Many PCI passthru related hypercalls require partition id of the target guest. Guests are actually managed by MSHV driver and the partition id is only maintained there. Add a field in the partition struct in MSHV driver to save the tgid of the VMM process creating the partition, and add a function there to retrieve partition id if current process is a VMM process.
Signed-off-by: Mukesh R <[email protected]> --- drivers/hv/mshv_root.h | 1 + drivers/hv/mshv_root_main.c | 22 ++++++++++++++++++++++ include/asm-generic/mshyperv.h | 5 +++++ 3 files changed, 28 insertions(+) diff --git a/drivers/hv/mshv_root.h b/drivers/hv/mshv_root.h index 1f086dcb7aa1..a85c24dcc701 100644 --- a/drivers/hv/mshv_root.h +++ b/drivers/hv/mshv_root.h @@ -138,6 +138,7 @@ struct mshv_partition { struct mshv_girq_routing_table __rcu *pt_girq_tbl; u64 isolation_type; + pid_t pt_vmm_tgid; bool import_completed; bool pt_initialized; #if IS_ENABLED(CONFIG_DEBUG_FS) diff --git a/drivers/hv/mshv_root_main.c b/drivers/hv/mshv_root_main.c index bd1359eb58dd..02c107458be9 100644 --- a/drivers/hv/mshv_root_main.c +++ b/drivers/hv/mshv_root_main.c @@ -1908,6 +1908,27 @@ mshv_partition_release(struct inode *inode, struct file *filp) return 0; } +/* Given a process tgid, return partition id if it is a VMM process */ +u64 mshv_current_partid(void) +{ + struct mshv_partition *pt; + int i; + u64 ret_ptid = HV_PARTITION_ID_INVALID; + + rcu_read_lock(); + + hash_for_each_rcu(mshv_root.pt_htable, i, pt, pt_hnode) { + if (pt->pt_vmm_tgid == current->tgid) { + ret_ptid = pt->pt_id; + break; + } + } + + rcu_read_unlock(); + return ret_ptid; +} +EXPORT_SYMBOL_GPL(mshv_current_partid); + static int add_partition(struct mshv_partition *partition) { @@ -2073,6 +2094,7 @@ mshv_ioctl_create_partition(void __user *user_arg, struct device *module_dev) goto cleanup_irq_srcu; partition->pt_id = pt_id; + partition->pt_vmm_tgid = current->tgid; ret = add_partition(partition); if (ret) diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h index bf601d67cecb..e8cbc4e3f7ad 100644 --- a/include/asm-generic/mshyperv.h +++ b/include/asm-generic/mshyperv.h @@ -350,6 +350,7 @@ int hv_call_add_logical_proc(int node, u32 lp_index, u32 acpi_id); int hv_call_notify_all_processors_started(void); bool hv_lp_exists(u32 lp_index); int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u32 flags); +u64 mshv_current_partid(void); #else /* CONFIG_MSHV_ROOT */ static inline bool hv_root_partition(void) { return false; } @@ -380,6 +381,10 @@ static inline int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u3 { return -EOPNOTSUPP; } +static inline u64 mshv_current_partid(void) +{ + return HV_PARTITION_ID_INVALID; +} #endif /* CONFIG_MSHV_ROOT */ static inline int hv_deposit_memory(u64 partition_id, u64 status) -- 2.51.2.vfs.0.1
