The maximum extent length depends on maximum block count that can be stored in a BMBT record. Hence this commit defines MAXEXTLEN based on BMBT_BLOCKCOUNT_BITLEN. While at it, the commit also renames MAXEXTLEN to XFS_MAX_EXTLEN. Suggested-by: Darrick J. Wong <djwong@xxxxxxxxxx> Signed-off-by: Chandan Babu R <chandan.babu@xxxxxxxxxx> --- fs/xfs/libxfs/xfs_bmap.c | 59 +++++++++++++++++----------------- fs/xfs/libxfs/xfs_format.h | 20 ++++++------ fs/xfs/libxfs/xfs_inode_buf.c | 4 +-- fs/xfs/libxfs/xfs_rtbitmap.c | 4 +-- fs/xfs/libxfs/xfs_swapext.c | 6 ++-- fs/xfs/libxfs/xfs_trans_resv.c | 10 +++--- fs/xfs/scrub/bmap.c | 2 +- fs/xfs/scrub/bmap_repair.c | 2 +- fs/xfs/scrub/repair.c | 2 +- fs/xfs/xfs_bmap_util.c | 14 ++++---- fs/xfs/xfs_iomap.c | 28 ++++++++-------- 11 files changed, 77 insertions(+), 74 deletions(-) diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c index a77cf8619ec0..fb10ea078361 100644 --- a/fs/xfs/libxfs/xfs_bmap.c +++ b/fs/xfs/libxfs/xfs_bmap.c @@ -548,7 +548,7 @@ __xfs_bmap_add_free( ASSERT(bno != NULLFSBLOCK); ASSERT(len > 0); - ASSERT(len <= MAXEXTLEN); + ASSERT(len <= XFS_MAX_EXTLEN); ASSERT(!isnullstartblock(bno)); agno = XFS_FSB_TO_AGNO(mp, bno); agbno = XFS_FSB_TO_AGBNO(mp, bno); @@ -1504,7 +1504,7 @@ xfs_bmap_add_extent_delay_real( LEFT.br_startoff + LEFT.br_blockcount == new->br_startoff && LEFT.br_startblock + LEFT.br_blockcount == new->br_startblock && LEFT.br_state == new->br_state && - LEFT.br_blockcount + new->br_blockcount <= MAXEXTLEN) + LEFT.br_blockcount + new->br_blockcount <= XFS_MAX_EXTLEN) state |= BMAP_LEFT_CONTIG; /* @@ -1522,13 +1522,13 @@ xfs_bmap_add_extent_delay_real( new_endoff == RIGHT.br_startoff && new->br_startblock + new->br_blockcount == RIGHT.br_startblock && new->br_state == RIGHT.br_state && - new->br_blockcount + RIGHT.br_blockcount <= MAXEXTLEN && + new->br_blockcount + RIGHT.br_blockcount <= XFS_MAX_EXTLEN && ((state & (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING)) != (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING) || LEFT.br_blockcount + new->br_blockcount + RIGHT.br_blockcount - <= MAXEXTLEN)) + <= XFS_MAX_EXTLEN)) state |= BMAP_RIGHT_CONTIG; error = 0; @@ -2067,7 +2067,7 @@ xfs_bmap_add_extent_unwritten_real( LEFT.br_startoff + LEFT.br_blockcount == new->br_startoff && LEFT.br_startblock + LEFT.br_blockcount == new->br_startblock && LEFT.br_state == new->br_state && - LEFT.br_blockcount + new->br_blockcount <= MAXEXTLEN) + LEFT.br_blockcount + new->br_blockcount <= XFS_MAX_EXTLEN) state |= BMAP_LEFT_CONTIG; /* @@ -2085,13 +2085,13 @@ xfs_bmap_add_extent_unwritten_real( new_endoff == RIGHT.br_startoff && new->br_startblock + new->br_blockcount == RIGHT.br_startblock && new->br_state == RIGHT.br_state && - new->br_blockcount + RIGHT.br_blockcount <= MAXEXTLEN && + new->br_blockcount + RIGHT.br_blockcount <= XFS_MAX_EXTLEN && ((state & (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING)) != (BMAP_LEFT_CONTIG | BMAP_LEFT_FILLING | BMAP_RIGHT_FILLING) || LEFT.br_blockcount + new->br_blockcount + RIGHT.br_blockcount - <= MAXEXTLEN)) + <= XFS_MAX_EXTLEN)) state |= BMAP_RIGHT_CONTIG; /* @@ -2600,15 +2600,15 @@ xfs_bmap_add_extent_hole_delay( */ if ((state & BMAP_LEFT_VALID) && (state & BMAP_LEFT_DELAY) && left.br_startoff + left.br_blockcount == new->br_startoff && - left.br_blockcount + new->br_blockcount <= MAXEXTLEN) + left.br_blockcount + new->br_blockcount <= XFS_MAX_EXTLEN) state |= BMAP_LEFT_CONTIG; if ((state & BMAP_RIGHT_VALID) && (state & BMAP_RIGHT_DELAY) && new->br_startoff + new->br_blockcount == right.br_startoff && - new->br_blockcount + right.br_blockcount <= MAXEXTLEN && + new->br_blockcount + right.br_blockcount <= XFS_MAX_EXTLEN && (!(state & BMAP_LEFT_CONTIG) || (left.br_blockcount + new->br_blockcount + - right.br_blockcount <= MAXEXTLEN))) + right.br_blockcount <= XFS_MAX_EXTLEN))) state |= BMAP_RIGHT_CONTIG; /* @@ -2751,17 +2751,17 @@ xfs_bmap_add_extent_hole_real( left.br_startoff + left.br_blockcount == new->br_startoff && left.br_startblock + left.br_blockcount == new->br_startblock && left.br_state == new->br_state && - left.br_blockcount + new->br_blockcount <= MAXEXTLEN) + left.br_blockcount + new->br_blockcount <= XFS_MAX_EXTLEN) state |= BMAP_LEFT_CONTIG; if ((state & BMAP_RIGHT_VALID) && !(state & BMAP_RIGHT_DELAY) && new->br_startoff + new->br_blockcount == right.br_startoff && new->br_startblock + new->br_blockcount == right.br_startblock && new->br_state == right.br_state && - new->br_blockcount + right.br_blockcount <= MAXEXTLEN && + new->br_blockcount + right.br_blockcount <= XFS_MAX_EXTLEN && (!(state & BMAP_LEFT_CONTIG) || left.br_blockcount + new->br_blockcount + - right.br_blockcount <= MAXEXTLEN)) + right.br_blockcount <= XFS_MAX_EXTLEN)) state |= BMAP_RIGHT_CONTIG; error = 0; @@ -3003,15 +3003,15 @@ xfs_bmap_extsize_align( /* * For large extent hint sizes, the aligned extent might be larger than - * MAXEXTLEN. In that case, reduce the size by an extsz so that it pulls - * the length back under MAXEXTLEN. The outer allocation loops handle - * short allocation just fine, so it is safe to do this. We only want to - * do it when we are forced to, though, because it means more allocation - * operations are required. + * XFS_MAX_EXTLEN. In that case, reduce the size by an extsz so that it + * pulls the length back under XFS_MAX_EXTLEN. The outer allocation + * loops handle short allocation just fine, so it is safe to do this. We + * only want to do it when we are forced to, though, because it means + * more allocation operations are required. */ - while (align_alen > MAXEXTLEN) + while (align_alen > XFS_MAX_EXTLEN) align_alen -= extsz; - ASSERT(align_alen <= MAXEXTLEN); + ASSERT(align_alen <= XFS_MAX_EXTLEN); /* * If the previous block overlaps with this proposed allocation @@ -3101,9 +3101,9 @@ xfs_bmap_extsize_align( return -EINVAL; } else { ASSERT(orig_off >= align_off); - /* see MAXEXTLEN handling above */ + /* see XFS_MAX_EXTLEN handling above */ ASSERT(orig_end <= align_off + align_alen || - align_alen + extsz > MAXEXTLEN); + align_alen + extsz > XFS_MAX_EXTLEN); } #ifdef DEBUG @@ -4070,7 +4070,7 @@ xfs_bmapi_reserve_delalloc( * Cap the alloc length. Keep track of prealloc so we know whether to * tag the inode before we return. */ - alen = XFS_FILBLKS_MIN(len + prealloc, MAXEXTLEN); + alen = XFS_FILBLKS_MIN(len + prealloc, XFS_MAX_EXTLEN); if (!eof) alen = XFS_FILBLKS_MIN(alen, got->br_startoff - aoff); if (prealloc && alen >= len) @@ -4203,7 +4203,7 @@ xfs_bmapi_allocate( if (!xfs_iext_peek_prev_extent(ifp, &bma->icur, &bma->prev)) bma->prev.br_startoff = NULLFILEOFF; } else { - bma->length = XFS_FILBLKS_MIN(bma->length, MAXEXTLEN); + bma->length = XFS_FILBLKS_MIN(bma->length, XFS_MAX_EXTLEN); if (!bma->eof) bma->length = XFS_FILBLKS_MIN(bma->length, bma->got.br_startoff - bma->offset); @@ -4524,8 +4524,8 @@ xfs_bmapi_write( * xfs_extlen_t and therefore 32 bits. Hence we have to * check for 32-bit overflows and handle them here. */ - if (len > (xfs_filblks_t)MAXEXTLEN) - bma.length = MAXEXTLEN; + if (len > (xfs_filblks_t)XFS_MAX_EXTLEN) + bma.length = XFS_MAX_EXTLEN; else bma.length = len; @@ -4660,7 +4660,8 @@ xfs_bmapi_convert_delalloc( bma.ip = ip; bma.wasdel = true; bma.offset = bma.got.br_startoff; - bma.length = max_t(xfs_filblks_t, bma.got.br_blockcount, MAXEXTLEN); + bma.length = max_t(xfs_filblks_t, bma.got.br_blockcount, + XFS_MAX_EXTLEN); bma.minleft = xfs_bmapi_minleft(tp, ip, whichfork); /* @@ -4743,7 +4744,7 @@ xfs_bmapi_remap( ifp = XFS_IFORK_PTR(ip, whichfork); ASSERT(len > 0); - ASSERT(len <= (xfs_filblks_t)MAXEXTLEN); + ASSERT(len <= (xfs_filblks_t)XFS_MAX_EXTLEN); ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); ASSERT(!(flags & ~(XFS_BMAPI_ATTRFORK | XFS_BMAPI_PREALLOC | XFS_BMAPI_NORMAP))); @@ -5716,7 +5717,7 @@ xfs_bmse_can_merge( if ((left->br_startoff + left->br_blockcount != startoff) || (left->br_startblock + left->br_blockcount != got->br_startblock) || (left->br_state != got->br_state) || - (left->br_blockcount + got->br_blockcount > MAXEXTLEN)) + (left->br_blockcount + got->br_blockcount > XFS_MAX_EXTLEN)) return false; return true; diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h index 7d08bb0fe510..e0fb19761669 100644 --- a/fs/xfs/libxfs/xfs_format.h +++ b/fs/xfs/libxfs/xfs_format.h @@ -885,16 +885,6 @@ enum xfs_dinode_fmt { { XFS_DINODE_FMT_BTREE, "btree" }, \ { XFS_DINODE_FMT_UUID, "uuid" } -/* - * Max values for extlen and disk inode's extent counters. - */ -#define MAXEXTLEN ((xfs_extlen_t)0x1fffff) /* 21 bits */ -#define XFS_IFORK_EXTCNT_MAXU48 ((xfs_extnum_t)0xffffffffffff) /* Unsigned 48-bits */ -#define XFS_IFORK_EXTCNT_MAXU32 ((xfs_aextnum_t)0xffffffff) /* Unsigned 32-bits */ -#define XFS_IFORK_EXTCNT_MAXS32 ((xfs_extnum_t)0x7fffffff) /* Signed 32-bits */ -#define XFS_IFORK_EXTCNT_MAXS16 ((xfs_aextnum_t)0x7fff) /* Signed 16-bits */ - - /* * Inode minimum and maximum sizes. */ @@ -1701,6 +1691,16 @@ typedef struct xfs_bmbt_rec { typedef uint64_t xfs_bmbt_rec_base_t; /* use this for casts */ typedef xfs_bmbt_rec_t xfs_bmdr_rec_t; +/* + * Max values for extlen and disk inode's extent counters. + */ +#define XFS_MAX_EXTLEN ((xfs_extlen_t)(1 << BMBT_BLOCKCOUNT_BITLEN) - 1) +#define XFS_IFORK_EXTCNT_MAXU48 ((xfs_extnum_t)0xffffffffffff) /* Unsigned 48-bits */ +#define XFS_IFORK_EXTCNT_MAXU32 ((xfs_aextnum_t)0xffffffff) /* Unsigned 32-bits */ +#define XFS_IFORK_EXTCNT_MAXS32 ((xfs_extnum_t)0x7fffffff) /* Signed 32-bits */ +#define XFS_IFORK_EXTCNT_MAXS16 ((xfs_aextnum_t)0x7fff) /* Signed 16-bits */ + + /* * Values and macros for delayed-allocation startblock fields. */ diff --git a/fs/xfs/libxfs/xfs_inode_buf.c b/fs/xfs/libxfs/xfs_inode_buf.c index 0ab332c913c4..1b27095b423d 100644 --- a/fs/xfs/libxfs/xfs_inode_buf.c +++ b/fs/xfs/libxfs/xfs_inode_buf.c @@ -747,7 +747,7 @@ xfs_inode_validate_extsize( if (extsize_bytes % blocksize_bytes) return __this_address; - if (extsize > MAXEXTLEN) + if (extsize > XFS_MAX_EXTLEN) return __this_address; if (!rt_flag && extsize > mp->m_sb.sb_agblocks / 2) @@ -804,7 +804,7 @@ xfs_inode_validate_cowextsize( if (cowextsize_bytes % mp->m_sb.sb_blocksize) return __this_address; - if (cowextsize > MAXEXTLEN) + if (cowextsize > XFS_MAX_EXTLEN) return __this_address; if (cowextsize > mp->m_sb.sb_agblocks / 2) diff --git a/fs/xfs/libxfs/xfs_rtbitmap.c b/fs/xfs/libxfs/xfs_rtbitmap.c index 7b70ac58a1dc..0ed94079f72c 100644 --- a/fs/xfs/libxfs/xfs_rtbitmap.c +++ b/fs/xfs/libxfs/xfs_rtbitmap.c @@ -1015,7 +1015,7 @@ xfs_rtfree_extent( /* * Free some blocks in the realtime subvolume. rtbno and rtlen are in units of * rt blocks, not rt extents; must be aligned to the rt extent size; and rtlen - * cannot exceed MAXEXTLEN. + * cannot exceed XFS_MAX_EXTLEN. */ int xfs_rtfree_blocks( @@ -1028,7 +1028,7 @@ xfs_rtfree_blocks( xfs_filblks_t len; xfs_extlen_t mod; - ASSERT(rtlen <= MAXEXTLEN); + ASSERT(rtlen <= XFS_MAX_EXTLEN); len = div_u64_rem(rtlen, mp->m_sb.sb_rextsize, &mod); if (mod) { diff --git a/fs/xfs/libxfs/xfs_swapext.c b/fs/xfs/libxfs/xfs_swapext.c index 36c918776ba0..6a5564e534eb 100644 --- a/fs/xfs/libxfs/xfs_swapext.c +++ b/fs/xfs/libxfs/xfs_swapext.c @@ -757,7 +757,7 @@ can_merge( if (b1->br_startoff + b1->br_blockcount == b2->br_startoff && b1->br_startblock + b1->br_blockcount == b2->br_startblock && b1->br_state == b2->br_state && - b1->br_blockcount + b2->br_blockcount <= MAXEXTLEN) + b1->br_blockcount + b2->br_blockcount <= XFS_MAX_EXTLEN) return true; return false; @@ -799,7 +799,7 @@ delta_nextents_step( state |= CRIGHT_CONTIG; if ((state & CBOTH_CONTIG) == CBOTH_CONTIG && left->br_startblock + curr->br_startblock + - right->br_startblock > MAXEXTLEN) + right->br_startblock > XFS_MAX_EXTLEN) state &= ~CRIGHT_CONTIG; if (nhole) @@ -810,7 +810,7 @@ delta_nextents_step( state |= NRIGHT_CONTIG; if ((state & NBOTH_CONTIG) == NBOTH_CONTIG && left->br_startblock + new->br_startblock + - right->br_startblock > MAXEXTLEN) + right->br_startblock > XFS_MAX_EXTLEN) state &= ~NRIGHT_CONTIG; switch (state & (CLEFT_CONTIG | CRIGHT_CONTIG | CHOLE)) { diff --git a/fs/xfs/libxfs/xfs_trans_resv.c b/fs/xfs/libxfs/xfs_trans_resv.c index b3de538ea7ce..0c165bf3c357 100644 --- a/fs/xfs/libxfs/xfs_trans_resv.c +++ b/fs/xfs/libxfs/xfs_trans_resv.c @@ -209,8 +209,8 @@ xfs_calc_inode_chunk_res( /* * Per-extent log reservation for the btree changes involved in freeing or * allocating a realtime extent. We have to be able to log as many rtbitmap - * blocks as needed to mark inuse MAXEXTLEN blocks' worth of realtime extents, - * as well as the realtime summary block. + * blocks as needed to mark inuse XFS_MAX_EXTLEN blocks' worth of realtime + * extents, as well as the realtime summary block. */ static unsigned int xfs_rtalloc_log_count( @@ -220,7 +220,7 @@ xfs_rtalloc_log_count( unsigned int blksz = XFS_FSB_TO_B(mp, 1); unsigned int rtbmp_bytes; - rtbmp_bytes = (MAXEXTLEN / mp->m_sb.sb_rextsize) / NBBY; + rtbmp_bytes = (XFS_MAX_EXTLEN / mp->m_sb.sb_rextsize) / NBBY; return (howmany(rtbmp_bytes, blksz) + 1) * num_ops; } @@ -279,7 +279,7 @@ xfs_refcount_log_reservation( * the inode's bmap btree: max depth * block size * the agfs of the ags from which the extents are allocated: 2 * sector * the superblock free block counter: sector size - * the realtime bitmap: ((MAXEXTLEN / rtextsize) / NBBY) bytes + * the realtime bitmap: ((XFS_MAX_EXTLEN / rtextsize) / NBBY) bytes * the realtime summary: 1 block * the allocation btrees: 2 trees * (2 * max depth - 1) * block size * And the bmap_finish transaction can free bmap blocks in a join (t3): @@ -334,7 +334,7 @@ xfs_calc_write_reservation( * the agf for each of the ags: 2 * sector size * the agfl for each of the ags: 2 * sector size * the super block to reflect the freed blocks: sector size - * the realtime bitmap: 2 exts * ((MAXEXTLEN / rtextsize) / NBBY) bytes + * the realtime bitmap: 2 exts * ((XFS_MAX_EXTLEN / rtextsize) / NBBY) bytes * the realtime summary: 2 exts * 1 block * worst case split in allocation btrees per extent assuming 2 extents: * 2 exts * 2 trees * (2 * max depth - 1) * block size diff --git a/fs/xfs/scrub/bmap.c b/fs/xfs/scrub/bmap.c index 5fcaa2518799..d57509090788 100644 --- a/fs/xfs/scrub/bmap.c +++ b/fs/xfs/scrub/bmap.c @@ -427,7 +427,7 @@ xchk_bmap_iextent( irec->br_startoff); /* Make sure the extent points to a valid place. */ - if (irec->br_blockcount > MAXEXTLEN) + if (irec->br_blockcount > XFS_MAX_EXTLEN) xchk_fblock_set_corrupt(info->sc, info->whichfork, irec->br_startoff); if (info->is_rt && diff --git a/fs/xfs/scrub/bmap_repair.c b/fs/xfs/scrub/bmap_repair.c index 471f67d7acb1..6f1edadbadac 100644 --- a/fs/xfs/scrub/bmap_repair.c +++ b/fs/xfs/scrub/bmap_repair.c @@ -92,7 +92,7 @@ xrep_bmap_from_rmap( do { irec.br_blockcount = min_t(xfs_filblks_t, blockcount, - MAXEXTLEN); + XFS_MAX_EXTLEN); xfs_bmbt_disk_set_all(&rbe, &irec); trace_xrep_bmap_found(rb->sc->ip, rb->whichfork, &irec); diff --git a/fs/xfs/scrub/repair.c b/fs/xfs/scrub/repair.c index 5ea55a4f4c2b..67268a534a83 100644 --- a/fs/xfs/scrub/repair.c +++ b/fs/xfs/scrub/repair.c @@ -1127,7 +1127,7 @@ xrep_reap_extent( xfs_agblock_t agbno_next = agbno + len; int error = 0; - ASSERT(len <= MAXEXTLEN); + ASSERT(len <= XFS_MAX_EXTLEN); if (sc->ip != NULL) { /* diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c index f43f1d434fe2..45a86b36c9dc 100644 --- a/fs/xfs/xfs_bmap_util.c +++ b/fs/xfs/xfs_bmap_util.c @@ -120,14 +120,14 @@ xfs_bmap_rtalloc( */ ralen = ap->length / mp->m_sb.sb_rextsize; /* - * If the old value was close enough to MAXEXTLEN that + * If the old value was close enough to XFS_MAX_EXTLEN that * we rounded up to it, cut it back so it's valid again. * Note that if it's a really large request (bigger than - * MAXEXTLEN), we don't hear about that number, and can't + * XFS_MAX_EXTLEN), we don't hear about that number, and can't * adjust the starting point to match it. */ - if (ralen * mp->m_sb.sb_rextsize >= MAXEXTLEN) - ralen = MAXEXTLEN / mp->m_sb.sb_rextsize; + if (ralen * mp->m_sb.sb_rextsize >= XFS_MAX_EXTLEN) + ralen = XFS_MAX_EXTLEN / mp->m_sb.sb_rextsize; /* * Lock out modifications to both the RT bitmap and summary inodes @@ -841,9 +841,11 @@ xfs_alloc_file_space( * count, hence we need to limit the number of blocks we are * trying to reserve to avoid an overflow. We can't allocate * more than @nimaps extents, and an extent is limited on disk - * to MAXEXTLEN (21 bits), so use that to enforce the limit. + * to XFS_MAX_EXTLEN (21 bits), so use that to enforce the + * limit. */ - resblks = min_t(xfs_fileoff_t, (e - s), (MAXEXTLEN * nimaps)); + resblks = min_t(xfs_fileoff_t, (e - s), + (XFS_MAX_EXTLEN * nimaps)); if (unlikely(rt)) { dblocks = XFS_DIOSTRAT_SPACE_RES(mp, 0); rblocks = resblks; diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c index 2c8eee2fe5be..e5e5d1482ff2 100644 --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -399,7 +399,7 @@ xfs_iomap_prealloc_size( */ plen = prev.br_blockcount; while (xfs_iext_prev_extent(ifp, &ncur, &got)) { - if (plen > MAXEXTLEN / 2 || + if (plen > XFS_MAX_EXTLEN / 2 || isnullstartblock(got.br_startblock) || got.br_startoff + got.br_blockcount != prev.br_startoff || got.br_startblock + got.br_blockcount != prev.br_startblock) @@ -411,23 +411,23 @@ xfs_iomap_prealloc_size( /* * If the size of the extents is greater than half the maximum extent * length, then use the current offset as the basis. This ensures that - * for large files the preallocation size always extends to MAXEXTLEN - * rather than falling short due to things like stripe unit/width - * alignment of real extents. + * for large files the preallocation size always extends to + * XFS_MAX_EXTLEN rather than falling short due to things like stripe + * unit/width alignment of real extents. */ alloc_blocks = plen * 2; - if (alloc_blocks > MAXEXTLEN) + if (alloc_blocks > XFS_MAX_EXTLEN) alloc_blocks = XFS_B_TO_FSB(mp, offset); qblocks = alloc_blocks; /* - * MAXEXTLEN is not a power of two value but we round the prealloc down - * to the nearest power of two value after throttling. To prevent the - * round down from unconditionally reducing the maximum supported - * prealloc size, we round up first, apply appropriate throttling, - * round down and cap the value to MAXEXTLEN. + * XFS_MAX_EXTLEN is not a power of two value but we round the prealloc + * down to the nearest power of two value after throttling. To prevent + * the round down from unconditionally reducing the maximum supported + * prealloc size, we round up first, apply appropriate throttling, round + * down and cap the value to XFS_MAX_EXTLEN. */ - alloc_blocks = XFS_FILEOFF_MIN(roundup_pow_of_two(MAXEXTLEN), + alloc_blocks = XFS_FILEOFF_MIN(roundup_pow_of_two(XFS_MAX_EXTLEN), alloc_blocks); freesp = percpu_counter_read_positive(&mp->m_fdblocks); @@ -475,14 +475,14 @@ xfs_iomap_prealloc_size( */ if (alloc_blocks) alloc_blocks = rounddown_pow_of_two(alloc_blocks); - if (alloc_blocks > MAXEXTLEN) - alloc_blocks = MAXEXTLEN; + if (alloc_blocks > XFS_MAX_EXTLEN) + alloc_blocks = XFS_MAX_EXTLEN; /* * If we are still trying to allocate more space than is * available, squash the prealloc hard. This can happen if we * have a large file on a small filesystem and the above - * lowspace thresholds are smaller than MAXEXTLEN. + * lowspace thresholds are smaller than XFS_MAX_EXTLEN. */ while (alloc_blocks && alloc_blocks >= freesp) alloc_blocks >>= 4; -- 2.30.2