[PATCH 06/47] xfs: during btree split, save new block key & ptr for future insertion

Darrick J. Wong
2016-07-21T04:56:48Z

When a btree block has to be split, we pass the new block's ptr from
xfs_btree_split() back to xfs_btree_insert() via a pointer parameter;
however, we pass the block's key through the cursor's record. It is a
little weird to "initialize" a record from a key since the non-key
attributes will have garbage values.

When we go to add support for interval queries, we have to be able to
pass the lowest and highest keys accessible via a pointer. There's no
clean way to pass this back through the cursor's record field.
Therefore, pass the key directly back to xfs_btree_insert() the same
way that we pass the btree_ptr.

As a bonus, we no longer need init_rec_from_key and can drop it from the
codebase.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
fs/xfs/libxfs/xfs_alloc_btree.c | 12 -----------
fs/xfs/libxfs/xfs_bmap_btree.c | 12 -----------
fs/xfs/libxfs/xfs_btree.c | 40 +++++++++++++++++++-------------------
fs/xfs/libxfs/xfs_btree.h | 2 --
fs/xfs/libxfs/xfs_ialloc_btree.c | 10 ----------
5 files changed, 20 insertions(+), 56 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_alloc_btree.c b/fs/xfs/libxfs/xfs_alloc_btree.c
index d9b42425..5ba2dac 100644
--- a/fs/xfs/libxfs/xfs_alloc_btree.c
+++ b/fs/xfs/libxfs/xfs_alloc_btree.c
@@ -212,17 +212,6 @@ xfs_allocbt_init_key_from_rec(
}

STATIC void
-xfs_allocbt_init_rec_from_key(
- union xfs_btree_key *key,
- union xfs_btree_rec *rec)
-{
- ASSERT(key->alloc.ar_startblock != 0);
-
- rec->alloc.ar_startblock = key->alloc.ar_startblock;
- rec->alloc.ar_blockcount = key->alloc.ar_blockcount;
-}
-
-STATIC void
xfs_allocbt_init_rec_from_cur(
struct xfs_btree_cur *cur,
union xfs_btree_rec *rec)
@@ -406,7 +395,6 @@ static const struct xfs_btree_ops xfs_allocbt_ops = {
.get_minrecs = xfs_allocbt_get_minrecs,
.get_maxrecs = xfs_allocbt_get_maxrecs,
.init_key_from_rec = xfs_allocbt_init_key_from_rec,
- .init_rec_from_key = xfs_allocbt_init_rec_from_key,
.init_rec_from_cur = xfs_allocbt_init_rec_from_cur,
.init_ptr_from_cur = xfs_allocbt_init_ptr_from_cur,
.key_diff = xfs_allocbt_key_diff,
diff --git a/fs/xfs/libxfs/xfs_bmap_btree.c b/fs/xfs/libxfs/xfs_bmap_btree.c
index db0c71e..714b387 100644
--- a/fs/xfs/libxfs/xfs_bmap_btree.c
+++ b/fs/xfs/libxfs/xfs_bmap_btree.c
@@ -600,17 +600,6 @@ xfs_bmbt_init_key_from_rec(
}

STATIC void
-xfs_bmbt_init_rec_from_key(
- union xfs_btree_key *key,
- union xfs_btree_rec *rec)
-{
- ASSERT(key->bmbt.br_startoff != 0);
-
- xfs_bmbt_disk_set_allf(&rec->bmbt, be64_to_cpu(key->bmbt.br_startoff),
- 0, 0, XFS_EXT_NORM);
-}
-
-STATIC void
xfs_bmbt_init_rec_from_cur(
struct xfs_btree_cur *cur,
union xfs_btree_rec *rec)
@@ -760,7 +749,6 @@ static const struct xfs_btree_ops xfs_bmbt_ops = {
.get_minrecs = xfs_bmbt_get_minrecs,
.get_dmaxrecs = xfs_bmbt_get_dmaxrecs,
.init_key_from_rec = xfs_bmbt_init_key_from_rec,
- .init_rec_from_key = xfs_bmbt_init_rec_from_key,
.init_rec_from_cur = xfs_bmbt_init_rec_from_cur,
.init_ptr_from_cur = xfs_bmbt_init_ptr_from_cur,
.key_diff = xfs_bmbt_key_diff,
diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c
index f5ff95a..8d8e362 100644
--- a/fs/xfs/libxfs/xfs_btree.c
+++ b/fs/xfs/libxfs/xfs_btree.c
@@ -2858,10 +2858,9 @@ xfs_btree_make_block_unfull(
int *index, /* new tree index */
union xfs_btree_ptr *nptr, /* new btree ptr */
struct xfs_btree_cur **ncur, /* new btree cursor */
- union xfs_btree_rec *nrec, /* new record */
+ union xfs_btree_key *key, /* key of new block */
int *stat)
{
- union xfs_btree_key key; /* new btree key value */
int error = 0;

if ((cur->bc_flags & XFS_BTREE_ROOT_IN_INODE) &&
@@ -2907,13 +2906,12 @@ xfs_btree_make_block_unfull(
* If this works we have to re-set our variables because we
* could be in a different block now.
*/
- error = xfs_btree_split(cur, level, nptr, &key, ncur, stat);
+ error = xfs_btree_split(cur, level, nptr, key, ncur, stat);
if (error || *stat == 0)
return error;

*index = cur->bc_ptrs[level];
- cur->bc_ops->init_rec_from_key(&key, nrec);
return 0;
}

@@ -2926,16 +2924,16 @@ xfs_btree_insrec(
struct xfs_btree_cur *cur, /* btree cursor */
int level, /* level to insert record at */
union xfs_btree_ptr *ptrp, /* i/o: block number inserted */
- union xfs_btree_rec *recp, /* i/o: record data inserted */
+ union xfs_btree_rec *rec, /* record to insert */
+ union xfs_btree_key *key, /* i/o: block key for ptrp */
struct xfs_btree_cur **curp, /* output: new cursor replacing cur */
int *stat) /* success/failure */
{
struct xfs_btree_block *block; /* btree block */
struct xfs_buf *bp; /* buffer for block */
- union xfs_btree_key key; /* btree key */
union xfs_btree_ptr nptr; /* new block ptr */
struct xfs_btree_cur *ncur; /* new btree cursor */
- union xfs_btree_rec nrec; /* new record count */
+ union xfs_btree_key nkey; /* new block key */
int optr; /* old key/record index */
int ptr; /* key/record index */
int numrecs;/* number of records */
@@ -2945,7 +2943,7 @@ xfs_btree_insrec(
#endif

XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
- XFS_BTREE_TRACE_ARGIPR(cur, level, *ptrp, recp);
+ XFS_BTREE_TRACE_ARGIPR(cur, level, *ptrp, &rec);

ncur = NULL;

@@ -2970,9 +2968,6 @@ xfs_btree_insrec(
return 0;
}

- /* Make a key out of the record data to be inserted, and save it. */
- cur->bc_ops->init_key_from_rec(&key, recp);
-
optr = ptr;

XFS_BTREE_STATS_INC(cur, insrec);
@@ -2989,10 +2984,10 @@ xfs_btree_insrec(
/* Check that the new entry is being inserted in the right place. */
if (ptr <= numrecs) {
if (level == 0) {
- ASSERT(cur->bc_ops->recs_inorder(cur, recp,
+ ASSERT(cur->bc_ops->recs_inorder(cur, rec,
xfs_btree_rec_addr(cur, ptr, block)));
} else {
- ASSERT(cur->bc_ops->keys_inorder(cur, &key,
+ ASSERT(cur->bc_ops->keys_inorder(cur, key,
xfs_btree_key_addr(cur, ptr, block)));
}
}
@@ -3005,7 +3000,7 @@ xfs_btree_insrec(
xfs_btree_set_ptr_null(cur, &nptr);
if (numrecs == cur->bc_ops->get_maxrecs(cur, level)) {
error = xfs_btree_make_block_unfull(cur, level, numrecs,
- &optr, &ptr, &nptr, &ncur, &nrec, stat);
+ &optr, &ptr, &nptr, &ncur, &nkey, stat);
if (error || *stat == 0)
goto error0;
}
@@ -3055,7 +3050,7 @@ xfs_btree_insrec(
#endif

/* Now put the new data in, bump numrecs and log it. */
- xfs_btree_copy_keys(cur, kp, &key, 1);
+ xfs_btree_copy_keys(cur, kp, key, 1);
xfs_btree_copy_ptrs(cur, pp, ptrp, 1);
numrecs++;
xfs_btree_set_numrecs(block, numrecs);
@@ -3076,7 +3071,7 @@ xfs_btree_insrec(
xfs_btree_shift_recs(cur, rp, 1, numrecs - ptr + 1);

/* Now put the new data in, bump numrecs and log it. */
- xfs_btree_copy_recs(cur, rp, recp, 1);
+ xfs_btree_copy_recs(cur, rp, rec, 1);
xfs_btree_set_numrecs(block, ++numrecs);
xfs_btree_log_recs(cur, bp, ptr, numrecs);
#ifdef DEBUG
@@ -3092,7 +3087,7 @@ xfs_btree_insrec(

/* If we inserted at the start of a block, update the parents' keys. */
if (optr == 1) {
- error = xfs_btree_updkey(cur, &key, level + 1);
+ error = xfs_btree_updkey(cur, key, level + 1);
if (error)
goto error0;
}
@@ -3102,7 +3097,7 @@ xfs_btree_insrec(
* we are at the far right edge of the tree, update it.
*/
if (xfs_btree_is_lastrec(cur, block, level)) {
- cur->bc_ops->update_lastrec(cur, block, recp,
+ cur->bc_ops->update_lastrec(cur, block, rec,
ptr, LASTREC_INSREC);
}

@@ -3112,7 +3107,7 @@ xfs_btree_insrec(
*/
*ptrp = nptr;
if (!xfs_btree_ptr_is_null(cur, &nptr)) {
- *recp = nrec;
+ *key = nkey;
*curp = ncur;
}

@@ -3143,6 +3138,7 @@ xfs_btree_insert(
union xfs_btree_ptr nptr; /* new block number (split result) */
struct xfs_btree_cur *ncur; /* new cursor (split result) */
struct xfs_btree_cur *pcur; /* previous level's cursor */
+ union xfs_btree_key key; /* key of block to insert */
union xfs_btree_rec rec; /* record to insert */

level = 0;
@@ -3150,7 +3146,10 @@ xfs_btree_insert(
pcur = cur;

xfs_btree_set_ptr_null(cur, &nptr);
+
+ /* Make a key out of the record data to be inserted, and save it. */
cur->bc_ops->init_rec_from_cur(cur, &rec);
+ cur->bc_ops->init_key_from_rec(&key, &rec);

/*
* Loop going up the tree, starting at the leaf level.
@@ -3162,7 +3161,8 @@ xfs_btree_insert(
* Insert nrec/nptr into this level of the tree.
* Note if we fail, nptr will be null.
*/
- error = xfs_btree_insrec(pcur, level, &nptr, &rec, &ncur, &i);
+ error = xfs_btree_insrec(pcur, level, &nptr, &rec, &key,
+ &ncur, &i);
if (error) {
if (pcur != cur)
xfs_btree_del_cursor(pcur, XFS_BTREE_ERROR);
diff --git a/fs/xfs/libxfs/xfs_btree.h b/fs/xfs/libxfs/xfs_btree.h
index 785a996..b4f3035 100644
--- a/fs/xfs/libxfs/xfs_btree.h
+++ b/fs/xfs/libxfs/xfs_btree.h
@@ -158,8 +158,6 @@ struct xfs_btree_ops {
/* init values of btree structures */
void (*init_key_from_rec)(union xfs_btree_key *key,
union xfs_btree_rec *rec);
- void (*init_rec_from_key)(union xfs_btree_key *key,
- union xfs_btree_rec *rec);
void (*init_rec_from_cur)(struct xfs_btree_cur *cur,
union xfs_btree_rec *rec);
void (*init_ptr_from_cur)(struct xfs_btree_cur *cur,
diff --git a/fs/xfs/libxfs/xfs_ialloc_btree.c b/fs/xfs/libxfs/xfs_ialloc_btree.c
index 89c21d7..88da2ad 100644
--- a/fs/xfs/libxfs/xfs_ialloc_btree.c
+++ b/fs/xfs/libxfs/xfs_ialloc_btree.c
@@ -146,14 +146,6 @@ xfs_inobt_init_key_from_rec(
}

STATIC void
-xfs_inobt_init_rec_from_key(
- union xfs_btree_key *key,
- union xfs_btree_rec *rec)
-{
- rec->inobt.ir_startino = key->inobt.ir_startino;
-}
-
-STATIC void
xfs_inobt_init_rec_from_cur(
struct xfs_btree_cur *cur,
union xfs_btree_rec *rec)
@@ -314,7 +306,6 @@ static const struct xfs_btree_ops xfs_inobt_ops = {
.get_minrecs = xfs_inobt_get_minrecs,
.get_maxrecs = xfs_inobt_get_maxrecs,
.init_key_from_rec = xfs_inobt_init_key_from_rec,
- .init_rec_from_key = xfs_inobt_init_rec_from_key,
.init_rec_from_cur = xfs_inobt_init_rec_from_cur,
.init_ptr_from_cur = xfs_inobt_init_ptr_from_cur,
.key_diff = xfs_inobt_key_diff,
@@ -336,7 +327,6 @@ static const struct xfs_btree_ops xfs_finobt_ops = {
.get_minrecs = xfs_inobt_get_minrecs,
.get_maxrecs = xfs_inobt_get_maxrecs,
.init_key_from_rec = xfs_inobt_init_key_from_rec,
- .init_rec_from_key = xfs_inobt_init_rec_from_key,
.init_rec_from_cur = xfs_inobt_init_rec_from_cur,
.init_ptr_from_cur = xfs_finobt_init_ptr_from_cur,
.key_diff = xfs_inobt_key_diff,