Aren/NetBSD
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

- Use an empty snap block list to set the initial file size. Snapshot is

Browse Source 
now valid from the beginning.  No need to copy the last fs block two times.
- No need to allocate the cylinder group blocks twice.
- cgbuf -> sbbuf
This commit is contained in:
hannken 2005-05-25 11:07:13 +00:00
parent bf77c4e4b3
commit a69fbd6a18
1 changed files with 16 additions and 33 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

49
sys/ufs/ffs/ffs_snapshot.c
View File

@ -36,7 +36,7 @@
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: ffs_snapshot.c,v 1.15 2005/05/22 08:35:28 hannken Exp $");
__KERNEL_RCSID(0, "$NetBSD: ffs_snapshot.c,v 1.16 2005/05/25 11:07:13 hannken Exp $");
#if defined(_KERNEL_OPT)
#include "opt_ffs.h"
@ -150,7 +150,7 @@ ffs_snapshot(mp, vp, ctime)
long redo = 0;
int32_t *lp;
void *space;
caddr_t cgbuf;
caddr_t sbbuf = NULL;
struct ufsmount *ump = VFSTOUFS(mp);
struct fs *copy_fs = NULL, *fs = ump->um_fs;
struct proc *p = curproc;
@ -200,15 +200,14 @@ ffs_snapshot(mp, vp, ctime)
ip = VTOI(vp);
devvp = ip->i_devvp;
/*
* Allocate and copy the last block contents so as to be able
* to set size to that of the filesystem.
* Write an empty list of preallocated blocks to the end of
* the snapshot to set size to at least that of the filesystem.
*/
numblks = howmany(fs->fs_size, fs->fs_frag);
cgbuf = malloc(fs->fs_bsize, M_UFSMNT, M_WAITOK);
if ((error = readfsblk(vp, cgbuf, numblks - 1)) != 0)
goto out;
blkno = 1;
blkno = ufs_rw64(blkno, ns);
error = vn_rdwr(UIO_WRITE, vp,
cgbuf, fs->fs_bsize, lblktosize(fs, (off_t)(numblks - 1)),
(caddr_t)&blkno, sizeof(blkno), lblktosize(fs, (off_t)numblks),
UIO_SYSSPACE, IO_NODELOCKED|IO_UNIT, p->p_ucred, NULL, NULL);
if (error)
goto out;
@ -247,16 +246,6 @@ ffs_snapshot(mp, vp, ctime)
goto out;
bawrite(nbp);
}
/*
* Allocate all cylinder group blocks.
*/
for (cg = 0; cg < fs->fs_ncg; cg++) {
error = VOP_BALLOC(vp, lfragtosize(fs, cgtod(fs, cg)),
fs->fs_bsize, KERNCRED, 0, &nbp);
if (error)
goto out;
bawrite(nbp);
}
/*
* Copy all the cylinder group maps. Although the
* filesystem is still active, we hope that only a few
@ -301,13 +290,6 @@ ffs_snapshot(mp, vp, ctime)
}
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
microtime(&starttime);
/*
* The last block saved before may have changed so update it now.
*/
if ((error = readfsblk(vp, cgbuf, numblks - 1)) != 0)
goto out1;
if ((error = writevnblk(vp, cgbuf, numblks - 1)) != 0)
goto out1;
/*
* First, copy all the cylinder group maps that have changed.
*/
@ -327,14 +309,15 @@ ffs_snapshot(mp, vp, ctime)
* Grab a copy of the superblock and its summary information.
* We delay writing it until the suspension is released below.
*/
sbbuf = malloc(fs->fs_bsize, M_UFSMNT, M_WAITOK);
loc = blkoff(fs, fs->fs_sblockloc);
if (loc > 0)
bzero(&cgbuf[0], loc);
copy_fs = (struct fs *)(cgbuf + loc);
bzero(&sbbuf[0], loc);
copy_fs = (struct fs *)(sbbuf + loc);
bcopy(fs, copy_fs, fs->fs_sbsize);
size = fs->fs_bsize < SBLOCKSIZE ? fs->fs_bsize : SBLOCKSIZE;
if (fs->fs_sbsize < size)
bzero(&cgbuf[loc + fs->fs_sbsize], size - fs->fs_sbsize);
bzero(&sbbuf[loc + fs->fs_sbsize], size - fs->fs_sbsize);
size = blkroundup(fs, fs->fs_cssize);
if (fs->fs_contigsumsize > 0)
size += fs->fs_ncg * sizeof(int32_t);
@ -593,8 +576,8 @@ out1:
*/
for (i = 0; i < snaplistsize; i++)
snapblklist[i] = ufs_rw64(snapblklist[i], ns);
error = vn_rdwr(UIO_WRITE, vp,
(caddr_t)snapblklist, snaplistsize*sizeof(ufs2_daddr_t), ip->i_size,
error = vn_rdwr(UIO_WRITE, vp, (caddr_t)snapblklist,
snaplistsize*sizeof(ufs2_daddr_t), lblktosize(fs, (off_t)numblks),
UIO_SYSSPACE, IO_NODELOCKED|IO_UNIT, p->p_ucred, NULL, NULL);
for (i = 0; i < snaplistsize; i++)
snapblklist[i] = ufs_rw64(snapblklist[i], ns);
@ -648,7 +631,7 @@ done:
brelse(nbp);
fs->fs_snapinum[snaploc] = 0;
}
bcopy(cgbuf, nbp->b_data, fs->fs_bsize);
bcopy(sbbuf, nbp->b_data, fs->fs_bsize);
bawrite(nbp);
}
out:
@ -687,8 +670,8 @@ out:
simple_unlock(&global_v_numoutput_slock);
splx(s);
}
if (cgbuf)
free(cgbuf, M_UFSMNT);
if (sbbuf)
free(sbbuf, M_UFSMNT);
if (fs->fs_active != 0) {
FREE(fs->fs_active, M_DEVBUF);
fs->fs_active = 0;