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@ -15,8 +15,9 @@ Virtual filesystem |
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------------------ |
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The core functionality lies in a virtual file system based on a 9p file server |
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interface (`Notes on the Plan 9 Kernel Source`_). The implementation permits |
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exposing virtual files, firmware drivers, and file blobs. |
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interface (`Notes on the Plan 9 Kernel Source`_ and |
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`Linux 9p remote filesystem protocol`_). |
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The implementation permits exposing virtual files, firmware drivers, and file blobs. |
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Namespace |
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~~~~~~~~~ |
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@ -77,10 +78,10 @@ SMC interface |
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------------- |
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The communication with the 9p layer in BL31 is made through an SMC conduit |
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(`SMC Calling Convention PDD`_), using a specific SiP Function Id. An NS shared |
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buffer is used to pass path string parameters, or e.g. to exchange data on a |
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read operation. Refer to `ARM SiP Services`_ for a description of the SMC |
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interface. |
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(`SMC Calling Convention PDD`_), using a specific SiP Function Id. An NS |
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shared buffer is used to pass path string parameters, or e.g. to exchange |
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data on a read operation. Refer to `ARM SiP Services`_ for a description |
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of the SMC interface. |
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Security considerations |
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----------------------- |
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@ -114,17 +115,9 @@ The SMC interface is accessible from an NS environment, that is: |
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- a Linux kernel driver running at NS-EL1 |
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- a Linux userspace application through the kernel driver |
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References |
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---------- |
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.. [#] `SMC Calling Convention PDD`_ |
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.. [#] `Notes on the Plan 9 Kernel Source`_ |
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.. [#] `Linux 9p remote filesystem protocol`_ |
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.. [#] `ARM SiP Services`_ |
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-------------- |
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*Copyright (c) 2019, Arm Limited and Contributors. All rights reserved.* |
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*Copyright (c) 2019-2020, Arm Limited and Contributors. All rights reserved.* |
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.. _SMC Calling Convention PDD: http://infocenter.arm.com/help/topic/com.arm.doc.den0028b/ |
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.. _Notes on the Plan 9 Kernel Source: http://lsub.org/who/nemo/9.pdf |
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