- /*
+ /*
Unix SMB/CIFS implementation.
trivial database library
#include <assert.h>
#include <ccan/build_assert/build_assert.h>
+/* If we were threaded, we could wait for unlock, but we're not, so fail. */
+static enum TDB_ERROR owner_conflict(struct tdb_context *tdb, const char *call)
+{
+ return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_USE_ERROR,
+ "%s: lock owned by another tdb in this process.",
+ call);
+}
+
+/* If we fork, we no longer really own locks. */
+static bool check_lock_pid(struct tdb_context *tdb,
+ const char *call, bool log)
+{
+ /* No locks? No problem! */
+ if (tdb->file->allrecord_lock.count == 0
+ && tdb->file->num_lockrecs == 0) {
+ return true;
+ }
+
+ /* No fork? No problem! */
+ if (tdb->file->locker == getpid()) {
+ return true;
+ }
+
+ if (log) {
+ tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_USE_ERROR,
+ "%s: fork() detected after lock acquisition!"
+ " (%u vs %u)", call, tdb->file->locker, getpid());
+ }
+ return false;
+}
+
static int fcntl_lock(struct tdb_context *tdb,
int rw, off_t off, off_t len, bool waitflag)
{
fl.l_len = len;
fl.l_pid = 0;
+ if (tdb->file->allrecord_lock.count == 0
+ && tdb->file->num_lockrecs == 0) {
+ tdb->file->locker = getpid();
+ }
+
+ add_stat(tdb, lock_lowlevel, 1);
if (waitflag)
- return fcntl(tdb->fd, F_SETLKW, &fl);
- else
- return fcntl(tdb->fd, F_SETLK, &fl);
+ return fcntl(tdb->file->fd, F_SETLKW, &fl);
+ else {
+ add_stat(tdb, lock_nonblock, 1);
+ return fcntl(tdb->file->fd, F_SETLK, &fl);
+ }
}
static int fcntl_unlock(struct tdb_context *tdb, int rw, off_t off, off_t len)
}
if (!found) {
- fprintf(stderr, "Unlock on %u@%u not found!\n",
+ fprintf(stderr, "Unlock on %u@%u not found!",
(int)off, (int)len);
abort();
}
fl.l_len = len;
fl.l_pid = 0;
- return fcntl(tdb->fd, F_SETLKW, &fl);
+ return fcntl(tdb->file->fd, F_SETLKW, &fl);
}
/* a byte range locking function - return 0 on success
- this functions locks/unlocks 1 byte at the specified offset.
+ this functions locks len bytes at the specified offset.
note that a len of zero means lock to end of file
*/
-static int tdb_brlock(struct tdb_context *tdb,
- int rw_type, tdb_off_t offset, tdb_off_t len,
- enum tdb_lock_flags flags)
+static enum TDB_ERROR tdb_brlock(struct tdb_context *tdb,
+ int rw_type, tdb_off_t offset, tdb_off_t len,
+ enum tdb_lock_flags flags)
{
int ret;
if (tdb->flags & TDB_NOLOCK) {
- return 0;
+ return TDB_SUCCESS;
}
if (rw_type == F_WRLCK && tdb->read_only) {
- tdb->ecode = TDB_ERR_RDONLY;
- return -1;
+ return tdb_logerr(tdb, TDB_ERR_RDONLY, TDB_LOG_USE_ERROR,
+ "Write lock attempted on read-only database");
}
/* A 32 bit system cannot open a 64-bit file, but it could have
* expanded since then: check here. */
if ((size_t)(offset + len) != offset + len) {
- tdb->ecode = TDB_ERR_IO;
- tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
- "tdb_brlock: lock on giant offset %llu\n",
- (long long)(offset + len));
- return -1;
+ return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
+ "tdb_brlock: lock on giant offset %llu",
+ (long long)(offset + len));
}
do {
} while (ret == -1 && errno == EINTR);
if (ret == -1) {
- tdb->ecode = TDB_ERR_LOCK;
/* Generic lock error. errno set by fcntl.
* EAGAIN is an expected return from non-blocking
* locks. */
if (!(flags & TDB_LOCK_PROBE) && errno != EAGAIN) {
- tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
- "tdb_brlock failed (fd=%d) at"
- " offset %llu rw_type=%d flags=%d len=%llu\n",
- tdb->fd, (long long)offset, rw_type,
- flags, (long long)len);
+ tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
+ "tdb_brlock failed (fd=%d) at"
+ " offset %zu rw_type=%d flags=%d len=%zu:"
+ " %s",
+ tdb->file->fd, (size_t)offset, rw_type,
+ flags, (size_t)len, strerror(errno));
}
- return -1;
+ return TDB_ERR_LOCK;
}
- return 0;
+ return TDB_SUCCESS;
}
-static int tdb_brunlock(struct tdb_context *tdb,
- int rw_type, tdb_off_t offset, size_t len)
+static enum TDB_ERROR tdb_brunlock(struct tdb_context *tdb,
+ int rw_type, tdb_off_t offset, size_t len)
{
int ret;
if (tdb->flags & TDB_NOLOCK) {
- return 0;
+ return TDB_SUCCESS;
}
do {
ret = fcntl_unlock(tdb, rw_type, offset, len);
} while (ret == -1 && errno == EINTR);
- if (ret == -1) {
- tdb->log(tdb, TDB_DEBUG_TRACE, tdb->log_priv,
- "tdb_brunlock failed (fd=%d) at offset %llu"
- " rw_type=%d len=%llu\n",
- tdb->fd, (long long)offset, rw_type, (long long)len);
+ /* If we fail, *then* we verify that we owned the lock. If not, ok. */
+ if (ret == -1 && check_lock_pid(tdb, "tdb_brunlock", false)) {
+ return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
+ "tdb_brunlock failed (fd=%d) at offset %zu"
+ " rw_type=%d len=%zu",
+ tdb->file->fd, (size_t)offset, rw_type,
+ (size_t)len);
}
- return ret;
+ return TDB_SUCCESS;
}
-#if 0
/*
upgrade a read lock to a write lock. This needs to be handled in a
special way as some OSes (such as solaris) have too conservative
deadlock detection and claim a deadlock when progress can be
- made. For those OSes we may loop for a while.
+ made. For those OSes we may loop for a while.
*/
-int tdb_allrecord_upgrade(struct tdb_context *tdb)
+enum TDB_ERROR tdb_allrecord_upgrade(struct tdb_context *tdb)
{
int count = 1000;
- if (tdb->allrecord_lock.count != 1) {
- tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
- "tdb_allrecord_upgrade failed: count %u too high\n",
- tdb->allrecord_lock.count);
- return -1;
+ if (!check_lock_pid(tdb, "tdb_transaction_prepare_commit", true))
+ return TDB_ERR_LOCK;
+
+ if (tdb->file->allrecord_lock.count != 1) {
+ return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
+ "tdb_allrecord_upgrade failed:"
+ " count %u too high",
+ tdb->file->allrecord_lock.count);
+ }
+
+ if (tdb->file->allrecord_lock.off != 1) {
+ return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
+ "tdb_allrecord_upgrade failed:"
+ " already upgraded?");
}
- if (tdb->allrecord_lock.off != 1) {
- tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
- "tdb_allrecord_upgrade failed: already upgraded?\n");
- return -1;
+ if (tdb->file->allrecord_lock.owner != tdb) {
+ return owner_conflict(tdb, "tdb_allrecord_upgrade");
}
while (count--) {
struct timeval tv;
if (tdb_brlock(tdb, F_WRLCK,
- TDB_HASH_LOCK_START
- + (1ULL << tdb->header.v.hash_bits), 0,
- TDB_LOCK_WAIT|TDB_LOCK_PROBE) == 0) {
- tdb->allrecord_lock.ltype = F_WRLCK;
- tdb->allrecord_lock.off = 0;
- return 0;
+ TDB_HASH_LOCK_START, 0,
+ TDB_LOCK_WAIT|TDB_LOCK_PROBE) == TDB_SUCCESS) {
+ tdb->file->allrecord_lock.ltype = F_WRLCK;
+ tdb->file->allrecord_lock.off = 0;
+ return TDB_SUCCESS;
}
if (errno != EDEADLK) {
break;
tv.tv_usec = 1;
select(0, NULL, NULL, NULL, &tv);
}
- tdb->log(tdb, TDB_DEBUG_WARNING, tdb->log_priv,
- "tdb_allrecord_upgrade failed\n");
- return -1;
+ return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
+ "tdb_allrecord_upgrade failed");
}
-#endif
-static struct tdb_lock_type *find_nestlock(struct tdb_context *tdb,
- tdb_off_t offset)
+static struct tdb_lock *find_nestlock(struct tdb_context *tdb, tdb_off_t offset,
+ const struct tdb_context *owner)
{
unsigned int i;
- for (i=0; i<tdb->num_lockrecs; i++) {
- if (tdb->lockrecs[i].off == offset) {
- return &tdb->lockrecs[i];
+ for (i=0; i<tdb->file->num_lockrecs; i++) {
+ if (tdb->file->lockrecs[i].off == offset) {
+ if (owner && tdb->file->lockrecs[i].owner != owner)
+ return NULL;
+ return &tdb->file->lockrecs[i];
}
}
return NULL;
}
-/* lock an offset in the database. */
-static int tdb_nest_lock(struct tdb_context *tdb, tdb_off_t offset, int ltype,
- enum tdb_lock_flags flags)
+enum TDB_ERROR tdb_lock_and_recover(struct tdb_context *tdb)
{
- struct tdb_lock_type *new_lck;
-
- if (offset >= TDB_HASH_LOCK_START + TDB_HASH_LOCK_RANGE + tdb->map_size / 8) {
- tdb->ecode = TDB_ERR_LOCK;
- tdb->log(tdb, TDB_DEBUG_FATAL, tdb->log_priv,
- "tdb_lock: invalid offset %llu ltype=%d\n",
- (long long)offset, ltype);
- return -1;
- }
+ enum TDB_ERROR ecode;
- if (tdb->flags & TDB_NOLOCK)
- return 0;
+ if (!check_lock_pid(tdb, "tdb_transaction_prepare_commit", true))
+ return TDB_ERR_LOCK;
- new_lck = find_nestlock(tdb, offset);
- if (new_lck) {
- /*
- * Just increment the in-memory struct, posix locks
- * don't stack.
- */
- new_lck->count++;
- return 0;
+ ecode = tdb_allrecord_lock(tdb, F_WRLCK, TDB_LOCK_WAIT|TDB_LOCK_NOCHECK,
+ false);
+ if (ecode != TDB_SUCCESS) {
+ return ecode;
}
- new_lck = (struct tdb_lock_type *)realloc(
- tdb->lockrecs,
- sizeof(*tdb->lockrecs) * (tdb->num_lockrecs+1));
- if (new_lck == NULL) {
- tdb->ecode = TDB_ERR_OOM;
- tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
- "tdb_lock: unable to allocate %llu lock structure",
- (long long)(tdb->num_lockrecs + 1));
- errno = ENOMEM;
- return -1;
+ ecode = tdb_lock_open(tdb, TDB_LOCK_WAIT|TDB_LOCK_NOCHECK);
+ if (ecode != TDB_SUCCESS) {
+ tdb_allrecord_unlock(tdb, F_WRLCK);
+ return ecode;
}
- tdb->lockrecs = new_lck;
+ ecode = tdb_transaction_recover(tdb);
+ tdb_unlock_open(tdb);
+ tdb_allrecord_unlock(tdb, F_WRLCK);
- /* Since fcntl locks don't nest, we do a lock for the first one,
- and simply bump the count for future ones */
- if (tdb_brlock(tdb, ltype, offset, 1, flags)) {
- return -1;
+ return ecode;
+}
+
+/* lock an offset in the database. */
+static enum TDB_ERROR tdb_nest_lock(struct tdb_context *tdb,
+ tdb_off_t offset, int ltype,
+ enum tdb_lock_flags flags)
+{
+ struct tdb_lock *new_lck;
+ enum TDB_ERROR ecode;
+
+ if (offset > (TDB_HASH_LOCK_START + TDB_HASH_LOCK_RANGE
+ + tdb->file->map_size / 8)) {
+ return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
+ "tdb_nest_lock: invalid offset %zu ltype=%d",
+ (size_t)offset, ltype);
}
- tdb->lockrecs[tdb->num_lockrecs].off = offset;
- tdb->lockrecs[tdb->num_lockrecs].count = 1;
- tdb->lockrecs[tdb->num_lockrecs].ltype = ltype;
- tdb->num_lockrecs++;
+ if (tdb->flags & TDB_NOLOCK)
+ return TDB_SUCCESS;
- return 0;
-}
+ if (!check_lock_pid(tdb, "tdb_nest_lock", true)) {
+ return TDB_ERR_LOCK;
+ }
-static int tdb_lock_and_recover(struct tdb_context *tdb)
-{
-#if 0 /* FIXME */
+ add_stat(tdb, locks, 1);
- int ret;
+ new_lck = find_nestlock(tdb, offset, NULL);
+ if (new_lck) {
+ if (new_lck->owner != tdb) {
+ return owner_conflict(tdb, "tdb_nest_lock");
+ }
- /* We need to match locking order in transaction commit. */
- if (tdb_brlock(tdb, F_WRLCK, FREELIST_TOP, 0, TDB_LOCK_WAIT)) {
- return -1;
+ if (new_lck->ltype == F_RDLCK && ltype == F_WRLCK) {
+ return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
+ "tdb_nest_lock:"
+ " offset %zu has read lock",
+ (size_t)offset);
+ }
+ /* Just increment the struct, posix locks don't stack. */
+ new_lck->count++;
+ return TDB_SUCCESS;
}
- if (tdb_brlock(tdb, F_WRLCK, OPEN_LOCK, 1, TDB_LOCK_WAIT)) {
- tdb_brunlock(tdb, F_WRLCK, FREELIST_TOP, 0);
- return -1;
+ if (tdb->file->num_lockrecs
+ && offset >= TDB_HASH_LOCK_START
+ && offset < TDB_HASH_LOCK_START + TDB_HASH_LOCK_RANGE) {
+ return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
+ "tdb_nest_lock: already have a hash lock?");
}
- ret = tdb_transaction_recover(tdb);
+ new_lck = (struct tdb_lock *)realloc(
+ tdb->file->lockrecs,
+ sizeof(*tdb->file->lockrecs) * (tdb->file->num_lockrecs+1));
+ if (new_lck == NULL) {
+ return tdb_logerr(tdb, TDB_ERR_OOM, TDB_LOG_ERROR,
+ "tdb_nest_lock:"
+ " unable to allocate %zu lock struct",
+ tdb->file->num_lockrecs + 1);
+ }
+ tdb->file->lockrecs = new_lck;
- tdb_brunlock(tdb, F_WRLCK, OPEN_LOCK, 1);
- tdb_brunlock(tdb, F_WRLCK, FREELIST_TOP, 0);
+ /* Since fcntl locks don't nest, we do a lock for the first one,
+ and simply bump the count for future ones */
+ ecode = tdb_brlock(tdb, ltype, offset, 1, flags);
+ if (ecode != TDB_SUCCESS) {
+ return ecode;
+ }
+
+ /* First time we grab a lock, perhaps someone died in commit? */
+ if (!(flags & TDB_LOCK_NOCHECK)
+ && tdb->file->num_lockrecs == 0) {
+ tdb_bool_err berr = tdb_needs_recovery(tdb);
+ if (berr != false) {
+ tdb_brunlock(tdb, ltype, offset, 1);
+
+ if (berr < 0)
+ return berr;
+ ecode = tdb_lock_and_recover(tdb);
+ if (ecode == TDB_SUCCESS) {
+ ecode = tdb_brlock(tdb, ltype, offset, 1,
+ flags);
+ }
+ if (ecode != TDB_SUCCESS) {
+ return ecode;
+ }
+ }
+ }
- return ret;
-#else
- abort();
- return -1;
-#endif
-}
+ tdb->file->lockrecs[tdb->file->num_lockrecs].owner = tdb;
+ tdb->file->lockrecs[tdb->file->num_lockrecs].off = offset;
+ tdb->file->lockrecs[tdb->file->num_lockrecs].count = 1;
+ tdb->file->lockrecs[tdb->file->num_lockrecs].ltype = ltype;
+ tdb->file->num_lockrecs++;
-static bool tdb_needs_recovery(struct tdb_context *tdb)
-{
- /* FIXME */
- return false;
+ return TDB_SUCCESS;
}
-static int tdb_nest_unlock(struct tdb_context *tdb, tdb_off_t off, int ltype)
+static enum TDB_ERROR tdb_nest_unlock(struct tdb_context *tdb,
+ tdb_off_t off, int ltype)
{
- int ret = -1;
- struct tdb_lock_type *lck;
+ struct tdb_lock *lck;
+ enum TDB_ERROR ecode;
if (tdb->flags & TDB_NOLOCK)
- return 0;
+ return TDB_SUCCESS;
- lck = find_nestlock(tdb, off);
+ lck = find_nestlock(tdb, off, tdb);
if ((lck == NULL) || (lck->count == 0)) {
- tdb->ecode = TDB_ERR_LOCK;
- tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
- "tdb_unlock: no lock for %llu\n", (long long)off);
- return -1;
+ return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
+ "tdb_nest_unlock: no lock for %zu",
+ (size_t)off);
}
if (lck->count > 1) {
lck->count--;
- return 0;
+ return TDB_SUCCESS;
}
/*
* element, we're about to overwrite it with the last array element
* anyway.
*/
- ret = tdb_brunlock(tdb, ltype, off, 1);
+ ecode = tdb_brunlock(tdb, ltype, off, 1);
/*
* Shrink the array by overwriting the element just unlocked with the
* last array element.
*/
- *lck = tdb->lockrecs[--tdb->num_lockrecs];
+ *lck = tdb->file->lockrecs[--tdb->file->num_lockrecs];
- return ret;
+ return ecode;
}
-#if 0
/*
get the transaction lock
*/
-int tdb_transaction_lock(struct tdb_context *tdb, int ltype,
- enum tdb_lock_flags lockflags)
+enum TDB_ERROR tdb_transaction_lock(struct tdb_context *tdb, int ltype)
{
- return tdb_nest_lock(tdb, TRANSACTION_LOCK, ltype, lockflags);
+ return tdb_nest_lock(tdb, TDB_TRANSACTION_LOCK, ltype, TDB_LOCK_WAIT);
}
/*
release the transaction lock
*/
-int tdb_transaction_unlock(struct tdb_context *tdb, int ltype)
+void tdb_transaction_unlock(struct tdb_context *tdb, int ltype)
{
- return tdb_nest_unlock(tdb, TRANSACTION_LOCK, ltype, false);
+ tdb_nest_unlock(tdb, TDB_TRANSACTION_LOCK, ltype);
}
-#endif
/* We only need to lock individual bytes, but Linux merges consecutive locks
* so we lock in contiguous ranges. */
-static int tdb_lock_gradual(struct tdb_context *tdb,
- int ltype, enum tdb_lock_flags flags,
- tdb_off_t off, tdb_off_t len)
+static enum TDB_ERROR tdb_lock_gradual(struct tdb_context *tdb,
+ int ltype, enum tdb_lock_flags flags,
+ tdb_off_t off, tdb_off_t len)
{
- int ret;
+ enum TDB_ERROR ecode;
enum tdb_lock_flags nb_flags = (flags & ~TDB_LOCK_WAIT);
if (len <= 1) {
}
/* First we try non-blocking. */
- ret = tdb_brlock(tdb, ltype, off, len, nb_flags);
- if (ret == 0) {
- return 0;
+ if (tdb_brlock(tdb, ltype, off, len, nb_flags) == TDB_SUCCESS) {
+ return TDB_SUCCESS;
}
/* Try locking first half, then second. */
- ret = tdb_lock_gradual(tdb, ltype, flags, off, len / 2);
- if (ret == -1)
- return -1;
+ ecode = tdb_lock_gradual(tdb, ltype, flags, off, len / 2);
+ if (ecode != TDB_SUCCESS)
+ return ecode;
- ret = tdb_lock_gradual(tdb, ltype, flags,
- off + len / 2, len - len / 2);
- if (ret == -1) {
+ ecode = tdb_lock_gradual(tdb, ltype, flags,
+ off + len / 2, len - len / 2);
+ if (ecode != TDB_SUCCESS) {
tdb_brunlock(tdb, ltype, off, len / 2);
- return -1;
}
- return 0;
+ return ecode;
}
/* lock/unlock entire database. It can only be upgradable if you have some
- * other way of guaranteeing exclusivity (ie. transaction write lock).
- * Note that we don't lock the free chains: currently noone can get those locks
- * without a hash chain lock first. */
-int tdb_allrecord_lock(struct tdb_context *tdb, int ltype,
- enum tdb_lock_flags flags, bool upgradable)
-{
- /* FIXME: There are no locks on read-only dbs */
- if (tdb->read_only) {
- tdb->ecode = TDB_ERR_LOCK;
- tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
- "tdb_allrecord_lock: read-only\n");
- return -1;
- }
-
- if (tdb->allrecord_lock.count && tdb->allrecord_lock.ltype == ltype) {
- tdb->allrecord_lock.count++;
- return 0;
+ * other way of guaranteeing exclusivity (ie. transaction write lock). */
+enum TDB_ERROR tdb_allrecord_lock(struct tdb_context *tdb, int ltype,
+ enum tdb_lock_flags flags, bool upgradable)
+{
+ enum TDB_ERROR ecode;
+ tdb_bool_err berr;
+
+ if (tdb->flags & TDB_NOLOCK)
+ return TDB_SUCCESS;
+
+ if (!check_lock_pid(tdb, "tdb_allrecord_lock", true)) {
+ return TDB_ERR_LOCK;
}
- if (tdb->allrecord_lock.count) {
+ if (tdb->file->allrecord_lock.count) {
+ if (tdb->file->allrecord_lock.owner != tdb) {
+ return owner_conflict(tdb, "tdb_allrecord_lock");
+ }
+
+ if (ltype == F_RDLCK
+ || tdb->file->allrecord_lock.ltype == F_WRLCK) {
+ tdb->file->allrecord_lock.count++;
+ return TDB_SUCCESS;
+ }
+
/* a global lock of a different type exists */
- tdb->ecode = TDB_ERR_LOCK;
- tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
- "tdb_allrecord_lock: already have %s lock\n",
- tdb->allrecord_lock.ltype == F_RDLCK
- ? "read" : "write");
- return -1;
+ return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_USE_ERROR,
+ "tdb_allrecord_lock: already have %s lock",
+ tdb->file->allrecord_lock.ltype == F_RDLCK
+ ? "read" : "write");
}
- if (tdb_has_locks(tdb)) {
+ if (tdb_has_hash_locks(tdb)) {
/* can't combine global and chain locks */
- tdb->ecode = TDB_ERR_LOCK;
- tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
- "tdb_allrecord_lock: already have chain lock\n");
- return -1;
+ return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_USE_ERROR,
+ "tdb_allrecord_lock:"
+ " already have chain lock");
}
if (upgradable && ltype != F_RDLCK) {
/* tdb error: you can't upgrade a write lock! */
- tdb->ecode = TDB_ERR_LOCK;
- tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
- "tdb_allrecord_lock: can't upgrade a write lock\n");
- return -1;
+ return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
+ "tdb_allrecord_lock:"
+ " can't upgrade a write lock");
}
+ add_stat(tdb, locks, 1);
again:
- if (tdb_lock_gradual(tdb, ltype, flags, TDB_HASH_LOCK_START,
- TDB_HASH_LOCK_RANGE)) {
+ /* Lock hashes, gradually. */
+ ecode = tdb_lock_gradual(tdb, ltype, flags, TDB_HASH_LOCK_START,
+ TDB_HASH_LOCK_RANGE);
+ if (ecode != TDB_SUCCESS) {
+ if (!(flags & TDB_LOCK_PROBE)) {
+ tdb_logerr(tdb, ecode, TDB_LOG_ERROR,
+ "tdb_allrecord_lock hashes failed");
+ }
+ return ecode;
+ }
+
+ /* Lock free tables: there to end of file. */
+ ecode = tdb_brlock(tdb, ltype,
+ TDB_HASH_LOCK_START + TDB_HASH_LOCK_RANGE,
+ 0, flags);
+ if (ecode != TDB_SUCCESS) {
if (!(flags & TDB_LOCK_PROBE)) {
- tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
- "tdb_lockall hashes failed (%s)\n",
- strerror(errno));
+ tdb_logerr(tdb, ecode, TDB_LOG_ERROR,
+ "tdb_allrecord_lock freetables failed");
}
- return -1;
+ tdb_brunlock(tdb, ltype, TDB_HASH_LOCK_START,
+ TDB_HASH_LOCK_RANGE);
+ return ecode;
}
- tdb->allrecord_lock.count = 1;
+ tdb->file->allrecord_lock.owner = tdb;
+ tdb->file->allrecord_lock.count = 1;
/* If it's upgradable, it's actually exclusive so we can treat
* it as a write lock. */
- tdb->allrecord_lock.ltype = upgradable ? F_WRLCK : ltype;
- tdb->allrecord_lock.off = upgradable;
+ tdb->file->allrecord_lock.ltype = upgradable ? F_WRLCK : ltype;
+ tdb->file->allrecord_lock.off = upgradable;
/* Now check for needing recovery. */
- if (unlikely(tdb_needs_recovery(tdb))) {
- tdb_allrecord_unlock(tdb, ltype);
- if (tdb_lock_and_recover(tdb) == -1) {
- return -1;
- }
- goto again;
- }
+ if (flags & TDB_LOCK_NOCHECK)
+ return TDB_SUCCESS;
- return 0;
+ berr = tdb_needs_recovery(tdb);
+ if (likely(berr == false))
+ return TDB_SUCCESS;
+
+ tdb_allrecord_unlock(tdb, ltype);
+ if (berr < 0)
+ return berr;
+ ecode = tdb_lock_and_recover(tdb);
+ if (ecode != TDB_SUCCESS) {
+ return ecode;
+ }
+ goto again;
}
-int tdb_lock_open(struct tdb_context *tdb)
+enum TDB_ERROR tdb_lock_open(struct tdb_context *tdb, enum tdb_lock_flags flags)
{
- return tdb_nest_lock(tdb, TDB_OPEN_LOCK, F_WRLCK, TDB_LOCK_WAIT);
+ return tdb_nest_lock(tdb, TDB_OPEN_LOCK, F_WRLCK, flags);
}
void tdb_unlock_open(struct tdb_context *tdb)
tdb_nest_unlock(tdb, TDB_OPEN_LOCK, F_WRLCK);
}
-int tdb_lock_expand(struct tdb_context *tdb, int ltype)
+bool tdb_has_open_lock(struct tdb_context *tdb)
{
- return tdb_nest_lock(tdb, TDB_EXPANSION_LOCK, ltype, TDB_LOCK_WAIT);
+ return !(tdb->flags & TDB_NOLOCK)
+ && find_nestlock(tdb, TDB_OPEN_LOCK, tdb) != NULL;
+}
+
+enum TDB_ERROR tdb_lock_expand(struct tdb_context *tdb, int ltype)
+{
+ /* Lock doesn't protect data, so don't check (we recurse if we do!) */
+ return tdb_nest_lock(tdb, TDB_EXPANSION_LOCK, ltype,
+ TDB_LOCK_WAIT | TDB_LOCK_NOCHECK);
}
void tdb_unlock_expand(struct tdb_context *tdb, int ltype)
}
/* unlock entire db */
-int tdb_allrecord_unlock(struct tdb_context *tdb, int ltype)
+void tdb_allrecord_unlock(struct tdb_context *tdb, int ltype)
{
- /* FIXME: There are no locks on read-only dbs */
- if (tdb->read_only) {
- tdb->ecode = TDB_ERR_LOCK;
- tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
- "tdb_allrecord_unlock: read-only\n");
- return -1;
+ if (tdb->flags & TDB_NOLOCK)
+ return;
+
+ if (tdb->file->allrecord_lock.count == 0) {
+ tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_USE_ERROR,
+ "tdb_allrecord_unlock: not locked!");
+ return;
}
- if (tdb->allrecord_lock.count == 0) {
- tdb->ecode = TDB_ERR_LOCK;
- tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
- "tdb_allrecord_unlock: not locked!\n");
- return -1;
+ if (tdb->file->allrecord_lock.owner != tdb) {
+ tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_USE_ERROR,
+ "tdb_allrecord_unlock: not locked by us!");
+ return;
}
/* Upgradable locks are marked as write locks. */
- if (tdb->allrecord_lock.ltype != ltype
- && (!tdb->allrecord_lock.off || ltype != F_RDLCK)) {
- tdb->ecode = TDB_ERR_LOCK;
- tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
- "tdb_allrecord_unlock: have %s lock\n",
- tdb->allrecord_lock.ltype == F_RDLCK
- ? "read" : "write");
- return -1;
- }
-
- if (tdb->allrecord_lock.count > 1) {
- tdb->allrecord_lock.count--;
- return 0;
+ if (tdb->file->allrecord_lock.ltype != ltype
+ && (!tdb->file->allrecord_lock.off || ltype != F_RDLCK)) {
+ tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
+ "tdb_allrecord_unlock: have %s lock",
+ tdb->file->allrecord_lock.ltype == F_RDLCK
+ ? "read" : "write");
+ return;
}
- tdb->allrecord_lock.count = 0;
- tdb->allrecord_lock.ltype = 0;
-
- return tdb_brunlock(tdb, ltype, TDB_HASH_LOCK_START,
- TDB_HASH_LOCK_RANGE);
-}
+ if (tdb->file->allrecord_lock.count > 1) {
+ tdb->file->allrecord_lock.count--;
+ return;
+ }
-bool tdb_has_expansion_lock(struct tdb_context *tdb)
-{
- return find_nestlock(tdb, TDB_EXPANSION_LOCK) != NULL
- || (tdb->flags & TDB_NOLOCK);
-}
+ tdb->file->allrecord_lock.count = 0;
+ tdb->file->allrecord_lock.ltype = 0;
-bool tdb_has_locks(struct tdb_context *tdb)
-{
- return tdb->allrecord_lock.count || tdb->num_lockrecs;
+ tdb_brunlock(tdb, ltype, TDB_HASH_LOCK_START, 0);
}
-#if 0
-/* lock entire database with write lock */
-int tdb_lockall(struct tdb_context *tdb)
+bool tdb_has_expansion_lock(struct tdb_context *tdb)
{
- tdb_trace(tdb, "tdb_lockall");
- return tdb_allrecord_lock(tdb, F_WRLCK, TDB_LOCK_WAIT, false);
+ return find_nestlock(tdb, TDB_EXPANSION_LOCK, tdb) != NULL;
}
-/* lock entire database with write lock - nonblocking varient */
-int tdb_lockall_nonblock(struct tdb_context *tdb)
+bool tdb_has_hash_locks(struct tdb_context *tdb)
{
- int ret = tdb_allrecord_lock(tdb, F_WRLCK, TDB_LOCK_NOWAIT, false);
- tdb_trace_ret(tdb, "tdb_lockall_nonblock", ret);
- return ret;
-}
+ unsigned int i;
-/* unlock entire database with write lock */
-int tdb_unlockall(struct tdb_context *tdb)
-{
- tdb_trace(tdb, "tdb_unlockall");
- return tdb_allrecord_unlock(tdb, F_WRLCK);
+ for (i=0; i<tdb->file->num_lockrecs; i++) {
+ if (tdb->file->lockrecs[i].off >= TDB_HASH_LOCK_START
+ && tdb->file->lockrecs[i].off < (TDB_HASH_LOCK_START
+ + TDB_HASH_LOCK_RANGE))
+ return true;
+ }
+ return false;
}
-/* lock entire database with read lock */
-int tdb_lockall_read(struct tdb_context *tdb)
+static bool tdb_has_free_lock(struct tdb_context *tdb)
{
- tdb_trace(tdb, "tdb_lockall_read");
- return tdb_allrecord_lock(tdb, F_RDLCK, TDB_LOCK_WAIT, false);
-}
+ unsigned int i;
-/* lock entire database with read lock - nonblock varient */
-int tdb_lockall_read_nonblock(struct tdb_context *tdb)
-{
- int ret = tdb_allrecord_lock(tdb, F_RDLCK, TDB_LOCK_NOWAIT, false);
- tdb_trace_ret(tdb, "tdb_lockall_read_nonblock", ret);
- return ret;
-}
+ if (tdb->flags & TDB_NOLOCK)
+ return false;
-/* unlock entire database with read lock */
-int tdb_unlockall_read(struct tdb_context *tdb)
-{
- tdb_trace(tdb, "tdb_unlockall_read");
- return tdb_allrecord_unlock(tdb, F_RDLCK);
+ for (i=0; i<tdb->file->num_lockrecs; i++) {
+ if (tdb->file->lockrecs[i].off
+ > TDB_HASH_LOCK_START + TDB_HASH_LOCK_RANGE)
+ return true;
+ }
+ return false;
}
-#endif
-int tdb_lock_hashes(struct tdb_context *tdb,
- tdb_off_t hash_lock,
- tdb_len_t hash_range,
- int ltype, enum tdb_lock_flags waitflag)
+enum TDB_ERROR tdb_lock_hashes(struct tdb_context *tdb,
+ tdb_off_t hash_lock,
+ tdb_len_t hash_range,
+ int ltype, enum tdb_lock_flags waitflag)
{
/* FIXME: Do this properly, using hlock_range */
unsigned lock = TDB_HASH_LOCK_START
+ (hash_lock >> (64 - TDB_HASH_LOCK_RANGE_BITS));
/* a allrecord lock allows us to avoid per chain locks */
- if (tdb->allrecord_lock.count &&
- (ltype == tdb->allrecord_lock.ltype || ltype == F_RDLCK)) {
- return 0;
+ if (tdb->file->allrecord_lock.count) {
+ if (!check_lock_pid(tdb, "tdb_lock_hashes", true))
+ return TDB_ERR_LOCK;
+
+ if (tdb->file->allrecord_lock.owner != tdb)
+ return owner_conflict(tdb, "tdb_lock_hashes");
+ if (ltype == tdb->file->allrecord_lock.ltype
+ || ltype == F_RDLCK) {
+ return TDB_SUCCESS;
+ }
+
+ return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_USE_ERROR,
+ "tdb_lock_hashes:"
+ " already have %s allrecordlock",
+ tdb->file->allrecord_lock.ltype == F_RDLCK
+ ? "read" : "write");
+ }
+
+ if (tdb_has_free_lock(tdb)) {
+ return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
+ "tdb_lock_hashes: already have free lock");
}
- if (tdb->allrecord_lock.count) {
- tdb->ecode = TDB_ERR_LOCK;
- tdb->log(tdb, TDB_DEBUG_ERROR, tdb->log_priv,
- "tdb_lock_list: have %s allrecordlock\n",
- tdb->allrecord_lock.ltype == F_RDLCK
- ? "read" : "write");
- return -1;
+ if (tdb_has_expansion_lock(tdb)) {
+ return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
+ "tdb_lock_hashes:"
+ " already have expansion lock");
}
return tdb_nest_lock(tdb, lock, ltype, waitflag);
}
-int tdb_unlock_hashes(struct tdb_context *tdb,
- tdb_off_t hash_lock,
- tdb_len_t hash_range, int ltype)
+enum TDB_ERROR tdb_unlock_hashes(struct tdb_context *tdb,
+ tdb_off_t hash_lock,
+ tdb_len_t hash_range, int ltype)
{
unsigned lock = TDB_HASH_LOCK_START
+ (hash_lock >> (64 - TDB_HASH_LOCK_RANGE_BITS));
+ if (tdb->flags & TDB_NOLOCK)
+ return 0;
+
/* a allrecord lock allows us to avoid per chain locks */
- if (tdb->allrecord_lock.count) {
- if (tdb->allrecord_lock.ltype == F_RDLCK
+ if (tdb->file->allrecord_lock.count) {
+ if (tdb->file->allrecord_lock.ltype == F_RDLCK
&& ltype == F_WRLCK) {
- tdb->ecode = TDB_ERR_LOCK;
- tdb->log(tdb, TDB_DEBUG_FATAL, tdb->log_priv,
- "tdb_unlock_list RO allrecord!\n");
- return -1;
+ return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
+ "tdb_unlock_hashes RO allrecord!");
}
- return 0;
+ return TDB_SUCCESS;
}
return tdb_nest_unlock(tdb, lock, ltype);
*/
static tdb_off_t free_lock_off(tdb_off_t b_off)
{
- return TDB_HASH_LOCK_START + TDB_HASH_LOCK_RANGE + b_off / sizeof(tdb_off_t);
+ return TDB_HASH_LOCK_START + TDB_HASH_LOCK_RANGE
+ + b_off / sizeof(tdb_off_t);
}
-int tdb_lock_free_bucket(struct tdb_context *tdb, tdb_off_t b_off,
- enum tdb_lock_flags waitflag)
+enum TDB_ERROR tdb_lock_free_bucket(struct tdb_context *tdb, tdb_off_t b_off,
+ enum tdb_lock_flags waitflag)
{
assert(b_off >= sizeof(struct tdb_header));
- /* You're supposed to have a hash lock first! */
- if (!(tdb->flags & TDB_NOLOCK) && !tdb_has_locks(tdb)) {
- tdb->ecode = TDB_ERR_LOCK;
- tdb->log(tdb, TDB_DEBUG_FATAL, tdb->log_priv,
- "tdb_lock_free_list without lock!\n");
- return -1;
- }
+ if (tdb->flags & TDB_NOLOCK)
+ return 0;
/* a allrecord lock allows us to avoid per chain locks */
- if (tdb->allrecord_lock.count) {
- if (tdb->allrecord_lock.ltype == F_WRLCK)
+ if (tdb->file->allrecord_lock.count) {
+ if (!check_lock_pid(tdb, "tdb_lock_free_bucket", true))
+ return TDB_ERR_LOCK;
+
+ if (tdb->file->allrecord_lock.ltype == F_WRLCK)
return 0;
- tdb->ecode = TDB_ERR_LOCK;
- tdb->log(tdb, TDB_DEBUG_FATAL, tdb->log_priv,
- "tdb_lock_free_list with RO allrecordlock!\n");
- return -1;
+ return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
+ "tdb_lock_free_bucket with"
+ " read-only allrecordlock!");
}
+#if 0 /* FIXME */
+ if (tdb_has_expansion_lock(tdb)) {
+ return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
+ "tdb_lock_free_bucket:"
+ " already have expansion lock");
+ }
+#endif
+
return tdb_nest_lock(tdb, free_lock_off(b_off), F_WRLCK, waitflag);
}
void tdb_unlock_free_bucket(struct tdb_context *tdb, tdb_off_t b_off)
{
- if (tdb->allrecord_lock.count)
+ if (tdb->file->allrecord_lock.count)
return;
tdb_nest_unlock(tdb, free_lock_off(b_off), F_WRLCK);
}
-/* Even if the entry isn't in this hash bucket, you'd have to lock this
- * bucket to find it. */
-static int chainlock(struct tdb_context *tdb, const TDB_DATA *key,
- int ltype, enum tdb_lock_flags waitflag,
- const char *func)
-{
- int ret;
- uint64_t h = tdb_hash(tdb, key->dptr, key->dsize);
-
- ret = tdb_lock_hashes(tdb, h, 1, ltype, waitflag);
- tdb_trace_1rec(tdb, func, *key);
- return ret;
-}
-
-/* lock/unlock one hash chain. This is meant to be used to reduce
- contention - it cannot guarantee how many records will be locked */
-int tdb_chainlock(struct tdb_context *tdb, TDB_DATA key)
-{
- return chainlock(tdb, &key, F_WRLCK, TDB_LOCK_WAIT, "tdb_chainlock");
-}
-
-int tdb_chainunlock(struct tdb_context *tdb, TDB_DATA key)
-{
- uint64_t h = tdb_hash(tdb, key.dptr, key.dsize);
- tdb_trace_1rec(tdb, "tdb_chainunlock", key);
- return tdb_unlock_hashes(tdb, h, 1, F_WRLCK);
-}
-
-#if 0
-/* lock/unlock one hash chain, non-blocking. This is meant to be used
- to reduce contention - it cannot guarantee how many records will be
- locked */
-int tdb_chainlock_nonblock(struct tdb_context *tdb, TDB_DATA key)
-{
- return chainlock(tdb, &key, F_WRLCK, TDB_LOCK_NOWAIT,
- "tdb_chainlock_nonblock");
-}
-
-int tdb_chainlock_read(struct tdb_context *tdb, TDB_DATA key)
+enum TDB_ERROR tdb_lockall(struct tdb_context *tdb)
{
- return chainlock(tdb, &key, F_RDLCK, TDB_LOCK_WAIT,
- "tdb_chainlock_read");
-}
-
-int tdb_chainunlock_read(struct tdb_context *tdb, TDB_DATA key)
-{
- uint64_t h = tdb_hash(tdb, key.dptr, key.dsize);
- tdb_trace_1rec(tdb, "tdb_chainunlock_read", key);
- return tdb_unlock_list(tdb, h & ((1ULL << tdb->header.v.hash_bits)-1),
- F_RDLCK);
+ return tdb_allrecord_lock(tdb, F_WRLCK, TDB_LOCK_WAIT, false);
}
-/* record lock stops delete underneath */
-int tdb_lock_record(struct tdb_context *tdb, tdb_off_t off)
+void tdb_unlockall(struct tdb_context *tdb)
{
- if (tdb->allrecord_lock.count) {
- return 0;
- }
- return off ? tdb_brlock(tdb, F_RDLCK, off, 1, TDB_LOCK_WAIT) : 0;
-}
-
-/*
- Write locks override our own fcntl readlocks, so check it here.
- Note this is meant to be F_SETLK, *not* F_SETLKW, as it's not
- an error to fail to get the lock here.
-*/
-int tdb_write_lock_record(struct tdb_context *tdb, tdb_off_t off)
-{
- struct tdb_traverse_lock *i;
- for (i = &tdb->travlocks; i; i = i->next)
- if (i->off == off)
- return -1;
- if (tdb->allrecord_lock.count) {
- if (tdb->allrecord_lock.ltype == F_WRLCK) {
- return 0;
- }
- return -1;
- }
- return tdb_brlock(tdb, F_WRLCK, off, 1, TDB_LOCK_NOWAIT|TDB_LOCK_PROBE);
+ tdb_allrecord_unlock(tdb, F_WRLCK);
}
-int tdb_write_unlock_record(struct tdb_context *tdb, tdb_off_t off)
+enum TDB_ERROR tdb_lockall_read(struct tdb_context *tdb)
{
- if (tdb->allrecord_lock.count) {
- return 0;
- }
- return tdb_brunlock(tdb, F_WRLCK, off, 1);
+ return tdb_allrecord_lock(tdb, F_RDLCK, TDB_LOCK_WAIT, false);
}
-/* fcntl locks don't stack: avoid unlocking someone else's */
-int tdb_unlock_record(struct tdb_context *tdb, tdb_off_t off)
+void tdb_unlockall_read(struct tdb_context *tdb)
{
- struct tdb_traverse_lock *i;
- uint32_t count = 0;
-
- if (tdb->allrecord_lock.count) {
- return 0;
- }
-
- if (off == 0)
- return 0;
- for (i = &tdb->travlocks; i; i = i->next)
- if (i->off == off)
- count++;
- return (count == 1 ? tdb_brunlock(tdb, F_RDLCK, off, 1) : 0);
+ tdb_allrecord_unlock(tdb, F_RDLCK);
}
-/* The transaction code uses this to remove all locks. */
-void tdb_release_transaction_locks(struct tdb_context *tdb)
+void tdb_lock_cleanup(struct tdb_context *tdb)
{
unsigned int i;
- if (tdb->allrecord_lock.count != 0) {
- tdb_off_t hash_size, free_size;
-
- hash_size = (1ULL << tdb->header.v.hash_bits)
- * sizeof(tdb_off_t);
- free_size = tdb->header.v.free_zones
- * (tdb->header.v.free_buckets + 1) * sizeof(tdb_off_t);
-
- tdb_brunlock(tdb, tdb->allrecord_lock.ltype,
- tdb->header.v.hash_off, hash_size);
- tdb_brunlock(tdb, tdb->allrecord_lock.ltype,
- tdb->header.v.free_off, free_size);
- tdb->allrecord_lock.count = 0;
- tdb->allrecord_lock.ltype = 0;
+ while (tdb->file->allrecord_lock.count
+ && tdb->file->allrecord_lock.owner == tdb) {
+ tdb_allrecord_unlock(tdb, tdb->file->allrecord_lock.ltype);
}
- for (i = 0; i<tdb->num_lockrecs; i++) {
- struct tdb_lock_type *lck = &tdb->lockrecs[i];
-
- tdb_brunlock(tdb, lck->ltype, lck->off, 1);
+ for (i=0; i<tdb->file->num_lockrecs; i++) {
+ if (tdb->file->lockrecs[i].owner == tdb) {
+ tdb_nest_unlock(tdb,
+ tdb->file->lockrecs[i].off,
+ tdb->file->lockrecs[i].ltype);
+ i--;
+ }
}
- tdb->num_lockrecs = 0;
- SAFE_FREE(tdb->lockrecs);
- tdb->header_uptodate = false;
-}
-#endif
-
-void tdb_lock_init(struct tdb_context *tdb)
-{
- tdb->num_lockrecs = 0;
- tdb->lockrecs = NULL;
- tdb->allrecord_lock.count = 0;
}