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Diffstat (limited to 'db2/btree/bt_rec.c')
-rw-r--r--db2/btree/bt_rec.c113
1 files changed, 79 insertions, 34 deletions
diff --git a/db2/btree/bt_rec.c b/db2/btree/bt_rec.c
index c0b7c8a..90ee137 100644
--- a/db2/btree/bt_rec.c
+++ b/db2/btree/bt_rec.c
@@ -8,7 +8,7 @@
#include "config.h"
#ifndef lint
-static const char sccsid[] = "@(#)bt_rec.c 10.17 (Sleepycat) 11/2/97";
+static const char sccsid[] = "@(#)bt_rec.c 10.18 (Sleepycat) 12/15/97";
#endif /* not lint */
#ifndef NO_SYSTEM_INCLUDES
@@ -69,10 +69,17 @@ __bam_pg_alloc_recover(logp, dbtp, lsnp, redo, info)
*/
pgno = PGNO_METADATA;
if ((ret = memp_fget(mpf, &pgno, 0, &meta)) != 0) {
+ /* The metadata page must always exist. */
(void)__db_pgerr(file_dbp, pgno);
goto out;
}
if ((ret = memp_fget(mpf, &argp->pgno, DB_MPOOL_CREATE, &pagep)) != 0) {
+ /*
+ * We specify creation and check for it later, because this
+ * operation was supposed to create the page, and even in
+ * the undo case it's going to get linked onto the freelist
+ * which we're also fixing up.
+ */
(void)__db_pgerr(file_dbp, argp->pgno);
(void)memp_fput(mpf, meta, 0);
goto out;
@@ -162,6 +169,15 @@ __bam_pg_free_recover(logp, dbtp, lsnp, redo, info)
* we're undoing the operation, we get the page and restore its header.
*/
if ((ret = memp_fget(mpf, &argp->pgno, 0, &pagep)) != 0) {
+ /*
+ * We don't automatically create the page. The only way the
+ * page might not exist is if the alloc never happened, and
+ * the only way the alloc might never have happened is if we
+ * are undoing, in which case there's no reason to create the
+ * page.
+ */
+ if (!redo)
+ goto done;
(void)__db_pgerr(file_dbp, argp->pgno);
goto out;
}
@@ -192,6 +208,7 @@ __bam_pg_free_recover(logp, dbtp, lsnp, redo, info)
*/
pgno = PGNO_METADATA;
if ((ret = memp_fget(mpf, &pgno, 0, &meta)) != 0) {
+ /* The metadata page must always exist. */
(void)__db_pgerr(file_dbp, pgno);
goto out;
}
@@ -217,7 +234,7 @@ __bam_pg_free_recover(logp, dbtp, lsnp, redo, info)
goto out;
}
- *lsnp = argp->prev_lsn;
+done: *lsnp = argp->prev_lsn;
ret = 0;
out: REC_CLOSE;
@@ -389,7 +406,7 @@ __bam_split_recover(logp, dbtp, lsnp, redo, info)
* interest only if it wasn't a root split -- inserting a new
* page in the tree requires that any following page have its
* previous-page pointer updated to our new page. The next
- * page had better exist.
+ * page must exist because we're redoing the operation.
*/
if (!rootsplit && !IS_ZERO_LSN(argp->nlsn)) {
if ((ret = memp_fget(mpf, &argp->npgno, 0, &np)) != 0) {
@@ -409,12 +426,14 @@ __bam_split_recover(logp, dbtp, lsnp, redo, info)
} else {
/*
* If the split page is wrong, replace its contents with the
- * logged page contents. The split page had better exist.
+ * logged page contents. If the page doesn't exist, it means
+ * that the create of the page never happened, nor did any of
+ * the adds onto the page that caused the split, and there's
+ * really no undo-ing to be done.
*/
if ((ret = memp_fget(mpf, &pgno, 0, &pp)) != 0) {
- (void)__db_pgerr(file_dbp, pgno);
pp = NULL;
- goto out;
+ goto lrundo;
}
if (log_compare(lsnp, &LSN(pp)) == 0) {
memcpy(pp, argp->pg.data, argp->pg.size);
@@ -424,13 +443,14 @@ __bam_split_recover(logp, dbtp, lsnp, redo, info)
}
/*
- * If it's a root split and the left child ever existed, put
- * it on the free list. (If it's not a root split, we just
- * updated the left page -- it's the same as the split page.)
- * If the right child ever existed, root split or not, put it
- * on the free list.
+ * If it's a root split and the left child ever existed, update
+ * its LSN. (If it's not a root split, we've updated the left
+ * page already -- it's the same as the split page.) If the
+ * right child ever existed, root split or not, update its LSN.
+ * The undo of the page allocation(s) will restore them to the
+ * free list.
*/
- if ((rootsplit && lp != NULL) || rp != NULL) {
+lrundo: if ((rootsplit && lp != NULL) || rp != NULL) {
if (rootsplit && lp != NULL &&
log_compare(lsnp, &LSN(lp)) == 0) {
lp->lsn = argp->llsn;
@@ -453,14 +473,14 @@ __bam_split_recover(logp, dbtp, lsnp, redo, info)
* Finally, undo the next-page link if necessary. This is of
* interest only if it wasn't a root split -- inserting a new
* page in the tree requires that any following page have its
- * previous-page pointer updated to our new page. The next
- * page had better exist.
+ * previous-page pointer updated to our new page. Since it's
+ * possible that the next-page never existed, we ignore it as
+ * if there's nothing to undo.
*/
if (!rootsplit && !IS_ZERO_LSN(argp->nlsn)) {
if ((ret = memp_fget(mpf, &argp->npgno, 0, &np)) != 0) {
- (void)__db_pgerr(file_dbp, argp->npgno);
np = NULL;
- goto out;
+ goto done;
}
if (log_compare(lsnp, &LSN(np)) == 0) {
PREV_PGNO(np) = argp->left;
@@ -472,8 +492,8 @@ __bam_split_recover(logp, dbtp, lsnp, redo, info)
}
}
-done: ret = 0;
- *lsnp = argp->prev_lsn;
+done: *lsnp = argp->prev_lsn;
+ ret = 0;
if (0) {
fatal: (void)__db_panic(file_dbp);
@@ -525,8 +545,8 @@ __bam_rsplit_recover(logp, dbtp, lsnp, redo, info)
/* Fix the root page. */
pgno = PGNO_ROOT;
if ((ret = memp_fget(mpf, &pgno, 0, &pagep)) != 0) {
+ /* The root page must always exist. */
__db_pgerr(file_dbp, pgno);
- pagep = NULL;
goto out;
}
modified = 0;
@@ -554,10 +574,15 @@ __bam_rsplit_recover(logp, dbtp, lsnp, redo, info)
goto out;
}
- /* Fix the page copied over the root page. */
+ /*
+ * Fix the page copied over the root page. It's possible that the
+ * page never made it to disk, so if we're undo-ing and the page
+ * doesn't exist, it's okay and there's nothing further to do.
+ */
if ((ret = memp_fget(mpf, &argp->pgno, 0, &pagep)) != 0) {
+ if (!redo)
+ goto done;
(void)__db_pgerr(file_dbp, argp->pgno);
- pagep = NULL;
goto out;
}
modified = 0;
@@ -577,8 +602,8 @@ __bam_rsplit_recover(logp, dbtp, lsnp, redo, info)
goto out;
}
+done: *lsnp = argp->prev_lsn;
ret = 0;
- *lsnp = argp->prev_lsn;
out: REC_CLOSE;
}
@@ -607,9 +632,11 @@ __bam_adj_recover(logp, dbtp, lsnp, redo, info)
REC_PRINT(__bam_adj_print);
REC_INTRO(__bam_adj_read);
+ /* Get the page; if it never existed and we're undoing, we're done. */
if ((ret = memp_fget(mpf, &argp->pgno, 0, &pagep)) != 0) {
+ if (!redo)
+ goto done;
(void)__db_pgerr(file_dbp, argp->pgno);
- pagep = NULL;
goto out;
}
@@ -633,8 +660,11 @@ __bam_adj_recover(logp, dbtp, lsnp, redo, info)
LSN(pagep) = argp->lsn;
modified = 1;
}
- if ((ret = memp_fput(mpf, pagep, modified ? DB_MPOOL_DIRTY : 0)) == 0)
- *lsnp = argp->prev_lsn;
+ if ((ret = memp_fput(mpf, pagep, modified ? DB_MPOOL_DIRTY : 0)) != 0)
+ goto out;
+
+done: *lsnp = argp->prev_lsn;
+ ret = 0;
if (0) {
err: (void)memp_fput(mpf, pagep, 0);
@@ -667,9 +697,11 @@ __bam_cadjust_recover(logp, dbtp, lsnp, redo, info)
REC_PRINT(__bam_cadjust_print);
REC_INTRO(__bam_cadjust_read);
+ /* Get the page; if it never existed and we're undoing, we're done. */
if ((ret = memp_fget(mpf, &argp->pgno, 0, &pagep)) != 0) {
+ if (!redo)
+ goto done;
(void)__db_pgerr(file_dbp, argp->pgno);
- pagep = NULL;
goto out;
}
@@ -708,8 +740,11 @@ __bam_cadjust_recover(logp, dbtp, lsnp, redo, info)
LSN(pagep) = argp->lsn;
modified = 1;
}
- if ((ret = memp_fput(mpf, pagep, modified ? DB_MPOOL_DIRTY : 0)) == 0)
- *lsnp = argp->prev_lsn;
+ if ((ret = memp_fput(mpf, pagep, modified ? DB_MPOOL_DIRTY : 0)) != 0)
+ goto out;
+
+done: *lsnp = argp->prev_lsn;
+ ret = 0;
out: REC_CLOSE;
}
@@ -738,9 +773,11 @@ __bam_cdel_recover(logp, dbtp, lsnp, redo, info)
REC_PRINT(__bam_cdel_print);
REC_INTRO(__bam_cdel_read);
+ /* Get the page; if it never existed and we're undoing, we're done. */
if ((ret = memp_fget(mpf, &argp->pgno, 0, &pagep)) != 0) {
+ if (!redo)
+ goto done;
(void)__db_pgerr(file_dbp, argp->pgno);
- pagep = NULL;
goto out;
}
@@ -760,8 +797,11 @@ __bam_cdel_recover(logp, dbtp, lsnp, redo, info)
LSN(pagep) = argp->lsn;
modified = 1;
}
- if ((ret = memp_fput(mpf, pagep, modified ? DB_MPOOL_DIRTY : 0)) == 0)
- *lsnp = argp->prev_lsn;
+ if ((ret = memp_fput(mpf, pagep, modified ? DB_MPOOL_DIRTY : 0)) != 0)
+ goto out;
+
+done: *lsnp = argp->prev_lsn;
+ ret = 0;
out: REC_CLOSE;
}
@@ -793,9 +833,11 @@ __bam_repl_recover(logp, dbtp, lsnp, redo, info)
REC_PRINT(__bam_repl_print);
REC_INTRO(__bam_repl_read);
+ /* Get the page; if it never existed and we're undoing, we're done. */
if ((ret = memp_fget(mpf, &argp->pgno, 0, &pagep)) != 0) {
+ if (!redo)
+ goto done;
(void)__db_pgerr(file_dbp, argp->pgno);
- pagep = NULL;
goto out;
}
bk = GET_BKEYDATA(pagep, argp->indx);
@@ -860,8 +902,11 @@ __bam_repl_recover(logp, dbtp, lsnp, redo, info)
LSN(pagep) = argp->lsn;
modified = 1;
}
- if ((ret = memp_fput(mpf, pagep, modified ? DB_MPOOL_DIRTY : 0)) == 0)
- *lsnp = argp->prev_lsn;
+ if ((ret = memp_fput(mpf, pagep, modified ? DB_MPOOL_DIRTY : 0)) != 0)
+ goto out;
+
+done: *lsnp = argp->prev_lsn;
+ ret = 0;
if (0) {
err: (void)memp_fput(mpf, pagep, 0);
generated by cgit v1.1 at 2024-12-28 11:01:51 +0000