Hi,
On 2/27/19 11:12 PM, liaoweixiong wrote:
> diff --git a/fs/pstore/Kconfig b/fs/pstore/Kconfig
> index defcb75..7dfe00b 100644
> --- a/fs/pstore/Kconfig
> +++ b/fs/pstore/Kconfig
> @@ -160,3 +160,117 @@ config PSTORE_BLK
> help
> This enables panic and oops message to be logged to a block dev
> where it can be read back at some later point.
> +
> +config PSTORE_BLKOOPS
> + tristate "pstore block with oops logger"
> + depends on PSTORE_BLK
> + help
> + This is a sample for pstore block with oops logger.
> +
> + It CANNOT record panic log as no read/write apis for panic registered.
APIs
> +
> + It CAN record oops log even power failure if
> + "PSTORE_BLKOOPS_BLKDEV" on Kconfig or "block-device" on dts or
> + "blkdev" on module parameter is valid.
> +
> + Otherwise, it can only record data to ram buffer, which will be
> + dropped when reboot.
dropped on reboot.
or
dropped when rebooting.
> +
> + NOTE that, there are three ways to set parameters of blkoops and
> + prioritize according to configuration flexibility. That is
> + Kconfig < device tree < module parameters. It means that the value can
> + be overwritten by higher priority settings.
> + 1. Kconfig
> + It just sets a default value.
> + 2. device tree
> + It is set on device tree, which will overwrites value from Kconfig,
overwrite the value from
Kconfig,
> + but can also be overwritten by module parameters.
> + 3. module parameters
> + It is the first priority. Take care of that blkoops will take lower
> + priority settings if higher priority one do not set.
> +
> +config PSTORE_BLKOOPS_DMESG_SIZE
> + int "dmesg size in kbytes for blkoops"
> + depends on PSTORE_BLKOOPS
> + default 64
> + help
> + This just sets size of dmesg (dmesg_size) for pstore/blk. The value
> + must be a multiple of 4096.
> +
> + NOTE that, there are three ways to set parameters of blkoops and
> + prioritize according to configuration flexibility. That is
> + Kconfig < device tree < module parameters. It means that the value can
> + be overwritten by higher priority settings.
> + 1. Kconfig
> + It just sets a default value.
> + 2. device tree
> + It is set on device tree, which will overwrites value from Kconfig,
overwrite the value from
Kconfig,
> + but can also be overwritten by module parameters.
> + 3. module parameters
> + It is the first priority. Take care of that blkoops will take lower
> + priority settings if higher priority one do not set.
> +
> +config PSTORE_BLKOOPS_TOTAL_SIZE
> + int "total size in kbytes for blkoops"
> + depends on PSTORE_BLKOOPS
> + default 0
> + help
> + The total size in kbytes pstore/blk can use. It must be less than or
> + equal to size of block device if @blkdev valid. If @total_size is zero
> + with @blkdev, @total_size will be set to equal to size of @blkdev.
set equal to size of @blkdev.
> + The value must be a multiple of 4096.
> +
> + NOTE that, there are three ways to set parameters of blkoops and
> + prioritize according to configuration flexibility. That is
> + Kconfig < device tree < module parameters. It means that the value can
> + be overwritten by higher priority settings.
> + 1. Kconfig
> + It just sets a default value.
> + 2. device tree
> + It is set on device tree, which will overwrites value from Kconfig,
overwrite the value from
Kconfig,
> + but can also be overwritten by module parameters.
> + 3. module parameters
> + It is the first priority. Take care of that blkoops will take lower
> + priority settings if higher priority one do not set.
> +
> +config PSTORE_BLKOOPS_BLKDEV
> + string "block device for blkoops"
> + depends on PSTORE_BLKOOPS
> + default ""
> + help
> + This just sets block device (blkdev) for pstore/blk. Pstore/blk
> + will record data to this block device to avoid losing data due to
> + power failure. So, If it is not set, pstore/blk will drop all data
if
> + when reboot.
on reboot.
> +
> + It accpet the following variants:
accepts
> + 1) <hex_major><hex_minor> device number in hexadecimal represents
> + itself no leading 0x, for example b302.
> + 2) /dev/<disk_name> represents the device number of disk
> + 3) /dev/<disk_name><decimal> represents the device number
> + of partition - device number of disk plus the partition number
> + 4) /dev/<disk_name>p<decimal> - same as the above, that form is
above; this form is
> + used when disk name of partitioned disk ends on a digit.
ends with a digit.
> + 5) PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF representing the
> + unique id of a partition if the partition table provides it.
> + The UUID may be either an EFI/GPT UUID, or refer to an MSDOS
> + partition using the format SSSSSSSS-PP, where SSSSSSSS is a zero-
> + filled hex representation of the 32-bit "NT disk signature", and PP
> + is a zero-filled hex representation of the 1-based partition
> number.
> + 6) PARTUUID=<UUID>/PARTNROFF=<int> to select a partition in relation
> + to a partition with a known unique id.
> + 7) <major>:<minor> major and minor number of the device separated by
> + a colon.
> +
> + NOTE that, there are three ways to set parameters of blkoops and
> + prioritize according to configuration flexibility. That is
> + Kconfig < device tree < module parameters. It means that the value can
> + be overwritten by higher priority settings.
> + 1. Kconfig
> + It just sets a default value.
> + 2. device tree
> + It is set on device tree, which will overwrites value from Kconfig,
overwrite the value from
Kconfig,
> + but can also be overwritten by module parameters.
> + 3. module parameters
> + It is the first priority. Take care of that blkoops will take lower
> + priority settings if higher priority one do not set.
--
~Randy
