diff mbox series

[06/32] s390/airq: allow for airq structure that uses an input vector

Message ID 20211207205743.150299-7-mjrosato@linux.ibm.com (mailing list archive)
State New, archived
Headers show
Series KVM: s390: enable zPCI for interpretive execution | expand

Commit Message

Matthew Rosato Dec. 7, 2021, 8:57 p.m. UTC 
When doing device passthrough where interrupts are being forwarded
from host to guest, we wish to use a pinned section of guest memory
as the vector (the same memory used by the guest as the vector).

Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
---
 arch/s390/include/asm/airq.h     |  4 +++-
 arch/s390/pci/pci_irq.c          |  8 ++++----
 drivers/s390/cio/airq.c          | 10 +++++++---
 drivers/s390/virtio/virtio_ccw.c |  2 +-
 4 files changed, 15 insertions(+), 9 deletions(-)

Comments

Thomas Huth Dec. 8, 2021, 10:04 a.m. UTC | #1 
On 07/12/2021 21.57, Matthew Rosato wrote:
> When doing device passthrough where interrupts are being forwarded
> from host to guest, we wish to use a pinned section of guest memory
> as the vector (the same memory used by the guest as the vector).
> 
> Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
> ---
[...]
> diff --git a/arch/s390/pci/pci_irq.c b/arch/s390/pci/pci_irq.c
> index 880bcd73f11a..dfd4f3276a6d 100644
> --- a/arch/s390/pci/pci_irq.c
> +++ b/arch/s390/pci/pci_irq.c
[...]
> @@ -443,7 +443,7 @@ static int __init zpci_directed_irq_init(void)
>   		zpci_ibv[cpu] = airq_iv_create(cache_line_size() * BITS_PER_BYTE,
>   					       AIRQ_IV_DATA |
>   					       AIRQ_IV_CACHELINE |
> -					       (!cpu ? AIRQ_IV_ALLOC : 0));
> +					(!cpu ? AIRQ_IV_ALLOC : 0), 0);

Nit: Indentation changed

> diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c
> index 52c376d15978..ff84f45587be 100644
> --- a/drivers/s390/virtio/virtio_ccw.c
> +++ b/drivers/s390/virtio/virtio_ccw.c
> @@ -241,7 +241,7 @@ static struct airq_info *new_airq_info(int index)
>   		return NULL;
>   	rwlock_init(&info->lock);
>   	info->aiv = airq_iv_create(VIRTIO_IV_BITS, AIRQ_IV_ALLOC | AIRQ_IV_PTR
> -				   | AIRQ_IV_CACHELINE);
> +				| AIRQ_IV_CACHELINE, 0);

dito

>   	if (!info->aiv) {
>   		kfree(info);
>   		return NULL;
> 

  Thomas
Christian Borntraeger Dec. 8, 2021, 12:59 p.m. UTC | #2 
Am 07.12.21 um 21:57 schrieb Matthew Rosato:
> When doing device passthrough where interrupts are being forwarded
> from host to guest, we wish to use a pinned section of guest memory
> as the vector (the same memory used by the guest as the vector).
> 
> Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
> ---
>   arch/s390/include/asm/airq.h     |  4 +++-
>   arch/s390/pci/pci_irq.c          |  8 ++++----
>   drivers/s390/cio/airq.c          | 10 +++++++---
>   drivers/s390/virtio/virtio_ccw.c |  2 +-
>   4 files changed, 15 insertions(+), 9 deletions(-)
> 
> diff --git a/arch/s390/include/asm/airq.h b/arch/s390/include/asm/airq.h
> index 7918a7d09028..e82e5626e139 100644
> --- a/arch/s390/include/asm/airq.h
> +++ b/arch/s390/include/asm/airq.h
> @@ -47,8 +47,10 @@ struct airq_iv {
>   #define AIRQ_IV_PTR		4	/* Allocate the ptr array */
>   #define AIRQ_IV_DATA		8	/* Allocate the data array */
>   #define AIRQ_IV_CACHELINE	16	/* Cacheline alignment for the vector */
> +#define AIRQ_IV_GUESTVEC	32	/* Vector is a pinned guest page */
>   
> -struct airq_iv *airq_iv_create(unsigned long bits, unsigned long flags);
> +struct airq_iv *airq_iv_create(unsigned long bits, unsigned long flags,
> +			       unsigned long *vec);
>   void airq_iv_release(struct airq_iv *iv);
>   unsigned long airq_iv_alloc(struct airq_iv *iv, unsigned long num);
>   void airq_iv_free(struct airq_iv *iv, unsigned long bit, unsigned long num);
> diff --git a/arch/s390/pci/pci_irq.c b/arch/s390/pci/pci_irq.c
> index 880bcd73f11a..dfd4f3276a6d 100644
> --- a/arch/s390/pci/pci_irq.c
> +++ b/arch/s390/pci/pci_irq.c
> @@ -296,7 +296,7 @@ int arch_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
>   		zdev->aisb = bit;
>   
>   		/* Create adapter interrupt vector */
> -		zdev->aibv = airq_iv_create(msi_vecs, AIRQ_IV_DATA | AIRQ_IV_BITLOCK);
> +		zdev->aibv = airq_iv_create(msi_vecs, AIRQ_IV_DATA | AIRQ_IV_BITLOCK, 0);
>   		if (!zdev->aibv)
>   			return -ENOMEM;
>   
> @@ -421,7 +421,7 @@ static int __init zpci_directed_irq_init(void)
>   	union zpci_sic_iib iib = {{0}};
>   	unsigned int cpu;
>   
> -	zpci_sbv = airq_iv_create(num_possible_cpus(), 0);
> +	zpci_sbv = airq_iv_create(num_possible_cpus(), 0, 0);

For a pointer use NULL? Also in other places. With the indentation fix this looks sane.
diff mbox series

Patch

diff --git a/arch/s390/include/asm/airq.h b/arch/s390/include/asm/airq.h
index 7918a7d09028..e82e5626e139 100644
--- a/arch/s390/include/asm/airq.h
+++ b/arch/s390/include/asm/airq.h
@@ -47,8 +47,10 @@  struct airq_iv {
 #define AIRQ_IV_PTR		4	/* Allocate the ptr array */
 #define AIRQ_IV_DATA		8	/* Allocate the data array */
 #define AIRQ_IV_CACHELINE	16	/* Cacheline alignment for the vector */
+#define AIRQ_IV_GUESTVEC	32	/* Vector is a pinned guest page */
 
-struct airq_iv *airq_iv_create(unsigned long bits, unsigned long flags);
+struct airq_iv *airq_iv_create(unsigned long bits, unsigned long flags,
+			       unsigned long *vec);
 void airq_iv_release(struct airq_iv *iv);
 unsigned long airq_iv_alloc(struct airq_iv *iv, unsigned long num);
 void airq_iv_free(struct airq_iv *iv, unsigned long bit, unsigned long num);
diff --git a/arch/s390/pci/pci_irq.c b/arch/s390/pci/pci_irq.c
index 880bcd73f11a..dfd4f3276a6d 100644
--- a/arch/s390/pci/pci_irq.c
+++ b/arch/s390/pci/pci_irq.c
@@ -296,7 +296,7 @@  int arch_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
 		zdev->aisb = bit;
 
 		/* Create adapter interrupt vector */
-		zdev->aibv = airq_iv_create(msi_vecs, AIRQ_IV_DATA | AIRQ_IV_BITLOCK);
+		zdev->aibv = airq_iv_create(msi_vecs, AIRQ_IV_DATA | AIRQ_IV_BITLOCK, 0);
 		if (!zdev->aibv)
 			return -ENOMEM;
 
@@ -421,7 +421,7 @@  static int __init zpci_directed_irq_init(void)
 	union zpci_sic_iib iib = {{0}};
 	unsigned int cpu;
 
-	zpci_sbv = airq_iv_create(num_possible_cpus(), 0);
+	zpci_sbv = airq_iv_create(num_possible_cpus(), 0, 0);
 	if (!zpci_sbv)
 		return -ENOMEM;
 
@@ -443,7 +443,7 @@  static int __init zpci_directed_irq_init(void)
 		zpci_ibv[cpu] = airq_iv_create(cache_line_size() * BITS_PER_BYTE,
 					       AIRQ_IV_DATA |
 					       AIRQ_IV_CACHELINE |
-					       (!cpu ? AIRQ_IV_ALLOC : 0));
+					(!cpu ? AIRQ_IV_ALLOC : 0), 0);
 		if (!zpci_ibv[cpu])
 			return -ENOMEM;
 	}
@@ -460,7 +460,7 @@  static int __init zpci_floating_irq_init(void)
 	if (!zpci_ibv)
 		return -ENOMEM;
 
-	zpci_sbv = airq_iv_create(ZPCI_NR_DEVICES, AIRQ_IV_ALLOC);
+	zpci_sbv = airq_iv_create(ZPCI_NR_DEVICES, AIRQ_IV_ALLOC, 0);
 	if (!zpci_sbv)
 		goto out_free;
 
diff --git a/drivers/s390/cio/airq.c b/drivers/s390/cio/airq.c
index 2f2226786319..375a58b1c838 100644
--- a/drivers/s390/cio/airq.c
+++ b/drivers/s390/cio/airq.c
@@ -122,10 +122,12 @@  static inline unsigned long iv_size(unsigned long bits)
  * airq_iv_create - create an interrupt vector
  * @bits: number of bits in the interrupt vector
  * @flags: allocation flags
+ * @vec: pointer to pinned guest memory if AIRQ_IV_GUESTVEC
  *
  * Returns a pointer to an interrupt vector structure
  */
-struct airq_iv *airq_iv_create(unsigned long bits, unsigned long flags)
+struct airq_iv *airq_iv_create(unsigned long bits, unsigned long flags,
+			       unsigned long *vec)
 {
 	struct airq_iv *iv;
 	unsigned long size;
@@ -146,6 +148,8 @@  struct airq_iv *airq_iv_create(unsigned long bits, unsigned long flags)
 					     &iv->vector_dma);
 		if (!iv->vector)
 			goto out_free;
+	} else if (flags & AIRQ_IV_GUESTVEC) {
+		iv->vector = vec;
 	} else {
 		iv->vector = cio_dma_zalloc(size);
 		if (!iv->vector)
@@ -185,7 +189,7 @@  struct airq_iv *airq_iv_create(unsigned long bits, unsigned long flags)
 	kfree(iv->avail);
 	if (iv->flags & AIRQ_IV_CACHELINE && iv->vector)
 		dma_pool_free(airq_iv_cache, iv->vector, iv->vector_dma);
-	else
+	else if (!(iv->flags & AIRQ_IV_GUESTVEC))
 		cio_dma_free(iv->vector, size);
 	kfree(iv);
 out:
@@ -204,7 +208,7 @@  void airq_iv_release(struct airq_iv *iv)
 	kfree(iv->bitlock);
 	if (iv->flags & AIRQ_IV_CACHELINE)
 		dma_pool_free(airq_iv_cache, iv->vector, iv->vector_dma);
-	else
+	else if (!(iv->flags & AIRQ_IV_GUESTVEC))
 		cio_dma_free(iv->vector, iv_size(iv->bits));
 	kfree(iv->avail);
 	kfree(iv);
diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c
index 52c376d15978..ff84f45587be 100644
--- a/drivers/s390/virtio/virtio_ccw.c
+++ b/drivers/s390/virtio/virtio_ccw.c
@@ -241,7 +241,7 @@  static struct airq_info *new_airq_info(int index)
 		return NULL;
 	rwlock_init(&info->lock);
 	info->aiv = airq_iv_create(VIRTIO_IV_BITS, AIRQ_IV_ALLOC | AIRQ_IV_PTR
-				   | AIRQ_IV_CACHELINE);
+				| AIRQ_IV_CACHELINE, 0);
 	if (!info->aiv) {
 		kfree(info);
 		return NULL;