diff options
| author | Will Deacon <will.deacon@arm.com> | 2016-02-17 17:41:57 +0000 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2016-02-18 15:02:44 +0000 |
| commit | bc7f2ce0a7b54ba7703f81995fe434f0926424d2 (patch) | |
| tree | 1e27c323f9c3becd069a36abb54ff2fb2ca7d93b /drivers/iommu/arm-smmu.c | |
| parent | 25a1c96cd22c949b50d6f0269c23e1c5cb55e5a5 (diff) | |
iommu/arm-smmu: Don't fail device attach if already attached to a domain
The ARM SMMU attach_dev implementations returns -EEXIST if the device
being attached is already attached to a domain. This doesn't play nicely
with the default domain, resulting in splats such as:
WARNING: at drivers/iommu/iommu.c:1257
Modules linked in:
CPU: 3 PID: 1939 Comm: virtio-net-tx Tainted: G S 4.5.0-rc4+ #1
Hardware name: FVP Base (DT)
task: ffffffc87a9d0000 ti: ffffffc07a278000 task.ti: ffffffc07a278000
PC is at __iommu_detach_group+0x68/0xe8
LR is at __iommu_detach_group+0x48/0xe8
This patch fixes the problem by forcefully detaching the device from
its old domain, if present, when attaching to a new one. The unused
->detach_dev callback is also removed the iommu_ops structures.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'drivers/iommu/arm-smmu.c')
| -rw-r--r-- | drivers/iommu/arm-smmu.c | 33 |
1 files changed, 14 insertions, 19 deletions
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index 7012531abe62..f21332a15040 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -1131,6 +1131,16 @@ static void arm_smmu_domain_remove_master(struct arm_smmu_domain *smmu_domain, arm_smmu_master_free_smrs(smmu, cfg); } +static void arm_smmu_detach_dev(struct device *dev, + struct arm_smmu_master_cfg *cfg) +{ + struct iommu_domain *domain = dev->archdata.iommu; + struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); + + dev->archdata.iommu = NULL; + arm_smmu_domain_remove_master(smmu_domain, cfg); +} + static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) { int ret; @@ -1144,11 +1154,6 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) return -ENXIO; } - if (dev->archdata.iommu) { - dev_err(dev, "already attached to IOMMU domain\n"); - return -EEXIST; - } - /* Ensure that the domain is finalised */ ret = arm_smmu_init_domain_context(domain, smmu); if (IS_ERR_VALUE(ret)) @@ -1170,25 +1175,16 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) if (!cfg) return -ENODEV; + /* Detach the dev from its current domain */ + if (dev->archdata.iommu) + arm_smmu_detach_dev(dev, cfg); + ret = arm_smmu_domain_add_master(smmu_domain, cfg); if (!ret) dev->archdata.iommu = domain; return ret; } -static void arm_smmu_detach_dev(struct iommu_domain *domain, struct device *dev) -{ - struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); - struct arm_smmu_master_cfg *cfg; - - cfg = find_smmu_master_cfg(dev); - if (!cfg) - return; - - dev->archdata.iommu = NULL; - arm_smmu_domain_remove_master(smmu_domain, cfg); -} - static int arm_smmu_map(struct iommu_domain *domain, unsigned long iova, phys_addr_t paddr, size_t size, int prot) { @@ -1464,7 +1460,6 @@ static struct iommu_ops arm_smmu_ops = { .domain_alloc = arm_smmu_domain_alloc, .domain_free = arm_smmu_domain_free, .attach_dev = arm_smmu_attach_dev, - .detach_dev = arm_smmu_detach_dev, .map = arm_smmu_map, .unmap = arm_smmu_unmap, .map_sg = default_iommu_map_sg, |