qemu-img: Add cache command line option

qemu-img currently writes disk images using writeback and filling
up the cache buffers which are then flushed by the kernel preventing
other processes from accessing the storage.
This is particularly bad in cluster environments where time-based
algorithms might be in place and accessing the storage within
certain timeouts is critical.
This patch adds the option to choose a cache method when writing
disk images.

Signed-off-by: Federico Simoncelli <fsimonce@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2 files changed
tree: 8c03df5b089035ff4dc1513db25ddd30ec27d344
  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. QMP/
  17. roms/
  18. scripts/
  19. slirp/
  20. sysconfigs/
  21. target-alpha/
  22. target-arm/
  23. target-cris/
  24. target-i386/
  25. target-lm32/
  26. target-m68k/
  27. target-microblaze/
  28. target-mips/
  29. target-ppc/
  30. target-s390x/
  31. target-sh4/
  32. target-sparc/
  33. target-unicore32/
  34. tcg/
  35. tests/
  36. ui/
  37. .gitignore
  38. .gitmodules
  39. a.out.h
  40. acl.c
  41. acl.h
  42. aes.c
  43. aes.h
  44. aio.c
  45. alpha-dis.c
  46. alpha.ld
  47. arch_init.c
  48. arch_init.h
  49. arm-dis.c
  50. arm-semi.c
  51. arm.ld
  52. async.c
  53. balloon.c
  54. balloon.h
  55. bitmap.c
  56. bitmap.h
  57. bitops.c
  58. bitops.h
  59. block-migration.c
  60. block-migration.h
  61. block.c
  62. block.h
  63. block_int.h
  64. blockdev.c
  65. blockdev.h
  66. bswap.h
  67. bt-host.c
  68. bt-host.h
  69. bt-vhci.c
  70. buffered_file.c
  71. buffered_file.h
  72. cache-utils.c
  73. cache-utils.h
  74. Changelog
  75. check-qdict.c
  76. check-qfloat.c
  77. check-qint.c
  78. check-qjson.c
  79. check-qlist.c
  80. check-qstring.c
  81. cmd.c
  82. cmd.h
  83. CODING_STYLE
  84. compatfd.c
  85. compatfd.h
  86. config.h
  87. configure
  88. console.c
  89. console.h
  90. COPYING
  91. COPYING.LIB
  92. cpu-all.h
  93. cpu-common.h
  94. cpu-defs.h
  95. cpu-exec.c
  96. cpus.c
  97. cpus.h
  98. cris-dis.c
  99. cursor.c
  100. cursor_hidden.xpm
  101. cursor_left_ptr.xpm
  102. cutils.c
  103. def-helper.h
  104. device_tree.c
  105. device_tree.h
  106. dis-asm.h
  107. disas.c
  108. disas.h
  109. dma-helpers.c
  110. dma.h
  111. dyngen-exec.h
  112. elf.h
  113. envlist.c
  114. envlist.h
  115. error.c
  116. error.h
  117. error_int.h
  118. exec-all.h
  119. exec.c
  120. gdbstub.c
  121. gdbstub.h
  122. gen-icount.h
  123. HACKING
  124. hmp-commands.hx
  125. host-utils.c
  126. host-utils.h
  127. hpet.h
  128. hppa-dis.c
  129. hppa.ld
  130. i386-dis.c
  131. i386.ld
  132. ia64-dis.c
  133. ia64.ld
  134. input.c
  135. iohandler.c
  136. ioport-user.c
  137. ioport.c
  138. ioport.h
  139. iorange.h
  140. iov.c
  141. iov.h
  142. json-lexer.c
  143. json-lexer.h
  144. json-parser.c
  145. json-parser.h
  146. json-streamer.c
  147. json-streamer.h
  148. kvm-all.c
  149. kvm-stub.c
  150. kvm.h
  151. libfdt_env.h
  152. LICENSE
  153. linux-aio.c
  154. m68k-dis.c
  155. m68k-semi.c
  156. m68k.ld
  157. MAINTAINERS
  158. Makefile
  159. Makefile.dis
  160. Makefile.hw
  161. Makefile.objs
  162. Makefile.target
  163. Makefile.user
  164. microblaze-dis.c
  165. migration-exec.c
  166. migration-fd.c
  167. migration-tcp.c
  168. migration-unix.c
  169. migration.c
  170. migration.h
  171. mips-dis.c
  172. mips.ld
  173. module.c
  174. module.h
  175. monitor.c
  176. monitor.h
  177. nbd.c
  178. nbd.h
  179. net.c
  180. net.h
  181. notify.c
  182. notify.h
  183. os-posix.c
  184. os-win32.c
  185. osdep.c
  186. osdep.h
  187. oslib-posix.c
  188. oslib-win32.c
  189. path.c
  190. pci-ids.txt
  191. pflib.c
  192. pflib.h
  193. poison.h
  194. posix-aio-compat.c
  195. ppc-dis.c
  196. ppc.ld
  197. ppc64.ld
  198. qbool.c
  199. qbool.h
  200. qdict-test-data.txt
  201. qdict.c
  202. qdict.h
  203. qemu-aio.h
  204. qemu-barrier.h
  205. qemu-char.c
  206. qemu-char.h
  207. qemu-common.h
  208. qemu-config.c
  209. qemu-config.h
  210. qemu-doc.texi
  211. qemu-error.c
  212. qemu-error.h
  213. qemu-img-cmds.hx
  214. qemu-img.c
  215. qemu-img.texi
  216. qemu-io.c
  217. qemu-lock.h
  218. qemu-log.h
  219. qemu-malloc.c
  220. qemu-nbd.c
  221. qemu-nbd.texi
  222. qemu-objects.h
  223. qemu-option.c
  224. qemu-option.h
  225. qemu-options.h
  226. qemu-options.hx
  227. qemu-os-posix.h
  228. qemu-os-win32.h
  229. qemu-progress.c
  230. qemu-queue.h
  231. qemu-sockets.c
  232. qemu-tech.texi
  233. qemu-thread-posix.c
  234. qemu-thread-posix.h
  235. qemu-thread-win32.c
  236. qemu-thread-win32.h
  237. qemu-thread.h
  238. qemu-timer-common.c
  239. qemu-timer.c
  240. qemu-timer.h
  241. qemu-tool.c
  242. qemu-x509.h
  243. qemu.sasl
  244. qemu_socket.h
  245. qerror.c
  246. qerror.h
  247. qfloat.c
  248. qfloat.h
  249. qint.c
  250. qint.h
  251. qjson.c
  252. qjson.h
  253. qlist.c
  254. qlist.h
  255. qmp-commands.hx
  256. qobject.h
  257. qstring.c
  258. qstring.h
  259. range.h
  260. readline.c
  261. readline.h
  262. README
  263. rules.mak
  264. rwhandler.c
  265. rwhandler.h
  266. s390-dis.c
  267. s390.ld
  268. savevm.c
  269. sh4-dis.c
  270. simpletrace.c
  271. simpletrace.h
  272. softmmu-semi.h
  273. softmmu_defs.h
  274. softmmu_exec.h
  275. softmmu_header.h
  276. softmmu_template.h
  277. sparc-dis.c
  278. sparc.ld
  279. sparc64.ld
  280. spice-qemu-char.c
  281. sysemu.h
  282. targphys.h
  283. tcg-runtime.c
  284. thunk.c
  285. thunk.h
  286. TODO
  287. trace-events
  288. translate-all.c
  289. uboot_image.h
  290. usb-bsd.c
  291. usb-linux.c
  292. usb-stub.c
  293. user-exec.c
  294. VERSION
  295. version.rc
  296. vgafont.h
  297. vl.c
  298. x86_64.ld
  299. xen-all.c
  300. xen-mapcache-stub.c
  301. xen-mapcache.c
  302. xen-mapcache.h
  303. xen-stub.c