Commit 4fe5e199 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'for-linus-4.4-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip 

Pull xen bug fixes from David Vrabel:

 - Fix gntdev and numa balancing.

 - Fix x86 boot crash due to unallocated legacy irq descs.

 - Fix overflow in evtchn device when > 1024 event channels.

* tag 'for-linus-4.4-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/evtchn: dynamically grow pending event channel ring
  xen/events: Always allocate legacy interrupts on PV guests
  xen/gntdev: Grant maps should not be subject to NUMA balancing
parents 02a5fec1 86200154

arch/arm/include/asm/irq.h

+5 −0
Original line number Diff line number Diff line
@@ -40,6 +40,11 @@ extern void arch_trigger_all_cpu_backtrace(bool); 
#define arch_trigger_all_cpu_backtrace(x) arch_trigger_all_cpu_backtrace(x)

#endif



static inline int nr_legacy_irqs(void)

{

	return NR_IRQS_LEGACY;

}



#endif



#endif

arch/arm64/include/asm/irq.h

+5 −0
Original line number Diff line number Diff line
@@ -7,4 +7,9 @@ struct pt_regs; 


extern void set_handle_irq(void (*handle_irq)(struct pt_regs *));



static inline int nr_legacy_irqs(void)

{

	return 0;

}



#endif

drivers/xen/events/events_base.c

+3 −2
Original line number Diff line number Diff line
@@ -39,6 +39,7 @@ 
#include <asm/irq.h>

#include <asm/idle.h>

#include <asm/io_apic.h>

#include <asm/i8259.h>

#include <asm/xen/pci.h>

#endif

#include <asm/sync_bitops.h>
@@ -420,7 +421,7 @@ static int __must_check xen_allocate_irq_gsi(unsigned gsi) 
		return xen_allocate_irq_dynamic();



	/* Legacy IRQ descriptors are already allocated by the arch. */

	if (gsi < NR_IRQS_LEGACY)

	if (gsi < nr_legacy_irqs())

		irq = gsi;

	else

		irq = irq_alloc_desc_at(gsi, -1);
@@ -446,7 +447,7 @@ static void xen_free_irq(unsigned irq) 
	kfree(info);



	/* Legacy IRQ descriptors are managed by the arch. */

	if (irq < NR_IRQS_LEGACY)

	if (irq < nr_legacy_irqs())

		return;



	irq_free_desc(irq);

drivers/xen/evtchn.c

+107 −16
Original line number Diff line number Diff line
@@ -49,6 +49,8 @@ 
#include <linux/init.h>

#include <linux/mutex.h>

#include <linux/cpu.h>

#include <linux/mm.h>

#include <linux/vmalloc.h>



#include <xen/xen.h>

#include <xen/events.h>
@@ -58,10 +60,10 @@ 
struct per_user_data {

	struct mutex bind_mutex; /* serialize bind/unbind operations */

	struct rb_root evtchns;

	unsigned int nr_evtchns;



	/* Notification ring, accessed via /dev/xen/evtchn. */

#define EVTCHN_RING_SIZE     (PAGE_SIZE / sizeof(evtchn_port_t))

#define EVTCHN_RING_MASK(_i) ((_i)&(EVTCHN_RING_SIZE-1))

	unsigned int ring_size;

	evtchn_port_t *ring;

	unsigned int ring_cons, ring_prod, ring_overflow;

	struct mutex ring_cons_mutex; /* protect against concurrent readers */
@@ -80,10 +82,41 @@ struct user_evtchn { 
	bool enabled;

};



static evtchn_port_t *evtchn_alloc_ring(unsigned int size)

{

	evtchn_port_t *ring;

	size_t s = size * sizeof(*ring);



	ring = kmalloc(s, GFP_KERNEL);

	if (!ring)

		ring = vmalloc(s);



	return ring;

}



static void evtchn_free_ring(evtchn_port_t *ring)

{

	kvfree(ring);

}



static unsigned int evtchn_ring_offset(struct per_user_data *u,

				       unsigned int idx)

{

	return idx & (u->ring_size - 1);

}



static evtchn_port_t *evtchn_ring_entry(struct per_user_data *u,

					unsigned int idx)

{

	return u->ring + evtchn_ring_offset(u, idx);

}



static int add_evtchn(struct per_user_data *u, struct user_evtchn *evtchn)

{

	struct rb_node **new = &(u->evtchns.rb_node), *parent = NULL;



	u->nr_evtchns++;



	while (*new) {

		struct user_evtchn *this;
@@ -107,6 +140,7 @@ static int add_evtchn(struct per_user_data *u, struct user_evtchn *evtchn) 


static void del_evtchn(struct per_user_data *u, struct user_evtchn *evtchn)

{

	u->nr_evtchns--;

	rb_erase(&evtchn->node, &u->evtchns);

	kfree(evtchn);

}
@@ -144,8 +178,8 @@ static irqreturn_t evtchn_interrupt(int irq, void *data) 


	spin_lock(&u->ring_prod_lock);



	if ((u->ring_prod - u->ring_cons) < EVTCHN_RING_SIZE) {

		u->ring[EVTCHN_RING_MASK(u->ring_prod)] = evtchn->port;

	if ((u->ring_prod - u->ring_cons) < u->ring_size) {

		*evtchn_ring_entry(u, u->ring_prod) = evtchn->port;

		wmb(); /* Ensure ring contents visible */

		if (u->ring_cons == u->ring_prod++) {

			wake_up_interruptible(&u->evtchn_wait);
@@ -200,10 +234,10 @@ static ssize_t evtchn_read(struct file *file, char __user *buf, 
	}



	/* Byte lengths of two chunks. Chunk split (if any) is at ring wrap. */

	if (((c ^ p) & EVTCHN_RING_SIZE) != 0) {

		bytes1 = (EVTCHN_RING_SIZE - EVTCHN_RING_MASK(c)) *

	if (((c ^ p) & u->ring_size) != 0) {

		bytes1 = (u->ring_size - evtchn_ring_offset(u, c)) *

			sizeof(evtchn_port_t);

		bytes2 = EVTCHN_RING_MASK(p) * sizeof(evtchn_port_t);

		bytes2 = evtchn_ring_offset(u, p) * sizeof(evtchn_port_t);

	} else {

		bytes1 = (p - c) * sizeof(evtchn_port_t);

		bytes2 = 0;
@@ -219,7 +253,7 @@ static ssize_t evtchn_read(struct file *file, char __user *buf, 


	rc = -EFAULT;

	rmb(); /* Ensure that we see the port before we copy it. */

	if (copy_to_user(buf, &u->ring[EVTCHN_RING_MASK(c)], bytes1) ||

	if (copy_to_user(buf, evtchn_ring_entry(u, c), bytes1) ||

	    ((bytes2 != 0) &&

	     copy_to_user(&buf[bytes1], &u->ring[0], bytes2)))

		goto unlock_out;
@@ -278,6 +312,66 @@ static ssize_t evtchn_write(struct file *file, const char __user *buf, 
	return rc;

}



static int evtchn_resize_ring(struct per_user_data *u)

{

	unsigned int new_size;

	evtchn_port_t *new_ring, *old_ring;

	unsigned int p, c;



	/*

	 * Ensure the ring is large enough to capture all possible

	 * events. i.e., one free slot for each bound event.

	 */

	if (u->nr_evtchns <= u->ring_size)

		return 0;



	if (u->ring_size == 0)

		new_size = 64;

	else

		new_size = 2 * u->ring_size;



	new_ring = evtchn_alloc_ring(new_size);

	if (!new_ring)

		return -ENOMEM;



	old_ring = u->ring;



	/*

	 * Access to the ring contents is serialized by either the

	 * prod /or/ cons lock so take both when resizing.

	 */

	mutex_lock(&u->ring_cons_mutex);

	spin_lock_irq(&u->ring_prod_lock);



	/*

	 * Copy the old ring contents to the new ring.

	 *

	 * If the ring contents crosses the end of the current ring,

	 * it needs to be copied in two chunks.

	 *

	 * +---------+    +------------------+

	 * |34567  12| -> |       1234567    |

	 * +-----p-c-+    +------------------+

	 */

	p = evtchn_ring_offset(u, u->ring_prod);

	c = evtchn_ring_offset(u, u->ring_cons);

	if (p < c) {

		memcpy(new_ring + c, u->ring + c, (u->ring_size - c) * sizeof(*u->ring));

		memcpy(new_ring + u->ring_size, u->ring, p * sizeof(*u->ring));

	} else

		memcpy(new_ring + c, u->ring + c, (p - c) * sizeof(*u->ring));



	u->ring = new_ring;

	u->ring_size = new_size;



	spin_unlock_irq(&u->ring_prod_lock);

	mutex_unlock(&u->ring_cons_mutex);



	evtchn_free_ring(old_ring);



	return 0;

}



static int evtchn_bind_to_user(struct per_user_data *u, int port)

{

	struct user_evtchn *evtchn;
@@ -305,6 +399,10 @@ static int evtchn_bind_to_user(struct per_user_data *u, int port) 
	if (rc < 0)

		goto err;



	rc = evtchn_resize_ring(u);

	if (rc < 0)

		goto err;



	rc = bind_evtchn_to_irqhandler(port, evtchn_interrupt, 0,

				       u->name, evtchn);

	if (rc < 0)
@@ -503,13 +601,6 @@ static int evtchn_open(struct inode *inode, struct file *filp) 


	init_waitqueue_head(&u->evtchn_wait);



	u->ring = (evtchn_port_t *)__get_free_page(GFP_KERNEL);

	if (u->ring == NULL) {

		kfree(u->name);

		kfree(u);

		return -ENOMEM;

	}



	mutex_init(&u->bind_mutex);

	mutex_init(&u->ring_cons_mutex);

	spin_lock_init(&u->ring_prod_lock);
@@ -532,7 +623,7 @@ static int evtchn_release(struct inode *inode, struct file *filp) 
		evtchn_unbind_from_user(u, evtchn);

	}



	free_page((unsigned long)u->ring);

	evtchn_free_ring(u->ring);

	kfree(u->name);

	kfree(u);

drivers/xen/gntdev.c

+1 −1
Original line number Diff line number Diff line
@@ -804,7 +804,7 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma) 


	vma->vm_ops = &gntdev_vmops;



	vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;

	vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP | VM_IO;



	if (use_ptemod)

		vma->vm_flags |= VM_DONTCOPY;

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