4 files changed, 22 insertions, 3 deletions

diff --git a/module/zfs/zfs_log.c b/module/zfs/zfs_log.c
index 4bb529f78..30d5c4821 100644
--- a/module/zfs/zfs_log.c
+++ b/module/zfs/zfs_log.c
@@ -540,6 +540,7 @@ zfs_log_write(zilog_t *zilog, dmu_tx_t *tx, int txtype,
 	uint32_t blocksize = zp->z_blksz;
 	itx_wr_state_t write_state;
 	uintptr_t fsync_cnt;
+	uint64_t gen = 0;
 
 	if (zil_replaying(zilog, tx) || zp->z_unlinked ||
 	    zfs_xattr_owner_unlinked(zp)) {
@@ -562,6 +563,9 @@ zfs_log_write(zilog_t *zilog, dmu_tx_t *tx, int txtype,
 		(void) tsd_set(zfs_fsyncer_key, (void *)(fsync_cnt - 1));
 	}
 
+	(void) sa_lookup(zp->z_sa_hdl, SA_ZPL_GEN(ZTOZSB(zp)), &gen,
+	    sizeof (gen));
+
 	while (resid) {
 		itx_t *itx;
 		lr_write_t *lr;
@@ -609,6 +613,7 @@ zfs_log_write(zilog_t *zilog, dmu_tx_t *tx, int txtype,
 		BP_ZERO(&lr->lr_blkptr);
 
 		itx->itx_private = ZTOZSB(zp);
+		itx->itx_gen = gen;
 
 		if (!(ioflag & (O_SYNC | O_DSYNC)) && (zp->z_sync_cnt == 0) &&
 		    (fsync_cnt == 0))
diff --git a/module/zfs/zfs_vnops.c b/module/zfs/zfs_vnops.c
index 0af03e923..8229bc9a9 100644
--- a/module/zfs/zfs_vnops.c
+++ b/module/zfs/zfs_vnops.c
@@ -740,7 +740,8 @@ static void zfs_get_done(zgd_t *zgd, int error);
  * Get data to generate a TX_WRITE intent log record.
  */
 int
-zfs_get_data(void *arg, lr_write_t *lr, char *buf, struct lwb *lwb, zio_t *zio)
+zfs_get_data(void *arg, uint64_t gen, lr_write_t *lr, char *buf,
+    struct lwb *lwb, zio_t *zio)
 {
 	zfsvfs_t *zfsvfs = arg;
 	objset_t *os = zfsvfs->z_os;
@@ -751,6 +752,7 @@ zfs_get_data(void *arg, lr_write_t *lr, char *buf, struct lwb *lwb, zio_t *zio)
 	dmu_buf_t *db;
 	zgd_t *zgd;
 	int error = 0;
+	uint64_t zp_gen;
 
 	ASSERT3P(lwb, !=, NULL);
 	ASSERT3P(zio, !=, NULL);
@@ -769,6 +771,16 @@ zfs_get_data(void *arg, lr_write_t *lr, char *buf, struct lwb *lwb, zio_t *zio)
 		zfs_zrele_async(zp);
 		return (SET_ERROR(ENOENT));
 	}
+	/* check if generation number matches */
+	if (sa_lookup(zp->z_sa_hdl, SA_ZPL_GEN(zfsvfs), &zp_gen,
+	    sizeof (zp_gen)) != 0) {
+		zfs_zrele_async(zp);
+		return (SET_ERROR(EIO));
+	}
+	if (zp_gen != gen) {
+		zfs_zrele_async(zp);
+		return (SET_ERROR(ENOENT));
+	}
 
 	zgd = (zgd_t *)kmem_zalloc(sizeof (zgd_t), KM_SLEEP);
 	zgd->zgd_lwb = lwb;
diff --git a/module/zfs/zil.c b/module/zfs/zil.c
index 7b52f9249..d9c304208 100644
--- a/module/zfs/zil.c
+++ b/module/zfs/zil.c
@@ -1744,7 +1744,8 @@ cont:
 			 * completed after "lwb_write_zio" completed.
 			 */
 			error = zilog->zl_get_data(itx->itx_private,
-			    lrwb, dbuf, lwb, lwb->lwb_write_zio);
+			    itx->itx_gen, lrwb, dbuf, lwb,
+			    lwb->lwb_write_zio);
 
 			if (error == EIO) {
 				txg_wait_synced(zilog->zl_dmu_pool, txg);
diff --git a/module/zfs/zvol.c b/module/zfs/zvol.c
index 44f9832ce..b6609363f 100644
--- a/module/zfs/zvol.c
+++ b/module/zfs/zvol.c
@@ -673,7 +673,8 @@ zvol_get_done(zgd_t *zgd, int error)
  * Get data to generate a TX_WRITE intent log record.
  */
 int
-zvol_get_data(void *arg, lr_write_t *lr, char *buf, struct lwb *lwb, zio_t *zio)
+zvol_get_data(void *arg, uint64_t arg2, lr_write_t *lr, char *buf,
+    struct lwb *lwb, zio_t *zio)
 {
 	zvol_state_t *zv = arg;
 	uint64_t offset = lr->lr_offset;