diff options
| author | Sebastian Ott <sebott@linux.vnet.ibm.com> | 2017-12-01 18:47:32 +0100 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2017-12-13 10:51:33 +0100 |
| commit | a5f1005517534aeb1fac20180badfbf0896c183c (patch) | |
| tree | 24c450680c2879193ff6d12f71411c3a479c4919 /arch/s390/pci/pci_dma.c | |
| parent | d39a01eff9af1045f6e30ff9db40310517c4b45f (diff) | |
s390/pci: handle insufficient resources during dma tlb flush
In a virtualized setup lazy flushing can lead to the hypervisor
running out of resources when lots of guest pages need to be
pinned. In this situation simply trigger a global flush to give
the hypervisor a chance to free some of these resources.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/pci/pci_dma.c')
| -rw-r--r-- | arch/s390/pci/pci_dma.c | 21 |
1 files changed, 19 insertions, 2 deletions
diff --git a/arch/s390/pci/pci_dma.c b/arch/s390/pci/pci_dma.c index f7aa5a77827e..2d15d84c20ed 100644 --- a/arch/s390/pci/pci_dma.c +++ b/arch/s390/pci/pci_dma.c @@ -181,6 +181,9 @@ out_unlock: static int __dma_purge_tlb(struct zpci_dev *zdev, dma_addr_t dma_addr, size_t size, int flags) { + unsigned long irqflags; + int ret; + /* * With zdev->tlb_refresh == 0, rpcit is not required to establish new * translations when previously invalid translation-table entries are @@ -196,8 +199,22 @@ static int __dma_purge_tlb(struct zpci_dev *zdev, dma_addr_t dma_addr, return 0; } - return zpci_refresh_trans((u64) zdev->fh << 32, dma_addr, - PAGE_ALIGN(size)); + ret = zpci_refresh_trans((u64) zdev->fh << 32, dma_addr, + PAGE_ALIGN(size)); + if (ret == -ENOMEM && !s390_iommu_strict) { + /* enable the hypervisor to free some resources */ + if (zpci_refresh_global(zdev)) + goto out; + + spin_lock_irqsave(&zdev->iommu_bitmap_lock, irqflags); + bitmap_andnot(zdev->iommu_bitmap, zdev->iommu_bitmap, + zdev->lazy_bitmap, zdev->iommu_pages); + bitmap_zero(zdev->lazy_bitmap, zdev->iommu_pages); + spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, irqflags); + ret = 0; + } +out: + return ret; } static int dma_update_trans(struct zpci_dev *zdev, unsigned long pa, |