[thirdparty/xfsprogs-dev.git] / man / man8 / xfs_bmap.8

.TH xfs_bmap 8
.SH NAME
xfs_bmap \- print block mapping for an XFS file
.SH SYNOPSIS
.B xfs_bmap
[
.B \-adelpv
] [
.B \-n
.I num_extents
]
.I file
.br
.B xfs_bmap \-V
.SH DESCRIPTION
.B xfs_bmap
prints the map of disk blocks used by files in an XFS filesystem.
The map lists each
.I extent
used by the file, as well as regions
in the file that do not have any corresponding blocks (holes).
Each line of the listings takes the following form:
.PP
.RS
.IR extent ": [" startoffset .. endoffset "]: " startblock .. endblock
.RE
.PP
Holes are marked by replacing the
.IR startblock .. endblock " with " hole .
All the file offsets and disk blocks are in units of 512-byte blocks,
no matter what the filesystem's block size is.
.PP
.SH OPTIONS
.TP
.B \-a
If this option is specified, information about the file's
attribute fork is printed instead of the default data fork.
.TP
.B \-c
If this option is specified, information about the file's
copy on write fork is printed instead of the default data fork.
.TP
.B \-d
If portions of the file have been migrated offline by
a DMAPI application, a DMAPI read event will be generated to
bring those portions back online before the disk block map is
printed.  However if the
.B \-d
option is used, no DMAPI read event will be generated for a
DMAPI file and offline portions will be reported as holes.
.TP
.B \-e
If this option is used,
.B xfs_bmap
obtains all delayed allocation extents, and does not flush dirty pages
to disk before querying extent data. With the
.B \-v
option, the
.I flags
column will show which extents have not yet been allocated.
.TP
.B \-l
If this option is used, then
.IP
.RS 1.2i
.RI < nblocks ">  blocks"
.RE
.IP
will be appended to each line.
.I nblocks
is the length of the extent described on the line in units of 512-byte blocks.
.IP
This flag has no effect if the
.B \-v
option is used.
.TP
.BI \-n " num_extents"
If this option is given,
.B xfs_bmap
will display at most
.I num_extents
extents. In the absence of
.BR \-n ", " xfs_bmap
will display all extents in the file.
.TP
.B \-p
If this option is used,
.B xfs_bmap
obtains all unwritten (preallocated) extents that do not contain written
data. With the
.B \-v
option, the
.I flags
column will show which extents are preallocated/unwritten.
.TP
.B \-v
Shows verbose information. When this flag is specified, additional AG
specific information is appended to each line in the following form:
.IP
.RS 1.2i
.IR agno " (" startagoffset .. endagoffset ") " nblocks " " flags
.RE
.IP
A second
.B \-v
option will print out the
.I flags
legend.
.TP
.B \-V
Prints the version number and exits.
.SH SEE ALSO
.BR xfs_fsr (8),
.BR xfs (5).
Commit	Line	Data
2bd0ea18 NS	1	.TH xfs_bmap 8
	2	.SH NAME
	3	xfs_bmap \- print block mapping for an XFS file
	4	.SH SYNOPSIS
753bf054 BN	5	.B xfs_bmap
753bf054 BN	6	[
54806785	7	.B \-adelpv
753bf054 BN	8	] [
	9	.B \-n
	10	.I num_extents
	11	]
	12	.I file
eaa6a2bf ES	13	.br
eaa6a2bf ES	14	.B xfs_bmap \-V
2bd0ea18	15	.SH DESCRIPTION
753bf054	16	.B xfs_bmap
2bd0ea18	17	prints the map of disk blocks used by files in an XFS filesystem.
753bf054 BN	18	The map lists each
	19	.I extent
	20	used by the file, as well as regions
	21	in the file that do not have any corresponding blocks (holes).
2bd0ea18	22	Each line of the listings takes the following form:
753bf054 BN	23	.PP
	24	.RS
	25	.IR extent ": [" startoffset .. endoffset "]: " startblock .. endblock
	26	.RE
	27	.PP
	28	Holes are marked by replacing the
	29	.IR startblock .. endblock " with " hole .
2bd0ea18 NS	30	All the file offsets and disk blocks are in units of 512-byte blocks,
	31	no matter what the filesystem's block size is.
	32	.PP
753bf054 BN	33	.SH OPTIONS
	34	.TP
	35	.B \-a
	36	If this option is specified, information about the file's
	37	attribute fork is printed instead of the default data fork.
	38	.TP
7536ce44 DW	39	.B \-c
	40	If this option is specified, information about the file's
	41	copy on write fork is printed instead of the default data fork.
	42	.TP
753bf054	43	.B \-d
2bd0ea18 NS	44	If portions of the file have been migrated offline by
	45	a DMAPI application, a DMAPI read event will be generated to
	46	bring those portions back online before the disk block map is
753bf054 BN	47	printed. However if the
	48	.B \-d
	49	option is used, no DMAPI read event will be generated for a
	50	DMAPI file and offline portions will be reported as holes.
	51	.TP
7536ce44 DW	52	.B \-e
	53	If this option is used,
	54	.B xfs_bmap
	55	obtains all delayed allocation extents, and does not flush dirty pages
	56	to disk before querying extent data. With the
	57	.B \-v
	58	option, the
	59	.I flags
	60	column will show which extents have not yet been allocated.
	61	.TP
753bf054 BN	62	.B \-l
	63	If this option is used, then
	64	.IP
	65	.RS 1.2i
	66	.RI < nblocks "> blocks"
	67	.RE
	68	.IP
	69	will be appended to each line.
	70	.I nblocks
	71	is the length of the extent described on the line in units of 512-byte blocks.
	72	.IP
	73	This flag has no effect if the
	74	.B \-v
	75	option is used.
	76	.TP
	77	.BI \-n " num_extents"
	78	If this option is given,
	79	.B xfs_bmap
fa9f6f13	80	will display at most
753bf054 BN	81	.I num_extents
	82	extents. In the absence of
	83	.BR \-n ", " xfs_bmap
fa9f6f13	84	will display all extents in the file.
753bf054 BN	85	.TP
	86	.B \-p
	87	If this option is used,
	88	.B xfs_bmap
	89	obtains all unwritten (preallocated) extents that do not contain written
	90	data. With the
	91	.B \-v
	92	option, the
	93	.I flags
	94	column will show which extents are preallocated/unwritten.
	95	.TP
	96	.B \-v
	97	Shows verbose information. When this flag is specified, additional AG
	98	specific information is appended to each line in the following form:
	99	.IP
	100	.RS 1.2i
	101	.IR agno " (" startagoffset .. endagoffset ") " nblocks " " flags
	102	.RE
	103	.IP
	104	A second
	105	.B \-v
	106	option will print out the
	107	.I flags
	108	legend.
eaa6a2bf ES	109	.TP
	110	.B \-V
	111	Prints the version number and exits.
2bd0ea18	112	.SH SEE ALSO
753bf054 BN	113	.BR xfs_fsr (8),
753bf054 BN	114	.BR xfs (5).