/*
* Calculate how many blocks we need for the new attribute,
*/
STATIC int
xfs_attr_calc_size(
struct xfs_da_args *args,
int *local)
{
struct xfs_mount *mp = args->dp->i_mount;
int size;
int nblks;
/*
* Determine space new attribute will use, and if it would be
* "local" or "remote" (note: local != inline).
*/
size = xfs_attr_leaf_newentsize(args, local);
nblks = XFS_DAENTER_SPACE_RES(mp, XFS_ATTR_FORK);
if (*local) {
if (size > (args->geo->blksize / 2)) {
/* Double split possible */
nblks *= 2;
}
} else {
/*
* Out of line attribute, cannot double split, but
* make room for the attribute value itself.
*/
uint dblocks = xfs_attr3_rmt_blocks(mp, args->valuelen);
nblks += dblocks;
nblks += XFS_NEXTENTADD_SPACE_RES(mp, dblocks, XFS_ATTR_FORK);
}
return nblks;
}
/*
* Calculate the maximum length in bytes that would be required for a local
* attribute value as large attributes out of line are not logged.
*/
STATIC int
xfs_log_calc_max_attrsetm_res(
struct xfs_mount *mp)
{
int size;
int nblks;
size = xfs_attr_leaf_entsize_local_max(mp->m_sb.sb_blocksize) -
MAXNAMELEN - 1;
nblks = XFS_DAENTER_SPACE_RES(mp, XFS_ATTR_FORK);
nblks += XFS_B_TO_FSB(mp, size);
nblks += XFS_NEXTENTADD_SPACE_RES(mp, size, XFS_ATTR_FORK);
return M_RES(mp)->tr_attrsetm.tr_logres +
M_RES(mp)->tr_attrsetrt.tr_logres * nblks;
}
/*
* Remap parts of a file's data fork after a successful CoW.
*/
int
xfs_reflink_end_cow(
struct xfs_inode *ip,
xfs_off_t offset,
xfs_off_t count)
{
struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
struct xfs_bmbt_irec got, del;
struct xfs_trans *tp;
xfs_fileoff_t offset_fsb;
xfs_fileoff_t end_fsb;
xfs_fsblock_t firstfsb;
struct xfs_defer_ops dfops;
int error;
unsigned int resblks;
xfs_filblks_t rlen;
xfs_extnum_t idx;
trace_xfs_reflink_end_cow(ip, offset, count);
/* No COW extents? That's easy! */
if (ifp->if_bytes == 0)
return 0;
offset_fsb = XFS_B_TO_FSBT(ip->i_mount, offset);
end_fsb = XFS_B_TO_FSB(ip->i_mount, offset + count);
/*
* Start a rolling transaction to switch the mappings. We're
* unlikely ever to have to remap 16T worth of single-block
* extents, so just cap the worst case extent count to 2^32-1.
* Stick a warning in just in case, and avoid 64-bit division.
*/
BUILD_BUG_ON(MAX_RW_COUNT > UINT_MAX);
if (end_fsb - offset_fsb > UINT_MAX) {
error = -EFSCORRUPTED;
xfs_force_shutdown(ip->i_mount, SHUTDOWN_CORRUPT_INCORE);
ASSERT(0);
goto out;
}
resblks = XFS_NEXTENTADD_SPACE_RES(ip->i_mount,
(unsigned int)(end_fsb - offset_fsb),
XFS_DATA_FORK);
error = xfs_trans_alloc(ip->i_mount, &M_RES(ip->i_mount)->tr_write,
resblks, 0, 0, &tp);
if (error)
goto out;
xfs_ilock(ip, XFS_ILOCK_EXCL);
xfs_trans_ijoin(tp, ip, 0);
/* If there is a hole at end_fsb - 1 go to the previous extent */
if (!xfs_iext_lookup_extent(ip, ifp, end_fsb - 1, &idx, &got) ||
got.br_startoff > end_fsb) {
/*
* In case of racing, overlapping AIO writes no COW extents
* might be left by the time I/O completes for the loser of
* the race. In that case we are done.
*/
if (idx <= 0)
goto out_cancel;
xfs_iext_get_extent(ifp, --idx, &got);
}
/* Walk backwards until we're out of the I/O range... */
while (got.br_startoff + got.br_blockcount > offset_fsb) {
del = got;
xfs_trim_extent(&del, offset_fsb, end_fsb - offset_fsb);
/* Extent delete may have bumped idx forward */
if (!del.br_blockcount) {
idx--;
goto next_extent;
}
ASSERT(!isnullstartblock(got.br_startblock));
/*
* Don't remap unwritten extents; these are
* speculatively preallocated CoW extents that have been
* allocated but have not yet been involved in a write.
*/
if (got.br_state == XFS_EXT_UNWRITTEN) {
idx--;
goto next_extent;
}
/* Unmap the old blocks in the data fork. */
xfs_defer_init(&dfops, &firstfsb);
rlen = del.br_blockcount;
error = __xfs_bunmapi(tp, ip, del.br_startoff, &rlen, 0, 1,
&firstfsb, &dfops);
if (error)
goto out_defer;
/* Trim the extent to whatever got unmapped. */
if (rlen) {
xfs_trim_extent(&del, del.br_startoff + rlen,
del.br_blockcount - rlen);
}
trace_xfs_reflink_cow_remap(ip, &del);
/* Free the CoW orphan record. */
error = xfs_refcount_free_cow_extent(tp->t_mountp, &dfops,
del.br_startblock, del.br_blockcount);
if (error)
goto out_defer;
/* Map the new blocks into the data fork. */
error = xfs_bmap_map_extent(tp->t_mountp, &dfops, ip, &del);
if (error)
goto out_defer;
/* Remove the mapping from the CoW fork. */
xfs_bmap_del_extent_cow(ip, &idx, &got, &del);
xfs_defer_ijoin(&dfops, ip);
error = xfs_defer_finish(&tp, &dfops);
if (error)
goto out_defer;
next_extent:
if (!xfs_iext_get_extent(ifp, idx, &got))
break;
}
error = xfs_trans_commit(tp);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
if (error)
goto out;
return 0;
out_defer:
xfs_defer_cancel(&dfops);
out_cancel:
xfs_trans_cancel(tp);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
out:
trace_xfs_reflink_end_cow_error(ip, error, _RET_IP_);
return error;
}
static int
max_trans_res(
xfs_mount_t *mp,
int *mul)
{
uint *p;
uint *q;
int rval;
xfs_trans_reservations_t *tr;
xfs_da_args_t args;
int local;
int size;
int nblks;
int res;
nblks = XFS_DAENTER_SPACE_RES(mp, XFS_ATTR_FORK);
/*
* Fill in the arg structure for this request.
*/
bzero(&args, sizeof(args));
args.name = NULL;
args.namelen = MAXNAMELEN;
args.value = NULL;
args.valuelen = 65536;
args.flags = 0;
args.hashval = 0;
args.dp = NULL;
args.firstblock = NULL;
args.flist = NULL;
args.whichfork = XFS_ATTR_FORK;
args.oknoent = 1;
/*
* Determine space new attribute will use, and if it will be
* inline or out of line.
*/
size = libxfs_attr_leaf_newentsize(
&args, mp->m_sb.sb_blocksize, &local);
if (local) {
printf("Uh-oh.. attribute is local\n");
} else {
/* Out of line attribute, cannot double split, but make
* room for the attribute value itself.
*/
nblks += XFS_B_TO_FSB(mp, size);
nblks += XFS_NEXTENTADD_SPACE_RES(mp, size, XFS_ATTR_FORK);
}
res = XFS_ATTRSET_LOG_RES(mp, nblks);
#if 0
printf("size = %d nblks = %d res = %d\n", size, nblks, res);
#endif
mp->m_reservations.tr_attrset = res;
for (rval = 0, tr = &mp->m_reservations, p = (uint *)tr,
q = (uint *)&tr_count;
p < (uint *)(tr + 1);
p++, q++) {
if ((int)*p > rval) {
rval = (int)*p;
*mul = (int)*q;
}
}
return rval;
}
