NAME
lfs_markv —
rewrite disk blocks to new
disk locations
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <sys/types.h>
#include <ufs/lfs/lfs.h>
int
lfs_markv(
fsid_t
*fsidp,
BLOCK_INFO
*blkiov,
int blkcnt);
DESCRIPTION
lfs_markv() rewrites the blocks specified in
blkiov to new disk locations, for the purposes of
grouping them next to one another, or to move them out of a segment to clean
it. All fields of the BLOCK_INFO structure must be filled in, except for
bi_segcreate. If
bi_daddr is not
the correct current address for logical block
bi_lbn of
the file with inode number
bi_inode, or if the file's
version number does not match
bi_version, the block will
not be written to disk, but no error will be returned.
The
fsidp argument contains the id of the file system to
which the inodes and blocks belong. The
bi_bp field
contains
bi_size bytes of data to be written into the
appropriate block. If
bi_lbn is specified as
LFS_UNUSED_LBN, the inode itself will be rewritten.
The
blkiov argument is an array of BLOCK_INFO structures
(see below). The
blkcnt argument determines the size of
the
blkiov array.
typedef struct block_info {
ino_t bi_inode; /* inode # */
ufs_daddr_t bi_lbn; /* logical block w/in file */
ufs_daddr_t bi_daddr; /* disk address of block */
time_t bi_segcreate; /* origin segment create time */
int bi_version; /* file version number */
void *bi_bp; /* data buffer */
int bi_size; /* size of the block (if fragment) */
} BLOCK_INFO;
RETURN VALUES
lfs_markv() returns 0 on success, or -1 on error.
ERRORS
An error return from
lfs_markv() indicates:
-
-
- [
EFAULT
]
- fsidp points outside the process's
allocated address space.
-
-
- [
EINVAL
]
- *fsidp does not specify a valid file
system.
-
-
- [
EBUSY
]
- One or more of the inodes whose blocks were to be written
was locked, and its blocks were not rewritten.
SEE ALSO
lfs_segclean(2),
lfs_segwait(2),
lfs_cleanerd(8)
HISTORY
The
lfs_markv() function call appeared in
4.4BSD.
BUGS
The functionality of
lfs_markv() does not really belong in
user space. Among other things it could be used to work around the
SF_IMMUTABLE and SF_APPEND file flags (see
chflags(2)).