/*
* Look up an EXT2FS dinode number to find its incore vnode, otherwise read it
* in from disk. If it is in core, wait for the lock bit to clear, then
* return the inode locked. Detection and handling of mount points must be
* done by the calling routine.
*/
static int
ext2_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp)
{
struct m_ext2fs *fs;
struct inode *ip;
struct ext2mount *ump;
struct buf *bp;
struct vnode *vp;
struct cdev *dev;
struct thread *td;
int i, error;
int used_blocks;
td = curthread;
error = vfs_hash_get(mp, ino, flags, td, vpp, NULL, NULL);
if (error || *vpp != NULL)
return (error);
ump = VFSTOEXT2(mp);
dev = ump->um_dev;
/*
* If this malloc() is performed after the getnewvnode()
* it might block, leaving a vnode with a NULL v_data to be
* found by ext2_sync() if a sync happens to fire right then,
* which will cause a panic because ext2_sync() blindly
* dereferences vp->v_data (as well it should).
*/
ip = malloc(sizeof(struct inode), M_EXT2NODE, M_WAITOK | M_ZERO);
/* Allocate a new vnode/inode. */
if ((error = getnewvnode("ext2fs", mp, &ext2_vnodeops, &vp)) != 0) {
*vpp = NULL;
free(ip, M_EXT2NODE);
return (error);
}
vp->v_data = ip;
ip->i_vnode = vp;
ip->i_e2fs = fs = ump->um_e2fs;
ip->i_ump = ump;
ip->i_number = ino;
lockmgr(vp->v_vnlock, LK_EXCLUSIVE, NULL);
error = insmntque(vp, mp);
if (error != 0) {
free(ip, M_EXT2NODE);
*vpp = NULL;
return (error);
}
error = vfs_hash_insert(vp, ino, flags, td, vpp, NULL, NULL);
if (error || *vpp != NULL)
return (error);
/* Read in the disk contents for the inode, copy into the inode. */
if ((error = bread(ump->um_devvp, fsbtodb(fs, ino_to_fsba(fs, ino)),
(int)fs->e2fs_bsize, NOCRED, &bp)) != 0) {
/*
* The inode does not contain anything useful, so it would
* be misleading to leave it on its hash chain. With mode
* still zero, it will be unlinked and returned to the free
* list by vput().
*/
brelse(bp);
vput(vp);
*vpp = NULL;
return (error);
}
/* convert ext2 inode to dinode */
ext2_ei2i((struct ext2fs_dinode *) ((char *)bp->b_data + EXT2_INODE_SIZE(fs) *
ino_to_fsbo(fs, ino)), ip);
ip->i_block_group = ino_to_cg(fs, ino);
ip->i_next_alloc_block = 0;
ip->i_next_alloc_goal = 0;
/*
* Now we want to make sure that block pointers for unused
* blocks are zeroed out - ext2_balloc depends on this
* although for regular files and directories only
*/
if(S_ISDIR(ip->i_mode) || S_ISREG(ip->i_mode)) {
used_blocks = (ip->i_size+fs->e2fs_bsize-1) / fs->e2fs_bsize;
for (i = used_blocks; i < EXT2_NDIR_BLOCKS; i++)
ip->i_db[i] = 0;
}
/*
ext2_print_inode(ip);
*/
bqrelse(bp);
/*
* Initialize the vnode from the inode, check for aliases.
* Note that the underlying vnode may have changed.
*/
if ((error = ext2_vinit(mp, &ext2_fifoops, &vp)) != 0) {
vput(vp);
*vpp = NULL;
return (error);
}
/*
* Finish inode initialization.
*/
/*
* Set up a generation number for this inode if it does not
* already have one. This should only happen on old filesystems.
*/
if (ip->i_gen == 0) {
ip->i_gen = random() / 2 + 1;
if ((vp->v_mount->mnt_flag & MNT_RDONLY) == 0)
ip->i_flag |= IN_MODIFIED;
}
*vpp = vp;
return (0);
}
/*
* Look up an EXT2FS dinode number to find its incore vnode, otherwise read it
* in from disk. If it is in core, wait for the lock bit to clear, then
* return the inode locked. Detection and handling of mount points must be
* done by the calling routine.
*/
static int
ext2_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp)
{
struct m_ext2fs *fs;
struct inode *ip;
struct ext2mount *ump;
struct buf *bp;
struct vnode *vp;
struct thread *td;
int i, error;
int used_blocks;
td = curthread;
error = vfs_hash_get(mp, ino, flags, td, vpp, NULL, NULL);
if (error || *vpp != NULL)
return (error);
ump = VFSTOEXT2(mp);
ip = malloc(sizeof(struct inode), M_EXT2NODE, M_WAITOK | M_ZERO);
/* Allocate a new vnode/inode. */
if ((error = getnewvnode("ext2fs", mp, &ext2_vnodeops, &vp)) != 0) {
*vpp = NULL;
free(ip, M_EXT2NODE);
return (error);
}
vp->v_data = ip;
ip->i_vnode = vp;
ip->i_e2fs = fs = ump->um_e2fs;
ip->i_ump = ump;
ip->i_number = ino;
lockmgr(vp->v_vnlock, LK_EXCLUSIVE, NULL);
error = insmntque(vp, mp);
if (error != 0) {
free(ip, M_EXT2NODE);
*vpp = NULL;
return (error);
}
error = vfs_hash_insert(vp, ino, flags, td, vpp, NULL, NULL);
if (error || *vpp != NULL)
return (error);
/* Read in the disk contents for the inode, copy into the inode. */
if ((error = bread(ump->um_devvp, fsbtodb(fs, ino_to_fsba(fs, ino)),
(int)fs->e2fs_bsize, NOCRED, &bp)) != 0) {
/*
* The inode does not contain anything useful, so it would
* be misleading to leave it on its hash chain. With mode
* still zero, it will be unlinked and returned to the free
* list by vput().
*/
brelse(bp);
vput(vp);
*vpp = NULL;
return (error);
}
/* convert ext2 inode to dinode */
ext2_ei2i((struct ext2fs_dinode *)((char *)bp->b_data + EXT2_INODE_SIZE(fs) *
ino_to_fsbo(fs, ino)), ip);
ip->i_block_group = ino_to_cg(fs, ino);
ip->i_next_alloc_block = 0;
ip->i_next_alloc_goal = 0;
/*
* Now we want to make sure that block pointers for unused
* blocks are zeroed out - ext2_balloc depends on this
* although for regular files and directories only
*
* If IN_E4EXTENTS is enabled, unused blocks are not zeroed
* out because we could corrupt the extent tree.
*/
if (!(ip->i_flag & IN_E4EXTENTS) &&
(S_ISDIR(ip->i_mode) || S_ISREG(ip->i_mode))) {
used_blocks = howmany(ip->i_size, fs->e2fs_bsize);
for (i = used_blocks; i < EXT2_NDIR_BLOCKS; i++)
ip->i_db[i] = 0;
}
#ifdef EXT2FS_DEBUG
ext2_print_inode(ip);
#endif
bqrelse(bp);
/*
* Initialize the vnode from the inode, check for aliases.
* Note that the underlying vnode may have changed.
*/
if ((error = ext2_vinit(mp, &ext2_fifoops, &vp)) != 0) {
vput(vp);
*vpp = NULL;
return (error);
}
/*
* Finish inode initialization.
*/
*vpp = vp;
return (0);
}
