Merge tag 'ntb-3.13' of git://github.com/jonmason/ntb

[linux-drm-fsl-dcu.git] / Documentation / virtual / kvm / locking.txt

diff --git a/Documentation/virtual/kvm/locking.txt b/Documentation/virtual/kvm/locking.txt
index 41b7ac9884b5ebdeaba602077bebb11efebcc648..f8869410d40ce8ba4eac30d3193f28aedb8383a6 100644 (file)
--- a/Documentation/virtual/kvm/locking.txt
+++ b/Documentation/virtual/kvm/locking.txt
@@ -132,10 +132,14 @@ See the comments in spte_has_volatile_bits() and mmu_spte_update().
 ------------
 
 Name:          kvm_lock
-Type:          raw_spinlock
+Type:          spinlock_t
 Arch:          any
 Protects:      - vm_list
-               - hardware virtualization enable/disable
+
+Name:          kvm_count_lock
+Type:          raw_spinlock_t
+Arch:          any
+Protects:      - hardware virtualization enable/disable
 Comment:       'raw' because hardware enabling/disabling must be atomic /wrt
                migration.
 
@@ -151,3 +155,14 @@ Type:              spinlock_t
 Arch:          any
 Protects:      -shadow page/shadow tlb entry
 Comment:       it is a spinlock since it is used in mmu notifier.
+
+Name:          kvm->srcu
+Type:          srcu lock
+Arch:          any
+Protects:      - kvm->memslots
+               - kvm->buses
+Comment:       The srcu read lock must be held while accessing memslots (e.g.
+               when using gfn_to_* functions) and while accessing in-kernel
+               MMIO/PIO address->device structure mapping (kvm->buses).
+               The srcu index can be stored in kvm_vcpu->srcu_idx per vcpu
+               if it is needed by multiple functions.