diff options
| author | Randy Dunlap <rdunlap@infradead.org> | 2018-05-06 11:50:29 -0700 |
|---|---|---|
| committer | Jonathan Corbet <corbet@lwn.net> | 2018-05-08 09:18:53 -0600 |
| commit | f6dbf65b6558e9587570cb5b8345b967175285b5 (patch) | |
| tree | 2a50d3b207b6aa8626715b36add5e8bb22f311df /Documentation/block/cmdline-partition.txt | |
| parent | f318a44e15c16307b3f95751b674cb5d63789eb6 (diff) | |
Documentation: block: cmdline-partition.txt fixes and additions
Make the description of the kernel command line option "blkdevparts"
a bit more flowing and readable.
Fix a few typos.
Add the optional <size> and <offset> suffixes.
Note that size can be "-" to indicate all of the remaining space.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Cai Zhiyong <caizhiyong@huawei.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Diffstat (limited to 'Documentation/block/cmdline-partition.txt')
| -rw-r--r-- | Documentation/block/cmdline-partition.txt | 21 |
1 files changed, 14 insertions, 7 deletions
diff --git a/Documentation/block/cmdline-partition.txt b/Documentation/block/cmdline-partition.txt index 525b9f6d7fb4..760a3f7c3ed4 100644 --- a/Documentation/block/cmdline-partition.txt +++ b/Documentation/block/cmdline-partition.txt @@ -1,7 +1,9 @@ Embedded device command line partition parsing ===================================================================== -Support for reading the block device partition table from the command line. +The "blkdevparts" command line option adds support for reading the +block device partition table from the kernel command line. + It is typically used for fixed block (eMMC) embedded devices. It has no MBR, so saves storage space. Bootloader can be easily accessed by absolute address of data on the block device. @@ -14,22 +16,27 @@ blkdevparts=<blkdev-def>[;<blkdev-def>] <partdef> := <size>[@<offset>](part-name) <blkdev-id> - block device disk name, embedded device used fixed block device, - it's disk name also fixed. such as: mmcblk0, mmcblk1, mmcblk0boot0. + block device disk name. Embedded device uses fixed block device. + Its disk name is also fixed, such as: mmcblk0, mmcblk1, mmcblk0boot0. <size> partition size, in bytes, such as: 512, 1m, 1G. + size may contain an optional suffix of (upper or lower case): + K, M, G, T, P, E. + "-" is used to denote all remaining space. <offset> partition start address, in bytes. + offset may contain an optional suffix of (upper or lower case): + K, M, G, T, P, E. (part-name) - partition name, kernel send uevent with "PARTNAME". application can create - a link to block device partition with the name "PARTNAME". - user space application can access partition by partition name. + partition name. Kernel sends uevent with "PARTNAME". Application can + create a link to block device partition with the name "PARTNAME". + User space application can access partition by partition name. Example: - eMMC disk name is "mmcblk0" and "mmcblk0boot0" + eMMC disk names are "mmcblk0" and "mmcblk0boot0". bootargs: 'blkdevparts=mmcblk0:1G(data0),1G(data1),-;mmcblk0boot0:1m(boot),-(kernel)' |