€•ð4Œsphinx.addnodes”Œdocument”“”)”}”(Œ rawsource”Œ”Œchildren”]”(Œ translations”Œ LanguagesNode”“”)”}”(hhh]”(hŒ pending_xref”“”)”}”(hhh]”Œdocutils.nodes”ŒText”“”ŒChinese (Simplified)”…””}”Œparent”hsbaŒ attributes”}”(Œids”]”Œclasses”]”Œnames”]”Œdupnames”]”Œbackrefs”]”Œ refdomain”Œstd”Œreftype”Œdoc”Œ reftarget”Œ(/translations/zh_CN/filesystems/virtiofs”Œmodname”NŒ classname”NŒ refexplicit”ˆuŒtagname”hhh ubh)”}”(hhh]”hŒChinese (Traditional)”…””}”hh2sbah}”(h]”h ]”h"]”h$]”h&]”Œ refdomain”h)Œreftype”h+Œ reftarget”Œ(/translations/zh_TW/filesystems/virtiofs”Œmodname”NŒ classname”NŒ refexplicit”ˆuh1hhh ubh)”}”(hhh]”hŒItalian”…””}”hhFsbah}”(h]”h ]”h"]”h$]”h&]”Œ refdomain”h)Œreftype”h+Œ reftarget”Œ(/translations/it_IT/filesystems/virtiofs”Œmodname”NŒ classname”NŒ refexplicit”ˆuh1hhh ubh)”}”(hhh]”hŒJapanese”…””}”hhZsbah}”(h]”h ]”h"]”h$]”h&]”Œ refdomain”h)Œreftype”h+Œ reftarget”Œ(/translations/ja_JP/filesystems/virtiofs”Œmodname”NŒ classname”NŒ refexplicit”ˆuh1hhh ubh)”}”(hhh]”hŒKorean”…””}”hhnsbah}”(h]”h ]”h"]”h$]”h&]”Œ refdomain”h)Œreftype”h+Œ reftarget”Œ(/translations/ko_KR/filesystems/virtiofs”Œmodname”NŒ classname”NŒ refexplicit”ˆuh1hhh ubh)”}”(hhh]”hŒPortuguese (Brazilian)”…””}”hh‚sbah}”(h]”h ]”h"]”h$]”h&]”Œ refdomain”h)Œreftype”h+Œ reftarget”Œ(/translations/pt_BR/filesystems/virtiofs”Œmodname”NŒ classname”NŒ refexplicit”ˆuh1hhh ubh)”}”(hhh]”hŒSpanish”…””}”hh–sbah}”(h]”h ]”h"]”h$]”h&]”Œ refdomain”h)Œreftype”h+Œ reftarget”Œ(/translations/sp_SP/filesystems/virtiofs”Œmodname”NŒ classname”NŒ refexplicit”ˆuh1hhh ubeh}”(h]”h ]”h"]”h$]”h&]”Œcurrent_language”ŒEnglish”uh1h hhŒ _document”hŒsource”NŒline”NubhŒcomment”“”)”}”(hŒ SPDX-License-Identifier: GPL-2.0”h]”hŒ SPDX-License-Identifier: GPL-2.0”…””}”hh·sbah}”(h]”h ]”h"]”h$]”h&]”Œ xml:space”Œpreserve”uh1hµhhh²hh³ŒB/var/lib/git/docbuild/linux/Documentation/filesystems/virtiofs.rst”h´KubhŒtarget”“”)”}”(hŒ.. _virtiofs_index:”h]”h}”(h]”h ]”h"]”h$]”h&]”Œrefid”Œvirtiofs-index”uh1hÈh´Khhh²hh³hÇubhŒsection”“”)”}”(hhh]”(hŒtitle”“”)”}”(hŒ3virtiofs: virtio-fs host<->guest shared file system”h]”hŒ3virtiofs: virtio-fs host<->guest shared file system”…””}”(hhÝh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÛhhØh²hh³hÇh´KubhŒ bullet_list”“”)”}”(hhh]”hŒ list_item”“”)”}”(hŒ!Copyright (C) 2019 Red Hat, Inc. ”h]”hŒ paragraph”“”)”}”(hŒ Copyright (C) 2019 Red Hat, Inc.”h]”hŒ Copyright (C) 2019 Red Hat, Inc.”…””}”(hhøh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1höh³hÇh´K hhòubah}”(h]”h ]”h"]”h$]”h&]”uh1hðhhíh²hh³hÇh´Nubah}”(h]”h ]”h"]”h$]”h&]”Œbullet”Œ-”uh1hëh³hÇh´K hhØh²hubh×)”}”(hhh]”(hÜ)”}”(hŒ Introduction”h]”hŒ Introduction”…””}”(hjh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÛhjh²hh³hÇh´K ubh÷)”}”(hŒÚThe virtiofs file system for Linux implements a driver for the paravirtualized VIRTIO "virtio-fs" device for guest<->host file system sharing. It allows a guest to mount a directory that has been exported on the host.”h]”hŒÞThe virtiofs file system for Linux implements a driver for the paravirtualized VIRTIO “virtio-fs†device for guest<->host file system sharing. It allows a guest to mount a directory that has been exported on the host.”…””}”(hj%h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1höh³hÇh´K hjh²hubh÷)”}”(hX+Guests often require access to files residing on the host or remote systems. Use cases include making files available to new guests during installation, booting from a root file system located on the host, persistent storage for stateless or ephemeral guests, and sharing a directory between guests.”h]”hX+Guests often require access to files residing on the host or remote systems. Use cases include making files available to new guests during installation, booting from a root file system located on the host, persistent storage for stateless or ephemeral guests, and sharing a directory between guests.”…””}”(hj3h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1höh³hÇh´Khjh²hubh÷)”}”(hX1Although it is possible to use existing network file systems for some of these tasks, they require configuration steps that are hard to automate and they expose the storage network to the guest. The virtio-fs device was designed to solve these problems by providing file system access without networking.”h]”hX1Although it is possible to use existing network file systems for some of these tasks, they require configuration steps that are hard to automate and they expose the storage network to the guest. The virtio-fs device was designed to solve these problems by providing file system access without networking.”…””}”(hjAh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1höh³hÇh´Khjh²hubh÷)”}”(hŒ¸Furthermore the virtio-fs device takes advantage of the co-location of the guest and host to increase performance and provide semantics that are not possible with network file systems.”h]”hŒ¸Furthermore the virtio-fs device takes advantage of the co-location of the guest and host to increase performance and provide semantics that are not possible with network file systems.”…””}”(hjOh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1höh³hÇh´Khjh²hubeh}”(h]”Œ introduction”ah ]”h"]”Œ introduction”ah$]”h&]”uh1hÖhhØh²hh³hÇh´K ubh×)”}”(hhh]”(hÜ)”}”(hŒUsage”h]”hŒUsage”…””}”(hjhh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÛhjeh²hh³hÇh´K ubh÷)”}”(hŒ0Mount file system with tag ``myfs`` on ``/mnt``:”h]”(hŒMount file system with tag ”…””}”(hjvh²hh³Nh´NubhŒliteral”“”)”}”(hŒ``myfs``”h]”hŒmyfs”…””}”(hj€h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j~hjvubhŒ on ”…””}”(hjvh²hh³Nh´Nubj)”}”(hŒ``/mnt``”h]”hŒ/mnt”…””}”(hj’h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1j~hjvubhŒ:”…””}”(hjvh²hh³Nh´Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1höh³hÇh´K!hjeh²hubhŒ literal_block”“”)”}”(hŒ"guest# mount -t virtiofs myfs /mnt”h]”hŒ"guest# mount -t virtiofs myfs /mnt”…””}”hj¬sbah}”(h]”h ]”h"]”h$]”h&]”hÅhÆŒforce”‰Œlanguage”Œsh”Œhighlight_args”}”uh1jªh³hÇh´K#hjeh²hubh÷)”}”(hŒfPlease see https://virtio-fs.gitlab.io/ for details on how to configure QEMU and the virtiofsd daemon.”h]”(hŒ Please see ”…””}”(hj¿h²hh³Nh´NubhŒ reference”“”)”}”(hŒhttps://virtio-fs.gitlab.io/”h]”hŒhttps://virtio-fs.gitlab.io/”…””}”(hjÉh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”Œrefuri”jËuh1jÇhj¿ubhŒ? for details on how to configure QEMU and the virtiofsd daemon.”…””}”(hj¿h²hh³Nh´Nubeh}”(h]”h ]”h"]”h$]”h&]”uh1höh³hÇh´K'hjeh²hubh×)”}”(hhh]”(hÜ)”}”(hŒ Mount options”h]”hŒ Mount options”…””}”(hjåh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÛhjâh²hh³hÇh´K+ubh÷)”}”(hŒ}virtiofs supports general VFS mount options, for example, remount, ro, rw, context, etc. It also supports FUSE mount options.”h]”hŒ}virtiofs supports general VFS mount options, for example, remount, ro, rw, context, etc. It also supports FUSE mount options.”…””}”(hjóh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1höh³hÇh´K-hjâh²hubh×)”}”(hhh]”(hÜ)”}”(hŒatime behavior”h]”hŒatime behavior”…””}”(hjh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÛhjh²hh³hÇh´K1ubh÷)”}”(hŒÎThe atime-related mount options, for example, noatime, strictatime, are ignored. The atime behavior for virtiofs is the same as the underlying filesystem of the directory that has been exported on the host.”h]”hŒÎThe atime-related mount options, for example, noatime, strictatime, are ignored. The atime behavior for virtiofs is the same as the underlying filesystem of the directory that has been exported on the host.”…””}”(hjh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1höh³hÇh´K3hjh²hubeh}”(h]”Œatime-behavior”ah ]”h"]”Œatime behavior”ah$]”h&]”uh1hÖhjâh²hh³hÇh´K1ubeh}”(h]”Œ mount-options”ah ]”h"]”Œ mount options”ah$]”h&]”uh1hÖhjeh²hh³hÇh´K+ubeh}”(h]”Œusage”ah ]”h"]”Œusage”ah$]”h&]”uh1hÖhhØh²hh³hÇh´K ubh×)”}”(hhh]”(hÜ)”}”(hŒ Internals”h]”hŒ Internals”…””}”(hj;h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÛhj8h²hh³hÇh´K9ubh÷)”}”(hX\Since the virtio-fs device uses the FUSE protocol for file system requests, the virtiofs file system for Linux is integrated closely with the FUSE file system client. The guest acts as the FUSE client while the host acts as the FUSE server. The /dev/fuse interface between the kernel and userspace is replaced with the virtio-fs device interface.”h]”hX\Since the virtio-fs device uses the FUSE protocol for file system requests, the virtiofs file system for Linux is integrated closely with the FUSE file system client. The guest acts as the FUSE client while the host acts as the FUSE server. The /dev/fuse interface between the kernel and userspace is replaced with the virtio-fs device interface.”…””}”(hjIh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1höh³hÇh´K:hj8h²hubh÷)”}”(hŒ¯FUSE requests are placed into a virtqueue and processed by the host. The response portion of the buffer is filled in by the host and the guest handles the request completion.”h]”hŒ¯FUSE requests are placed into a virtqueue and processed by the host. 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