diff options
| author | Matthew Rosato <mjrosato@linux.ibm.com> | 2022-06-06 16:33:10 -0400 |
|---|---|---|
| committer | Christian Borntraeger <borntraeger@linux.ibm.com> | 2022-07-11 09:54:15 +0200 |
| commit | 932b646727f9df312980d175e339248cdf7812f0 (patch) | |
| tree | 4c76c26e938597df4d219bc9f9f3c5e625c962c2 /drivers/s390/cio/airq.c | |
| parent | d2197485a1883c60d044146b1ee69aac654c55e8 (diff) | |
| download | linux-932b646727f9df312980d175e339248cdf7812f0.tar.bz2 | |
s390/airq: allow for airq structure that uses an input vector
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: Thomas Huth <thuth@redhat.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20220606203325.110625-7-mjrosato@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Diffstat (limited to 'drivers/s390/cio/airq.c')
| -rw-r--r-- | drivers/s390/cio/airq.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/drivers/s390/cio/airq.c b/drivers/s390/cio/airq.c index 230eb5b5b64e..34967e67249e 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 @@ out_free: 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); |