Messages in this thread | | | Date | Fri, 18 Sep 2015 09:41:43 -0700 | Subject | Re: [PATCH] pramdisk: new block disk driver to perform persistent storage | From | Dan Williams <> |
| |
On Fri, Sep 18, 2015 at 9:18 AM, Ross Zwisler <ross.zwisler@linux.intel.com> wrote: > On Fri, Sep 18, 2015 at 03:46:30PM +0800, Lin Yongting wrote: >> In embed devices, user space applications will use reserved memory >> (i.e. persistent memory) to store business data, the data is kept >> in this memory region after system rebooting or panic. >> >> pramdisk is a block disk driver based on Persistent memory, it provide >> file system interface for application to read/write data in persistent >> memory. Application can use pramdisk to store log file or business data >> in persistent memory in the way of file system operation, avoid operating >> or managing memory directly. >> >> pramdisk support multiple Persistent menory regions and each one is a >> block device named as /dev/pram<N>. >> >> Usage: >> modprobe pramdisk.ko pmem=<size1>@<addr2> [ pmem=<size2>@<addr2> ... ] >> >> For example: >> modprobe pramdisk.ko pmem=20M@2050M pmem=20M@2150M >> mkfs.ext3 /dev/pram1 >> mkdir /tmp/test1 >> mount -t ext3 /dev/pram1 /tmp/test1 >> >> Signed-off-by: Lin Yongting <linyongting@huawei.com> >> Signed-off-by: Wang xiaozhe <wangxiaozhe@huawei.com> > > I think you already have this functionality with the PMEM driver and the > memmap=nn[KMG]!ss[KMG] command line parameter? What are you trying to > accomplish with this driver that you can't do with PMEM?
Moreover, if your embedded firmware publishes persistent memory ranges you can reuse the drivers/nvdimm/e820.c driver. As long as your platform code in the kernel names those iomem_resource(s) as ""Persistent Memory (legacy)" they will be auto discovered and surfaced by the libnvidmm sub-system.
| |