RUMP_ETFS(3) BSD Library Functions Manual RUMP_ETFS(3)NAMErump_etfs — rump host file system interface
LIBRARY
rump kernel (librump, -lrump)
SYNOPSIS
#include <rump/rump.h>
int
rump_pub_etfs_register(const char *key, const char *hostpath,
enum rump_etfs_type ftype);
int
rump_pub_etfs_register_withsize(const char *key, const char *hostpath,
enum rump_etfs_type ftype, uint64_t begin, uint64_t size);
int
rump_pub_etfs_remove(const char *key);
DESCRIPTION
The rump ExtraTerrestrial File System (rump_etfs) is used to provide
access to the host file system namespace within a rump kernel.
The operation is based on registered key values which each map to a
hostpath. A key must be an absolute path (i.e. begin with “/”). Multi‐
ple leading slashes are collapsed to one (i.e. “/key” is the same as
“//key”). The rest of the path, including slashes, is compared verbatim
(i.e. “/key/path” does not match “/key//path”).
The hostpath is interpreted in host system context for the current work‐
ing directory and can be either absolute or relative.
The ftype parameter specifies how etfs file will be presented and does
not have to match the host type, although some limitations apply. Possi‐
ble values are:
RUMP_ETFS_REG regular file.
RUMP_ETFS_BLK block device. This is often used when mapping
file system images.
RUMP_ETFS_CHR character device.
RUMP_ETFS_DIR directory. This option is valid only when
hostpath is a directory. The immediate chil‐
dren of the host directory will be accessible
inside a rump kernel.
RUMP_ETFS_DIR_SUBDIRS directory. This option is valid only when
hostpath is a directory. This option recur‐
sively applies to all subdirectories, and
allows a rump kernel to access an entire direc‐
tory tree.
The interfaces are:
rump_pub_etfs_register(key, hostpath, ftype)
Map key to a file of type ftype with the contents of hostpath.
rump_pub_etfs_register_withsize(key, hostpath, ftype, begin, size)
Like the above, but map only [begin, begin+size] from hostpath.
This is useful when mapping disk images where only one partition is
relevant to the application. If size is given the special value
RUMP_ETFS_SIZE_ENDOFF, the underlying file is mapped from begin to
the end of the file.
rump_pub_etfs_remove(key)
Remove etfs mapping for key. This routine may be called only if
the file related to the mapping is not in use.
EXAMPLES
Map a host image file to a mountable /dev/harddisk path using window off‐
sets from the disklabel.
rump_pub_etfs_register_withsize("/dev/harddisk", "disk.img",
RUMP_ETFS_BLK,
pp->p_offset << DEV_BSHIFT, pp->p_size << DEV_BSHIFT);
Make the host kernel module directory hierarchy available within the rump
kernel.
rump_pub_etfs_register("/stand/i386/5.99.41",
"/stand/i386/5.99.41", RUMP_ETFS_DIR_SUBDIRS);
SEE ALSOrump(3)HISTORYrump_etfs first appeared in NetBSD 6.0.
BSD February 3, 2011 BSD
