block: Default .bdrv_child_perm() for format drivers

Almost all format drivers have the same characteristics as far as
permissions are concerned: They have one or more children for storing
their own data and, more importantly, metadata (can be written to and
grow even without external write requests, must be protected against
other writers and present consistent data) and optionally a backing file
(this is just data, so like for a filter, it only depends on what the
parent nodes need).

This provides a default implementation that can be shared by most of
our format drivers.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Acked-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
2 files changed
tree: 15a63fbf16840c39c0b921308e6b52dce757ee11
  1. audio/
  2. backends/
  3. block/
  4. bsd-user/
  5. chardev/
  6. contrib/
  7. crypto/
  8. default-configs/
  9. disas/
  10. docs/
  11. fpu/
  12. fsdev/
  13. gdb-xml/
  14. hw/
  15. include/
  16. io/
  17. libdecnumber/
  18. linux-headers/
  19. linux-user/
  20. migration/
  21. nbd/
  22. net/
  23. pc-bios/
  24. po/
  25. qapi/
  26. qga/
  27. qobject/
  28. qom/
  29. replay/
  30. roms/
  31. scripts/
  32. slirp/
  33. stubs/
  34. target/
  35. tcg/
  36. tests/
  37. trace/
  38. ui/
  39. util/
  40. .dir-locals.el
  41. .exrc
  42. .gitignore
  43. .gitmodules
  44. .mailmap
  45. .shippable.yml
  46. .travis.yml
  47. accel.c
  48. arch_init.c
  49. atomic_template.h
  50. balloon.c
  51. block.c
  52. blockdev-nbd.c
  53. blockdev.c
  54. blockjob.c
  55. bootdevice.c
  56. bt-host.c
  57. bt-vhci.c
  58. Changelog
  59. CODING_STYLE
  60. configure
  61. COPYING
  62. COPYING.LIB
  63. cpu-exec-common.c
  64. cpu-exec.c
  65. cpus-common.c
  66. cpus.c
  67. cputlb.c
  68. device-hotplug.c
  69. device_tree.c
  70. disas.c
  71. dma-helpers.c
  72. dump.c
  73. exec.c
  74. gdbstub.c
  75. HACKING
  76. hax-stub.c
  77. hmp-commands-info.hx
  78. hmp-commands.hx
  79. hmp.c
  80. hmp.h
  81. ioport.c
  82. iothread.c
  83. kvm-all.c
  84. kvm-stub.c
  85. LICENSE
  86. MAINTAINERS
  87. Makefile
  88. Makefile.objs
  89. Makefile.target
  90. memory.c
  91. memory_ldst.inc.c
  92. memory_mapping.c
  93. module-common.c
  94. monitor.c
  95. numa.c
  96. os-posix.c
  97. os-win32.c
  98. page_cache.c
  99. qapi-schema.json
  100. qdev-monitor.c
  101. qdict-test-data.txt
  102. qemu-bridge-helper.c
  103. qemu-doc.texi
  104. qemu-ga.texi
  105. qemu-img-cmds.hx
  106. qemu-img.c
  107. qemu-img.texi
  108. qemu-io-cmds.c
  109. qemu-io.c
  110. qemu-nbd.c
  111. qemu-nbd.texi
  112. qemu-option-trace.texi
  113. qemu-options-wrapper.h
  114. qemu-options.h
  115. qemu-options.hx
  116. qemu-seccomp.c
  117. qemu-tech.texi
  118. qemu.nsi
  119. qemu.sasl
  120. qmp.c
  121. qtest.c
  122. README
  123. replication.c
  124. replication.h
  125. rules.mak
  126. softmmu_template.h
  127. spice-qemu-char.c
  128. tcg-runtime.c
  129. tci.c
  130. thunk.c
  131. tpm.c
  132. trace-events
  133. translate-all.c
  134. translate-all.h
  135. translate-common.c
  136. user-exec-stub.c
  137. user-exec.c
  138. VERSION
  139. version.rc
  140. vl.c
  141. xen-common-stub.c
  142. xen-common.c
  143. xen-hvm-stub.c
  144. xen-hvm.c
  145. xen-mapcache.c