P2K(3) Library Functions Manual P2K(3)

p2k — puffs to kernel vfs translation library

p2k Library (libp2k, -lp2k)

#include <rump/p2k.h>

struct p2k_mount *
p2k_init(uint32_t puffs_flags);

void
p2k_cancel(struct p2k_mount *p2m, int error);

int
p2k_setup_fs(struct p2k_mount *p2m, const char *vfsname, const char *devpath, const char *mountpath, int mntflags, void *arg, size_t alen);

int
p2k_setup_diskfs(struct p2k_mount *p2m, const char *vfsname, const char *devpath, struct ukfs_part *part, const char *mountpath, int mntflags, void *arg, size_t alen);

int
p2k_mainloop(struct p2k_mount *p2m);

int
p2k_run_fs(const char *vfsname, const char *devpath, const char *mountpath, int mntflags, void *arg, size_t alen, uint32_t puffs_flags);

int
p2k_run_diskfs(const char *vfsname, const char *devpath, struct ukfs_part *part, const char *mountpath, int mntflags, void *arg, size_t alen, uint32_t puffs_flags);

The p2k library translates the puffs protocol to the kernel vfs(9) protocol and back again. It can therefore be used to mount and run kernel file system code as a userspace daemon.

Calling the library interface function mounts the file system and, if successful, starts handling requests. The parameters are handled by () (see ukfs(3)), with the exception that mountpath and puffs_flags are handled by puffs(3). The "run_fs" variants of the interfaces are provided as a convenience for the common case. They execute all of init, setup and mainloop in one call.

The following environment variables affect the behaviour of p2k. They are useful mostly for debugging purposes. The flags are environment variables because typically the command line arguments to p2k utilities are parsed using versions not aware of p2k options; for example, the rump_cd9660(8) arguments are really parsed by mount_cd9660(8).

Do not detach from tty and print information about each puffs operation. In case the daemon receives SIGINFO (typically from ctrl-T), it dumps out the status of the mount point. Sending SIGUSR1 causes a dump of all the vnodes (verbose).
Do not detach from tty.
Do not use the puffs page cache.
Do not use the puffs name cache.
Do not use the puffs page or name cache.
If set, use the value of the variable to determine the UID of the caller of each operation instead of the actual caller supplied by puffs(3). This can be used for example to simplify modifying an OS installation's root image as a non-root user.

puffs(3), rump(3), ukfs(3), rump_cd9660(8), rump_efs(8), rump_ext2fs(8), rump_ffs(8), rump_hfs(8), rump_lfs(8), rump_msdos(8), rump_nfs(8), rump_ntfs(8), rump_syspuffs(8), rump_sysvbfs(8), rump_tmpfs(8), rump_udf(8)

October 13, 2024 NetBSD 11.0