iommu/ioasid: Introduce a helper to check for valid PASIDs

mainline inclusion
from mainline-v5.18
commit 7a5fbc9b
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I596WO


CVE: NA

Intel-SIG: commit 7a5fbc9b iommu/ioasid: Introduce a helper to check for valid PASIDs.
Incremental backporting patches for DSA/IAA on Intel Xeon platform.

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Define a pasid_valid() helper to check if a given PASID is valid.

  [ bp: Massage commit message. ]

Suggested-by: Ashok Raj <ashok.raj@intel.com>
Suggested-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20220207230254.3342514-4-fenghua.yu@intel.com


Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>