Commit b50623e5 authored by Halil Pasic's avatar Halil Pasic Committed by Heiko Carstens
Browse files

s390/airq: use DMA memory for adapter interrupts 



Protected virtualization guests have to use shared pages for airq
notifier bit vectors, because the hypervisor needs to write these bits.

Let us make sure we allocate DMA memory for the notifier bit vectors by
replacing the kmem_cache with a dma_cache and kalloc() with
cio_dma_zalloc().

Signed-off-by: default avatarHalil Pasic <pasic@linux.ibm.com>
Reviewed-by: default avatarSebastian Ott <sebott@linux.ibm.com>
Reviewed-by: default avatarMichael Mueller <mimu@linux.ibm.com>
Tested-by: default avatarMichael Mueller <mimu@linux.ibm.com>
Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
parent 37db8985

arch/s390/include/asm/airq.h

+2 −0
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ 
#define _ASM_S390_AIRQ_H



#include <linux/bit_spinlock.h>

#include <linux/dma-mapping.h>



struct airq_struct {

	struct hlist_node list;		/* Handler queueing. */
@@ -29,6 +30,7 @@ void unregister_adapter_interrupt(struct airq_struct *airq); 
/* Adapter interrupt bit vector */

struct airq_iv {

	unsigned long *vector;	/* Adapter interrupt bit vector */

	dma_addr_t vector_dma; /* Adapter interrupt bit vector dma */

	unsigned long *avail;	/* Allocation bit mask for the bit vector */

	unsigned long *bitlock;	/* Lock bit mask for the bit vector */

	unsigned long *ptr;	/* Pointer associated with each bit */

drivers/s390/cio/airq.c

+23 −14
Original line number Diff line number Diff line
@@ -16,9 +16,11 @@ 
#include <linux/mutex.h>

#include <linux/rculist.h>

#include <linux/slab.h>

#include <linux/dmapool.h>



#include <asm/airq.h>

#include <asm/isc.h>

#include <asm/cio.h>



#include "cio.h"

#include "cio_debug.h"
@@ -27,7 +29,7 @@ 
static DEFINE_SPINLOCK(airq_lists_lock);

static struct hlist_head airq_lists[MAX_ISC+1];



static struct kmem_cache *airq_iv_cache;

static struct dma_pool *airq_iv_cache;



/**

 * register_adapter_interrupt() - register adapter interrupt handler
@@ -115,6 +117,11 @@ void __init init_airq_interrupts(void) 
	setup_irq(THIN_INTERRUPT, &airq_interrupt);

}



static inline unsigned long iv_size(unsigned long bits)

{

	return BITS_TO_LONGS(bits) * sizeof(unsigned long);

}



/**

 * airq_iv_create - create an interrupt vector

 * @bits: number of bits in the interrupt vector
@@ -132,17 +139,19 @@ struct airq_iv *airq_iv_create(unsigned long bits, unsigned long flags) 
		goto out;

	iv->bits = bits;

	iv->flags = flags;

	size = BITS_TO_LONGS(bits) * sizeof(unsigned long);

	size = iv_size(bits);



	if (flags & AIRQ_IV_CACHELINE) {

		if ((cache_line_size() * BITS_PER_BYTE) < bits)

		if ((cache_line_size() * BITS_PER_BYTE) < bits

				|| !airq_iv_cache)

			goto out_free;



		iv->vector = kmem_cache_zalloc(airq_iv_cache, GFP_KERNEL);

		iv->vector = dma_pool_zalloc(airq_iv_cache, GFP_KERNEL,

					     &iv->vector_dma);

		if (!iv->vector)

			goto out_free;

	} else {

		iv->vector = kzalloc(size, GFP_KERNEL);

		iv->vector = cio_dma_zalloc(size);

		if (!iv->vector)

			goto out_free;

	}
@@ -178,10 +187,10 @@ out_free: 
	kfree(iv->ptr);

	kfree(iv->bitlock);

	kfree(iv->avail);

	if (iv->flags & AIRQ_IV_CACHELINE)

		kmem_cache_free(airq_iv_cache, iv->vector);

	if (iv->flags & AIRQ_IV_CACHELINE && iv->vector)

		dma_pool_free(airq_iv_cache, iv->vector, iv->vector_dma);

	else

		kfree(iv->vector);

		cio_dma_free(iv->vector, size);

	kfree(iv);

out:

	return NULL;
@@ -198,9 +207,9 @@ void airq_iv_release(struct airq_iv *iv) 
	kfree(iv->ptr);

	kfree(iv->bitlock);

	if (iv->flags & AIRQ_IV_CACHELINE)

		kmem_cache_free(airq_iv_cache, iv->vector);

		dma_pool_free(airq_iv_cache, iv->vector, iv->vector_dma);

	else

		kfree(iv->vector);

		cio_dma_free(iv->vector, iv_size(iv->bits));

	kfree(iv->avail);

	kfree(iv);

}
@@ -295,12 +304,12 @@ unsigned long airq_iv_scan(struct airq_iv *iv, unsigned long start, 
}

EXPORT_SYMBOL(airq_iv_scan);



static int __init airq_init(void)

int __init airq_init(void)

{

	airq_iv_cache = kmem_cache_create("airq_iv_cache", cache_line_size(),

					  cache_line_size(), 0, NULL);

	airq_iv_cache = dma_pool_create("airq_iv_cache", cio_get_dma_css_dev(),

					cache_line_size(),

					cache_line_size(), PAGE_SIZE);

	if (!airq_iv_cache)

		return -ENOMEM;

	return 0;

}
 
subsys_initcall(airq_init);

drivers/s390/cio/cio.h

+2 −0
Original line number Diff line number Diff line
@@ -135,6 +135,8 @@ extern int cio_commit_config(struct subchannel *sch); 
int cio_tm_start_key(struct subchannel *sch, struct tcw *tcw, u8 lpm, u8 key);

int cio_tm_intrg(struct subchannel *sch);



extern int __init airq_init(void);



/* Use with care. */

#ifdef CONFIG_CCW_CONSOLE

extern struct subchannel *cio_probe_console(void);

drivers/s390/cio/css.c

+1 −0
Original line number Diff line number Diff line
@@ -1184,6 +1184,7 @@ static int __init css_bus_init(void) 
	ret = cio_dma_pool_init();

	if (ret)

		goto out_unregister_pmn;

	airq_init();

	css_init_done = 1;



	/* Enable default isc for I/O subchannels. */

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