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From: Coly Li <colyli@suse.de>
To: linux-bcache@vger.kernel.org
Cc: linux-block@vger.kernel.org, Coly Li <colyli@suse.de>
Subject: [RFC PATCH 01/16] bcache: add comments to mark member offset of struct cache_sb_disk
Date: Sun,  5 Jul 2020 23:55:46 +0800	[thread overview]
Message-ID: <20200705155601.5404-2-colyli@suse.de> (raw)
In-Reply-To: <20200705155601.5404-1-colyli@suse.de>

This patch adds comments to mark each member of struct cache_sb_disk,
it is helpful to understand the bcache superblock on-disk layout.

Signed-off-by: Coly Li <colyli@suse.de>
---
 include/uapi/linux/bcache.h | 39 +++++++++++++++++++------------------
 1 file changed, 20 insertions(+), 19 deletions(-)

diff --git a/include/uapi/linux/bcache.h b/include/uapi/linux/bcache.h
index 9a1965c6c3d0..afbd1b56a661 100644
--- a/include/uapi/linux/bcache.h
+++ b/include/uapi/linux/bcache.h
@@ -158,33 +158,33 @@ static inline struct bkey *bkey_idx(const struct bkey *k, unsigned int nr_keys)
 #define BDEV_DATA_START_DEFAULT		16	/* sectors */
 
 struct cache_sb_disk {
-	__le64			csum;
-	__le64			offset;	/* sector where this sb was written */
-	__le64			version;
+/*000*/	__le64			csum;
+/*008*/	__le64			offset;	/* sector where this sb was written */
+/*010*/	__le64			version;
 
-	__u8			magic[16];
+/*018*/	__u8			magic[16];
 
-	__u8			uuid[16];
+/*028*/	__u8			uuid[16];
 	union {
-		__u8		set_uuid[16];
+/*038*/		__u8		set_uuid[16];
 		__le64		set_magic;
 	};
-	__u8			label[SB_LABEL_SIZE];
+/*048*/	__u8			label[SB_LABEL_SIZE];
 
-	__le64			flags;
-	__le64			seq;
-	__le64			pad[8];
+/*068*/	__le64			flags;
+/*070*/	__le64			seq;
+/*078*/	__le64			pad[8];
 
 	union {
 	struct {
 		/* Cache devices */
-		__le64		nbuckets;	/* device size */
+/*0b8*/		__le64		nbuckets;	/* device size */
 
-		__le16		block_size;	/* sectors */
-		__le16		bucket_size;	/* sectors */
+/*0c0*/		__le16		block_size;	/* sectors */
+/*0c2*/		__le16		bucket_size;	/* sectors */
 
-		__le16		nr_in_set;
-		__le16		nr_this_dev;
+/*0c4*/		__le16		nr_in_set;
+/*0c6*/		__le16		nr_this_dev;
 	};
 	struct {
 		/* Backing devices */
@@ -198,14 +198,15 @@ struct cache_sb_disk {
 	};
 	};
 
-	__le32			last_mount;	/* time overflow in y2106 */
+/*0c8*/	__le32			last_mount;	/* time overflow in y2106 */
 
-	__le16			first_bucket;
+/*0cc*/	__le16			first_bucket;
 	union {
-		__le16		njournal_buckets;
+/*0ce*/		__le16		njournal_buckets;
 		__le16		keys;
 	};
-	__le64			d[SB_JOURNAL_BUCKETS];	/* journal buckets */
+/*0d0*/	__le64			d[SB_JOURNAL_BUCKETS];	/* journal buckets */
+/*8d0*/
 };
 
 struct cache_sb {
-- 
2.26.2

  reply	other threads:[~2020-07-05 15:56 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-05 15:55 [RFC PATCH 00/16] bcache: extend bucket size to 32bit width Coly Li
2020-07-05 15:55 ` Coly Li [this message]
2020-07-05 15:55 ` [RFC PATCH 02/16] bcache: add read_super_basic() to read major part of super block Coly Li
2020-07-05 15:55   ` Coly Li
2020-07-05 15:55 ` [RFC PATCH 03/16] bcache: add more accurate error information in read_super_basic() Coly Li
2020-07-05 15:55   ` Coly Li
2020-07-05 15:55 ` [RFC PATCH 04/16] bcache: disassemble the big if() checks in bch_cache_set_alloc() Coly Li
2020-07-05 15:55   ` Coly Li
2020-07-05 15:55 ` [RFC PATCH 05/16] bcache: fix super block seq numbers comparision in register_cache_set() Coly Li
2020-07-05 15:55 ` [RFC PATCH 06/16] bcache: increase super block version for cache device and backing device Coly Li
2020-07-05 15:55 ` [RFC PATCH 07/16] bcache: move bucket related code into read_super_basic() Coly Li
2020-07-05 15:55 ` [RFC PATCH 08/16] bcache: struct cache_sb is only for in-memory super block now Coly Li
2020-07-05 15:55 ` [RFC PATCH 09/16] bcache: introduce meta_bucket_pages() related helper routines Coly Li
2020-07-05 15:55   ` Coly Li
2020-07-05 15:55 ` [RFC PATCH 10/16] bcache: handle c->uuids properly for bucket size > 8MB Coly Li
2020-07-05 15:55 ` [RFC PATCH 11/16] bcache: handle cache prio_buckets and disk_buckets " Coly Li
2020-07-05 15:55 ` [RFC PATCH 12/16] bcache: handle cache set verify_ondisk " Coly Li
2020-07-05 15:55   ` Coly Li
2020-07-05 15:55 ` [RFC PATCH 13/16] bcache: handle btree node memory allocation " Coly Li
2020-07-05 15:55   ` Coly Li
2020-07-05 15:55 ` [RFC PATCH 14/16] bcache: add bucket_size_hi into struct cache_sb_disk for large bucket Coly Li
2020-07-05 15:56 ` [RFC PATCH 15/16] bcache: avoid extra memory allocation from mempool c->fill_iter Coly Li
2020-07-05 15:56 ` [RFC PATCH 16/16] bcache: avoid extra memory consumption in struct bbio for large bucket size Coly Li

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