continue; \
}
-typedef struct dbuf_hold_arg {
- /* Function arguments */
- dnode_t *dh_dn;
- uint8_t dh_level;
- uint64_t dh_blkid;
- boolean_t dh_fail_sparse;
- boolean_t dh_fail_uncached;
- void *dh_tag;
- dmu_buf_impl_t **dh_dbp;
- /* Local variables */
- dmu_buf_impl_t *dh_db;
- dmu_buf_impl_t *dh_parent;
- blkptr_t *dh_bp;
- int dh_err;
- dbuf_dirty_record_t *dh_dr;
-} dbuf_hold_arg_t;
-
-static dbuf_hold_arg_t *dbuf_hold_arg_create(dnode_t *dn, uint8_t level,
- uint64_t blkid, boolean_t fail_sparse, boolean_t fail_uncached,
- void *tag, dmu_buf_impl_t **dbp);
-static int dbuf_hold_impl_arg(dbuf_hold_arg_t *dh);
-static void dbuf_hold_arg_destroy(dbuf_hold_arg_t *dh);
-
static boolean_t dbuf_undirty(dmu_buf_impl_t *db, dmu_tx_t *tx);
static void dbuf_write(dbuf_dirty_record_t *dr, arc_buf_t *data, dmu_tx_t *tx);
} else if (level < nlevels-1) {
/* this block is referenced from an indirect block */
int err;
- dbuf_hold_arg_t *dh = dbuf_hold_arg_create(dn, level + 1,
+
+ err = dbuf_hold_impl(dn, level + 1,
blkid >> epbs, fail_sparse, FALSE, NULL, parentp);
- err = dbuf_hold_impl_arg(dh);
- dbuf_hold_arg_destroy(dh);
+
if (err)
return (err);
err = dbuf_read(*parentp, NULL,
zio_nowait(pio);
}
-#define DBUF_HOLD_IMPL_MAX_DEPTH 20
-
/*
- * Helper function for dbuf_hold_impl_arg() to copy a buffer. Handles
+ * Helper function for dbuf_hold_impl() to copy a buffer. Handles
* the case of encrypted, compressed and uncompressed buffers by
* allocating the new buffer, respectively, with arc_alloc_raw_buf(),
* arc_alloc_compressed_buf() or arc_alloc_buf().*
*
- * NOTE: Declared noinline to avoid stack bloat in dbuf_hold_impl_arg().
+ * NOTE: Declared noinline to avoid stack bloat in dbuf_hold_impl().
*/
noinline static void
-dbuf_hold_copy(struct dbuf_hold_arg *dh)
+dbuf_hold_copy(dnode_t *dn, dmu_buf_impl_t *db)
{
- dnode_t *dn = dh->dh_dn;
- dmu_buf_impl_t *db = dh->dh_db;
- dbuf_dirty_record_t *dr = dh->dh_dr;
+ dbuf_dirty_record_t *dr = db->db_data_pending;
arc_buf_t *data = dr->dt.dl.dr_data;
-
enum zio_compress compress_type = arc_get_compression(data);
if (arc_is_encrypted(data)) {
* Returns with db_holds incremented, and db_mtx not held.
* Note: dn_struct_rwlock must be held.
*/
-static int
-dbuf_hold_impl_arg(struct dbuf_hold_arg *dh)
+int
+dbuf_hold_impl(dnode_t *dn, uint8_t level, uint64_t blkid,
+ boolean_t fail_sparse, boolean_t fail_uncached,
+ void *tag, dmu_buf_impl_t **dbp)
{
- dh->dh_parent = NULL;
-
- ASSERT(dh->dh_blkid != DMU_BONUS_BLKID);
- ASSERT(RW_LOCK_HELD(&dh->dh_dn->dn_struct_rwlock));
- ASSERT3U(dh->dh_dn->dn_nlevels, >, dh->dh_level);
-
- *(dh->dh_dbp) = NULL;
+ dmu_buf_impl_t *db, *parent = NULL;
/* If the pool has been created, verify the tx_sync_lock is not held */
- spa_t *spa = dh->dh_dn->dn_objset->os_spa;
+ spa_t *spa = dn->dn_objset->os_spa;
dsl_pool_t *dp = spa->spa_dsl_pool;
if (dp != NULL) {
ASSERT(!MUTEX_HELD(&dp->dp_tx.tx_sync_lock));
}
+ ASSERT(blkid != DMU_BONUS_BLKID);
+ ASSERT(RW_LOCK_HELD(&dn->dn_struct_rwlock));
+ ASSERT3U(dn->dn_nlevels, >, level);
+
+ *dbp = NULL;
+
/* dbuf_find() returns with db_mtx held */
- dh->dh_db = dbuf_find(dh->dh_dn->dn_objset, dh->dh_dn->dn_object,
- dh->dh_level, dh->dh_blkid);
+ db = dbuf_find(dn->dn_objset, dn->dn_object, level, blkid);
- if (dh->dh_db == NULL) {
- dh->dh_bp = NULL;
+ if (db == NULL) {
+ blkptr_t *bp = NULL;
+ int err;
- if (dh->dh_fail_uncached)
+ if (fail_uncached)
return (SET_ERROR(ENOENT));
- ASSERT3P(dh->dh_parent, ==, NULL);
- dh->dh_err = dbuf_findbp(dh->dh_dn, dh->dh_level, dh->dh_blkid,
- dh->dh_fail_sparse, &dh->dh_parent, &dh->dh_bp);
- if (dh->dh_fail_sparse) {
- if (dh->dh_err == 0 &&
- dh->dh_bp && BP_IS_HOLE(dh->dh_bp))
- dh->dh_err = SET_ERROR(ENOENT);
- if (dh->dh_err) {
- if (dh->dh_parent)
- dbuf_rele(dh->dh_parent, NULL);
- return (dh->dh_err);
+ ASSERT3P(parent, ==, NULL);
+ err = dbuf_findbp(dn, level, blkid, fail_sparse, &parent, &bp);
+ if (fail_sparse) {
+ if (err == 0 && bp && BP_IS_HOLE(bp))
+ err = SET_ERROR(ENOENT);
+ if (err) {
+ if (parent)
+ dbuf_rele(parent, NULL);
+ return (err);
}
}
- if (dh->dh_err && dh->dh_err != ENOENT)
- return (dh->dh_err);
- dh->dh_db = dbuf_create(dh->dh_dn, dh->dh_level, dh->dh_blkid,
- dh->dh_parent, dh->dh_bp);
+ if (err && err != ENOENT)
+ return (err);
+ db = dbuf_create(dn, level, blkid, parent, bp);
}
- if (dh->dh_fail_uncached && dh->dh_db->db_state != DB_CACHED) {
- mutex_exit(&dh->dh_db->db_mtx);
+ if (fail_uncached && db->db_state != DB_CACHED) {
+ mutex_exit(&db->db_mtx);
return (SET_ERROR(ENOENT));
}
- if (dh->dh_db->db_buf != NULL) {
- arc_buf_access(dh->dh_db->db_buf);
- ASSERT3P(dh->dh_db->db.db_data, ==, dh->dh_db->db_buf->b_data);
+ if (db->db_buf != NULL) {
+ arc_buf_access(db->db_buf);
+ ASSERT3P(db->db.db_data, ==, db->db_buf->b_data);
}
- ASSERT(dh->dh_db->db_buf == NULL || arc_referenced(dh->dh_db->db_buf));
+ ASSERT(db->db_buf == NULL || arc_referenced(db->db_buf));
/*
* If this buffer is currently syncing out, and we are
* still referencing it from db_data, we need to make a copy
* of it in case we decide we want to dirty it again in this txg.
*/
- if (dh->dh_db->db_level == 0 &&
- dh->dh_db->db_blkid != DMU_BONUS_BLKID &&
- dh->dh_dn->dn_object != DMU_META_DNODE_OBJECT &&
- dh->dh_db->db_state == DB_CACHED && dh->dh_db->db_data_pending) {
- dh->dh_dr = dh->dh_db->db_data_pending;
- if (dh->dh_dr->dt.dl.dr_data == dh->dh_db->db_buf)
- dbuf_hold_copy(dh);
+ if (db->db_level == 0 && db->db_blkid != DMU_BONUS_BLKID &&
+ dn->dn_object != DMU_META_DNODE_OBJECT &&
+ db->db_state == DB_CACHED && db->db_data_pending) {
+ dbuf_dirty_record_t *dr = db->db_data_pending;
+ if (dr->dt.dl.dr_data == db->db_buf)
+ dbuf_hold_copy(dn, db);
}
- if (multilist_link_active(&dh->dh_db->db_cache_link)) {
- ASSERT(zfs_refcount_is_zero(&dh->dh_db->db_holds));
- ASSERT(dh->dh_db->db_caching_status == DB_DBUF_CACHE ||
- dh->dh_db->db_caching_status == DB_DBUF_METADATA_CACHE);
+ if (multilist_link_active(&db->db_cache_link)) {
+ ASSERT(zfs_refcount_is_zero(&db->db_holds));
+ ASSERT(db->db_caching_status == DB_DBUF_CACHE ||
+ db->db_caching_status == DB_DBUF_METADATA_CACHE);
- multilist_remove(
- dbuf_caches[dh->dh_db->db_caching_status].cache,
- dh->dh_db);
+ multilist_remove(dbuf_caches[db->db_caching_status].cache, db);
(void) zfs_refcount_remove_many(
- &dbuf_caches[dh->dh_db->db_caching_status].size,
- dh->dh_db->db.db_size, dh->dh_db);
+ &dbuf_caches[db->db_caching_status].size,
+ db->db.db_size, db);
- if (dh->dh_db->db_caching_status == DB_DBUF_METADATA_CACHE) {
+ if (db->db_caching_status == DB_DBUF_METADATA_CACHE) {
DBUF_STAT_BUMPDOWN(metadata_cache_count);
} else {
- DBUF_STAT_BUMPDOWN(cache_levels[dh->dh_db->db_level]);
+ DBUF_STAT_BUMPDOWN(cache_levels[db->db_level]);
DBUF_STAT_BUMPDOWN(cache_count);
- DBUF_STAT_DECR(cache_levels_bytes[dh->dh_db->db_level],
- dh->dh_db->db.db_size);
+ DBUF_STAT_DECR(cache_levels_bytes[db->db_level],
+ db->db.db_size);
}
- dh->dh_db->db_caching_status = DB_NO_CACHE;
+ db->db_caching_status = DB_NO_CACHE;
}
- (void) zfs_refcount_add(&dh->dh_db->db_holds, dh->dh_tag);
- DBUF_VERIFY(dh->dh_db);
- mutex_exit(&dh->dh_db->db_mtx);
+ (void) zfs_refcount_add(&db->db_holds, tag);
+ DBUF_VERIFY(db);
+ mutex_exit(&db->db_mtx);
/* NOTE: we can't rele the parent until after we drop the db_mtx */
- if (dh->dh_parent)
- dbuf_rele(dh->dh_parent, NULL);
+ if (parent)
+ dbuf_rele(parent, NULL);
- ASSERT3P(DB_DNODE(dh->dh_db), ==, dh->dh_dn);
- ASSERT3U(dh->dh_db->db_blkid, ==, dh->dh_blkid);
- ASSERT3U(dh->dh_db->db_level, ==, dh->dh_level);
- *(dh->dh_dbp) = dh->dh_db;
+ ASSERT3P(DB_DNODE(db), ==, dn);
+ ASSERT3U(db->db_blkid, ==, blkid);
+ ASSERT3U(db->db_level, ==, level);
+ *dbp = db;
return (0);
}
-/*
- * dbuf_hold_impl_arg() is called recursively, via dbuf_findbp(). There can
- * be as many recursive calls as there are levels of on-disk indirect blocks,
- * but typically only 0-2 recursive calls. To minimize the stack frame size,
- * the recursive function's arguments and "local variables" are allocated on
- * the heap as the dbuf_hold_arg_t.
- */
-int
-dbuf_hold_impl(dnode_t *dn, uint8_t level, uint64_t blkid,
- boolean_t fail_sparse, boolean_t fail_uncached,
- void *tag, dmu_buf_impl_t **dbp)
-{
- dbuf_hold_arg_t *dh = dbuf_hold_arg_create(dn, level, blkid,
- fail_sparse, fail_uncached, tag, dbp);
-
- int error = dbuf_hold_impl_arg(dh);
-
- dbuf_hold_arg_destroy(dh);
-
- return (error);
-}
-
-static dbuf_hold_arg_t *
-dbuf_hold_arg_create(dnode_t *dn, uint8_t level, uint64_t blkid,
- boolean_t fail_sparse, boolean_t fail_uncached,
- void *tag, dmu_buf_impl_t **dbp)
-{
- dbuf_hold_arg_t *dh = kmem_alloc(sizeof (*dh), KM_SLEEP);
- dh->dh_dn = dn;
- dh->dh_level = level;
- dh->dh_blkid = blkid;
-
- dh->dh_fail_sparse = fail_sparse;
- dh->dh_fail_uncached = fail_uncached;
-
- dh->dh_tag = tag;
- dh->dh_dbp = dbp;
-
- dh->dh_db = NULL;
- dh->dh_parent = NULL;
- dh->dh_bp = NULL;
- dh->dh_err = 0;
- dh->dh_dr = NULL;
-
- return (dh);
-}
-
-static void
-dbuf_hold_arg_destroy(dbuf_hold_arg_t *dh)
-{
- kmem_free(dh, sizeof (*dh));
-}
-
dmu_buf_impl_t *
dbuf_hold(dnode_t *dn, uint64_t blkid, void *tag)
{