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). To accomplish this, add a new parameter for airq_iv_create which allows passing an existing vector to be used instead of allocating a new one. The caller is responsible for ensuring the vector is pinned in memory as well as for unpinning the memory when the vector is no longer needed.
A subsequent patch will use this new parameter for zPCI interpretation. Reviewed-by: Pierre Morel <[email protected]> Reviewed-by: Claudio Imbrenda <[email protected]> Acked-by: Cornelia Huck <[email protected]> Signed-off-by: Matthew Rosato <[email protected]> --- 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 cc4c8d7c8f5c..0d0a02a9fbbf 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, NULL); if (!zdev->aibv) return -ENOMEM; @@ -419,7 +419,7 @@ 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, NULL); if (!zpci_sbv) return -ENOMEM; @@ -441,7 +441,7 @@ 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), NULL); if (!zpci_ibv[cpu]) return -ENOMEM; } @@ -458,7 +458,7 @@ 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, NULL); 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..410498d693f8 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, NULL); if (!info->aiv) { kfree(info); return NULL; -- 2.27.0 _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
