P2K(3)

P2K(3) | Library Functions Manual | P2K(3)

# NAME

`p2k` —
puffs to kernel vfs translation library

# LIBRARY

p2k Library (libp2k, -lp2k)

# SYNOPSIS

`#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);

`p2k_setup_diskfs`(struct p2k_mount *p2m, const char *vfsname, const char *devpath, int partition, 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, int partition, const char *mountpath, int mntflags, void *arg, size_t alen, uint32_t puffs_flags);

# DESCRIPTION

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 `ukfs_mount`() (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.

# ENVIRONMENT

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).

`P2K_DEBUG`
  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).
`P2K_NODETACH`
  Do not detach from tty.
`P2K_NOCACHE_PAGE`
  Do not use the puffs page cache.
`P2K_NOCACHE_NAME`
  Do not use the puffs name cache.
`P2K_NOCACHE`
  Do not use the puffs page or name cache.
`P2K_WIZARDUID`
  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.

# SEE ALSO

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)

July 11, 2022 | NetBSD 10.1