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author | Marcel Ziswiler <marcel.ziswiler@toradex.com> | 2020-05-21 00:54:36 +0200 |
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committer | Marcel Ziswiler <marcel.ziswiler@toradex.com> | 2020-05-21 00:54:36 +0200 |
commit | 135d39dcedcedd1f44ea0bba52f15ac5922c114f (patch) | |
tree | 12379fc8ef7489eaca1c7245f8bd6af74c619a8f /Documentation/virtual/kvm/api.txt | |
parent | 187764bd111b27783b6d68ffb3b3dbb3a9bafd38 (diff) | |
parent | 1279cd128bba968ebe0a2df7f7ae38bae90250ef (diff) |
Merge remote-tracking branch 'remotes/fslc/4.9-2.3.x-imx' into toradex_4.9-2.3.x-imx-next
Conflicts:
sound/soc/codecs/sgtl5000.c
sound/soc/fsl/imx-sgtl5000.c
Diffstat (limited to 'Documentation/virtual/kvm/api.txt')
-rw-r--r-- | Documentation/virtual/kvm/api.txt | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 3ff58a8ffabb..d1908e50b506 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -13,7 +13,7 @@ of a virtual machine. The ioctls belong to three classes - VM ioctls: These query and set attributes that affect an entire virtual machine, for example memory layout. In addition a VM ioctl is used to - create virtual cpus (vcpus). + create virtual cpus (vcpus) and devices. Only run VM ioctls from the same process (address space) that was used to create the VM. @@ -24,6 +24,11 @@ of a virtual machine. The ioctls belong to three classes Only run vcpu ioctls from the same thread that was used to create the vcpu. + - device ioctls: These query and set attributes that control the operation + of a single device. + + device ioctls must be issued from the same process (address space) that + was used to create the VM. 2. File descriptors ------------------- @@ -32,10 +37,11 @@ The kvm API is centered around file descriptors. An initial open("/dev/kvm") obtains a handle to the kvm subsystem; this handle can be used to issue system ioctls. A KVM_CREATE_VM ioctl on this handle will create a VM file descriptor which can be used to issue VM -ioctls. A KVM_CREATE_VCPU ioctl on a VM fd will create a virtual cpu -and return a file descriptor pointing to it. Finally, ioctls on a vcpu -fd can be used to control the vcpu, including the important task of -actually running guest code. +ioctls. A KVM_CREATE_VCPU or KVM_CREATE_DEVICE ioctl on a VM fd will +create a virtual cpu or device and return a file descriptor pointing to +the new resource. Finally, ioctls on a vcpu or device fd can be used +to control the vcpu or device. For vcpus, this includes the important +task of actually running guest code. In general file descriptors can be migrated among processes by means of fork() and the SCM_RIGHTS facility of unix domain socket. These |