[2/2] Update man page for allocator_hint property.

Commit Message

Goffredo Baroncelli Dec. 17, 2021, 6:47 p.m. UTC

From: Goffredo Baroncelli <[e-mail]>

Update the man page of the btrfs property subcommand to show the use
of the device property "allocation_hint".

Signed-off-by: Goffredo Baroncelli <[e-mail]>
---
 Documentation/btrfs-property.asciidoc | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

Patch

diff --git a/Documentation/btrfs-property.asciidoc b/Documentation/btrfs-property.asciidoc
index b32d000e..d9e9c4b9 100644
--- a/Documentation/btrfs-property.asciidoc
+++ b/Documentation/btrfs-property.asciidoc
@@ -49,6 +49,23 @@  device as object. For a mounted filesystem, specify a mount point.
 compression::::
 compression algorithm set for an inode, possible values: 'lzo', 'zlib', 'zstd'.
 To disable compression use "" (empty string), 'no' or 'none'.
+allocation_hint::::
+a device property that instructs how and when the allocator should use a
+block device.
+Possible values are:
+- 'PREFERRED_METADATA': the device has an higher priority when a new metadata
+chunk is allocated. Data chunk is allowed only if there is no other possibility.
+- 'METADATA_ONLY': the device is used only for metadata chunk.
+Data chunk is never allowed.
+- 'PREFERRED_DATA' (default): the device has an higher priority when a new data
+chunk is allocated. Metadata chunk is allowed only if there is no other
+possibility.
+- 'DATA_ONLY': the device is used only for data chunk.
+Metadata chunk is never allowed.
+ ::::
+The default is 'PREFERRED_DATA'; if all the disks have this setting the
+allocator uses all of them with the same priority.
+
 
 *list* [-t <type>] <object>::
 Lists available properties with their descriptions for the given object.