qemu-nbd: asynchronous operation

Using coroutines enable asynchronous operation on both the network and
the block side.  Network can be owned by two coroutines at the same time,
one writing and one reading.  On the send side, mutual exclusion is
guaranteed by a CoMutex.  On the receive side, mutual exclusion is
guaranteed because new coroutines immediately start receiving data,
and no new coroutines are created as long as the previous one is receiving.

Between receive and send, qemu-nbd can have an arbitrary number of
in-flight block transfers.  Throttling is implemented by the next
patch.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
1 file changed
tree: 6f411fa003a3784224c96fce790cce970d14b71e
  1. audio/
  2. block/
  3. bsd-user/
  4. darwin-user/
  5. default-configs/
  6. docs/
  7. fpu/
  8. fsdev/
  9. gdb-xml/
  10. hw/
  11. libcacard/
  12. linux-headers/
  13. linux-user/
  14. net/
  15. pc-bios/
  16. qapi/
  17. qga/
  18. QMP/
  19. roms/
  20. scripts/
  21. slirp/
  22. sysconfigs/
  23. target-alpha/
  24. target-arm/
  25. target-cris/
  26. target-i386/
  27. target-lm32/
  28. target-m68k/
  29. target-microblaze/
  30. target-mips/
  31. target-ppc/
  32. target-s390x/
  33. target-sh4/
  34. target-sparc/
  35. target-unicore32/
  36. target-xtensa/
  37. tcg/
  38. tests/
  39. trace/
  40. ui/
  41. .gitignore
  42. .gitmodules
  43. .mailmap
  44. a.out.h
  45. acl.c
  46. acl.h
  47. aes.c
  48. aes.h
  49. aio.c
  50. alpha-dis.c
  51. alpha.ld
  52. arch_init.c
  53. arch_init.h
  54. arm-dis.c
  55. arm-semi.c
  56. arm.ld
  57. async.c
  58. balloon.c
  59. balloon.h
  60. bitmap.c
  61. bitmap.h
  62. bitops.c
  63. bitops.h
  64. block-migration.c
  65. block-migration.h
  66. block.c
  67. block.h
  68. block_int.h
  69. blockdev.c
  70. blockdev.h
  71. bswap.h
  72. bt-host.c
  73. bt-host.h
  74. bt-vhci.c
  75. buffered_file.c
  76. buffered_file.h
  77. cache-utils.c
  78. cache-utils.h
  79. Changelog
  80. check-qdict.c
  81. check-qfloat.c
  82. check-qint.c
  83. check-qjson.c
  84. check-qlist.c
  85. check-qstring.c
  86. cmd.c
  87. cmd.h
  88. CODING_STYLE
  89. compatfd.c
  90. compatfd.h
  91. compiler.h
  92. config.h
  93. configure
  94. console.c
  95. console.h
  96. COPYING
  97. COPYING.LIB
  98. coroutine-gthread.c
  99. coroutine-ucontext.c
  100. coroutine-win32.c
  101. cpu-all.h
  102. cpu-common.h
  103. cpu-defs.h
  104. cpu-exec.c
  105. cpus.c
  106. cpus.h
  107. cris-dis.c
  108. cursor.c
  109. cursor_hidden.xpm
  110. cursor_left_ptr.xpm
  111. cutils.c
  112. def-helper.h
  113. device_tree.c
  114. device_tree.h
  115. dis-asm.h
  116. disas.c
  117. disas.h
  118. dma-helpers.c
  119. dma.h
  120. dyngen-exec.h
  121. elf.h
  122. envlist.c
  123. envlist.h
  124. error.c
  125. error.h
  126. error_int.h
  127. event_notifier.c
  128. event_notifier.h
  129. exec-all.h
  130. exec-memory.h
  131. exec-obsolete.h
  132. exec.c
  133. gdbstub.c
  134. gdbstub.h
  135. gen-icount.h
  136. HACKING
  137. hmp-commands.hx
  138. hmp.c
  139. hmp.h
  140. host-utils.c
  141. host-utils.h
  142. hppa-dis.c
  143. hppa.ld
  144. i386-dis.c
  145. i386.ld
  146. ia64-dis.c
  147. ia64.ld
  148. input.c
  149. int128.h
  150. iohandler.c
  151. ioport-user.c
  152. ioport.c
  153. ioport.h
  154. iorange.h
  155. iov.c
  156. iov.h
  157. json-lexer.c
  158. json-lexer.h
  159. json-parser.c
  160. json-parser.h
  161. json-streamer.c
  162. json-streamer.h
  163. kvm-all.c
  164. kvm-stub.c
  165. kvm.h
  166. libfdt_env.h
  167. LICENSE
  168. linux-aio.c
  169. m68k-dis.c
  170. m68k-semi.c
  171. m68k.ld
  172. main-loop.c
  173. main-loop.h
  174. MAINTAINERS
  175. Makefile
  176. Makefile.dis
  177. Makefile.hw
  178. Makefile.objs
  179. Makefile.target
  180. Makefile.user
  181. memory.c
  182. memory.h
  183. microblaze-dis.c
  184. migration-exec.c
  185. migration-fd.c
  186. migration-tcp.c
  187. migration-unix.c
  188. migration.c
  189. migration.h
  190. mips-dis.c
  191. mips.ld
  192. module.c
  193. module.h
  194. monitor.c
  195. monitor.h
  196. nbd.c
  197. nbd.h
  198. net.c
  199. net.h
  200. notify.c
  201. notify.h
  202. os-posix.c
  203. os-win32.c
  204. osdep.c
  205. osdep.h
  206. oslib-posix.c
  207. oslib-win32.c
  208. path.c
  209. pci-ids.txt
  210. pflib.c
  211. pflib.h
  212. poison.h
  213. posix-aio-compat.c
  214. ppc-dis.c
  215. ppc.ld
  216. ppc64.ld
  217. qapi-schema-guest.json
  218. qapi-schema-test.json
  219. qapi-schema.json
  220. qbool.c
  221. qbool.h
  222. qdict-test-data.txt
  223. qdict.c
  224. qdict.h
  225. qemu-aio.h
  226. qemu-barrier.h
  227. qemu-char.c
  228. qemu-char.h
  229. qemu-common.h
  230. qemu-config.c
  231. qemu-config.h
  232. qemu-coroutine-int.h
  233. qemu-coroutine-io.c
  234. qemu-coroutine-lock.c
  235. qemu-coroutine.c
  236. qemu-coroutine.h
  237. qemu-doc.texi
  238. qemu-error.c
  239. qemu-error.h
  240. qemu-ga.c
  241. qemu-img-cmds.hx
  242. qemu-img.c
  243. qemu-img.texi
  244. qemu-io.c
  245. qemu-lock.h
  246. qemu-log.h
  247. qemu-nbd.c
  248. qemu-nbd.texi
  249. qemu-objects.h
  250. qemu-option.c
  251. qemu-option.h
  252. qemu-options-wrapper.h
  253. qemu-options.h
  254. qemu-options.hx
  255. qemu-os-posix.h
  256. qemu-os-win32.h
  257. qemu-progress.c
  258. qemu-queue.h
  259. qemu-sockets.c
  260. qemu-tech.texi
  261. qemu-thread-posix.c
  262. qemu-thread-posix.h
  263. qemu-thread-win32.c
  264. qemu-thread-win32.h
  265. qemu-thread.h
  266. qemu-timer-common.c
  267. qemu-timer.c
  268. qemu-timer.h
  269. qemu-tls.h
  270. qemu-tool.c
  271. qemu-x509.h
  272. qemu-xattr.h
  273. qemu.sasl
  274. qemu_socket.h
  275. qerror.c
  276. qerror.h
  277. qfloat.c
  278. qfloat.h
  279. qint.c
  280. qint.h
  281. qjson.c
  282. qjson.h
  283. qlist.c
  284. qlist.h
  285. qmp-commands.hx
  286. qmp.c
  287. qobject.h
  288. qstring.c
  289. qstring.h
  290. range.h
  291. readline.c
  292. readline.h
  293. README
  294. rules.mak
  295. s390-dis.c
  296. s390.ld
  297. savevm.c
  298. sh4-dis.c
  299. softmmu-semi.h
  300. softmmu_defs.h
  301. softmmu_exec.h
  302. softmmu_header.h
  303. softmmu_template.h
  304. sparc-dis.c
  305. sparc.ld
  306. sparc64.ld
  307. spice-qemu-char.c
  308. sysemu.h
  309. targphys.h
  310. tcg-runtime.c
  311. tci-dis.c
  312. tci.c
  313. test-coroutine.c
  314. test-qmp-commands.c
  315. test-qmp-input-visitor.c
  316. test-qmp-output-visitor.c
  317. thunk.c
  318. thunk.h
  319. TODO
  320. trace-events
  321. translate-all.c
  322. uboot_image.h
  323. usb-bsd.c
  324. usb-linux.c
  325. usb-redir.c
  326. usb-stub.c
  327. user-exec.c
  328. VERSION
  329. version.rc
  330. vgafont.h
  331. vl.c
  332. x86_64.ld
  333. xen-all.c
  334. xen-mapcache.c
  335. xen-mapcache.h
  336. xen-stub.c
  337. xtensa-semi.c