diff options
author | Kevin Wolf <kwolf@redhat.com> | 2021-01-18 13:34:47 +0100 |
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committer | Kevin Wolf <kwolf@redhat.com> | 2021-01-27 20:45:20 +0100 |
commit | 86b1cf322789b79c8ace977430ac6a443d491cc0 (patch) | |
tree | baac83ce91c3f7ea7c7ec61fa9249b205459b387 /qemu-img-cmds.hx | |
parent | bf159f0bdc7b8e7aa8342dedb3829ca744c1b612 (diff) |
block: Separate blk_is_writable() and blk_supports_write_perm()
Currently, blk_is_read_only() tells whether a given BlockBackend can
only be used in read-only mode because its root node is read-only. Some
callers actually try to answer a slightly different question: Is the
BlockBackend configured to be writable, by taking write permissions on
the root node?
This can differ, for example, for CD-ROM devices which don't take write
permissions, but may be backed by a writable image file. scsi-cd allows
write requests to the drive if blk_is_read_only() returns false.
However, the write request will immediately run into an assertion
failure because the write permission is missing.
This patch introduces separate functions for both questions.
blk_supports_write_perm() answers the question whether the block
node/image file can support writable devices, whereas blk_is_writable()
tells whether the BlockBackend is currently configured to be writable.
All calls of blk_is_read_only() are converted to one of the two new
functions.
Fixes: https://bugs.launchpad.net/bugs/1906693
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20210118123448.307825-2-kwolf@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Diffstat (limited to 'qemu-img-cmds.hx')
0 files changed, 0 insertions, 0 deletions