The fault handler will need to find a process given its PASID. This is the reason we have an IDR for storing processes, so hook it up.
Signed-off-by: Jean-Philippe Brucker <[email protected]> --- drivers/iommu/iommu-process.c | 35 +++++++++++++++++++++++++++++++++++ include/linux/iommu.h | 12 ++++++++++++ 2 files changed, 47 insertions(+) diff --git a/drivers/iommu/iommu-process.c b/drivers/iommu/iommu-process.c index 61ca0bd707c0..8f4c98632d58 100644 --- a/drivers/iommu/iommu-process.c +++ b/drivers/iommu/iommu-process.c @@ -145,6 +145,41 @@ static void iommu_process_put_locked(struct iommu_process *process) kref_put(&process->kref, iommu_process_release); } +/** + * iommu_process_put - Put reference to process, freeing it if necessary. + */ +void iommu_process_put(struct iommu_process *process) +{ + spin_lock(&iommu_process_lock); + iommu_process_put_locked(process); + spin_unlock(&iommu_process_lock); +} +EXPORT_SYMBOL_GPL(iommu_process_put); + +/** + * iommu_process_find - Find process associated to the given PASID + * + * Returns the IOMMU process corresponding to this PASID, or NULL if not found. + * A reference to the iommu_process is kept, and must be released with + * iommu_process_put. + */ +struct iommu_process *iommu_process_find(int pasid) +{ + struct iommu_process *process; + + spin_lock(&iommu_process_lock); + process = idr_find(&iommu_process_idr, pasid); + if (process) { + if (!iommu_process_get_locked(process)) + /* kref is 0, process is defunct */ + process = NULL; + } + spin_unlock(&iommu_process_lock); + + return process; +} +EXPORT_SYMBOL_GPL(iommu_process_find); + static int iommu_process_attach(struct iommu_domain *domain, struct device *dev, struct iommu_process *process) { diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 8d74f9058f30..e9528fcacab1 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -733,12 +733,24 @@ const struct iommu_ops *iommu_ops_from_fwnode(struct fwnode_handle *fwnode) extern void iommu_set_process_exit_handler(struct device *dev, iommu_process_exit_handler_t cb, void *token); +extern struct iommu_process *iommu_process_find(int pasid); +extern void iommu_process_put(struct iommu_process *process); + #else /* CONFIG_IOMMU_PROCESS */ static inline void iommu_set_process_exit_handler(struct device *dev, iommu_process_exit_handler_t cb, void *token) { } + +static inline struct iommu_process *iommu_process_find(int pasid) +{ + return NULL; +} + +static inline void iommu_process_put(struct iommu_process *process) +{ +} #endif /* CONFIG_IOMMU_PROCESS */ #endif /* __LINUX_IOMMU_H */ -- 2.13.3 _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
