diff options
Diffstat (limited to 'fs/xfs/xfs_reflink.c')
-rw-r--r-- | fs/xfs/xfs_reflink.c | 394 |
1 files changed, 259 insertions, 135 deletions
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c index d5ca8bcae65b..59f7fc16eb80 100644 --- a/fs/xfs/xfs_reflink.c +++ b/fs/xfs/xfs_reflink.c @@ -29,6 +29,11 @@ #include "xfs_iomap.h" #include "xfs_ag.h" #include "xfs_ag_resv.h" +#include "xfs_health.h" +#include "xfs_rtrefcount_btree.h" +#include "xfs_rtalloc.h" +#include "xfs_rtgroup.h" +#include "xfs_metafile.h" /* * Copy on Write of Shared Blocks @@ -119,38 +124,93 @@ */ /* - * Given an AG extent, find the lowest-numbered run of shared blocks - * within that range and return the range in fbno/flen. If - * find_end_of_shared is true, return the longest contiguous extent of - * shared blocks. If there are no shared extents, fbno and flen will - * be set to NULLAGBLOCK and 0, respectively. + * Given a file mapping for the data device, find the lowest-numbered run of + * shared blocks within that mapping and return it in shared_offset/shared_len. + * The offset is relative to the start of irec. + * + * If find_end_of_shared is true, return the longest contiguous extent of shared + * blocks. If there are no shared extents, shared_offset and shared_len will be + * set to 0; */ static int xfs_reflink_find_shared( - struct xfs_perag *pag, + struct xfs_mount *mp, struct xfs_trans *tp, - xfs_agblock_t agbno, - xfs_extlen_t aglen, - xfs_agblock_t *fbno, - xfs_extlen_t *flen, + const struct xfs_bmbt_irec *irec, + xfs_extlen_t *shared_offset, + xfs_extlen_t *shared_len, bool find_end_of_shared) { struct xfs_buf *agbp; + struct xfs_perag *pag; struct xfs_btree_cur *cur; int error; + xfs_agblock_t orig_bno, found_bno; + + pag = xfs_perag_get(mp, XFS_FSB_TO_AGNO(mp, irec->br_startblock)); + orig_bno = XFS_FSB_TO_AGBNO(mp, irec->br_startblock); error = xfs_alloc_read_agf(pag, tp, 0, &agbp); if (error) - return error; + goto out; - cur = xfs_refcountbt_init_cursor(pag->pag_mount, tp, agbp, pag); + cur = xfs_refcountbt_init_cursor(mp, tp, agbp, pag); + error = xfs_refcount_find_shared(cur, orig_bno, irec->br_blockcount, + &found_bno, shared_len, find_end_of_shared); + xfs_btree_del_cursor(cur, error); + xfs_trans_brelse(tp, agbp); - error = xfs_refcount_find_shared(cur, agbno, aglen, fbno, flen, - find_end_of_shared); + if (!error && *shared_len) + *shared_offset = found_bno - orig_bno; +out: + xfs_perag_put(pag); + return error; +} +/* + * Given a file mapping for the rt device, find the lowest-numbered run of + * shared blocks within that mapping and return it in shared_offset/shared_len. + * The offset is relative to the start of irec. + * + * If find_end_of_shared is true, return the longest contiguous extent of shared + * blocks. If there are no shared extents, shared_offset and shared_len will be + * set to 0; + */ +static int +xfs_reflink_find_rtshared( + struct xfs_mount *mp, + struct xfs_trans *tp, + const struct xfs_bmbt_irec *irec, + xfs_extlen_t *shared_offset, + xfs_extlen_t *shared_len, + bool find_end_of_shared) +{ + struct xfs_rtgroup *rtg; + struct xfs_btree_cur *cur; + xfs_rgblock_t orig_bno; + xfs_agblock_t found_bno; + int error; + + BUILD_BUG_ON(NULLRGBLOCK != NULLAGBLOCK); + + /* + * Note: this uses the not quite correct xfs_agblock_t type because + * xfs_refcount_find_shared is shared between the RT and data device + * refcount code. + */ + orig_bno = xfs_rtb_to_rgbno(mp, irec->br_startblock); + rtg = xfs_rtgroup_get(mp, xfs_rtb_to_rgno(mp, irec->br_startblock)); + + xfs_rtgroup_lock(rtg, XFS_RTGLOCK_REFCOUNT); + cur = xfs_rtrefcountbt_init_cursor(tp, rtg); + error = xfs_refcount_find_shared(cur, orig_bno, irec->br_blockcount, + &found_bno, shared_len, find_end_of_shared); xfs_btree_del_cursor(cur, error); + xfs_rtgroup_unlock(rtg, XFS_RTGLOCK_REFCOUNT); + xfs_rtgroup_put(rtg); - xfs_trans_brelse(tp, agbp); + if (!error && *shared_len) + *shared_offset = found_bno - orig_bno; return error; } @@ -171,11 +231,7 @@ xfs_reflink_trim_around_shared( bool *shared) { struct xfs_mount *mp = ip->i_mount; - struct xfs_perag *pag; - xfs_agblock_t agbno; - xfs_extlen_t aglen; - xfs_agblock_t fbno; - xfs_extlen_t flen; + xfs_extlen_t shared_offset, shared_len; int error = 0; /* Holes, unwritten, and delalloc extents cannot be shared */ @@ -186,41 +242,37 @@ xfs_reflink_trim_around_shared( trace_xfs_reflink_trim_around_shared(ip, irec); - pag = xfs_perag_get(mp, XFS_FSB_TO_AGNO(mp, irec->br_startblock)); - agbno = XFS_FSB_TO_AGBNO(mp, irec->br_startblock); - aglen = irec->br_blockcount; - - error = xfs_reflink_find_shared(pag, NULL, agbno, aglen, &fbno, &flen, - true); - xfs_perag_put(pag); + if (XFS_IS_REALTIME_INODE(ip)) + error = xfs_reflink_find_rtshared(mp, NULL, irec, + &shared_offset, &shared_len, true); + else + error = xfs_reflink_find_shared(mp, NULL, irec, + &shared_offset, &shared_len, true); if (error) return error; - *shared = false; - if (fbno == NULLAGBLOCK) { + if (!shared_len) { /* No shared blocks at all. */ - return 0; - } - - if (fbno == agbno) { + *shared = false; + } else if (!shared_offset) { /* - * The start of this extent is shared. Truncate the - * mapping at the end of the shared region so that a - * subsequent iteration starts at the start of the - * unshared region. + * The start of this mapping points to shared space. Truncate + * the mapping at the end of the shared region so that a + * subsequent iteration starts at the start of the unshared + * region. */ - irec->br_blockcount = flen; + irec->br_blockcount = shared_len; *shared = true; - return 0; + } else { + /* + * There's a shared region that doesn't start at the beginning + * of the mapping. Truncate the mapping at the start of the + * shared extent so that a subsequent iteration starts at the + * start of the shared region. + */ + irec->br_blockcount = shared_offset; + *shared = false; } - - /* - * There's a shared extent midway through this extent. - * Truncate the mapping at the start of the shared - * extent so that a subsequent iteration starts at the - * start of the shared region. - */ - irec->br_blockcount = fbno - agbno; return 0; } @@ -388,20 +440,26 @@ xfs_reflink_fill_cow_hole( struct xfs_mount *mp = ip->i_mount; struct xfs_trans *tp; xfs_filblks_t resaligned; - xfs_extlen_t resblks; + unsigned int dblocks = 0, rblocks = 0; int nimaps; int error; bool found; resaligned = xfs_aligned_fsb_count(imap->br_startoff, imap->br_blockcount, xfs_get_cowextsz_hint(ip)); - resblks = XFS_DIOSTRAT_SPACE_RES(mp, resaligned); + if (XFS_IS_REALTIME_INODE(ip)) { + dblocks = XFS_DIOSTRAT_SPACE_RES(mp, 0); + rblocks = resaligned; + } else { + dblocks = XFS_DIOSTRAT_SPACE_RES(mp, resaligned); + rblocks = 0; + } xfs_iunlock(ip, *lockmode); *lockmode = 0; - error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, resblks, 0, - false, &tp); + error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, dblocks, + rblocks, false, &tp); if (error) return error; @@ -429,13 +487,6 @@ xfs_reflink_fill_cow_hole( if (error) return error; - /* - * Allocation succeeded but the requested range was not even partially - * satisfied? Bail out! - */ - if (nimaps == 0) - return -ENOSPC; - convert: return xfs_reflink_convert_unwritten(ip, imap, cmap, convert_now); @@ -498,13 +549,6 @@ xfs_reflink_fill_delalloc( error = xfs_trans_commit(tp); if (error) return error; - - /* - * Allocation succeeded but the requested range was not even - * partially satisfied? Bail out! - */ - if (nimaps == 0) - return -ENOSPC; } while (cmap->br_startoff + cmap->br_blockcount <= imap->br_startoff); return xfs_reflink_convert_unwritten(ip, imap, cmap, convert_now); @@ -527,7 +571,7 @@ xfs_reflink_allocate_cow( int error; bool found; - ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); + xfs_assert_ilocked(ip, XFS_ILOCK_EXCL); if (!ip->i_cowfp) { ASSERT(!xfs_is_reflink_inode(ip)); xfs_ifork_init_cow(ip); @@ -584,6 +628,7 @@ xfs_reflink_cancel_cow_blocks( struct xfs_ifork *ifp = xfs_ifork_ptr(ip, XFS_COW_FORK); struct xfs_bmbt_irec got, del; struct xfs_iext_cursor icur; + bool isrt = XFS_IS_REALTIME_INODE(ip); int error = 0; if (!xfs_inode_has_cow_data(ip)) @@ -605,20 +650,19 @@ xfs_reflink_cancel_cow_blocks( trace_xfs_reflink_cancel_cow(ip, &del); if (isnullstartblock(del.br_startblock)) { - error = xfs_bmap_del_extent_delay(ip, XFS_COW_FORK, - &icur, &got, &del); - if (error) - break; + xfs_bmap_del_extent_delay(ip, XFS_COW_FORK, &icur, &got, + &del); } else if (del.br_state == XFS_EXT_UNWRITTEN || cancel_real) { ASSERT((*tpp)->t_highest_agno == NULLAGNUMBER); /* Free the CoW orphan record. */ - xfs_refcount_free_cow_extent(*tpp, del.br_startblock, - del.br_blockcount); + xfs_refcount_free_cow_extent(*tpp, isrt, + del.br_startblock, del.br_blockcount); error = xfs_free_extent_later(*tpp, del.br_startblock, del.br_blockcount, NULL, - XFS_AG_RESV_NONE, false); + XFS_AG_RESV_NONE, + isrt ? XFS_FREE_EXTENT_REALTIME : 0); if (error) break; @@ -631,10 +675,7 @@ xfs_reflink_cancel_cow_blocks( xfs_bmap_del_extent_cow(ip, &icur, &got, &del); /* Remove the quota reservation */ - error = xfs_quota_unreserve_blkres(ip, - del.br_blockcount); - if (error) - break; + xfs_quota_unreserve_blkres(ip, del.br_blockcount); } else { /* Didn't do anything, push cursor back. */ xfs_iext_prev(ifp, &icur); @@ -705,6 +746,35 @@ out: return error; } +#ifdef CONFIG_XFS_QUOTA +/* + * Update quota accounting for a remapping operation. When we're remapping + * something from the CoW fork to the data fork, we must update the quota + * accounting for delayed allocations. For remapping from the data fork to the + * data fork, use regular block accounting. + */ +static inline void +xfs_reflink_update_quota( + struct xfs_trans *tp, + struct xfs_inode *ip, + bool is_cow, + int64_t blocks) +{ + unsigned int qflag; + + if (XFS_IS_REALTIME_INODE(ip)) { + qflag = is_cow ? XFS_TRANS_DQ_DELRTBCOUNT : + XFS_TRANS_DQ_RTBCOUNT; + } else { + qflag = is_cow ? XFS_TRANS_DQ_DELBCOUNT : + XFS_TRANS_DQ_BCOUNT; + } + xfs_trans_mod_dquot_byino(tp, ip, qflag, blocks); +} +#else +# define xfs_reflink_update_quota(tp, ip, is_cow, blocks) ((void)0) +#endif + /* * Remap part of the CoW fork into the data fork. * @@ -728,14 +798,9 @@ xfs_reflink_end_cow_extent( struct xfs_ifork *ifp = xfs_ifork_ptr(ip, XFS_COW_FORK); unsigned int resblks; int nmaps; + bool isrt = XFS_IS_REALTIME_INODE(ip); int error; - /* No COW extents? That's easy! */ - if (ifp->if_bytes == 0) { - *offset_fsb = end_fsb; - return 0; - } - resblks = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK); error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, XFS_TRANS_RESERVE, &tp); @@ -750,14 +815,6 @@ xfs_reflink_end_cow_extent( xfs_ilock(ip, XFS_ILOCK_EXCL); xfs_trans_ijoin(tp, ip, 0); - error = xfs_iext_count_may_overflow(ip, XFS_DATA_FORK, - XFS_IEXT_REFLINK_END_COW_CNT); - if (error == -EFBIG) - error = xfs_iext_count_upgrade(tp, ip, - XFS_IEXT_REFLINK_END_COW_CNT); - if (error) - goto out_cancel; - /* * 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 @@ -786,6 +843,11 @@ xfs_reflink_end_cow_extent( del = got; xfs_trim_extent(&del, *offset_fsb, end_fsb - *offset_fsb); + error = xfs_iext_count_extend(tp, ip, XFS_DATA_FORK, + XFS_IEXT_REFLINK_END_COW_CNT); + if (error) + goto out_cancel; + /* Grab the corresponding mapping in the data fork. */ nmaps = 1; error = xfs_bmapi_read(ip, del.br_startoff, del.br_blockcount, &data, @@ -805,10 +867,9 @@ xfs_reflink_end_cow_extent( * If the extent we're remapping is backed by storage (written * or not), unmap the extent and drop its refcount. */ - xfs_bmap_unmap_extent(tp, ip, &data); - xfs_refcount_decrease_extent(tp, &data); - xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, - -data.br_blockcount); + xfs_bmap_unmap_extent(tp, ip, XFS_DATA_FORK, &data); + xfs_refcount_decrease_extent(tp, isrt, &data); + xfs_reflink_update_quota(tp, ip, false, -data.br_blockcount); } else if (data.br_startblock == DELAYSTARTBLOCK) { int done; @@ -826,14 +887,14 @@ xfs_reflink_end_cow_extent( } /* Free the CoW orphan record. */ - xfs_refcount_free_cow_extent(tp, del.br_startblock, del.br_blockcount); + xfs_refcount_free_cow_extent(tp, isrt, del.br_startblock, + del.br_blockcount); /* Map the new blocks into the data fork. */ - xfs_bmap_map_extent(tp, ip, &del); + xfs_bmap_map_extent(tp, ip, XFS_DATA_FORK, &del); /* Charge this new data fork mapping to the on-disk quota. */ - xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_DELBCOUNT, - (long)del.br_blockcount); + xfs_reflink_update_quota(tp, ip, true, del.br_blockcount); /* Remove the mapping from the CoW fork. */ xfs_bmap_del_extent_cow(ip, &icur, &got, &del); @@ -921,22 +982,30 @@ int xfs_reflink_recover_cow( struct xfs_mount *mp) { - struct xfs_perag *pag; - xfs_agnumber_t agno; + struct xfs_perag *pag = NULL; + struct xfs_rtgroup *rtg = NULL; int error = 0; if (!xfs_has_reflink(mp)) return 0; - for_each_perag(mp, agno, pag) { - error = xfs_refcount_recover_cow_leftovers(mp, pag); + while ((pag = xfs_perag_next(mp, pag))) { + error = xfs_refcount_recover_cow_leftovers(pag_group(pag)); if (error) { xfs_perag_rele(pag); - break; + return error; } } - return error; + while ((rtg = xfs_rtgroup_next(mp, rtg))) { + error = xfs_refcount_recover_cow_leftovers(rtg_group(rtg)); + if (error) { + xfs_rtgroup_rele(rtg); + return error; + } + } + + return 0; } /* @@ -1128,14 +1197,28 @@ out_error: static int xfs_reflink_ag_has_free_space( struct xfs_mount *mp, - xfs_agnumber_t agno) + struct xfs_inode *ip, + xfs_fsblock_t fsb) { struct xfs_perag *pag; + xfs_agnumber_t agno; int error = 0; if (!xfs_has_rmapbt(mp)) return 0; + if (XFS_IS_REALTIME_INODE(ip)) { + struct xfs_rtgroup *rtg; + xfs_rgnumber_t rgno; + + rgno = xfs_rtb_to_rgno(mp, fsb); + rtg = xfs_rtgroup_get(mp, rgno); + if (xfs_metafile_resv_critical(rtg_rmap(rtg))) + error = -ENOSPC; + xfs_rtgroup_put(rtg); + return error; + } + agno = XFS_FSB_TO_AGNO(mp, fsb); pag = xfs_perag_get(mp, agno); if (xfs_ag_resv_critical(pag, XFS_AG_RESV_RMAPBT) || xfs_ag_resv_critical(pag, XFS_AG_RESV_METADATA)) @@ -1159,10 +1242,11 @@ xfs_reflink_remap_extent( struct xfs_trans *tp; xfs_off_t newlen; int64_t qdelta = 0; - unsigned int resblks; + unsigned int dblocks, rblocks, resblks; bool quota_reserved = true; bool smap_real; bool dmap_written = xfs_bmap_is_written_extent(dmap); + bool isrt = XFS_IS_REALTIME_INODE(ip); int iext_delta = 0; int nimaps; int error; @@ -1189,8 +1273,15 @@ xfs_reflink_remap_extent( * we're remapping. */ resblks = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK); + if (XFS_IS_REALTIME_INODE(ip)) { + dblocks = resblks; + rblocks = dmap->br_blockcount; + } else { + dblocks = resblks + dmap->br_blockcount; + rblocks = 0; + } error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, - resblks + dmap->br_blockcount, 0, false, &tp); + dblocks, rblocks, false, &tp); if (error == -EDQUOT || error == -ENOSPC) { quota_reserved = false; error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, @@ -1227,8 +1318,10 @@ xfs_reflink_remap_extent( * extent if they're both holes or both the same physical extent. */ if (dmap->br_startblock == smap.br_startblock) { - if (dmap->br_state != smap.br_state) + if (dmap->br_state != smap.br_state) { + xfs_bmap_mark_sick(ip, XFS_DATA_FORK); error = -EFSCORRUPTED; + } goto out_cancel; } @@ -1239,8 +1332,8 @@ xfs_reflink_remap_extent( /* No reflinking if the AG of the dest mapping is low on space. */ if (dmap_written) { - error = xfs_reflink_ag_has_free_space(mp, - XFS_FSB_TO_AGNO(mp, dmap->br_startblock)); + error = xfs_reflink_ag_has_free_space(mp, ip, + dmap->br_startblock); if (error) goto out_cancel; } @@ -1268,8 +1361,15 @@ xfs_reflink_remap_extent( * done. */ if (!quota_reserved && !smap_real && dmap_written) { - error = xfs_trans_reserve_quota_nblks(tp, ip, - dmap->br_blockcount, 0, false); + if (XFS_IS_REALTIME_INODE(ip)) { + dblocks = 0; + rblocks = dmap->br_blockcount; + } else { + dblocks = dmap->br_blockcount; + rblocks = 0; + } + error = xfs_trans_reserve_quota_nblks(tp, ip, dblocks, rblocks, + false); if (error) goto out_cancel; } @@ -1280,9 +1380,7 @@ xfs_reflink_remap_extent( if (dmap_written) ++iext_delta; - error = xfs_iext_count_may_overflow(ip, XFS_DATA_FORK, iext_delta); - if (error == -EFBIG) - error = xfs_iext_count_upgrade(tp, ip, iext_delta); + error = xfs_iext_count_extend(tp, ip, XFS_DATA_FORK, iext_delta); if (error) goto out_cancel; @@ -1291,8 +1389,8 @@ xfs_reflink_remap_extent( * If the extent we're unmapping is backed by storage (written * or not), unmap the extent and drop its refcount. */ - xfs_bmap_unmap_extent(tp, ip, &smap); - xfs_refcount_decrease_extent(tp, &smap); + xfs_bmap_unmap_extent(tp, ip, XFS_DATA_FORK, &smap); + xfs_refcount_decrease_extent(tp, isrt, &smap); qdelta -= smap.br_blockcount; } else if (smap.br_startblock == DELAYSTARTBLOCK) { int done; @@ -1315,12 +1413,12 @@ xfs_reflink_remap_extent( * its refcount and map it into the file. */ if (dmap_written) { - xfs_refcount_increase_extent(tp, dmap); - xfs_bmap_map_extent(tp, ip, dmap); + xfs_refcount_increase_extent(tp, isrt, dmap); + xfs_bmap_map_extent(tp, ip, XFS_DATA_FORK, dmap); qdelta += dmap->br_blockcount; } - xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, qdelta); + xfs_reflink_update_quota(tp, ip, false, qdelta); /* Update dest isize if needed. */ newlen = XFS_FSB_TO_B(mp, dmap->br_startoff + dmap->br_blockcount); @@ -1391,6 +1489,7 @@ xfs_reflink_remap_blocks( ASSERT(nimaps == 1 && imap.br_startoff == srcoff); if (imap.br_startblock == DELAYSTARTBLOCK) { ASSERT(imap.br_startblock != DELAYSTARTBLOCK); + xfs_bmap_mark_sick(src, XFS_DATA_FORK); error = -EFSCORRUPTED; break; } @@ -1413,6 +1512,7 @@ xfs_reflink_remap_blocks( destoff += imap.br_blockcount; len -= imap.br_blockcount; remapped_len += imap.br_blockcount; + cond_resched(); } if (error) @@ -1492,8 +1592,8 @@ xfs_reflink_remap_prep( /* Check file eligibility and prepare for block sharing. */ ret = -EINVAL; - /* Don't reflink realtime inodes */ - if (XFS_IS_REALTIME_INODE(src) || XFS_IS_REALTIME_INODE(dest)) + /* Can't reflink between data and rt volumes */ + if (XFS_IS_REALTIME_INODE(src) != XFS_IS_REALTIME_INODE(dest)) goto out_unlock; /* Don't share DAX file data with non-DAX file. */ @@ -1573,27 +1673,23 @@ xfs_reflink_inode_has_shared_extents( *has_shared = false; found = xfs_iext_lookup_extent(ip, ifp, 0, &icur, &got); while (found) { - struct xfs_perag *pag; - xfs_agblock_t agbno; - xfs_extlen_t aglen; - xfs_agblock_t rbno; - xfs_extlen_t rlen; + xfs_extlen_t shared_offset, shared_len; if (isnullstartblock(got.br_startblock) || got.br_state != XFS_EXT_NORM) goto next; - pag = xfs_perag_get(mp, XFS_FSB_TO_AGNO(mp, got.br_startblock)); - agbno = XFS_FSB_TO_AGBNO(mp, got.br_startblock); - aglen = got.br_blockcount; - error = xfs_reflink_find_shared(pag, tp, agbno, aglen, - &rbno, &rlen, false); - xfs_perag_put(pag); + if (XFS_IS_REALTIME_INODE(ip)) + error = xfs_reflink_find_rtshared(mp, tp, &got, + &shared_offset, &shared_len, false); + else + error = xfs_reflink_find_shared(mp, tp, &got, + &shared_offset, &shared_len, false); if (error) return error; /* Is there still a shared block here? */ - if (rbno != NULLAGBLOCK) { + if (shared_len) { *has_shared = true; return 0; } @@ -1620,6 +1716,9 @@ xfs_reflink_clear_inode_flag( ASSERT(xfs_is_reflink_inode(ip)); + if (!xfs_can_free_cowblocks(ip)) + return 0; + error = xfs_reflink_inode_has_shared_extents(*tpp, ip, &needs_flag); if (error || needs_flag) return error; @@ -1723,3 +1822,28 @@ out: trace_xfs_reflink_unshare_error(ip, error, _RET_IP_); return error; } + +/* + * Can we use reflink with this realtime extent size? Note that we don't check + * for rblocks > 0 here because this can be called as part of attaching a new + * rt section. + */ +bool +xfs_reflink_supports_rextsize( + struct xfs_mount *mp, + unsigned int rextsize) +{ + /* reflink on the realtime device requires rtgroups */ + if (!xfs_has_rtgroups(mp)) + return false; + + /* + * Reflink doesn't support rt extent size larger than a single fsblock + * because we would have to perform CoW-around for unaligned write + * requests to guarantee that we always remap entire rt extents. + */ + if (rextsize != 1) + return false; + + return true; +} |