From: Karel Zak <kzak@redhat.com>
Date: Tue, 15 Jul 2014 10:28:16 +0000 (+0200)
Subject: libfdisk: make disk sync() optional
X-Git-Tag: v2.25~68
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=bc787727d4a114d5f8926fb9c22fb11c40d1d8c0;p=thirdparty%2Futil-linux.git

libfdisk: make disk sync() optional

 ... this allows to avoid unnecessary sync() from cfdisk.

Reported-by: Benno Schulenberg <bensberg@justemail.net>
Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/disk-utils/cfdisk.c b/disk-utils/cfdisk.c
index fb089f580b..8a627e52e4 100644
--- a/disk-utils/cfdisk.c
+++ b/disk-utils/cfdisk.c
@@ -148,6 +148,8 @@ struct cfdisk {
 	size_t	lines_idx;	/* current line <0..N>, exclude header */
 	size_t  page_sz;
 
+	unsigned int nwrites;	/* fdisk_write_disklabel() counter */
+
 	unsigned int	wrong_order :1,		/* PT not in right order */
 			zero_start :1;		/* ignore existing partition table */
 };
@@ -1805,6 +1807,7 @@ static int main_menu_action(struct cfdisk *cf, int key)
 			fdisk_reread_partition_table(cf->cxt);
 			info = _("The partition table has been altered.");
 		}
+		cf->nwrites++;
 		break;
 	}
 	default:
@@ -2019,7 +2022,7 @@ int main(int argc, char *argv[])
 	free(cf->linesbuf);
 	fdisk_unref_table(cf->table);
 
-	rc = fdisk_context_deassign_device(cf->cxt);
+	rc = fdisk_context_deassign_device(cf->cxt, cf->nwrites == 0);
 	fdisk_free_context(cf->cxt);
 	DBG(FRONTEND, ul_debug("bye! [rc=%d]", rc));
 	return rc == 0 ? EXIT_SUCCESS : EXIT_FAILURE;
diff --git a/disk-utils/fdisk-menu.c b/disk-utils/fdisk-menu.c
index c688fdfef6..f8ae95de24 100644
--- a/disk-utils/fdisk-menu.c
+++ b/disk-utils/fdisk-menu.c
@@ -459,7 +459,7 @@ static int generic_menu_cb(struct fdisk_context **cxt0,
 		fdisk_info(cxt, _("The partition table has been altered."));
 		rc = fdisk_reread_partition_table(cxt);
 		if (!rc)
-			rc = fdisk_context_deassign_device(cxt);
+			rc = fdisk_context_deassign_device(cxt, 0);
 		/* fallthrough */
 	case 'q':
 		fdisk_free_context(cxt);
diff --git a/libfdisk/src/context.c b/libfdisk/src/context.c
index 2e224b363e..61a6ce30a9 100644
--- a/libfdisk/src/context.c
+++ b/libfdisk/src/context.c
@@ -294,19 +294,24 @@ fail:
 	return -errno;
 }
 
-int fdisk_context_deassign_device(struct fdisk_context *cxt)
+int fdisk_context_deassign_device(struct fdisk_context *cxt, int nosync)
 {
 	assert(cxt);
 	assert(cxt->dev_fd >= 0);
 
-	if (fsync(cxt->dev_fd) || close(cxt->dev_fd)) {
-		fdisk_warn(cxt, _("%s: close device failed"), cxt->dev_path);
-		return -errno;
-	}
+	if (cxt->readonly || nosync)
+		close(cxt->dev_fd);
 
-	fdisk_info(cxt, _("Syncing disks."));
-	sync();
+	else {
+		if (fsync(cxt->dev_fd) || close(cxt->dev_fd)) {
+			fdisk_warn(cxt, _("%s: close device failed"),
+					cxt->dev_path);
+			return -errno;
+		}
 
+		fdisk_info(cxt, _("Syncing disks."));
+		sync();
+	}
 	cxt->dev_fd = -1;
 	return 0;
 }
diff --git a/libfdisk/src/libfdisk.h b/libfdisk/src/libfdisk.h
index 4143d9bc34..a717f4ea3e 100644
--- a/libfdisk/src/libfdisk.h
+++ b/libfdisk/src/libfdisk.h
@@ -80,7 +80,7 @@ extern int fdisk_context_set_ask(struct fdisk_context *cxt,
 extern int fdisk_context_is_readonly(struct fdisk_context *cxt);
 extern int fdisk_context_assign_device(struct fdisk_context *cxt,
 				const char *fname, int readonly);
-extern int fdisk_context_deassign_device(struct fdisk_context *cxt);
+extern int fdisk_context_deassign_device(struct fdisk_context *cxt, int nosync);
 
 extern struct fdisk_label *fdisk_context_get_label(struct fdisk_context *cxt,
 				const char *name);