€•R4      Œsphinx.addnodes”Œdocument”“”)”}”(Œ	rawsource”Œ ”Œchildren”]”(Œtranslations”ŒLanguagesNode”“”)”}”(hhh]”(h Œpending_xref”“”)”}”(hhh]”Œdocutils.nodes”ŒText”“”ŒChinese (Simplified)”…””}”Œparent”hsbaŒ
attributes”}”(Œids”]”Œclasses”]”Œnames”]”Œdupnames”]”Œbackrefs”]”Œ	refdomain”Œstd”Œreftype”Œdoc”Œ	reftarget”Œ-/translations/zh_CN/filesystems/fuse-io-uring”Œmodname”NŒ	classname”NŒrefexplicit”ˆuŒtagname”hhhubh)”}”(hhh]”hŒChinese (Traditional)”…””}”hh2sbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ-/translations/zh_TW/filesystems/fuse-io-uring”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒItalian”…””}”hhFsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ-/translations/it_IT/filesystems/fuse-io-uring”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒJapanese”…””}”hhZsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ-/translations/ja_JP/filesystems/fuse-io-uring”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒKorean”…””}”hhnsbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ-/translations/ko_KR/filesystems/fuse-io-uring”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubh)”}”(hhh]”hŒSpanish”…””}”hh‚sbah}”(h]”h ]”h"]”h$]”h&]”Œ	refdomain”h)Œreftype”h+Œ	reftarget”Œ-/translations/sp_SP/filesystems/fuse-io-uring”Œmodname”NŒ	classname”NŒrefexplicit”ˆuh1hhhubeh}”(h]”h ]”h"]”h$]”h&]”Œcurrent_language”ŒEnglish”uh1h
hhŒ	_document”hŒsource”NŒline”NubhŒcomment”“”)”}”(hŒ SPDX-License-Identifier: GPL-2.0”h]”hŒ SPDX-License-Identifier: GPL-2.0”…””}”hh£sbah}”(h]”h ]”h"]”h$]”h&]”Œ	xml:space”Œpreserve”uh1h¡hhhžhhŸŒG/var/lib/git/docbuild/linux/Documentation/filesystems/fuse-io-uring.rst”h KubhŒsection”“”)”}”(hhh]”(hŒtitle”“”)”}”(hŒ'FUSE-over-io-uring design documentation”h]”hŒ'FUSE-over-io-uring design documentation”…””}”(hh»hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¹hh¶hžhhŸh³h KubhŒ	paragraph”“”)”}”(hŒªThis documentation covers basic details how the fuse
kernel/userspace communication through io-uring is configured
and works. For generic details about FUSE see fuse.rst.”h]”hŒªThis documentation covers basic details how the fuse
kernel/userspace communication through io-uring is configured
and works. For generic details about FUSE see fuse.rst.”…””}”(hhËhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÉhŸh³h Khh¶hžhubhÊ)”}”(hŒ`This document also covers the current interface, which is
still in development and might change.”h]”hŒ`This document also covers the current interface, which is
still in development and might change.”…””}”(hhÙhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÉhŸh³h Khh¶hžhubhµ)”}”(hhh]”(hº)”}”(hŒLimitations”h]”hŒLimitations”…””}”(hhêhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¹hhçhžhhŸh³h KubhÊ)”}”(hŒîAs of now not all requests types are supported through io-uring, userspace
is required to also handle requests through /dev/fuse after io-uring setup
is complete. Specifically notifications (initiated from the daemon side)
and interrupts.”h]”hŒîAs of now not all requests types are supported through io-uring, userspace
is required to also handle requests through /dev/fuse after io-uring setup
is complete. Specifically notifications (initiated from the daemon side)
and interrupts.”…””}”(hhøhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÉhŸh³h Khhçhžhubeh}”(h]”Œlimitations”ah ]”h"]”Œlimitations”ah$]”h&]”uh1h´hh¶hžhhŸh³h Kubhµ)”}”(hhh]”(hº)”}”(hŒFuse io-uring configuration”h]”hŒFuse io-uring configuration”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¹hj  hžhhŸh³h KubhÊ)”}”(hŒxFuse kernel requests are queued through the classical /dev/fuse
read/write interface - until io-uring setup is complete.”h]”hŒxFuse kernel requests are queued through the classical /dev/fuse
read/write interface - until io-uring setup is complete.”…””}”(hj  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÉhŸh³h Khj  hžhubhÊ)”}”(hX  In order to set up fuse-over-io-uring fuse-server (user-space)
needs to submit SQEs (opcode = IORING_OP_URING_CMD) to the /dev/fuse
connection file descriptor. Initial submit is with the sub command
FUSE_URING_REQ_REGISTER, which will just register entries to be
available in the kernel.”h]”hX  In order to set up fuse-over-io-uring fuse-server (user-space)
needs to submit SQEs (opcode = IORING_OP_URING_CMD) to the /dev/fuse
connection file descriptor. Initial submit is with the sub command
FUSE_URING_REQ_REGISTER, which will just register entries to be
available in the kernel.”…””}”(hj-  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÉhŸh³h Khj  hžhubhÊ)”}”(hX©  Once at least one entry per queue is submitted, kernel starts
to enqueue to ring queues.
Note, every CPU core has its own fuse-io-uring queue.
Userspace handles the CQE/fuse-request and submits the result as
subcommand FUSE_URING_REQ_COMMIT_AND_FETCH - kernel completes
the requests and also marks the entry available again. If there are
pending requests waiting the request will be immediately submitted
to the daemon again.”h]”hX©  Once at least one entry per queue is submitted, kernel starts
to enqueue to ring queues.
Note, every CPU core has its own fuse-io-uring queue.
Userspace handles the CQE/fuse-request and submits the result as
subcommand FUSE_URING_REQ_COMMIT_AND_FETCH - kernel completes
the requests and also marks the entry available again. If there are
pending requests waiting the request will be immediately submitted
to the daemon again.”…””}”(hj;  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÉhŸh³h K!hj  hžhubhÊ)”}”(hŒInitial SQE
-----------::”h]”hŒInitial SQE
-----------:”…””}”(hjI  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÉhŸh³h K*hj  hžhubhŒliteral_block”“”)”}”(hXN  |                                    |  FUSE filesystem daemon
|                                    |
|                                    |  >io_uring_submit()
|                                    |   IORING_OP_URING_CMD /
|                                    |   FUSE_URING_CMD_REGISTER
|                                    |  [wait cqe]
|                                    |   >io_uring_wait_cqe() or
|                                    |   >io_uring_submit_and_wait()
|                                    |
|  >fuse_uring_cmd()                 |
|   >fuse_uring_register()           |”h]”hXN  |                                    |  FUSE filesystem daemon
|                                    |
|                                    |  >io_uring_submit()
|                                    |   IORING_OP_URING_CMD /
|                                    |   FUSE_URING_CMD_REGISTER
|                                    |  [wait cqe]
|                                    |   >io_uring_wait_cqe() or
|                                    |   >io_uring_submit_and_wait()
|                                    |
|  >fuse_uring_cmd()                 |
|   >fuse_uring_register()           |”…””}”hjY  sbah}”(h]”h ]”h"]”h$]”h&]”h±h²uh1jW  hŸh³h K-hj  hžhubhÊ)”}”(hŒ7Sending requests with CQEs
--------------------------::”h]”hŒ6Sending requests with CQEs
--------------------------:”…””}”(hjg  hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hÉhŸh³h K:hj  hžhubjX  )”}”(hX,  |                                           |  FUSE filesystem daemon
|                                           |  [waiting for CQEs]
|  "rm /mnt/fuse/file"                      |
|                                           |
|  >sys_unlink()                            |
|    >fuse_unlink()                         |
|      [allocate request]                   |
|      >fuse_send_one()                     |
|        ...                                |
|       >fuse_uring_queue_fuse_req          |
|        [queue request on fg queue]        |
|         >fuse_uring_add_req_to_ring_ent() |
|         ...                               |
|          >fuse_uring_copy_to_ring()       |
|          >io_uring_cmd_done()             |
|       >request_wait_answer()              |
|         [sleep on req->waitq]             |
|                                           |  [receives and handles CQE]
|                                           |  [submit result and fetch next]
|                                           |  >io_uring_submit()
|                                           |   IORING_OP_URING_CMD/
|                                           |   FUSE_URING_CMD_COMMIT_AND_FETCH
|  >fuse_uring_cmd()                        |
|   >fuse_uring_commit_fetch()              |
|    >fuse_uring_commit()                   |
|     >fuse_uring_copy_from_ring()          |
|      [ copy the result to the fuse req]   |
|     >fuse_uring_req_end()                 |
|      >fuse_request_end()                  |
|       [wake up req->waitq]                |
|    >fuse_uring_next_fuse_req              |
|       [wait or handle next req]           |
|                                           |
|       [req->waitq woken up]               |
|    <fuse_unlink()                         |
|  <sys_unlink()                            |”h]”hX,  |                                           |  FUSE filesystem daemon
|                                           |  [waiting for CQEs]
|  "rm /mnt/fuse/file"                      |
|                                           |
|  >sys_unlink()                            |
|    >fuse_unlink()                         |
|      [allocate request]                   |
|      >fuse_send_one()                     |
|        ...                                |
|       >fuse_uring_queue_fuse_req          |
|        [queue request on fg queue]        |
|         >fuse_uring_add_req_to_ring_ent() |
|         ...                               |
|          >fuse_uring_copy_to_ring()       |
|          >io_uring_cmd_done()             |
|       >request_wait_answer()              |
|         [sleep on req->waitq]             |
|                                           |  [receives and handles CQE]
|                                           |  [submit result and fetch next]
|                                           |  >io_uring_submit()
|                                           |   IORING_OP_URING_CMD/
|                                           |   FUSE_URING_CMD_COMMIT_AND_FETCH
|  >fuse_uring_cmd()                        |
|   >fuse_uring_commit_fetch()              |
|    >fuse_uring_commit()                   |
|     >fuse_uring_copy_from_ring()          |
|      [ copy the result to the fuse req]   |
|     >fuse_uring_req_end()                 |
|      >fuse_request_end()                  |
|       [wake up req->waitq]                |
|    >fuse_uring_next_fuse_req              |
|       [wait or handle next req]           |
|                                           |
|       [req->waitq woken up]               |
|    <fuse_unlink()                         |
|  <sys_unlink()                            |”…””}”hju  sbah}”(h]”h ]”h"]”h$]”h&]”h±h²uh1jW  hŸh³h K=hj  hžhubeh}”(h]”Œfuse-io-uring-configuration”ah ]”h"]”Œfuse io-uring configuration”ah$]”h&]”uh1h´hh¶hžhhŸh³h Kubeh}”(h]”Œ'fuse-over-io-uring-design-documentation”ah ]”h"]”Œ'fuse-over-io-uring design documentation”ah$]”h&]”uh1h´hhhžhhŸh³h Kubeh}”(h]”h ]”h"]”h$]”h&]”Œsource”h³uh1hŒcurrent_source”NŒcurrent_line”NŒsettings”Œdocutils.frontend”ŒValues”“”)”}”(h¹NŒ	generator”NŒ	datestamp”NŒsource_link”NŒ
source_url”NŒtoc_backlinks”Œentry”Œfootnote_backlinks”KŒsectnum_xform”KŒstrip_comments”NŒstrip_elements_with_classes”NŒstrip_classes”NŒreport_level”KŒ
halt_level”KŒexit_status_level”KŒdebug”NŒwarning_stream”NŒ	traceback”ˆŒinput_encoding”Œ	utf-8-sig”Œinput_encoding_error_handler”Œstrict”Œoutput_encoding”Œutf-8”Œoutput_encoding_error_handler”j¶  Œerror_encoding”Œutf-8”Œerror_encoding_error_handler”Œbackslashreplace”Œlanguage_code”Œen”Œrecord_dependencies”NŒconfig”NŒ	id_prefix”hŒauto_id_prefix”Œid”Œdump_settings”NŒdump_internals”NŒdump_transforms”NŒdump_pseudo_xml”NŒexpose_internals”NŒstrict_visitor”NŒ_disable_config”NŒ_source”h³Œ_destination”NŒ_config_files”]”Œ7/var/lib/git/docbuild/linux/Documentation/docutils.conf”aŒfile_insertion_enabled”ˆŒraw_enabled”KŒline_length_limit”M'Œpep_references”NŒpep_base_url”Œhttps://peps.python.org/”Œpep_file_url_template”Œpep-%04d”Œrfc_references”NŒrfc_base_url”Œ&https://datatracker.ietf.org/doc/html/”Œ	tab_width”KŒtrim_footnote_reference_space”‰Œsyntax_highlight”Œlong”Œsmart_quotes”ˆŒsmartquotes_locales”]”Œcharacter_level_inline_markup”‰Œdoctitle_xform”‰Œdocinfo_xform”KŒsectsubtitle_xform”‰Œimage_loading”Œlink”Œembed_stylesheet”‰Œcloak_email_addresses”ˆŒsection_self_link”‰Œenv”NubŒreporter”NŒindirect_targets”]”Œsubstitution_defs”}”Œsubstitution_names”}”Œrefnames”}”Œrefids”}”Œnameids”}”(j  j  j  j  jˆ  j…  uŒ	nametypes”}”(j  ‰j  ‰jˆ  ‰uh}”(j  h¶j  hçj…  j  uŒfootnote_refs”}”Œcitation_refs”}”Œautofootnotes”]”Œautofootnote_refs”]”Œsymbol_footnotes”]”Œsymbol_footnote_refs”]”Œ	footnotes”]”Œ	citations”]”Œautofootnote_start”KŒsymbol_footnote_start”K Œ
id_counter”Œcollections”ŒCounter”“”}”…”R”Œparse_messages”]”Œtransform_messages”]”Œtransformer”NŒinclude_log”]”Œ
decoration”Nhžhub.