Document the new copy-on-write extent size fields and inode flags available in struct fsxattr. Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> --- man/man3/xfsctl.3 | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) diff --git a/man/man3/xfsctl.3 b/man/man3/xfsctl.3 index ef6c992..77506aa 100644 --- a/man/man3/xfsctl.3 +++ b/man/man3/xfsctl.3 @@ -150,6 +150,15 @@ value returned indicates that a preferred extent size was previously set on the file, a .B fsx_extsize of zero indicates that the defaults for that filesystem will be used. +A +.B fsx_cowextsize +value returned indicates that a preferred copy on write extent size was +previously set on the file, whereas a +.B fsx_cowextsize +of zero indicates that the defaults for that filesystem will be used. +The current default for +.B fsx_cowextsize +is 128 blocks. Currently the meaningful bits for the .B fsx_xflags field are: @@ -240,6 +249,15 @@ and .BR XFS_XFLAG_DAX set at the same time, that is to say that DAX files cannot share blocks. .TP +.SM "Bit 17 (0x20000) \- XFS_XFLAG_COWEXTSIZE" +Copy on Write Extent size bit - if a CoW extent size value is set on the file, +the allocator will allocate extents for staging a copy on write operation +in multiples of the set size for this file (see +.B XFS_IOC_FSSETXATTR +below). +If the CoW extent size is set on a directory, then new file and directories +created in the directory will inherit the parent's CoW extent size value. +.TP .SM "Bit 31 (0x80000000) \- XFS_XFLAG_HASATTR" The file has extended attributes associated with it. .RE @@ -261,7 +279,8 @@ The final argument points to a variable of type .BR "struct fsxattr" , but only the following fields are used in this call: .BR fsx_xflags , -.B fsx_extsize +.BR fsx_extsize , +.BR fsx_cowextsize , and .BR fsx_projid . The @@ -271,6 +290,9 @@ when the file is empty, except in the case of a directory where the extent size can be set at any time (this value is only used for regular file allocations, so should only be set on a directory in conjunction with the XFS_XFLAG_EXTSZINHERIT flag). +The copy on write extent size, +.BR fsx_cowextsize , +can be set at any time. .TP .B XFS_IOC_GETBMAP _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
