diff options
Diffstat (limited to '')
-rw-r--r-- | fs/xfs/xfs_reflink.c | 839 |
1 files changed, 504 insertions, 335 deletions
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c index b0ce04ffd3cd..93bdd25680bc 100644 --- a/fs/xfs/xfs_reflink.c +++ b/fs/xfs/xfs_reflink.c @@ -27,7 +27,7 @@ #include "xfs_quota.h" #include "xfs_reflink.h" #include "xfs_iomap.h" -#include "xfs_sb.h" +#include "xfs_ag.h" #include "xfs_ag_resv.h" /* @@ -125,11 +125,10 @@ * shared blocks. If there are no shared extents, fbno and flen will * be set to NULLAGBLOCK and 0, respectively. */ -int +static int xfs_reflink_find_shared( - struct xfs_mount *mp, + struct xfs_perag *pag, struct xfs_trans *tp, - xfs_agnumber_t agno, xfs_agblock_t agbno, xfs_extlen_t aglen, xfs_agblock_t *fbno, @@ -140,11 +139,11 @@ xfs_reflink_find_shared( struct xfs_btree_cur *cur; int error; - error = xfs_alloc_read_agf(mp, tp, agno, 0, &agbp); + error = xfs_alloc_read_agf(pag, tp, 0, &agbp); if (error) return error; - cur = xfs_refcountbt_init_cursor(mp, tp, agbp, agno); + cur = xfs_refcountbt_init_cursor(pag->pag_mount, tp, agbp, pag); error = xfs_refcount_find_shared(cur, agbno, aglen, fbno, flen, find_end_of_shared); @@ -171,7 +170,8 @@ xfs_reflink_trim_around_shared( struct xfs_bmbt_irec *irec, bool *shared) { - xfs_agnumber_t agno; + struct xfs_mount *mp = ip->i_mount; + struct xfs_perag *pag; xfs_agblock_t agbno; xfs_extlen_t aglen; xfs_agblock_t fbno; @@ -179,19 +179,20 @@ xfs_reflink_trim_around_shared( int error = 0; /* Holes, unwritten, and delalloc extents cannot be shared */ - if (!xfs_is_cow_inode(ip) || !xfs_bmap_is_real_extent(irec)) { + if (!xfs_is_cow_inode(ip) || !xfs_bmap_is_written_extent(irec)) { *shared = false; return 0; } trace_xfs_reflink_trim_around_shared(ip, irec); - agno = XFS_FSB_TO_AGNO(ip->i_mount, irec->br_startblock); - agbno = XFS_FSB_TO_AGBNO(ip->i_mount, irec->br_startblock); + 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(ip->i_mount, NULL, agno, agbno, - aglen, &fbno, &flen, true); + error = xfs_reflink_find_shared(pag, NULL, agbno, aglen, &fbno, &flen, + true); + xfs_perag_put(pag); if (error) return error; @@ -199,7 +200,9 @@ xfs_reflink_trim_around_shared( if (fbno == NULLAGBLOCK) { /* No shared blocks at all. */ return 0; - } else if (fbno == agbno) { + } + + if (fbno == agbno) { /* * The start of this extent is shared. Truncate the * mapping at the end of the shared region so that a @@ -209,16 +212,16 @@ xfs_reflink_trim_around_shared( irec->br_blockcount = flen; *shared = true; return 0; - } else { - /* - * 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; } + + /* + * 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; } int @@ -340,9 +343,41 @@ xfs_find_trim_cow_extent( return 0; } -/* Allocate all CoW reservations covering a range of blocks in a file. */ -int -xfs_reflink_allocate_cow( +static int +xfs_reflink_convert_unwritten( + struct xfs_inode *ip, + struct xfs_bmbt_irec *imap, + struct xfs_bmbt_irec *cmap, + bool convert_now) +{ + xfs_fileoff_t offset_fsb = imap->br_startoff; + xfs_filblks_t count_fsb = imap->br_blockcount; + int error; + + /* + * cmap might larger than imap due to cowextsize hint. + */ + xfs_trim_extent(cmap, offset_fsb, count_fsb); + + /* + * COW fork extents are supposed to remain unwritten until we're ready + * to initiate a disk write. For direct I/O we are going to write the + * data and need the conversion, but for buffered writes we're done. + */ + if (!convert_now || cmap->br_state == XFS_EXT_NORM) + return 0; + + trace_xfs_reflink_convert_cow(ip, cmap); + + error = xfs_reflink_convert_cow_locked(ip, offset_fsb, count_fsb); + if (!error) + cmap->br_state = XFS_EXT_NORM; + + return error; +} + +static int +xfs_reflink_fill_cow_hole( struct xfs_inode *ip, struct xfs_bmbt_irec *imap, struct xfs_bmbt_irec *cmap, @@ -351,59 +386,37 @@ xfs_reflink_allocate_cow( bool convert_now) { struct xfs_mount *mp = ip->i_mount; - xfs_fileoff_t offset_fsb = imap->br_startoff; - xfs_filblks_t count_fsb = imap->br_blockcount; struct xfs_trans *tp; - int nimaps, error = 0; - bool found; xfs_filblks_t resaligned; - xfs_extlen_t resblks = 0; - - ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); - if (!ip->i_cowfp) { - ASSERT(!xfs_is_reflink_inode(ip)); - xfs_ifork_init_cow(ip); - } - - error = xfs_find_trim_cow_extent(ip, imap, cmap, shared, &found); - if (error || !*shared) - return error; - if (found) - goto convert; + xfs_extlen_t resblks; + 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); xfs_iunlock(ip, *lockmode); - error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0, &tp); - *lockmode = XFS_ILOCK_EXCL; - xfs_ilock(ip, *lockmode); + *lockmode = 0; + error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, resblks, 0, + false, &tp); if (error) return error; - error = xfs_qm_dqattach_locked(ip, false); - if (error) - goto out_trans_cancel; + *lockmode = XFS_ILOCK_EXCL; - /* - * Check for an overlapping extent again now that we dropped the ilock. - */ error = xfs_find_trim_cow_extent(ip, imap, cmap, shared, &found); if (error || !*shared) goto out_trans_cancel; + if (found) { xfs_trans_cancel(tp); goto convert; } - error = xfs_trans_reserve_quota_nblks(tp, ip, resblks, 0, - XFS_QMOPT_RES_REGBLKS); - if (error) - goto out_trans_cancel; - - xfs_trans_ijoin(tp, ip, 0); + ASSERT(cmap->br_startoff > imap->br_startoff); /* Allocate the entire reservation as unwritten blocks. */ nimaps = 1; @@ -411,7 +424,7 @@ xfs_reflink_allocate_cow( XFS_BMAPI_COWFORK | XFS_BMAPI_PREALLOC, 0, cmap, &nimaps); if (error) - goto out_unreserve; + goto out_trans_cancel; xfs_inode_set_cowblocks_tag(ip); error = xfs_trans_commit(tp); @@ -424,26 +437,135 @@ xfs_reflink_allocate_cow( */ if (nimaps == 0) return -ENOSPC; + convert: - xfs_trim_extent(cmap, offset_fsb, count_fsb); - /* - * COW fork extents are supposed to remain unwritten until we're ready - * to initiate a disk write. For direct I/O we are going to write the - * data and need the conversion, but for buffered writes we're done. - */ - if (!convert_now || cmap->br_state == XFS_EXT_NORM) - return 0; - trace_xfs_reflink_convert_cow(ip, cmap); - return xfs_reflink_convert_cow_locked(ip, offset_fsb, count_fsb); + return xfs_reflink_convert_unwritten(ip, imap, cmap, convert_now); + +out_trans_cancel: + xfs_trans_cancel(tp); + return error; +} + +static int +xfs_reflink_fill_delalloc( + struct xfs_inode *ip, + struct xfs_bmbt_irec *imap, + struct xfs_bmbt_irec *cmap, + bool *shared, + uint *lockmode, + bool convert_now) +{ + struct xfs_mount *mp = ip->i_mount; + struct xfs_trans *tp; + int nimaps; + int error; + bool found; + + do { + xfs_iunlock(ip, *lockmode); + *lockmode = 0; + + error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, 0, 0, + false, &tp); + if (error) + return error; + + *lockmode = XFS_ILOCK_EXCL; + + error = xfs_find_trim_cow_extent(ip, imap, cmap, shared, + &found); + if (error || !*shared) + goto out_trans_cancel; + + if (found) { + xfs_trans_cancel(tp); + break; + } + + ASSERT(isnullstartblock(cmap->br_startblock) || + cmap->br_startblock == DELAYSTARTBLOCK); + + /* + * Replace delalloc reservation with an unwritten extent. + */ + nimaps = 1; + error = xfs_bmapi_write(tp, ip, cmap->br_startoff, + cmap->br_blockcount, + XFS_BMAPI_COWFORK | XFS_BMAPI_PREALLOC, 0, + cmap, &nimaps); + if (error) + goto out_trans_cancel; + + xfs_inode_set_cowblocks_tag(ip); + 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); -out_unreserve: - xfs_trans_unreserve_quota_nblks(tp, ip, (long)resblks, 0, - XFS_QMOPT_RES_REGBLKS); out_trans_cancel: xfs_trans_cancel(tp); return error; } +/* Allocate all CoW reservations covering a range of blocks in a file. */ +int +xfs_reflink_allocate_cow( + struct xfs_inode *ip, + struct xfs_bmbt_irec *imap, + struct xfs_bmbt_irec *cmap, + bool *shared, + uint *lockmode, + bool convert_now) +{ + int error; + bool found; + + ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); + if (!ip->i_cowfp) { + ASSERT(!xfs_is_reflink_inode(ip)); + xfs_ifork_init_cow(ip); + } + + error = xfs_find_trim_cow_extent(ip, imap, cmap, shared, &found); + if (error || !*shared) + return error; + + /* CoW fork has a real extent */ + if (found) + return xfs_reflink_convert_unwritten(ip, imap, cmap, + convert_now); + + /* + * CoW fork does not have an extent and data extent is shared. + * Allocate a real extent in the CoW fork. + */ + if (cmap->br_startoff > imap->br_startoff) + return xfs_reflink_fill_cow_hole(ip, imap, cmap, shared, + lockmode, convert_now); + + /* + * CoW fork has a delalloc reservation. Replace it with a real extent. + * There may or may not be a data fork mapping. + */ + if (isnullstartblock(cmap->br_startblock) || + cmap->br_startblock == DELAYSTARTBLOCK) + return xfs_reflink_fill_delalloc(ip, imap, cmap, shared, + lockmode, convert_now); + + /* Shouldn't get here. */ + ASSERT(0); + return -EFSCORRUPTED; +} + /* * Cancel CoW reservations for some block range of an inode. * @@ -461,7 +583,7 @@ xfs_reflink_cancel_cow_blocks( xfs_fileoff_t end_fsb, bool cancel_real) { - struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK); + struct xfs_ifork *ifp = xfs_ifork_ptr(ip, XFS_COW_FORK); struct xfs_bmbt_irec got, del; struct xfs_iext_cursor icur; int error = 0; @@ -496,7 +618,7 @@ xfs_reflink_cancel_cow_blocks( xfs_refcount_free_cow_extent(*tpp, del.br_startblock, del.br_blockcount); - xfs_bmap_add_free(*tpp, del.br_startblock, + xfs_free_extent_later(*tpp, del.br_startblock, del.br_blockcount, NULL); /* Roll the transaction */ @@ -508,9 +630,8 @@ xfs_reflink_cancel_cow_blocks( xfs_bmap_del_extent_cow(ip, &icur, &got, &del); /* Remove the quota reservation */ - error = xfs_trans_reserve_quota_nblks(NULL, ip, - -(long)del.br_blockcount, 0, - XFS_QMOPT_RES_REGBLKS); + error = xfs_quota_unreserve_blkres(ip, + del.br_blockcount); if (error) break; } else { @@ -596,21 +717,21 @@ out: STATIC int xfs_reflink_end_cow_extent( struct xfs_inode *ip, - xfs_fileoff_t offset_fsb, - xfs_fileoff_t *end_fsb) + xfs_fileoff_t *offset_fsb, + xfs_fileoff_t end_fsb) { - struct xfs_bmbt_irec got, del; struct xfs_iext_cursor icur; + struct xfs_bmbt_irec got, del, data; struct xfs_mount *mp = ip->i_mount; struct xfs_trans *tp; - struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK); - xfs_filblks_t rlen; + struct xfs_ifork *ifp = xfs_ifork_ptr(ip, XFS_COW_FORK); unsigned int resblks; + int nmaps; int error; /* No COW extents? That's easy! */ if (ifp->if_bytes == 0) { - *end_fsb = offset_fsb; + *offset_fsb = end_fsb; return 0; } @@ -628,47 +749,79 @@ 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 * case we are done. */ - if (!xfs_iext_lookup_extent_before(ip, ifp, end_fsb, &icur, &got) || - got.br_startoff + got.br_blockcount <= offset_fsb) { - *end_fsb = offset_fsb; + if (!xfs_iext_lookup_extent(ip, ifp, *offset_fsb, &icur, &got) || + got.br_startoff >= end_fsb) { + *offset_fsb = end_fsb; goto out_cancel; } /* - * Structure copy @got into @del, then trim @del to the range that we - * were asked to remap. We preserve @got for the eventual CoW fork - * deletion; from now on @del represents the mapping that we're - * actually remapping. - */ - del = got; - xfs_trim_extent(&del, offset_fsb, *end_fsb - offset_fsb); - - ASSERT(del.br_blockcount > 0); - - /* * Only remap real extents that contain data. With AIO, speculative * preallocations can leak into the range we are called upon, and we - * need to skip them. + * need to skip them. Preserve @got for the eventual CoW fork + * deletion; from now on @del represents the mapping that we're + * actually remapping. */ - if (!xfs_bmap_is_real_extent(&got)) { - *end_fsb = del.br_startoff; - goto out_cancel; + while (!xfs_bmap_is_written_extent(&got)) { + if (!xfs_iext_next_extent(ifp, &icur, &got) || + got.br_startoff >= end_fsb) { + *offset_fsb = end_fsb; + goto out_cancel; + } } + del = got; - /* Unmap the old blocks in the data fork. */ - rlen = del.br_blockcount; - error = __xfs_bunmapi(tp, ip, del.br_startoff, &rlen, 0, 1); + /* Grab the corresponding mapping in the data fork. */ + nmaps = 1; + error = xfs_bmapi_read(ip, del.br_startoff, del.br_blockcount, &data, + &nmaps, 0); if (error) goto out_cancel; - /* Trim the extent to whatever got unmapped. */ - xfs_trim_extent(&del, del.br_startoff + rlen, del.br_blockcount - rlen); - trace_xfs_reflink_cow_remap(ip, &del); + /* We can only remap the smaller of the two extent sizes. */ + data.br_blockcount = min(data.br_blockcount, del.br_blockcount); + del.br_blockcount = data.br_blockcount; + + trace_xfs_reflink_cow_remap_from(ip, &del); + trace_xfs_reflink_cow_remap_to(ip, &data); + + if (xfs_bmap_is_real_extent(&data)) { + /* + * 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); + } else if (data.br_startblock == DELAYSTARTBLOCK) { + int done; + + /* + * If the extent we're remapping is a delalloc reservation, + * we can use the regular bunmapi function to release the + * incore state. Dropping the delalloc reservation takes care + * of the quota reservation for us. + */ + error = xfs_bunmapi(NULL, ip, data.br_startoff, + data.br_blockcount, 0, 1, &done); + if (error) + goto out_cancel; + ASSERT(done); + } /* Free the CoW orphan record. */ xfs_refcount_free_cow_extent(tp, del.br_startblock, del.br_blockcount); @@ -689,7 +842,7 @@ xfs_reflink_end_cow_extent( return error; /* Update the caller about how much progress we made. */ - *end_fsb = del.br_startoff; + *offset_fsb = del.br_startoff + del.br_blockcount; return 0; out_cancel: @@ -717,11 +870,11 @@ xfs_reflink_end_cow( end_fsb = XFS_B_TO_FSB(ip->i_mount, offset + count); /* - * Walk backwards until we're out of the I/O range. The loop function + * Walk forwards until we've remapped the I/O range. The loop function * repeatedly cycles the ILOCK to allocate one transaction per remapped * extent. * - * If we're being called by writeback then the the pages will still + * If we're being called by writeback then the pages will still * have PageWriteback set, which prevents races with reflink remapping * and truncate. Reflink remapping prevents races with writeback by * taking the iolock and mmaplock before flushing the pages and @@ -749,7 +902,7 @@ xfs_reflink_end_cow( * blocks will be remapped. */ while (end_fsb > offset_fsb && !error) - error = xfs_reflink_end_cow_extent(ip, offset_fsb, &end_fsb); + error = xfs_reflink_end_cow_extent(ip, &offset_fsb, end_fsb); if (error) trace_xfs_reflink_end_cow_error(ip, error, _RET_IP_); @@ -757,22 +910,28 @@ xfs_reflink_end_cow( } /* - * Free leftover CoW reservations that didn't get cleaned out. + * Free all CoW staging blocks that are still referenced by the ondisk refcount + * metadata. The ondisk metadata does not track which inode created the + * staging extent, so callers must ensure that there are no cached inodes with + * live CoW staging extents. */ int xfs_reflink_recover_cow( struct xfs_mount *mp) { + struct xfs_perag *pag; xfs_agnumber_t agno; int error = 0; - if (!xfs_sb_version_hasreflink(&mp->m_sb)) + if (!xfs_has_reflink(mp)) return 0; - for (agno = 0; agno < mp->m_sb.sb_agcount; agno++) { - error = xfs_refcount_recover_cow_leftovers(mp, agno); - if (error) + for_each_perag(mp, agno, pag) { + error = xfs_refcount_recover_cow_leftovers(mp, pag); + if (error) { + xfs_perag_put(pag); break; + } } return error; @@ -882,7 +1041,7 @@ xfs_reflink_set_inode_flag( if (!xfs_is_reflink_inode(src)) { trace_xfs_reflink_set_inode_flag(src); xfs_trans_ijoin(tp, src, XFS_ILOCK_EXCL); - src->i_d.di_flags2 |= XFS_DIFLAG2_REFLINK; + src->i_diflags2 |= XFS_DIFLAG2_REFLINK; xfs_trans_log_inode(tp, src, XFS_ILOG_CORE); xfs_ifork_init_cow(src); } else @@ -894,7 +1053,7 @@ xfs_reflink_set_inode_flag( if (!xfs_is_reflink_inode(dest)) { trace_xfs_reflink_set_inode_flag(dest); xfs_trans_ijoin(tp, dest, XFS_ILOCK_EXCL); - dest->i_d.di_flags2 |= XFS_DIFLAG2_REFLINK; + dest->i_diflags2 |= XFS_DIFLAG2_REFLINK; xfs_trans_log_inode(tp, dest, XFS_ILOG_CORE); xfs_ifork_init_cow(dest); } else @@ -938,12 +1097,12 @@ xfs_reflink_update_dest( if (newlen > i_size_read(VFS_I(dest))) { trace_xfs_reflink_update_inode_size(dest, newlen); i_size_write(VFS_I(dest), newlen); - dest->i_d.di_size = newlen; + dest->i_disk_size = newlen; } if (cowextsize) { - dest->i_d.di_cowextsize = cowextsize; - dest->i_d.di_flags2 |= XFS_DIFLAG2_COWEXTSIZE; + dest->i_cowextsize = cowextsize; + dest->i_diflags2 |= XFS_DIFLAG2_COWEXTSIZE; } xfs_trans_log_inode(tp, dest, XFS_ILOG_CORE); @@ -972,7 +1131,7 @@ xfs_reflink_ag_has_free_space( struct xfs_perag *pag; int error = 0; - if (!xfs_sb_version_hasrmapbt(&mp->m_sb)) + if (!xfs_has_rmapbt(mp)) return 0; pag = xfs_perag_get(mp, agno); @@ -984,127 +1143,208 @@ xfs_reflink_ag_has_free_space( } /* - * Unmap a range of blocks from a file, then map other blocks into the hole. - * The range to unmap is (destoff : destoff + srcioff + irec->br_blockcount). - * The extent irec is mapped into dest at irec->br_startoff. + * Remap the given extent into the file. The dmap blockcount will be set to + * the number of blocks that were actually remapped. */ STATIC int xfs_reflink_remap_extent( struct xfs_inode *ip, - struct xfs_bmbt_irec *irec, - xfs_fileoff_t destoff, + struct xfs_bmbt_irec *dmap, xfs_off_t new_isize) { + struct xfs_bmbt_irec smap; struct xfs_mount *mp = ip->i_mount; - bool real_extent = xfs_bmap_is_real_extent(irec); struct xfs_trans *tp; - unsigned int resblks; - struct xfs_bmbt_irec uirec; - xfs_filblks_t rlen; - xfs_filblks_t unmap_len; xfs_off_t newlen; + int64_t qdelta = 0; + unsigned int resblks; + bool quota_reserved = true; + bool smap_real; + bool dmap_written = xfs_bmap_is_written_extent(dmap); + int iext_delta = 0; + int nimaps; int error; - unmap_len = irec->br_startoff + irec->br_blockcount - destoff; - trace_xfs_reflink_punch_range(ip, destoff, unmap_len); - - /* No reflinking if we're low on space */ - if (real_extent) { - error = xfs_reflink_ag_has_free_space(mp, - XFS_FSB_TO_AGNO(mp, irec->br_startblock)); - if (error) - goto out; + /* + * Start a rolling transaction to switch the mappings. + * + * Adding a written extent to the extent map can cause a bmbt split, + * and removing a mapped extent from the extent can cause a bmbt split. + * The two operations cannot both cause a split since they operate on + * the same index in the bmap btree, so we only need a reservation for + * one bmbt split if either thing is happening. However, we haven't + * locked the inode yet, so we reserve assuming this is the case. + * + * The first allocation call tries to reserve enough space to handle + * mapping dmap into a sparse part of the file plus the bmbt split. We + * haven't locked the inode or read the existing mapping yet, so we do + * not know for sure that we need the space. This should succeed most + * of the time. + * + * If the first attempt fails, try again but reserving only enough + * space to handle a bmbt split. This is the hard minimum requirement, + * and we revisit quota reservations later when we know more about what + * we're remapping. + */ + resblks = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK); + error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, + resblks + dmap->br_blockcount, 0, false, &tp); + if (error == -EDQUOT || error == -ENOSPC) { + quota_reserved = false; + error = xfs_trans_alloc_inode(ip, &M_RES(mp)->tr_write, + resblks, 0, false, &tp); } - - /* Start a rolling transaction to switch the mappings */ - resblks = XFS_EXTENTADD_SPACE_RES(ip->i_mount, XFS_DATA_FORK); - error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0, 0, &tp); if (error) goto out; - xfs_ilock(ip, XFS_ILOCK_EXCL); - xfs_trans_ijoin(tp, ip, 0); + /* + * Read what's currently mapped in the destination file into smap. + * If smap isn't a hole, we will have to remove it before we can add + * dmap to the destination file. + */ + nimaps = 1; + error = xfs_bmapi_read(ip, dmap->br_startoff, dmap->br_blockcount, + &smap, &nimaps, 0); + if (error) + goto out_cancel; + ASSERT(nimaps == 1 && smap.br_startoff == dmap->br_startoff); + smap_real = xfs_bmap_is_real_extent(&smap); - /* If we're not just clearing space, then do we have enough quota? */ - if (real_extent) { - error = xfs_trans_reserve_quota_nblks(tp, ip, - irec->br_blockcount, 0, XFS_QMOPT_RES_REGBLKS); - if (error) - goto out_cancel; + /* + * We can only remap as many blocks as the smaller of the two extent + * maps, because we can only remap one extent at a time. + */ + dmap->br_blockcount = min(dmap->br_blockcount, smap.br_blockcount); + ASSERT(dmap->br_blockcount == smap.br_blockcount); + + trace_xfs_reflink_remap_extent_dest(ip, &smap); + + /* + * Two extents mapped to the same physical block must not have + * different states; that's filesystem corruption. Move on to the next + * 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) + error = -EFSCORRUPTED; + goto out_cancel; } - trace_xfs_reflink_remap(ip, irec->br_startoff, - irec->br_blockcount, irec->br_startblock); + /* If both extents are unwritten, leave them alone. */ + if (dmap->br_state == XFS_EXT_UNWRITTEN && + smap.br_state == XFS_EXT_UNWRITTEN) + goto out_cancel; - /* Unmap the old blocks in the data fork. */ - rlen = unmap_len; - while (rlen) { - ASSERT(tp->t_firstblock == NULLFSBLOCK); - error = __xfs_bunmapi(tp, ip, destoff, &rlen, 0, 1); + /* 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)); if (error) goto out_cancel; + } - /* - * Trim the extent to whatever got unmapped. - * Remember, bunmapi works backwards. - */ - uirec.br_startblock = irec->br_startblock + rlen; - uirec.br_startoff = irec->br_startoff + rlen; - uirec.br_blockcount = unmap_len - rlen; - unmap_len = rlen; - - /* If this isn't a real mapping, we're done. */ - if (!real_extent || uirec.br_blockcount == 0) - goto next_extent; + /* + * Increase quota reservation if we think the quota block counter for + * this file could increase. + * + * If we are mapping a written extent into the file, we need to have + * enough quota block count reservation to handle the blocks in that + * extent. We log only the delta to the quota block counts, so if the + * extent we're unmapping also has blocks allocated to it, we don't + * need a quota reservation for the extent itself. + * + * Note that if we're replacing a delalloc reservation with a written + * extent, we have to take the full quota reservation because removing + * the delalloc reservation gives the block count back to the quota + * count. This is suboptimal, but the VFS flushed the dest range + * before we started. That should have removed all the delalloc + * reservations, but we code defensively. + * + * xfs_trans_alloc_inode above already tried to grab an even larger + * quota reservation, and kicked off a blockgc scan if it couldn't. + * If we can't get a potentially smaller quota reservation now, we're + * done. + */ + if (!quota_reserved && !smap_real && dmap_written) { + error = xfs_trans_reserve_quota_nblks(tp, ip, + dmap->br_blockcount, 0, false); + if (error) + goto out_cancel; + } - trace_xfs_reflink_remap(ip, uirec.br_startoff, - uirec.br_blockcount, uirec.br_startblock); + if (smap_real) + ++iext_delta; - /* Update the refcount tree */ - xfs_refcount_increase_extent(tp, &uirec); + if (dmap_written) + ++iext_delta; - /* Map the new blocks into the data fork. */ - xfs_bmap_map_extent(tp, ip, &uirec); + error = xfs_iext_count_may_overflow(ip, XFS_DATA_FORK, iext_delta); + if (error == -EFBIG) + error = xfs_iext_count_upgrade(tp, ip, iext_delta); + if (error) + goto out_cancel; - /* Update quota accounting. */ - xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, - uirec.br_blockcount); - - /* Update dest isize if needed. */ - newlen = XFS_FSB_TO_B(mp, - uirec.br_startoff + uirec.br_blockcount); - newlen = min_t(xfs_off_t, newlen, new_isize); - if (newlen > i_size_read(VFS_I(ip))) { - trace_xfs_reflink_update_inode_size(ip, newlen); - i_size_write(VFS_I(ip), newlen); - ip->i_d.di_size = newlen; - xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); - } + if (smap_real) { + /* + * 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); + qdelta -= smap.br_blockcount; + } else if (smap.br_startblock == DELAYSTARTBLOCK) { + int done; -next_extent: - /* Process all the deferred stuff. */ - error = xfs_defer_finish(&tp); + /* + * If the extent we're unmapping is a delalloc reservation, + * we can use the regular bunmapi function to release the + * incore state. Dropping the delalloc reservation takes care + * of the quota reservation for us. + */ + error = xfs_bunmapi(NULL, ip, smap.br_startoff, + smap.br_blockcount, 0, 1, &done); if (error) goto out_cancel; + ASSERT(done); + } + + /* + * If the extent we're sharing is backed by written storage, increase + * its refcount and map it into the file. + */ + if (dmap_written) { + xfs_refcount_increase_extent(tp, dmap); + xfs_bmap_map_extent(tp, ip, dmap); + qdelta += dmap->br_blockcount; + } + + xfs_trans_mod_dquot_byino(tp, ip, XFS_TRANS_DQ_BCOUNT, qdelta); + + /* Update dest isize if needed. */ + newlen = XFS_FSB_TO_B(mp, dmap->br_startoff + dmap->br_blockcount); + newlen = min_t(xfs_off_t, newlen, new_isize); + if (newlen > i_size_read(VFS_I(ip))) { + trace_xfs_reflink_update_inode_size(ip, newlen); + i_size_write(VFS_I(ip), newlen); + ip->i_disk_size = newlen; + xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); } + /* Commit everything and unlock. */ error = xfs_trans_commit(tp); - xfs_iunlock(ip, XFS_ILOCK_EXCL); - if (error) - goto out; - return 0; + goto out_unlock; out_cancel: xfs_trans_cancel(tp); +out_unlock: xfs_iunlock(ip, XFS_ILOCK_EXCL); out: - trace_xfs_reflink_remap_extent_error(ip, error, _RET_IP_); + if (error) + trace_xfs_reflink_remap_extent_error(ip, error, _RET_IP_); return error; } -/* - * Iteratively remap one file's extents (and holes) to another's. - */ +/* Remap a range of one file to the other. */ int xfs_reflink_remap_blocks( struct xfs_inode *src, @@ -1115,25 +1355,22 @@ xfs_reflink_remap_blocks( loff_t *remapped) { struct xfs_bmbt_irec imap; - xfs_fileoff_t srcoff; - xfs_fileoff_t destoff; + struct xfs_mount *mp = src->i_mount; + xfs_fileoff_t srcoff = XFS_B_TO_FSBT(mp, pos_in); + xfs_fileoff_t destoff = XFS_B_TO_FSBT(mp, pos_out); xfs_filblks_t len; - xfs_filblks_t range_len; xfs_filblks_t remapped_len = 0; xfs_off_t new_isize = pos_out + remap_len; int nimaps; int error = 0; - destoff = XFS_B_TO_FSBT(src->i_mount, pos_out); - srcoff = XFS_B_TO_FSBT(src->i_mount, pos_in); - len = XFS_B_TO_FSB(src->i_mount, remap_len); + len = min_t(xfs_filblks_t, XFS_B_TO_FSB(mp, remap_len), + XFS_MAX_FILEOFF); - /* drange = (destoff, destoff + len); srange = (srcoff, srcoff + len) */ - while (len) { - uint lock_mode; + trace_xfs_reflink_remap_blocks(src, srcoff, len, dest, destoff); - trace_xfs_reflink_remap_blocks_loop(src, srcoff, len, - dest, destoff); + while (len > 0) { + unsigned int lock_mode; /* Read extent from the source file */ nimaps = 1; @@ -1142,18 +1379,25 @@ xfs_reflink_remap_blocks( xfs_iunlock(src, lock_mode); if (error) break; - ASSERT(nimaps == 1); - - trace_xfs_reflink_remap_imap(src, srcoff, len, XFS_DATA_FORK, - &imap); + /* + * The caller supposedly flushed all dirty pages in the source + * file range, which means that writeback should have allocated + * or deleted all delalloc reservations in that range. If we + * find one, that's a good sign that something is seriously + * wrong here. + */ + ASSERT(nimaps == 1 && imap.br_startoff == srcoff); + if (imap.br_startblock == DELAYSTARTBLOCK) { + ASSERT(imap.br_startblock != DELAYSTARTBLOCK); + error = -EFSCORRUPTED; + break; + } - /* Translate imap into the destination file. */ - range_len = imap.br_startoff + imap.br_blockcount - srcoff; - imap.br_startoff += destoff - srcoff; + trace_xfs_reflink_remap_extent_src(src, &imap); - /* Clear dest from destoff to the end of imap and map it in. */ - error = xfs_reflink_remap_extent(dest, &imap, destoff, - new_isize); + /* Remap into the destination file at the given offset. */ + imap.br_startoff = destoff; + error = xfs_reflink_remap_extent(dest, &imap, new_isize); if (error) break; @@ -1163,10 +1407,10 @@ xfs_reflink_remap_blocks( } /* Advance drange/srange */ - srcoff += range_len; - destoff += range_len; - len -= range_len; - remapped_len += range_len; + srcoff += imap.br_blockcount; + destoff += imap.br_blockcount; + len -= imap.br_blockcount; + remapped_len += imap.br_blockcount; } if (error) @@ -1177,81 +1421,6 @@ xfs_reflink_remap_blocks( } /* - * Grab the exclusive iolock for a data copy from src to dest, making sure to - * abide vfs locking order (lowest pointer value goes first) and breaking the - * layout leases before proceeding. The loop is needed because we cannot call - * the blocking break_layout() with the iolocks held, and therefore have to - * back out both locks. - */ -static int -xfs_iolock_two_inodes_and_break_layout( - struct inode *src, - struct inode *dest) -{ - int error; - - if (src > dest) - swap(src, dest); - -retry: - /* Wait to break both inodes' layouts before we start locking. */ - error = break_layout(src, true); - if (error) - return error; - if (src != dest) { - error = break_layout(dest, true); - if (error) - return error; - } - - /* Lock one inode and make sure nobody got in and leased it. */ - inode_lock(src); - error = break_layout(src, false); - if (error) { - inode_unlock(src); - if (error == -EWOULDBLOCK) - goto retry; - return error; - } - - if (src == dest) - return 0; - - /* Lock the other inode and make sure nobody got in and leased it. */ - inode_lock_nested(dest, I_MUTEX_NONDIR2); - error = break_layout(dest, false); - if (error) { - inode_unlock(src); - inode_unlock(dest); - if (error == -EWOULDBLOCK) - goto retry; - return error; - } - - return 0; -} - -/* Unlock both inodes after they've been prepped for a range clone. */ -void -xfs_reflink_remap_unlock( - struct file *file_in, - struct file *file_out) -{ - struct inode *inode_in = file_inode(file_in); - struct xfs_inode *src = XFS_I(inode_in); - struct inode *inode_out = file_inode(file_out); - struct xfs_inode *dest = XFS_I(inode_out); - bool same_inode = (inode_in == inode_out); - - xfs_iunlock(dest, XFS_MMAPLOCK_EXCL); - if (!same_inode) - xfs_iunlock(src, XFS_MMAPLOCK_EXCL); - inode_unlock(inode_out); - if (!same_inode) - inode_unlock(inode_in); -} - -/* * If we're reflinking to a point past the destination file's EOF, we must * zero any speculative post-EOF preallocations that sit between the old EOF * and the destination file offset. @@ -1267,8 +1436,7 @@ xfs_reflink_zero_posteof( return 0; trace_xfs_zero_eof(ip, isize, pos - isize); - return iomap_zero_range(VFS_I(ip), isize, pos - isize, NULL, - &xfs_buffered_write_iomap_ops); + return xfs_zero_range(ip, isize, pos - isize, NULL); } /* @@ -1313,18 +1481,12 @@ xfs_reflink_remap_prep( struct xfs_inode *src = XFS_I(inode_in); struct inode *inode_out = file_inode(file_out); struct xfs_inode *dest = XFS_I(inode_out); - bool same_inode = (inode_in == inode_out); - ssize_t ret; + int ret; /* Lock both files against IO */ - ret = xfs_iolock_two_inodes_and_break_layout(inode_in, inode_out); + ret = xfs_ilock2_io_mmap(src, dest); if (ret) return ret; - if (same_inode) - xfs_ilock(src, XFS_MMAPLOCK_EXCL); - else - xfs_lock_two_inodes(src, XFS_MMAPLOCK_EXCL, dest, - XFS_MMAPLOCK_EXCL); /* Check file eligibility and prepare for block sharing. */ ret = -EINVAL; @@ -1332,13 +1494,17 @@ xfs_reflink_remap_prep( if (XFS_IS_REALTIME_INODE(src) || XFS_IS_REALTIME_INODE(dest)) goto out_unlock; - /* Don't share DAX file data for now. */ - if (IS_DAX(inode_in) || IS_DAX(inode_out)) + /* Don't share DAX file data with non-DAX file. */ + if (IS_DAX(inode_in) != IS_DAX(inode_out)) goto out_unlock; - ret = generic_remap_file_range_prep(file_in, pos_in, file_out, pos_out, - len, remap_flags); - if (ret < 0 || *len == 0) + if (!IS_DAX(inode_in)) + ret = generic_remap_file_range_prep(file_in, pos_in, file_out, + pos_out, len, remap_flags); + else + ret = dax_remap_file_range_prep(file_in, pos_in, file_out, + pos_out, len, remap_flags, &xfs_read_iomap_ops); + if (ret || *len == 0) goto out_unlock; /* Attach dquots to dest inode before changing block map */ @@ -1373,9 +1539,9 @@ xfs_reflink_remap_prep( if (ret) goto out_unlock; - return 1; + return 0; out_unlock: - xfs_reflink_remap_unlock(file_in, file_out); + xfs_iunlock2_io_mmap(src, dest); return ret; } @@ -1389,36 +1555,37 @@ xfs_reflink_inode_has_shared_extents( struct xfs_bmbt_irec got; struct xfs_mount *mp = ip->i_mount; struct xfs_ifork *ifp; - xfs_agnumber_t agno; - xfs_agblock_t agbno; - xfs_extlen_t aglen; - xfs_agblock_t rbno; - xfs_extlen_t rlen; struct xfs_iext_cursor icur; bool found; int error; - ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK); - if (!(ifp->if_flags & XFS_IFEXTENTS)) { - error = xfs_iread_extents(tp, ip, XFS_DATA_FORK); - if (error) - return error; - } + ifp = xfs_ifork_ptr(ip, XFS_DATA_FORK); + error = xfs_iread_extents(tp, ip, XFS_DATA_FORK); + if (error) + return error; *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; + if (isnullstartblock(got.br_startblock) || got.br_state != XFS_EXT_NORM) goto next; - agno = XFS_FSB_TO_AGNO(mp, got.br_startblock); + + 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(mp, tp, agno, agbno, aglen, + error = xfs_reflink_find_shared(pag, tp, agbno, aglen, &rbno, &rlen, false); + xfs_perag_put(pag); if (error) return error; + /* Is there still a shared block here? */ if (rbno != NULLAGBLOCK) { *has_shared = true; @@ -1462,7 +1629,7 @@ xfs_reflink_clear_inode_flag( /* Clear the inode flag. */ trace_xfs_reflink_unset_inode_flag(ip); - ip->i_d.di_flags2 &= ~XFS_DIFLAG2_REFLINK; + ip->i_diflags2 &= ~XFS_DIFLAG2_REFLINK; xfs_inode_clear_cowblocks_tag(ip); xfs_trans_log_inode(*tpp, ip, XFS_ILOG_CORE); @@ -1530,7 +1697,9 @@ xfs_reflink_unshare( &xfs_buffered_write_iomap_ops); if (error) goto out; - error = filemap_write_and_wait(inode->i_mapping); + + error = filemap_write_and_wait_range(inode->i_mapping, offset, + offset + len - 1); if (error) goto out; |