/On 8/28/23 23:56, Joshua Watt wrote:
Adds initial documentation for the gpt command
Signed-off-by: Joshua Watt JPEWhacker@gmail.com
doc/usage/cmd/gpt.rst | 184 ++++++++++++++++++++++++++++++++++++++++++ doc/usage/index.rst | 1 + 2 files changed, 185 insertions(+) create mode 100644 doc/usage/cmd/gpt.rst
diff --git a/doc/usage/cmd/gpt.rst b/doc/usage/cmd/gpt.rst new file mode 100644 index 0000000000..6387c8116f --- /dev/null +++ b/doc/usage/cmd/gpt.rst @@ -0,0 +1,184 @@ +.. SPDX-License-Identifier: GPL-2.0+
+gpt command +===========
+Synopsis +--------
+::
- gpt enumerate <interface> <dev>
- gpt guid <interface> <dev> [<varname>]
- gpt read <interface> <dev> [<varname>]
- gpt rename <interface> <dev> <part> <name>
- gpt repair <interface> <dev>
- gpt setenv <interface> <dev> <partition name>
- gpt swap <interface> <dev> <name1> <name2>
- gpt verify <interface> <dev> [<partition string>]
- gpt write <interface> <dev> <partition string>
+Description +-----------
+The gpt command lets users read, create, modify, or verify the GPT (GUID +Partition Table) partition layout.
+Common arguments:
+interface
- interface for accessing the block device (mmc, sata, scsi, usb, ....)
+dev
- device number
+partition string
- Describes the GPT partition layout for a disk. The syntax is similar to
- the one used by the :doc:`mbr command <mbr>` command. The string contains
- one or more partition descriptors, each separated by a ";". Each descriptor
- contains one or more fields, with each field separated by a ",". Fields are
- either of the form "key=value" to set a specific value, or simple "flag" to
- set a boolean flag
- The first descriptor can optionally be used to describe parameters for the
- whole disk with the following fields:
- uuid_disk=UUID - Set the UUID for the disk
- Partition descriptors can have the following fields:
- name=<NAME> - The partition name, required
- start=<BYTES> - The partition start offset in bytes, required
The code has this comment: "start address is optional".
- size=<BYTES> - The partition size in bytes or "-" to expand it to the whole free area
This filed is mandatory.
- bootable - Set the legacy bootable flag
This field is optional
- uuid=<UUID> - The partition UUID, optional if CONFIG_RANDOM_UUID=y is enabled
- type=<UUID> - The partition type GUID, requires CONFIG_PARTITION_TYPE_GUID=y
This field is optional
Thanks for all the updates. Looks much neater now.
The sequence expected in set_gpt_info() is:
uuid (optional if CONFIG_RANDOM_UUID=y), type (optional, only usable for CONFIG_PARTITION_TYPE_GUID=y), name (mandatory), size (mandatory), start (optional), bootable (optional).
From the description above it is not clear that:
* semicolons are used to separate partitions * the exact sequence of fields must be kept * commas are used to separate fields * no extra white-space is allowed.
- If 'uuid' is not specified, but CONFIG_RANDOM_UUID is enabled, a random UUID
- will be generated for the partition
+gpt enumerate +~~~~~~~~~~~~~
+Sets the variable 'gpt_partition_list' to be a list of all the partition names +on the device.
+gpt guid +~~~~~~~~
+Report the GUID of a disk. If 'varname' is specified, the command will set the +variable to the GUID, otherwise it will be printed out.
+gpt read +~~~~~~~~
+Prints the current state of the GPT partition table. If 'varname' is specified, +the variable will be filled with a partition string in the same format as a +'<partition string>', suitable for passing to other 'gpt' commands. If the +argument is omitted, a human readable description is printed out. +CONFIG_CMD_GPT_RENAME=y is required.
+gpt rename +~~~~~~~~~~
+Renames all partitions named 'part' to be 'name'. CONFIG_CMD_GPT_RENAME=y is +required.
+gpt repair +~~~~~~~~~~
+Repairs the GPT partition tables if it they become corrupted.
+gpt setenv +~~~~~~~~~~
+The 'gpt setenv' command will set a series of environment variables with +information about the partition named '<partition name>'. The variables are:
+gpt_partition_addr
- the starting offset of the partition in blocks as a hexadecimal number
+gpt_partition_size
- the size of the partition in blocks as a hexadecimal number
+gpt_partition_name
- the name of the partition
+gpt_partition_entry
- the partition number in the table, e.g. 1, 2, 3, etc.
Since eeef58401520 ("cmd: let gpt_partition_entry be hexadecimal") this is a hexadecimal number. As partitions are not required to be numbered start at 1:
%s/, e.g. 1, 2, 3, etc./as a hexadecimal number/
+gpt swap +~~~~~~~~
+Changes the names of all partitions that are named 'name1' to be 'name2', and +all partitions named 'name2' to be 'name1'. CONFIG_CMD_GPT_RENAME=y is +required.
+gpt verify +~~~~~~~~~~
+Sets return value $? to 0 (true) if the partition layout on the +specified disk matches the one in the provided partition string, and 1 (false) +if it does not match. If no partition string is specified, the command will +check if the disk is partitioned or not.
+gpt write +~~~~~~~~~
+(Re)writes the partition table on the disk to match the provided +partition string. It returns 0 on success or 1 on failure.
+Configuration +-------------
All other man-pages have Configuration after Examples.
+To use the 'gpt' command you must specify CONFIG_CMD_GPT=y. To enable 'gpt +read', 'gpt swap' and 'gpt rename', you must specify CONFIG_CMD_GPT_RENAME=y.
+Examples +~~~~~~~~
An example for gpt read would be nice.
+Create 6 partitions on a disk:: > +
- => setenv gpt_parts 'uuid_disk=bec9fc2a-86c1-483d-8a0e-0109732277d7;
name=boot,start=4M,size=128M,bootable,type=ebd0a0a2-b9e5-4433-87c0-68b6b72699c7,name=rootfs,size=3072M,type=0fc63daf-8483-4772-8e79-3d69d8477de4;name=system-data,size=512M,type=0fc63daf-8483-4772-8e79-3d69d8477de4;name=[ext],size=-,type=0fc63daf-8483-4772-8e79-3d69d8477de4;name=user,size=-,type=0fc63daf-8483-4772-8e79-3d69d8477de4;name=modules,size=100M,type=0fc63daf-8483-4772-8e79-3d69d8477de4;name=ramdisk,size=8M,type=0fc63daf-8483-4772-8e79-3d69d8477de4- => gpt write mmc 0 $gpt_parts
There is a starting single quotation mark, but I don't see an ending single quotation mark.
White-space is not allowed before 'name='. As ugly as it is, please, put the whole setenv command into a single line.
You cannot use a comma before name=. It must be a semicolon.
Looking at the code the sequence in the partition descriptors seems to be wrong. It should be
uuid (optional if CONFIG_RANDOM_UUID=y), type (optional, only usable for CONFIG_PARTITION_TYPE_GUID=y), name (mandatory), size (mandatory), start (optional), bootable (optional). . Please, use a command that you have actually tested and copy it verbatim. sandbox_defconfig has a host bind command to attach a file as drive. That makes testing easy.
+Verify that the device matches the partition layout described in the variable +$gpt_parts::
- => gpt verify mmc 0 $gpt_parts
How about adding output here:
=> gpt verify mmc 0 $gpt_parts; echo $? 0
Best regards
Heinrich
+Get the information about the partition named 'rootfs'::
- => gpt setenv mmc 0 rootfs
- => echo ${gpt_partition_addr}
- 2000
- => echo ${gpt_partition_size}
- 14a000
- => echo ${gpt_partition_name}
- rootfs
- => echo ${gpt_partition_entry}
- 2
+Get the list of partition names on the disk::
- => gpt enumerate
- => echo gpt_partition_list
- boot rootfs system-data [ext] user modules ramdisk
+Get the GUID for a disk::
- => gpt guid mmc 0
- bec9fc2a-86c1-483d-8a0e-0109732277d7
- => gpt guid mmc gpt_disk_uuid
- => echo ${gpt_disk_uuid}
- bec9fc2a-86c1-483d-8a0e-0109732277d7
diff --git a/doc/usage/index.rst b/doc/usage/index.rst index f45a7f5502..fa702920fa 100644 --- a/doc/usage/index.rst +++ b/doc/usage/index.rst @@ -66,6 +66,7 @@ Shell commands cmd/for cmd/fwu_mdata cmd/gpio
- cmd/gpt cmd/host cmd/imxtract cmd/load