd->wait);
-
-	if (file && !IS_ERR(file))
-		fput(file);
-
-	kfree(irqfd);
-	return ret;
-}
-
-static void
-irqfd_release(struct _irqfd *irqfd)
-{
-	/*
-	 * The ordering is important.  We must remove ourselves from the wqh
-	 * first to ensure no more event callbacks are issued, and then flush
-	 * any previously scheduled work prior to freeing the memory
-	 */
-	remove_wait_queue(irqfd->wqh, &irqfd->wait);
-
-	flush_work(&irqfd->work);
-
-	fput(irqfd->file);
-	kfree(irqfd);
-}
-
-static struct _irqfd *
-irqfd_remove(struct kvm *kvm, struct file *file, int gsi)
-{
-	struct _irqfd *irqfd;
-
-	mutex_lock(&kvm->lock);
-
-	/*
-	 * linear search isn't brilliant, but this should be an infrequent
-	 * slow-path operation, and the list should not grow very large
-	 */
-	list_for_each_entry(irqfd, &kvm->irqfds, list) {
-		if (irqfd->file != file || irqfd->gsi != gsi)
-			continue;
-
-		list_del(&irqfd->list);
-		mutex_unlock(&kvm->lock);
-
-		return irqfd;
-	}
-
-	mutex_unlock(&kvm->lock);
-
-	return NULL;
-}
-
-static int
-kvm_deassign_irqfd(struct kvm *kvm, int fd, int gsi)
-{
-	struct _irqfd *irqfd;
-	struct file *file;
-	int count = 0;
-
-	file = fget(fd);
-	if (IS_ERR(file))
-		return PTR_ERR(file);
-
-	while ((irqfd = irqfd_remove(kvm, file, gsi))) {
-		/*
-		 * We remove the item from the list under the lock, but we
-		 * free it outside the lock to avoid deadlocking with the
-		 * flush_work and the work_item taking the lock
-		 */
-		irqfd_release(irqfd);
-		count++;
-	}
-
-	fput(file);
-
-	return count ? count : -ENOENT;
-}
-
-int
-kvm_irqfd(struct kvm *kvm, int fd, int gsi, int flags)
-{
-	if (flags & KVM_IRQFD_FLAG_DEASSIGN)
-		return kvm_deassign_irqfd(kvm, fd, gsi);
-
-	return kvm_assign_irqfd(kvm, fd, gsi);
-}
-
-void
-kvm_irqfd_release(struct kvm *kvm)
-{
-	struct _irqfd *irqfd, *tmp;
-
-	/* don't bother with the lock..we are shutting down */
-	list_for_each_entry_safe(irqfd, tmp, &kvm->irqfds, list) {
-		list_del(&irqfd->list);
-		irqfd_release(irqfd);
-	}
-}
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index b58837d61ce6..bebfe59f4c76 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -983,7 +983,6 @@ static struct kvm *kvm_create_vm(void)
 	atomic_inc(&kvm->mm->mm_count);
 	spin_lock_init(&kvm->mmu_lock);
 	kvm_io_bus_init(&kvm->pio_bus);
-	INIT_LIST_HEAD(&kvm->irqfds);
 	mutex_init(&kvm->lock);
 	kvm_io_bus_init(&kvm->mmio_bus);
 	init_rwsem(&kvm->slots_lock);
@@ -1035,7 +1034,6 @@ static void kvm_destroy_vm(struct kvm *kvm)
 	spin_lock(&kvm_lock);
 	list_del(&kvm->vm_list);
 	spin_unlock(&kvm_lock);
-	kvm_irqfd_release(kvm);
 	kvm_free_irq_routing(kvm);
 	kvm_io_bus_destroy(&kvm->pio_bus);
 	kvm_io_bus_destroy(&kvm->mmio_bus);
@@ -2212,15 +2210,6 @@ static long kvm_vm_ioctl(struct file *filp,
 	}
 #endif
 #endif /* KVM_CAP_IRQ_ROUTING */
-	case KVM_IRQFD: {
-		struct kvm_irqfd data;
-
-		r = -EFAULT;
-		if (copy_from_user(&data, argp, sizeof data))
-			goto out;
-		r = kvm_irqfd(kvm, data.fd, data.gsi, data.flags);
-		break;
-	}
 	default:
 		r = kvm_arch_vm_ioctl(filp, ioctl, arg);
 	}