diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-08-07 08:41:00 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-08-07 08:41:00 -0700 |
commit | ebb067d2f4e2db59b076f9c9cba0375a8ad1e07c (patch) | |
tree | 8d4fc065ab0fd45fca9483acfff93d4a6c74e981 /arch/s390/pci/pci_dma.c | |
parent | 33caee39925b887a99a2400dc5c980097c3573f9 (diff) | |
parent | 36e7fdaa1a04fcf65b864232e1af56a51c7814d6 (diff) |
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:
"Mostly cleanups and bug-fixes, with two exceptions.
The first is lazy flushing of I/O-TLBs for PCI to improve performance,
the second is software dirty bits in the pmd for the madvise-free
implementation"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (24 commits)
s390/locking: Reenable optimistic spinning
s390/mm: implement dirty bits for large segment table entries
KVM: s390/mm: Fix page table locking vs. split pmd lock
s390/dasd: fix camel case
s390/3215: fix hanging console issue
s390/irq: improve displayed interrupt order in /proc/interrupts
s390/seccomp: fix error return for filtered system calls
s390/pci: introduce lazy IOTLB flushing for DMA unmap
dasd: fix error recovery for alias devices during format
dasd: fix list_del corruption during format
dasd: fix unresponsive device during format
dasd: use aliases for formatted devices during format
s390/pci: fix kmsg component
s390/kdump: Return NOTIFY_OK for all actions other than MEM_GOING_OFFLINE
s390/watchdog: Fix module name in Kconfig help text
s390/dasd: replace seq_printf by seq_puts
s390/dasd: replace pr_warning by pr_warn
s390/dasd: Move EXPORT_SYMBOL after function/variable
s390/dasd: remove unnecessary null test before debugfs_remove
s390/zfcp: use qdio buffer helpers
...
Diffstat (limited to 'arch/s390/pci/pci_dma.c')
-rw-r--r-- | arch/s390/pci/pci_dma.c | 50 |
1 files changed, 36 insertions, 14 deletions
diff --git a/arch/s390/pci/pci_dma.c b/arch/s390/pci/pci_dma.c index f91c03119804..4cbb29a4d615 100644 --- a/arch/s390/pci/pci_dma.c +++ b/arch/s390/pci/pci_dma.c @@ -16,6 +16,13 @@ static struct kmem_cache *dma_region_table_cache; static struct kmem_cache *dma_page_table_cache; +static int s390_iommu_strict; + +static int zpci_refresh_global(struct zpci_dev *zdev) +{ + return zpci_refresh_trans((u64) zdev->fh << 32, zdev->start_dma, + zdev->iommu_pages * PAGE_SIZE); +} static unsigned long *dma_alloc_cpu_table(void) { @@ -155,18 +162,15 @@ static int dma_update_trans(struct zpci_dev *zdev, unsigned long pa, } /* - * rpcit is not required to establish new translations when previously - * invalid translation-table entries are validated, however it is - * required when altering previously valid entries. + * With zdev->tlb_refresh == 0, rpcit is not required to establish new + * translations when previously invalid translation-table entries are + * validated. With lazy unmap, it also is skipped for previously valid + * entries, but a global rpcit is then required before any address can + * be re-used, i.e. after each iommu bitmap wrap-around. */ if (!zdev->tlb_refresh && - ((flags & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID)) - /* - * TODO: also need to check that the old entry is indeed INVALID - * and not only for one page but for the whole range... - * -> now we WARN_ON in that case but with lazy unmap that - * needs to be redone! - */ + (!s390_iommu_strict || + ((flags & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID))) goto no_refresh; rc = zpci_refresh_trans((u64) zdev->fh << 32, start_dma_addr, @@ -220,16 +224,21 @@ static unsigned long __dma_alloc_iommu(struct zpci_dev *zdev, static unsigned long dma_alloc_iommu(struct zpci_dev *zdev, int size) { unsigned long offset, flags; + int wrap = 0; spin_lock_irqsave(&zdev->iommu_bitmap_lock, flags); offset = __dma_alloc_iommu(zdev, zdev->next_bit, size); - if (offset == -1) + if (offset == -1) { + /* wrap-around */ offset = __dma_alloc_iommu(zdev, 0, size); + wrap = 1; + } if (offset != -1) { zdev->next_bit = offset + size; - if (zdev->next_bit >= zdev->iommu_pages) - zdev->next_bit = 0; + if (!zdev->tlb_refresh && !s390_iommu_strict && wrap) + /* global flush after wrap-around with lazy unmap */ + zpci_refresh_global(zdev); } spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, flags); return offset; @@ -243,7 +252,11 @@ static void dma_free_iommu(struct zpci_dev *zdev, unsigned long offset, int size if (!zdev->iommu_bitmap) goto out; bitmap_clear(zdev->iommu_bitmap, offset, size); - if (offset >= zdev->next_bit) + /* + * Lazy flush for unmap: need to move next_bit to avoid address re-use + * until wrap-around. + */ + if (!s390_iommu_strict && offset >= zdev->next_bit) zdev->next_bit = offset + size; out: spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, flags); @@ -504,3 +517,12 @@ struct dma_map_ops s390_dma_ops = { /* dma_supported is unconditionally true without a callback */ }; EXPORT_SYMBOL_GPL(s390_dma_ops); + +static int __init s390_iommu_setup(char *str) +{ + if (!strncmp(str, "strict", 6)) + s390_iommu_strict = 1; + return 0; +} + +__setup("s390_iommu=", s390_iommu_setup); |