On Wed, 12 Jun 2019 13:12:32 +0200 Halil Pasic <pasic@xxxxxxxxxxxxx> wrote: > Protected virtualization guests have to use shared pages for airq > notifier bit vectors, because 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: Halil Pasic <pasic@xxxxxxxxxxxxx> > Reviewed-by: Sebastian Ott <sebott@xxxxxxxxxxxxx> > --- > arch/s390/include/asm/airq.h | 2 ++ > drivers/s390/cio/airq.c | 37 ++++++++++++++++++++++-------------- > drivers/s390/cio/cio.h | 2 ++ > drivers/s390/cio/css.c | 1 + > 4 files changed, 28 insertions(+), 14 deletions(-) > (...) > /** > * 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) I still think squashing this into the same if statement is a bit ugly, but not really an issue. > 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; > } (...) > diff --git a/drivers/s390/cio/cio.h b/drivers/s390/cio/cio.h > index 06a91743335a..4d6c7d16416e 100644 > --- a/drivers/s390/cio/cio.h > +++ b/drivers/s390/cio/cio.h > @@ -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); > diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c > index e0f19f1e82a0..1b867c941b86 100644 > --- a/drivers/s390/cio/css.c > +++ b/drivers/s390/cio/css.c > @@ -1184,6 +1184,7 @@ static int __init css_bus_init(void) > ret = cio_dma_pool_init(); > if (ret) > goto out_unregister_pmn; > + airq_init(); Ignoring the return code here does not really hurt right now, but we probably want to change that if we want to consider failures in css initialization to be fatal. > css_init_done = 1; > > /* Enable default isc for I/O subchannels. */ On the whole, not really anything that needs changes right now, so have a Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx>