From: Toomas Soome <tsoome@me.com>
Date: Thu, 16 Apr 2015 05:22:08 +0000 (+0300)
Subject: zfs: com.delphix:hole_birth feature support
X-Git-Tag: 2.02-beta3~332
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a1007c6af296172c788f3346ff3ad30b9020f723;p=thirdparty%2Fgrub.git

zfs: com.delphix:hole_birth feature support

In the past birth was always zero for holes. This feature started
to make use of birth for holes as well, so change code to test for
valid DVA address instead.
---

diff --git a/grub-core/fs/zfs/zfs.c b/grub-core/fs/zfs/zfs.c
index 0cbb84bb3..71c155df2 100644
--- a/grub-core/fs/zfs/zfs.c
+++ b/grub-core/fs/zfs/zfs.c
@@ -280,7 +280,9 @@ grub_crypto_cipher_handle_t (*grub_zfs_load_key) (const struct grub_zfs_key *key
  */
 #define MAX_SUPPORTED_FEATURE_STRLEN 50
 static const char *spa_feature_names[] = {
-  "org.illumos:lz4_compress",NULL
+  "org.illumos:lz4_compress",
+  "com.delphix:hole_birth",
+  NULL
 };
 
 static int
@@ -1751,7 +1753,7 @@ zio_read_gang (blkptr_t * bp, grub_zfs_endian_t endian, dva_t * dva, void *buf,
 
   for (i = 0; i < SPA_GBH_NBLKPTRS; i++)
     {
-      if (zio_gb->zg_blkptr[i].blk_birth == 0)
+      if (BP_IS_HOLE(&zio_gb->zg_blkptr[i]))
 	continue;
 
       err = zio_read_data (&zio_gb->zg_blkptr[i], endian, buf, data);
diff --git a/include/grub/zfs/spa.h b/include/grub/zfs/spa.h
index 7edb8ab7d..df43b6b32 100644
--- a/include/grub/zfs/spa.h
+++ b/include/grub/zfs/spa.h
@@ -279,7 +279,9 @@ typedef struct blkptr {
 
 #define	BP_IDENTITY(bp)		(&(bp)->blk_dva[0])
 #define	BP_IS_GANG(bp)		DVA_GET_GANG(BP_IDENTITY(bp))
-#define	BP_IS_HOLE(bp)		((bp)->blk_birth == 0)
+#define	DVA_IS_EMPTY(dva)	((dva)->dva_word[0] == 0ULL && \
+				(dva)->dva_word[1] == 0ULL)
+#define	BP_IS_HOLE(bp)		DVA_IS_EMPTY(BP_IDENTITY(bp))
 
 /* BP_IS_RAIDZ(bp) assumes no block compression */
 #define	BP_IS_RAIDZ(bp)		(DVA_GET_ASIZE(&(bp)->blk_dva[0]) > \