/*
* Calculate the logical to physical mapping if not done already,
* then call the device strategy routine.
*
* In order to be able to swap to a file, the ext2_bmaparray() operation may not
* deadlock on memory. See ext2_bmap() for details.
*/
static int
ext2_strategy(struct vop_strategy_args *ap)
{
struct buf *bp = ap->a_bp;
struct vnode *vp = ap->a_vp;
struct inode *ip;
struct bufobj *bo;
int32_t blkno;
int error;
ip = VTOI(vp);
if (vp->v_type == VBLK || vp->v_type == VCHR)
panic("ext2_strategy: spec");
if (bp->b_blkno == bp->b_lblkno) {
error = ext2_bmaparray(vp, bp->b_lblkno, &blkno, NULL, NULL);
bp->b_blkno = blkno;
if (error) {
bp->b_error = error;
bp->b_ioflags |= BIO_ERROR;
bufdone(bp);
return (0);
}
if ((long)bp->b_blkno == -1)
vfs_bio_clrbuf(bp);
}
if ((long)bp->b_blkno == -1) {
bufdone(bp);
return (0);
}
bp->b_iooffset = dbtob(bp->b_blkno);
bo = VFSTOEXT2(vp->v_mount)->um_bo;
BO_STRATEGY(bo, bp);
return (0);
}
/*
* Bmap converts the logical block number of a file to its physical block
* number on the disk. The conversion is done by using the logical block
* number to index into the array of block pointers described by the dinode.
*
* BMAP must return the contiguous before and after run in bytes, inclusive
* of the returned block.
*
* ext2_bmap(struct vnode *a_vp, off_t a_loffset,
* off_t *a_doffsetp, int *a_runp, int *a_runb)
*/
int
ext2_bmap(struct vop_bmap_args *ap)
{
struct ext2_sb_info *fs;
ext2_daddr_t lbn;
ext2_daddr_t dbn;
int error;
/*
* Check for underlying vnode requests and ensure that logical
* to physical mapping is requested.
*/
if (ap->a_doffsetp == NULL)
return (0);
fs = VTOI(ap->a_vp)->i_e2fs;
KKASSERT(((int)ap->a_loffset & ((1 << fs->s_bshift) - 1)) == 0);
lbn = ap->a_loffset >> fs->s_bshift;
error = ext2_bmaparray(ap->a_vp, lbn, &dbn, NULL, NULL,
ap->a_runp, ap->a_runb);
if (error || dbn == (ext2_daddr_t)-1) {
*ap->a_doffsetp = NOOFFSET;
} else {
*ap->a_doffsetp = dbtodoff(fs, dbn);
if (ap->a_runp)
*ap->a_runp = (*ap->a_runp + 1) << fs->s_bshift;
if (ap->a_runb)
*ap->a_runb = *ap->a_runb << fs->s_bshift;
}
return (error);
}
/*
* Bmap converts the logical block number of a file to its physical block
* number on the disk. The conversion is done by using the logical block
* number to index into the array of block pointers described by the dinode.
*/
int
ext2_bmap(struct vop_bmap_args *ap)
{
daddr_t blkno;
int error;
/*
* Check for underlying vnode requests and ensure that logical
* to physical mapping is requested.
*/
if (ap->a_bop != NULL)
*ap->a_bop = &VTOI(ap->a_vp)->i_devvp->v_bufobj;
if (ap->a_bnp == NULL)
return (0);
if (VTOI(ap->a_vp)->i_flag & IN_E4EXTENTS)
error = ext4_bmapext(ap->a_vp, ap->a_bn, &blkno,
ap->a_runp, ap->a_runb);
else
error = ext2_bmaparray(ap->a_vp, ap->a_bn, &blkno,
ap->a_runp, ap->a_runb);
*ap->a_bnp = blkno;
return (error);
}
