/*
* Read in the in-core dquot's on-disk metadata and return the buffer.
* Returns ENOENT to signal a hole.
*/
STATIC int
xfs_dquot_disk_read(
struct xfs_mount *mp,
struct xfs_dquot *dqp,
struct xfs_buf **bpp)
{
struct xfs_bmbt_irec map;
struct xfs_buf *bp;
struct xfs_inode *quotip = xfs_quota_inode(mp, dqp->dq_flags);
uint lock_mode;
int nmaps = 1;
int error;
lock_mode = xfs_ilock_data_map_shared(quotip);
if (!xfs_this_quota_on(mp, dqp->dq_flags)) {
/*
* Return if this type of quotas is turned off while we
* didn't have the quota inode lock.
*/
xfs_iunlock(quotip, lock_mode);
return -ESRCH;
}
/*
* Find the block map; no allocations yet
*/
error = xfs_bmapi_read(quotip, dqp->q_fileoffset,
XFS_DQUOT_CLUSTER_SIZE_FSB, &map, &nmaps, 0);
xfs_iunlock(quotip, lock_mode);
if (error)
return error;
ASSERT(nmaps == 1);
ASSERT(map.br_blockcount >= 1);
ASSERT(map.br_startblock != DELAYSTARTBLOCK);
if (map.br_startblock == HOLESTARTBLOCK)
return -ENOENT;
trace_xfs_dqtobp_read(dqp);
/*
* store the blkno etc so that we don't have to do the
* mapping all the time
*/
dqp->q_blkno = XFS_FSB_TO_DADDR(mp, map.br_startblock);
error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp, dqp->q_blkno,
mp->m_quotainfo->qi_dqchunklen, 0, &bp,
&xfs_dquot_buf_ops);
if (error) {
ASSERT(bp == NULL);
return error;
}
ASSERT(xfs_buf_islocked(bp));
xfs_buf_set_ref(bp, XFS_DQUOT_REF);
*bpp = bp;
return 0;
}
/*
* Given the file system, inode OR id, and type (UDQUOT/GDQUOT), return a
* a locked dquot, doing an allocation (if requested) as needed.
* When both an inode and an id are given, the inode's id takes precedence.
* That is, if the id changes while we don't hold the ilock inside this
* function, the new dquot is returned, not necessarily the one requested
* in the id argument.
*/
int
xfs_qm_dqget(
xfs_mount_t *mp,
xfs_inode_t *ip, /* locked inode (optional) */
xfs_dqid_t id, /* uid/projid/gid depending on type */
uint type, /* XFS_DQ_USER/XFS_DQ_PROJ/XFS_DQ_GROUP */
uint flags, /* DQALLOC, DQSUSER, DQREPAIR, DOWARN */
xfs_dquot_t **O_dqpp) /* OUT : locked incore dquot */
{
struct xfs_quotainfo *qi = mp->m_quotainfo;
struct radix_tree_root *tree = xfs_dquot_tree(qi, type);
struct xfs_dquot *dqp;
int error;
ASSERT(XFS_IS_QUOTA_RUNNING(mp));
if ((! XFS_IS_UQUOTA_ON(mp) && type == XFS_DQ_USER) ||
(! XFS_IS_PQUOTA_ON(mp) && type == XFS_DQ_PROJ) ||
(! XFS_IS_GQUOTA_ON(mp) && type == XFS_DQ_GROUP)) {
return (ESRCH);
}
#ifdef DEBUG
if (xfs_do_dqerror) {
if ((xfs_dqerror_target == mp->m_ddev_targp) &&
(xfs_dqreq_num++ % xfs_dqerror_mod) == 0) {
xfs_debug(mp, "Returning error in dqget");
return (EIO);
}
}
ASSERT(type == XFS_DQ_USER ||
type == XFS_DQ_PROJ ||
type == XFS_DQ_GROUP);
if (ip) {
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
ASSERT(xfs_inode_dquot(ip, type) == NULL);
}
#endif
restart:
mutex_lock(&qi->qi_tree_lock);
dqp = radix_tree_lookup(tree, id);
if (dqp) {
xfs_dqlock(dqp);
if (dqp->dq_flags & XFS_DQ_FREEING) {
xfs_dqunlock(dqp);
mutex_unlock(&qi->qi_tree_lock);
trace_xfs_dqget_freeing(dqp);
delay(1);
goto restart;
}
dqp->q_nrefs++;
mutex_unlock(&qi->qi_tree_lock);
trace_xfs_dqget_hit(dqp);
XFS_STATS_INC(xs_qm_dqcachehits);
*O_dqpp = dqp;
return 0;
}
mutex_unlock(&qi->qi_tree_lock);
XFS_STATS_INC(xs_qm_dqcachemisses);
/*
* Dquot cache miss. We don't want to keep the inode lock across
* a (potential) disk read. Also we don't want to deal with the lock
* ordering between quotainode and this inode. OTOH, dropping the inode
* lock here means dealing with a chown that can happen before
* we re-acquire the lock.
*/
if (ip)
xfs_iunlock(ip, XFS_ILOCK_EXCL);
error = xfs_qm_dqread(mp, id, type, flags, &dqp);
if (ip)
xfs_ilock(ip, XFS_ILOCK_EXCL);
if (error)
return error;
if (ip) {
/*
* A dquot could be attached to this inode by now, since
* we had dropped the ilock.
*/
if (xfs_this_quota_on(mp, type)) {
struct xfs_dquot *dqp1;
dqp1 = xfs_inode_dquot(ip, type);
if (dqp1) {
xfs_qm_dqdestroy(dqp);
dqp = dqp1;
xfs_dqlock(dqp);
goto dqret;
}
} else {
/* inode stays locked on return */
xfs_qm_dqdestroy(dqp);
return XFS_ERROR(ESRCH);
}
}
mutex_lock(&qi->qi_tree_lock);
error = -radix_tree_insert(tree, id, dqp);
if (unlikely(error)) {
WARN_ON(error != EEXIST);
/*
* Duplicate found. Just throw away the new dquot and start
* over.
*/
mutex_unlock(&qi->qi_tree_lock);
trace_xfs_dqget_dup(dqp);
xfs_qm_dqdestroy(dqp);
XFS_STATS_INC(xs_qm_dquot_dups);
goto restart;
}
/*
* We return a locked dquot to the caller, with a reference taken
*/
xfs_dqlock(dqp);
dqp->q_nrefs = 1;
qi->qi_dquots++;
mutex_unlock(&qi->qi_tree_lock);
dqret:
ASSERT((ip == NULL) || xfs_isilocked(ip, XFS_ILOCK_EXCL));
trace_xfs_dqget_miss(dqp);
*O_dqpp = dqp;
return (0);
}
/*
* Maps a dquot to the buffer containing its on-disk version.
* This returns a ptr to the buffer containing the on-disk dquot
* in the bpp param, and a ptr to the on-disk dquot within that buffer
*/
STATIC int
xfs_qm_dqtobp(
xfs_trans_t **tpp,
xfs_dquot_t *dqp,
xfs_disk_dquot_t **O_ddpp,
xfs_buf_t **O_bpp,
uint flags)
{
struct xfs_bmbt_irec map;
int nmaps = 1, error;
struct xfs_buf *bp;
struct xfs_inode *quotip = xfs_dq_to_quota_inode(dqp);
struct xfs_mount *mp = dqp->q_mount;
xfs_dqid_t id = be32_to_cpu(dqp->q_core.d_id);
struct xfs_trans *tp = (tpp ? *tpp : NULL);
uint lock_mode;
dqp->q_fileoffset = (xfs_fileoff_t)id / mp->m_quotainfo->qi_dqperchunk;
lock_mode = xfs_ilock_data_map_shared(quotip);
if (!xfs_this_quota_on(dqp->q_mount, dqp->dq_flags)) {
/*
* Return if this type of quotas is turned off while we
* didn't have the quota inode lock.
*/
xfs_iunlock(quotip, lock_mode);
return ESRCH;
}
/*
* Find the block map; no allocations yet
*/
error = xfs_bmapi_read(quotip, dqp->q_fileoffset,
XFS_DQUOT_CLUSTER_SIZE_FSB, &map, &nmaps, 0);
xfs_iunlock(quotip, lock_mode);
if (error)
return error;
ASSERT(nmaps == 1);
ASSERT(map.br_blockcount == 1);
/*
* Offset of dquot in the (fixed sized) dquot chunk.
*/
dqp->q_bufoffset = (id % mp->m_quotainfo->qi_dqperchunk) *
sizeof(xfs_dqblk_t);
ASSERT(map.br_startblock != DELAYSTARTBLOCK);
if (map.br_startblock == HOLESTARTBLOCK) {
/*
* We don't allocate unless we're asked to
*/
if (!(flags & XFS_QMOPT_DQALLOC))
return ENOENT;
ASSERT(tp);
error = xfs_qm_dqalloc(tpp, mp, dqp, quotip,
dqp->q_fileoffset, &bp);
if (error)
return error;
tp = *tpp;
} else {
trace_xfs_dqtobp_read(dqp);
/*
* store the blkno etc so that we don't have to do the
* mapping all the time
*/
dqp->q_blkno = XFS_FSB_TO_DADDR(mp, map.br_startblock);
error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
dqp->q_blkno,
mp->m_quotainfo->qi_dqchunklen,
0, &bp, &xfs_dquot_buf_ops);
if (error == EFSCORRUPTED && (flags & XFS_QMOPT_DQREPAIR)) {
xfs_dqid_t firstid = (xfs_dqid_t)map.br_startoff *
mp->m_quotainfo->qi_dqperchunk;
ASSERT(bp == NULL);
error = xfs_qm_dqrepair(mp, tp, dqp, firstid, &bp);
}
if (error) {
ASSERT(bp == NULL);
return XFS_ERROR(error);
}
}
ASSERT(xfs_buf_islocked(bp));
*O_bpp = bp;
*O_ddpp = bp->b_addr + dqp->q_bufoffset;
return (0);
}
/*
* Allocate a block and fill it with dquots.
* This is called when the bmapi finds a hole.
*/
STATIC int
xfs_qm_dqalloc(
xfs_trans_t **tpp,
xfs_mount_t *mp,
xfs_dquot_t *dqp,
xfs_inode_t *quotip,
xfs_fileoff_t offset_fsb,
xfs_buf_t **O_bpp)
{
xfs_fsblock_t firstblock;
xfs_bmap_free_t flist;
xfs_bmbt_irec_t map;
int nmaps, error, committed;
xfs_buf_t *bp;
xfs_trans_t *tp = *tpp;
ASSERT(tp != NULL);
trace_xfs_dqalloc(dqp);
/*
* Initialize the bmap freelist prior to calling bmapi code.
*/
xfs_bmap_init(&flist, &firstblock);
xfs_ilock(quotip, XFS_ILOCK_EXCL);
/*
* Return if this type of quotas is turned off while we didn't
* have an inode lock
*/
if (!xfs_this_quota_on(dqp->q_mount, dqp->dq_flags)) {
xfs_iunlock(quotip, XFS_ILOCK_EXCL);
return (ESRCH);
}
xfs_trans_ijoin(tp, quotip, XFS_ILOCK_EXCL);
nmaps = 1;
error = xfs_bmapi_write(tp, quotip, offset_fsb,
XFS_DQUOT_CLUSTER_SIZE_FSB, XFS_BMAPI_METADATA,
&firstblock, XFS_QM_DQALLOC_SPACE_RES(mp),
&map, &nmaps, &flist);
if (error)
goto error0;
ASSERT(map.br_blockcount == XFS_DQUOT_CLUSTER_SIZE_FSB);
ASSERT(nmaps == 1);
ASSERT((map.br_startblock != DELAYSTARTBLOCK) &&
(map.br_startblock != HOLESTARTBLOCK));
/*
* Keep track of the blkno to save a lookup later
*/
dqp->q_blkno = XFS_FSB_TO_DADDR(mp, map.br_startblock);
/* now we can just get the buffer (there's nothing to read yet) */
bp = xfs_trans_get_buf(tp, mp->m_ddev_targp,
dqp->q_blkno,
mp->m_quotainfo->qi_dqchunklen,
0);
if (!bp) {
error = ENOMEM;
goto error1;
}
bp->b_ops = &xfs_dquot_buf_ops;
/*
* Make a chunk of dquots out of this buffer and log
* the entire thing.
*/
xfs_qm_init_dquot_blk(tp, mp, be32_to_cpu(dqp->q_core.d_id),
dqp->dq_flags & XFS_DQ_ALLTYPES, bp);
/*
* xfs_bmap_finish() may commit the current transaction and
* start a second transaction if the freelist is not empty.
*
* Since we still want to modify this buffer, we need to
* ensure that the buffer is not released on commit of
* the first transaction and ensure the buffer is added to the
* second transaction.
*
* If there is only one transaction then don't stop the buffer
* from being released when it commits later on.
*/
xfs_trans_bhold(tp, bp);
if ((error = xfs_bmap_finish(tpp, &flist, &committed))) {
goto error1;
}
if (committed) {
tp = *tpp;
xfs_trans_bjoin(tp, bp);
} else {
xfs_trans_bhold_release(tp, bp);
}
*O_bpp = bp;
return 0;
error1:
xfs_bmap_cancel(&flist);
error0:
xfs_iunlock(quotip, XFS_ILOCK_EXCL);
return (error);
}
/*
* Return the dquot for a given inode and type. If @can_alloc is true, then
* allocate blocks if needed. The inode's ILOCK must be held and it must not
* have already had an inode attached.
*/
int
xfs_qm_dqget_inode(
struct xfs_inode *ip,
uint type,
bool can_alloc,
struct xfs_dquot **O_dqpp)
{
struct xfs_mount *mp = ip->i_mount;
struct xfs_quotainfo *qi = mp->m_quotainfo;
struct radix_tree_root *tree = xfs_dquot_tree(qi, type);
struct xfs_dquot *dqp;
xfs_dqid_t id;
int error;
error = xfs_qm_dqget_checks(mp, type);
if (error)
return error;
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
ASSERT(xfs_inode_dquot(ip, type) == NULL);
id = xfs_qm_id_for_quotatype(ip, type);
restart:
dqp = xfs_qm_dqget_cache_lookup(mp, qi, tree, id);
if (dqp) {
*O_dqpp = dqp;
return 0;
}
/*
* Dquot cache miss. We don't want to keep the inode lock across
* a (potential) disk read. Also we don't want to deal with the lock
* ordering between quotainode and this inode. OTOH, dropping the inode
* lock here means dealing with a chown that can happen before
* we re-acquire the lock.
*/
xfs_iunlock(ip, XFS_ILOCK_EXCL);
error = xfs_qm_dqread(mp, id, type, can_alloc, &dqp);
xfs_ilock(ip, XFS_ILOCK_EXCL);
if (error)
return error;
/*
* A dquot could be attached to this inode by now, since we had
* dropped the ilock.
*/
if (xfs_this_quota_on(mp, type)) {
struct xfs_dquot *dqp1;
dqp1 = xfs_inode_dquot(ip, type);
if (dqp1) {
xfs_qm_dqdestroy(dqp);
dqp = dqp1;
xfs_dqlock(dqp);
goto dqret;
}
} else {
/* inode stays locked on return */
xfs_qm_dqdestroy(dqp);
return -ESRCH;
}
error = xfs_qm_dqget_cache_insert(mp, qi, tree, id, dqp);
if (error) {
/*
* Duplicate found. Just throw away the new dquot and start
* over.
*/
xfs_qm_dqdestroy(dqp);
XFS_STATS_INC(mp, xs_qm_dquot_dups);
goto restart;
}
dqret:
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
trace_xfs_dqget_miss(dqp);
*O_dqpp = dqp;
return 0;
}
/*
* Ensure that the given in-core dquot has a buffer on disk backing it, and
* return the buffer locked and held. This is called when the bmapi finds a
* hole.
*/
STATIC int
xfs_dquot_disk_alloc(
struct xfs_trans **tpp,
struct xfs_dquot *dqp,
struct xfs_buf **bpp)
{
struct xfs_bmbt_irec map;
struct xfs_trans *tp = *tpp;
struct xfs_mount *mp = tp->t_mountp;
struct xfs_buf *bp;
struct xfs_inode *quotip = xfs_quota_inode(mp, dqp->dq_flags);
int nmaps = 1;
int error;
trace_xfs_dqalloc(dqp);
xfs_ilock(quotip, XFS_ILOCK_EXCL);
if (!xfs_this_quota_on(dqp->q_mount, dqp->dq_flags)) {
/*
* Return if this type of quotas is turned off while we didn't
* have an inode lock
*/
xfs_iunlock(quotip, XFS_ILOCK_EXCL);
return -ESRCH;
}
/* Create the block mapping. */
xfs_trans_ijoin(tp, quotip, XFS_ILOCK_EXCL);
error = xfs_bmapi_write(tp, quotip, dqp->q_fileoffset,
XFS_DQUOT_CLUSTER_SIZE_FSB, XFS_BMAPI_METADATA,
XFS_QM_DQALLOC_SPACE_RES(mp), &map, &nmaps);
if (error)
return error;
ASSERT(map.br_blockcount == XFS_DQUOT_CLUSTER_SIZE_FSB);
ASSERT(nmaps == 1);
ASSERT((map.br_startblock != DELAYSTARTBLOCK) &&
(map.br_startblock != HOLESTARTBLOCK));
/*
* Keep track of the blkno to save a lookup later
*/
dqp->q_blkno = XFS_FSB_TO_DADDR(mp, map.br_startblock);
/* now we can just get the buffer (there's nothing to read yet) */
bp = xfs_trans_get_buf(tp, mp->m_ddev_targp, dqp->q_blkno,
mp->m_quotainfo->qi_dqchunklen, 0);
if (!bp)
return -ENOMEM;
bp->b_ops = &xfs_dquot_buf_ops;
/*
* Make a chunk of dquots out of this buffer and log
* the entire thing.
*/
xfs_qm_init_dquot_blk(tp, mp, be32_to_cpu(dqp->q_core.d_id),
dqp->dq_flags & XFS_DQ_ALLTYPES, bp);
xfs_buf_set_ref(bp, XFS_DQUOT_REF);
/*
* Hold the buffer and join it to the dfops so that we'll still own
* the buffer when we return to the caller. The buffer disposal on
* error must be paid attention to very carefully, as it has been
* broken since commit efa092f3d4c6 "[XFS] Fixes a bug in the quota
* code when allocating a new dquot record" in 2005, and the later
* conversion to xfs_defer_ops in commit 310a75a3c6c747 failed to keep
* the buffer locked across the _defer_finish call. We can now do
* this correctly with xfs_defer_bjoin.
*
* Above, we allocated a disk block for the dquot information and used
* get_buf to initialize the dquot. If the _defer_finish fails, the old
* transaction is gone but the new buffer is not joined or held to any
* transaction, so we must _buf_relse it.
*
* If everything succeeds, the caller of this function is returned a
* buffer that is locked and held to the transaction. The caller
* is responsible for unlocking any buffer passed back, either
* manually or by committing the transaction. On error, the buffer is
* released and not passed back.
*/
xfs_trans_bhold(tp, bp);
error = xfs_defer_finish(tpp);
if (error) {
xfs_trans_bhold_release(*tpp, bp);
xfs_trans_brelse(*tpp, bp);
return error;
}
*bpp = bp;
return 0;
}
/*
* Maps a dquot to the buffer containing its on-disk version.
* This returns a ptr to the buffer containing the on-disk dquot
* in the bpp param, and a ptr to the on-disk dquot within that buffer
*/
STATIC int
xfs_qm_dqtobp(
xfs_trans_t **tpp,
xfs_dquot_t *dqp,
xfs_disk_dquot_t **O_ddpp,
xfs_buf_t **O_bpp,
uint flags)
{
xfs_bmbt_irec_t map;
int nmaps = 1, error;
xfs_buf_t *bp;
xfs_inode_t *quotip = XFS_DQ_TO_QIP(dqp);
xfs_mount_t *mp = dqp->q_mount;
xfs_disk_dquot_t *ddq;
xfs_dqid_t id = be32_to_cpu(dqp->q_core.d_id);
xfs_trans_t *tp = (tpp ? *tpp : NULL);
dqp->q_fileoffset = (xfs_fileoff_t)id / mp->m_quotainfo->qi_dqperchunk;
xfs_ilock(quotip, XFS_ILOCK_SHARED);
if (!xfs_this_quota_on(dqp->q_mount, dqp->dq_flags)) {
/*
* Return if this type of quotas is turned off while we
* didn't have the quota inode lock.
*/
xfs_iunlock(quotip, XFS_ILOCK_SHARED);
return ESRCH;
}
/*
* Find the block map; no allocations yet
*/
error = xfs_bmapi_read(quotip, dqp->q_fileoffset,
XFS_DQUOT_CLUSTER_SIZE_FSB, &map, &nmaps, 0);
xfs_iunlock(quotip, XFS_ILOCK_SHARED);
if (error)
return error;
ASSERT(nmaps == 1);
ASSERT(map.br_blockcount == 1);
/*
* Offset of dquot in the (fixed sized) dquot chunk.
*/
dqp->q_bufoffset = (id % mp->m_quotainfo->qi_dqperchunk) *
sizeof(xfs_dqblk_t);
ASSERT(map.br_startblock != DELAYSTARTBLOCK);
if (map.br_startblock == HOLESTARTBLOCK) {
/*
* We don't allocate unless we're asked to
*/
if (!(flags & XFS_QMOPT_DQALLOC))
return ENOENT;
ASSERT(tp);
error = xfs_qm_dqalloc(tpp, mp, dqp, quotip,
dqp->q_fileoffset, &bp);
if (error)
return error;
tp = *tpp;
} else {
trace_xfs_dqtobp_read(dqp);
/*
* store the blkno etc so that we don't have to do the
* mapping all the time
*/
dqp->q_blkno = XFS_FSB_TO_DADDR(mp, map.br_startblock);
error = xfs_trans_read_buf(mp, tp, mp->m_ddev_targp,
dqp->q_blkno,
mp->m_quotainfo->qi_dqchunklen,
0, &bp);
if (error || !bp)
return XFS_ERROR(error);
}
ASSERT(xfs_buf_islocked(bp));
/*
* calculate the location of the dquot inside the buffer.
*/
ddq = bp->b_addr + dqp->q_bufoffset;
/*
* A simple sanity check in case we got a corrupted dquot...
*/
error = xfs_qm_dqcheck(mp, ddq, id, dqp->dq_flags & XFS_DQ_ALLTYPES,
flags & (XFS_QMOPT_DQREPAIR|XFS_QMOPT_DOWARN),
"dqtobp");
if (error) {
if (!(flags & XFS_QMOPT_DQREPAIR)) {
xfs_trans_brelse(tp, bp);
return XFS_ERROR(EIO);
}
}
*O_bpp = bp;
*O_ddpp = ddq;
return (0);
}
