btrfs-progs: docs: convert btrfs-receive to rst

Signed-off-by: David Sterba <dsterba@suse.com>

Documentation/btrfs-receive.rst

@@ -0,0 +1,117 @@
+btrfs-receive(8)
+================
+
+SYNOPSIS
+--------
+
+**btrfs receive** [options] <path>
+
+or
+
+**btrfs receive** --dump [options]
+
+DESCRIPTION
+-----------
+
+Receive a stream of changes and replicate one or more subvolumes that were
+previously generated by **btrfs send**. The received subvolumes are stored to
+*path*, unless *--dump* option is given.
+
+If *--dump* option is specified, **btrfs receive** will only do the validation of
+the stream, and print the stream metadata, one operation per line.
+
+**btrfs receive** will fail in the following cases:
+
+1. receiving subvolume already exists
+
+2. previously received subvolume has been changed after it was received
+
+3. default subvolume has changed or you didn't mount the filesystem at the toplevel subvolume
+
+A subvolume is made read-only after the receiving process finishes successfully (see BUGS below).
+
+``Options``
+
+-f <FILE>
+        read the stream from *FILE* instead of stdin,
+
+-C|--chroot
+        confine the process to *path* using ``chroot(1)``
+
+-e
+        terminate after receiving an *end cmd* marker in the stream.
+
+        Without this option the receiver side terminates only in case
+        of an error on end of file.
+
+-E|--max-errors <NERR>
+        terminate as soon as NERR errors occur while stream processing commands from
+        the stream
+
+        Default value is 1. A value of 0 means no limit.
+
+-m <ROOTMOUNT>
+        the root mount point of the destination filesystem
+
+        By default the mountpoint is searched in */proc/self/mounts*.
+        If */proc* is not accessible, eg. in a chroot environment, use this option to
+        tell us where this filesystem is mounted.
+
+--dump
+        dump the stream metadata, one line per operation
+
+        Does not require the *path* parameter. The filesystem remains unchanged.
+
+-q|--quiet
+        (deprecated) alias for global *-q* option
+
+-v
+        (deprecated) alias for global *-v* option
+
+``Global options``
+
+-v|--verbose
+        increase verbosity about performed actions, print details about each operation
+
+-q|--quiet
+        suppress all messages except errors
+
+BUGS
+----
+
+**btrfs receive** sets the subvolume read-only after it completes
+successfully.  However, while the receive is in progress, users who have
+write access to files or directories in the receiving *path* can add,
+remove, or modify files, in which case the resulting read-only subvolume
+will not be an exact copy of the sent subvolume.
+
+If the intention is to create an exact copy, the receiving *path*
+should be protected from access by users until the receive operation
+has completed and the subvolume is set to read-only.
+
+Additionally, receive does not currently do a very good job of validating
+that an incremental send stream actually makes sense, and it is thus
+possible for a specially crafted send stream to create a subvolume with
+reflinks to arbitrary files in the same filesystem.  Because of this,
+users are advised to not use *btrfs receive* on send streams from
+untrusted sources, and to protect trusted streams when sending them
+across untrusted networks.
+
+EXIT STATUS
+-----------
+
+**btrfs receive** returns a zero exit status if it succeeds. Non zero is
+returned in case of failure.
+
+AVAILABILITY
+------------
+
+**btrfs** is part of btrfs-progs.
+Please refer to the btrfs wiki http://btrfs.wiki.kernel.org for
+further details.
+
+SEE ALSO
+--------
+
+``mkfs.btrfs(8)``,
+``btrfs-send(8)``

Documentation/conf.py

@@ -48,4 +48,5 @@ man_pages = [
     ('btrfs-restore', 'btrfs-restore', 'try to restore files from a damaged filesystem image', '', 8),
     ('btrfs-rescue', 'btrfs-rescue', 'recover a damaged btrfs filesystem', '', 8),
     ('btrfs-replace', 'btrfs-replace', 'replace devices managed by btrfs with other device', '', 8),
+    ('btrfs-receive', 'btrfs-receive', 'receive subvolumes from send stream', '', 8),
 ]

Documentation/man-index.rst

@@ -6,6 +6,7 @@ Manual pages
 .. toctree::
    :maxdepth: 1
 
+   btrfs-receive
    btrfs-replace
    btrfs-rescue
    btrfs-restore