net: notify peer about link status change

qemu makes it possible to disable link at tap which is not communicated
to the guest but causes all packets to be dropped.

This works for virtio userspace, as qemu stops giving it packets, but
not for virtio-net connected to vhost-net as that does not get notified
about this change.

Notify peer when this happens, which will then be used by the follow-up
patch to stop/start vhost-net.

Note: it might be a good idea to make peer link status match tap in this
case, so the guest gets an event and updates the carrier state. For now
stay bug for bug compatible with what we used to have in userspace.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reported-by: pradeep <psuriset@linux.vnet.ibm.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
1 file changed
tree: eacd3f0b0c238313d589a4b4bdc7112fbdfbc71e
  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. linux-user/
  12. net/
  13. pc-bios/
  14. QMP/
  15. roms/
  16. scripts/
  17. slirp/
  18. sysconfigs/
  19. target-alpha/
  20. target-arm/
  21. target-cris/
  22. target-i386/
  23. target-m68k/
  24. target-microblaze/
  25. target-mips/
  26. target-ppc/
  27. target-s390x/
  28. target-sh4/
  29. target-sparc/
  30. tcg/
  31. tests/
  32. ui/
  33. .gitignore
  34. .gitmodules
  35. a.out.h
  36. acl.c
  37. acl.h
  38. aes.c
  39. aes.h
  40. aio.c
  41. alpha-dis.c
  42. alpha.ld
  43. arch_init.c
  44. arch_init.h
  45. arm-dis.c
  46. arm-semi.c
  47. arm.ld
  48. async.c
  49. balloon.c
  50. balloon.h
  51. block-migration.c
  52. block-migration.h
  53. block.c
  54. block.h
  55. block_int.h
  56. blockdev.c
  57. blockdev.h
  58. bswap.h
  59. bt-host.c
  60. bt-host.h
  61. bt-vhci.c
  62. buffered_file.c
  63. buffered_file.h
  64. cache-utils.c
  65. cache-utils.h
  66. Changelog
  67. check-qdict.c
  68. check-qfloat.c
  69. check-qint.c
  70. check-qjson.c
  71. check-qlist.c
  72. check-qstring.c
  73. cmd.c
  74. cmd.h
  75. CODING_STYLE
  76. compatfd.c
  77. compatfd.h
  78. config.h
  79. configure
  80. console.c
  81. console.h
  82. COPYING
  83. COPYING.LIB
  84. cpu-all.h
  85. cpu-common.h
  86. cpu-defs.h
  87. cpu-exec.c
  88. cpus.c
  89. cpus.h
  90. cris-dis.c
  91. cursor.c
  92. cursor_hidden.xpm
  93. cursor_left_ptr.xpm
  94. cutils.c
  95. def-helper.h
  96. device_tree.c
  97. device_tree.h
  98. dis-asm.h
  99. disas.c
  100. disas.h
  101. dma-helpers.c
  102. dma.h
  103. dyngen-exec.h
  104. elf.h
  105. envlist.c
  106. envlist.h
  107. exec-all.h
  108. exec.c
  109. gdbstub.c
  110. gdbstub.h
  111. gen-icount.h
  112. HACKING
  113. hmp-commands.hx
  114. host-utils.c
  115. host-utils.h
  116. hpet.h
  117. hppa-dis.c
  118. hppa.ld
  119. i386-dis.c
  120. i386.ld
  121. ia64-dis.c
  122. ia64.ld
  123. input.c
  124. ioport-user.c
  125. ioport.c
  126. ioport.h
  127. iorange.h
  128. iov.c
  129. iov.h
  130. json-lexer.c
  131. json-lexer.h
  132. json-parser.c
  133. json-parser.h
  134. json-streamer.c
  135. json-streamer.h
  136. kvm-all.c
  137. kvm-stub.c
  138. kvm.h
  139. libfdt_env.h
  140. LICENSE
  141. linux-aio.c
  142. m68k-dis.c
  143. m68k-semi.c
  144. m68k.ld
  145. MAINTAINERS
  146. Makefile
  147. Makefile.dis
  148. Makefile.hw
  149. Makefile.objs
  150. Makefile.target
  151. Makefile.user
  152. microblaze-dis.c
  153. migration-exec.c
  154. migration-fd.c
  155. migration-tcp.c
  156. migration-unix.c
  157. migration.c
  158. migration.h
  159. mips-dis.c
  160. mips.ld
  161. module.c
  162. module.h
  163. monitor.c
  164. monitor.h
  165. nbd.c
  166. nbd.h
  167. net-checksum.c
  168. net.c
  169. net.h
  170. notify.c
  171. notify.h
  172. os-posix.c
  173. os-win32.c
  174. osdep.c
  175. osdep.h
  176. oslib-posix.c
  177. oslib-win32.c
  178. path.c
  179. pci-ids.txt
  180. pflib.c
  181. pflib.h
  182. poison.h
  183. posix-aio-compat.c
  184. ppc-dis.c
  185. ppc.ld
  186. ppc64.ld
  187. qbool.c
  188. qbool.h
  189. qdict-test-data.txt
  190. qdict.c
  191. qdict.h
  192. qemu-aio.h
  193. qemu-barrier.h
  194. qemu-char.c
  195. qemu-char.h
  196. qemu-common.h
  197. qemu-config.c
  198. qemu-config.h
  199. qemu-doc.texi
  200. qemu-error.c
  201. qemu-error.h
  202. qemu-img-cmds.hx
  203. qemu-img.c
  204. qemu-img.texi
  205. qemu-io.c
  206. qemu-lock.h
  207. qemu-log.h
  208. qemu-malloc.c
  209. qemu-nbd.c
  210. qemu-nbd.texi
  211. qemu-objects.h
  212. qemu-option.c
  213. qemu-option.h
  214. qemu-options.h
  215. qemu-options.hx
  216. qemu-os-posix.h
  217. qemu-os-win32.h
  218. qemu-queue.h
  219. qemu-sockets.c
  220. qemu-tech.texi
  221. qemu-thread.c
  222. qemu-thread.h
  223. qemu-timer-common.c
  224. qemu-timer.c
  225. qemu-timer.h
  226. qemu-tool.c
  227. qemu-x509.h
  228. qemu.sasl
  229. qemu_socket.h
  230. qerror.c
  231. qerror.h
  232. qfloat.c
  233. qfloat.h
  234. qint.c
  235. qint.h
  236. qjson.c
  237. qjson.h
  238. qlist.c
  239. qlist.h
  240. qmp-commands.hx
  241. qobject.h
  242. qstring.c
  243. qstring.h
  244. range.h
  245. readline.c
  246. readline.h
  247. README
  248. rules.mak
  249. rwhandler.c
  250. rwhandler.h
  251. s390-dis.c
  252. s390.ld
  253. savevm.c
  254. sh4-dis.c
  255. simpletrace.c
  256. simpletrace.h
  257. softmmu-semi.h
  258. softmmu_defs.h
  259. softmmu_exec.h
  260. softmmu_header.h
  261. softmmu_template.h
  262. sparc-dis.c
  263. sparc.ld
  264. sparc64.ld
  265. spice-qemu-char.c
  266. sysemu.h
  267. targphys.h
  268. tcg-runtime.c
  269. thunk.c
  270. thunk.h
  271. TODO
  272. trace-events
  273. translate-all.c
  274. uboot_image.h
  275. usb-bsd.c
  276. usb-linux.c
  277. usb-stub.c
  278. VERSION
  279. version.rc
  280. vgafont.h
  281. vl.c
  282. x86_64.ld