linux - How to access tmpfs file under /dev/shm, created by user-space process, in a kernel module? -


i created file under /dev/shm (tmpfs) user-space, mmap'd file process address space , pushed contents. now, how map file again under kernel virtual address space access contents written user-space process. of course know how read using filp_open() , vfs_read(), want access contents using direct memory pointers similar mmap() user-space processes. want similar what's in mm/shmem.c, instead of doing mapping between user-space vma , /sysvxxx file, want kernel virtual address vma instead. can in that?

thanks..

only code implements tmpfs knows files' memory is.

you have implement own fs, or use 1 allows define own mmap implementation (like procfs or sysfs).


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