File incorrectly zeroed when receiving incremental stream that toggles -L

cmd/zhack/zhack.c

@@ -103,8 +103,8 @@ fatal(spa_t *spa, void *tag, const char *fmt, ...)
 
 /* ARGSUSED */
 static int
-space_delta_cb(dmu_object_type_t bonustype, void *data,
-    uint64_t *userp, uint64_t *groupp, uint64_t *projectp)
+space_delta_cb(dmu_object_type_t bonustype, const void *data,
+    zfs_file_info_t *zoi)
 {
 	/*
 	 * Is it a valid type of object to track?

include/sys/dmu.h

@@ -1013,10 +1013,17 @@ extern int dmu_snapshot_realname(objset_t *os, char *name, char *real,
 extern int dmu_dir_list_next(objset_t *os, int namelen, char *name,
     uint64_t *idp, uint64_t *offp);
 
-typedef int objset_used_cb_t(dmu_object_type_t bonustype,
-    void *bonus, uint64_t *userp, uint64_t *groupp, uint64_t *projectp);
+typedef struct zfs_file_info {
+	uint64_t zfi_user;
+	uint64_t zfi_group;
+	uint64_t zfi_project;
+	uint64_t zfi_generation;
+} zfs_file_info_t;
+
+typedef int file_info_cb_t(dmu_object_type_t bonustype, const void *data,
+    struct zfs_file_info *zoi);
 extern void dmu_objset_register_type(dmu_objset_type_t ost,
-    objset_used_cb_t *cb);
+    file_info_cb_t *cb);
 extern void dmu_objset_set_user(objset_t *os, void *user_ptr);
 extern void *dmu_objset_get_user(objset_t *os);
 

include/sys/dmu_objset.h

@@ -254,6 +254,8 @@ boolean_t dmu_objset_projectquota_enabled(objset_t *os);
 boolean_t dmu_objset_projectquota_present(objset_t *os);
 boolean_t dmu_objset_projectquota_upgradable(objset_t *os);
 void dmu_objset_id_quota_upgrade(objset_t *os);
+int dmu_get_file_info(objset_t *os, dmu_object_type_t bonustype,
+    const void *data, zfs_file_info_t *zfi);
 
 int dmu_fsname(const char *snapname, char *buf);
 

include/sys/fs/zfs.h

@@ -1336,6 +1336,7 @@ typedef enum {
 	ZFS_ERR_EXPORT_IN_PROGRESS,
 	ZFS_ERR_BOOKMARK_SOURCE_NOT_ANCESTOR,
 	ZFS_ERR_STREAM_TRUNCATED,
+	ZFS_ERR_STREAM_LARGE_BLOCK_MISMATCH,
 } zfs_errno_t;
 
 /*

include/sys/zfs_ioctl.h

@@ -107,6 +107,22 @@ typedef enum drr_headertype {
 #define	DMU_BACKUP_FEATURE_RAW			(1 << 24)
 /* flag #25 is reserved for the ZSTD compression feature */
 #define	DMU_BACKUP_FEATURE_HOLDS		(1 << 26)
+/*
+ * The SWITCH_TO_LARGE_BLOCKS feature indicates that we can receive
+ * incremental LARGE_BLOCKS streams (those with WRITE records of >128KB) even
+ * if the previous send did not use LARGE_BLOCKS, and thus its large blocks
+ * were split into multiple 128KB WRITE records.  (See
+ * flush_write_batch_impl() and receive_object()).  Older software that does
+ * not support this flag may encounter a bug when switching to large blocks,
+ * which causes files to incorrectly be zeroed.
+ *
+ * This flag is currently not set on any send streams.  In the future, we
+ * intend for incremental send streams of snapshots that have large blocks to
+ * use LARGE_BLOCKS by default, and these streams will also have the
+ * SWITCH_TO_LARGE_BLOCKS feature set. This ensures that streams from the
+ * default use of "zfs send" won't encounter the bug mentioned above.
+ */
+#define	DMU_BACKUP_FEATURE_SWITCH_TO_LARGE_BLOCKS (1 << 27)
 
 /*
  * Mask of all supported backup features
@@ -116,7 +132,7 @@ typedef enum drr_headertype {
     DMU_BACKUP_FEATURE_RESUMING | DMU_BACKUP_FEATURE_LARGE_BLOCKS | \
     DMU_BACKUP_FEATURE_COMPRESSED | DMU_BACKUP_FEATURE_LARGE_DNODE | \
     DMU_BACKUP_FEATURE_RAW | DMU_BACKUP_FEATURE_HOLDS | \
-	DMU_BACKUP_FEATURE_REDACTED)
+    DMU_BACKUP_FEATURE_REDACTED | DMU_BACKUP_FEATURE_SWITCH_TO_LARGE_BLOCKS)
 
 /* Are all features in the given flag word currently supported? */
 #define	DMU_STREAM_SUPPORTED(x)	(!((x) & ~DMU_BACKUP_FEATURE_MASK))

include/sys/zfs_quota.h

@@ -24,23 +24,22 @@
 
 #include <sys/dmu.h>
 #include <sys/fs/zfs.h>
-#include <sys/zfs_vfsops.h>
 
-extern int zfs_space_delta_cb(dmu_object_type_t bonustype, void *data,
-    uint64_t *userp, uint64_t *groupp, uint64_t *projectp);
+struct zfsvfs;
+struct zfs_file_info_t;
 
-extern int zfs_userspace_one(zfsvfs_t *zfsvfs, zfs_userquota_prop_t type,
-    const char *domain, uint64_t rid, uint64_t *valuep);
-extern int zfs_userspace_many(zfsvfs_t *zfsvfs, zfs_userquota_prop_t type,
-    uint64_t *cookiep, void *vbuf, uint64_t *bufsizep);
-extern int zfs_set_userquota(zfsvfs_t *zfsvfs, zfs_userquota_prop_t type,
-    const char *domain, uint64_t rid, uint64_t quota);
+extern int zpl_get_file_info(dmu_object_type_t,
+    const void *, struct zfs_file_info *);
 
-extern boolean_t zfs_id_overobjquota(zfsvfs_t *zfsvfs, uint64_t usedobj,
-    uint64_t id);
-extern boolean_t zfs_id_overblockquota(zfsvfs_t *zfsvfs, uint64_t usedobj,
-    uint64_t id);
-extern boolean_t zfs_id_overquota(zfsvfs_t *zfsvfs, uint64_t usedobj,
-    uint64_t id);
+extern int zfs_userspace_one(struct zfsvfs *, zfs_userquota_prop_t,
+    const char *, uint64_t, uint64_t *);
+extern int zfs_userspace_many(struct zfsvfs *, zfs_userquota_prop_t,
+    uint64_t *, void *, uint64_t *);
+extern int zfs_set_userquota(struct zfsvfs *, zfs_userquota_prop_t,
+    const char *, uint64_t, uint64_t);
+
+extern boolean_t zfs_id_overobjquota(struct zfsvfs *, uint64_t, uint64_t);
+extern boolean_t zfs_id_overblockquota(struct zfsvfs *, uint64_t, uint64_t);
+extern boolean_t zfs_id_overquota(struct zfsvfs *, uint64_t, uint64_t);
 
 #endif

lib/libzfs/libzfs_sendrecv.c

@@ -4802,6 +4802,12 @@ zfs_receive_one(libzfs_handle_t *hdl, int infd, const char *tosnap,
 			    ioctl_err == ECKSUM);
 			(void) zfs_error(hdl, EZFS_BADSTREAM, errbuf);
 			break;
+		case ZFS_ERR_STREAM_LARGE_BLOCK_MISMATCH:
+			zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
+			    "incremental send stream requires -L "
+			    "(--large-block), to match previous receive."));
+			(void) zfs_error(hdl, EZFS_BADSTREAM, errbuf);
+			break;
 		case ENOTSUP:
 			zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
 			    "pool must be upgraded to receive this stream."));

module/os/freebsd/zfs/zfs_vfsops.c

@@ -2202,7 +2202,7 @@ zfs_init(void)
 	 */
 	zfs_vnodes_adjust();
 
-	dmu_objset_register_type(DMU_OST_ZFS, zfs_space_delta_cb);
+	dmu_objset_register_type(DMU_OST_ZFS, zpl_get_file_info);
 
 	zfsvfs_taskq = taskq_create("zfsvfs", 1, minclsyspri, 0, 0, 0);
 }

module/os/linux/zfs/zfs_vfsops.c

@@ -2131,7 +2131,7 @@ zfs_init(void)
 {
 	zfsctl_init();
 	zfs_znode_init();
-	dmu_objset_register_type(DMU_OST_ZFS, zfs_space_delta_cb);
+	dmu_objset_register_type(DMU_OST_ZFS, zpl_get_file_info);
 	register_filesystem(&zpl_fs_type);
 }
 

module/zfs/dmu_objset.c

@@ -1728,19 +1728,29 @@ dmu_objset_is_dirty(objset_t *os, uint64_t txg)
 	return (!multilist_is_empty(os->os_dirty_dnodes[txg & TXG_MASK]));
 }
 
-static objset_used_cb_t *used_cbs[DMU_OST_NUMTYPES];
+static file_info_cb_t *file_cbs[DMU_OST_NUMTYPES];
 
 void
-dmu_objset_register_type(dmu_objset_type_t ost, objset_used_cb_t *cb)
+dmu_objset_register_type(dmu_objset_type_t ost, file_info_cb_t *cb)
 {
-	used_cbs[ost] = cb;
+	file_cbs[ost] = cb;
+}
+
+int
+dmu_get_file_info(objset_t *os, dmu_object_type_t bonustype, const void *data,
+    zfs_file_info_t *zfi)
+{
+	file_info_cb_t *cb = file_cbs[os->os_phys->os_type];
+	if (cb == NULL)
+		return (EINVAL);
+	return (cb(bonustype, data, zfi));
 }
 
 boolean_t
 dmu_objset_userused_enabled(objset_t *os)
 {
 	return (spa_version(os->os_spa) >= SPA_VERSION_USERSPACE &&
-	    used_cbs[os->os_phys->os_type] != NULL &&
+	    file_cbs[os->os_phys->os_type] != NULL &&
 	    DMU_USERUSED_DNODE(os) != NULL);
 }
 
@@ -1754,7 +1764,7 @@ dmu_objset_userobjused_enabled(objset_t *os)
 boolean_t
 dmu_objset_projectquota_enabled(objset_t *os)
 {
-	return (used_cbs[os->os_phys->os_type] != NULL &&
+	return (file_cbs[os->os_phys->os_type] != NULL &&
 	    DMU_PROJECTUSED_DNODE(os) != NULL &&
 	    spa_feature_is_enabled(os->os_spa, SPA_FEATURE_PROJECT_QUOTA));
 }
@@ -2089,9 +2099,6 @@ dmu_objset_userquota_get_ids(dnode_t *dn, boolean_t before, dmu_tx_t *tx)
 	objset_t *os = dn->dn_objset;
 	void *data = NULL;
 	dmu_buf_impl_t *db = NULL;
-	uint64_t *user = NULL;
-	uint64_t *group = NULL;
-	uint64_t *project = NULL;
 	int flags = dn->dn_id_flags;
 	int error;
 	boolean_t have_spill = B_FALSE;
@@ -2145,23 +2152,23 @@ dmu_objset_userquota_get_ids(dnode_t *dn, boolean_t before, dmu_tx_t *tx)
 		return;
 	}
 
-	if (before) {
-		ASSERT(data);
-		user = &dn->dn_olduid;
-		group = &dn->dn_oldgid;
-		project = &dn->dn_oldprojid;
-	} else if (data) {
-		user = &dn->dn_newuid;
-		group = &dn->dn_newgid;
-		project = &dn->dn_newprojid;
-	}
-
 	/*
 	 * Must always call the callback in case the object
 	 * type has changed and that type isn't an object type to track
 	 */
-	error = used_cbs[os->os_phys->os_type](dn->dn_bonustype, data,
-	    user, group, project);
+	zfs_file_info_t zfi;
+	error = file_cbs[os->os_phys->os_type](dn->dn_bonustype, data, &zfi);
+
+	if (before) {
+		ASSERT(data);
+		dn->dn_olduid = zfi.zfi_user;
+		dn->dn_oldgid = zfi.zfi_group;
+		dn->dn_oldprojid = zfi.zfi_project;
+	} else if (data) {
+		dn->dn_newuid = zfi.zfi_user;
+		dn->dn_newgid = zfi.zfi_group;
+		dn->dn_newprojid = zfi.zfi_project;
+	}
 
 	/*
 	 * Preserve existing uid/gid when the callback can't determine