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-rw-r--r--qemu-nbd.texi34
1 files changed, 22 insertions, 12 deletions
diff --git a/qemu-nbd.texi b/qemu-nbd.texi
index 26cc985039..5331d697c4 100644
--- a/qemu-nbd.texi
+++ b/qemu-nbd.texi
@@ -1,19 +1,23 @@
@example
@c man begin SYNOPSIS
-usage: qemu-nbd [OPTION]... @var{filename}
+@command{qemu-nbd} [OPTION]... @var{filename}
+
+@command{qemu-nbd} @option{-d} @var{dev}
@c man end
@end example
@c man begin DESCRIPTION
-Export QEMU disk image using NBD protocol.
+Export a QEMU disk image using the NBD protocol.
@c man end
@c man begin OPTIONS
+@var{filename} is a disk image filename.
+
+@var{dev} is an NBD device.
+
@table @option
-@item @var{filename}
-is a disk image filename
@item -p, --port=@var{port}
port to listen on (default @samp{10809})
@item -o, --offset=@var{offset}
@@ -22,8 +26,9 @@ offset into the image
interface to bind to (default @samp{0.0.0.0})
@item -k, --socket=@var{path}
Use a unix socket with path @var{path}
-@item -f, --format=@var{format}
-Set image format as @var{format}
+@item -f, --format=@var{fmt}
+force the use of the block driver for format @var{fmt} instead of
+auto-detecting
@item -r, --read-only
export read-only
@item -P, --partition=@var{num}
@@ -44,17 +49,22 @@ the emulator's @code{-drive cache=...} option for allowed values.
choose asynchronous I/O mode between @samp{threads} (the default)
and @samp{native} (Linux only).
@item --discard=@var{discard}
-toggles whether @dfn{discard} (also known as @dfn{trim} or @dfn{unmap})
-requests are ignored or passed to the filesystem. The default is no
-(@samp{--discard=ignore}).
+controls whether @dfn{discard} (also known as @dfn{trim} or @dfn{unmap})
+requests are ignored or passed to the filesystem. @var{discard} is one of
+@samp{ignore} (or @samp{off}), @samp{unmap} (or @samp{on}). The default is
+@samp{ignore}.
+@item --detect-zeroes=@var{detect-zeroes}
+enables the automatic conversion of plain zero writes by the OS to
+driver-specific optimized zero write commands. @var{detect-zeroes} is one of
+@samp{off}, @samp{on} or @samp{unmap}. @samp{unmap}
+converts a zero write to an unmap operation and can only be used if
+@var{discard} is set to @samp{unmap}. The default is @samp{off}.
@item -c, --connect=@var{dev}
connect @var{filename} to NBD device @var{dev}
@item -d, --disconnect
disconnect the specified device
@item -e, --shared=@var{num}
device can be shared by @var{num} clients (default @samp{1})
-@item -f, --format=@var{fmt}
-force block driver for format @var{fmt} instead of auto-detecting
@item -t, --persistent
don't exit on the last connection
@item -v, --verbose
@@ -79,7 +89,7 @@ warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
@c man end
@c man begin SEEALSO
-qemu-img(1)
+qemu(1), qemu-img(1)
@c man end
@end ignore