1BMAPTOOL(1) User Commands BMAPTOOL(1)
2
6 bmaptool - create block map (bmap) for a file or copy a file using bmap
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10 bmaptool [--help] [--version] [--quiet] [--debug] <command> [<options>]
11 <args>
12
15 Bmaptool is a generic tool for creating the block map (bmap) for a file
16 and copying files using the block map. The idea is that large files,
17 like raw system image files, can be copied or flashed a lot faster with
18 bmaptool than with traditional tools, like "dd" or "cp".
19 Bmaptool supports 2 commands:
22 1. copy - copy a file to another file using bmap or flash an image to
23 a block device
24 2. create - create a bmap for a file
25 Please, find full documentation for the project online.
28
31 --version
32 Print bmaptool version and exit.
33 -h, --help
36 Print short help text and exit.
37 -q, --quiet
40 Be quiet, do not print extra information.
41 -d, --debug
44 Print debugging messages.
45
48 copy [options] IMAGE DEST
49 Copy file IMAGE to the destination regular file or block device DEST
50 using bmap. IMAGE may either be a local path or an URL. DEST may
51 either be a regular file or a block device (only local).
52 Unless the bmap file is explicitly specified with the "--bmap"
55 option, bmaptool automatically discovers it by looking for a file
56 with the same basename as IMAGE but with the ".bmap" extension. The
57 bmap file is only looked for in IMAGE's directory (or base URL, in
58 case IMAGE was specified as an URL). If the bmap file is not found,
59 bmaptool fails. To copy without bmap, use the "--nobmap" option.
60 Both IMAGE and the bmap file may be specified as an URL (http://,
63 ftp://, https://, file://, ssh://). In order to make bmaptool use a
64 proxy server, please, specify the proxy using the standard
65 "$http_proxy", "$https_proxy", "$ftp_proxy" or "$no_proxy" environ‐
66 ment variables.
67 If the server requires authentication, user name and password may be
70 specified in the URL, for example "https://user:pass‐
71 word@my.server.org/image.raw.bz2", or "ssh://user:pass‐
72 word@host:path/to/image.raw".
73 IMAGE may be compressed, in which case bmaptool decompresses it on-
76 the-fly. The compression type is detected by the file extension and
77 the following extensions are supported:
78 1. ".gz", ".gzip", ".tar.gz" and ".tgz" for files and tar ar‐
80 chives compressed with "gzip" program
81 2. ".bz2", "tar.bz2", ".tbz2", ".tbz", and ".tb2" for files and
82 tar archives compressed with "bzip2" program
83 3. ".xz", ".tar.xz", ".txz" for files and tar archives compressed
84 with "xz" program
85 4. ".lzo", "tar.lzo", ".tzo" for files and tar archives com‐
86 pressed with "lzo" program
87 4. ".lz4", "tar.lz4", ".tlz4" for files and tar archives com‐
88 pressed with "lz4" program
89 IMAGE files with other extensions are assumed to be uncompressed.
92 Note, bmaptool uses "pbzip2" and "pigz" programs for decompressing
93 bzip2 and gzip archives faster, unless they are not available, in
94 which case if falls-back to using "bzip2" and "gzip".
95 If DEST is a block device node (e.g., "/dev/sdg"), bmaptool opens it
98 in exclusive mode. This means that it will fail if any other process
99 has IMAGE block device node opened. This also means that no other
100 processes will be able to open IMAGE until bmaptool finishes the
101 copying. Please, see semantics of the "O_EXCL" flag of the "open()"
102 syscall.
103 The bmap file typically contains SHA-256 checksum for itself as well
106 as SHA-256 checksum for all the mapped data regions, which makes it
107 possible to guarantee data integrity. bmaptool verifies the checksums
108 and exits with an error in case of a mismatch. Checksum verification
109 can be disabled using the "--no-verify" option. bmaptool does not
110 verify that unampped areas contain only zeroes, because these areas
111 are anyway dropped and are not used for anything.
112 The bmap file may be signed with OpenPGP (gpg). The signature may be
115 either detached (a separate file) or "built into" the bmap file (so
116 called "clearsign" signature).
117 The detached signature can be specified with the "--bmap-sig" option,
120 otherwise bmaptool tries to automatically discover it by looking for
121 a file with the same basename as the bmap file but with the ".asc" or
122 ".sig" extension. This is very similar to the bmap file auto-discov‐
123 ery. So if a ".asc" or ".sig" file exists, bmaptool will verify the
124 signature.
125 The clearsign signature is part of the bmap file and bmaptool auto‐
128 matically detected and verifies it.
129 If the signature is bad, bmaptool exits with an error. Bmap file sig‐
132 nature verification can be disabled using the "--no-sig-verify"
133 option.
134 OPTIONS
136 -h, --help
137 Print short help text about the "copy" command and exit.
138 --bmap BMAP
141 Use bmap file "BMAP" for copying. If this option is not speci‐
142 fied, bmaptool tries to automatically discover the bmap file.
143 --bmap-sig SIG
146 Use a detached OpenPGP signature file "SIG" for verifying the
147 bmap file integrity and publisher. If this option is not speci‐
148 fied, bmaptool tries to automatically discover the signature
149 file.
150 --nobmap
153 Disable automatic bmap file discovery and force flashing entire
154 IMAGE without bmap.
155 --no-verify
158 Do not verify data checksums when copying (not recommended). The
159 checksums are stored in the bmap file, and normally bmaptool ver‐
160 ifies that the data in IMAGE matches the checksums.
161 --no-sig-verify
164 Do not verify the OpenPGP bmap file signature (not recommended).
165 EXAMPLES
167 bmaptool copy image.raw.bz2 /dev/sdg
168 Copy bz2-compressed local file "image.raw.bz2" to block device
169 "/dev/sdg". The image file is uncompressed on-the-fly. The bmap
170 file is discovered automatically. The OpenPGP signature is
171 detected/discovered automatically too.
172 bmaptool copy http://my-server.com/files/image.raw.bz2
174 $HOME/tmp/file
175 Copy bz2-compressed remote "image.raw.bz2" to regular file
176 "$HOME/tmp/file". The image file is uncompressed on-the-fly.
177 The bmap file is discovered automatically. The OpenPGP signa‐
178 ture is detected/discovered automatically too.
179 bmaptool copy --bmap image.bmap --bmap-sig image.bmap.asc
181 image.raw /dev/sdg
182 Copy non-compressed local file "image.raw" to block device
183 "/dev/sdg" using bmap file "image.bmap". Verify the bmap file
184 signature using a detached OpenPGP signature from
185 "imag.bmap.asc".
186 create [options] IMAGE
189 Generate bmap for a regular file IMAGE. Internally, this command uses
190 the Linux "FIEMAP" ioctl to find out which IMAGE blocks are mapped.
191 However, if "FIEMAP" is not supported, the "SEEK_HOLE" feature of the
192 "lseek" system call is used instead. By default, the resulting bmap
193 file is printed to stdout, unless the "--output" option is used.
194 The IMAGE file is always synchronized before the block map is gener‐
197 ated. And it is important to make sure that the IMAGE file is not modi‐
198 fied when the bmap file is being generated, and after the bmap file has
199 been generated. Otherwise the bmap file becomes invalid and checksum
200 verification will fail.
201 The image file can further be signed using OpenPGP.
204 OPTIONS
206 -h, --help
207 Print short help text about the "create" command and exit.
208 -o, --output OUTPUT
211 Save the generated bmap in the OUTPUT file (by default the bmap
212 is printed to stdout).
213 --no-checksum
216 Generate a bmap file without SHA1 checksums (not recommended).
217 EXAMPLES
219 bmaptool create image.raw
220 Generate bmap for the "image.raw" file and print it to stdout.
221 bmaptool create -o image.bmap image.raw
223 Generate bmap for the "image.raw" file and save it in
224 "image.bmap".
225
228 Artem Bityutskiy <artem.bityutskiy@linux.intel.com>.
229
232 Please, report bugs to Artem Bityutskiy <artem.bityut‐
233 skiy@linux.intel.com> or to the bmap-tools mailing list <bmap-
234 tools@lists.infradead.org>.
235bmap-tools 3.2 February 2014 BMAPTOOL(1)