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| author | Zhen Lei <thunder.leizhen@huawei.com> | 2018-09-20 17:10:23 +0100 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2018-10-01 13:01:32 +0100 |
| commit | 68a6efe86f6a16e25556a2aff40efad41097b486 (patch) | |
| tree | d4422500a10c32ef7e40cc37598a92f6dd472222 /drivers/iommu | |
| parent | 2da274cdf998a1c12afa6b5975db2df1df01edf1 (diff) | |
| download | linux-68a6efe86f6a16e25556a2aff40efad41097b486.tar.bz2 | |
iommu: Add "iommu.strict" command line option
Add a generic command line option to enable lazy unmapping via IOVA
flush queues, which will initally be suuported by iommu-dma. This echoes
the semantics of "intel_iommu=strict" (albeit with the opposite default
value), but in the driver-agnostic fashion of "iommu.passthrough".
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
[rm: move handling out of SMMUv3 driver, clean up documentation]
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
[will: dropped broken printk when parsing command-line option]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'drivers/iommu')
| -rw-r--r-- | drivers/iommu/iommu.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 8c15c5980299..2b6dad2aa9f1 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -41,6 +41,7 @@ static unsigned int iommu_def_domain_type = IOMMU_DOMAIN_IDENTITY; #else static unsigned int iommu_def_domain_type = IOMMU_DOMAIN_DMA; #endif +static bool iommu_dma_strict __read_mostly = true; struct iommu_callback_data { const struct iommu_ops *ops; @@ -131,6 +132,12 @@ static int __init iommu_set_def_domain_type(char *str) } early_param("iommu.passthrough", iommu_set_def_domain_type); +static int __init iommu_dma_setup(char *str) +{ + return kstrtobool(str, &iommu_dma_strict); +} +early_param("iommu.strict", iommu_dma_setup); + static ssize_t iommu_group_attr_show(struct kobject *kobj, struct attribute *__attr, char *buf) { @@ -1072,6 +1079,13 @@ struct iommu_group *iommu_group_get_for_dev(struct device *dev) group->default_domain = dom; if (!group->domain) group->domain = dom; + + if (dom && !iommu_dma_strict) { + int attr = 1; + iommu_domain_set_attr(dom, + DOMAIN_ATTR_DMA_USE_FLUSH_QUEUE, + &attr); + } } ret = iommu_group_add_device(group, dev); |