[PATCH V4 20/20] xfsprogs: Define max extent length based on on-disk format definition

Chandan Babu R
2021-12-14T08:50:34Z

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_BMBT_EXTLEN.

Suggested-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Chandan Babu R <chandan.babu@oracle.com>
---
db/metadump.c | 2 +-
libxfs/xfs_bmap.c | 53 +++++++++++++++++++++--------------------
libxfs/xfs_format.h | 23 +++++++++---------
libxfs/xfs_inode_buf.c | 4 ++--
libxfs/xfs_trans_resv.c | 10 ++++----
mkfs/xfs_mkfs.c | 6 ++---
repair/phase4.c | 2 +-
7 files changed, 51 insertions(+), 49 deletions(-)

diff --git a/db/metadump.c b/db/metadump.c
index 8a9aec75..3ed4d81a 100644
--- a/db/metadump.c
+++ b/db/metadump.c
@@ -20,7 +20,7 @@
#include "field.h"
#include "dir2.h"

-#define DEFAULT_MAX_EXT_SIZE MAXEXTLEN
+#define DEFAULT_MAX_EXT_SIZE XFS_MAX_BMBT_EXTLEN

/* copy all metadata structures to/from a file */

diff --git a/libxfs/xfs_bmap.c b/libxfs/xfs_bmap.c
index 9dd24678..ac66a33d 100644
--- a/libxfs/xfs_bmap.c
+++ b/libxfs/xfs_bmap.c
@@ -536,7 +536,7 @@ __xfs_bmap_add_free(

ASSERT(bno != NULLFSBLOCK);
ASSERT(len > 0);
- ASSERT(len <= MAXEXTLEN);
+ ASSERT(len <= XFS_MAX_BMBT_EXTLEN);
ASSERT(!isnullstartblock(bno));
agno = XFS_FSB_TO_AGNO(mp, bno);
agbno = XFS_FSB_TO_AGBNO(mp, bno);
@@ -1493,7 +1493,7 @@ 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_BMBT_EXTLEN)
state |= BMAP_LEFT_CONTIG;

/*
@@ -1511,13 +1511,13 @@ 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_BMBT_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_BMBT_EXTLEN))
state |= BMAP_RIGHT_CONTIG;

error = 0;
@@ -2041,7 +2041,7 @@ 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_BMBT_EXTLEN)
state |= BMAP_LEFT_CONTIG;

/*
@@ -2059,13 +2059,13 @@ 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_BMBT_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_BMBT_EXTLEN))
state |= BMAP_RIGHT_CONTIG;

/*
@@ -2551,15 +2551,15 @@ 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_BMBT_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_BMBT_EXTLEN &&
(!(state & BMAP_LEFT_CONTIG) ||
(left.br_blockcount + new->br_blockcount +
- right.br_blockcount <= MAXEXTLEN)))
+ right.br_blockcount <= XFS_MAX_BMBT_EXTLEN)))
state |= BMAP_RIGHT_CONTIG;

/*
@@ -2702,17 +2702,17 @@ 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_BMBT_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_BMBT_EXTLEN &&
(!(state & BMAP_LEFT_CONTIG) ||
left.br_blockcount + new->br_blockcount +
- right.br_blockcount <= MAXEXTLEN))
+ right.br_blockcount <= XFS_MAX_BMBT_EXTLEN))
state |= BMAP_RIGHT_CONTIG;

error = 0;
@@ -2947,15 +2947,15 @@ 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
+ * XFS_MAX_BMBT_EXTLEN. In that case, reduce the size by an extsz so that it pulls
+ * the length back under XFS_MAX_BMBT_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_BMBT_EXTLEN)
align_alen -= extsz;
- ASSERT(align_alen <= MAXEXTLEN);
+ ASSERT(align_alen <= XFS_MAX_BMBT_EXTLEN);

/*
* If the previous block overlaps with this proposed allocation
@@ -3045,9 +3045,9 @@ xfs_bmap_extsize_align(
return -EINVAL;
} else {
ASSERT(orig_off >= align_off);
- /* see MAXEXTLEN handling above */
+ /* see XFS_MAX_BMBT_EXTLEN handling above */
ASSERT(orig_end <= align_off + align_alen ||
- align_alen + extsz > MAXEXTLEN);
+ align_alen + extsz > XFS_MAX_BMBT_EXTLEN);
}

#ifdef DEBUG
@@ -4012,7 +4012,7 @@ 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_BMBT_EXTLEN);
if (!eof)
alen = XFS_FILBLKS_MIN(alen, got->br_startoff - aoff);
if (prealloc && alen >= len)
@@ -4145,7 +4145,7 @@ 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_BMBT_EXTLEN);
if (!bma->eof)
bma->length = XFS_FILBLKS_MIN(bma->length,
bma->got.br_startoff - bma->offset);
@@ -4465,8 +4465,8 @@ 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_BMBT_EXTLEN)
+ bma.length = XFS_MAX_BMBT_EXTLEN;
else
bma.length = len;

@@ -4601,7 +4601,8 @@ 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_BMBT_EXTLEN);
bma.minleft = xfs_bmapi_minleft(tp, ip, whichfork);

/*
@@ -4682,7 +4683,7 @@ 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_BMBT_EXTLEN);
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
ASSERT(!(flags & ~(XFS_BMAPI_ATTRFORK | XFS_BMAPI_PREALLOC |
XFS_BMAPI_NORMAP)));
@@ -5682,7 +5683,7 @@ 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_BMBT_EXTLEN))
return false;

return true;
diff --git a/libxfs/xfs_format.h b/libxfs/xfs_format.h
index 0ed9d5ac..ac6aa23e 100644
--- a/libxfs/xfs_format.h
+++ b/libxfs/xfs_format.h
@@ -1073,15 +1073,6 @@ enum xfs_dinode_fmt {
{ XFS_DINODE_FMT_BTREE, "btree" }, \
{ XFS_DINODE_FMT_UUID, "uuid" }

-/*
- * Max values for extlen, extnum, aextnum.
- */
-#define MAXEXTLEN ((xfs_extlen_t)0x1fffff) /* 21 bits */
-#define XFS_MAX_EXTCNT_DATA_FORK ((xfs_extnum_t)0xffffffffffff) /* Unsigned 48-bits */
-#define XFS_MAX_EXTCNT_ATTR_FORK ((xfs_aextnum_t)0xffffffff) /* Unsigned 32-bits */
-#define XFS_MAX_EXTCNT_DATA_FORK_OLD ((xfs_extnum_t)0x7fffffff) /* Signed 32-bits */
-#define XFS_MAX_EXTCNT_ATTR_FORK_OLD ((xfs_aextnum_t)0x7fff) /* Signed 16-bits */
-
/*
* Inode minimum and maximum sizes.
*/
@@ -1810,8 +1801,18 @@ typedef struct xfs_bmdr_block {
#define BMBT_STARTBLOCK_BITLEN 52
#define BMBT_BLOCKCOUNT_BITLEN 21

-#define BMBT_STARTOFF_MASK ((1ULL << BMBT_STARTOFF_BITLEN) - 1)
-#define BMBT_BLOCKCOUNT_MASK ((1ULL << BMBT_BLOCKCOUNT_BITLEN) - 1)
+#define BMBT_STARTOFF_MASK ((1ULL << BMBT_STARTOFF_BITLEN) - 1)
+
+/*
+ * Max values for extlen, extnum, aextnum.
+ */
+#define XFS_MAX_BMBT_EXTLEN ((xfs_extlen_t)(1ULL << BMBT_BLOCKCOUNT_BITLEN) - 1)
+#define XFS_MAX_EXTCNT_DATA_FORK ((xfs_extnum_t)0xffffffffffff) /* Unsigned 48-bits */
+#define XFS_MAX_EXTCNT_ATTR_FORK ((xfs_aextnum_t)0xffffffff) /* Unsigned 32-bits */
+#define XFS_MAX_EXTCNT_DATA_FORK_OLD ((xfs_extnum_t)0x7fffffff) /* Signed 32-bits */
+#define XFS_MAX_EXTCNT_ATTR_FORK_OLD ((xfs_aextnum_t)0x7fff) /* Signed 16-bits */
+
+#define BMBT_BLOCKCOUNT_MASK XFS_MAX_BMBT_EXTLEN

/*
* bmbt records have a file offset (block) field that is 54 bits wide, so this
diff --git a/libxfs/xfs_inode_buf.c b/libxfs/xfs_inode_buf.c
index a484e14b..601ca604 100644
--- a/libxfs/xfs_inode_buf.c
+++ b/libxfs/xfs_inode_buf.c
@@ -666,7 +666,7 @@ xfs_inode_validate_extsize(
if (extsize_bytes % blocksize_bytes)
return __this_address;

- if (extsize > MAXEXTLEN)
+ if (extsize > XFS_MAX_BMBT_EXTLEN)
return __this_address;

if (!rt_flag && extsize > mp->m_sb.sb_agblocks / 2)
@@ -723,7 +723,7 @@ xfs_inode_validate_cowextsize(
if (cowextsize_bytes % mp->m_sb.sb_blocksize)
return __this_address;

- if (cowextsize > MAXEXTLEN)
+ if (cowextsize > XFS_MAX_BMBT_EXTLEN)
return __this_address;

if (cowextsize > mp->m_sb.sb_agblocks / 2)
diff --git a/libxfs/xfs_trans_resv.c b/libxfs/xfs_trans_resv.c
index 4fd2c62b..559879e5 100644
--- a/libxfs/xfs_trans_resv.c
+++ b/libxfs/xfs_trans_resv.c
@@ -198,8 +198,8 @@ 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_BMBT_EXTLEN blocks' worth of realtime
+ * extents, as well as the realtime summary block.
*/
static unsigned int
xfs_rtalloc_log_count(
@@ -209,7 +209,7 @@ 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_BMBT_EXTLEN / mp->m_sb.sb_rextsize) / NBBY;
return (howmany(rtbmp_bytes, blksz) + 1) * num_ops;
}

@@ -246,7 +246,7 @@ xfs_rtalloc_log_count(
* 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_BMBT_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):
@@ -298,7 +298,7 @@ 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_BMBT_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/mkfs/xfs_mkfs.c b/mkfs/xfs_mkfs.c
index 6609776f..deb3b070 100644
--- a/mkfs/xfs_mkfs.c
+++ b/mkfs/xfs_mkfs.c
@@ -2399,7 +2399,7 @@ validate_extsize_hint(
fprintf(stderr,
_("illegal extent size hint %lld, must be less than %u.\n"),
(long long)cli->fsx.fsx_extsize,
- min(MAXEXTLEN, mp->m_sb.sb_agblocks / 2));
+ min(XFS_MAX_BMBT_EXTLEN, mp->m_sb.sb_agblocks / 2));
usage();
}

@@ -2422,7 +2422,7 @@ _("illegal extent size hint %lld, must be less than %u.\n"),
fprintf(stderr,
_("illegal extent size hint %lld, must be less than %u and a multiple of %u.\n"),
(long long)cli->fsx.fsx_extsize,
- min(MAXEXTLEN, mp->m_sb.sb_agblocks / 2),
+ min(XFS_MAX_BMBT_EXTLEN, mp->m_sb.sb_agblocks / 2),
mp->m_sb.sb_rextsize);
usage();
}
@@ -2451,7 +2451,7 @@ validate_cowextsize_hint(
fprintf(stderr,
_("illegal CoW extent size hint %lld, must be less than %u.\n"),
(long long)cli->fsx.fsx_cowextsize,
- min(MAXEXTLEN, mp->m_sb.sb_agblocks / 2));
+ min(XFS_MAX_BMBT_EXTLEN, mp->m_sb.sb_agblocks / 2));
usage();
}
}
diff --git a/repair/phase4.c b/repair/phase4.c
index eb043002..8cad2b80 100644
--- a/repair/phase4.c
+++ b/repair/phase4.c
@@ -372,7 +372,7 @@ phase4(xfs_mount_t *mp)
if (rt_start == 0) {
rt_start = bno;
rt_len = 1;
- } else if (rt_len == MAXEXTLEN) {
+ } else if (rt_len == XFS_MAX_BMBT_EXTLEN) {
/*
* large extent case
*/
--
2.30.2