STATIC int
xfs_qm_dqattach_one(
xfs_inode_t *ip,
xfs_dqid_t id,
uint type,
uint doalloc,
xfs_dquot_t **IO_idqpp)
{
xfs_dquot_t *dqp;
int error;
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
error = 0;
/*
* See if we already have it in the inode itself. IO_idqpp is &i_udquot
* or &i_gdquot. This made the code look weird, but made the logic a lot
* simpler.
*/
dqp = *IO_idqpp;
if (dqp) {
trace_xfs_dqattach_found(dqp);
return 0;
}
/*
* Find the dquot from somewhere. This bumps the reference count of
* dquot and returns it locked. This can return ENOENT if dquot didn't
* exist on disk and we didn't ask it to allocate; ESRCH if quotas got
* turned off suddenly.
*/
error = xfs_qm_dqget(ip->i_mount, ip, id, type,
doalloc | XFS_QMOPT_DOWARN, &dqp);
if (error)
return error;
trace_xfs_dqattach_get(dqp);
/*
* dqget may have dropped and re-acquired the ilock, but it guarantees
* that the dquot returned is the one that should go in the inode.
*/
*IO_idqpp = dqp;
xfs_dqunlock(dqp);
return 0;
}
STATIC int
xfs_qm_dqattach_one(
xfs_inode_t *ip,
xfs_dqid_t id,
uint type,
uint doalloc,
xfs_dquot_t *udqhint, /* hint */
xfs_dquot_t **IO_idqpp)
{
xfs_dquot_t *dqp;
int error;
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
error = 0;
/*
* See if we already have it in the inode itself. IO_idqpp is
* &i_udquot or &i_gdquot. This made the code look weird, but
* made the logic a lot simpler.
*/
dqp = *IO_idqpp;
if (dqp) {
trace_xfs_dqattach_found(dqp);
return 0;
}
/*
* udqhint is the i_udquot field in inode, and is non-NULL only
* when the type arg is group/project. Its purpose is to save a
* lookup by dqid (xfs_qm_dqget) by caching a group dquot inside
* the user dquot.
*/
if (udqhint) {
ASSERT(type == XFS_DQ_GROUP || type == XFS_DQ_PROJ);
xfs_dqlock(udqhint);
/*
* No need to take dqlock to look at the id.
*
* The ID can't change until it gets reclaimed, and it won't
* be reclaimed as long as we have a ref from inode and we
* hold the ilock.
*/
dqp = udqhint->q_gdquot;
if (dqp && be32_to_cpu(dqp->q_core.d_id) == id) {
ASSERT(*IO_idqpp == NULL);
*IO_idqpp = xfs_qm_dqhold(dqp);
xfs_dqunlock(udqhint);
return 0;
}
/*
* We can't hold a dquot lock when we call the dqget code.
* We'll deadlock in no time, because of (not conforming to)
* lock ordering - the inodelock comes before any dquot lock,
* and we may drop and reacquire the ilock in xfs_qm_dqget().
*/
xfs_dqunlock(udqhint);
}
/*
* Find the dquot from somewhere. This bumps the
* reference count of dquot and returns it locked.
* This can return ENOENT if dquot didn't exist on
* disk and we didn't ask it to allocate;
* ESRCH if quotas got turned off suddenly.
*/
error = xfs_qm_dqget(ip->i_mount, ip, id, type,
doalloc | XFS_QMOPT_DOWARN, &dqp);
if (error)
return error;
trace_xfs_dqattach_get(dqp);
/*
* dqget may have dropped and re-acquired the ilock, but it guarantees
* that the dquot returned is the one that should go in the inode.
*/
*IO_idqpp = dqp;
xfs_dqunlock(dqp);
return 0;
}
